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2004-07-22 Joint WorkshopCITY OF OKEECHOBEE-mBOARD OF COUNTY COMMISSIONERS ow OKEECHOBEE UTILITY AUTHORITY W� AGEN 1. CALL TO ORDER: il. BOARD AND STAFF ATTENDANCE: Mayor James E. Kirk Council Member Noel A. Chandler Council Member Lowry Markham Council Member Dowling R. Watford, Jr. Council Member D. Clayton Williams, Jr. City Attorney John R. Cook City Administrator Bill L. Veach City Clerk Lane Gamiotea Board of County Commissions Chair Cliff Betts County Commissioner John Abney County Commissioner Clois Harvey County Commissioner David Hazellief County Commissioner Gene Woods County Attorney John Cassels County Administrator George Long County Deputy Clerk Debra Lewis OUA Board Chairperson Carl Leonard OUA Board Member Melanie Anderson OUA Board Member George Long OUA Board Member Steve Nelson OUA Board Member Elder Sumner OUA Alternate Board Member Eddie Trent OUA Alternate Board Member Harry Moldenhauer OUA Alternate Board Member Bob Oliver Executive Director L.C. Fortner OUA Attorney Tom Conely .DULY 22, 2004 JOINT WORKSHOP SUMMARY OF WORKSHOP DISCUSSION tt PAGE 1 OF 3 SCU8310N Board of County Commissioners Chairperson Betts called the July 22, 2004 joint workshop to order at 6:06*p.m. The workshop was held at the Okeechobee County Health Department Annex Building located on Northwest 9`h Avenue. Present Present Present Present Present Absent Present Present Present Present Absent Present Present Absent Absent (also sits as City appointed member to the OUA Board of Directors) Present Present Absent Absent Absent Absent Present Present Absent Present Absent 1 AGENDA III. DISCUSSION. JULy 22, 2004 - CITY/COUNTY/OUA JOINT WORKSHOP - PAGE 2 OF 3 49 - 'DISCUSSION A. Presentation from OUA Engineering Firm Metzger and Willard Mr. Dan Willard and Mrs. Susan (Groover) Martelli of Metzger and Willard addressed the boards by a presentation of regarding the Wastewater Treatment Plant Expansions. the Wastewater Treatment Plant Expansion Report. The report indicated by aerial pictures the site of the existing one million gallon per day (1 MGD) treatment plant. A projection of flows from 2003 to 2016. Based on the projected flows, the time line presented indicates that the plant will be at permitted capacity in 2005, and would be at two million gallons per day (2MGD) capacity by 2008. The expansion option schedule is, for a 2 MGD to begin now with planning and preliminary design. Begin design, plans and specification by 2005, obtain the permit and begin construction by 2006 and place the facility into operation by 2008. However, the report also gave the board options to go ahead and move forward with a 3 MGD plant and a 4 MGD plant. The cost summary is as follows: 2.0 MGD Plant Expansion $5,748,000.00 Residuals Management Class B $1,741,000.00 Effluent Disposal $1,094,000.00 TOTAL $8,583,000.00 3.0 MGD Plant Expansion $9,564,000.00 Residuals Management Class B $1,741,000.00 Effluent Disposal $1,615,000.00 TOTAL $12,920,000.00 3.0 MGD Plant Expansion $9,564,000.00 Residuals Management Class B $1,741,000.00 Effluent Disposal $1,615,000.00 TOTAL $12,920,000.00 4.0 MGD Plant Expansion $2,572,000.00 (add these figures with 3.0 MGD figures) Residuals Management Class B $16,000.00 Effluent Disposal $611,000.00 TOTAL $3,199,000.00 50 JULy 22, 2004 - Ctry/COuNTY/OUA JOINT WORKSHOP - PAGE 3 OF 3 �`�AGENDA III. DISCUSSION CONTINUED. A. Presentation from OUA Engineering Firm Metzger and Willard regarding the Wastewater Treatment Plant Expansions continued. IV. ADJOURN WORKSHOP. Please take notice and be advised that if a person decides to appeal any decision made by the City Council with respect to any matter considered at this meeting, he/she may need to insure that a verbatim record of the proceeding is made, which record includes the testimony and evidence upon which the appeal is to be based. City Clerk tapes are for the sole purpose of backup for official records of the Clerk. ATTEST: �l James E�Kirk, Mayor14 'All s A \ Lane 6amiotea, Cit Clerk r DISCUSSION The major components for a plant expansion are the Headworks; Master Pump Station; Aeration; Clarification; Filtration; Chlorine Contact and Effluent Pumping; Administration/Laboratory Building. There were diagrams presented on how the site would be laid out with all the options. Then a breakdown of the expansion costs for each of the options. Mrs. Martelli went on to explain the residuals management. The effluent disposal and reuse portion of the expansion and the cost breakdown for each of these phases in the project. The board members then discussed what would be the best method to move forward with the expansion. The OUA Board will meet in regular session on August 10, 2004 at 8:30 a.m. to decide which expansion amount to proceed with, 2.0 MGD, 3.0 MGD or 4.0 MGD. Once this determination has been made, all the boards will know how much money will be required to expand the plant. Mr. Dale Milita was also present and he is to begin working on finding various funding resources. Once again, all members of each of the boards agreed this is a community problem and the three entities need to continue to work together to solve this problem as efficiently, timely and cost effective as possible. There being no further discussion, County Chairperson Betts adjourned the workshop at 7:05 p.m. i Ll The Okeechobee News P.O. Box 639, Okeechobee, Florida 34973 (863) 763-3134 Published Daily STATE OF FLORIDA COUNTY OF OKEECHOBEE Before the undersigned authority personally appeared Judy Kasten, who on oath says she is Publisher of the Okeechobee News, a DAILY Newspaper published at Okeechobee, in Okeechobee County, Florida, that the attached copy of advertise- ment, being a Q_ in the matter of Cjo c-:!,c� I in the 19th Judicial District of the Circuit Court of Okeechobee County, Florida, was published in said newspaper in the issues of --�1\�_,\Ca Affoant further says that the said Okeechobee News is a newspaper published at Okeechobee, in said Okeechobee County, Florida, and that said newspaper has heretofore been published continuously in said Okeechobee County, Florida each week and has been entered as second class mail matter at the post office in Okeechobee, in said Okeechobee County, Florida, for a period of one year next preceding the first publication of the attached copy of advertisement-, and affiant further says that she has neither paid nor promised any person, firm or corporation any discount, rebate, commission or refund for the purpose of securing this advertisement for publication in the said newspaper. �(mac— qtnd subscrobefore me this 'PUBLIC NOTICE The Okeechobee County Board of County Commissioners, the City _ Council of. Okeechobee, and the Okeedhobee .11p'lily Authority will cdrw me a woogds-1a pp session, on pp�m� n 4he Oke ,2ho0beee Courtly Hsalth Deparbnent auditorium, 1798 NW Avenue, Avenue„ Oke'echo- bee, Florida io discuss compepen- shre danninu and fundkw it nec Arty person deciding to apeeal�a y d iSk) made by the BB Courtly .Commissioners with re- sped toany matter considered ai - this meetlnpp will need a,record of the proceedings, and th for such. purposes,.he or she will need to ensure that, a verbatke record of such-pproceedingps Is made, 4ddch reeord'shall.include the testlmomy and evidence -upon which the ap- peal is to ba based. Cfff Bees, Jr., Chairman Board:ef County Commissioners Sharon Robertson, Clerk 494572 ON 71i6� issionere — day of / y7� L„�\� A.D 20 q0A R. Brown Notary Public, State of Florida at Larg�� B�" - Commission #DD272118 1. .,7 Expires: Jan 17, 2008 9'Fod i`pf- Bonded Thru wl, Atlantic Bonding Co., Inc SA"* at ceo r�r�uy - �yiall "c"retP"`y Not 7caeAoalah, 4&Aose' �o ,�"t `%uy. Ciasited to ,uu r6e,� y� co�cld do. Suaa�c. "*�' "" 4&4a, Atoleidieed doedat' all et ecticen Da"`e"`.ry loose 0-14f scald 4-Oka doutq "� tla.cdd. aacton that Cestaca a.rcaccato� e�ai°`c' sot ecec o� elcat. DAP doedc allow. to $13 arr&4k lcaae tau cscade an�i decidio ' aaoccyce gai rg 3 7kat d t�Ge needed. �urd ce yset. loak �ac eueuy �aadi�Cc eve,r� "A to- daze, dil,� doa�rd kadc t decided kou.. to suer-to.�wrd lef�ed ga•`t a.,cd �6'"'rQue �uwcd,q,• � is tticce a�cix. add Dauid, co..w d�nead oat de4t, eAae cadtd MONe`y alder. farce cd issue alde., 'fit A"&e w, ea WeeA okeeckodee goEaq, u<e u.a„ct to de ale a.cd Ze r 4w ,G.ev, 4OC4 aze u<illi.cq ea gee else doll 'e cfttiuca.cce azliacit�l� "' addcdt «at a kucdeca�ece. 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"N�. �eiag is do �"e"�ct'.,,. `"g' ad�'riui°ttatio�c/laeE wouy ka, . d fuaae lad uRozk tlia�c euen e-44444W coot �cwc¢ �n e4aa 2 - 3 - 4 u�y 30� coaterge�ceay - tkat ia. ata�cdcvtd do&4i f, 5,77 1,14 - ov 3 o*e* 9.6 .rcd%%* scot add 2Mgd colo�c, a :O� 'eoidacalo cite to mead Ct -dace to eoaurtay ond�ca�ccc Wastewater Treatment Plant Expansion July 2004 1995 M k I�. 0 Existing Wastewater Treatment Plant Projected Flows for OUA WWTP (2004-2016) End of Year Max MO 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 Taylor Creek 122,500 122,500 Isles Ousley Infill 10,000 10,000 10,000 10,000 Treasure Island 112,000 223,000 50,000 SW (160 units) 30,000 10,000 SE ) unitsts) 25,000 37,500 50,000 62,500 50,000 25,000 NE (300 units) 25,000 50,000 c Misc Projects 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 Other rowt h 19,150 22,691 27,696 33,563 43,040 47,491 51,116 54,269 56,875 58,922 61,020 63.171 65,375 Total YR, GPD 141,650 200,191 234,696 279,063 178,040 144,991 126,116 104,269 81,875 83,922 86,020 88,171 90,375 Average Day, GPD 766,000 907,650 1,107,841 1,342,537 1,721,601 1,899,641 2,044,632 2,170,748 2,275,016 2,356,892 2,440,814 2,525,834 2,615,005 2.705,380 Maximum Day, GPD 1149,000 1.406,858 1,717,154 2,080,933 2,668,481 2,944,443 3,169,179 3,364,659 3,526,275 3,653,182 3,783,262 3,916,593 4,053,258 4,193,339 0 Future Expansion Schedule EXPANSION OPTION, 2004 Expansion Activities* 2 MGD 3 MGD Begin Planning & Preliminary Design Now 2013 Begin Design, Plans & Specifications 2005 2014 Obtain Permit & Begin Construction 2006 2015 Place Facility into Operation 2008 2017 * Per 62-600.405(8) FAC M In I Cost Summary 2.0 MGD 3.0 MGD Wastewater Treatment Plant 5,748,000 9,564,000 Expansion Residuals Management — 1,741,000 1,741,000 Class B Effluent Disposal 1,094,000 1,615,000 TOTAL $ 8,583,000 $ 12,920,000 Cost Summary Future 2.0 MGD 3.0 MGD 4.0 MGD (After 3.0 MGD) Wastewater Treatment Plant 5,748,000 9,564,000 2,572,000 Expansion Residuals Management — 1,741,000 1,741,000 16,000 Class B Effluent Disposal 1,094,000 1,615,000 611,000 TOTAL $ 8,583,000 $ 12,920,000 $ 3,199,000 r Wastewater Treatment Plant Expansion Major Components Headworks . Master Pump Station Aeration Clarification Filtration . Chlorine Contact and Effluent Pumping . Administration/Laboratory Building DifflIM Lon HOLOW Pw FLAN k9W Asomy AND FM T-AW EMMM CHLOW OWACT OM NOW PROPOMD MA3793 MW VATM ADRAIMM UHT I 7--M laic AIgN PKFOMD M DE DOWLMM PLW WD YASIEA lUIP ifA7101 — IE,�,WD 6M.DIENf _ �ITA('C'{•'� — Maw owwr 7/7101 OrN1�011 (� m1wo D AD� floaftY 3PUTMA Sox PiCPOlD CL17R 2A •Ai T,All LCLOID. 67UT11MG PW�DLE! TO WE DWMZH J' IRdi pow OfA1110 !D<O NOiAMO /OIO >� go tnsnra noN rarzw Aasos.r � �� OIYO[ ■ CORAL?CORAL? 10 Awl= WP-tAi f IiIOFND� �OfliMt PAfli�OCkD 1. 2. 3. 4. 5. 6. 7. 8. a 10. 11. 12. 13. 14. p Subtotal 15. TOTAL WWTP Expansion Cost Headworks Demolition CSAS WWTP Master Pump Station Flow Splitter Box Aeration Basin Phosphorus Removal Tank Clarification Filtration Chlorine Contact Chamber/Effluent Pump Station Administration/Laboratory Building Site Work, 5% Electrical, 15% Yard Piping, 15% Mobilization, 10% Contingency, 30% 2.0 MGD 708,375 100,000 475,000 501,000 600,000 180,000 110,000 220,000 144,719 455,864 524,244 401,920 4,421,122 1,326,336 5,747,458 3.0 MGD 708,375 100.000 475,000 100,000 1,653,100 600,000 450,000 360,000 150,000 220,000 240,824 758,595 872,384 668,828 7,357,105 2,207,132 9,564,237 Future 4.0 MGD (After 3.0 MGD) 80,000 550,000 500,000 165,000 64,750 203,963 234,557 179,827 1,978,096 593,429 2,571,525 Residuals Management Dewater . Hauling . Disposal Residuals Information RESIDUALS SUMMER WINTER TIPPING VOLUME, QUANTITY, TIPPING NUMBER OF VOLUME, QUANTITY, TIPPING NUMBER OF COST, TOTAL ALTERNATIVE GPD TONS/ DAY COST, $/YR TRIPS/ DAY GPD TONS/ DAY COST, $/YR TRIPS/ DAY FOR YEAR Liquid Residuals 50,000 208.5 $ 1,301,040 9 100,000 417 $ 2,602,080 17 $ 3,903.120 Cost=$0 Liquid Residuals, Thickened 12,500 52.1 $ 325,260 3 25,000 104.3 $ 650,520 5 $ 975,780 Cost= $50,000 Class A Dewatered 52 CY 9.1 $ 56,784 3 52 CY 9.1 $ 56,784 3 $ 113,568 Cost= $3,081,800 Class B Dewatered 80 CY 10.1 $ 63,024 5 80 CY 10.1 $ 63,024 5 $ 126,048 Cost= $1,740,900 21. 22. 23. 25. 26. 27. Subtotal 28. TOTAL Residuals Management Cost Residuals Management Equipment Residuals Management Building Residuals Storage Containers Site Work, 5% Electrical, 12% Yard Piping, 15% Mobilization, 10% Contingency, 30% Future 4.0 MGD 2.0 MGD 3.0 MGD (After 3.0 MGD) 793,050 793,050 - 140,000 140,000 - 10,000 10,000 11,000 47,153 113,166 141,458 94,305 1,339,131 401,739 1,740,870 47,153 113,166 141,458 94,305 1,339,131 401,739 1,740,870 1,100 12,100 3,630 15,730 y ID Effluent Disposal and Reuse Williamson Cattle Company Citrus Irrigation - Existing On -Site Spray Irrigation y Off -Site RIBS Deep Well Injection On -Site Constructed Wetlands ■, ■ i. u ■ Effluent Disposal Costs Alternative Opinion of Costs $1,620,000 and Hamrick Property — $32,400/YR to Lease or Rapid Infiltration Basins $ 2,600,000 to Purchase Underground Injection Well $ 3,000,000 $ 1,094,000 On -Site Wetlands $ 1,615,000 Capacity 440,000 gpd U/K — Anticipated over 4,000,000 gpd 2,000,000 gpd 3,000,000 gpd 0 i b* IC 1 n � Typical Underground Injection Well .4 FLOATING PLANTS INLET/OUTLET STRUCTURE EMERGENT PLANTS Y v" Typical Florida Disposal Wetland Lakeland West Palm Beach IV Map of Wastewater Wetlands in Florida (Approalm" l"alinwr ) ReviseO 4,,25 tit 1 Bayou Marcus 2 Rice Creek 3 St. John's County SR16 4 Blacks Ford 5 Hurlburt Field 6 Apalachicola 7 Boot Wettand 8 Jasper 9 Monticello 10 OCESA 11 Orlando Easterly Wetlands 12 Slue Heron 13 Yutee 14 South Central Regional 1S Yankee Lakes, Seminole 16 Hilliard 17 Waldo Wetlands 18 East Central Regional 19 Indian River 20 Leesburg 21 Wakodahatchee Wetland 24 7 �271 22 Northwood 23 Dear Park Wetlands ;'t2 28 19 24 Petro Truckstop I` 25 Spencer � 26 Pace Wetland a 27 Lakeland. Glendale 28 Ft. Meade 2g 29 Glades County 30 Port of the islands South % 21 31 Orange County Northwest ' '} 32 High Springs Commercial Park 130 4a Color Key Natural Wetlands Man-made Wetlands Combination of Natural and Man-made • Effluent Disposal Cost 2.0 MGD 3.0 MGD Future 4.0 MGD (After 3.0 MGD) 31. Earthwork 312,000 480,000 180,000 32. Influent Structures 30,000 30,000 12,000 33. Discharge Structures 30,000 30,000 12,000 34. Gravel Beds 7,500 10,000 7,500 Modifications to Perimeter Ditch 10,000 12,000 35. Discharge Structure 36. Sod 50,000 75,000 30,000 37. Emergent Plants 70,000 100,000 30,000 38. Submerged Plants 87,000 135,000 50,000 39. Floating Plants 35,000 60,000 30,000 40. Mosquitofish 2,000 3,500 2,000 41. Site Work, 5% 31,675 46,775 17,675 42. Yard Piping, 15% 99,776 147,341 55,676 43. Mobilization, 10% 76,495 112,962 42,685 Subtotal 841,446 1,242,578 469,536 44. Contingency, 30% 252,434 372,773 140,861 F ' TOTAL 1,093,880 1,615,351 610,397 .o I 0 m V Lilt Nk�lm� • • 0 OKEECHOBEE UTILITY AUTHORITY TECHNICAL MEMORANDUM NO. 1 WASTEWATER TREATMENT PLANT EXPANSION July 2004 MEUGER & WILLARD, INC. Civil • Environmental Engineers 8600 HIDDEN RIVER PARKWAY SUITE 550 TAMPA, FL 33637 913-977-6005 TECHNICAL MEMORANDUM NO. 1 WASTEWATER TREATMENT PLANT EXPANSION TABLE OF CONTENTS SECTION DESCRIPTION PAGE 1. INTRODUCTION 1-1 2. SUMMARY OF EXISTING TREATMENT 2-1 GENERAL 2-1 H EADWORKS 2-6 Screening 2-6 Grit Removal 2-6 AERATION 2-6 Orbal 2-6 CLARIFICATION 2-8 FILTRATION 2-8 CHLORINE CONTACT AND CHLORINATION 2-12 AEROBIC DIGESTERS 2-14 EFFLUENT REUSE AND DISPOSAL 2-14 3. EXISTING REGULATIONS 3-1 FEDERAL 3-1 STATE 3-2 4. CURRENT AND FUTURE FLOWS AND QUALITY 4-1 EXISTING QUANTITY 4-1 FUTURE QUANTITY 4-1 ANTICIPATED QUALITY 4-9 5. POTENTIAL TREATMENT STRATEGIES 5-1 MASTER PUMP STATION 5-1 HEADWORKS 5-3 Screening 5-6 Jones + Attwood, Inc., Lo-Flow Screening Unit 5-6 MTS Spirac CS 500 Screen 5-7 MTS Spirac ST Screen 5-8 Parkson Aquaguard 5-8 Grit Removal 5-9 Eutek Headcell 5-9 Jones + Attwood, Inc., Jeta-Grit 5-12 Smith & Loveless, Pista-Grit 5-13 Walker Process Rolling Grit 5-14 Fluidyne Hydro -Grit 5-14 Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion TOC - 1 June 2004 • • • SECTION DESCRIPTION PAGE AERATION 5-17 Two -Channel Option 5-17 Three -Channel Option 5-18 Replace Existing Aeration System 5-20 CLARIFICATION 5-22 FILTRATION 5-22 US Filter Davis/Davco TBF 5-22 Parkson Smartfilter TBF 5-22 Infilco-Degremont Automatic Backwash Filter 5-23 Sanitaire/ABJ Drum Filters 5-23 US Filter/Kruger Hydrotech Disc Filter 5-23 Parkson Dynasand Filter 5-26 Tetra Process Technologies DeepBed Filter 5-27 EFFLUENT PUMPING, CHLORINE CONTACT AND CHLORINATION 5-29 DETAILED OPINION OF COSTS 5-33 6. POTENTIAL STRATEGIES FOR THE EXISTING CONTACT STABILIZATION FACILITY 6-1 FLOW EQUALIZATION 6-2 LEACHATE TREATMENT 6-3 SEPTAGE TREATMENT 6-4 7. RECOMMENDED PROGRAM FOR WWTP EXPANSION 7-1 APPENDIX A Manufacturer's Data — AloF =N"1^DVD B Opinion of Probable Construction C osts C Design Calculations — .Jo7- Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion TOC - 2 June 2004 LIST OF FIGURES NUMBER DESCRIPTION PAGE 1-1 OUA Service Area 1-3 2-1 Plant Site 2-4 2-2 Hydraulic Profile 2-5 2-3 Existing Influent Structure 2-7 2-4 Existing Aeration Basin 2-9 2-5 Existing Clarifiers 2-10 2-6 Existing Filters 2-11 2-7 Existing Chlorine Contact C hamber 2-13 4-1 Projected Flows 4-8 5-1 Headworks and Master Pump Station Locations 5-2 5-2 Master Pump Station Details 5-4 5-3 Typical Headworks 5-5 5-4a Lo-Flow Screening Unit 5-6 5-4b Washpactor 5-7 5-5 Spirac CS 500 Screen 5-7 5-6 5-7 Spirac ST Screen Aquaguard Screening Unit 5-8 5-8 5-8 Eutek Headcell 5-10 5-9 Eutek Slurry Cup and Grit Snail 5-11 5-10 Jeta-Grit 5-12 5-11 Pista-Grit 5-13 5-12 Walker Rolling Grit Chamber 5-14 5-13a Hydro -Grit Plan 5-15 5-13b Hydro -Grit Elevation 5-16 5-14 Two -Channel Aeration Basin Modifications 5-19 5-15 Three -Channel Aeration B asin Modifications 5-21 5-16 Infilco-Degremont ABW Filter 5-24 5-17 ABJ Drum Filter 5-25 5-18 Hydrotech Disc Filter 5-26 5-19 Dynasand Filter 5-27 5-20 Tetra DeepBed Filter 5-28 5-21 Expand Existing Chlorine Contact Chamber 5-30 5-22a Cast -In -Place Chlorine Contact Chamber and Effluent Pump Station 5-31 5-22b New Chlorine Contact Chamber Details 5-32 6-1 Septage Treatment System 6-6 7-1 Proposed Site Schematic 7-2 • Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion TOC - 3 June 2004 • • • LIST OF TABLES NUMBER DESCRIPTION 1-1 Phosphorus Loads in Lake Okeechobee 2-1 Design Conditions for Units 3-1 Minimum Treatment Standards 4-1 Historical Flows at the WWTP 4-2 Projected Flows 4-3 Characteristics of Flow and Strength of Waste 5-1 Equipment Cost — P ista-Grit 5-2 Opinion of Probable Cost —Alternative 1 5-3 Opinion of Probable Cost — Alternative 2 5-4 Opinion of Probable Cost — Alternative 3 7-1 Proposed Treatment Plan Technical Memorandum No. 1 WWTP Expansion TOC - 4 PAGE 1-4 2-15 3-4 4-2 4-7 4-9 5-13 5-33 5-34 5-35 7-3 Okeechobee Utility Authority June 2004 0 SECTION 1 • INTRODUCTION In recent years, the Florida Department of Environmental Protection, the South Florida Water Management District, the US Army Corps of Engineers, the University of Florida — Institute of Food and Agricultural Studies, the Florida Department of Health and the Florida Department of Agricultural and Consumer Services have been studying Lake Okeechobee — the largest freshwater lake in Florida. The agencies have determined that phosphorus loadings within the Lake's watershed area have contributed to excessive phosphorus loadings within the Lake itself. High phosphorus levels lead to eutrophication which causes algal blooms, leading to unpleasant tastes and odors in potable water withdrawn from the Lake. The Lake is a major source of revenue to the area for commercial and sport fishing. Eutrophication reduces the ability of fish and other aquatic species and plants to grow and reproduce properly. Many efforts have been extended by all of the above agencies to reduce the phosphorus levels in the Lake to a "background" level of 40 ppb. Many projects are being designed and constructed to reduce the quantity of phosphorus to this level. The Okeechobee Utility Authority (Authority) intends to provide sewerage facilities to remove septic tanks and small package treatment facilities from the area adjacent to the Lake and within the service area of the Authority. The Authority's service area is illustrated in Figure 1-1. In December 2003, a report entitled, Okeechobee Utility Authority Wastewater Facilities Plan, was completed by Metzger & Willard, Inc., and submitted to the Florida Department of Environmental Protection and the Authority. As a part of the report, it was determined that by providing a regional sewage system for the collection, transmission, treatment and disposal to the areas adjacent to the Lake approximately 6 tons of phosphorus per year will be prevented from entering Lake Okeechobee, as shown in Table 1-1. Technical Memorandum No. 1 WWTP Expansion Okeechobee Utility Authority July 2004 r1 • • To provide adequate capacity at the Authority wastewater treatment plant, the capacity of the facility will need to be increased. Therefore, this technical memorandum addresses the needs of the expanded facility. Technical Memorandum No. 1 WWTP Expansion Okeechobee Utility Authority 1-2 July 2004 9 0 0 �chobee mocks FIGURE 1-1 OUA SERVICE AREA METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, Florida 33637 (613) 977-6005 • • TABLE 1-1. PHOSPHORUS REDUCTION TO LAKE OKEECHOBEE AS A RESULT OF PROVIDING A REGIONAL SEWERAGE SYSTEM TO AREAS ADJACENT TO THE LAKE, PHOSPHORUS REDUCTION, AREA FLOW, GPD TONS/YEAR * Taylor Creek Isles 246,900 1.54 Ousley Infill 12,400 0.08 Treasure Island 385,000 1.92 Big "O" 78,300 0.42 Buckhead Ridge 140,200 0.66 Ancient Oaks 156,040 0.73 Blue Cypress 57,800 0.27 TOTAL 1,076,640 5.62 =6 * Based upon 4.09 mg/L - Concentration reaching canals/Lake Okeechobee. Developed through literature search and sampling program in Okeechobee. (40% of value of septic tank effuent escaping into the soils.) Technical Memorandum No. 1 WWTP Expansion 1-4 Okeechobee Utility Authority June 2004 • SECTION 2 SUMMARY OF EXISTING TREATMENT General The major portion of the wastewater system acquired by the Authority in 1995 is the system formerly owned and operated by the City of Okeechobee. Since then, the Authority has been actively expanding the system beyond the former city service area to include the areas closest to Lake Okeechobee. The major treatment facility received from the City was a 0.6 MGD contact stabilization facility, sited on a 407-acre site, located north of the City along Cemetery Road, (39th Boulevard NE) and east of U.S. Highway 441. In September 1998, the Authority completed the construction of a 1.0 MGD extended aeration facility on the same site for $4.25 Million, placed it on line and removed the old 0.6 MGD plant from service for repairs. Included in this project, in addition to the wastewater treatment plant expansion, were on -site effluent disposal improvements. Subsequently, in January 2000 the Authority added additional effluent storage by constructing a 23-acre lined pond at a cost of $412,050 that more than doubled the storage capacity, and completed repairs to the older ponds. In addition to the wastewater treatment plant improvements and on site effluent system expansion, the Authority has also expanded the offsite effluent reuse system by connecting additional acreage of citrus on the Williamson Cattle Company properties. The Authority has a contract with the State of Florida Department of Juvenile Justice and receives approximately 51,000 gallons per day of wastewater from the Eckerd Youth Facility, a state run correctional facility for troubled youth, which is located adjacent to the WWTP site. Previously, the Authority operated a state owned package plant at the Youth Facility and pumped the treated wastewater for filtration and disposal at the Authority's plant. The wastewater treatment plant has been removed from service and the raw wastewater is now treated, filtered and disposed with the rest of the flow at the Authority's plant. The Authority assumed an agreement for the WWTP site, which was entered into by the City of Okeechobee and the Florida Department of Health and Rehabilitative Services on May 20, 1986 for a period of 48 years and which remains in Technical Memorandum No. 1 Okeechobee Util ity Authority WWTP Expansion 2-1 July 2004 effect beyond that period, unless one of the parties decides to terminate the agreement after providing 180 days notice. Effluent disposal is accomplished under a notably successful program, whereby water is reused as agricultural irrigation for approximately 700 acres of citrus groves on a nearby commercial citrus and cattle operation. A ten-year contract for this reuse program was executed in May 1997 and has an automatic renewal clause for successive two-year terms beyond the initial ten year period, unless terminated by either party with a minimum 360 days notice prior to the expiration of the initial term, or any successive two-year term. With 100 percent utilization, this reuse program has been demonstrated to be one of the more successful water conservation programs in the state. To the extent that the water is not required for citrus irrigation, it is used on approximately 310 acres on site for the production of hay, which is operated and ha rvested by a commercial interest. Based upon groundwater monitoring, there have been no problems associated with the reuse of the treated effluent in this program. At the time of the formation of the Authority in 1995, there were approximately 20 small ispackage wastewater treatment facilities in its service area. The Authority operates a number of these package plants and others are privately operated. As noted, the Eckerd facility has now been removed from service and two others were removed from service at the end of May 2002. Three more were removed by April 2003 upon completion of the Ousley Estates Phase I and Phase II projects. Four more have been removed from service with the recent completion of the Taylor Creek Isles Project in April 2004. Most of the package plants serve recreational and residential communities along the perimeter of Lake Okeechobee. Presently, residuals from six of the facilities are being hauled and treated at the main WWTP facility on Cemetery Road. One wastewater treatment plant, the Okee-Tantie facility, was formerly owned by Okeechobee County and serves the recreational area of the same name. The Authority is also operating this facility, through a contract with an operations company. No wastewater facilities were received from OBWA, since that agency did not provide sewer service. It is the intent that the Okeechobee Utility Authority, in cooperation with the State of Florida Department of Environmental Protection and South Florida Water Management District, and when funds are available, will continue to remove the small plants from service and connect the associated collection systems to the regional Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 2-2 July 2004 wastewater system. This will reduce the phosphorus load to the waterways and the Lake. In Fiscal Year 2005, an expansion of the wastewater treatment facility is anticipated to commence to increase the treatment capacity. This expansion will be necessary due to the growth of the customer base, from expansion of the collection system, the removal of Authority owned package wastewater treatment plants plus those expected to be acquired, and the associated connection of existing collection systems. Collection system additions recently completed with the Taylor Creek Isles project enabled the removal of four package wastewater treatment plants - Snug Harbor MHP, Four Acres MHP, Pier Two Motel, and Taylor Creek Lodge. Although the Okeechobee Utility Authority, FDEP and SFWMD have the goal of removing all package plants in the vicinity of Lake Okeechobee, it is not anticipated to eliminate any beyond those in the current program until additional funding is available for this purpose. The 1.0 MGD Okeechobee Utility Authority wastewater treatment plant was completed and placed in service in 1998. The plant was engineered and constructed so that the is capacity could be doubled to 2.0 MGD with relative ease and within normal permitting procedures. The plant site is shown in Figure 2-1. Hydraulics through the facility are shown in Figure 2-2. The plant is a 1.0 MGD extended aeration treatment facility, Orbal process, oxidation ditch facility and consists of a 165 feet by 96 feet aeration basin having two rings, to which can be added a third ring to double the capacity. Other major components include two 85-foot diameter clarifiers and two 80-foot diameter aerobic digesters, a chlorine contact basin, three multi -media traveling bridge filters, aeration equipment, pumping and piping equipment, plus all other equipment required for a modern, fully operational facility. The major water -containment structures are constructed of pre -stressed concrete. Existing reclaimed water transfer pumps were upgraded as part of the expansion. Also, as part of the expansion, additional agricultural filters were added to the -existing ones and the existing filters were provided with new filter media. All flow enters the plant through an 18-inch force main, which discharges into a screening unit, then i nto the aeration basin. Technical Memorandum No. 1 Okeechobee Util ity Authority WWTP Expansion 2-3 July 2004 • is 0 EXISTING LINED HOLDING POND ENSWO fOII. EXISTING LINED HOLDING POND S]A twW MIG tM00 PP� yyr----------------------------------------------------------------------- 1 ,PP iAW E00JA5 I I I PP I I I W N NAA i lu' SiA tSa50 L-- � CA tw' av � taG IOa00 1Y+00 1-00 1-- ASP -T w0A0 1t+00—� ivae� I5+00 Ifi+00 dJ ;N_________________am ---------------------- ��� I 4t1 _______-_____i W BOLT t WASHFA� , r n , E105wW ��-1t_____________________________� I I 1 F.F. 77.0 ].A Ilrq, aN I ;/ w / „'ENERATORJ %� I f l l I • V V I I� y II I i i-»------ �` U Iy III » .Y J-----�-- p ; Ma tta!) , I y� ,J -- ______-_r_ I NIQ I71 r 'Y. 'd 1 I . :EXIST. TREAT4ENT PSANT »r-----_--►____r ___________�_�____� IM TT _ r----------+------------- au. ; I i i��p��''<� I �O/�'•~,:„1.„7 FRt\j ___y' ' i------------- !;I,Af?i4i R I 7. Ikl ` CI -,RIFT k iF, -_ ._ _ off_ 1 I IL I �_ t.•NE_i.. x.•ul. I l � „�1 1 �4iTa -- N --------- w Ili `\ ILI u LJ: FILTERS !a Jai'' H la Y PA FIGURE 2-1 NOTE: EFFLUENT PUMP STATION, EXISTING WWTP SITE AGRICULTURAL FILTERS AND FORCE MAIN (` TO CITRUS IRRIGATION NOT SHOWN. o METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, Florida 33637 (813) 977-6005 60 58 56 E 54 L 52 Rom. E 50 V 48 A 46 T 44 42 40 0 38 N 36 obAN Ar. a 34 N 32 V 30 --T l G 28 26 0 24 AERATION BASIN I L_ S CONTACT STABUZ TION a PLANT (CUT I SEI) yNt t A— CLAMM (OUT OF SERMR) a� II l it I CONTACT WAMLIEATNIN PLANT CLAIRERS 9 Oul" u CK)FAK �,�R CONTACT CIUME CONTACT EFFLUENT B EFFLUENT FILTER$ PUMP STATION S<p� 4 WENT STATION e AfJSCU1.TURAL FILTER To ON-!1[ 090YL HY m+a qQ STpMQ FpA) 3� 60 58 56 54 E 52 L 50 E 48 V 46 A 44 T 42 40 38 0 36 N 34 32 N 30 V 28 G 26 0 24 FIGURE 2-2 EXISTING HYDRAULIC PROFILE METZGER & WILLARD, INC. Civil • Enwronmentol Engineers Tampa, Florida 33637 (613) 977-6005 More wastewater treatment operating personnel were added with the c onstruction of the 1.0 MGD W WTP. Current staff consists of a lead operator and five additional operating personnel. The Authority has an active and effective safety program at the facility. In summary, great improvements have been made in the wastewater treatment system since the Authority acquired the system. The following describes the major components of the existing treatment system. Headworks SCREENING: The existing screening system includes two Andritz static screens rated for 1.5 MGD each. The original static screens were replaced in 2003 due to corrosion problems. The new screens are manufactured of 316L Stainless Steel. The screens are shown in Figure 2-3. The screen overflow box fills and spills down an inclined stainless steel screening surface. Solids too large to fit through the openings in the screen roll down to the base of the screen to be collected. Screened water falls through the screen surface and exits the screening unit to the aeration basin. GRIT REMOVAL: The facility has no means of grit removal other than what may catch in the screening units. Aeration ORBAL: The existing aeration basi n is a two -channel Orbal P rocess, as designed by US Filter/Envirex, and constructed in 1998. The Orbal is a complete mix, looped reactor system. The unit can be easily expanded to accommodate future load conditions, either by adding on additional aerator assemblies to the existing channels, or by adding on an additional channel to the existing channels. State standards for multiplicity are met with single basin designs, since the Orbal has dual basin capability in a single basin. The Orbal is reported to have a high buffer capacity for shock loads. Influent enters the outer channel of the Orbal unit (containing approximately one-half of the volume), which is operated under an oxygen deficit to promote nitrification-denitrification. The second channel is designed for a higher oxygen rate; however, the oxygen demand in the Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 2-6 July 2004 0 0 0 STEEL OR BAR SCREEN FIBERGLASS ASSEMBLY HEIGHT AS REQUIRED TO RECEIVE MATERIAL TROUGH FROM SCREENS WITH OUT SPLASHING 18' �C6z13 EL. 49.46 STEEjGRATING r- I I I I I I � I I I DUMPSTER ' BY OWNER j 1 I I 1 I I I I I I 10" INFLUENT FLEXIBLE PIPE 12" TEE , 2'-0' 12'_ I lit FFLUEN 18' 12- {,Lr R D. rl� RESTRAINED FLANGE ADAPTER COUPUNG STAIR LANDING 7 � 12" TEE 51.83 T INV. EL SO.10 ��E] E _u-4 FLEXIBLE PIPE `Ng8z35� PIPE SUPPORT 9'-9" �!a 4 jw 2' CLR. J � lil FIGURE 2-3 i N EXISTING INFLUENT STRUCTURE METZGER & WILLARD, INC. III I I I Civil • Environmental Engineers �ulsH WADE E� Tampo, Florido 33637 (813) 977-6005 0 second channel is lower and a small amount of oxygen need s to be delivered to maintain a higher dissolved oxygen rate. T he disc aerators provide oxygenation and mixing for the system. The existing aeration basin is shown in Figure 2-4. The existing aeration system consists of four aerators in each channel. The outer channel aerators are driven by the same motors as the interior channel aerators, which include four 40-HP motors. Clarification The existing clarification system includes two 80-foot diameter pre -stressed units fitted with US Filter/Envirex Tow-Bro Unitube Headers for removal of the settled concentrated sludge material. The Tow-Bro system allows for rapid sludge removal of concentrated sludges with minimum agitation. The units are balanced hydraulically to allow sludge blankets to settle uniformly over the entire tank bottom. At the time of construction, the construction cost differential was fairly insignificant for a plant average daily flow between 1.0 MGD and 2.0 MGD. Therefore, the two units were designed and constructed for a plant average daily flow of 2.0 MGD, with a peak of 4.0 MGD and to allow for Class I Reliability with one unit out of service. Figure 2-5 illustrates the existing clarifiers. No work is anticipated for the expansion. Filtration The existing filters consist of three pre -fabricated traveling bridge filter units. Each unit is a US Filter/Davco Traveling Bridge Filter rated for 700,000 gpd. The first unit was installed in 1991 and is off-line until repairs are made. The two newer units were installed in 1998 with the plant expansion to 1.0 MGD. The Traveling Bridge Filters have many moving parts and are reported to constantly require maintenance. Figure 2-6 illustrates the existing filter systems. Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 2-8 July 2004 0 9 9 Po T F—r 24'p- lbj III III I jqi\ T Ot 3 FIGURE 2-4 EXISTING AERATION BASIN METZGER &WILLARD'INC. Civil - Environmental Engineers Tampa, Florida 33637 (813) 977-6005 0 0 0 F S \ a / I \ 5 � nYNLW •� / NaaPS Or T.- EVERY 71A BM \ -e• L` MJ EVFAv TD BNI I / .G'•n. I N-p• LOMI 1 � � '� '� � - n CENTRAL PRA I RAtlAL BARS r � i I — r.Y B. TYPICAL ---_--xr Yl ___--Tr------ _ --------------1------ I ♦• ♦• I >e I r r.e• Ian e• vyG• I%rr rr ry I B• PG e• Po m RANT E .--._.__`J GRAx Pwxi ov a TEE srAna b GG•.xr m[ s• xxs• ELBGa w To sr TE —IF'11--1-- — — — PamAna - - ` x.x.• REn1A91 xs• w ` 21• RUG (M4 FOUNDATION PLAN �tq 7 I r la-r aA Bean vnL \\//I `- 6Na1E11 nAL " BEAMS I SIaMLan / NEAGFA LGR PgNT W WWT ASSEMBLY I /i TM A BA�E YASrAAS Aw srArlW I I b Lb F B e• Pa `e• Puw Vaw .. .• _. ..�......�.. 11 I _.......... _ .. ra• n[o. 'ul e• 1EE u w ' r u• EIxNv -- — — — xr PWG (YA) $ !• TEE • ¢eon _ e• cn `x.• TEE TOP PLAN r Aa _ 5 � Imo• p O SE,JrT1 OM ..' .. 4 h St t �p MOI PgNT pf 4RWT XX\I\ x F FIGURE 2-5 EXISTING CLARIFIERS METZGER & WILLARD, INC. Civil • Environmental Engineers Tompo. Florida 33637 (813) 977-6005 Txxnw5147 - i�T• N 0A I - i1L ERUU RT�NI 1 � r xn�on r nx _ _ _ _ _ _ _ (W �� �) _ _ I_ 1 I �RFx♦ 6 y.�r-n.xn.. s •/ nrora.vcK Wv00 RTO %"I ft 7 L oonwr mJa/o� r.l i .•..•r• coxc yr t. ou1Mc rcoaR m.arxn. �� 11nBP,r ho OAVCO F%M {MT ft 3 Rl@LOQ � r R rm rw RL@11Oa � wx.w lxaw � n,a ma (rn1 sixrra wax nww a7 mnr u 1 ,gyp lrylrl I TOT& MU ft" —& CELL C ' Rr W xx VNIEI •+a iL1E11 Xa. RDN ol'D �I eA%D xE} WA Na DD M M.VP Z� M 11Et fiLL! M xP -T 1 MQ000 .R! ?.D 1.] M 1.o ! o T R MgooD W I t.! N! M ]M ! UMT D m= w ( !.! !.I M ]MI ! FIGURE 2-6 EXSITING EFFLUENT FILTER PLAN METZGER & WILLARD, INC. Civil x Environmental Engineers Tompa, Florido 33637 (813) 977-6005 The Authority is currently evaluating options for filtration capacity. With the original filter unit out of service, the remaining active filters have a rated capacity of 1.74 MGD Peak Flow or 0.97 MGD annual average daily flow. Prior to the flow reaching 0.97 MGD AADF, the Authority will need to have completed the rehabilitation or installation of additional filtration capacity. As a part of the filtration strategy, the Authority should consider the following options: 1. Rehabilitate the existing filter, providing an additional 700,00 0 gpd capacity. 2. Install a new filter, sized for the 700, 000 gpd capacity. 3. Install a new filter, sized for the future expansion that can be adopted into the future expansion strategy for the facility. The filtrate is continually monitored for Turbidity. In the event that turbidity concentrations increase above a pre -determined setpoint, the effluent is directed to a "reject water pond". The water in the reject water pond is re-routed through the plant for re -treatment prior to reuse. Chlorine Contact and Chlorination The existing chlorine contact chambers are a combination of one train of 5,000 gallon and two trains of 7,000 gallon pre -cast concrete basins, partially buried below ground surface. Figure 2-7 illustrates the existing chlorine contact chambers. The flow splits between the three separate trains and re -connects at the effluent pump station and flow measuring chamber. The Authority is currently in the process of switching from gaseous chlorine to a sodium hypochlorite mixture for chlorination. The effluent is chlorinated to "high-level disinfection" standards, meaning that total residual chlorine (TRC) of 1.0 mg/L is required in the effluent prior to re -use. The effluent is continually monitored for TRC and the effluent is automatically sent to the reject water pond if the TRC levels fall below standards. Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 2 - 12 July 2004 0 0 0 24' DEEP PVC / CONTROL Box -\ OF,P.P ..MR ALL 4' PIPE k VALVES TO —S BE REMOVED k REPLACED VAIN 6" PIPE h VALVES P P COHIROL BON EXISS. E. IW F D.1 P 5,000 9d' 5'D00 qw. CHLORINE CHLORINE 10- TEE &(2) 10-GV nALBASH CONTACT CONTACT g: BASIN 10" PE D.1 P .84- :E EXIST. 10 10- GATE VALVE NORMALLY CLOSEDD / ( •h II OVERFLOW I 1 1/2- TEE -//T'. (D.. ' .) INV. 38.9 CHLORINE SOLUTION PIPE r- . 0 IV CROSS -nDw II II CONTACTII II CBASH I ONTACT FLOW -I; F now II II7,000 qQL it II =4 CHLORINE CONTACT CONTACT mow 10. PE D.I.P I ININ k RACK C'S 1OPPLIIC am= ID-1iE 7 10- GV FIGURE 2- 7 EXISTING CHLORINE CONTACT CHAMBER METZGER &WILLARD, INC. Civil - Environmental Engineers T.-pcI. Fl orido 33637 (B13) 977-6005 • • Aerobic Diqesters The WWTP is equipped with two aerobic digesters for the treatment of the residual sludge. Each of the units is 60,000 CF for a total of 120,000 CF of aerobic digestion capacity. An alternative treatment program is planned for residuals management for this facility and is demonstrated in Technical Memorandum No. 2 of this study. Effluent Disposal and Reuse Effluent from the WWTP is currently stored in three existing ponds (two lined and one unlined) for use in citrus irrigation on an as -needed basis. The citrus irrigation is permitted for 800,000 gpd capacity. In addition, an on -site spray irrigation system, rated at 300,000 gpd, is also used as required. The expansion of the effluent disposal and reuse system is demonstrated in Technical Memorandum No. 3 of this study. Table 2-1 illustrates the existing design conditions for each of the treatment units within the wastewater treatment facility. Design conditions for the facility include organic as well as hydraulic loadings for the appropriate units. Technical Memorandum No. 1 WWTP Expansion Okeechobee Utility Authority 2 - 14 July 2004 • 0 Table 2-1. Unit Comparison — Design Conditions UNIT Aeration Clarifiers Aerobic Digesters Filters ITEM BOD Loading MLVSS Volume Oxygen Requirements Surface Loading Rate/Clarifier Solids Loading Rate/Clarifier Weir Overflow Rate/Clarifier Recycle Flow/Clarifier Pounds of Sludge Wasted Per Day, Based upon 0.8% Solids Volume/Day Total Sludge Retention Time Air Requirements at 30 scfm/1000 cf of volume Surface Loading Rate, Two units in Service DESIGN 2294 #/day 22,935 # MLVSS 167,303 cf provided 3726 #02/day 199 gpd/sf 10 # solids/day/sf 4080 gpd/If 500,000 gpd 225,180 # sludge/day 3607 cf sludge/day 52 days 3619 scfm 4.13 gpm/sf STANDARDS < 1000 gpd/sf < 35 # solids/day/sf < 20,000 gpd/If > 30 days < 5 gpm/sf Disinfection System Contact Time at AADF 33 minutes 15 minutes Contact Time at PDF 18 minutes 15 minutes Chlorine Use/Day, AADF 267 #/day (based upon gaseous chlorine use) Chlorine Feed Rate, AADF 20 ppm (based upon gaseous chlorine use) ! SECTION 3 EXISTING REGULATIONS Federal US EPA. 1974. Design Criteria for Mechanical. Electric and Fluid Svstem and Component Relibilitv — MCD — 05 — Provides the system design criteria to meet various reliability classifications. The Authority's facility provides secondary treatment with filtration, a high level disinfection and meets the requirements for Class I Reliability, as defined in this EPA document. Class I Reliability has many requirements to prevent possible treatment degradation. The following briefly summarizes many (but not all) of these requirements: Bar Screens: A backup unit shall be provided. The backup may be manual. Pumps: Backup pumps shall be provided for each set of pumps which performs the same function. The capacity shall be such that with any one pump out of servic e, the remaining pumps will have capacity enough to handle peak f lows. Aeration Basins: A backup basin is not required; however, at least two equal volume basins shall be provided. Blowers/Mechanical Aerators: Backup units shall be provided with a capacity such that with any one unit out of service, the remaining units will have enough capacity to aerate peak flows. The backup unit does not have to be installed. A minimum of two units must be installed. Clarifiers: A sufficient number of units of a size such that with the largest flow capacity unit out of service, the remaining units shall have a design flow capacity of at least 75 percent of the total design flow to that unit operation. Technical Memorandum No. 1 WWTP Expansion Okeechobee Utility Authority 3-1 July 2004 Disinfectant Contact Basins: A sufficient number of units of a size such that with the largest flow capacity unit out of service, the remaining units shall have a design flow capacity of at least 50 percent of the total design flow to that unit operatio n. Sludqe Holdino Tanks: Holding tanks are permissible as an alternative to component or system back up capability for components downstream of the tanks, if, the volume of the holding tank is based upon the expected time necessary to perform maintenance and repair of the component in question. Aerobic Sludqe Diqestion: A backup basin is not required. A minimum of two blowers shall be provided. Centrifuges: A sufficient number of centrifuges shall be provided to enable design sludge flow to be dewatered with largest unit out of service. Sludge holding tanks may be used as an alternative of redundant equipment. Electrical: For Class I Reliability, a continuity of operation shall be provided from two power sources (electrical service and on -site emergency generator). The emergency source shall be sufficient to operate all vital components, during peak wastewater flow conditions, together with critical lighting and ventilation. State The Florida Department of Environmental Protection (FDEP) regulates the construction and operation of wastewater treatment facilities in the State of Florida. The purpose is to prevent the potential degradation of the water and air quality. Regulations issued as Florida Administrative Codes (FAC) concerning the construction and operation of treatment facilities include the following: 62-602: Drinkinq Water and Domestic Wastewater Treatment Plant Operators — Provides the requirements for operator licensure, including the education and experience necessary to be a licensed operator. Technical Memorandum No. 1 Okeechobee Utility Authorit y WWTP Expansion 3-2 July 2004 M62-610: Reuse of Reclaimed Water and Land Application — Defines reuse and land application of wastewater. Provides a comprehensive and detailed set of requirements for design and operational criteria for reuse and land application sites. 62-620: Wastewater Facilitv and Activities Permittinq — Provides the procedures necessary to obtain a permit to construct, modify or operate a wastewater facility which discharges wastes into waters of the State or which will reasonably be expected to be a source of water pollution. The rule states that "Any portion of the wastewater facility ... which relates to reuse or disposal of reclaimed water shall not be constructed or modified without a wastewater permit". The rule also provides the recordkeeping requirements for each facility. 62-650: Water Qualitv Based Effluent Limitations — Provides the effluent limitation that may be more stringent than a 'Treatment Based Effluent Limitation (TBEL)" to ensure water quality standards in a receiving water body are not violated. A WQBEL is used to determined the assimilative capacity of a water body. 62-699.310: Classification and Staffinq of Plants — Provides for a Category III, Extended Aeration Process and Oxidation Ditches with or without Filters, Class B (2.0 — 8.0 MGD), the operator coverage for the facility is as follows: Class C or higher — 16 hours/day, 7 days/week Chief operator — Class B or higher 62-304: Total Maximum Dailv Loads (05/24/01) — Provides a Total Maximum Daily Load (TMDL) for Lake Okeechobee for total phosphorus of 140 metric tons, including atmospheric deposition. This goal for phosphorus will reduce phosphorus levels in the Lake to a pre -developed level that will reduce eutrophication in the Lake. 62-600: Domestic Wastewater Facilities — Provides the minimum standards for the design of domestic wastewater facilities and establishes the minimum treatment and disinfection requirements for the operation of domestic wastewater facilities. The rule references Florida Statute 403.021(2), the Florida Air and Water Pollution Control Act, "No wastes are to be discharged to any waters of the state without first being given the Technical Memorandum No. 1 Okeechobee UtilityAuthority Y WWTP Expansion 3-3 July 2004 degree of treatment necessary to protect the beneficial uses of such water." Type I facilities are defined in the rule as any facility with a flow capacity equal to or over 500,000 gallons. 62-600.400: Design Requirements — The rule requires that the design of a wastewater treatment facility be "in accordance with sound engineering practice". Facilities shall "efficiently and reliably' meet required effluent limitations. All facilities are to be designed to minimize adverse effects from odors, noise, aerosol drift and lighting. Facilities are required to be enclosed within a fence or within other features that discourage the entry of animals and unauthorized persons. Facilities should be protected from the impacts of a 100 year flood. 62-600.405: Planning for Wastewater Facilitv Expansion — Provides for the timely planning, design, and construction of wastewater facilities necessary to provide proper treatment and reuse or disposal of wastewater and residuals. 62-600.420: Minimum Treatment Standards — Treatment Based Effluent Limitations — Provides for the minimum levels of treatment based upon the ultimate disposal of the treated product, as follows: TABLE 3-1. MINIMUM TREATMENT STANDARDS CBOD5 TSS Secondary Treatment Surface Water Disposal (excluding ocean outfalls) 20 20 Surface Water Disposal via Ocean Outfall Coastal Open Ocean 30 30 Reuse, Land Application, Groundwater Discharge (except for 20 20 underground injection well) Groundwater Discharge by Underground Injection Well Class I wells to Class G-IV waters 20 20 Class V wells into Class G-II waters < 20 < 20 Additional levels of treatment are required for reclaimed water use including the following: 1. Shall receive High level disinfection, TSS shall be as required to meet the high level disinfection requirements 2. Shall meet the standards without a mixing zone. 3. Shall have a total nitrogen less than or equal to 10 mg/L. Technical Memorandum No. 1 Okeechobee Utility Authority tY WWTP Expansion 3-4 July 2004 • • :7 4. Shall meet the requirements for primary and secondary drinking water standards. 62-600.430: Water Qualitv Based Effluent Limitations — May be required to provide additional treatment to satisfy water quality standards for receiving surface waters and/or ground waters. WQBELs are determined by the FDEP and are required to be met after disinfection. WQBELs are determined by the "application of accepted scientific methods". 62-600.440: Disinfection — Two types of disinfection are defined and include the following: 1. Basic: a. Fecal coliform count is less than 200 per 100 mL of effluent sample. b. A residual of 0.5 mg/L or higher is measured after 15 minutes of contact time at peak hourly flow. 2. High Level: a. Total Suspended Solids in the effluent is low enough to maximize the disinfection effectiveness. Fecal coliform values in the effluent shall be below detectable levels. b. A residual of 1.0 mg/L or higher is measured after 15 minutes of contact time at peak hourly flow. 62-600.445: DH — pH shall be measured in the effluent in the range of 6.0 to 8.5 units, which provides a neutral product (neither acidic nor basic). Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 3-5 July 2004 • SECTION 4 CURRENT AND FUTURE FLOWS AND QUALITY Existinq Quantitv In September 1998, the existing plant was placed on-line. At that time, the older (1985) contact stabilization activated sludge (CSAS) facility was taken off-line for maintenance and repairs. Currently, the existing CSAS facility remains off-line. Historical flows at the existing WWTP are shown in Table 4-1 (January 1986 through June 2004). Future Quantity Projected flows were developed for the Wastewater Plan, based upon system growth anticipated from infill, inclusion of existing package plants that are removed from service and collection system expansion. Growth is the area appears to be increasing as evidenced by developer agreement requests and the development of sewer systems for areas adjacent to the Lake. The system expansion schedule and projected flows are shown in Table 4-2 and illustrated in F1 gure 4-1. FDEP Rule 62-600.405(8) FAC presents the requirements for the planning, design, permitting, construction and activation of wastewater treatment plants, based upon the flows into the facility. The requirements for the expansion activities are as follows: 1. If the WWTP capacity will be equaled or exceeded within five years, the planning and preliminary engineering of the expanded facility shall have begun. 2. If the WWTP capacity will be equaled or exceeded within four years, the development of the plans and specifi cations shall have begun. 3. If the WWTP capacity will be equaled or exceeded within three years, the complete construction permit application shall be submitted to FDEP (i.e., the design is complete). Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 4-1 July 2004 TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY MONTHLY 3-MONTH RUNNING ANNUAL 3 MONTH AVERAGE AS % DATE AVERAGE, MGD AVERAGE, MGD AVG, MGD DESIGN CAPACITY Jan-86 0.227 - 0.227 - Feb-86 0.186 - 0.207 - Mar-86 0.182 0.198 0.198 33.1 Apr-86 0.194 0.187 0.197 31.2 May-86 0.208 0.195 0.199 32.4 Jun-86 0.233 0.212 0.205 35.3 Jul-86 0.223 0.221 0.208 36.9 Aug-86 0.251 0.236 0.213 39.3 Sep-86 0.382 0.285 0.232 47.6 Oct-86 0.400 0.344 0.249 57.4 Nov-86 0.244 0.342 0.248 57.0 Dec-86 0.290 0.311 0.252 51.9 Jan-87 0.308 0.281 0.258 46.8 Feb-87 0.279 0.292 0.266 48.7 Mar-87 0.292 0.293 0.275 48.8 Apr-87 0.256 0.276 0.281 45.9 May-87 0.252 0.267 0.284 44.4 Jun-87 0.244 0.251 0.285 41.8 Jul-87 0.261 0.252 0.288 42.1 Aug-87 0.238 0.248 0.287 41.3 Sep-87 0.230 0.243 0.275 40.5 Oct-87 0.254 0.241 0.262 40.1 • Nov-87 0.342 0.275 0.271 45.9 Dec-87 0.314 0.303 0.273 50.6 Jan-88 0.299 0.318 0.272 53.1 Feb-88 0.340 0.318 0.277 52.9 Mar-88 0.332 0.324 0.280 53.9 Apr-88 0.259 0.310 0.280 51.7 May-88 0.265 0.285 0.282 47.6 Jun-88 0.255 0.260 0.282 43.3 Jul-88 0.276 0.265 0.284 44.2 Aug-88 0.345 0.292 0.293 48.7 Sep-88 0.270 0.297 0.296 49.5 Oct-88 0.282 0.299 0.298 49.8 Nov-88 0.328 0.293 0.297 48.9 Dec-88 0.269 0.293 0.293 48.8 Jan-89 0.313 0.303 0.295 50.6 Feb-89 0.265 0.282 0.288 47.1 Mar-89 0.324 0.301 0.288 50.1 Apr-89 0.288 0.292 0.290 48.7 May-89 0.281 0.298 0.291 49.6 Jun-89 0.284 0.284 0.294 47.4 Jul-89 0.311 0.292 0.297 48.7 Aug-89 0.359 0.318 0.298 53.0 Sep-89 0.369 0.346 0.306 57.7 Oct-89 0.362 0.363 0.313 60.6 Nov-89 0.319 0.350 0.312 58.3 Dec-89 0.322 0.334 0.316 55.7 • Table 4-1 4-2 7/16/2004 0 TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY DATE Jan-90 Feb-90 Mar-90 Apr-90 May-90 Jun-90 J u I-90 Aug-90 Sep-90 Oct-90 Nov-90 Dec-90 Jan-91 Feb-91 Mar-91 Apr-91 May-91 Jun-91 Jul-91 Aug-91 Sep-91 Oct-91 Nov-91 Dec-91 Jan-92 Feb-92 Mar-92 Apr-92 May-92 Jun-92 Jul-92 Aug-92 Sep-92 Oct-92 Nov-92 Dec-92 Jan-93 Feb-93 Mar-93 Apr-93 May-93 Jun-93 J u I-93 Aug-93 Sep-93 Oct-93 Nov-93 Dec-93 Table 4-1 MONTHLY AVERAGE, MGD 0.348 0.295 0.275 0.280 0.314 0.279 0.251 0.335 0.332 0.409 0.302 0.259 0.263 0.333 0.410 0.451 0.407 0.292 0.340 0.339 0.435 0.374 0.380 0.354 0.438 0.407 0.250 0.262 0.263 0.586 0.457 0.520 0.517 0.397 0.463 0.430 0.481 0.503 0.529 0.515 0.513 0.336 0.316 0.403 0.449 0.457 0.326 0.291 3-MONTH AVERAGE, MGD 0.330 0.322 0.306 0.283 0.290 0.291 0.281 0.288 0.306 0.359 0.348 0.323 0.275 0.285 0.335 0.398 0.423 0.383 0.346 0.324 0.371 0.383 0.396 0.369 0.391 0.400 0.365 0.306 0.258 0.370 0.435 0.521 0.498 0.478 0.459 0.430 0.458 0.471 0.504 0.516 0.519 0.455 0.388 0.352 0.389 0.436 0.411 0.358 RUNNING ANNUAL AVG, MGD 0.319 0.322 0.318 0.317 0.320 0.319 0.314 0.312 0.309 0.313 0.312 0.307 0.300 0.303 0.314 0.328 0.336 0.337 0.344 0.345 0.353 0.350 0.357 0.365 0.379 0.386 0.372 0.357 0.345 0.369 0.379 0.394 0.401 0.403 0.410 0.416 0.419 0.427 0.451 0.472 0.493 0.472 0.460 0.450 0.445 0.450 0.438 0.427 4-3 3 MONTH AVERAGE AS % DESIGN CAPACITY 54.9 53.6 51.0 47.2 48.3 48.5 46.9 48.1 51.0 59.8 57.9 53.9 45.8 47.5 55.9 66.3 70.4 63.9 57.7 53.9 61.9 63.8 66.1 61.6 65.1 66.6 60.8 51.1 43.1 61.7 72.6 86.8 83.0 79.7 76.5 71.7 76.3 78.6 84.1 85.9 86.5 75.8 64.7 58.6 64.9 72.7 68.4 59.7 7/16/2004 0 • TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY DATE Jan-94 Feb-94 Mar-94 Apr-94 May-94 Jun-94 J u I-94 Aug-94 Sep-94 Oct-94 Nov-94 Dec-94 Jan-95 Feb-95 Mar-95 Apr-95 May-95 Jun-95 J u I-95 Aug-95 Sep-95 Oct-95 Nov-95 Dec-95 Jan-96 Feb-96 Mar-96 Apr-96 May-96 Jun-96 Jul-96 Aug-96 Sep-96 Oct-96 Nov-96 Dec-96 Jan-97 Feb-97 Mar-97 Apr-97 May-97 Jun-97 J u I-97 Aug-97 Sep-97 Oct-97 Nov-97 Dec-97 Table 4-1 MONTHLY AVERAGE, MGD 0.314 0.374 0.337 0.305 0.297 0.254 0.300 0.407 0.366 0.478 0.583 0.500 0.500 0.454 0.453 0.422 0.400 0.430 0.422 0.476 0.435 0.641 0.485 0.479 0.511 0.535 0.567 0.541 0.463 0.618 0.659 0.465 0.492 0.543 0.532 0.563 0.583 0.620 0.615 0.614 0.573 0.579 0.682 0.567 0.660 0.608 0.648 0.744 3-MONTH AVERAGE, MGD 0.310 0.326 0.342 0.339 0.313 0.285 0.284 0.320 0.358 0.417 0.476 0.520 0.528 0.485 0.469 0.443 0.425 0.417 0.417 0.443 0.444 0.517 0.520 0.535 0.492 0.508 0.538 0.548 0.524 0.541 0.580 0.581 0.539 0.500 0.522 0.546 0.559 0.589 0.606 0.616 0.601 0.589 0.611 0.609 0.636 0.612 0.639 0.667 RUNNING ANNUAL AVG, MGD 0.413 0.402 0.386 0.368 0.350 0.344 0.342 0.343 0.336 0.337 0.359 0.376 0.392 0.398 0.408 0.418 0.426 0.441 0.451 0.457 0.463 0.476 0.468 0.466 0.467 0.474 0.484 0.494 0.499 0.514 0.534 0.533 0.538 0.530 0.534 0.541 0.547 0.554 0.558 0.564 0.573 0.570 0.572 0.580 0.594 0.600 0.609 0.624 4-4 3 MONTH AVERAGE AS % DESIGN CAPACITY 51.7 54.4 56.9 56.4 52.2 47.6 47.3 53.4 59.6 69.5 79.3 86.7 87.9 80.8 78.2 73.8 70.8 69.6 69.6 73.8 74.1 86.2 86.7 89.2 81.9 84.7 89.6 91.3 87.3 90.1 96.7 96.8 89.8 83.3 87.1 91.0 93.2 98.1 101.0 102.7 100.1 98.1 101.9 101.6 106.1 101.9 106.4 111.1 7/16/2004 9 TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY DATE Jan-98 Feb-98 Mar-98 Apr-98 May-98 Jun-98 Jul-98 Aug-98 Sep-98 Oct-98 Nov-98 Dec-98 Jan-99 Feb-99 Mar-99 Apr-99 May-99 Jun-99 Jul-99 Aug-99 Sep-99 Oct-99 Nov-99 Dec-99 Jan-00 Feb-00 Mar-00 Apr-00 May-00 Jun-00 Jul-00 Aug-00 Sep-00 Oct-00 Nov-00 Dec-00 Jan-01 Feb-01 Mar-01 Apr-01 May-01 Jun-01 Jul-01 Aug-01 Sep-01 Oct-01 Nov-01 Dec-01 Table 4-1 MONTHLY AVERAGE,MGD 0.798 0 886 0.806 0.697 0.608 0.549 0.502 0.509 0.539 0.448 0.522 0.500 0.548 0.647 0.663 0.595 0.492 0.668 0.560 0.545 0.747 0.701 0.611 0.555 0.593 0.643 0.569 0.509 0.481 0.476 0.494 0.446 0.564 0.546 0.532 0.483 0.570 0.591 0.678 0.646 0.658 0.704 0.724 0.648 0.780 0.702 0.649 0.567 3-MONTH AVERAGE, MGD 0.730 0.809 0.830 0.796 0.704 0.618 0.553 0.520 0.517 0.499 0.503 0.490 0.523 0.565 0.619 0.635 0.583 0.585 0.573 0.591 0.617 0.664 0.686 0.622 0.586 0.597 0.602 0.574 0.520 0.489 0.484 0.472 0.501 0.519 0.547 0.520 0.528 0.548 0.613 0.638 0.661 0.669 0.695 0.692 0.717 0.710 0.710 0.639 RUNNING ANNUAL AVG, MGD 0.642 0.665 0.680 0.687 0.690 0.688 0.673 0.668 0.658 4-5 0.645 0.634 0.614 0.593 0.573 0.561 0.553 0.543 0.553 0.558 0.561 0.578 0.599 0.606 0.611 0.615 0.614 0.607 0.599 0.599 0.583 0.577 0.569 0.554 0.541 0.534 0.528 0.526 0.522 0.531 0.542 0.557 0.576 0.595 0.612 0.630 0.643 0.653 0.660 3 MONTH AVERAGE AS % DESIGN CAPACITY 121.7 134.9 138.3 132.7 1173 103.0 92.2 86.7 32.3 45.3 45.7 44.5 47.6 51.4 56.3 57.7 53.0 53.2 52.1 53.7 56.1 60.4 62.4 56.6 53.3 54.3 54.7 52.2 47.2 44.4 44.0 42.9 45.6 47.2 49.8 47.3 48.0 49.8 55.7 58.0 60.1 60.8 63.2 62.9 65.2 64.5 64.6 58.1 7/16/2004 0 0 TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY MONTHLY 3-MONTH DATE AVERAGE, MGD AVERAGE, MGD Jan-02 0.601 0.606 Feb-02 0.612 0.593 Mar-02 0.567 0.593 Apr-02 0.533 0.571 May-02 0.483 0.528 Jun-02 0.493 0.503 Jul-02 0.618 0.531 Aug-02 0.552 0.554 Sep-02 0.660 0.610 Oct-02 0.608 0.607 Nov-02 0.622 0.630 Dec-02 0.735 0.655 Jan-03 0.777 0.711 Feb-03 0.729 0.747 Mar-03 0.711 0.739 Apr-03 0.660 0.700 May-03 0.638 0.670 Jun-03 0.696 0.665 Jul-03 0.656 0.663 Aug-03 0.815 0.722 Sep-03 0.766 0.746 Oct-03 0.716 0.766 Nov-03 0.696 0.726 Dec-03 0.666 0.693 Jan-04 0.685 0.682 Feb-04 0.716 0.689 Mar-04 0.683 0.695 Apr-04 0.658 0.686 May-04 0.631 0.657 Jun-04 0.616 0.635 Table 4-1 RUNNING ANNUAL 3 MONTH AVERAGE AS % AVG, MGD DESIGN CAPACITY 0.662 55.1 0.664 53.9 0.655 53.9 0.645 51.9 0.631 48.0 0.613 45.7 0.604 48.3 0.596 50.4 0.586 55.5 0.579 55.2 0.576 57.3 0.590 59.5 0.605 64.7 0.615 67.9 0.627 67.2 0.637 63.6 0.650 60.9 0.667 60.4 0.670 60.3 0.692 65.7 0.701 67.8 0.710 69.6 0.716 66.0 0.711 63.0 0.703 62.0 0.702 62.6 0.699 63.2 0.699 62.3 0.699 59.8 0.692 57.7 4-6 7/16/2004 0 0 0 TABLE 4-2. PROJECTED FLOWS FOR OUA WWTP (2003-2016) Taylor Creek Isles Ousley Infill Treasure Island SW (160 units) SE (1000 units) NE (300 units) Misc Projects Other Growth TOTAL for YEAR, GPD AVERAGE DAY, MAXIMUM DAY, MAX -MO . Ertd,of Year 2003 2004 2005 2006 '2007 2000. 20009 2010 2011 2012 2013 2014 2015 2016 122,500 122,500 10,000 10,000 10,000 10,000 112,000 223,000 50,000 30,000 10,000 25,000 37,500 50,000 62,500 50,000 25,000 25,000 50,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 19,150 22,691 27,696 33,563 43,040 47,491 51,116 54,269 56,875 58,922 61,020 63,171 65,375 141,650 200,191 234,696 379,063 178,040 144,991 126,116 104,269 81,875 83,922 86,020 88,171 90,375 766,000 907,650 1,107,841 1,342,537 1,721,601 1,899,641 2,044,632 2,170,748 2,275,016 2,356,892 2,440,814 2,526,834 2,615,005 2,705,380 1,149,000 1,406,858 1,717,154 2,080,933 2,668,481 2,944,443 3,169,179 3,364,659 3,526,275 3,653,182 3,783,262 3,916,593 4,053,258 4,193,339 7/16/2004 • • FIGURE 4-1. PROJECTED WASTEWATER FLOWS, 2003 - 2016 3,000,000 2,500,000 2,000,000 G (L 0 if 1,500,000 O J LL 1,000,000 500,000 0 1 1 1 1 1 1 1 1 M 'T U) O 1- co O_ _ N _M d' �_ CO O O O O O O O O O O O O O O O O O O O O O N N N N N N N N N N N N N N END OF YEAR • The WWTP was originally designed to be expanded in 1 MGD increments. Based upon the projected flows for 2004 — 2016, the Authority should consider a 2 MGD expansion at this time to meet the requirements of 62-600.4 50(8) FAC. As a part of this analysis, 2 MGD, 3 MGD and a 4 MGD alternatives are considered as shown in the following sections. From the projected flows, and based upon the existing wastewater treatment plant design, the characteristics presented in Table 4-3 are being used in the development of the expanded facility. Anticipated Qualitv It is anticipated that the quality of the influent waste stream at the OUA wastewater treatment facility will remain fairly consistent, provided no new industries develop in the area that could impact the quality of the waste. Table 4-3 summarizes the anticipated quality. TABLE 4-3. CHARACTERISTICS OF FLOW AND STRENGTH OF WASTE. FLOW CHARACTERISTICS DESIGN Peak Daily Flow PDF MGD 4.00 Maximum Monthly Flow MMF MGD 3.00 Annual Average Daily Flow AADF MGD 2.00 Minimum Flow MF MGD 0.80 Peak Hourly Flow PHF MGD 4.00 INFLUENT AND EFFLUENT CHARACTERISTICS INFLUENT EFFLUENT Carbonaceous Biochemical Oxygen Demand CBODS mg/L 300 < 10 Total Suspended Solids TSS mg/L 250 < 10 Total Nitrogen TN mg/L 40 < 3 Total Phosphorus TP mg/L 10 < 2 Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 4-9 July 2004 • SECTION 5 POTENTIAL TREATMENT STRATEGIES The proposed wastewater treatment facility consists of the following major components: Master Pump Station Headworks Aeration Basi n Clarifiers Filters Chlorine Contact Chamber and Chlorination System Aerobic Digesters/Sludge Processing/Disposal Effluent Disposal The major components are further described herein, with the exception of the Aerobic Digesters/Sludge Processing, which is the subject of Technical Memorandum No. 2, dated July 2004. Effluent disposal is discussed in Technical Memorandum No. 3, dated July 2004. Options have been developed and are summarized below. Opinions of cost have been developed for each of the alternatives. An analysis and recommendation is provided in Section 7 of this memorandum. Master Pump Station A new Master Pump Station (MPS) is proposed. All flow to the wastewater treatment plant is pumped by many small in -town pump station and two large regional facilities (SE2 and NW15). With all of the flow to the plant being pumped and none by gravity, the plant sees hydraulic surges throughout the day. The MPS will act as a flow equalization system to the facility and will prevent hydraulic overloading into the facility. Variable frequency drive units on the pumps will attenuate the flow into the facility by operating along with the influent flow into the station. By placing the MPS in the location shown in Figure 5-1, the following advantages occur: 1. Reduces head conditions on pumps in -town that are pumping to the facility — providing for more efficient use of the pumps. 2. Allows the original influent force main and static screens to remain for an emergency bypass condition. Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5-1 June 2004 • EXIST 18" D.I. FM EX. 4" WM CL200 PVC i FROM ECKERDS i EXISTING ADMIN. BLDG. E 11 `� PROPOSED 18' MASTER t8' PUMP STATION ■ P.P r--I LPROPOSED HEADWORKS ALTERNATIVE MASTER PUMP - I STATION LOCATION EX. (2) 18" GV / EXISTING ASPHAL �l HEADWORKS BYPASS LINE DA------------------�----------------- g 18" RS EX r-T EX. 2" FM ' _4' WM —— I PVC J I FM �" 1 I I EX. 1 (A I m I X I I �1 � 31 1 /2" WM a 1 ;< I " xI WI II I IfILL RSS I II EX. 16" RSS ---IJ I 1 1 I ( L------------a I ' FIGURE 5-1 PROPOSED MASTER PUMP STATION & HEADWORKS LOCATION METZGER & WILLARD, INC. Civil • Environmenfol Engineers Tampa. Florida 33637 (813) 977-6005 • 3. Headworks elevation is determined "locally" at the wastewater treatment plant and the headworks elevation will not affect the hydraulic conditions on the in - town pump stations. The MPS design shall incorporate a two -vault configuration so that routine maintenance and cleaning can be performed, as shown in Figure 5-2. An option is to place the MPS downstream of the headworks. The MPS could then also receive the filter backwash, etc., and replace the on -site plant drain pump station. An advantage is that the headworks could then be constructed at grade making the facility more accessible for operations and maintenance. The headworks would be designed to accommodate the potential hydraulic peaks to the facil ity. Based upon the layout provided in Figure 5-2, the opinion of probable construction cost for the MPS is $500,000, including a 30 percent contingency. The construction costs for the MPS are the same for each location; however, by placing the MPS before the headworks, the life expectancy of the upstream pump stations may be increased. The pump stations have less head to pump against to bring flow from the downtown area to the wastewater treatment facility. Headworks The purpose of the headworks is to provide preliminary treatment to the wastestream by removing non -organic materials from the wastestream that can potentially harm equipment (sticks, metal objects, sand/grit) as well as may deposit in the facility reducing the volume of the units. A typical headworks structure is illustrated in Figure 5-3. Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5-3 June 2004 • — IS" INFLUENT LINE PUM PUM PUN PUM IS' DIP EFFLUENT LINE NOTE: ODOR CONTROL TO BE PROVIDED. APPROXIMATE DIMENSIONS OF PUMP STATION IS 20a201 LO. ACCESS COVER S' CHECK VALVE (TYPICAL OF 4) E' DATE VALVE ACCESS COVER //(T�PICAL OF t) TOP OF CONCRETE EL J6.S0 ' ` \ GROUND SURFACE EL 3150 IS* INFLUENT LIME — — 18' DIP EFFLUENT LINE � S ALARM EL 27.00 LAC PUMP 2 ON EL. 29.00 � a aI I uc PUMP , ON n. xaoo I LEAD PUMP ON EL. 20.00 BOOR EL 19.00 �~ �t ,. r .. • w ..� I ALL PUMPS OFT EL 17.00 ... I . ROd! EL 10.00 ELEVATION FIGURE 5-2 MASTER PUMP STATION METZGER & WILLARD, INC. Civil • Environmentol Engineers Tampa, Florida 33637 (813) 977-6005 0 a»w1¢ ,o aRPs,ER� r'r------- 7.: u I LI `/1WMW NANORA ("P.) NOTE PROCESSES LLUSTRATED- ACUAGlARO SCREEN t PISTA-GRIT COLLECTOR MECNAMCk STOP CATE (Tro1EAE of �) 9"19N OR \ ` EnST. MADE FIGURE 5-3 HEADWORKS STRUCTURE METZGER & WILLARD, INC. Civil • Environmental Engineers Tom Pa. Florida 33637 (613) 977-6005 L-1 11 Sand and grit may scour concrete and eventually cause damage by exposing metal reinforcing materials. The influent flow is measured in the headworks; and, influent flow quality is also monitored at this point. Appendix A contains manufacturer's data. SCREENING: Mechanically -cleaned bar screens are a reliable method of removing large inorganic materials from the wastestream. The units are self-cleaning and can remove particles down to 2 mm. The screenings are washed to remove organics which flow back to the wastestream. The screenings are then dewatered and placed in a container for disposal. Several equipment options are available and inc Jude the following. Figure 5-4a. Lo-Flow Screening Unit Technical Memorandum No. 1 WWTP Expansion Jones + Attwood. Inc., Lo-Flow Screening Unit: The Lo-Flow unit is a complete screening system designed for smaller treatment works. The units are constructed of 316L S tatinless Steel and screen particles larger than % of an inch in diameter. The unit is provided with a "Washpactor" which washes the screened materials, dewaters and conveys the material to a collection container for disposal. Organic materials are washed from the screenings and are returned to the treatment plant. Odors are low since organics are returned to the wastestream. The budget price for a Lo-Flow Screening Unit with Washpactor is $150,000 for the equipment or $225,000 installed. The Lo-Flow unit is illustrated in Figure 5-4a, with the Washpactor depicted in Figure 5-4b. Okeechobee Utility Authority 5-6 June 2004 • Pj '�2 Wached 3ereenlgge .r Outlet Gt�ute 'i Screened PWt 4 Intro Peato ComDectar xowr _____ _. _'. Hf61t Speed TmyeIIe Prooeea Water Ihatq un.,e xotor Figure 5-4b. Washpactor MTS Spirac CS500 Screen: The Spirac CS 500 is an in - channel shaft -less screw screening, conveying, dewatering and compacting system. The standard material is 304SS with a 316SS option. Based upon prior experience, the Authority should require the 316SS option. The unit Pivots out of the flow channel for inspection. The unit can be fitted with a screening plate that will stop all materials larger than 1/8 inch, 3/16 inch or'/a inch. The CS 500 with bagger and control panel budge price is $48,000 for equipment or $72,000 installed (304 SS). For the 316SS, an increase of 25 percent in budget price is assumed or $60,000 for equipment or $90,000 installed. Figure 5-5 illustrates the CS 500 unit. Technical Memorandum No. 1 WWTP Expansion Okeechobee Utility Authority 5-7 June 2004 n 9 • MTS Spirac ST Screen: The ST Screen is a stair - shaped in -channel screening unit. This small compact unit has a capacity of approximately 3100 gpm with minimal headloss through the unit. The unit is capable of stopping materials larger than '/4 inch in diameter. The equipment cost is $50,000, with an installed budget price of $75,000. Figure 5-6 illustrates the ST Screen. --Wf4m ^ .s- Figure 5-6. Spirac ST Screen Parkson Aouaguard: The Aquaguard is a self-cleaning in channel device designed for a 15 - 20 year life cycle. The unit fits in channels from 1-foot to 9- feet in width, with size determined by the anticipated flow through the unit. The filter elements are staggered to prevent blocking. The Aquaguard travels at a rate of approximately 7 feet per minute and removes material 1/4 inches and larger. The design of the unit allows for complete cleaning of the unit. The screen is used with a Spiral Klean Screenings washer which significantly reduces the organic content of wet screenings. The Spiral Klean is a high-speed agitator using water and air to clean the screenings. From the Spiral Klean unit, the screenings enter a Rotopress Screenings Compactor, where the screenings are dewaters and reduced in volume up to 75 percent. The solids are between 40 and 50 percent dry. The unit is provided with a spray header for cleaning. The budget price for an Aquaguard is $61,000 for 304SS equipment or $91,500 installed. For 316SS, the budget price is $70,150 for equipment or $105,225 installed. Again, Technical Memorandum No. 1 WWTP Expansion Okeechobee Utility Authority 5-8 June 2004 • because of prior experience the Authority should require the 316SS option. Figure 5-7 illustrates the Aquaguard system. GRIT REMOVAL: Grit removal at a wastewater treatment plant protects mechanical equipment and concrete from excessive wear and abrasion from the sand, and other heavy particles that are introduced into the wastestream throughout the collection system. In Florida, a fine particle sand, known as "sugar sand", is difficult to remove and causes considerable damage. By removing the grit prior to treatment, grit does not impact the volume of the facili ty. The grit is removed typically by developing an hydraulic vortex within the flow stream, which causes the grit to settle to the bottom of the unit. The grit is then pumped to a grit washer to remove the organics, dewatered and contained for disposal at a landfill. The wash water is placed back into the treatment process. • Typical grit systems evaluated include the following: • 1. Eutek Systems, Inc., Headcell with Slurry Cup and Grit S nail 2. Jones + Attwood, Inc., Jeta-Grit 3. Smith & Loveless, Inc., PISTA-Grit Concentrator 4. Walker Process 5. Fluidyne Hydro -Grit Each system uses a vortex flow to remove grit from suspension and collect for disposal. Descriptions of each system follow. Eutek Headcell: Figures 5-8 and 5-9 illustrate a typical Eutek system for grit removal. The Headcell is a modular unit containing multiple trays for the removal of grit larger than or equal to 50 microns. The unit experiences minimal headloss (less than 12-inches) when operating. The unit has a large surface area but occupies a small footprint. The units come in 6-, 9- and 12-foot diameters depending upon flow. The grit unit itself has no moving parts. The unit is designed to prevent short-circuiting. The col lected grit is pumped to a Eutek Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5-9 June 2004 T Ls a�t5� �• 31 1 C t FIGURE 5-8 EUTEK HEADCECI METZGER & WlL- L RD, INC. C/O - Environmental Engineers Tampa. Florida 33637 (813) 977-6005 _it FIGURE 5-9 EUTEK SLURRY CUP AND GRIT SNAIL METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, Florida 33637 (813) 977-6005 Slurry Cup, which is a grit classification and separation mechanism. The Slurry Cup washes the grit, which minimizes organic content of the grit reducing objectionable odors and reducing volume of material. The unit is reported to remove more than 95 percent of abrasives which increases downstream solids handling capacity. The unit is simple to operate and easy to install. The Slurry Cup is meant to be operated with the Eutek Grit Snail, which captures, removes and dewaters settleable high -density solids. The unit discharges clean, low odor solids at 60 percent total solids with less than 20 percent volatile solids. The unit is slow -moving with stepped cleats which captures solids and lifts at a rate of 1 — 5 feet per minute. The clarified water is sent back to the headworks. Dewatered grit is carried to the top where it is scraped off the belt and falls into a disposal container. The unit has no metal to metal contact on belt housing and components. A variable drive adjusts the speed of the unit with grit load. The unit is capable of moving 1 —10 cy/hour of grit. Based upon the anticipated flows at the wastewater treatment plant and the . modular unit placed in a cast -in -place concrete tank, the budget price for equipment is $172,000, plus installation or $258,000 total. Jones + Attwood. Inc.. Jeta-Grit: The Jeta-grit is a compact, circular trap located in the mainstream of the inlet system. The Jeta-Grit is illustrated in Figure 5-10. Effluent enters tangentially and flows around the tank and exits parallel to the inlet. Grit settles in the lower hopper and is transferred by a pumping system to washing, classification and dewatering processes. Impeller speed is used to control the grit classifying effect in the unit. Grit extraction is through use of an airlift. As an Technical Memorandum No. 1 WWTP Expansion Figure 5-10. Jeta-Grit System Okeechobee Utility Authority 5 - 12 June 2004 • alternative, a grit pump can be used. The unit can be a steel fabricated (stand alone) unit or an in channel unit. The screw classifier is packaged, free-standing. This unit receives grit and water into a receiving header box. An archimedian screw rotates and solids are transported up an incline, where they dewater prior to dropping into a container for disposal. The budget price for the equipment is $65,000 or $97,500 installed for carbon steel. For 316L Stainless Steel, the budget price is $80,000 for the equipment or $120,000 installed. Smith & Loveless. Pista-Grit: Figure 5-11 illustrates a typical Pista-grit system. The unit can be installed within a 316 stainless steel structure as a modular unit P'sQm Q�t CGrlooribtl�r DwmWW c�ueo�asdt� Grit ink ova aaso.wt�•� Wda and raidusl agKdW ue racyclBd 10 mlct chaacl. Turbo PWP Plan®MOMber Figure 5-11. Pista-Grit or installed within a cast -in - place concrete unit. The Pista-grit system is provided complete with appropriate drives, pumps, dewatering screw conveyors and controls. The unit operates in a similar fashion to the Eutek System. The budget prices for the Pista-grit equipment are as follows: TABLE 5-1. EQUIPMENT COSTS — PISTA-GRIT SYSTEM 1. Model 4.OA 316 SS Unit with 316 SS Modular Unit Equipment $ 111,500 Installation 55,750 TOTAL $ 167,250 2. Model 4.OA Concrete Outer Tank with 316 SS Internal Unit Equipment $ 83,500 Installation 41,750 TOTAL $ 125,250 Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 13 June 2004 ss ling Walker Process Rolling Grit:, Figure 5-12 illustrates the Walker roceuses air to Grit — Grit Removal System. The unit is placed into a square set up a vertical vortex to keep the liquid moving and to remove the grit from suspension. The manufacturer's literature indicates that the unit consistently removes nearly 100% ! t tI I j of 65-mesh grit, 85% of 80-mesh grit and 65% of 100-mesh grit. The unit provides aeration to "freshen" the incoming sewage flow. The unit is 'sue manufactured of galvanized steel or stainless steel as Figure 5-12. Walker Rolling Grit Chamber required. An airlift grit from the unit and sends to a grit washer. The grit washer removes the g rice for the stainless washes, classifies and dewaters the material. The budget p steel unit is $65,000 for the equipment or $98,000 installed. t. Fluidyne Hvdro-Grit:, The Fluidyne system is a free-standing, high efficiency unit r 100 mesh s The unit removes at least 90 percent of solids ove manufactured of fiberglass reinforced polyester and is not subject to corrosion. One unit 8-feet in diameter is required. The unit is provided with a grit screw he classifier made of galvanized steel construction. r� material classifier is dropped into a dewatering and conveying system also. The gat container for disposal. The budget price for the unit is i$1 5 000in E for pure e equipment or $172,500 installed. The Hydro -Grit is illustratedP 13a and in section in Figure 5-13b. Okeechobee Utility u e 2004 thority Technical Memorandum No. 1 5 - 14 WWTP Expansion 11 A18"0 FLANGED 18"0 FLANGED INFLUENT — 5'-3" 4'-3" 0 3 HP REGEN BLOWERS ❑ ❑ ;EPARATOR NE )RO—GRIT FIGURE 5-13A HYDRO -GRIT PLAN METZGER & WILLARD, INC. Civil " Environmental Engineers Tampa, Florida 33637 (813) 977-6005 • 4"0 VENT LINE 18"0 AIR/LIQUID SEPARATOR EL. 12.50 E4 u EL 11.00 I----------- C EL- zsz -4 EL 7.375 / I 18"0 EFFLUENT —/ 18"0 INFLUENT II I q EL. 1.00 4"0 FLANGE EL 0.00 2" GROUT (BY OTHERS) r� (4) 5/8" HOLES PER LEG FOR 1/2" ANCHORS - BY OTHERS VI EW A -A 1 1/2"0 NPT AIR INLET (FROM 'PD' BLOWER) (4) SUPPORT LEGS FIGURE 5-13B HYDRO -GRIT ELEVATION • METZGER & WILLARD, INC. Civil • Environmental Engineers Tompa. Florida 33637 (813) 977-6005 0 Aeration TWO MGD ALTERNATIVE: The existing aeration basin consists of a two -channel US Filter/Envirex Orbal Oxidation Ditch Activated Sludge unit, with a design capacity of 1.0 MGD. It is anticipated that the Authority will continue with this process as developed in the previous expansion program. For the 2.0 MGD flow alternative, two alternatives have been evaluated for the aeration system as follows: 1. Install two new disc aerators in each of the two channels to increase the capacity of the existing tank (Two -Channel Option). 2. Construct a third channel to the existing unit, including two new disc aerators to increase the capacity of the system. For the two alternatives, the manufacturer of the Orbal process has recommended that the facility be operated at a sludge age no greater than 10 — 12 days in the warm water temperatures of South Florida. According to US Filter/Envirex when the sludge ages • increases, "endogenous respiration and oxidation of otherwise non -biodegradable species occurs, which results in excessively high oxygen uptake rates", which can "make it difficult to maintain adequate DO in the inner channel, and result in poor sludge settleability and high effluent turbidity". As a result, solids washout may be experienced during peak hydraulic flows during warm weather. The existing facility has experienced some algal growth on the aerators. Each alternative considers the installation of weatherhoods to prevent algal growth. 1. Two -Channel Option: This option requires the installation of two new 40 HP disk aerators in each channel (4 total) while upgrading the capacity of the unit to a maximum of 2.4 MGD. Two velocity baffles are also required to smooth the flow in the channel. The transfer ports between the channel, the center pier and the effluent transfer piping to the clarifiers have all been designed to accommodate an annual average flow of 2.0 MGD. Based upon the 2-channel configuration, the unit will not remove total phosphorus to I ess than 2 mg/L without chemical precipitation or some other type • Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 17 June 2004 • of biological phosphorus removal. The need for phosphorus removal is determined by the ultimate disposal of the efflue nt. The unit will operate under the following conditions: Biological Loading 30# CBOD/1000 CF of Volume MLSS 3400 mg/L Sludge Age 8 days Retention Time 13.5 hours Sludge Yield 0.87 South Florida facilities exhibit more stable operating characteristics when operated in this fashion, i.e., better sludge settleability and low effluent turbidity. For the above, equipment costs are budgeted as follows: Aerators 139,000 Weatherhoods 95,000 Installation 117,000 TOTAL 351,000 • If additional phosphorus removal is required to meet stringent effluent limitations, an additional reactor is required. A 45-foot by 45-foot by 14.5 foot SWD anaerobic unit with submersible mixer and recirculating pump would be required, and could eliminate the requirement for the chemical feed for phosphorus removal. The equipment cost for the anaerobic unit is $40,000, plus installation or $60,000 total. The Two -Channel Option is illustrated in Figure 5-14. 2. Three -Channel Option: This alternative would require the construction of a third channel on the existing Orbal unit with the installation of two new 30 HP aerators. The equipment cost for this option is as follow s: Aerators 85,000 Weatherhoods 85,000 Installation 85,000 • TOTAL 255,000 Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 18 June 2004 • (2) New 40 Hp AeraWm OpOonal Arombi c Tank FIGURE 5--14 TWO —CHANNEL AERATION BASIN MODIFICAMNS r METZGER &WILLARD, INC. Cirri! - Er: viron►n en tvi Engin eers Tampa, Florida 33637 ($13) $77—Spp.5 • 0 • In addition, the three -channel option would require the construction of the third channel, walkways, handrails and additional electrical costs, at approximately $423,000, including a 30 percent contingency. A detailed breakdown is provided in Appendix B . The unit would operate with an anoxic zone built in so that phosphorus removal is accomplished within the aeration basin. The unit would operate under the following conditions: Biological Loading 17# CBOD/1000 CF of Volume MLSS 2000 mg/L Sludge Age 9 days Retention Time 24.8 hours Sludge Yield 0.86 The Three -Channel Option is illustrated in Figure 5-15. THREE MGD ALTERNATIVE: For a proposed design flow of 3 MGD, the best possibl a scenario is as follows: 1. Install two new disc aerators in each of the existing two channels to increase the capacity of the existing tank. This modification is the same as the Two Channel Option provided in the 2.0 MGD Alternative analysis. 2. Construct a new two -channel unit to match the existing aeration basin. This new unit would be rated at 1.0 MGD with the possibility of installing two new disc aerators in the future to upgrade the facility to 2.0 MGD. 3. A flow splitter box is required to direct the flows in the appropriate quantities to the two aeration basi ns. The new aeration basin would be installed to the northeast of the existing unit. The new unit will operate under the following conditions: Biological Loading MLSS Sludge Age Retention Time Sludge Yield Technical Memorandum No. 1 WWTP Expansion 15# CBOD/1000 CF of Volume 2000 m g/L 8 days 30.0 hours 0.87 Okeechobee Utility Authority 5 - 20 June 2004 r (2) Now 30 HP Aerators f'IWKL 0-10 1 THREE —CHANNEL AERATION BASIN MODIFICATIONS INRTZGER & VALLARD,INC. Glvrr • En vironmen s`a� Engineers Tampa, Florida 33537 (813) 977—SCCS Clarification The existing clarifier mechanisms are US Filter/Envirex TOW-BRO Unitube Sludge Removers, with a capacity of 1.0 MGD AADF each. The existing clarifiers are shown in Figure 2-5. These are adequate for expansion to 2.0 MGD. For an annual average daily flow of 2.0 MGD, the following characteristics are anticipated for the two clarifiers: PER TOTAL CLARIFIER Annual Average Daily Flow 2.0 MGD 1.0 MGD Peak Hourly Flow 4.0 MGD 2.0 MGD 75% Flow (Class I Reliability) with One Unit out of Operation 1.5 MGD 1.5 MGD For an expansion to 3.0 MGD, a third clarifier is required, designed to match the existi ng units and with a capacity of 1.0 MGD. • Filtration The existing filters are traveling bridge filters. Two of the units were installed during the plant expansion of 1998. The first unit was installed with the reclaimed water system construction in 1991. The older unit is currently out of service and should either be completely rehabilitated or replaced. The Traveling Bridge Filters have required a large amount of maintenance over the years; however, their budget prices are fairly low compared to other filter systems available. If the Authority determines to remain with the Traveling Bridge Filters, the following options are presented. 1. US Filter Davis/Davco: The existing units are US Filter Davco units. This option includes providing one new unit in lieu of the repair of the existing older unit. A comparable Steel Gravisand XCell Traveling Bridge Filter with air scour and surface skimmer has a budget price of $120,000 per unit or $180,000 installed. 2. Parkson Smartfilter Travelinq Bridge Filter: This option includes providing a new unit in lieu of the repair of the existing older unit. The Parkson Smartfilter is Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 22 June 2004 • • • similar to the Davco unit, has a loading rate of 2.0 gpm/sf and a backwash rate of 25 gpm/sf. Two options are provided: 1. Provide the unit with steel walls (budget price of $145,250 for the unit, $217,875 installed). 2. Install the unit in a cast -in -place concrete tank (budget price of $125,000 for the unit, or $187,500 installed — excluding the concrete tank). Other filter options, which would replace the existing traveling bridge filters, include the following: 3. Infilco-Deciremont Automatic Backwash Filter: Two of these units are anticipated to be required to replace all of the existing traveling bridge filters. The system is designed to meet the requirements of Class I Reliability. The system is designed for 4.0 gpm/sf at peak flow and less than 2 gpm/sf at average annual flow. The backwash rate is 23 gpm/sf, with a backwash discharge of 192 gpm. Figure 5-16 illustrates the ABW Filter. The equipment budget price is $230,000 with an installed price of $345,000. 4. Sanitaire/ABJ Drum Filters: This option involves replacing all of the existing traveling bridge filters with three Drum Filters from Sanitaire. Each of the units is capable of 1112 gpm and provides Class I Reliability. The units are fully enclosed stainless steel structures or fiberglass reinforced polyester, as required. Figure 5-17 illustrates the Drum Filters. The equipment budget prices are as follows: 304 SS 316 SS* Equipment $240,000 $276,000 Installation 120,000 138,000 TOTAL $360,000 414,000 * Assumed 15% increase for 316 SS 5. US Filter/Krucier Hvdrotech Discfilter: The Discfilter provides filtration with a compact footprint. Two units sized for 2.0 MGD will replace the existing traveling bridge filters and will provide Class I Reliability if one unit is out of service. The units have a simple automated control system and afford easy maintenance. The units are available in 304 SS for an equipment budget cost of $360,000, or an installed budget cost of $540,000. For 316 SS, the units have a budget price Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 23 June 2004 0 • • ILA SLUDGE REMOVAL PIPING (BY OTHERS)) B EFFLUENT ?RAIN SUMP (OPT.) 24" X 24 X 4" DEEP (BY OTHERS) COMMON EFFLUENT CHANNEL WEIR WALL J WASTE CHANNEL WEIR 11-1 60 z N � MR WILL CawaN IWLUENT p AIM LEI.- -.5j. PLAN VIE wm WALL jAj ffSTION "A-A" TANK LENGTH V + 4--v 1'-0' ( 1'-0' 3_e INFLUENT PORTS SPACED AT 2'-0" D.C. M INLET OPTIONAL) TOP OF WEIR ADJUSTABLE EFFLUENT WEIR (TYP.)7 (BY OTHERS) SECTION "B-8" OVERALL LENGTH V + 22'-0' FILTER BED LENGTH V PER PROPOSAL MEDIA DEPTH ADJUSTABLE EFFLUENT WEIR (TYP.) (By OTHERS) arTION -(--C- FIGURE 5-16 ABW DRUM FILTER METZGER &WILLARD, INC. Civil - Environmentol Engineers T—p.. Fl orldo 33637 (813) 977-6005 0 0 0 12'0 OUTLET 90.00 7.13 1 17.50 70.00 ANCHOR HOLES ENTER TO CENTER 83.75 NOTES: 1) SCREEN PANELS NOT SHOWN FOR CLARITY, . DIMENSIONS ARE IN INCHES UNLESS OTHERWISE NOTED. PIPING WEIGHT ESTIMATED AT 40DO IDs. PRESSURE r- SPRAY BAR INLET THROTTLING VALVE 4's OUTLET FROM SOLDS TROUGH 1- 12'0 INLET nI 1H 1 J 104.00 108.5Q ANCHOR HOLES COM TO COMER DRUM DRIVE MOTOR N'r iURE VALVE SPRAY BAR H IP FIGURE 5-17 ABJ FILTER METZGER & WILLARD, INC. Civil • Environmental Engineers Tompa, Florida 33637 (813) 977-6005 I* of $414,000, with an installed budget price of $621,000. Figure 5-18 illustrates the Hydrotech Discfilter, Figure 5-18. Hydrotech Discfilter 6. Parkson Dvnasand Filter:, The Dynasand is a continuous -backwash, upflow, deep bed granular media filter. The units are continuously cleaned by recycling sand internally through an air lift pipe and sand washer. Clean sand re- distributes on top of the sand bed. The filter provides a continuous, uninterrupted flow of filtrate and reject water and requires no shut dow n for backwash. The unit has "no moving parts" and requires minimal maintenance. The units can be installed within a concrete basin or can be free-standing. Loading rates are 50 — 100 gpm/sf for wash water and 100 — 150 scfm/sf for the air required to clean the unit. The units themselves can be loaded 3 — 5 gpm/sf with an effluent of 20 — 150 ppm of Total Suspended Solids (TSS) and will provide a filtrate TSS of 5 — 10 ppm, based upon loading rates. The units have a budget price of $30,000 per module, with 12 modules required for the flow with Class I Reliability. Therefore, the total budget price is $280,000 for the equipment or $420,000 installed. Figure 5-19 illustrates the Dynasand Filter system. Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 26 June 2004 0 9 0 Figure 5-19. Dynasand Filter 7. Tetra Process Technologies Tetra Deep Bed Filters:, The Tetra Deep Bed Filter is a cast -in -place concrete system with three filtration units, a mudwell and a clearwell. The unit includes the hardware, the filter media, the backwash pumps, blowers, mudwell pumps, instrumentation and controls and has a budget price of $465,000 for the equipment or $697,500 installed. Figure 5-20 illustrates the system. For the 2 MGD alternative, additional filter capacity of 700,000 gpd is required to be added to the facility. For the 3 MGD alternative, additional filter capacity of 1.4 MGD is required to be added to the facility. These alternatives are discussed further in the next section of this report. Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 27 June 2004 45' PIPE GALLERY AREA FIF] BLOWERS BW PUMPS ❑ ❑ J J J J 1 2 3 0 � a � J U TYPICAL LAYOUT • FIGURE 5-20 TETRA DEEPBED FILTERS METZGER & WILLARD, INC. Civil • Environmentol Engineers Tompo, Florido 33637 (813) 977-6005 • • • Effluent PurnOnq, Chlorine Contact and Chlorination The Authority is currently changing the chlorination system to a sodium hypochlorite system and moving away from gaseous chlorine due to safety concerns. The new chlorine feed system being purchased is si zed to handle current and future flows. For the 2 MGD alternative, two options have been identified for the chlorine contact system. The first includes adding onto the existing multi -tank configuration, as shown in Figure 5-21. Two new tanks, 7,000 gallons each will be added to the system. A new tank will also be added to the effluent pump station. This option is the least expensive, with a budget price of $175,000. The second option includes replacing the existing multi -tank system with one cast -in - place concrete tank, as illustrated in Figures 5-22a and 5-22b. The chlorine contact chambers and effluent pump station are provided in one structure, with flow measurement. The effluent pump station can pump directly to the ponds for storage or to the reclaimed water user directly. For the 3 MGD alternative, two new 7,000 gallon trains (four tanks total) would be required. Based upon the effluent disposal strategy selected, the pump choices may be affected to provide adequate pumping capacity to reach the ultimate disposal site. Technical Memorandum No. 1 WWTP Expansion 5-29 Okeechobee Util ity Authority June 2004 0 Le L. Lea ci 10" CROSS REMOVE EXISTING PLUG 10 mm 10" CV 10 CROSS 1w GV Ov �/ 10' PLUG 10" CROSS JJJ 10" TEE (2) 10' GV -- - - - -- - - - - - - - 70" GV 10' CV 10` GV 10* GV GV GV 10" GV 1 n 1 1/2- TEE IF- - - - - - ii OPOSED 7 7,000 qw. CHLOFNNE 000 CONTACT,,, L-- O"ACT �.A.N H ORE TR C 0 1 NTI L CIO c RNA! BASIN A N 24' L- - --- - - - - - ---- - - - - - - - - - - - - - - - - -- - - - - - - - - - - - :!P C CHL N , �- ir,.=-. o �'S J!"E GL 7.."', �1' TK" 7, ON AC� ST' L& CONTRAC CONTACT BASIN T BASIN BASIN _N C ( rA ZIN BASIN FililJ LL— — — — — — — — — PUM Ill. P STA, P) TEE TEC P. (p .37.311 pm CHLORINEI SOLUTION PIPE r CONTROL BOX -'-�P--A. Icr OVER40W (DlP.) 1NV..X9 ALL 4' PIPE & VALVES T0--" BE REMOVED & REPLACED EXIST. W. TEE '0' GATE VALVE WTH 6, PIPE & VALVES L,iNORMALLY CLOSED L FIGURE 5-21 EXPANDED CHLORINE CONTACT CHAMBER TO D-InAL METZGER &WILLARD, INC Civil - Environmentol Engineers To-p.. FI orldo 33637 (813) 977-6005 • Ll f• omr— vine (m r— as m .) e-4• 1 £I (' Y uq [ vnauw vKVF w.unaw NHtl1I1 fix.) sr,ws flap wrz M.e) ,m q!. Nld1p- S fP SNp r.]' eE0. Px[IM[M iNIN� uwr a.xnu � I — — s II -I rw•m. '•rr neJ r'. b — II b rr v nrw J MANS. P4 aunt rnu I (RUIUK) I ,- .•-,Y � I b r— ,ate-�— — J .•-,cr ,. I w AN& — — I _ iI ,m w,x.ux ExNaa a .a cauwx I y — — — J e p EA� .Y xoTa %— — — — I 7ttAN5 Pi L ute�wc u va / I jiunm) Il —_f o0o y �J ha TO Em.wEN} p15POSK q l� —,r woia, aPEx�rzo eru vK.[ ,e•.n• m u• a 1, r (fx , [ 1 4) I[' ery (Tx.) Ir — -az eau vu e r-o• x r-a' I I r-a ,•_r I To fTd,..Q FIGURE 5-22A CAST IN PLACE CHLORINE CONTACT CHAMBER METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa. Florida 33637 (813) 977-6005 0 np rst Y rtul a YYKVF Kweew xw.ron sro• wa M.o rw.) %eo�,sl, rug/�M Mwl a ss.0 ea i I Ir sra wx Me rx.) I. se L`� —®Ilro_sxeall I I II II L_ JL _---_LJ-- LL------ r rr+ r verse rw aunc uuu a•a• cauux - _ e• EL suss L ,e• nwr pnucxr HV'0. ]eM FIGURE 5-22B CAST IN PLACE CHLORINE CONTACT CHAMBER SECTIONS METZGER Se WILLARD, INC. Civil • Environmental Engineers Tamp., Florida 33637 (813) 977-6005 • Detailed Opinion of Costs Appendix B provides a detailed opinion of the construction costs for each of the alternatives. TABLE 5-2. 2.0 MGD ALTERNATIVE — OPINION OF PROBABLE CONSTRUCTION COST PROCESS DETAIL I LOW END HIGH END 1. Headworks 506,500 824,500 2. Master Pump Station 475,000 475,000 3. Aeration Basin 501,000 655,000 4. Phosphorous Removal Tank 600,000 600,000 5. Clarification 0 0 6. Filtration 180,000 1,019,200 Low end is adding a new traveling bridge filter, high end is replacing all units with new cast -in - place concrete units with backwash system, mudwell, clearwell and air scour system 7. Chlorine Contact Chamber/Effluent Pump Station 110,000 609,300 Low end is adding new pre -cast tanks, and high end is constructing a new cast -in -place concrete basin with pump station 8. Administration/Laboratory Building 220,000 220,000 9. Site Work, 5% 129,600 220,200 10. Electrical, 15% 408,300 693,500 11. Yard Piping, 15% 469,600 797,500 12. Mobilization, 10% 360,000 611,400 SUBTOTAL 3,960,000 6,725,600 13. 1 Contingency, 30% 1,188,000 2,017,700 TOTAL — RANGE* 5,148,000 8,743,300 * Does not include modifications to existing Contact Stabilization WWTP (1985) • Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 33 June 2004 TABLE 5-3. 3.0 MGD ALTERNATIVE — OPINION OF PROBABLE CONSTRUCTION COST PROCESS DETAIL I LOW END HIGH END 1. Headworks 650,000 824,5001 2. Master Pump Station 475,000 475,000 1 3. Flow Splitter Box 100,000 100,000 4. Aeration Basin 1,653,100 1,653,100 5. Phosphorous Removal Tank 600,000 600,000 6. Clarification 1 450,000 450,000 7. Filtration 360,000 1,528,700 Low end is adding two new traveling bridge filters - high end is replacing all units with new cast -in - place concrete units with backwash system, mudwell, clearwell and air scour system 8. Chlorine Contact Chamber/Effluent Pump Station 150,000 914,000 Low end is adding new pre -cast tanks, and high end is constructing a new cast -in -place concrete basin with pump station 9. Administration/Laboratory Building 220,000 220,000 10. Site Work, 5% 232,900 338,300 11. Electrical, 15% 733,700 1,065,500 • 12. Yard Piping, 15% 843,700 1,225,400 13. Mobilization, 10% 646,800 939,500 SUBTOTAL 7,115,200 10,334,000 14. 1 Contingency, 30% 2,134,600 3,100,200 TOTAL — RANGE* 9,249,800 13,434,200 * Does not include modifications to existing Contact Stabilization WWTP (1985) The opinions of cost were developed with a 30 percent contingency and are based upon proposals received from the manufacturer's representatives for the equipment, where possible. Currently, a nationwide cement shortage is affecting cost and availability on concrete products. In addition, steel and fuel prices are affecting construction costs severely. 10 Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 5 - 34 June 2004 • • • With the 3.0 MGD alternative, the advantages include the ability to postpone further expansion work until approximately the year 2013, based upon Rule 62-600.450( 8). Preliminary planning and design would be required to start at that time. In addition, the facility is easily expanded to a 4.0 MGD facility as follows: TABLE 5-4. 4.0 MGD EXPANSION FROM 3.0 MGD — OPINION OF PROBABLE CONSTRUCTION COST PROCESS DETAIL I OPINION OF COST 1. Headworks I 0 2. Master Pump Station 80,000 Provide new pump and controls 3. Flow Splitter Box 0 4. Aeration Basin 550,000 1 5. Phosphorous Removal Tank 0 I I6. Clarification I 500,000 7. Filtration 0 8. Chlorine Contact Chamber/Effluent Pump Station 165,000 9. Administration/Laboratory Building 0 10. Site Work, 5% 64,800 11. Electrical, 15% 204,000 I 12. Yard Piping, 15% 234,600 I 13. Mobilization, 10% 179,800 SUBTOTAL 1,978,200 1 1 14. 1 Contingency, 30% 596,500 1 TOTAL — Expansion from 3.0 MGD to 4.0 MGD 2,574,700 Technical Memorandum No. 1 WWTP Expansion Okeechobee Utility Authority 5 - 35 June 2004 • • SECTION 6 POTENTIAL STRATEGIES FOR THE EXISTING CONTACT STABILIZATION FACILITY The existing Contact Stabilization Activated Sludge wastewater treatment facility is currently off-line and consists of the following treatment units: Surge Basin Contact Aeration Re -Aeration Clarifiers Digesters Chlorine Contact TOTAL 350,402 gallons 70,641 34,895 106,387 176,435 142,760 85,626 967,145 gallons or 129,300 cf Although it is unlikely that the facility will be used as a part of future expansion plans associated with the wastewater treatment plant, potential uses for the facility have been identified and are summarized herein. The structure is old and has begun to crack and corrode. The existing blowers have been off-line since 1998 and while they may be operative at this time, they were originally installed and have been in operation since 1985. These blowers are most likely at the end of their service life. The existing exposed air piping and diffusers require replacement. Alternatives for the facility that have been considered include the following: 1. Flow Equalization 2. Leachate Treatment 3. Septage Treatment Technical Memorandum No. 1 WWTP Expansion Okeechobee Utility Authority 6-1 June 2004 • Flow Equalization As a flow equalization facility, the Contact Stabilization facility could easily be modified to provide approximately 0.97 MGD of storage. The existing surge basin alone could likewise provide approximately approximately 0.35 MGD of storage. The unit is already piped for flow from the existing static screen headworks. Modifications to connect to the proposed headworks would be required. New return pumps and piping would be required. A breakdown of the antici pated costs is as follows: 1. Blowers 80,000 2. Air Piping 50,000 3. Piping 30,000 4. Pumps 20,000 5. Concrete Modifications 80,000 6. Electrical 50,000 SUBTOTAL 310,000 30% Contingency 93,000 TOTAL 403,000 However, the proposed Master Pump Station is acting as a flow equalization system since the pumps are connected to variable frequency drives (VFD). The VFDs provide the pumps the ability to operate at reduced speeds and act to shave off the flow peaks that could potentially overload the treatment works. The pumps would be active over a longer period of time pumping at the lower rate and would pick up speed as the flows to the plant increase. All flow to the plant is pumps, so instantaneous peaks tend to be attenuated. The Master Pump Station and the Headworks work to protect the aeration basin from hydraulic overloads. As a result, the Master Pump Station will perform flow equalization and the existing tankage at the Contact Stabilization facility could be employed in a more beneficial use. Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 6-2 June 2004 0 Leachate Treatment The existing tankage was evaluated for use in leachate treatment. Typically, leachate requires a detention time of 5 to 30 days, based upon the characteristics of the leachate. In addition, after aeration, the leachate requires a post -treatment system — a membrane filter or constructed wetland to complete the treatment. For a detention time of 5 days, the quantity of leachate that could be treated is as follows: 790,710 gallons of aeration capacity/5 days or 158,000 gpd of leachate. For a detention time of 30 days, the quantity of leachate that could be treated is as follows: 790,710 gallons of aeration capaci ty/30 days or 26,400 gpd of leachate. The quantity and quality of the leachate is necessary to properly size the system. Requested information was recently provided and shows a very high strength variable waste. . Leachate would require trucking in from the Okeechobee County landfill to the site for treatment. Solids would be returned to the landfill for disposal. Anticipated costs for the leachate treatment facility are as follows, and does not include trucking: 1. Dump Station 100,000 2. Rehabilitate Clarifiers 100,000 3. Blowers 75,000 4. Air Piping 30,000 5. Piping 25,000 6. Pumps 20,000 7. Concrete Modifications 50,000 8. Electrical 50,000 9. Membrane Filter System 100.000 SUBTOTAL 550,000 30% Contingency 165,000 TOTAL 715,000 The main disadvantage with leachate treatment are the unknowns associated with the quality of the leachate. The quantity on a daily and even weekly basis may be fairly small; however, the material may contain excessive amounts of metals, chemicals and Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 6-3 June 2004 • possibly toxic substances. Odors could also be a problem, depending upon the materials in the leachate. Another concern with leachate treatment is the potential that the leachate may affect the quality of the reuse water and may harm the citrus at the Williamson Cattle Company site. Sentacie Treatment The existing tankage at the Contact Stabilization facility could easily be modified to treat septage. A newly adopted Okeechobee County ordinance has limited property usage through severe setbacks for septage disposal; and, the Authority would be providing a much needed service to the community by accepting septage from residential haulers. From the EPA Handbook of Septage Treatment and Disposal, design values for septage are as follows: TS, mg/L 40,000 TVS, mg/L 25,000 TSS, mg/L 15,000 VSS, mg/L 10,000 BOD5, mg/L 7,000 COD, mg/L 15,000 TKN, mg/L 700 NH3-N, mg/L 150 Total P, mg/L 250 Alkalinity, mg/L 1,000 Grease, mg/L 8,000 pH 6.0 LAS, mg/L 150 Al, mg/L 50 As, mg/L 0.2 Cd, mg/L 0.7 Cr, mg/L 1.0 Cu, mg/L 8.0 Fe, mg/L 200 Hg, mg/L 0.25 Mn, mg/L 5 Ni, mg/L 1 Pb, mg/L 10 Se, mg/L 0.1 Zn, mg/L 40 Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 6-4 June 2004 • Retention time for appropriate septage treatment is recommended by the EPA document of 20 — 40 days for waste with a temperature greater than 64 deg F or 20 — 30 days for waste with a temperature greater than 68 deg F. For a 30 day detention time, the quantity of septage to be treated at the facility is as follows: 790,710 gallons of aeration capacity/30 days or 26,400 gpd of septage. Using the existing tankage, the following treatment strategy is proposed as shown in Figure 6-1. 1. Dump Station: Haulers would unload their trucks at the dump station and rinse out the remaining material from the trucks. The dump station would screen the material and pump to the aeration basin. Testing and monitoring would be performed to evaluate the received w astes. 2. Aeration: The existing surge basin, aeration tanks, and digesters are converted to the septage treatment facility. New blowers, air piping and diffusers are required. 3. Clarifiers: The existing clarifiers would be used to separate the solids and iliquids. The solids would be pumped to the aerobic digester/sludge processing system at the main wastewater treatment plant. The liquid portion would be returned to the front of the main plant for treatment. Odors from the facility may be a concern. The original surge basin could be covered to prevent problems and the collected air treated in a mulch bed, similar to the odor control systems provided at Authority vacuum pump stations. An opinion of the costs for this alternative is as follows: 1. Dump Station 2. Rehabilitate Clarifiers 3. Blowers 4. Air Piping 5. Piping 6. Pumps 7. Concrete Modifications 8. Electrical SUBTOTAL 30% Contingency TOTAL 0 Technical Memorandum No. 1 WWTP Expansion 100,000 100,000 80,000 50,000 30,000 20,000 80,000 50.000 510,000 153,000 663,000 Okeechobee Utility Authority 6-5 June 2004 • GESTER PUMP �r SOLIDS PUMP STA ION TO SLUDGE PROCESSIN k r� TION SUPERNATANT TO PLANT DRAIN PUMP STATION - TO MAIN WWTP FIGURE 6-1 SEPTAGE TREATMENT FACWTY METZGER & WILLARD, INC. Civil • Environmentol Engineers Tompo, Florida 33637 (813) 977-6005 • The main advantage of converting the Contact Stabilization facility to a septage treatment facility is the facility is able to meet a valuable need in the community that is in keeping with one of the missions of the Authority — to provide wastewater treatment and disposal. Existing septage haulers in the area have few options for disposal, since the setback ordinances have reduced the amount of land available for disposal. Direct landfill of untreated liquid septage is costly. As an alternative and if the available volume is adequate at the WWTP, septage could be directed into the headworks at the plant through a dump station. Based upon EPA Design Values, 250 gallons of septage is the equivalent of 20 — 25 houses connected through the regular collection system from an organic standpoint. The septage facility would be required to monitor the license status of haulers per County ordinance and maintain records of amounts and collection locations to prevent potentially harmful wastes from entering the system. The Authority will be able to re -coup some of the costs by applying a fee to the private • contractors that will be using the facilities. • Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 6-7 June 2004 • SECTION 7 RECOMMENDED PROGRAM FOR WWTP EXPANSION As a part of the development of this report, meetings were held with staff to review operations and capital cost concerns. As a result of these meetings, the following program for the expansion of the Wastewater T reatment Facility is recommended. 1. Expand the facility to 3.0 MGD to prevent two separate constru ction projects within the next 8 years. 2. Include the following units to provide a more efficient facility. A. Headworks — Bar S creen and Grit Collector — Units that cl can the screenings and grit are preferred over other units so that odors are greatly reduced and organics are returned to the aeration basin for treatment. B. Provide a Master Pump Station after the headworks to reduce "stress" on the in -town pump stations, as well as to act as flow equalization to reduce the potential of hydraulic surges thro ugh the facility. • C. Install a flow splitter box between the two aeration basins to divide the flows in accordance with the ratings of each basi n. D. Install aerators in the existing basin to increase its capacity. Construct a new two -channel unit adjacent to the existing unit. E. Construct a phosphorus removal tank to reduce phosphorus from the effluent, since the Lake Okeechobee Watershed has been identified as an area where phosphor us is of concern. F. Install one new clarifier. G. Install two new filters. H. Install two new chlorine contact "trains". I. Construct a new laboratory/administration buildi ng to allow for the Authority staff to continue to monitor and administer the operations of the facility. J. Construct a new residuals management facility, as discussed in Technical Memorandum No. 2. K. Construct the effluent disposal system, as discussed in Technical Memorandum No. 3. Figure 7-1 illustrates the proposed 3.0 MGD facility. In addition, the opinion of probable construction cost for the proposed program is shown in Table 7-1. 0 Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 7-1 June 2004 • LJ • TABLE 7-1. OPINION OF PROBABLE CONSTRUCTION COST FOR RECOMMENDED PROGRAM TO EXPAND THE WWTP TO 3.0 MGD —WITH FUTURE EXPANSION TO 4.0 MGD. PROCESS 3.0 MGD FUTURE 4.0 MGD 1. Headworks 708,375 - 2. Demolition of CSAS WWTP (1985) 100,000 - 3. Master Pump Station 475,000 80,000 4. Flow Splitter Box 100,000 - 5. Aeration Basin 1,653,100 550,000 6. Phosphorus Removal Tank 600,000 - 7. Clarification 450,000 500,000 8. Filtration 360,000 - 9. Chlorine Contact Chamber/Effluent Pump Station 150,000 165,000 10. Administration/Laboratory Building 220,000 - 11. Site Work, 5% 240,800 64,800 12. Electrical, 15% 758,600 204,000 13. Yard Piping, 15% 872,400 234,600 14. Mobilization, 10% 668,800 179,800 SUBTOTAL 7,357,100 1,978,100 15. Contingency, 30% 2.207.100 593,400 TOTAL Technical Memorandum No. 1 Okeechobee Utility Authority WWTP Expansion 7-3 June 2004 • IPROPOSED MASTER PROPOSED FLOW METER ASSEMBLY J PUMP STATION GENERATOR AND FUEL TANK EXISTING LINED HOLDING POND EXISTING LINED 1 HOLDING '. HOLDING POND AERATION AERATORS FLOW SPUTTER BOX _J 171 ;WAS/RAS PUMP STATION LEGEND: E30SYING PROPOSED TO BE DEMOLISHED FIGURE 7-1 POTENTIAL SITE PLAN METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, Florida 33637 (813) 977-6005 • • CN • WASTEWATER SYSTEM CALCULATIONS DESIGN FLOW CHARACTERISTICS WWTP PDF Peak Daily Flow MGD 4.00 MMF Maximum Monthly Flow MGD 3.00 AADF Annual Average Daily Flow MGD 2.00 MF Minimum Flow MGD 0.80 PHF Peak Hourly Flow MGD 4.00 INFLUENT AND EFFLUENT CHARACTERISTICS INF EFF CBOD5 mg/L 300 < 10 TSS mg/L 250 < 10 TN mg/L 40 < 3 TP mq/L 10 < 1 Site & Wastewater Characteristics Domestic WW Elevation at Site Influent BOD Influent CBOD Li Influent TSS Influent VSS Influent NH3-N Ni Influent TKN Influent P Average Daily Flow Q Peak to Average Ratio Peak Daily Flow Qpeak Average to Min Ratio Minimum Flow Minimum Wastewater Temp Temp Minimum Air Temp pH Range Hexane Solubles Effluent CBOD Le Effluent TSS Effluent VSS Effluent NH3-N Effluent P DESIGN 36.00 ft 275.00 mg/I 300.00 mg/I 250.00 mg/I 175.00 mg/I 40.00 mg/I 50.00 mg/I 10.00 mg/I 2,000,000.00 gpd 2.00 4,000,000.00 gpd 2.50 800,000.00 gpd 20.00 deg C 0.00 deg C 6-8.5 75.00 mg/I < 10 5.00 mg/I max < 10 5.00 mg/I max 5.00 mg/I max < 1 15.00 mg/I max < 2 6.00 mg/I max • OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 1 of 10 2.0 MGD 0 0 0 Aeration Basin F/Mv Design Criteria 0.05 - 0.10 # BOD/day/# MLVSS 0.10 #/BOD/DAY/# MLVSS 0.05 <= F/Mv <= 0.1; therefore, OK per 10 State Standards MLSS Design Criteria 3000 - 5000 mg/I MLSS 3,400.00 mg/I 3000 <= MLSS <= 5000, therefore, OK per 10 State Standards MLVSS (65%)(MLSS) 2,210.00 mg/I BOD loading F Total BOD applied to the activated sludge process = 8.34(Q)(Li)/10116 5,004.00 # BOD/day Micro-organism Mass in Aerator My Total Aerator MLVSS = F / (F/Mv) 50,040.00 # MLVSS Volume of Oxidation Ditch Required Volume, from Orbal design manual, 30# BOD/1000 cf 166,800.00 cf REQ Inner Channel Width 20.00 ft Middle Channel Width 20.00 ft Length of Straight Section 69.00 ft Center Island Radius 5.00 ft Channel Wall Thickness 1.17 ft Water Depth 14.00 ft Overall Length 163.68 ft Overall Width 94.68 ft Percent Inner Channel Volume 65,029.38 cf 38.87% Middle Channel Volume 102,273.59 cf 61.13% Total Unit Volume Sufficient volume is provided (167, 303 cf vs. 166,800 cf - OK) 167,302.97 cf 1,251,426.22 gal X-Section Area Velocities Inner channel cross section area & flow velocities 280.00 sf 0.12 fps Middle channel cross section area & flow velocities 280.00 sf 0 12 fps (Note: Ability to recycle designed in for nitrification/denitrification if surface water discharge is provided in the future) Total Aerator Mixed Liquor Loadings MLSS (MLSS mg/1) (0.0624 # -1/mg / mg - 1000 co (Volume cf) 35,495.00 # MLSS Design Volumetric Loading = Design Organic Loading / Aeration Volume Design Volumetric Loading < 30; therefore OK per ORBAL Design Stds 29.91 # Inf BOD/day 1,000 cf Aeration OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 2 of 10 2.0 MGD t Unit Retention Time w/o recycle flow = Total Unit Volume / Q Oxygen Requirements # BOD Total BOD applied to the activated sludge process = 8.34 (Q) (Li) / 1016 # NH3 - N Total NH3-N applied to the activated sludge process = 8.34 (Q) (Ni) / 10^6 Initial Base Oxygen Requirements for BOD = I 1.04 # 02/ # BOD for NH3-N = 4.60 # 02/ # NH3-N # 02 applied X Initial Base Oxygen Requirements for BOD for NH3-N Denitrification Recovery 50% of # 02/day for NH3 - N Total Base 02 Required = AOR = (# 02/day BOD) + (# 02/day NH3-N) - (# 02/day Denitrification Recovery) Channel DO levels Inner Channel Middle Channel 2 ppm 2 ppm DO Correction Factor = a' [b' Csw - Co / Cs ] 1.024A ( T - 20 ) a' relative air/water interface diffusion rate for mechanical aerators b' the ratio of saturation values of wastewater to clean water at wastewater temperature and actual atmospheric pressure Csw saturation of clean water at surface Cs oxygen saturation concentration for clean water under standard conditions T wastewater temperature Co desired DO Inner Channel Middle Channel 02 required per channel = SOR = Total Base 02 Required * Channel % Volume / DO Correction Factor • @ PDF @ AADF 7.51 hrs 15 02 hrs 5,004.00 # BOD/day 667.20 # NH3 - N/day 5,204.16 # 02/day 216.84 # 02/hour 3,069.12 # 02/day 127.88 # 02/hour 1,534.56 # 02/day 63.94 # 02/hour 6,738.72 # 02/day 280.78 # 02/hour 0.95 0.98 9.06 mg/I 9.07 mg/I 20.00 deg C 2.00 mg/I 0.74 0.74 OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 3 of 10 2.0 MGD • • 0 Inner 3,550.21 #/day Middle 5,583.52 #/day TOTAL 9,133.74 #/day 380.57 #/hr With Oxygen Reserve of 25% at maximum disc immersion TOTAL Oxygen Required 475.72 #/hr Standard 02/disc (Aeration Design condition) 1.42 #/hr @ 43 rpm Total Number of Discs = Total 02 required / Std 02/Disc 335.01 Disks Use 288.00 Disks Disc Distribution based upon %age of Aeration Required per Channel Total number of Disks X Percentage Aeration Inner Channel 112.00 disks Middle Channel 176.00 disks Aerator Shafts per Channel Inner I 61 Middle 6 Number of Disks per Shaft = Number of disks per channel / Shafts per Channel Inner 19.00 discs Middle 29.00 discs Minimum spacing > 5", Per Orbal Design Standards OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 4 of 10 2.0 MGD 0 CLARIFIERS Note: Clarifiers are sized for 1.0 MGD each Minimum Side Water Depth 10' @ MLSS = 2,000 mg/l + I'per additional 1,000 mg/I MLSS Therefore, at 4,000 mg/I of MLSS, Clarifier depths are 10 + 1 + 1 12.00 ft Assumed Depth 12.00 ft Assumed Diameter 80.00 ft Assumed Area (2 units) A/2 5026.56 sf each A 10,053.12 sf total Clarifier Design Flow Qpeak 4,000,000.00 gpd Class I Reliability requires 75% total design flow capacity with largest unit out of service; therefore, 75% Clarifier Design Flow 3,000,000.00 gpd AADF 2,000,000.00 gpd Surface (Hydraulic) Loading Rate (SurfLR) Normal Operations Qpeak / A 397.89 gpd/sf Class I Operations 0.75 Qpeak / A/2 596.83 gpd/sf SurfLR <= 1,000, therefore, OK, per 10 State Standards Solids Loading Rate @ 100% Return (100% AADF) (SoILR) Normal Operations (MLSS) (Qpeak + 100% Return)(8.34) / (A)(10^6) 19.91 # solids/day/sf Class I Operations (MLSS) (0.75Qpeak + 100% Return)(8.34) / (A/2)(10^6) 33.18 # solids/day/sf SoILR <= 35; therefore, OK per 10 State Standards Clarifier Weir Diameter 78.00 ft Length (Pi)(Diameter) 245.04 If each clarifier Weir Overflow Rate (Qpeak/2) (LF of Weir) 8,161.77 gpd/If weir/clarifier Weir overflow rate <= 20, 000; therefore, OK per 10 State Standards Sludge Recycle Ratio R 100.00 % Recycle AADF Solids Concentration of Settled Sludge 0.80 % Solids Recycle Flow R X Q 1,000,000.00 gpd per clarifier t Aeration Unit Retention Time with Recycle Flow = Total Unit Volume / Q + 2(Recycle Flow) at PDF 5.01 hours at AADF 7.51 hours Sludge Recycle Ratio to Maintain 1.00 % Solids 67.00 % Recycle Recycle Flow R X Q 670,000.00 gpd per Clarifier t Aeration Unit Retention time with Recycle flow = Total Unit Volume / Q + 2(Recycle Flow) at PDF 5.62 hours at AADF 8.99 hours OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 5 of 10 2.0 MGD • • 9 FILTERS Three Davco ABW Traveling Bridge Filters Maximum Allowable Filtration Rate (10 State Standards) Surface Area Manufacturer's Rated AADF Capacity Manufacturer's Rated Surface Loading Rate = Capacity / Surface Area 11440 min/day FLOW CHARACTERISTICS PDF Peak Daily Flow MGD MMF Maximum Monthly Flow MGD AADF Annual Average Daily Flow MGD MF Minimum Flow MGD PHF Peak Hourly Flow MGD PDF is attenuated through plant Design Flow Rate - Peak Class I Reliability Flow Rate 75% Peak Flow Rate Determine Filtration Rate for 1, 2 and 3 Filters in operation 1 Filter Q at Qpeak Qpeak / SA 4.00 at Qclassl Qclassl / SA 3.00 at Qaadf Qaadf / SA 2.00 RATE IS TOO HIGH 2 Filters at Qpeak Qpeak / SA 4.00 at Qclassl Qclassl / SA 3.00 at Qaadf Qaadf / SA 2.00 RATE IS TOO HIGH FOR MAXIMUM FLOW RATE 3 Filters at Qpeak Qpeak / SA 4.00 at Qclassl Qclassl / SA 3.00 at Qaadf Qaadf / SA 2.00 THREE FILTERS ARE REQUIRED FOR 2.0 MGD DESIGN OD WWTP 4.00 3.00 2.00 0.80 4.00 5.00 gpm/sf 242.00 sf 700,000.00 gpd 2.00 gpm/sf 4.00 MGD 3.00 MGD SA 242.00 NG 11.48 gpm/sf 242.00 NG 8.61 gpm/sf 242.00 NG 5.74 gpm/sf 484.00 NG 5.74 gpm/sf 484.00 OK 4.30 gpm/sf 484.00 OK 2.87 gpm/sf 726.00 OK 3.83 gpm/sf 726.00 OK 2.87 gpm/sf 726.00 OK 1.91 gpm/sf <5 <5 <2 OLIA Permit Renewal 7/16/2004 WWTP System Calculations Page 6 of 10 2.0 MGD 4 Filters at Qpeak Qpeak / SA 4.00 968.00 OK 2.87 gpm/sf < 5 at Qclassl Qclassl / SA 3.00 968.00 OK 2.15 gpm/sf < 5 at Qaadf Qaadf / SA 2.00 968.00 OK 1.43 gpm/sf < 2 RATE IS SUFFICIENT FOR 2.0 MGD. OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 7 of 10 2.0 MGD i i • CHLORINE CONTACT BASIN AND SYSTEM FLOW CHARACTERISTICS PDF Peak Daily Flow MGD MMF Maximum Monthly Flow MGD AADF Annual Average Daily Flow MGD MF Minimum Flow MGD PHF Peak Hourly Flow MGD DESIGN OD WWTP 4.00 3.00 2.00 0.80 4.00 PDF is attenuated through plant Minimum Contact Time per 10 State Standards 15.00 minutes Class I Reliability 50% total design flow with largest unit out of service Sketch of System T1 c c o 4260 U gal U I 1 4260 gal 1 To Ponds 1 T2 T3 T4 7000 I 7000 gal gal 7000 7000 gal gal .,.>. ... :. Effluent Transfer Pump Station wN-notch Weir and Flowmeter New Units OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 8 of 10 2.0 MGD • Three Trains (As is) Vol = 8520 + 14000 + 14000 Contact Time at AADF = Total Volume / AADF Contact Time at PDF = Total Volume / PDF Class I Reliability Contact Time Provided = Total Volume - 14,000 al / 50%PDF .... ` , •hF�4w6?':vn.' ��','',��r„-: °�.`,.,�. �i;,.c �-,�, ,gb;� i•''.yu }, ¢ f `4 %^�" '"' :<L.>!"S Vol = 8520 + 14000 + 14000 + 14000 Contact Time at AADF = Total Volume / AADF Contact Time at PDF = Total Volume / PDF Class I Reliability Contact Time Provided = Total Volume - 14,000 qal / 50%PDF Operational Considerations for Hiah Level Disinfection Per FDEP 62-600.440(5)(c) I Pre -Disinfected Effluent Fecal Coliform Levels: Fecal Coliform <= 1,000 / 100 mL Chlorine Residual X Contact Time >= 25 Therefore: 25 / Contact time = Desired Residual 1,000 / 100 mL <= Fecal Coliform <= 10,000 / 100 mL Chlorine Residual X Contact Time >= 40 Therefore: 40 / Contact time = Desired Residual 10,000 / 100 mL <= Fecal Coliform Chlorine Residual X Contact Time >= 120 Therefore: 120 / Contact time = Desired Residual Per FDEP 62-600.440(5)(e) at Flowrate PDF AADF PDF AADF PDF AADF 36,520.00 gallons total = 26.29 minutes 13.15 minutes 16.21 minutes 50,520.00 gallons total 36.37 minutes = 18.19 minutes = 26.29 minutes Residual Required TSS <= 5 mg/L prior to disinfection. Addition of Chlorine at the filters is acceptable to aid in TSS control. Proposed dosage of Chlorine for disinfection, pre -filter algae control and pre-treatment odor control Chlorine Use per Day 20 ppm X PDF X 8.34 #/gal 1.9 1.0 3.0 1.5 9.1 4.6 mg/L mg/L mg/L mg/L mg/L mg/L 20.00 mg/L 667.00 #/day OK NG No OK OK NI OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 9 of 10 2.0 MGD 0 0 0 OPERATING PROTOCOL: Normal ODeratina Conditions: Chlorine feed rate is adjusted, based upon the pre -chlorination fecal coliform reading, to provide an adequate chlorine residual. The OUA facility sees a fecal coliform reading of less than 1000/100 mL of sample, therefore the feed rate is adjusted to provide the following residuals: at AADF 1.0 mg/L at PDF 1.9 ma/L Abnormal Ooeratina Conditions: For an abnormal operating condition of the Chlorine Contact Basins (i.e., one unit is out of service for repairs/maintenance, the chlorine feed rate may require adjustment. To meet Class I Reliability requirements of the Largest Unit out of service and the remaining units handling 50% of the PDF, the chlorine feed rate should be adjusted to provide a minimum residual of the following: at 50% PFD 1.1 mg/L. Determine flow rates for various trains emoved from service for repair and maintenance: Volume,being rMin Flowrate, ins Flow Condition gal Residual CT, min Flowrate, gpm MGD Comments only at AADF 8,520 1.0 25 340.8 0.491 When AADF or PDF reaches these rates, at PDF 1.9 13.158 647.5 0.932 a second train shall be on line. + T2 (or T3) at AADF 22,520 1.0 25 900.8 1 297 When AADF or PDF reaches these rate at PDF 1.9 13.158 1,711.5 2.465 s, a third train shall be on line. T2 only at AADF 14,000 1.0 25 560.0 0.806 When AADF or PDF reaches these rates, at PDF 1.9 13.158 1,064.0 1.532 T3 shall be on line. T2 + T3 at AADF 28,000 1.0 25 1,120.0 1.613 When AADF or PDF reaches these rates, at PDF 1.9 13.158 2,128.0 3.064 T1 shall be added - all three trains on line. T1 + T2 + T3 at AADF 36,520 1.0 25 1,460.8 2.104 When AADF or PDF reaches these rates, at PDF 1.9 13.158 2,775.5 3.997 a fourth train shall be constructed. T1 + T2 + T3 + T4 at AADF 50,520 1.0 25 2,020.8 2.910 When AADF or PDF reaches these rates, at PDF 1.9 13.158 3,839.5 5.529 a fifth train shall be constructed. OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 10 of 10 2.0 MGD r-1 0 • • • WASTEWATER SYSTEM CALCULATIONS DESIGN FLOW CHARACTERISTICS WWTP PDF Peak Daily Flow MGD 6.00 MMF Maximum Monthly Flow MGD 4.50 AADF Annual Average Daily Flow MGD 3.00 MF Minimum Flow MGD 1.20 PHF Peak Hourly Flow MGD 6.00 INFLUENT AND EFFLUENT CHARACTERISTICS INF EFF CBOD5 mg/L 300 < 10 TSS mg/L 250 < 10 TN mg/L 40 < 3 TP mg/L 10 < 1 Site & Wastewater Characteristics DESIGN Domestic WW Elevation at Site 36.00 ft Influent BOD 275.00 mg/I Influent CBOD Li 300.00 mg/I Influent TSS 250.00 mg/I Influent VSS 175.00 mg/I Influent NH3-N Ni 40.00 mg/I Influent TKN 50.00 mg/I Influent P 10.00 mg/I Average Daily Flow Q 3,000,000.00 gpd Peak to Average Ratio 2.00 Peak Daily Flow Qpeak 6,000,000.00 gpd Average to Min Ratio 2.50 Minimum Flow Qmin 1,200,000.00 gpd Minimum Wastewater Temp Temp 20.00 deg C Minimum Air Temp 0.00 deg C pH Range 6 - 8.5 Hexane Solubles 75.00 mg/I Effluent CBOD Le < 10 5.00 mg/I max Effluent TSS < 10 5.00 mg/I max Effluent VSS 5.00 mg/I max Effluent NH3-N < 1 15.00 mg/I max Effluent P < 2 6.00 mg/1 max OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 1 of 14 3.0 MGD C� Aeration Basin 1 1 2.0 MGD F/Mv Design Criteria 0.05 - 0.10 # BOD/day/# MLVSS 0.05 <= F/Mv <= 0.1; therefore, OK per 10 State Standards MLSS Design Criteria 3000 - 5000 mg/I MLSS 3000 <= MLSS <= 5000; therefore, OK per 10 State Standards MLVSS (65%)(MLSS) Q = 2,000,000 gpd Qpeak = 4,000,000 gpd Qmin = 800,000 gpd BOD loading F Total BOD applied to the activated sludge process = 8.34(Q)(Li)/10116 Micro-organism Mass in Aerator My Total Aerator MLVSS = F / (F/Mv) Volume of Oxidation Ditch Required Volume, from Orbal design manual, 30# BOD/1000 cf Inner Channel Width Middle Channel Width Length of Straight Section Center Island Radius Channel Wall Thickness Water Depth Overall Length Overall Width Inner Channel Volume Middle Channel Volume Total Unit Volume Sufficient volume is provided (167, 303 cf vs. 166,800 cf - OK) 0.10 #/BOD/DAY/# MLVSS 3,400.00 mg/I 2,210.00 mg/I 5,004.00 # BOD/day 50,040.00 # MLVSS 166,800.00 cf REQ 20.00 ft 20.00 ft 69.00 ft 5.00 ft 1.17 ft 14.00 ft 163.68 ft 94.68 ft Percent 65,029.38 cf 38.87% 102,273.59 cf 61.13% 167,302.97 cf 1,251,426.22 gal X-Section Area Velocities Inner channel cross section area & flow velocities 280.00 sf 0.12 fps Middle channel cross section area & flow velocities 280.00 sf 0.12 fps (Note: Ability to recycle designed in for n itrificatio n/d en itrifi cation if surface water discharge is provided in the future) Total Aerator Mixed Liquor Loadings MLSS (MLSS mg/1) (0.0624 # -1/mg / mg - 1000 cf) (Volume cf) 35,495.00 # MLSS Design Volumetric Loading = Design Organic Loading / Aeration Volume Design Volumetric Loading < 30; therefore OK per ORBAL Design Stds t Unit Retention Time w/o recycle flow = Total Unit Volume / Q PDF 7.51 hrs 29.91 # Inf BOD/day 1,000 cf Aeration @ AADF 15.02 hrs OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 2 of 14 3.0 MGD 0 • Oxygen Requirements # BOD Total BOD applied to the activated sludge process = 8.34 (Q) (Li) / 10^6 #NH3 - N Total NH3-N applied to the activated sludge process = 8.34 (Q) (Ni) / 10^6 Initial Base Oxygen Requirements for BOD = 1.04 # 02/ # BOD for NH3-N = 4.60 # 02/ # NH3-N # 02 applied X Initial Base Oxygen Requirements for BOD for NH3-N Denitrification Recovery 60% of # 02/day for NH3 - N Total Base 02 Required = AOR = (# 02/day BOD) + (# 02/day NH3-N) - (# 02/day Denitrification Recovery) Channel DO levels Inner Channel 2 ppm Middle Channel (Outer Channel) 0 ppm DO Correction Factor = a' [(b' Csw - Co) / Cs ] 1.024A (T - 20 ) a' relative air/water interface diffusion rate for mechanical aerators b' the ratio of saturation values of wastewater to clean water at wastewater temperature and actual atmospheric pressure Csw saturation of clean water at surface Cs oxygen saturation concentration for clean water under standard conditions T wastewater temperature Co desired DO Inner Channel Do correction Middle Channel Do correction OUA Permit Renewal WWTP System Calculations Page 3 of 14 5,004.00 # BOD/day 667.20 # NH3 - N/day 5,204.16 # 02/day 216.84 # 02/hour 3,069.12 # 02/day 127.88 # 02/hour 1,841.47 # 02/day 76.73 # 02/hour 6,431.81 # 02/day 267.99 # 02/hour 0.95 0.98 9.06 mg/I 9.07 mg/I 20.00 deg C 2.00 mg/I 0.72 = 0.93 �J 7/ 16/2004 3.0 MGD • • 0 Inner Channel Outer Channel (Middle Channel) Volume Split, % 38.87 61.13 Process Split, % 43.50 56.50 AOR, Ib/hr = (AOR)(Process Split Percentage) 116.58 151.42 SOR, Ib/hr = (AOR for Channel) / Do correction for Channel 161.80 162.82 No. of Shafts/Basin 6 6 No. of Discs/Shaft _ (SOR for channel) / (1.42 Ib/hr per disc) / (6 shafts/basin) 19 19 No. of Discs/Basin 114 114 Design Disc RPM 43 43 Design Disc Immersion, Inches 17.50 17.50 Design SOR/Disc, lb/hr 1.42 1.42 Maximum Disc RPM 55 55 Maximum Disc Immersion, Inches 21 21 Maximum SOR/Disc, lb/hr 2.50 2.50 Largest Drive Out of Design Maximum Output Service No. of Discs in Service Basin 228 228 209 Std Oxygen Provided/Basin, Ib/hr 324 570 523 Reserve Over Design, % 1 76 61 Std Oxygen Delivery Required w/no denitrification 479 and 2 mg/L DO in all channels, Ib/hr OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 4 of 14 3.0 MGD Aeration Basin 2 1 1.0 MGD (UPGRADABLE TO 2.0 MGD) F/Mv Design Criteria 0.05 - 0.10 # BOD/day/# MLVSS 0.05 <= F/Mv <= 0.1; therefore, OK per 10 State Standards MLSS Design Criteria (Per ORBAL Design Stds) MLVSS (65%)(MLSS) Q = 1,000,000 gpd Qpeak = 2,000,000 gpd Qmin = 400,000 gpd BOD loading F Total BOD applied to the activated sludge process = 8.34(Q)(Li)/10^6 Micro-organism Mass in Aerator My Total Aerator MLVSS = F / (F/Mv) Volume of Oxidation Ditch Required Volume, from Orbal design manual, 15# BOD/1000 cf Inner Channel Width Middle Channel Width Length of Straight Section Center Island Radius Channel Wall Thickness Water Depth Overall Length Overall Width Inner Channel Volume Middle Channel Volume Total Unit Volume Sufficient volume is provided (167, 303 cf vs. 166,800 cf - OK) i 0.10 #/BOD/DAY/# MLVSS 2,000.00 mg/I 1,300.00 mg/I 2,502.00 # BOD/day 25,020.00 # MLVSS 166,800.00 cf REQ 20.00 ft 20.00 ft 69.00 ft 5.00 ft 1.17 ft 14.00 ft 163.68 ft 94.68 ft Percent 65,029.38 cf 38.87% 102,273.59 cf 61.13% 167,302.97 cf 1,251,426.22 gal X-Section Area Velocities Inner channel cross section area & flow velocities 280.00 sf 0.06 fps Middle channel cross section area & flow velocities 280.00 sf 0.06 fps (Note: Ability to recycle designed in for nitrification/denitrification if surface water discharge is provided in the future) Total Aerator Mixed Liquor Loadings MLSS (MLSS mg/1) (0.0624 # -1/mg / mg - 1000 cf) (Volume cf) 20,879.41 # MLSS Design Volumetric Loading = Design Organic Loading / Aeration Volume Design Volumetric Loading < 30; therefore OK per ORBAL Design Stds t Unit Retention Time w/o recycle flow = Total Unit Volume / Q 0 PDF 15.02 hrs OUA Permit Renewal WWTP System Calculations Page 5 of 14 14.95 # Inf BOD/day 1,000 cf Aeration @ AADF 30.03 hrs 7/16/2004 3.0 MGD 0 0 0 Oxygen Requirements # BOD Total BOD applied to the activated sludge process = 8.34 (Q) (Li) / 10^6 # NH3 - N Total NH3-N applied to the activated sludge process = 8.34 (Q) (Ni) / 1016 Initial Base Oxygen Requirements for BOD = I 1.04 # 02/ # BOD for NH3-N = 4.60 # 021 # NH3-N 1 # 02 applied X Initial Base Oxygen Requirements for BOD for NH3-N Denitrification Recovery 50% of # 02/day for NH3 - N Total Base 02 Required = AOR = (# 02/day BOD) + (# 02/day NH3-N) - (# 02/day Denitrification Recovery) Channel DO levels Inner Channel Middle Channel 2 ppm 2 ppm DO Correction Factor = a' [(b' Csw - Cc) / Cs ] 1.024A (T - 20 ) a' relative air/water interface diffusion rate for mechanical aerators b' the ratio of saturation values of wastewater to clean water at wastewater temperature and actual atmospheric pressure Csw saturation of clean water at surface Cs oxygen saturation concentration for clean water under standard conditions T wastewater temperature Co desired DO Inner Channel Middle Channel 2,502.00 # BOD/day 333 60 # NH3 - N/day 2,602.08 # 02/day 108.42 # 02/hour 1,534.56 # 02/day 63.94 # 02/hour 767.28 # 02/day 31.97 # 02/hour 3,369.36 # 02/day 140.39 # 02/hour 0.95 0.98 9.06 mg/1 9.07 mg/I 20.00 deg C 2.00 mg/1 0.72 0.72 OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 6 of 14 3.0 MGD 0 • 0 Inner Channel Outer Channel (Middle Channel) Volume Split, % 38.87 61.13 Process Split, % 43.50 56.50 AOR, Ib/hr = (AOR)(Process Split Percentage) 61.07 79.32 SOR, Ib/hr - (AOR for Channel) / Do correction for Channel 84.76 110.09 No. of Shafts/Basin 4 4 No. of Discs/Shaft _ (SOR for channel) / (1.42 Ib/hr per disc) / (4 shafts/basin) 15 19 No. of Discs/Basin 60 76 Design Disc RPM 43 43 Design Disc Immersion, Inches 17.50 17.50 Design SOR/Disc, Ib/hr 1.42 1.42 Maximum Disc RPM 55 55 Maximum Disc Immersion, Inches 21 21 Maximum SOR/Disc, Ib/hr 2.50 2.50 Design Maximum Output Largest Drive Out of No. of Discs in Service in Basin 136 136 117 Std Oxygen Provided/Basin, Ib/hr 193 340 293 Reserve Over Design, % 1 76 52 Std Oxygen Delivery Required w/no denitrification 195 and 2 mg/L DO in all channels, lb/hr OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 7 of 14 3.0 MGD CLARIFIERS Note: Clarifiers are sized for 1.0 MGD each Minimum Side Water Depth 10' @ MLSS = 2,000 mg/I + 1' per additional 1,000 mg/I MLSS Therefore, at 3400 mg/I of MLSS, Clarifier depths are 10 + 1 + 1 Assumed Depth Assumed Diameter Assumed Area (3 units) JA/3 = 5026.56 sf each Clarifier Design Flow Class I Reliability requires 75% total design flow capacity with largest unit out of service; therefore, 75% Clarifier Design Flow AADF Surface (Hydraulic) Loading Rate (SurfLR) Normal Operations Qpeak / A Class I Operations 0.75 Qpeak / A/2 SurfLR <= 1,000, therefore, OK, per 10 State Standards A Qpeak Qclassl Q Solids Loading Rate @ 100% Return (100% AADF) (SoILR) Normal Operations (MLSS) (Qpeak + 100% Return)(8.34) / (A)(10^6) Class I Operations (MLSS) (0.75Qoeak + 100% Return)(8.34) / (A/3)(10^6) 2 SoILR <= 35, therefore, OK per 10 State Standards Clarifier Weir Diameter Length (Pi)(Diameter) Weir Overflow Rate (Qpeak/3) (LF of Weir) Weir overflow rate <= 20, 000; therefore, OK per 10 State Standards Sludge Recycle Ratio R Solids Concentration of Settled Sludge Recycle Flow R X Q t Aeration Unit Retention Time with Recycle Flow = Total Unit Volume / Q + 3(Recycle Flow) at PDF at AADF Sludge Recycle Ratio to Maintain Recycle Flow RXQ Aeration Unit Retention time with Recycle flow = Total Unit Volume / Q + 3(Recycle Flow) at PDF at AADF 12.00 ft 12.00 ft 80.00 ft 15,079.68 sf total 6,000,000.00 gpd 4,500,000.00 gpd 3,000,000.00 gpd 397.89 gpd/sf 895.24 gpd/sf 16.92 # solids/day/sf 21.15 # solids/day/sf 78.00 ft 245.04 If each clarifier 8,161.77 gpd/If weir/clarifier 100.00 % Recycle AADF 0.80 % Solids 1,000,000.00 gpd per clarifier 3.34 hours 5.01 hours 1.00 % Solids 67.00 % Recycle 670,000.00 gpd per Clarifier 7.50 hours 11.99 hours OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 8 of 14 3.0 MGD 0 FILTERS Three Davco ABW Traveling Bridge Filters Maximum Allowable Filtration Rate (10 State Standards) 5.00 gpm/sf Surface Area 242.00 sf Manufacturer's Rated AADF Capacity 700,000.00 gpd Manufacturer's Rated Surface Loading Rate = Capacity / Surface Area 11440 min/day 2.00 gpm/sf DESIGN FLOW CHARACTERISTICS OD WWTP PDF Peak Daily Flow MGD 6.00 MMF Maximum Monthly Flow MGD 4.50 AADF Annual Average Daily Flow MGD 3.00 MF Minimum Flow MGD 1.20 PHF Peak Hourly Flow MGD 6.00 PDF is attenuated through plant Design Flow Rate - Peak 6.00 MGD Class I Reliability Flow Rate 75% Peak Flow Rate 4.50 MGD Determine Filtration Rate for 1, 2 and 3 Filters in operation 1 Filter Q SA at Qpeak Qpeak / SA 6.00 242.00 NG 17.22 gpm/sf at Qclassl Qclassl / SA 4.50 242.00 NG 12.91 gpm/sf at Qaadf Qaadf / SA 3.00 242.00 NG 8.61 gpm/sf RATE IS TOO HIGH 2 Filters at Qpeak Qpeak / SA 6.00 484.00 NG 8.61 gpm/sf at Qclassl Qclassl / SA 4.50 484.00 OK 6.46 gpm/sf at Qaadf Qaadf / SA 3.00 484.00 OK 4.30 gpm/sf RATE IS TOO HIGH FOR MAXIMUM FLOW RATE 3 Filters at Qpeak Qpeak / SA 6.00 726.00 NG 5.74 gpm/sf at Qclassl Qclassl / SA 4.50 726.00 OK 4.30 gpm/sf at Qaadf Qaadf / SA 3.00 726.00 OK 2.87 gpm/sf RATE IS TOO HIGH FOR PEAK RATE OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 9 of 14 3.0 MGD • • 4 Filters at Qpeak Qpeak / SA 6.00 968.00 OK 4.30 gpm/sf at Qclassl Qclassl / SA 4.50 968.00 OK 3.23 gpm/sf at Qaadf Qaadf / SA 3.00 968.00 NG 2.15 gpm/sf RATE IS TOO HIGH FOR AADF 5 Filters at Qpeak Qpeak / SA 6.00 1210.00 OK 3.44 gpm/sf < 5 at Qclassl Qclassl / SA 4.50 1210.00 OK 2.58 gpm/sf < 5 at Qaadf Qaadf / SA 3.00 1210.00 OK 1.72 gpm/sf < 2 RATE IS SUFFICIENT FOR 3.0 MGD. 6 Filters at Qpeak Qpeak / SA 6.00 1452.00 OK 2.87 gpm/sf < 5 at Qclassl Qclassl / SA 4.50 1452.00 OK 2.15 gpm/sf < 5 at Qaadf Qaadf / SA 3.00 1452.00 OK 1.43 gpm/sf < 2 RATE IS SUFFICIENT FOR 3.0 MGD. OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 10 of 14 3.0 MGD CHLORINE CONTACT BASIN AND SYSTEM FLOW CHARACTERISTICS PDF Peak Daily Flow MGD MMF Maximum Monthly Flow MGD AADF Annual Average Daily Flow MGD MF Minimum Flow MGD PHF Peak Hourly Flow MGD DESIGN OD WWTP 6.00 4.50 3.00 1.20 6.00 PDF is attenuated through plant Minimum Contact Time per 10 State Standards 15.00 minutes Class I Reliability 50% total design flow with largest unit out of service Sketch of System T1 T2 11 1 c c o 4260 I 7000 U gal gal U- I 1 11 4260 7000 gal gal 1 I11+ To Ponds T3 T4 T5 1 1 1 7000 gal 1 1 � 7000- T0:.0t} gal . _..�., Effluent Transfer Pump Station wN-notch Weir and Flowmeter New Units OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 11 of 14 3.0 MGD • mum Vol = 8520 + 14000 + 14000 = 36,520.00 gallons total Contact Time at AADF = Total Volume / AADF = 17.53 minutes OK Contact Time at PDF = Tntai Vnh imp PDF = I 8.76 minutes NG Class I Reliability Contact Time Provided = Total Volume 14,000 qal / 50%PDF = J �. OWN '�. 1��,;�.�_ 'nwi.*2 � � m, rnf.... . Vol = 8520 + 14000 + 14000 + 14000 = Contact Time at AADF = Total Volume / AADF = Contact Time at PDF = Total Volume / PDF = Class I Reliability Contact Time Provided = Total Volume - 14.000 qal / 50%PDF = Vol= 8520 + 14000 + 14000 + 28000 = Contact Time at AADF = Total Volume / AADF = Contact Time at PDF = Total Volume / PDF = Class I Reliability Contact Time Provided = Total Volume - 14.000 gal / 50%PDF = Operational Considerations for High Level Disinfection Per FDEP 62-600.440(5)(c) I Pre -Disinfected Effluent Fecal Coliform Levels: Fecal Coliform <= 1,000 / 100 mL Chlorine Residual X Contact Time >= 25 Therefore: 25 / Contact time = Desired Residual 1,000 / 100 mL <= Fecal Coliform <= 10,000 / 100 mL Chlorine Residual X Contact Time >= 40 Therefore: 40 / Contact time = Desired Residual 10,000 / 100 mL <= Fecal Coliform Chlorine Residual X Contact Time >= 120 Therefore: 120 / Contact time = Desired Residual at Flowrate PDF 50%PDF AADF PDF AADF PDF AADF 10.81 minutes 50,520.00 gallons total 24.25 minutes 12.12 minutes 17.53 minutes 64,520.00 gallons total 30.97 minutes 15.48 minutes 24.25 minutes Residual Required 1.6 1.0 0.8 MINIMUM 1.0 mg/L 2.6 1.3 7.7 3.9 mg/L mg/L mg/L mg/L mg/L mg/L mg/L NG OK NG C�]:1 OK OK OK OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 12 of 14 3.0 MGD Per FDEP 62-600.440(5)(e) TSS <= 5 mg/L prior to disinfection. Addition of Chlorine at the filters is acceptable to aid in TSS control. Proposed dosage of Chlorine for disinfection, pre -filter algae control and pre-treatment odor control 20.00 mg/L Chlorine Use per Day = 20 ppm X PDF X 8.34 #/gal = 1,001.00 #/day OPERATING PROTOCOL: Normal ODeratina Conditions: Chlorine feed rate is adjusted, based upon the pre -chlorination fecal coliform reading, to provide an adequate chlorine residual. The OUA facility sees a fecal coliform reading of less than 1000/100 mL of sample, therefore the feed rate is adjusted to provide the following residuals: at AADF 1.0 mg/L at PDF 1.6 mg/L Abnormal ODeratina Conditions: For an abnormal operating condition of the Chlorine Contact Basins (i.e., one unit is out of service for repairs/maintenance, the chlorine feed rate may require adjustment. To meet Class I Reliability requirements of the Largest Unit out of service and the remaining units handling 50% of the PDF, the chlorine feed rate should be adjusted to provide a minimum residual of the following: at 50% PFD 1 mg/L. OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 13 of 14 3.0 MGD Determine flow rates for various trains beina removed from service for reoair and maintenance: Volume, Min Flowrate, Trains Flow Condition gal Residual CT, min Flowrate, gpm MGD Comments T1 only at AADF 8,520 1.0 25 340.8 0.49 When AADF or PDF reaches these rates, at PDF 1.6 15.625 545.3 0.79 a second train shall be on line. T1 + T2 (or T3) at AADF 22,520 1.0 25 900.8 1.30 When AADF or PDF reaches these rates, at PDF 1.6 15.625 1,441.3 2.08 a third train shall be on line. T2 only at AADF 14,000 1.0 25 560.0 0.81 When AADF or PDF reaches these rates, at PDF 1.6 15.625 896.0 1.29 T3 shall be on line. T2 + T3 at AADF 28,000 1.0 25 1,120.0 1.61 When AADF or PDF reaches these rates, at PDF 1.6 15.625 1,792.0 2.58 T1 shall be added - all three trains on line. T1 + T2 + T3 at AADF 36,520 1.0 25 1,460.8 2.10 When AADF or PDF reaches these rates, at PDF 1.6 15.625 2,337.3 3.37 a fourth train shall be constructed T1 + T2 + T3 + T4 at AADF 50,520 1.0 25 2,020.8 2.91 When AADF or PDF reaches these rates, at PDF 1.6 15.625 3,233.3 4.66 a fifth train shall be constructed. T1 + T2 + T3 + T4 at AADF 64,520 1.0 25 2,580.8 3.72 When AADF or PDF reaches these rates, + T5 at PDF 1.6 15.625 4,129.3 5.95 a sixth train shall be constructed. OK up to 3.0 MGD AADF and 6.0 MGD PDF OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 14 of 14 3.0 MGD • • • WASTEWATER SYSTEM CALCULATIONS DESIGN FLOW CHARACTERISTICS WWTP PDF Peak Daily Flow MGD 8.00 MMF Maximum Monthly Flow MGD 6.00 AADF Annual Average Daily Flow MGD 4.00 MF Minimum Flow MGD 1.60 PHF Peak Hourly Flow MGD 8.00 INFLUENT AND EFFLUENT CHARACTERISTICS INF EFF CBOD5 mg/L 300 < 10 TSS mg/L 250 < 10 TN mg/L 40 < 3 TP mg/L 10 < 1 Site & Wastewater Characteristics DESIGN Domestic WW Elevation at Site 36.00 ft Influent BOD 275.00 mg/I Influent CBOD Li 300.00 mg/I Influent TSS 250.00 mg/I Influent VSS 175.00 mg/I Influent NH3-N Ni 40.00 mg/I Influent TKN 50.00 mg/I Influent P 10.00 mg/I Average Daily Flow Q 4,000,000.00 gpd Peak to Average Ratio 2.00 Peak Daily Flow Qpeak 8,000,000.00 gpd Average to Min Ratio 2.50 Minimum Flow Qmin 1,600,000.00 gpd Minimum Wastewater Temp Temp 20.00 deg C Minimum Air Temp 0.00 deg C pH Range 6 - 8.5 Hexane Solubles 75.00 mg/I Effluent CBOD Le < 10 5.00 mg/I max Effluent TSS < 10 5.00 mg/1 max Effluent VSS 5.00 mg/I max Effluent NH3-N < 1 15.00 mg/I max Effluent P < 2 6.00 mg/I max OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 1 of 14 4.0 MGD Aeration Basin 1 1 2.0 MGD F/Mv Design Criteria 0.05 - 0.10 # BOD/day/# MLVSS 0.05 <= F/Mv <= 0.1; therefore, OK per 10 State Standards MLSS Design Criteria 3000 - 5000 mg/I MLSS 3000 <= MLSS <= 5000; therefore, OK per 10 State Standards MLVSS (65%)(MLSS) Q = 2,000,000 gpd Qpeak = 4,000,000 gpd Qmin = 800,000 gpd BOD loading F Total BOD applied to the activated sludge process = 8.34(Q)(Li)/1016 Micro-organism Mass in Aerator My Total Aerator MLVSS = F / (F/Mv) Volume of Oxidation Ditch Required Volume, from Orbal design manual, 30# BOD/1000 cf Inner Channel Width Middle Channel Width Length of Straight Section Center Island Radius Channel Wall Thickness Water Depth Overall Length Overall Width Inner Channel Volume Middle Channel Volume Total Unit Volume Sufficient volume is provided (167, 303 cf vs. 166,800 cf - OK) • 0.10 #/BOD/DAY/# MLVSS 3,400.00 mg/I 2,210.00 mg/I 5,004.00 # BOD/day 50,040.00 # MLVSS 166,800.00 cf REQ 20.00 ft 20.00 ft 69.00 ft 5.00 ft 1.17 ft 14.00 ft 163.68 ft 94.68 ft Percent 65,029.38 cf 38.87% 102,273.59 cf 61.13% 167,302.97 cf 1,251,426.22 gal X-Section Area Velocities Inner channel cross section area & flow velocities 280.00 sf 0.12 fps Middle channel cross section area & flow velocities 280.00 sf 0.12 fps (Note: Ability to recycle designed in for nitrification/denitrification if surface water discharge is provided in the future) Total Aerator Mixed Liquor Loadings MLSS (MLSS mg/1) (0.0624 # -1/mg / mg - 1000 cf) (Volume cf) 35,495.00 # MLSS Design Volumetric Loading = Design Organic Loading / Aeration Volume Design Volumetric Loading < 30; therefore OK per ORBAL Design Stds t Unit Retention Time w/o recycle flow = Total Unit Volume / Q @ PDF 7.51 hrs 29.91 # Inf BOD/day 1,000 cf Aeration (p, AADF 15.02 hrs OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 2 of 14 4 0 MGD Oxygen Requirements # BOD Total BOD applied to the activated sludge process = 8.34 (Q) (Li) / 1016 # NH3 - N Total NH3-N applied to the activated sludge process = 8.34 (Q) (Ni) / 1016 Initial Base Oxygen Requirements for BOD = I 1.04 # 02/ # BOD for NH3-N = 4.60 # 02/ # NH3-N # 02 applied X Initial Base Oxygen Requirements for BOD for NH3-N Denitrification Recovery 60% of # 02/day for NH3 - N Total Base 02 Required = AOR = (# 02/day BOD) + (# 02/day NH3-N) - (# 02/day Denitrification Recovery) Channel DO levels Inner Channel 2 ppm Middle Channel (Outer Channel) 0 ppm DO Correction Factor = a' [(b' Csw - Cc) / Cs ] 1.024A (T - 20 ) a' relative air/water interface diffusion rate for mechanical aerators b' the ratio of saturation values of wastewater to clean water at wastewater temperature and actual atmospheric pressure Csw saturation of clean water at surface Cs oxygen saturation concentration for clean water under standard conditions T wastewater temperature Co desired DO Inner Channel Do correction Middle Channel Do correction OUA Permit Renewal WWTP System Calculations Page 3 of 14 5,004.00 # BOD/day 667.20 # NH3 - N/day 5,204.16 # 02/day 216.84 # 02/hour 3,069.12 # 02/day 127.88 # 02/hour 1,841.47 # 02/day 76.73 # 02/hour 6,431.81 # 02/day 267.99 # 02/hour 0.95 0.98 9.06 mg/I 9.07 mg/I 20.00 deg C As above mg/I 0.72 0.93 • 7/16/2004 4.0 MGD • • • Inner Channel Outer Channel (Middle Channel). Volume Split, % 38.87 61.13 Process Split, % 43.50 56.50 AOR, Ib/hr = (AOR)(Process Split Percentage) 116.58 151.42 SOR, Ib/hr = (AOR for Channel) / Do correction for Channel 161.80 162.82 No. of Shafts/Basin 6 6 No. of Discs/Shaft _ (SOR for channel) / (1.42 Ib/hr per disc) / (6 shafts/basin) 19 19 No. of Discs/Basin 114 114 Design Disc RPM 43 43 Design Disc Immersion, Inches 17.50 17.50 Design SOR/Disc, Ib/hr 1.42 1.42 Maximum Disc RPM 55 55 Maximum Disc Immersion, Inches 21 21 Maximum SOR/Disc, lb/hr 2.50 2.50 Largest Drive Out of Design Maximum Output Service No. of Discs in Service Basin 228 228 209 Std Oxygen Provided/Basin, Ib/hr 324 570 523 Reserve Over Design, % 1 76 61 Std Oxygen Delivery Required w/no denitrification 479 and 2 mg/L DO in all channels, Ib/hr OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 4 of 14 4.0 MGD Aeration Basin 2 1 2.0 MGD F/Mv Design Criteria 0.05 - 0.10 # BOD/day/# MLVSS 0 05 <= F/Mv <= 0.1; therefore, OK per 10 State Standards MLSS Design Criteria (Per ORBAL Design Stds) MLVSS (65%)(MLSS) Q = 2,000,000 gpd Qpeak = 4,000,000 gpd Qmin = 800,000 gpd BOD loading F Total BOD applied to the activated sludge process = 8.34(Q)(Li)/10^6 Micro-organism Mass in Aerator My Total Aerator MLVSS = F / (F/Mv) Volume of Oxidation Ditch Required Volume, from Orbal design manual, 30# BOD/1000 cf Inner Channel Width Middle Channel Width Length of Straight Section Center Island Radius Channel Wall Thickness Water Depth Overall Length Overall Width Inner Channel Volume Middle Channel Volume Total Unit Volume Sufficient volume is provided (167, 303 cf vs. 166,800 cf - OK) 0.10 #/BOD/DAY/# MLVSS 3,400.00 mg/I 2,210.00 mg/I 5,004.00 # BOD/day 50,040.00 # MLVSS ,166,800.00 cf REQ 20.00 ft 20.00 ft 69.00 ft 5.00 ft 1.17 ft 14.00 ft 163.68 ft 94.68 ft Percent 65,029.38 cf 38.87% 102,273.59 cf 61.13% 167,302.97 cf 1,251,426.22 gal X-Section Area Velocities Inner channel cross section area & flow velocities 280.00 sf 0.06 fps Middle channel cross section area & flow velocities 280.00 sf 0.06 fps (Note: Ability to recycle designed in for nitrification/denitrification if surface water discharge is provided in the future) Total Aerator Mixed Liquor Loadings MLSS (MLSS mg/1) (0.0624 # -1/mg / mg -1000 cf) (Volume cf) 35,495.00 # MLSS Design Volumetric Loading = Design Organic Loading / Aeration Volume Design Volumetric Loading < 30; therefore OK per ORBAL Design Stds t Unit Retention Time w/o recycle flow = Total Unit Volume / Q PDF 7.51 hrs OUA Permit Renewal WWTP System Calculations Page 5 of 14 29.91 # Inf BOD/day 1,000 cf Aeration AADF 15.02 hrs 7/ 16/2004 4.0 MGD • Oxygen Requirements # BOD Total BOD applied to the activated sludge process = 8.34 (Q) (Li) / 1016 # NH3 - N Total NH3-N applied to the activated sludge process = 8.34 (Q) (Ni) / 1016 Initial Base Oxygen Requirements for BOD = I 1.04 # 02/ # BOD for NH3-N = 4.60 # 02/ # NH3-N # 02 applied X Initial Base Oxygen Requirements for BOD for NH3-N Denitrification Recovery 60% of # 02/day for NH3 - N Total Base 02 Required = AOR = (# 02/day BOD) + (# 02/day NH3-N) - (# 02/day Denitrification Recovery) Channel DO levels Inner Channel Middle Channel 2 ppm 0 ppm DO Correction Factor = a' [(b' Csw - Co) / Cs ] 1.0241 (T - 20 ) a' relative air/water interface diffusion rate for mechanical aerators V the ratio of saturation values of wastewater to clean water at wastewater temperature and actual atmospheric pressure Csw saturation of clean water at surface Cs oxygen saturation concentration for clean water under standard conditions T wastewater temperature Co desired DO Inner Channel Middle Channel 5,004.00 # BOD/day 667.20 # NH3 - N/day 5,204.16 # 02/day 216.84 # 02/hour 3,069.12 # 02/day 127.88 # 02/hour 1,841.47 # 02/day 76.73 # 02/hour 6,431.81 # 02/day 267.99 # 02/hour 0.95 0.98 9.06 mg/I 9.07 mg/I 20.00 deg C As above mg/I 0.72 0.93 OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 6 of 14 4.0 MGD • Inner Channel Outer Channel (Middle Channel) Volume Split, % 38.87 61.13 Process Split, % 43.50 56.50 AOR, Ib/hr = (AOR)(Process Split Percentage) 116.58 151.42 SOR, Ib/hr = (AOR for Channel) / Do correction for Channel 161.80 162.82 No. of Shafts/Basin 6 6 No. of Discs/Shaft _ (SOR for channel) / (1.42 Ib/hr per disc) / (6 shafts/basin) 19 19 No. of Discs/Basin 114 114 Design Disc RPM 43 43 Design Disc Immersion, Inches 17.50 17.50 Design SOR/Disc, Ib/hr 1.42 1.42 Maximum Disc RPM 55 55 Maximum Disc Immersion, Inches 21 21 Maximum SOR/Disc, Ib/hr 2.50 2.50 Design Maximum Output Largest Drive Out of No. of Discs in Service in Basin 228 228 209 Std Oxygen Provided/Basin, Ib/hr 324 570 523 Reserve Over Design, % 1 76 61 Std Oxygen Delivery Required w/no denitrification 479 and 2 mg/L DO in all channels, Ib/hr OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 7 of 14 4.0 MGD • CLARIFIERS Note: Clarifiers are sized for 1.0 MGD each Minimum Side Water Depth 10' @ MLSS = 2,000 mg/I + 1' per additional 1,000 mg/I MLSS Therefore, at 3400 mg/I of MLSS, Clarifier depths are 10 + 1 + 1 Assumed Depth Assumed Diameter Assumed Area (4 units) JA/4 = 5026.56 sf each Clarifier Design Flow Class I Reliability requires 75% total design flow capacity with largest unit out of service; therefore, 75% Clarifier Design Flow AADF Surface (Hydraulic) Loading Rate (SurfLR) Normal Operations Qpeak / A Class I Operations 0.75 Qpeak / (A - A/4) SurfLR <= 1,000, therefore, OK, per 10 State Standards A Qpeak Qclassl Q Solids Loading Rate @ 100% Return (100% AADF) (SoILR) Normal Operations (MLSS) (Qpeak + 100% Return)(8.34) / (A)(10^6) Class I Operations (MLSS) (0.75QDeak + 100% Return)(8.34) / (A/4)(1016) 2 SoILR <= 35, therefore, OK per 10 State Standards Clarifier Weir Diameter Length (Pi)(Diameter) Weir Overflow Rate (Qpeak/4) (LF of Weir) Weir overflow rate <= 20, 000; therefore, OK per 10 State Standards Sludge Recycle Ratio R Solids Concentration of Settled Sludge Recycle Flow R X Q t Aeration Unit Retention Time with Recycle Flow = Total Unit Volume / Q + 4(Recycle Flow) at PDF at AADF Sludge Recycle Ratio to Maintain Recycle Flow R X Q t Aeration Unit Retention time with Recycle flow = Total Unit Volume / Q + 4(Recycle Flow) at PDF at AADF 12.00 ft 12.00 ft 80.00 ft 20,106.24 sf total 8,000,000.00 gpd 6,000,000.00 gpd 4,000,000.00 gpd 397.89 gpd/sf 397.89 gpd/sf 16.92 # solids/day/sf 28.21 # solids/day/sf 78.00 ft 245.04 If each clarifier 8,161.77 gpd/If weir/clarifier 100.00 % Recycle AADF 0.80 % Solids 1,000,000.00 gpd per clarifier 2.50 hours 3.75 hours 1.00 % Solids 67.00 % Recycle 670,000.00 gpd per Clarifier 5.62 hours 8.99 hours OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 8 of 14 4.0 MGD • i • FILTERS Six Davco ABW Traveling Bridge Filters Maximum Allowable Filtration Rate (10 State Standards) Surface Area Manufacturer's Rated AADF Capacity Manufacturer's Rated Surface Loading Rate = Capacity / Surface Area 11440 min/day FLOW CHARACTERISTICS PDF Peak Daily Flow MGD MMF Maximum Monthly Flow MGD AADF Annual Average Daily Flow MGD MF Minimum Flow MGD PHF Peak Hourly Flow MGD PDF is attenuated through plant Design Flow Rate - Peak Class I Reliability Flow Rate 75% Peak Flow Rate Determine Filtration Rate for 1, 2 and 3 Filters in operation 1 Filter Q at Qpeak Qpeak / SA 8.00 at Qclassl Qclassl / SA 6.00 at Qaadf Qaadf / SA 4.00 RATE IS TOO HIGH 2 Filters at Qpeak Qpeak / SA 8.00 at Qclassl Qclassl / SA 6.00 at Qaadf Qaadf / SA 4.00 RATE IS TOO HIGH FOR MAXIMUM FLOW RATE 3 Filters SA 242.00 242.00 242.00 484.00 484.00 484.00 at Qpeak Qpeak / SA 8.00 726.00 at Qclassl Qclassl / SA 6.00 726.00 at Qaadf Qaadf / SA 4.00 726.00 RATE IS TOO HIGH FOR PEAK RATE AND CLASS I RELIABILITY DESIGN OD WWTP 8.00 6.00 4.00 1.60 8.00 NG NG NG NG NG NG NG NG OK 5.00 gpm/sf 242.00 sf 700,000.00 gpd 2.00 gpm/sf at aadf 8.00 MGD 6.00 MGD 22.96 gpm/sf 17.22 gpm/sf 11.48 gpm/sf 11.48 gpm/sf 8.61 gpm/sf 5.74 gpm/sf 7.65 gpm/sf 5.74 gpm/sf 3.83 gpm/sf OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 9 of 14 4.0 MGD 0 • 10 4 Filters at Qpeak Qpeak / SA 8.00 968.00 NG 5.74 gpm/sf at Qclassl Qclassl / SA 6.00 968.00 OK 4.30 gpm/sf at Qaadf Qaadf / SA 4.00 968.00 OK 2.87 gpm/sf RATE IS TOO HIGH FOR PEAK RATE 5 Filters at Qpeak Qpeak / SA 8.00 1210.00 OK 4.59 gpm/sf at Qclassl Qclassl / SA 6.00 1210.00 OK 3.44 gpm/sf at Qaadf Q aadf / SA 4.00 1210.00 OK 2.30 gpm/sf RATE IS SLIGHTLY TOO HIGH FOR AADF 6 Filters at Qpeak Qpeak / SA 8.00 1452.00 OK 3.83 gpm/sf <5 at Qclassl Qclassl / SA 6.00 1452.00 OK 2.87 gpm/sf <5 at Qaadf Q aadf / SA 4.00 1452.00 OK 1.91 gpm/sf <2 RATE IS SUFFICIENT FOR ALL FLOW CONDITIONS. OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 10 of 14 4.0 MGD 0 • CHLORINE CONTACT BASIN AND SYSTEM DESIGN FLOW CHARACTERISTICS OD WWTP PDF Peak Daily Flow MGD 8.00 MMF Maximum Monthly Flow MGD 6.00 AADF Annual Average Daily Flow MGD 4.00 MF Minimum Flow MGD 1.60 PHF Peak Hourly Flow MGD 8.00 PDF is attenuated through plant Minimum Contact Time per 10 State Standards 15.00 minutes Class I Reliability 50% total design flow with largest unit out of service Sketch of System T1 T2 T3 T4 T5 T6 T7 a� a� c c 0 4260 7000 7000 7000 7000JQp . .".s 70a0 gal gal gal I I gal gala}'p 9 U LL 1 1 1 1 1 J 4260 7000 7000 7000 7000 700? 7000 gal gal gal gal gal : qaf°. ` " gal Effluent Transfer Pump Station 1%4, wN-notch Weir and Flowmeter 1 To Ponds OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 11 of 14 4 0 MGD -:`P'Y'ed,:�..^y�-Y+k.•4f%`s9ii:. a'II'B.Aat`Jd �..:x�,?� &,• «, .m .. Y_yu wttvc"x, *rv� ,s ,.. ,. v Vole- �$8520 + 14000 + 14000 = gallons totalMy 520.00 , 36 Contact Time at AADF = Total Volume / AADF = 13.15 minutes NG Contact Time at PDF = Total Volume / PDF = 6.57 minutes NG Class I Reliability Contact Time Provided = Total Volume - 14,000 �qal / 50%PDF = 8 11 minutes NG Vol = 8520 + 14000 + 14000 + 14000 = 50,520.00 gallons total Contact Time at AADF = Total Volume / AADF = 18.19 minutes OK Contact Time at PDF = Total Volume / PDF = 9.09 minutes NG Class I Reliability Contact Time Provided = Total Volume 14,000 gal / 50%PDF 13.15 minutes NG i'•: �;°tsa'c a" x, x9"a",,.s„`r .i. .': •n,,,'., Am.s,. i' ti .4.45•yx,..3;iiaF3v'Ns.�tl ...±<,"�T ' .<!J n P ,..,f ,µ'"•FpnYt'A�n,.' ,. .. a>,k+ssKj-..: ., ,. Vol = 8520 + 14000 + 14000 + 28000 = 64,520.00 gallons total Contact Time at AADF = Total Volume / AADF = 23.23 minutes OK Contact Time at PDF = Total Volume / PDF = 11.61 minutes NG Class I Reliability Contact Time Provided = Total Volume - 14,000 aal / 50%PDF = 18.19 minutes OK - Max ON Vol 8520 + 14000 + 42000 + 14000 78,520.00 gallons total Contact Time at AADF = Total Volume / AADF = 28.27 minutes OK Contact Time at PDF = Total Volume / PDF = 14.13 minutes NG Class I Reliability Contact Time Provided = Total Volume - 14,000 gal / 50%PDF = 23.23 minutes OK Vol — 8520 + 14000 56000 + 14000 = 92,520.00 gallons total Contact Time at AADF = Total Volume / AADF = 33.31 minutes OK Contact Time at PDF = Total Volume / PDF = 16.65 minutes OK Class I Reliability Contact Time Provided = Total Volume - 14,000 qal / 50%PDF = 28.27 minutes OK OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 12 of 14 4.0 MGD • Operational Considerations for Hiah Level Disinfection Per FDEP 62-600.440(5)(c) Pre -Disinfected Effluent Fecal Coliform Levels: Fecal Coliform <= 1,000 / 100 mL Chlorine Residual X Contact Time >= 25 Therefore: 25 / Contact time = Desired Residual 1,000 / 100 mL <= Fecal Coliform <= 10,000 / 100 mL Chlorine Residual X Contact Time >= 40 Therefore: 40 / Contact time = Desired Residual 10,000 / 100 mL <= Fecal Coliform Chlorine Residual X Contact Time >= 120 Therefore: 120 / Contact time = Desired Residual Per FDEP 62-600.440(5)(e) • at Flowrate I Residual Required PDF 1.5 mg/L 50%PDF 0.9 mg/L AADF 0.8 mg/L MINIMUM 1 0 mg/L PDF 2.4 mg/L AADF 1.2 mg/L PDF 7.2 mg/L AADF 3.6 mg/L TSS <= 5 mg/L prior to disinfection. Addition of Chlorine at the filters is acceptable to aid in TSS control. Proposed dosage of Chlorine for disinfection, pre -filter algae control and pre-treatment odor control 20.00 mg/L Chlorine Use per Day = 20 ppm X PDF X 8.34 #/gal = 1,334.00 #/day OPERATING PROTOCOL: Normal ODeratina Conditions: Chlorine feed rate is adjusted, based upon the pre -chlorination fecal coliform reading, to provide an adequate chlorine residual. The OUA facility sees a fecal coliform reading of less than 1000/100 mL of sample, therefore the feed rate is adjusted to provide the following residuals: at AADF 1.0 mg/L at PDF 1.5 mg/L Abnormal ODeratina Conditions: For an abnormal operating condition of the Chlorine Contact Basins (i.e., one unit is out of service for repairs/maintenance, the chlorine feed rate may require adjustment. To meet Class I Reliability requirements of the Largest Unit out of service and the remaining units handling 50% of the PDF, the chlorine feed rate should be adjusted to provide a minimum residual of the following: at 50% PDF 1 mg/L. • OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 13 of 14 4.0 MGD Determine flow rates for various trains beino removed from service for repair and maintenance: Volume, Min Flowrate, Trains Flow Condition gal Residual CT, min Flowrate, gpm MGD Comments T1 only at AADF 8,520 1.0 25 340.8 0.49 When AADF or PDF reaches these rates, at PDF 1.5 16.667 511.2 0.74 a second train shall be on line. T1 + T2 (or T3) at AADF 22,520 1.0 25 900.8 1.30 When AADF or PDF reaches these rates, at PDF 1.5 16.667 1,351.2 1.95 a third train shall be on line. T2 only at AADF 14,000 1.0 25 560.0 0.81 When AADF or PDF reaches these rates, at PDF 1.5 16.667 840.0 1.21 T3 shall be on line. T2 + T3 at AADF 28,000 1.0 25 1,120.0 1.61 When AADF or PDF reaches these rates, at PDF 1.5 16.667 1,680.0 2.42 T1 shall be added - all three trains on line. T1 + T2 + T3 at AADF 36,520 1.0 25 1,460.8 2.10 When AADF or PDF reaches these rates, at PDF 1.5 16.667 2,191.2 3.16 a fourth train shall be constructed. T1 + T2 + T3 + T4 at AADF 50,520 1.0 25 2,020.8 2.91 When AADF or PDF reaches these rates, at PDF 1.5 16.667 3,031.2 4.36 a fifth train shall be constructed. T1 + T2 + T3 + T4 at AADF 64,520 1.0 25 2,580.8 3.72 When AADF or PDF reaches these rates, + T5 at PDF 1.5 16.667 3,871.2 5.57 a sixth train shall be constructed. OK up to 3.0 MGD AADF and 6.0 MGD PDF T1 + T2 + T3 + T4 at AADF 78,520 1.0 25 3,140.8 4.52 + T5 + T6 at PDF 1.5 16.667 4,711.2 6.78 T1 + T2 + T3 + T4 at AADF 92,520 1.0 25 3,700.8 5.33 Seven trains are adequate for AADF and + T5 + T6 + T7 at PDF 1.5 16.667 5,551.2 7.99 PDF indicated. OUA Permit Renewal 7/16/2004 WWTP System Calculations Page 14 of 14 4.0 MGD APPENDIX B OPINION OF PROBABLE CONSTRUCTION COSTS • • 0 APPENDIX B - OPINION OF PROBABLE CONSTRUCTION COSTS OUA WWTP - CEMETERY ROAD ALTERNATIVES July 14, 2004 MASTER PUMP STATION Concrete 200 cy @ 450 = 90,000 Excavation/Stabilization 1 Is @ 50,000 = 50,000 Pumps, VFDs, Controls 1 Is @ 80,000 = 135,000 Piping 1 Is @ 75,000 = 120,000 Electrical 1 Is @ 80,000 = 80,000 SUBTOTAL 475,000 30% Contingency 1 Is @ 142,500 = 142,500 TOTAL 617,500 HEADWORKS 1. With In -Channel Grit Collector Concrete 250 cy @ 450 = 112,500 Bar Screen - Mechanical 1 Is @ - _ - Bar Screen - Manual 1 Is @ 10,000 = 10,000 Grit Collector 1 Is @ - _ - Parshall Flume/Flow Meter 1 Is @ 20,000 = 20,000 Gates 8 ea @ 3,000 = 24,000 Miscellaneous Piping 1 Is @ 50,000 = 50,000 Excavating/ Stabilization 1 Is @ 50,000 = 50,000 Electrical 1 Is @ 75,000 = 75,000 SUBTOTAL 341,500 (plus bar screen and grit collection) 2. With Free -Standing Grit Collector Concrete 175 cy @ 450 = 78,750 Bar Screen - Mechanical 1 Is @ - Bar Screen - Manual 1 Is @ 10,000 = 10,000 Grit Collector 1 Is @ - Parshall Flume/Flow Meter 1 Is @ 20,000 = 20,000 Gates 8 ea @ 3,000 = 24,000 Miscellaneous Piping 1 Is @ 50,000 = 50,000 Excavating/ Stabilization 1 Is @ 50,000 = 50,000 Electrical 1 Is @ 75,000 = 75,000 SUBTOTAL 307,750 (plus bar screen and grit collection) Based upon the selected Screening system and Grit Collector, the estimated cost for the Total Headworks is less than $800,000 total. 491 Appendix B Page 1 of 4 Pages 7/16/2004 AERATION BASIN 2.0 MGD OPTION 1. 2-Channel Option Aerators, Velocity Baffles 1 Is @ 208,500 = 208,500 Weatherhoods 1 Is @ 142,500 = 142,500 Concrete 1 Is @ 80,000 = 80,000 Walkways, Handrails 1 Is @ 20,000 = 20,000 Electrical 1 Is @ 50,000 = 50,000 SUBTOTAL = 501,000 30% Contingency 1 Is @ 150,300 = 150,300 TOTAL = 651,300 2. 3-Channel Option Aerators 1 Is @ 127,500 = 127,500 Weatherhoods 1 Is @ 127,500 = 127,500 Concrete 1 Is @ 275,000 = 275,000 Walkways, Handrails 1 Is @ 25,000 = 25,000 Electrical 1 Is @ 100,000 = 100,000 SUBTOTAL = 655,000 30% Contingency 1 Is @ 196,500 = 196,500 TOTAL = 851,500 3.0 MGD OPTION 1. 2 Channel Option + New 2 Channel Chamber From 1. above 1 Is @ 501,000 = 501,000 New Basin + Equipment, etc. 1 Is @ 1,152,100 = 1,152,100 (from previous bid and current equipment costs) SUBTOTAL = 1,653,100 30% Contingency 1 Is @ 495,930 = 495,930 TOTAL = 2,149,030 CLARIFICATION 2.0 MGD OPTION 1. Do Nothina TOTAL = - 3.0 MGD OPTION 1. New Clarifier Clarifier, Equipment, etc. 1 Is @ 450,000 = 450,000 (from previous bid + new equipment costs) SUBTOTAL = 450,000 30% Contingency 1 Is @ 135,000 = 135,000 TOTAL = 585,000 Appendix B Page 2 of 4 Pages 7/16/2004 • FILTRATION 2.0 MGD OPTION 1. US Filter Davis/DAVCO Install New Unit 1 Is @ 120,000 = Concrete Slab 20 cy @ 450 = Piping 1 Is @ 20,000 = Electrical 1 Is @ 50,000 = SUBTOTAL = 30% Contingency 1 Is @ 54,000 = TOTAL = 2. Parkson Smartfilter Travelinq Bridqe Filter Install New Unit 1 Is @ 187,500 = Concrete Slab 20 cy @ 450 = Piping 1 Is @ 20,000 = Electrical 1 Is @ 50,000 = SUBTOTAL = 30% Contingency 1 Is @ 79,950 = TOTAL = OPTIONS 3 - 7 REPLACE EXISTING FILTERS 3. Infilco-Dearemont Automatic Backwash Filter Concrete 250 cy @ 450 = Filters 1 Is @ 345,000 = • Piping 1 Is @ 50,000 Electrical 1 Is @ 75,000 = SUBTOTAL = 30% Contingency 1 Is @ 174,750 = TOTAL = 4. Sanitaire/ABJ Drum Filters Concrete Slab 26 cy @ 450 = Filters, Free Standing 1 Is @ 414,000 = Piping 1 Is @ 50,000 = Electrical 1 Is @ 75,000 = SUBTOTAL = 30% Contingency 1 Is @ 165,210 = TOTAL = 5. US Filter/Kruger Hvdrotech Discfilters Concrete Slab 32 cy @ 450 = Filters, Free Standing 1 Is @ 577,500 = Piping 1 Is @ 50,000 = Electrical 1 Is @ 75,000 = SUBTOTAL 30% Contingency 1 Is @ 215,070 = TOTAL • 120,000 9,000 20,000 31,000 180,000 54,000 234,000 187,500 9,000 20,000 50,000 266,500 79,950 346,450 112,500 345,000 50,000 75,000 582,500 174,750 757,250 11,700 414,000 50,000 75,000 550,700 165,210 715,910 14,400 577,500 50,000 75,000 716,900 215,070 931,970 Appendix B Page 3 of 4 Pages 7/16/2004 • 6. Parkson Dvnasand Filters Concrete 250 cy @ 450 = 112,500 Filter Modules 1 Is @ 420,000 = 420,000 Piping 1 Is @ 50,000 = 50,000 Electrical 1 Is @ 75,000 = 75,000 SUBTOTAL = 657,500 30% Contingency 1 Is @ 197,250 = 197,250 TOTAL = 854,750 7. Tetra Deer) Bed Filters Concrete 437 cy @ 450 = 196,650 Filter Modules 1 Is @ 697,500 = 697,500 Piping 1 Is @ 50,000 = 50,000 Electrical 1 Is @ 75,000 = 75,000 SUBTOTAL = 1,019,150 30% Contingency 1 Is @ 305,745 = 305,745 TOTAL = 1,324,895 EFFLUENT PUMPING. CHLORINE CONTACT AND CHLORINATION 1. Add On to Existinq Svstem Tanks 5 ea @ 10,000 = 50,000 Piping 1 Is @ 25,000 25,000 Electrical 1 Is @ 25,000 25,000 Monitoring Equipment 1 Is @ 10,000 = 10,000 SUBTOTAL = 110,000 30% Contingency 1 Is @ 33,000 = 33,000 TOTAL = 143,000 2. New Chlorine Contact Chamber and Effluent Pumr) Station Concrete 554 cy @ 450 = 249,300 Pumps, Drives 1 Is @ 100,000 = 100,000 Handrails, Grating 1 Is @ 80,000 = 80,000 Piping 1 Is @ 80,000 = 80,000 Electrical 1 Is @ 50,000 = 50,000 Excavation/Stabilization 1 Is @ 20,000 = 20,000 Chlorine Diffusers 1 Is @ 10,000 = 10,000 Flowmeter, Weir 1 Is @ 20,000 = 20,000 SUBTOTAL = 609,300 30% Contingency 1 Is @ 182,790 = 182,790 TOTAL = 792,090 MISCELLANEOUS Site Work, 5% of Subtotal Yard Piping, 15% of Subtotal Electrical, 15% of Subtotal Mobilization, 10% of Subtotal Appendix B Page 4 of 4 Pages 7/16/2004 TECHNICAL MEMORANDUM NO. 2 RESIDUALS MANAGEMENT July 2004 METZGER & WILLARD, INC. Civil • Environmental Engineers 8600 HIDDEN RIVER PARKWAY SUITE 550 TAMPA, FL 33637 913-977-6005 0 • TECHNICAL MEMORANDUM NO. 2 RESIDUALS MANAGEMENT TABLE OF CONTENTS SECTION DESCRIPTION PAGE 1. INTRODUCTION 1-1 2. SUMMARY OF EXISTING TREATMENT AND DISPOSAL 2-1 3. EXISTING REGULATIONS 3-1 FEDERAL 3-1 General Provisions 3-1 Land Application 3-1 Metals 3-1 Pathogens 3-3 Vector Attraction Reduction 3-3 Monitoring 3-3 Surface Disposal 3-4 Pollutant Limits 3-4 Pathogens 3-5 Vector Attraction Reduction 3-5 Air 3-5 Pathogens and Vector Attraction Reduction 3-5 Pathogens 3-6 Processes to Significantly Reduce Pathogens (PSRP) 3-7 Processes to Further Reduce Pathogens (PFRP) 3-8 Incineration 3-9 Landfill 3-10 STATE 3-10 Pathogen Reduction 3-11 Vector Attraction Reduction 3-11 Site Use Restrictions 3-11 Landfills 3-12 LOCAL 3-13 Okeechobee County Requirements 3-13 Land Application Sites for Class A and B Residuals and Septage 3-13 SECTION DESCRIPTION PAGE 4. CURRENT AND FUTURE QUANTITY AND QUALITY 4-1 EXISTING QUANTITY 4-1 FUTURE QUANTITY 4-1 ANTICIPATED QUALITY 4-1 5. POTENTIAL TREATMENT AND DISPOSAL STRATEGIES 5-1 RESIDUALS TREATMENT 5-1 ALKALINE STABILIZATION PROCESSES 5-1 BioSet System 5-3 FKC System — Class A 5-8 FKC System — Class B 5-12 COMPOSTING PROCESS 5-13 Parkson Corporation Therm o-System Solar Sludge Drying 5-13 EVALUATION OF PROCESSES 5-19 MATRIX EVALUATION 5-22 6. SELECTED PROGRAM FOR RESIDUALS MANAGEMENT 6-1 APPENDIX A. Opinion of Probable Construction Costs and Annual Operating Costs B. Demonstration Study Results C. Process Information BioSet FKC Thermo -System Centrifuge LIST OF FIGURES NUMBER DESCRIPTION PAGE 1-1 OUA Service Area 1-2 2-1 Residuals — Historical Flows, 1998-2003 2-2 2-2 Existing Residuals Management Pro gram 2-3 4-1 Projected Wastewater Flows, 2003-2016 4-9 4-2 Design Quantity for Resi duals Based Upon Projected Flows to WWTP 4-10 5-1 Typical Alkaline Treatment for Domestic Residuals 5-4 5-2 BioSet System 5-5 5-3 Site Schematic — BioSet System 5-6 5-4 FKC System — Class A 5-9 5-5 FKC Residuals Management System — Class A — Site Schematic 5-10 5-6 Thermo -System with Centrifuge 5-15 5-7 Thermo -System with Centrifuge — Site Schematic 5-16 5-8 Thermo -System with Drum Thickener — Site Schematic 5-17 5-9 Process Capital Costs 5-23 5-10 Annual Cost Comparison 5-24 5-11 Quantity of Residuals Produced Daily 5-26 6-1 Disposal Costs for Liquid and Dewatered Residuals 6-2 LIST OF TABLES NUMBER DESCRIPTION PAGE 1-1 Phosphorus Reduction to Lake Okeechobee as a Resul t of Providing a Regional Sewerage System to Areas Adjacent to the Lake 1-3 3-1 Ceiling Concentrations for Pollutants in Sewage Sludges 3-1 3-2 Cumulative Pollutant Loading Rates for Sewage Sludges 3-2 3-3 Pollutant Concentrations i n Sewage Sludges 3-2 3-4 Annual Pollutant Loading Rates for Sewage Sludges 3-3 3-5 Frequency of Monitoring for Land Applic ation of Sewage Sludges 3-4 3-6 Pollutant Concentrations — Active Sewage Sludge Unit without a Liner and Leachate Collection 3-4 3-7 Pollutant Concentrations —Active Sewage Sludge Unit without a Liner and Leachate Collection System that Has a Unit Boundary to the Property Li ne Less than 150 Meters 3-5 3-8 Pathogen Reduction Requirements for Class A and Class B Sewage Sludges 3-6 3-9 Chapter 62-640 — Descriptions of Cl ass A, AA and B Sewage Sludges (Residuals) 3-11 4-1 OUA Flow Data — Wastewater Treatment Facility 4-3 4-2 Projected Flows for OUA WWTP (2003-2016) 4-8 4-3 Projected Quality of Residuals 4-11 5-1 Residuals Treatment Options 5-1 5-2 Flow Rate Information — BioSet System 5-7 5-3 Flow Rate Information — FKC System — Class A 5-8 5-4 Flow Rate Information — FKC System — Class B 5-12 5-5 Breakdown of Costs for Phases I and II for FK C System — Class B 5-12 5-6 Flow Rate Information —Thermo-System with Centrifuge 5-18 5-7 Flow Rate Information — Thermo -System with Rotary Drum Thickener 5-18 5-8 Evaluation Matrix for Processes 5-21 5-9 Storage Requirements of Final Product 5-28 SECTION 1. INTRODUCTION In recent years, the Florida Department of Environmental Protection, the South Florida Water Management District, the US Army Corps of Engineers, the University of Florida — Institute of Food and Agricultural Studies, the Florida Department of Health and the Florida Department of Agricultural and Consumer Services have been studying Lake Okeechobee — the largest freshwater lake in Florida. The agencies have determined that phosphorus loadings within the Lake's watershed area have contributed to excessive phosphorus loadings within the Lake itself. High phosphorus levels lead to eutrophication which causes algal blooms, leadi ng to unpleasant tastes and odor s in potable water withdrawn from the Lake. The Lak a is a major source of revenue to the area for corn mercial and sport fishing. Eutrophication reduces the ability of fish and other aquatic species and plants to grow and repro duce properly. Many efforts have been extended by all of the above agencies to reduce the phosphor us levels in the Lake to a "background" level of 40 ppb. Many p rojects are being designed and constructed to red uce the quantity of phosphorus to this level. The Okeechobee Uti lity Authority (Authority) intends to continue to provide sewerage facilities to remove septic tanks and small package treatment facilities from the area adjacent to the Lake and within the service area of the Authority. The Authority's service area is illustrated in Figure 1-1. In December 2003, a repo rt entitled, Okeechobee Utility Authority Wastewater Facilities Plan, was completed by Metzger & Willard, Inc., and submitted to the Florida Department of Environmental Protection and the Authority. A s a part of the report, it was determined that by providing a regional sewage system for the collection, transmission, treatment and disposal to the areas adjacent to the Lake approximately 6 tons of phosphorus per year will be prevented from entering Lake Okeechobee, as shown in T able 1-1. Technical Memorandum No. 2 1-1 Okeechobee Utility Authority Residuals Management July 2004 7oks ?chobee mocks FIGURE 1-1 OUA SERVICE AREA METZGER & WILLARD, INC. Civil • Environmental Engineers T—pa, Aorido 33637 (813) 977-6005 • 0 TABLE 1-1. PHOSPHORUS REDUCTION TO LAKE OKEECHOBEE AS A RESULT OF PROVIDING A REGIONAL SEWERAGE SYSTEM TO AREAS ADJACENT TO THE LAKE, PHOSPHORUS REDUCTION, AREA FLOW, GPD TONS/YEAR * Taylor Creek Isles 246,900 1.54 Ousley Infill 12,400 0.08 Treasure Island 385,000 1.92 Big "O" 78,300 0.42 Buckhead Ridge 140,200 0.66 Ancient Oaks 156,040 0.73 Blue Cypress 57,800 0.27 TOTAL 1,076,640 5.62 =6 " Based upon 4.09 mg/L - Concentration reaching canals/Lake Okeechobee. Developed through literature search and sampling program in Okeechobee. (40% of value of septic tank effuent escaping into the soils.) r� • In order to provide adequate capacity at the A uthority wastewater treatment plant and to continue the program of phosphorus reduction to the Lake, the capacity will need to be increased. Therefore, this technical memorandum addresses the needs of residuals management for the expanded facility. Technical Memorandum No. 2 1-4 Okeechobee Utility Authority Residuals Management July 2004 • C] SECTION 2. SUMMARY OF EXISTING TREATMENT AND DISPOSAL SYSTEMS Domestic residuals are currently treated within the Authority's Cemetery Road wastewater treatment facility to Class B Standards, which allows for land application at public -access restricted sites. The residuals are treated by aerobic digestion to reduce pathogens and vector attraction. After treatment, the liquid residuals (approximatel y 1 percent solids) are then land applied at the wastewater treatment plant site or dewatered using rented equipment and taken to the Okeechobee County landfill for disposal. The facility processes approximately 100 dry tons per year of domestic residuals, including approximately 9.5 dry tons of residuals from Authority operated or contracted package facilities. Newly adopted setback requirements, provided in an Okeechobee County ordinance will prohibit the use of much of the FD EP-approved land application site at the Authority's Cemetery Road W WTP site. The Authority is considering additional residuals treatment — by dewatering and stabilization to reduce the quantity and improve the quality of the residuals to allow for land application to non -restricted sites (Class A or AA residuals). Upon expiration of the current FDEP operating permit in July 2008, the County setback requirements will take affect for the Authority site. Over one-half of the Authority site will then be restricted from use for Class B residuals. Currently, waste activated sludge is removed from the clarifiers at a rate of approximately 20,000 to 35,000 gpd (2700 — 4700 cubic feetiday) at 0.8 percent solids and pum ped to one of the two aerobic digesters. E ach digester can contain a volume of approximately 60,000 CF of residuals. The historical residuals flows are shown in Figure 2-1. Technical Memorandum No. 2 2-1 Okeechobee Utility Authority Residuals Management July 2004 O Oct-98 Jan-99 Apr-99 - Jul-99 - Oct-99 - Jan-00 - Apr-00 - Jul-00 Oct-oo Jan-01 - Apr-01 D Jul-o1 m Oct-01 Jan-02 - Apr-02 Jul-02 Oct-02 Jan-03 Apr-03 Jul-03 Oct-03 Jan-04 Apr-04 RESIDUALS FLOW, MGD o O o O 0 O O O N cn s CJt N U7 C m N X m v c D r N 2 -i O X n D r r O N cc cfl 00 N O O w AEROBIC DIGESTERS (2) VOLUME 60,320 CIF EACH I WAS 0 = 1,100 CF/DAY TS = 0.8% RESIDUALS VOLUME z 160,000 CF/YEAR TS = 2.0% +/- TRANSPORT INTERMITTENTLY ON SITE RES TRANS oo UU o 276 ACRES t LAND APPLICATION SITE TO LAND APPLICATION , ) „ 1 ZONES w u W NOTE: SYSTEM BASED UPON = 100 DRY TONS/YEAR RESIDUALS APPLICATION. FIGURE 2-2: EXISTING RESIDUALS MANAGEMENT PROGRAM METZGER & WILLARD, INC. Civil • £nvironmentol Engineers Tampa, Fl orido 33637 (813) 977-6005 The residuals are aerated for a period of at least 40 days with the supernatant returned to the head of the plant. Treated residuals are then removed from the digester to a tanker truck for applying to the surface of the disposal site. The existing program is illustrated in Figure 2-2. The disposal site i ncludes approximatel y 276 acres at the WWT P. As an alternate, the residuals are de -watered and taken to the Okeechobee C ounty Landfill for disposal. Technical Memorandum No. 2 2-4 Okeechobee Utility Authority Residuals Management July 2004 • • Federal SECTION 3. EXISTING REGULATIONS The appropriate federal regulations include 40CFR Part 503 — Standards for the Use or Disposal of Sewage Sludge and 40 CFR Part 258 — Criteria for Municipal Solid Waste Landfills. GENERAL PROVISIONS Part 503 establishes "standards, which consist of general requirements, pollutant limits, management practices, and operational standards, for the fin al use or disposal of sewage sludge generated during the treatment of domestic sewage in a treatment works." T he use and disposal includes sewage sludge appli ed to the land, placed on a surface disposal site or fired in an incinerator. Sewage sludge taken to a landfill is covered by 40CFR Part 258. LAND APPLICATION Part 503 provides for the following pollutant limits (503.13) — both concentrations and loading rates, where land application is the method of disposal. Metals: (1) For bulk sewage sl udge to be marketed or distributed, pollutant levels may not exceed those listed in Table 3-1. TABLE 3-1. CEILING CONCENTRATIONS FOR POLLUTANTS IN SEWAGE SLUDGES. POLLUTANT Arsenic Cadmium Copper Lead Mercury Molybdenum Nickel Selenium Zinc Technical Memorandum No. 2 Residuals Management CEILING CONCETRATION (MG/KG — DRY WEIGHT BASIS) 75 85 4300 840 57 75 420 100 7500 3-1 Okeechobee Utility Authority July 2004 (2) For application to agricultural land, forest, a public contact site, or a re clamation site, the cumulative loading rate cannot exceed the following loading rates in Table 3-2, or the concentrations for the pollutants provided in Table 3-3. TABLE 3-2. CUMULATIVE POLLUTANT LOADING RATES FOR SEWAGE SLUDGES. POLLUTANT Arsenic Cadmium Copper Lead Mercury Molybdenum Nickel Selenium Zinc CUMULATIVE POLLUTANT LOADING RATE (KG/HECTARE) 41 39 1500 300 17 N/A 420 100 2800 TABLE 3-3. POLLUTANT CONCENTRATIONS IN SEWAGE SLUDGES. POLLUTANT MONTHLY AVERAGE CONCENTRATION (MG/KG — DRY WEIGHT BASIS) Arsenic 41 Cadmium 39 Copper 1500 Lead 300 Mercury 17 Molybdenum N/A Nickel 420 Selenium 100 Zinc 2800 (3) For application to a lawn or home garden, the concentration of each parameter may not exceed those listed in Table 3-3. (4) For sewage sludge sold or given away for application to land (marketed and distributed in containers, but not bulk), the concentration of each pollutant in the sewage sludge shall not exceed the concentrations in Table 3-3, or the product of the concentration of each pollutant in the sewage sludge and the annual whole s ludge application rate for the sewage sludge shall not cause the annual pollutant loading rate for the pollutants in Table 3-4 to be exceeded. Technical Memorandum No. 2 3-2 Okeechobee Utility Authority Residuals Management July 2004 TABLE 3-4. ANNUAL POLLUTANT LOADING RATES FOR SEWAGE SLUDGES. POLLUTANT Arsenic Cadmium Copper Lead Mercury Molybdenum Nickel Selenium Zinc ANNUAL POLLUTANT LOADING RATE (KG/HECTARE PER 365 DAY PERIOD) 2.0 1.9 75 15 0.85 N/A 21 5.0 140 Pathogens: The Class A pathogen requirements in 503.32(a) or the Class B pathogen requirements and site restrictions in 503.32(b) are required to be met when bulk sewage sludge is applied to agricultural land, forest, a public contact site, or a reclamation site. The Class A pathogen requirements are r equired to be met when bulk sew age sludge is applied to a lawn or home garden. The Class A pathogen requirements are required to be met when sewage sl udge (not bulk) is sold or given away in a bag or other container for application to the land. Vector Attraction Reduction: One of the vector attraction reduction require ments provided in Part 503.33(b)(1) through (b)(10) shall be met for any of the above three uses for sludge is performed. Additional information on Pathogen and Vector Attraction Reduction is provided further in this Section of the report. Monitoring: The frequency of monitoring for the pollutants listed in Tables 3-1, 3-2, 3-3 and 3-4; the pathogen density requirements; and the vector attr action reduction levels are as provided in Table 3-5. Technical Memorandum No. 2 3-3 Okeechobee Utility Authority Residuals Management July 2004 TABLE 3-5. FREQUENCY OF MONITORING FOR LAND APPLICATION OF SEWAGE SLUDGES. AMOUNT OF SEWAGE SLUDGE (METRIC TONS FREQUENCY PER 365 DAY PERIOD) Greater than zero but le ss than 290 Once per year Equal to or greater than 290, but less than 1500 Once per quarter (four times per year) Equal to or greater than 1500, but less than 15,0 00 Once per 60 days (six times per year) Equal to or greater than 15,000 Once per month (12 times per year) After the sewage sludge has been monitored for two years, the permitting authority may reduce the frequency of the testing. SURFACE DISPOSAL Part 503.20 is appropriate for where sewage sludge is placed on a surface disposal site. The land where the sludg a is placed is used only for the placement of sewage sludge. Leachate may be collected for treatment. Pollutant Limits: For an active sewage unit without a liner and a leachate collection system, the concentration of each pollutant listed in Table 3-6 shall not be exceeded. TABLE 3-6. POLLUTANT CONCENTRATIONS —ACTIVE SEWAGE SLUDGE UNIT WITHOUT A LINER AND LEACHATE COLLECTION. POLLUTANT CEILING CONCETRATION (MG/KG — DRY WEIGHT BASIS) Arsenic 73 Chromium 600 Nickel 420 For surface disposal sites where there is less than 150 meters to the property line, the pollutant concentrations decrease as shown in Table 3-7. Technical Memorandum No. 2 3-4 Okeechobee Utility Authority Residuals Management July 2004 Pathoqens: For the removal of pathogens from sewage sludge, the following requirements listed in Table 3-8 are necessary to meet the Class A and Class B regulations. TABLE 3-8. PATHOGEN REDUCTION REQUIREMENTS FOR CLASS A AND CLASS B SEWAGE SLUDGES. Class A Density of fecal coliform in the sewage sludge shall be less than 1000 MPN per gram of total solids (dry weight basis) OR Density of Salmonella sp. bacteria in the sewage sludge shall be less than three MPN per four grams of total solids (dry weight basis) at the time the sewage sludge is used or disposed; at the time the sewage sludge is prepared for sale or give away in a bag or other container for application to the land; or at the time the sewage sludge or material derived from sewage sludge is prepared to meet the requirements for bulk sewage sludge disposal. Alt 1. I The temperature of the sewage sludge that is used or disposed shall be maintained at a specific value for a period of time. 7% or hiaher solids of sewaqe sludqe: Shall be 50 degrees C or higher for 20 minutes or longer. The temperature and time period are determined using the following equation: D = 131,700,000/100'1400t Where, D = time in days t = temperature in degrees C 7% or hiqher solids and small particles of sewaqe sludge are heated by either warmed qases or an immiscible liquid: Shall be 50 degrees C or higher for 15 seconds or longer. The temperature and time period shall be determined using the above formula. < 7% and the time period is at least 15 seconds, but less than 30 minutes: The temperature and time period shall be determined using the above formula. < 7%, temperature is 50 degrees C or higher, and the time Deriod is 30 minutes or longer: The temperature and time period shall be determined using the following equation: D = 50,070,000/100.14001 Where, Technical Memorandum No. 2 Residuals Management D = time in days t = temperature in degrees C 3-6 Okeechobee Utility Authority July 2004 • • TABLE 3-7. POLLUTANT CONCENTRATIONS — ACTIVE SEWAGE UNIT WITHOUT A LINER AND LEACHATE COLLECTION SYSTEM THAT HAS A UNIT BOUNDARY TO THE PROPERTY LINE LESS THAN 150 METERS. Unit boundary to property line Pollutant concentration Distance (meters) 0 to less than 25 25 to less than 50 50 to less than 75 75 to less than 100 100 to less than 125 125 to less than 150 Chromium Arsenic (mg/kg) (mg/kg) Nickel (mg/kgL_ 30 200 210 34 220 240 39 260 270 46 300 320 53 360 390 62 450 420 A sewage sludge unit suitable for surface dispos al is similar to a sanitary landfill. The sludge is covered and the site is eventually "closed" in a fashion similar to a landfill. In addition, after the site is closed, monitoring is required for a period of time. Ground water monitoring is required and site restrictions for use are required. The frequency of monitoring is simil ar to a land application site. Pathogens: The Class A pathogen requirements or one of the Class B pathogen requirements are required to be met when sewage sludge is placed on an active sewage sludge unit, unless the vector attraction reduction requirement is met. Vector Attraction Reductions: One of the vector attraction reduction requ irements is necessary to be met when s ewage sludge is placed in an active sewage sludge unit. Air: In addition to the other monitoring requirements, the air in buildings and structures is required to be monitored continuou sly for methane gas while the system is in operation and for a period of three years after the site is c losed. PATHOGENS AND VECTOR ATTRACTION REDUCTION As defined in Part 503.31, pathogenic organisms are disease -causing org anisms, and include certain bacteria, protozoa, viruses, viable helminth ova, and other organisms. In addition, vector attraction is the characteristic of sewage sludge that "attracts rodents, flies, mosquitoes, or other organisms capable of transporting infectious agents". Technical Memorandum No. 2 3-5 Okeechobee Utility Authority Residuals Management July 2004 TABLE 3-8. PATHOGEN REDUCTION REQUIREMENTS FOR CLASS A AND CLASS B SEWAGE SLUDGES. Alt 2. 1 The pH of the sewage sludge that is used or disposed shall be raised to above 12 and shall remain above 12 for 72 hours. Class B Alt 3. The temperature of the sewage sludge shall be above 52 degrees C for 12 hours or longer during the period that the pH of the sewage sludge is above 12. At the end of the 72 hour period during which the pH of the sewage sludge is above 12, the sewage sludge shall be air dried to achieve a percent solids in the sewage sludge greater than 50 percent. Enteric Viruses: The sewage sludge shall be analyzed prior to pathogen treatment to determine whether the sewage sludge contains enteric viruses. <1: If the density is less than one Plaque -forming Unit per four grams of total solids (dry weight basis), the sewage sludge is Class A with respect to enteric viruses until the next monitoring episode for the sewage sludge. Helminth Ova: <1: If the density is less than one per four grams of total solids (dry weight basis) after pathogen treatment, the sewage sludge is Class A with respect to viable helminth ova density. Alt 4. The requirements for Alt 4 are the same as for Alt 3, unless otherwise specified by the permitting authority. Alt 5. Sewage sludge that is used or disposed shall be treated in one of the Processes to Further Reduce Pathogens as defined later in this report. Alt 6. Sewage sludge that is used or disposed shall be treated in a process that is equivalent to a Process to Further Reduce Pathogens, as determined by the permitting authority. One of the following requirements for pathogens shall be met before sewage sludge can be labeled as Class B. Alt 1. Seven samples of the sewage sludge shall be collected. The geometric mean in the samples collected shall be less than either 2,000,000 Most Probable Number per gram of total solids (dry weight basis) or 2,000,000 Colony Forming Units per gram of total solids (dry weight basis) Alt 2. Sewage sludge that is used or disposed shall be treated in one of the Processes to Significantly Reduce Pathogens described later in this report. Alt 3. Sewage sludge that is used or disposed shall be treated in a process that is equivalent to a Process to Significantly Reduce Pathogens, as determined by the permitting authority. Site Restrictions: Site restrictions regarding crops, harvest dates, animal grazing, public access and other issues shall be met when sewage sludge that meets the above Class B pathogen requirements are to be applied to land. Processes to Significantly Reduce Pathoaens (PSRP): The following is a list of processes to significantly reduce pathogens in sewage sl udge. Technical Memorandum No. 2 3-7 Okeechobee Utility Authority Residuals Management July 2004 1. Aerobic digestion: Sewage sludge is agitated with air or oxygen to maintain aerobic conditions for a specific mean cell residence time at a specific temperature. Values for the mean cell residence time and temperature shall be between 40 days at 20 degrees C and 60 days at 15 degrees C. 2. Air drying: Sewage sludge is dried on sand beds or on paved or unpaved basins. The sewage sludge dries for a minimum of three months. During two of the three months, the ambient average daily temperature is above zero degrees C. 3. Anaerobic digestion: Sewage sludge is treated in the absence of air for a specific mean cell residence time at a specific temperature. Values shall be between 15 days at 35 to 55 degrees C and 60 days at 20 degrees C. 4. Composting: Using either within -vessel, static aerated pile, or windrow composting methods, the temperature of the sewage sludge is raised to 40 degrees C or higher and remains at 40 degrees C or higher for five days. For four hours during the five days, the temperature in the compost pile exceeds 55 degrees C. 5. Lime stabilization: Sufficient lime is added to the sewage sludge to raise the pH of the sewage sludge to 12 after two hours of contact. Processes to Further Reduce Pathoaens (PFRP): The following is a list of processes to further reduce the pathogen density i n sewage sludge. 1. Composting: For the within -vessel composting method or the static aerated pile composting method, the temperature of the sewage sludge is maintained at 55 degrees or higher for three days. For the windrow composting method, the temperature of the sewage sludge is maintained at 55 degrees or higher for 15 days or longer. During the period when the compost is maintained at 55 degrees or higher, there shall be a minimum of five turnings of the windrow. 2. Heat drying: Sewage sludge is dried by direct or indirect contact with hot gases to reduce the moisture content of the sewage sludge to 10 percent or lower. Either the temperature of the sewage sludge particles exceeds 80 degrees C or the wet bulb temperature of the gas in contact with the sewage sludge as the sewage sludge leaves the dryer exceeds 80 degrees C. 3. Heat treatment: Liquid sewage sludge is heated to a temperature of 180 degrees C or higher for 30 minutes. 4. Thermophillic aerobic digestion: Liquid sewage sludge is agitated with air or oxygen to maintain aerobic conditions and the mean cell residence time of the sewage sludge is 10 days at 55 to 60 degrees C. 5. Beta ray irradiation: Sewage sludge is irradiated with beta rays from an accelerator at dosages of at least 1.0 megarad at room temperature (+/- 20 degrees C). 6. Gamma ray irradiation: Sewage sludge is irradiated with gamma rays from certain isotopes, such as 60Cobalt and 13'Cesium, at dosages of at least 1.0 megarad at room temperature (+/-20 degrees C). 7. Pasteurization: The temperature of the sewage sludge is maintained at 70 degrees C or higher for 30 minutes or longer. Technical Memorandum No. 2 3-8 Okeechobee Utility Authority Residuals Management July 2004 The vector attraction reduction requirements apply to bulk sewage sludge applied to agricultural lands, forests, public contact sites or reclamation sites. The rules apply also to bulk sewage sludge applied to lawn or home gardens. The rules also are appropriate for sewage sludge sold or given away in bags or other containers (not bulk) and for sludge placed in an active sewage sludge unit (surface disposal). Vector attracti on reduction is demonstrated by one of the following items. 1. Mass of volatile solids in sewage sludge shall be reduced by a minimum of 38 percent. 2. If (1) cannot be met, a laboratory bench scale study of anaerobically digested sewage sludge is performed for a minimum of 40 additional days at between 30 and 37 degrees C. If at the end of the 40 days, the volatile solids in the sewage sludge are reduced by less than 17 percent, vector attraction reduction is achieved. 3. If (1) cannot be met, a laboratory bench scale study of aerobically digested sewage sludge is performed for a minimum of 30 additional days at 20 degrees C. If at the end of the 30 days, the volatile solids in the sewage sludge are reduced by less than 15 percent, vector attraction reduction is achieved. 4. The specific oxygen uptake rate (SOUR) of aerobically digested sludge is equal to or less than 1.5 mg of oxygen per hour per gram of total solids (dry weight basis) at 20 degrees C. 5. Sewage sludge treated in an aerobic digester for 14 days or longer at 40 degrees C with an average temperature greater than 45 degrees C. 6. The pH of sewage sludge shall be raised to 12 or higher by alkali addition and shall remain at 12 or higher for an additional 72 hours. 7. The percent solids of sewage sludge that does not contain unstabilized solids generated in a primary wastewater treatment process shall be equal to or greater than 75 percent based upon the moisture content and total solids prior to mixing with other materials. 8. The percent solids of sewage sludge that does contain unstabilized solids generated in a primary wastewater treatment process shall be equal to or greater than 90 percent based upon the moisture content and total solids prior to mixing with other materials. 9. Sewage sludge shall be injected below the surface of the land. 10. Sewage sludge applied to the land surface or to an active sewage sludge unit shall be incorporated into the soil within six hours after application or placement, unless otherwise specified by the permitting authority. 11. Sewage sludge placed on an active sewage sludge unit shall be covered with soil or other material at the end of each operating day. INCINERATION: Part 503 provides for the requiremen is for sewage sludge incineration; however, this report will not address incineration as a disposal method, si nce it is a non -beneficial use of a Technical Memorandum No. 2 3-9 Okeechobee Utility Authority Residuals Management July 2004 0 • valuable product. Severe water and air quality standards apply to the incineration of sewage sludge. LANDFILL: Part 258 — Criteria for Municipal Solid Waste Landfills — applies to the disposal of sewage sludge in a sanitary landfill. This regulation provides for the permitting and monitoring of municipal solid waste landfills and defines the materials that may be disposed of within a landfill. Sewage sludge that is determined to be non -hazardous may be placed in a landfill. Local ordinances may provide more stringent requirem ents on local landfills. State The Florida Department of Environmental Protection regulates the management, use, and land application of residuals so as to "ensure protection of the environment and public health." Chapter 62-640 FAC — Domestic Wastewater Residuals is the rule governing domestic wastewater residuals. Chapter 62-640 provides the minimum standards "for the treatment of residuals and septage to be applied to land or d istributed and marketed, establish land application criteria, and define requirements for agricultural operations whic h have received or wi II receive residuals or septage." The FDEP (Chapter 62-640) defines the classes of residuals as follows: Class A: Residuals that meet all the requirements of Rul a 62-640.600(1)(a), as provided in Table 3-9. Class AA: Class A residuals that meet all the requirements of Rule 62-640.850, as provided in Table 3-9. Class B: Residuals that meet the Class B pathogen reduction requirements of Rule 62- 640.600(1)(b), as provided in Table 3-9. All land application sites used for the disposal of sewage sludge ( residuals) is required to submit an Agricultural Use Plan (AU P), with updates as required, prior to using the site for land application. The AUPs describes how the site meets regulations, establishes the location of each application zone, and provides a nutrient balanc a for the site. The AUP also projects the life of the site for the use of land application. Some areas, including areas Technical Memorandum No. 2 3-10 Okeechobee Utility Authority Residuals Management July 2004 within the Lake Okeechobee Watershed have been determ ined to be subject to restrictions on phosphorus loadings. The AUP also considers the potential for phosphorus movement from the site by considering the soils. TABLE 3-9. CHAPTER 62-640 DESCRIPTIONS OF CLASS A, AA AND B SEWAGE SLUDGES (RESIDUALS). CLASS A Same as the Federal regulations defined in Part 503 of 40 CFR, if one of the pathogen reduction requirements is met. CLASS AA 1. Shall meet the requirements for Class A pathogen reduction standards. 2. Shall meet one of the vector attraction reduction requirements of 40CFR Part 503. 3. Shall be analyzed in accordance with Rule 62-640.650(1) on a monthly basis and the results submitted to FDEP. The residuals products shall have monthly average parameter concentrations not exceeding the following criteria: MONTHLY AVERAGE PARAMETER (MG/KG DRY WEIGHT BASIS) Arsenic 41 Cadmium 39 Copper 1500 Lead 300 Mercury 17 Nickel 420 Selenium 100 Zinc 2800 OUA (Jan 1, 2004) (MG/KG DRY WEIGHT BASIS) 4.8 2.9 670 39 0.99 22 10 930 CLASS B Same as the Federal regulations as defined in Part 503 of 40 CFR, if one of the pathogen reduction requirements is met. PATHOGEN REDUCTION: Pathogen reduction requirements are the same as for the Federal Guidelines as described in Table 3-8. VECTOR ATTRACTION REDUCTION: All residuals applied to I and shall meet one of the vector attraction requirements provided by the Federal regulations and as described previously. Technical Memorandum No. 2 3-11 Okeechobee Utility Authority Residuals Management July 2004 SITE USE RESTRICTIONS: The following site use restrictions apply for the use of Classes AA, A and B residuals. CLASS AA/A Allowed on unrestricted public access areas such as playgrounds, parks, golf courses, lawns, and hospital grounds. CLASS B Not allowed on unrestricted public access areas. Limited to use on restricted public access areas such as agricultural sites, forests, and roadway shoulders and medians. The public shall be restricted from the application zone for 12 months after the last application of residuals. The following restrictions also apply: 1. Plant nursery: Limited to plants which will not be sold to the public for 12 months after the last application of residuals. 2. Roadway shoulders and medians: Limited to restricted public access roads. 3. Food crops with harvested parts that touch the residuals/soil mixture and are totally above the land surface: May not be harvested for 14 months after the last application. 4. Food crops with harvested parts below the surface of the land and residuals remain on the land surface for four months or longer before incorporation into the soil: May not be harvested for 20 months after the last application. 5. Food crops with harvested parts below the surface of the land and residuals remain on the land surface for less than four months before incorporation into the soil: May not be harvested for 38 months after the last application. 6. Food crops, feed crops, and fiber crops: May not be harvested for 30 days following the last application. 7. Animals: May not be grazed on the land for 30 days after the last application. 8. Sod which will be distributed or sold to the public or used on unrestricted public access areas: May not be harvested for 12 months after the last application. 9. Minimum setback distances: Stringent setback distances shall be adhered to as defined within the rule for land application areas and a building occupied by the general public. LANDFILLS: The FDEP (Chapter 62-701) provides the rules for the establishment, operation and closure of solid waste management facilities. Chapter 62-701 does not prohibit the placement of "sludge" within a landfill. In Chapter 62-701, sludge is defined as a" solid waste pollution control residual which i s generated by any ... domestic wastewater treatment plant ... " Technical Memorandum No. 2 3-12 Okeechobee Utility Authority Residuals Management July 2004 Local OKEECHOBEE COUNTY REQUIREMENTS: In 2003, the Okeechobee County Board of County Commissioners passed ordinance number 2003-06, which amends the County Land Development Regulations (LDRs), "providing for the protection of the ground and surface waters of Okeechobee County from the improper disposal of Class A and B residuals and septage". In general, the ordinance provides for the following: 1. Limits land application of Class A and B residuals and septage; 2. Requires submittal of Agricultural Use plans; 3. Requires permits for vehicles used to transport and apply residuals; 4. Requires annual perm its for land application sites; and, 5. Provides for other administrative requirements. The County defines Class A and B residuals in terms of the State definitions. Land Application Sites for Class A and B Residuals and SeDtage: Owners of property used for land application are required to obtain a permit from the Okeechobee County Heal th Department (OCH D) — which requires submitting a form and an AU P in accordance with FDEP form 62-640.210(2)(a) and the submittal of a fee. Permits are valid from October 1 through September 30. Only permitted vehicles can deliver/land apply residuals on the site. Residuals and septage must be treated to reduce pathogens and achi eve vector attraction reduction in accordance with state regulations prior to land applicati on. For residuals or septage exceeding three percent solids, the material must be tilled into the soil, land spread using a spreader bar, or otherwise disposed of in a manner approved by the OCH D within 24 hours of being placed on the site. No residuals or septage can be a pplied within 750 feet of an adjoining property unless the adjoining property is also land applying. The County ordinance requires a monthly report to the OCHD of the amount and source of the mater ial land spread. The report should als o include the pounds of nitrogen and phosphorus ap plied per acre and the location within the site where the residuals were applied. Technical Memorandum No. 2 3-13 Okeechobee Utility Authority Residuals Management July 2004 SECTION 4. CURRENT AND FUTURE QUANTITY AND QUALITY Existinq Quantitv In September 1998, the existing Authority plant on Cemetery Road was placed on-line. At that time, the older (1985) contact stabilization activated sludge (CSAS) facility was taken off-line for maintenance and repairs. Currently, the existing CSAS facility remains off-line. Historical flows at the existing WWTP are shown in Table 4-1 (October 1998 through June 2004). The facility is designed to waste approximately 2.7 percent of WAS daily (2.7% of total flow to the plant). Future Quantity Projected flows were developed for the wastewater plant, based upon system growth anticipated from infill, inclusion of existing package plants that are removed from service and collection system expansion. The system expansion schedule and projected flows are shown in Table 4-2 and illustrated in Figure 4-1. Based upon projected flows to the wastewater treatment plant, the projected quantity of residuals is shown in Figure 4-2. The quantity of residuals is based upon 4500 pounds BOD removed per day and 3600 pounds of solids wasted per day in the treatment process. Anticipated Qualitv It is anticipated that the quality of the residuals at the OUA wastewater treatment facility will remain fairly consistent, provided no new industries develop i n the area that could impact the quality of the residuals. Table 4-3 summarizes the anticipated quality which is within the Class A requirements for all param eters except for Molybdenum. The operations staff has been making an effort to determine the source of the Molybdenum and to remove it from the waste stream. The Molybdenum appears intermittently in the residuals and tracking down the source has been difficult. Technical Memorandum No. 2 4-1 Okeechobee Utility Authority Residuals Management July 2004 TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY MONTHLY 3-MONTH RUNNING ANNUAL 3 MONTH AVERAGE AS % DATE AVERAGE, MGD AVERAGE, MGD AVG, MGD DESIGN CAPACITY Oct-98 0.448 0.448 Nov-98 0.522 0.485 Dec-98 0.500 0.490 0.490 44.5 Jan-99 0.548 0.523 0.505 47.6 Feb-99 0.647 0.565 0.533 51.4 Mar-99 0.663 0.619 0.555 56.3 Apr-99 0.595 0.635 0.560 57.7 May-99 0.492 0.583 0.552 53.0 Jun-99 0.668 0.585 0.565 53.2 Jul-99 0.560 0.573 0.564 52.1 Aug-99 0.545 0.591 0.563 53.7 Sep-99 0.747 0.617 0.578 56.1 Oct-99 0.701 0.664 0.599 60.4 Nov-99 0.611 0.686 0.606 62.4 Dec-99 0.555 0.622 0.611 56.6 Jan-00 0.593 0.586 0.615 53.3 Feb-00 0.643 0.597 0.614 54.3 Mar-00 0.569 0.602 0.607 54.7 Apr-00 0.509 0.574 0.599 52.2 May-00 0.481 0.520 0.599 47.2 Jun-00 0.476 0.489 0.583 44.4 Jul-00 0.494 0.484 0.577 44.0 Aug-00 0.446 0.472 0.569 42.9 Sep-00 0.564 0.501 0.554 45.6 Oct-00 0.546 0.519 0.541 47.2 Nov-00 0.532 0.547 0.534 49.8 Dec-00 0.483 0.520 0.528 47.3 Jan-01 0.570 0.528 0.526 48.0 Feb-01 0.591 0.548 0.522 49.8 Mar-01 0.678 0.613 0.531 55.7 Apr-01 0.646 0.638 0.542 58.0 May-01 0.658 0.661 0.557 60.1 Jun-01 0.704 0.669 0.576 60.8 Jul-01 0.724 0.695 0.595 63.2 Aug-01 0.648 0.692 0.612 62.9 Sep-01 0.780 0.717 0.630 65.2 Oct-01 0.702 0.710 0.643 64.5 Nov-01 0.649 0.710 0.653 64.6 Dec-01 0.567 0.639 0.660 58.1 Table 4-1 7/16/2004 • • TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY DATE Jan-02 Feb-02 Mar-02 Apr-02 May-02 Jun-02 Jul-02 Aug-02 Sep-02 Oct-02 Nov-02 Dec-02 Jan-03 Feb-03 Mar-03 Apr-03 May-03 Jun-03 Jul-03 Aug-03 Sep-03 Oct-03 Nov-03 Dec-03 Jan-04 Feb-04 Mar-04 Apr-04 May-04 Jun-04 MONTHLY AVERAGE, MGD 0.601 0.612 0.567 0.533 0.483 0.493 0.618 0.552 0.660 0.608 0.622 0.735 0.777 0.729 0.711 0.660 0.638 0.696 0.656 0.815 0.766 0.716 0.696 0.666 0.685 0.716 0.683 0.658 0.631 0.616 3-MONTH AVERAGE,MGD 0.606 0.593 0.593 0.571 0.528 0.503 0.531 0.554 0.610 0.607 0.630 0.655 0.711 0.747 0.739 0.700 0.670 0.665 0.663 0.722 0.746 0.766 0.726 0.693 0.682 0.689 0.695 0.686 0.657 0.635 RUNNING ANNUAL AVG, MGD 0.662 0.664 0.655 0.645 0.631 0.613 0.604 0.596 0.586 0.579 0.576 0.590 0.605 0.615 0.627 0.637 0.650 0.667 0.670 0.692 0.701 0.710 0.716 0.711 0.703 0.702 0.699 0.699 0.699 0.692 3 MONTH AVERAGE AS % DESIGN CAPACITY 55.1 53.9 53.9 51.9 48.0 45.7 48.3 50.4 55.5 55.2 57.3 59.5 64.7 67.9 67.2 63.6 60.9 60.4 60.3 65.7 67.8 69.6 66.0 63.0 62.0 62.6 63.2 62.3 59.8 57.7 Table 4-1 7/16/2004 TABLE 4-2. PROJECTED FLOWS FOR OUA WWTP (2003-2016) MAKMO . > ; • ;.. , y nd;vf Year 2003 2004'y. 2005 '2006 2007: 2008, - 2009 2010' 2011 2012 2013 2014 2015 2016 Taylor Creek Isles 122,500 122,500 Ousley Infill 10,000 10,000 10,000 10,000 Treasure Island 112,000 223,000 50,000 SW (160 units) 30,000 10,000 SE (1000 units) 25,000 37,500 50,000 62,500 50,000 25,000 NE (300 units) 25,000 50,000 Misc Projects 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 Other Growth 19,150 22,691 27,696 33,563 43,040 47,491 51,116 54,269 56,875 58,922 61,020 63,171 65,375 TOTAL for YEAR, GPD1 141,650 200,191 234,696 379,063 178,040 144,991 126,116 104,269 81,875 83,922 86,020 88,171 90,375 AVERAGE DAY, GP 766,000 907,650 1,107,841 1,342,537 1,721,601 1,899,641 2,044,632 2,170,748 2,275,016 2,356,892 2,440,814 2,526,834 2,615,005 2,705,380 MAXIMUM DAY, GP 1,149,000 1,406,858 1,717,154 2,080,933 2,668,481 2,944,443 3,169,179 3,364,659 3,526,275 3,653,182 3,783,262 3,916,593 4,053,258 4,193,339 • 7/16/2004 3,000,000 2,500,000 2,000,000 0 a O 3 1,500,000 O J LL S 1,000, 000 500,000 0 1 O O O O N N FIGURE 4-1. PROJECTED WASTEWATER FLOWS, 2003 - 2016 Lo (D r- co O O N cM '7 Lo CO O O O O O O O O O O O O O O O O O N N N N N N N N N N N N END OF YEAR • • 180,000 160,000 140,000 0 a 0 120,000 J Q 0 100,000 w w U. O 80,000 H z 60,000 C 40,000 20,000 0 2003 FIGURE 4-2. RESIDUALS QUANTITY BASED UPON PROJECTED FLOWS TO WWTP 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 END OF YEAR 0 • • • TABLE 4-3. PROJECTED QUALITY OF RESIDUALS PARAMETER UNIT Total Nitrogen TN % Total Phosphorus TP % Total Potassium TK % Total Solids TS % Arsenic As mg/kg Cadmium Cd mg/kg Copper Cu mg/kg Lead Pb mg/kg Mercury Hg mg/kg Molybdenum Mb mg/kg Nickel Ni mg/kg Selenium Se mg/kg Zinc Zn mq/kg AVERAGE VALUE CLASS A * 2003 2002 2001 PROJECTED REGULATIONS 5.05 4.35 4.1 4.50 3.45 2.3 3.2 2.98 0.54 0.48 0.5 0.51 1.46 1.38 1.4 1.41 11.75 19 27 19 41 3.45 4.075 3.7 3.74 39 650 612.5 730 664 1500 35.25 39.25 47 41 300 1.4 2.3 5 2.9 17 71 61.8 124.5 86 24.2 57.8 145.5 76 420 14 24 27 22 100 810 790 932.5 844 2800 * Monthly Average Concentration (mg/kg dry weight basis) E • SECTION 5. POTENTIAL TREATMENT AND DISPOSAL STRATEGIES Residuals Treatment Based upon prior research and investigati ons, four options were considered for purposes of this evaluation as follows: TABLE 5-1. RESIDUALS TREATMENT OPTIONS. OPTION RESIDUALS TREATMENT LEVEL 1. Aerobic Digestion — Expand the existing Class B system 2. BioSet System — Schwing Bioset Class A Technologies, Danbury CT 3a. FKC System — FKC Co., Ltd., Port Class A Angeles, WA 3b. FKC System — FKC Co., Ltd, Port Class B Angeles, WA 4. Thermo -System — Parkson Corporation, Class A Ft. Lauderdale FL To continue with aerobic digesti on for the expanded facil ity, a third digester is required; however, the level of treatment will only provide a Class B residual. The Authority has chosen to go to the higher level of treatment, since the permitting and disposal requirements are less stringent on the material. Therefore, aerobic digestion will not be considered further. The remaining process es incorporate either alkali ne stabilization or composting. The following description and analysis is provided for each. Alkaline Stabilization Processes Part 503 requires that wastewater sol ids be processed or stabilized before they can be beneficially used. Stabilization helps to minimize the potential for odor generation, destroys pathogens and reduces the material's vector attraction potential. Class A biosolids are generally used like any commercial fertilizer. An alkaline material, usually lime, is mixed into the residuals where the pH can be maintained at or above 12 for a period of time that is dependent upon to mperature. The Technical Memorandum No. 2 5-1 Okeechobee Utility Authority Residuals Management July 2004 higher the temperature within the residuals maintained, the shorter the time period. At a temperature of 52 deg C (126 deg F ), the pH of 12 must be maintained for 72 hours. At 70 deg C (158 deg F), the p H of 12 must only be maintained for 30 or more minutes. The alkaline stabilized product is suitable for application in landscapi ng, agricultural and/or mine reclamation. The residuals act as a lime substitute, source of organic matter and specialty fertilizer. The alkaline stabilization facilities are suitable for use with liquid or dewatered wastewater solids. Alkaline stabilization has several advantages including the following: 1. Consistency with EPA's national beneficial reuse policy; 2. Simple technology, requiring few special skills for reliable operation; 3. Easy to construct; 4. Small land area required; 5. Flexible operation; and, 6. Help to create soil pH conditions in which metals are insoluble, minimizing plant uptake and movement of metals to groundwater. Possible disadvantages include the following: 1. The resulting product is not suitable for use with all soil types. 2. The volume of material i n increased by approximately 15 to 50 percent in comparison to other stabilization techniques, such as digestion. 3. There is the potential for odor generation. 4. There is the potential for dust production. 5. There is the potential for pathogen regrowth if the pH drops below 9.5 while the material is stored prior to use. 6. The nitrogen content in the final product is lower than that in several other biosolids products. Nitrogen is converted to ammonia, which is lost to the atmosphere or to the headworks of the treatment works. Plant available phosphorus can be reduced through the formation of calcium phosphate. 7. There may be fees associated with proprietary processes. When designing an alkaline stabilization facility, items to be considered include the following: 1. Percent solids of infeed wastewater solids 2. Desired results (Class A or Class B), which affect the amount of alkaline material needed and mixing time 3. Source and volume of alkaline material 4. Odor control equipment at the processing facility Technical Memorandum No. 2 5-2 Okeechobee Utility Authority Residuals Management July 2004 C] 5. Storage and curing area s Equipment required to produce a Class A product may include the following: 1. Wastewater solids feed system 2. Lime Storage 3. Lime transfer conveyor 4. Mixer 5. Air emission control equipment to m inimize odors and dust 6. Supplemental heat source Figure 5-1 illustrates a typical alkaline stabilization operation. Odors associated with alkaline stabilized products are dependent upon the characteristics of the wastewater solids. In facilities where the sludge age in the wastewater treatment process is minimized, the odors at the residuals processing facility and the end use site are likewise minimized. The dryer the cake, the less I ime required and the easier the mater ial is to process. Maintenance on an alkaline stabi lization system is no more complicated than that required for the wastewater treatment plant; however, some of the equ ipment may require higher maintenance due to the caustic nature of the alkaline materials. Two of the selected systems use alkaline stabilization as follows: BIOSET SYSTEM The Bioset system consists mainly of a pressure reactor where dewatered sludge is mixed with lime (to increase the pH to or above 12) and sulfamic acid pow der (to increase the temperature to 70 deg C (158 deg F)) and where the mixture is provided with suffi cient reaction time under a controlled pressure. Figure 5-2 illustrates the process, while Figure 5- 3 illustrates the site specific system. The residuals thicken to approximately twice the inlet solids, i.e., dewatered residuals from a centrifuge enters the reactor at approximately 20 percent solids; residuals at 40 percent solids is discharged from the reactor. Technical Memorandum No. 2 5-3 Okeechobee Utility Authority Residuals Management July 2004 STORAGE SILO LIME ALKALINE ADDITIVE RESIDUALS MIXING 'TREATED AIR VENTED TO ATMOSPHERE PROCESS AIR SUPPLEMENTAL HEAT SOURCE OR ALKALINE MIXING TO ACHIEVE CLASS A ......................�...................... PRODUCT DISTRIBUTION PRODUCT CURING AND STORAGE ' FIGURE 5-1: TYPICAL ALKALINE TREATMENT FOR DOMESTIC RESIDUALS METZGER & WILLARD, INC. Civil • Environmentol Engineers 6600 Kidd- River Perk—y, Suite 550 To po, FlaWo 33637 (817) 977-6005 • 0 POLYMER STORAGE POLYMER MAKEDOWN SYSTEM 290 CF/DAY ® 20% FROM DIGESTER 1 GPM (11 CY/DAY) - 54,000 GPD ® CENTRIFUGE 0.8% IN -LINE ROTARY LOBE z a z GRINDER PUMP o w On 0> Q Z [1 a U'1 O O 00 w O O LIME SILO SULFAMIC Ln I ACID FEED 53,600 GPD TO HEADWORKS BIO SET REACTOR 333 CF/DAY ® 20% It ® 40% (6.2 CY/DAY) 2 - 40 CY ROLL -OFF CONTAINERS FOR STORAGE VENTED FREE TO ATMOSPHERE AMMONIA SCRUBBER STABILIZED MATERIAL TO DISTRIBUTION - 2 - 40 CY CONTAINERS REMOVED FROM SITE 0 FIGURE 5-2: BIOSET SYSTEM METZGER & WILLARD, INC. Civil • Environmental Engineers Tompa, Florida 33637 (813) 977-6005 1 I I I (EXIST. TREATMENT PLANT I TT _ _ _ _ _ r _ I M I I I I I I I o O i— vrun1r % V / y a u I:n 60 d NAIL TA. 10+00 J G. i 6+00 f Je 1U f ' 30 J• 0 75 50 . 1� ^ •fir 7.2 5 AGRICULTURAL FILTER SCALE. 1 "=50' CLARIFIER 1A FIGURE 5-3: SITE SCHEMATIC- BIOSET SYSTEM METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, Florida 33637 (813) 977-6005 Nitrogen in the residuals reacts to f orm ammonia which kills the pathogens in the residuals. The ammonia is released at the end of the reactor, captured in an air scrubbing system at a concentration of less than one percent. The scrubbed air is released to atmosphere. Dewatered, stabilized residuals are stored in a roll -off container until hauled for reuse or disposal. Lime is stored in a 35-foot tall silo and is automatically fed to the mixer. Lime is used at a rate of 16 percent of sludge by mas s or 0.187 tons per hour (7.5 tons per week). Sulfamic acid is fed through a metering conveyor that rem oves the powder directly from the hopper. The acid is fed at a rate of 0.16 percent of sludge by mass or 0.0019 ton s per hour (0.075 tons per week). Sulfamic acid is stable and in crystalline form. TABLE 5-2. FLOWRATE INFORMATION — BIOSET SYSTEM Centrifuae Parameters Input Solids Content 0.8 % Output Solids Content 19.5 % Estimated Polymer Feed Rate 1 gpm Operation Schedule 8 hours/day — 5 days/week Ultimate Volumetric Flowrate at Input Solids Content 54,000 gpd Bioset Parameters Input Solids Content 19.5 % Output Solids Content 40.0 % Estimated Lime Feed Rate 16% of sludge by mass Estimated Sulfamic Acid Feed Rate 0.16% of sludge by mass Flowrate Calculations Mass Flowrate (dry solids) = 3638 #/day = 1.82 ton/day (54,000 gpd) (0.8/100)(cf/7.48 gallons)(63#/cf) Mass Flowrate (at 19.5%) = 2332 #/hr = 1.17 tons/hour (3638 #/day)(1 00/19.5)(1 day/8 hours) Mass Flowrate (w/lime and acid) = 2709 #/hour = 1.36 tons/hour (2332 #/hr)(1 + 0.16 + 0.0016) Mass Flowrate (at 40%) = 10,600 #/day = 5.3 tons/day (2709 #/hr)(19.5/40.0)(8 hr/day) Volumetric Flowrate (w/lime and acid) = 5.20 gpm (2709 #/hour)(cf/65#)(7.48 gal/cf)(1 hr/60 min) Based upon the above flow information, the probable construction cost for a BioSet system is approximately $1.76 Million with an annual operating cost of approximately $63,000 per year, excluding disposal costs. Appendix A provides a breakdown of the opinion of probable construction and operating costs. Technical Memorandum No. 2 5-7 Okeechobee Utility Authority Residuals Management July 2004 FKC SYSTEM — CLASS A The FKC System consists mainly of a screw press where de watered residuals that have been mixed with lime are reduced to approximately 25% solids. Steam is introduced into the system to raise the temperature as required to kill the pathogens in the residuals. Figure 5-4 illustrates the FKC system. Basically, lime is added to the residuals in the lime addition tank to raise the Ph to 12 for vector attraction re duction. The Ph adjusted residuals are pumped to a flocculation tank where it is mixed with a high Ph suitable polymer to aid in dewatering. The residuals then enter the rotary screen thickener where it is thickened to approximately 5% solids, and then it falls into the hopper of the screw press, where dewatering and pasteurizati on occurs. The rotary screen thickener is capable of handling large amounts of liquid residuals. A fuel oil -powered boiler system produces steam which heats the center of the screw press. The steam does not di rectly contact the residuals. The condensate is re -cycled through the system. A site schematic for the FKC System is provided in Figure 5-5. The dewatered and pasteurized residual s fall from the screw press onto a conveyor t o a container where they are stored until disposal. Odors are removed from the residuals during the screw press process and enter the pressate and are taken back to the headworks of the treatment facility. Lime is stored in two tall silos next to the lime mixi ng tanks. Lime is fed at a rate of 500 pounds per ton of dry solids or 0.019 Tons/Hour (3.2 Tons/Week). TABLE 5-3. FLOW RATE INFORMATION — FKC SYSTEM — CLASS A Rotary Screen Thickener Parameters Input Solids Content 0.8 % Output Solids Content 5% Estimated Polymer Feed Rate 1 gpm Estimated Lime Feed Rate 500 #/Dry Ton of Solids Operation Schedule (for 2 MGD) Ultimate Volumetric Flowrate at Input Solids Content Screw Press Parameters Input Solids Content Output Solids Content 25% of sludge by mass 8 hours/day — 7 days/week 54,000 gpd 5% 25% Technical Memorandum No. 2 5-8 Okeechobee Utility Authority Residuals Management July 2004 26' 0 14' SWD L1tINDUCTOR FREEBOARD OLI.ELIMECONVEYOR 1 500 LBS./TON BIOSOLIDS 0.45 TONS/DAY ILul o000 2NoaR' 54,000 GPD0.8% �<yll SOLIDS 1.8 TONS/DAYRECIRCULATIONPUMPS a (100 GPM) 109 5 n. v''i a LIME LIME SILO 2 CONVEYOR 2 INDUCTOR ANK 2 26' 0 14' SWD 2' FREEBOARD LIME/SLUDGE MIXING TANKS o: zz POLYMER STORAGE CONNECTION TO WATER SYSTEM POLYMER MAKEDOWN SYSTEM ROTARY SCREEN P1 =1 GPM THICKENER R3 0 5% 5 CFM SLUDGE FEED \2010 DRY LBS./HR PUMPS (38 GPM) Q (L � a FLOCCULATION vi n TANK (285 GAL.) z ¢ CONNECTION TO WATER SYSTEM CONNECTION BOILER SYSTEM �- TO WATER SYSTEM ST1 % IST, SCREW PRESS R` 257 HR�o 0 CF/DAY (52 CY/DAY) 200 DRY LBS./HR ) CONVEYOR TO STORAGE & DISPOSAL N 2-40 CY ROLL -OFF CONTAINERS w u «a: 0. 0 53=36.4 GPM TO ON -SITE PUMP STATION & HEAD WORKS FIGURE 5-4: FKC SYSTEM -CLASS A METZGER &WILLARD,INC. Civil • Environmental Engineers Tamp., F1.6d. 33637 (613) 977-6005 lb x L— — — — — - — — - 0 :EXISTTREATMENT I + 7 . ENT PONT I CLARIFIER to CLARIFIER 18 LIME;! SIL011 :2 — PROPOSED PIPING 37.4 WAS PUMP STATION 1XII N �p TOATION FILTERS TANKS 11 DIGESTER IA EXISTING 4" RWM EXISTING ABOVE GROUND FUEL TANK TO BE RELOCATED 00 PROPOSED ACCESS DRIVEWAY —PAVED 50'X70' COVERED AREA • i7KC SYSTEM 34- - FIGURE 5-5: FKC RESIDUALS MANAGEMENT SYSTEM —CLASS A SITE SCHEMATIC 50 0 25 so 100 METZGER &WILLARD, INC. SCALE: 1"=50' C - Environmental Engineers livilp.. FI�Ido 33637 (813) 977-6005 0 Mass Flowrate (dry solids) _ (54,000 gpd) (0.8/100)(cf/7.48 gallons)(63#/cf) Mass Flowrate (at 5%) _ (3638 #/day)(1 00/5)(1 day/8 hours) Mass Flowrate (w/lime) _ (9095 #/hr)(1 + 0.25) Mass Flowrate (at 25%) _ (11,369 #/hr)(5/25)(8 hr/day) Volumetric Flowrate (w/lime) _ (11,369 #/hour)(cf/65#)(7.48 gal/cf)(1 hr/60 min) 3638 #/day = 1.82 ton/day 9095 #/hr = 4.55 tons/hour 11,369 #/hour = 5.68 tons/hour 18,200 #/day = 9.1 tons/day 21.8 gpm Based upon the above, the opinion of probable construction cost for the com plete FKC system is $3.1 Million, with an annual operating cost of $61,70 0, excluding disposal costs. Appendix A provides a breakdown of the costs. In April 2004, FKC set up a truck -mounted pilot unit at the Authority's WWTP to demonstrate the system, to verify the performance of the unit and to allow Authority personnel to observe and assess the benefits of the technology for the Authority's use as a residuals management system. A copy of a letter summarizing the pilot demonstration and resu Its is provided in Appendix B. Authority personnel were pleased with the system and the ease of operation. Eight separate test runs were performed and the results indicate that the FKC screw press is capable of producing Class A or Class B residuals with the aerobically digested sludge. For Class A residuals, outlet residuals will be approximately 25 — 30 percent solids. For Class B residuals, outlet residuals will be approximately 18 percent solids. The demonstration study shows that screw speed is critical to the operation — the lower the speed of the screw, the dryer the cake/the higher the speed, the higher th a capacity of the system. The study also showed the necessity for the Rotary Screen Thickener to allow for a more efficient use of the screw press by removing "free water" prior to the press. In addition, lime dosages were confirmed to be in the range of 400 — 600 pounds per dry ton of residuals. The demonstration study provided mix ed results for polymer dosages. FKC recommends that a polymer supplier advise on the appropriate polymer. Technical Memorandum No. 2 5-11 Okeechobee Utility Authority Residuals Management July 2004 • • The demonstration project was performed on digested sludge, not raw waste activated sludge. FKC SYSTEM — CLASS B As an alternative to the FKC System — Class A, the installation of the system can be installed in phases. Phase I would include the installation of the rotary screen thickener and polymer system, the screw press, pumps, and sludge conveyor. The lime thickening system and boiler system is installed as a part of Phase 11. By breaking the system into two phases, the initial costs are reduced; however, the final product is Class B and is subject to limits on disposal. To upgrade to Class A at a later date, the lime thickening system, lime silos, boiler system, etc., will require construction and/or installation. TABLE 5-4. FLOW RATE INFORMATION — FKC SYSTEM — CLASS B Rotary Screen Thickener Parameters Input Solids Content 0.8 % Output Solids Content 5 % Estimated Polymer Feed Rate 1 gpm Estimated Lime Feed Rate N/A Operation Schedule 8 hours/day — 7 days/week Ultimate Volumetric Flowrate at Input Solids Content 54,000 gpd Screw Press Parameters Input Solids Content 5 % Output Solids Content 18 % Flowrate Calculations Mass Flowrate (dry solids) = 3638 #/day = 1.82 ton/day (54,000 gpd) (0.8/100)(cf/7.48 gallons)(63#/cf) Mass Flowrate (at 5%) = 9096 #/hr = 4.55 tons/hour (3638 #/day)(1 00/5)(1 day/8 hours) Mass Flowrate (at 18%) = 20,213 #/day = 10.1 tons/day (20,213 #/hr)(5/18)(8 hrs/day) Volumetric Flowrate (w/lime) = 38.8 gpm (20,213 #/hour)(cf/65#)(7.48 gal/cf)(1 hr/60 min) Based upon the above, the opinion of probable construction costs and annual operat ing costs are as follows: TABLE 5-5. CLASS B. PHASE I I I TOTAL BREAKDOWN OF COSTS FOR PHASES I AND 11 FOR FKC SYSTEM — CONSTRUCTION COST $ 1.74 Million $ 2.28 Million $ 4.02 Million ANNUAL OPERATING COST $16,400 $61,700 Technical Memorandum No. 2 5-12 Okeechobee Utility Authority Residuals Management July 2004 Compostinq Process The USEPA defines composting as the "biological degradation of organic materials under controlled aerobic conditions. The process is used to stabilize wastewater solids prior to their use as a soil amendment or mulch in landscaping, horticulture and agriculture." By composting, pathogens are destroyed in the wastewater residuals, as well as, odors are minimized, and vector attraction potential is reduced. The composting process is required to maintain a temperature of at least 55 deg C (131 deg F) for at least thre a days to destroy pathogens. While methods of composting vary; generally, the science is the same. The residuals are thickened or dewatered and placed in the composting area — in a windrow, an aerated static pile or a specially -constructed vessel. Some methods require the introduction of a bulking agent — usu ally yard wastes. As the material composts, microorganisms break d own organic matter into carbon dioxide, water, heat and compost. Oxygen on a consistent basis is required to maintain the composting rate. The major advantages of composting include the following: 1. Production of a reusable product; 2. Use of the product returns valuable nutrients to the soils; 3. Compost is easily handled —when compared to other processes; and, 4. Compost is not subject to end use restrictions. The major disadvantages include the following: 1. Composting may increase the amount of material produced (1 cy of cake is equivalent to 3 cy of compost); 2. Potential for fires — however, sufficient aeration and moisture will reduce the potential for fires. In addition, proper design of the facilities will likewise reduce this potential. 3. Land requirements for windrow and static piles. Environmental impacts to air and water are also reduced through proper design of th e system. PARKSON CORPORATION THERMO-SYSTEM SOLAR SLUDGE DRYING The Thermo -System consists mainly of large, greenhouse -like solar drying facilities. Liquid or thickened residuals are introduced into the solar chambers. A small mobile tiller, Technical Memorandum No. 2 5-13 Okeechobee Utility Authority Residuals Management July 2004 resembling a state fair "bumper car" and called a "mole", travels though the residuals mix ing and aerating, which allows the residuals to dry and prevents odor s. The mole is capable of orienting itself in the drying chamber by using ultrasonic sensors and tills the material under its carriage to prevent splashing. The unit can also be operated by remote control. The unit does not compact the material. A microprocessor monitors atmospheric conditions, and controls the ventilation system, louvers, and the til ler operations. The microprocessor adjusts the ventilation system to allow for optimization of the incoming solar ra diation. The materials produced are between 75 percent and 90 percent solids. Thi s product resembles either a dry palletized material or a fin er dirt -like material. A typical thermo-system is illustrated in Figure 5-6 and is based upon thickened residuals. For thickened residuals, the solar chambers do not require an underdrain system. For liquid sludges, the facilities should include underdrains. No chemicals are required for a composting system. Polymer is required for thickening prior to composting if a centrifuge or belt press is used. Operator attention is required for placing the material in the solar chambers and removing the compost material at the end of the drying cycle, approximately 27 days. Operator attention during the compost proced ure is limited. The material is removed by use of a front-end loader and placed in a roll-o ff container for disposal. The material is placed in the solar chambers by piping (liquid residuals) or front-end loader (thickened materials). A site schematic for the Thermo -System with centrifuge is shown in Figure 5-7. The Thermo -System with drum thickener is shown in F igure 5-8. Technical Memorandum No. 2 5-14 Okeechobee Utility Authority Residuals Management July 2004 POLYMER STORAGE TO WATER SYSTEM POLYMER MAKEDOWN SYSTEM 290 CF/DAY O 20% P -1 GPM (11 CY/DAY) CENTRIFUGE TER FROM DIG:ZPO - 54,00O 0.8% IN -LINE GRINDER ROTARY LOBE PUMP 5 CY FRONT END c LOADER a Qv S 52,000 GPD TO HEADWORKS �^ t COMPOSTING FACILITIES 2 - 42' X 204' SOLAR DRYING FACILITIES - (27 DAY DETENTION TIME EACH) 11 CY DAY O 20% INFLUENT 79.5 CY O 75% REMOVED AFTER 27 DAYS (2.8 CY/DAY) SLUDGE MIXER - FILL SOLAR FACILITY 1 FOR 27 DAYS. FILL SOLAR FACILITY 2 FOR 27 DAYS. REMOVE SOUDS FROM SF1 AND BEING FILLING SF1 FOR 27 DAYS. REMOVE SOLIDS FROM SF2. REPEAT CYCLE COMPOSTED MATERIAL TO DISTRIBUTION 79.5 CY O 75% EVERY 27 DAYS - AFTFR C.pMPgSTING (2.9 CY/DAY) 5 CY FRONT END 2 - 40 CY ROLL -OFF CONTAINERS LOADER FOR STORAGE • FIGURE 5-6: THERMO SYSTEM WITH CENTRIFUGE METZGER & WILLARD, INC. Civil • Environmental Engineers T—P., Fl.,id. 33637 (813) 977-6005 L3 6 r FILTERS 4" RCWM TO BE RELOCATED 1c] at EXISTING ABOVE GROUND n.STORAGE o FUEL TANK TO BE RELOCATED 50'X50' COVERED AREA ROPOD A CESS DRIVEWAY -PAVED.'['[ ... . . . . . . . . . . ?6 :R Ll60 d NAIL 5TA. 10+00 1111413.16+00 -14 + Jg 10 CEN',rI i!`UGE (DEWAiTERING 1 I, I, EXISTING EXISTING DIGESTER 1A DIGESTER 1B 37.0 -3+ -34 37-- COMPOST FACILITY A COMPOST FACILITY 8 IPA ., • PROPOSED ACCESS DRIVEWAY —STABILIZED 50 0 25 50 100 SCALE: 1"=50' FIGURE 5-7: THERMO SYSTEM MATH CENTRIFUGE SITE SCHEMATIC METZGER &WILLARD, INC. Civil - Environmental Engineers Tampa, Florida 33637 (813) 977-6005 EXISTING LINED HOLDING POND RUM OTARY, D R E­ T14CKENES I NG Me. DEWAtRING ha 1 i II w. VFILTERS 4" RCWM TO BE )OSTING, DIGESTER "UST' RELOCATED 1A DIGESTER B EXISTING ABOVE GROUND STc IRAGE FUEL TANK TO BE RELOCATED 50=1 + COVERED AREA ,'" A fEWAy— k D: . ...... E.STNQ 1.0.11 EXISTING LINED 111b cr- HOLDING NO MT. 60 d NAIL ',STA. I0+00 LINED RIGATION PUMP STATION ANG. 16+00 —14e 0. CL FIGURE 5-8: THERMO—SYSTEM W/DRUM THICKENER PROPOSED ACCESS DRIVEWAY —STABILIZED 6SITE SCHEMATIC 0 0 30 60 120 METZGER &WILLARD, INC. SCALE. 1"=60' Civil - Environmental Engineers Tompo, Florida 33637 (813) 977-6005 TABLE 5-6. FLOW RATE INFORMATION — THERMO-SYSTEM WITH CENTRIFUGE. Centrifuge Parameters Input Solids Content 0.8 % Output Solids Content 19.5 % Estimated Polymer Feed Rate 1 gpm Operation Schedule 8 hours/day — 5 days/week Ultimate Volumetric Flowrate at Input Solids Content 54,000 gpd Thermo-Svstem Parameters Input Solids Content 19.5 % Output Solids Content 75 % Required Drying Surface 1904 sy No. of Chambers 2 Width, each 42 ft Length, each 204 ft Drying time per cycle 27 No. of Drying Cycles per chamber 12.5 per year Flowrate Calculations Mass Flowrate (dry solids) = 3638 #/day = 1.82 ton/day (54,000 gpd) (0.8/100)(cf/7.48 gallons)(63#/cf) Mass Flowrate (at 19.5%) = 2332 #/hr = 1.52 tons/hour (3638 #/day)(100/19.5)(1day/8 hours) Mass Flowrate (at 75%) = 4,900 #/day = 2.42 tons/day (2332 #/hr)(19.5/75)(8 hr/day) Volumetric Flowrate = 4.45 gpm (2332 #/hour)(cf/65#)(7.48 gal/cf)(1 hr/60 min) TABLE 5-7. FLOW RATE INFORMATION — THERMO-SYSTEM WITH ROTARY DRUM THICKENER. Drum Thickener Parameters Input Solids Content 0.8 % Output Solids Content 6.5 % Operation Schedule 8 hours/day — 5 days/week Ultimate Volumetric Flowrate at Input Solids Content 54,000 gpd Thermo-Svstem Parameters Input Solids Content 6.5 % Output Solids Content 75 % Required Drying Surface 5713 sy No. of Chambers 6 Width, each 42 ft Length, each 204 ft Drying time per cycle 27 days No. of Drying Cycles per Chamber 12.8 per year Flowrate Calculations Mass Flowrate (dry solids) = 3638 #/day = 1.82 ton/day (54,000 gpd) (0.8/100)(cf/7.48 gallons)(63#/cf) Mass Flowrate (at 6.5%) = 7,000 #/hr = 3.50 tons/hour (3638 #/day)(100/6.5)(1day/8 hours) Mass Flowrate (at 75%) = 4,900 #/day = 2.43 tons/day (7000 #/hr)(6.5/75)(8 hr/day) Volumetric Flowrate = 4.45 gpm (2332 #/hour)(cf/65#)(7.48 gal/cf)(1 hr/60 min) Technical Memorandum No. 2 5-18 Okeechobee Utility Authority Residuals Management July 2004 Based upon the above, the opinion of probable construction cost for the complete Thermo - System using a drum thickener is approximately $3.78 Million, with an annual operat ing cost of approximately $25,000. F or the Thermo -System usi ng the centrifuge, the opinion of probable construction cost is approx imately $1.9 Million, with an annual operating cost of approximately $17,000, excluding disposal costs. Appendix A provides a breakdown of the costs. Evaluation of Processes The above processes were evaluated based upon the following criteria: 1. Capital Costs 2. Operation and Maintenance C osts 3. Odors 4. Public Acceptance 5. Volume Reduction 6. Marketing and Reuse Potential of the Final Product 7. Risk Factors 8. Complexity of Operation 9. Storage of the Final Product The Capital Costs of the process is extremely important to a small utility such as the Authority. Capital costs are assigned a maximum criteria weight of 10. O & M Costs are a continuing cost to the Authority and represents a significant annual investment. O&M Costs are likewise assigned the maximum weight of 10. Odors are a significant concern for the Authority. The WWTP is placed within a 407 acre site, but this site is adjacent to a residential treatment facility (Eckerd Youth Foundation) and is close to a single family home subdivision. Due to the facility location, the odor criteria is weighted at 8. The Public Acceptance criterion includes health, odor issues, truck traffic and dust. Most of the methods evaluated meet the EP A Part 503 requirements for a Class A residual; therefore, the material and process should pose no impact on the public's health. The Class B process is trucked to the landfill. Technical Memorandum No. 2 5-19 Okeechobee Utility Authority Residuals Management July 2004 0 .7 Odor was considered in the preceding criterion; however, the public's perception of odors (real or imaginary) may depend upon relations with t he public during the construction and operation of the facility. Truck traffic during construction is important, as well as, traffic associated with transport and delivery of chemicals, off -site -generated residuals, and hauling of the final product. This criterion is weighted at 5. Volume Reduction affects materials handling and storage requirements. The volume of material to be handled affects the labor and equip ment necessary to transfer, store and haul material. This criterion is weighted at 5. The Marketing and Reuse Potential of the End Product criterion applies to the ability of the Authority to find a market for the ultimate product — to either be removed at no charge to the Authority or for a minimal fee. It is not anticipated that the Authority will be able to sel I the product for an offset of operating costs. However, the marketability (quality) of the product affects the ability to have the product hauled away for benefici al purposes. This is a major criterion and is weighted at 10. The Risk Factor criterion considers worker's health, safety and attitude toward their job. Chemical type and handling procedures, fire and explosion potential are also consider ed. This criterion is weighted at 3. The Complexitv of Operation of the process is important in determining the level of operator training, repair and maintenance schedules. Since the processes evaluated are all capable of being operated by any competent operator, this criterion is weighted at 3. The Storage of the Final Product is important as it considers the ease of storage, space required, odors emitted, moisture content and eq uipment required for handling the final product. This criterion is weighted at 3. Table 5-8 provides the evaluation matrix for the p rocesses studied. Technical Memorandum No. 2 5-20 Okeechobee Utility Authority Residuals Management July 2004 TABLE 5-8. EVALUATION M, EVALUATION CRITERIA WEIGHT* 1. Capital Costs 10 2. O&M Costs 10 3. Odors 8 4. Public Acceptance 5 5. Volume Reduction 5 6. Marketing and Reuse Potential 10 7. Risk Factors 3 B. Complexity of Operation 3 9. Storage of Final Product 3 TOTAL SCORE 570 PERCENTAGE OF MAXIMUM*** Capital Costs, Phase I Annual Costs, Phase I Capital Costs, Phase II Annual Costs, Phase II TOTAL CAPITAL COSTS * 1 is the least important 10 is the most important ATRIX FOR P BIOSET SCORE** TOTAL 8 80 5 50 8 64 5 25 5 25 8 80 5 15 5 15 8 24 378 66.32 $ 1,764,800 $ 62,700 $ 1,764,800 1 ROCESSES FKC S' CLASS A SCORE TOTAL 5 50 10 100 8 64 5 25 4 20 8 80 5 15 5 15 5 15 384 67.37 'STEM PARKSON CORP. CLASS B DRUM THICKENER SCORE TOTAL SCORE TOTAL 10 100 1 10 10 100 8 80 4 32 10 80 3 15 8 40 4 20 10 50 1 10 10 100 4 12 5 15 8 24 5 15 3 9 10 30 322 420 56.49 73.68 $ 3,081,800 $ $ 61,700 $ $ 2,344,600 $ ** 1 is the least favorable 10 is the most favorable 1,740,900 16,400 2,280,800 61,700 4,021,700 *** $ 3,781,400 $ 25,000 $ 3,781,400 100 is the maximum sc THERMO-SYSTEM CENTRIFUGE SCORE TOTAL 6 60 10 100 10 80 8 40 10 50 10 100 8 24 10 30 10 30 514 90.18 ore 1,901,000 16,900 1,901,000 r� • Matrix Evaluation For each of the nine criteria used to evaluate the residual s processes, the following summary is provided. 1. Capital Costs: Figure 5-9 illustrates the variance in the capital costs for the selected processes. The lowest capital cost option is the FKC System — Class B. The highest capital cost option is the Thermo -System with a drum thickener (6.5% solids). The FKC System — Class B system is upgradable to a Class A system at a future date; however, the disposal opti ons for the Class B system are limited for the final product. Some land spreading at an approved site may be appropriate, but it is anticipated that the final product will be placed into landfill. The BioSet option has the second lowest capital cost of the Class A options. 2. Annual Costs: Figure 5-10 illustrates the variance in the annual costs for the processes. The lowest annual cost is found wi th the FKC System — Class B unit. However, when the unit is upgraded to Class A, the annual operating cost will increase. The highest annual cost is with the BioSet System. 3. Odors: Each of the Class A systems are fairly consistent in the removal of odors. The BioSet system provides a separate scrubber for the removal of the ammonia odors. The FKC System provides a rinse system in the rotary screen thickener and in the screw press. With both of these options, the amm onia odor is rinsed out of the air and sent back to the head of the treatment works. The Thermo -System has a low odor since the composting materials are turned and maintained at appropriate moisture levels to prevent odors from forming. The FKC — Class B system provides no treatment, only thickening for transportation to a landfill. Odors are possible with this system. Technical Memorandum No. 2 5-22 Okeechobee Utility Authority Residuals Management July 2004 FIGURE 5-9. PROCESS CAPITAL COSTS $4,000,000 $3,500,000 FKC -CLA $3,000,000 $2,500,000 $2,000,000 $1,500,000 $1,000,000 $500,000 FKC - CL B Thermo - 6.5% • r -7 LJ $70,000 $60,000 $50,000 N �6 o $40,000 0 V! O 0 $30,000 Q $20,000 $10,000 FIGURE 5-10. ANNUAL COST COMPARISON BioSet FKC - CL A FKC - CL B Thermo - 6.5% 0 4. Public Acceptance: Public acceptance is a difficult criterion to gage. The public acceptance criterion varies from 3 for a Class B residual — which has no marketable value to an 8 for a composted material that can be used without restrictio ns on the location. Generally, the public is not interested in the actual treatment process; however, they are concerned with odors, noise, and inconvenience. For all of the processes except the Class B system, odors will be minimal. The noise levels will be similar for all processes. The Thermo -System resembles a plant nursery from the property line. Inconvenience to the public is judged based upon truck traffic to and from the site. The BioSet system requires lime, polymer and acid delivery. The FKC System — Class A requires lime, polymer and fuel oil delivery. The FKC System — Class B requires polymer delivery only. The Thermo -System requires polymer delivery only. All of the processes require the final product to b e removed from site; however, the more percent solids, the fewer trucks required to remove the product. 5. Volume Reduction: Each of the processes reduces the percent solids in the residuals. On a daily basis, the Thermo -System process reduces the final product handling to 2.4 tons/day. T he BioSet System reduces the final product volume to 5.3 tons/day. The FKC System — Class A reduces the final product volume to 9.1 tons/day. The FKC System — Class B reduces the final product volume to 10.1 tons/day. For handling, the Thermo -System with drum thickener requires more handling between the thickener an d the composting system. The Thermo -System with centrifuge requires minimal interim handling. The FKC System operates 7 days per week, while the other systems operate only 5 days/week. Figure 5-11 illustrates the volume of residuals produced for each of the selected processes. 6. Marketing and Reuse Potential: The FKC System — Class B system has no marketing or reuse potential. The BioSet and FKC System — Class A materials are useful as a soil enhancer and may have a market to a bulk customer. The composted material from the Thermo -System is easily handled and packaged for Technical Memorandum No. 2 5-25 Okeechobee Utility Authority Residuals Management July 2004 FIGURE 5-11. QUANTITY OF RESIDUALS PRODUCED DAILY 12 FKC - CL B 10 • • 7 f3 reuse and sale. It is anticipated that the final product will be provided to a bulk customer for reuse and resale, rather than the Authority performing this function. Risk Factors: Class A residuals are processed to reduce the vector attraction and to reduce the risk from pathogens. The FKC System — Class B has not been processed, only dewatered; therefore, this system has a potential risk to the safety and health of the operations staff. The operations staff is aware of these potential risks since the existing system is also Class B; no problems have been reported. The other processes considered include pathogen removal and vector attraction reduction. The operator's attitude is usuall y directly proportional to the amount of maintenance required on a piece of equipment. The FKC System — Class A has the most "moving parts". The Thermo -System has the fewest "moving parts", but requires operator activity to place the thickened residuals in the solar chambers. Complexity of Operation: The FKC System and the BioSet System require minimal operator attention after the system is activated. The Thermo -System requires the operators to place the residuals in the solar chambers; however, after placement, the Thermo -System performs all the activity by itself until the residuals are composted to the final product. The drum thickener and the rotary screen thickener are fairly comparable in operations complexity. The BioSet reactor requires no operations input other than temperature monitoring. The F KC System screw press requires operation and maintenance attention. The "moles" in the T hermo-System require maintenance. The operation and maintenance requirements for centrifuges have improved considerably in the last 5 years or so. Maintenance require ments should be no more complex than for a rotary screen thickener or a drum thickener. The product produced is more easily processed. Technical Memorandum No. 2 5-27 Okeechobee Utility Authority Residuals Management July 2004 Belt filter presses were not considered in this analysis due to the operations staff aversion to the proces s due to the odors and maintenance re quired to operate a belt filter press. 9. Storage of Final Product: Storage of the final product is assumed to be in 40 cy roll - off containers. The containers are removed from the site on an intermittent basi s. The following table summarizes the requirem ents for containers and removal. TABLE 5-9. STORAGE REQUIREMENTS FOR FINAL PRODUCT NUMBER OF REMOVAL DESCRIPTION CONTAINERS FREQUENCY 1. BioSet System 2 7 days 2. FKC System — Class A 2 5 days 3. FKC System — Class B 2 5 days 4. Thermo -System 2 27 days The FKC System — Class B material is likely to have more odors and attr act vectors than the other processes and received the lowest "score" in the matrix. Additional information on the processes selected is provided in Appendix C. Technical Memorandum No. 2 5-28 Okeechobee Utility Authority Residuals Management July 2004 SECTION 6. SELECTED PROGRAM FOR RESIDUALS MANAGEMENT Meetings were held with Authority staff to discuss residuals management options and to develop a program for implementation. B ased upon many factors including capital costs, operating costs, potential market development, and operator satisfaction with equipment, the following program was determined to meet the needs of the Authority for this expansion of the process. The installation of the FKC System — Class B will meet the immediate needs of the Authority. At some future date, a bulk market may be developed to receive residuals from the area, and at that time, the Class B system will be upgraded to Class A. The Class B residuals will be transported to the landfill for disposal. By dewatering the residuals, the cost of disposal of the residuals decreases considerably as shown in the following Table 6-1. For a tipping cost of $35/ton of material and a trip cost of approximately $5/ton of material, tipping costs are reduced by approximately $850,000 per year. The capital cost associated with the F KC System — Class B is $1,741,000. The system would pay for itself in less than three years, when comparing hauling "thickened" residuals to "dewatered" residuals. Technical Memorandum No. 2 6-1 Okeechobee Utility Authority Residuals Management July 2004 TABLE 6-1. DISPOSAL CC ALTERNATIVE Liquid Residuals, No Thickening* Capital Cost = $0 Liquid Residuals, Thickened Capital Cost = $50,000 Class A Dewatered Capital Cost = $3,081,800 Class B Dewatered Capital Cost = $1,741,000 * Okeechobee County Landfil is not c ,STS FOR LIQUID AND DEWATERED RESIDUALS. WARM MONTHS COLD MONTHS TIPPING TIPPING QUANTITY, COST, NUMBER OF QUANTITY COST, NUMBER OF VOLUME TONS/DAY $/YEAR TRIPS/DAY VOLUME TON/DAY $/YEAR TRIPS/DAY 50,000GPD 208.5 $ 1,301,040 9 100,000GPD 417 $ 2,602,080 17 12,500 GPD 52.1 $ 325,104 3 25,000 GPD 104.3 $ 650,832 5 52 CY 9.1 $ 56,784 3 80 CY 10.1 $ 63,024 5 irrently equipped to receive liquid residuals. 52 CY 9.1 $ 56,784 80 CY 10.1 $ 63,024 3 5 TIPPING COST, TOTAL FOR YEAR $ 3,903,120 $ 975,936 $ 113,568 $ 126,048 • • • • APPENDIX A 0 BUDGET ESTIMATE Bioset Residuals Management System 22-Apr-04 1. Equipment - Installation - Assume 50% 2. Concrete Slab, Building 3. Electrical, General 4. Centrifuge, Polymer System Installation - Assume 50% 5. In Line Grinder, Installed 6. Rotary Lobe Pump, Installed 7. Acid Feed System, Installed 8. Ammonia Scrubber, Installled 9. Storage Containers SUBTOTAL Contingency, 30% TOTAL Annual Operating Costs, $NR Okeechobee Utility Authority WWTP Expansion MWI: 11333.04 Page 1 of 10 Pages 400,000 200,000 = 600,000 150,000 50,000 335,000 167,500 = 502,500 20,000 = 25,000 INCLUDED INCLUDED = 10,000 1,357,500 407,300 1,764,800 = 62,700 7/16/2004 Bio-Set System • 0 BUDGET ESTIMATE FKC Residuals Management System 9-Jul-04 1. Equipment (Lime Silos, Recirculation Pumps, Sludge Feed Pumps, Polymer System, Rotary Screen Thickener, Boiler System, Screw Press, RST Support, Conveyor) Installation - Assume 50% 2. Concrete for Steel Tanks, 60 CY @ $350/CY 3. Bldg, Slab, Cover and Walls 4. Storage Containers 5. Site Work, 5% 6. Electrical, 12% 7. Yard Piping, 15% 8. Mobilization, 10% SUBTOTAL Contingency, 30% TOTAL Annual Operating Costs, $/YR Okeechobee Utility Authority WWTP Expansion MWI: 11333.04 Page 2 of 10 Pages 1,278,150 639,075 1,917,225 21,000 140,000 10,000 104,411 263,116 368,363 282,412 2,370,637 711,200 3,081,837 61,700 7/16/2004 FKC Class A • BUDGET ESTIMATE FKC Residuals Management System - CLASS B 9-J u I-04 PHASEI 1. Equipment (Sludge Feed Pumps, Polymer System, Rotary Screen Thickener, Screw Press, RST Support, Conveyor) Installation - Assume 50% 2. Concrete for Steel Tanks 3. Bldg, Slab, Cover and Walls 4. Storage Containers 5. Site Work, 5% 6. Electrical, 12% 7. Yard Piping, 15% 8. Mobilization, 10% SUBTOTAL Contingency, 30% TOTAL Annual Operating Costs, $/YR PHASEII 1. Equipment (Lime silos, tanks, recirculation pumps, boiler system, etc.) Assume 5 year lag with 2.5% inflation per year (650,000 X 1.025b) Installation - Assume 50% 2. Concrete for Steel Tanks 3. Site Work 4. Electrical, 12% 5. Yard Piping, 15% 6. Mobilization, 10% SUBTOTAL Contingency, 30% TOTAL Annual Operating Costs, $/YR Okeechobee Utility Authority WWTP Expansion MWI: 11333.04 Page 3 of 10 Pages 528,700 264,350 793,050 140,000 10,000 47,153 = 113,166 = 141,458 94,305 1,339,132 401,739 = 1,740,870 16,400 811,550 405,775 1,217,325 21,000 148,599 = 208,039 159,496 1,754,459 526,300 2,280,759 61,700 7/16/2004 FKC Class B 0 • BUDGET ESTIMATE Thermo -System Residuals Management Facilities 22-Apr-04 Thermo -System with Drum Thickener - Requires 6 Solar Facilities 1. Equipment - Chambers (frames, walls, ends, doors, moles, ventilators, climatic sensors, control panels, etc.) Installation - Assume 75% 2. Concrete Slab and 3' Tall Walls (sides only) 3. Electrical, General 4. Drum Thickener, Polymer System Installation - Assume 50% 5. In Line Grinder, Installed 6. Rotary Lobe Pump, Installed 7. Front End Loader, Used 8. Piping 9. Storage Containers SUBTOTAL Contingency, 30% TOTAL Annual Operating Costs, $NR 1,375,000 1,031,250 2,406,250 INCLUDED INCLUDED 275,000 137,500 412,500 = 20,000 25,000 30,000 10,000 5,000 2,908,750 872,600 3,781,350 25,000 Okeechobee Utility Authority WWTP Expansion 7/16/2004 MWI: 11333.04 Page 4 of 10 Pages Thermo -System 6.5% - Drum Thick 11 U BUDGET ESTIMATE Thermo -System Residuals Management Facilities 22-Apr-04 Thermo -System with Centrifuge - Requires 2 Solar Chambers 1. Equipment - Chambers (frames, walls, ends, doors, moles, ventilators, climatic sensors, control panels, etc.) Installation - Assume 75% 2. Concrete Slab and 3' Tall Walls (sides only) 733 CY @ $350.00/CY 3. Electrical, General 4. Centrifuge, Polymer System Installation - Assume 50% 5. In Line Grinder, Installed 6. Rotary Lobe Pump, Installed 7. Front End Loader, Used 8. Piping 9. Storage Containers SUBTOTAL Contingency, 30% TOTAL Annual Operating Costs, $/YR 497,000 372,750 869,750 INCLUDED INCLUDED 335,000 167,500 502,500 = 20,000 = 25,000 30,000 = 10,000 5,000 = 1,462,250 = 438,700 1,900,950 16,900 Okeechobee Utility Authority WWTP Expansion 7/16/2004 MWI: 11333.04 Page 5 of 10 Pages Thermo -System 20% - Centrifuge • • BIO-SET System Operation Schedule: ANNUAL COSTS H R/DY 8 H R/W K 40 DY/WK 5 WK/YR 52.14 Electrical: Incidental 2 HP (EST) Centrifuge 75 HP Pumps 30 HP Lime Silo 5 HP Weigh Belt 5 HP 117 HP X 0.7458 KW/HP = 87.2586 KW Electrical Costs 87.2586 KW X 40 HR/WK X $ 0.06 /KW-HR = $ 209.42 M/K Chemicals: Lime Cost ($105/TN) 786.24 Acid Cost ($760/TN) 56.91 Polymer Cost (EST) 150.00 Electrical Cost ($0.06/KW-H R) 209.42 TOTAL OPERATION COSTS = $ 1,202.57 /WEEK ANNUAL COSTS = $ 62,702.03 /YEAR TM 2 - Residuals 7/16/2004 Okeechobee Utility Authority Page 6 of 10 Pages MWI: 11333.04 FKC System - CLASS A Operation Schedule: H R/DY 8 H R/W K 56 DY/WK 7 WK/YR 52.14 Electrical: Screw Press 3 HP RST 3 HP Agitator 1 HP Mixers X 2 10 HP Boiler 5 HP (EST) Valves X 4 2 HP (EST) Sludge Pumps 15 HP Sludge Recirc 20 HP (EST) Lime Silos X 2 10 HP Incidentals 2 HP (EST) 71 HP X 0.7458 KW/HP = 52.9518 KW Electrical Costs 52.9518 KW X 56 HR/WK X $ 0.06 /KW-HR = $ 177.92 /WK Chemicals: Lime Cost (EST) 756.00 Polymer Cost (EST) 250.00 Electrical Cost ($0.06/KW-HR) 177.92 TOTAL OPERATION COSTS = $ 1,183.92 IWEEK ANNUAL COSTS = $61,729.49 NEAR TM 2 - Residuals 7/16/2004 Okeechobee Utility Authority Page 7 of 10 Pages MWI: 11333.04 FKC System - CLASS B Operation Schedule. H R/DY 8 H R/W K 56 DY/WK 7 WK/YR 52.14 Electrical: Screw Press 3 HP RST 3 HP Agitator 1 HP Mixers X 2 0 HP Boiler 0 HP (EST) Valves X 4 2 HP (EST) Sludge Pumps 15 HP Sludge Recirc 0 HP (EST) Lime Silos X 2 0 HP Incidentals 2 HP (EST) 26 HP X 0.7458 KW/HP = 19.3908 KW Electrical Costs 19.3908 KW X 56 HR/WK X $ 0.06 /KW-HR _ $ 65.15 /WK Chemicals: Lime Cost (EST) 0.00 Polymer Cost (EST) 250.00 Electrical Cost ($0.06/KW-HR) 65.15 TOTAL OPERATION COSTS = $ 315.15 /WEEK ANNUAL COSTS = $16,432.08 /YEAR TM 2 - Residuals 7/16/2004 Okeechobee Utility Authority Page 8 of 10 Pages MWI: 11333.04 Thermo -System 6.5% w/Drum Thickener Operation Schedule: H R/DY 8 H R/W K 40 DY/WK 5 WK/YR 52.14 Electrical: Grinder 3 HP Pumps 7.5 HP Drum Thickener 50 HP (EST) Mole X 6 30 HP (EST) Incidentals 10 HP (EST) 100.5 HP X 0.7458 KW/HP = 74.9529 KW Electrical Costs 74.9529 KW X 40 HR/WK X $ 0.06 /KW-HR = $ 179.89 /WK Chemicals: Polymer Cost (EST) 300.00 Electrical Cost ($0.06/KW-HR) 179.89 TOTAL OPERATION COSTS = $ 479.89 /WEEK ANNUAL COSTS = $ 25,021.31 NEAR TM 2 - Residuals 7/16/2004 Okeechobee Utility Authority Page 9 of 10 Pages MWI: 11333.04 Thermo -System 20% w/Centrifuge Operation Schedule: H R/DY 8 H R/WK 40 DY/WK 5 WKIYR 52.14 Electrical: Grinder 3 HP Pumps 7.5 HP Centrifuge 75 HP Mole X 2 10 HP (EST) Incidentals 2 HP (EST) 97.5 HP X 0.7458 KWiHP = 72.7155 KW Electrical Costs 72.7155 KW X 40 HRNWK X $ 0.06 /KW-HR _ $ 174.52 /WK Chemicals: Polymer Cost (EST) 150.00 Electrical Cost ($0.06/KW-HR) 174.52 TOTAL OPERATION COSTS = $ 324.52 MEEK ANNUAL COSTS = $16,920.33 NEAR TM 2 - Residuals 7/16/2004 Okeechobee Utility Authority Page 10 of 10 Pages MWi: 11333.04 OKEECHOBEE UTILITY AUTHORITY TECHNICAL MEMORANDUM NO. 3 EFFLUENT DISPOSAL AND REUSE SYSTEM EXPANSION July 2004 METZ43ER & WILLARD, INC. Civil • Environmental Engineers 8600 HIDDEN RIVER PARKWAY SUITE 550 TAMPA, FL 33637 913-977-6005 TECHNICAL MEMORANDUM NO. 3 EFFLUENT DISPOSAL TABLE OF CONTENTS SECTION DESCRIPTION PAGE 1. INTRODUCTION 1-1 2. SUMMARY OF EXISTING TREATMENT 2-1 GENERAL 2-1 3. EXISTING REGULATIONS 3-1 STATE 3-2 4. CURRENT AND FUTURE FLOWS AND QUALITY 4-1 EXISTING QUANTITY 4-1 FUTURE QUANTITY 4-1 ANTICIPATED QUALITY 4-6 5. POTENTIAL DISPOSAL STRATEGIES 5-1 6. RECOMMENDED PROGRAM FOR EFFLUENT DISPOSAL 6-1 APPENDIX A Design Calculations B Opinion of Probable Construction C osts Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal TOC - 1 July 2004 • • LIST OF FIGURES NUMBER DESCRIPTION PAGE 2-1 Williamson Cattle Company Citrus Irrigation System 2-2 2-2 On -Site Spray Irrigation System 2-3 4-1 Projected Flows 4-5 5-1 Major Landowners in the Area 5-2 5-2 Hamrick & Sons, Inc., RIBs 5-4 5-3 Typical Deep Well Injection 5-6 5-4 Wetland Map of Florida 5-7 5-5 Typical Wetland Cross -Section 5-8 5-6 64.8 Acre Wetland 5-11 5-7 118.19 Acre Wetland 5-12 5-8 139.86 Acre Wetland 5-13 Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal TOC - 2 July 2004 LIST OF TABLES NUMBER DESCRIPTION PAGE 4-1 Historical Flows at the WWTP 4-2 4-2 Projected Flows 44 4-3 Characteristics of Flow and Strength of Waste 4-6 5-1 Allowable Loading Rates for a Man -Mad a Wetland Treatment System 5-9 5-2 Wetland Sizing (Acres) Based upon Allowable Loading Rates 5-g 5-3 Opinion of Costs for Man -Made Wetlands 5-10 Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal TOC - 3 July 2004 SECTION 1 INTRODUCTION As a part of the on -going expansion program for the Okeechobee Utility Authority (Authority) Wastewater Treatment Plant, this Technical Memorandum was developed to address the effluent disposal options. T his Memorandum is provided to support the efforts of Technical Memorandum No. 1 — Wastewater Treatment Plant Expansion, dated July 2004. The existing effluent disposal system will be discussed, flow projections for effluent needs, develop alternatives for disposal, develop associated costs with the alternatives and provide a recommendation for the effluent disposal program. It is anticipated that the Authority will continue to expand their collection system through infill in existing areas, sewerage to areas already developed and sewerage to new developments proposed through agreements with developers. Another effort the Authority is making is in the reduction of phosphorus into Lake Okeechobee by the removal of septi c tanks and small packaged wastewater treatment plants from areas adjacent to the Lake. T he WWTP expansion program includes providing service to these areas. Additional information for these efforts is provided in Technical Memorandum No. 1. Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 1 - 1 July 2004 SECTION 2 SUMMARY OF EXISTING TREATMENT General The existing WWTP treats the wastewater to an advanced secondary level with high- level disinfection. Aftertreatment, the effluent is stored in open -topped ponds until pumped to the reclaimed water user, Williamson Cattle Company or the on -site spray irrigation system. The ponds consist of a 2-acre lined pond, a 23-acre lined pond and a 17-acre unlined pond. A second 2-acre lined pond is used for water that is `rejected" fr om the reclaimed water system during monitoring of the effluent for high levels of turbidity and/or low chlorine residuals. The effluent is placed automatically into the "reject pond" and must be manually sent through the treatment process again. Good, clean reclaimed water is pumped from the ponds through an agricultural filter and sent to the citrus irrigation system of Williamson Cattle Company. The citrus system is permitted for 0.8 MGD of reclaimed water on an annual average basis. The citrus system is shown in Figure 2-1. In addition, the existing WW TP has a spray irrigation system, permitted for 0.3 MGD of reclaimed water use. The on -site sys tern is shown in Figure 2-2. Williamson Cattle Company has indicated that they are not currently in need of any additional reclaimed water. The on -site spray irrigation system is also at the m aximum level permittable for the site. Other alternatives for effluent disposal will be considered. Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 2-1 July 2004 -- 22 ECaEND POUNDAIM VOUTN DEVELOPMENT CENTER Riz. Jbt-- -- 29 I I O I Q� VVV32 TWP 36S. TWP 37S. LEGEND yi++..r NµOa[0 aN1A0Aa anDE am Nm C4slwq wsrtw�rzw LSlU1EwT gMNSAMN SK1S4 Op [wSlMa COMEa11O1 MI1lCa [bs. roTrxc w�rza wtu o, cmT PPgI.TwM uTca cu • FIGURE 2-1 ULLIAMSON CATTLE CO. REUSE SITES METZGER $ WILLARD, INC. Civil • Environmental Engineers Tompo, Florida 33637 (613) 977-6005 2',1" RED Y BALL VALVIE ED CDAT EWOSPPE SUPPORT Y—Yvi' PTT ALL y, REDI�RED A q SPRP114ER HEADS PER SPEORCATIONS ,EAg•R� -•••• 1' FULL CIRCLE IMPACT SPRINKLER, RAINBIRD MODEL R 70CSPH 5/i"x5/B" SD 2'v1' RED. a' . x' avoss (x' PLUD AT END DE ME) "pM Y BALL VALVE- 2' w �TSPRINKLER SPACING 120' x 120' PROPOSED SPRINIUR PIPING ISOMETRIC L-------- A S µ7g,5 • r-j • FIGURE 2-2 ON —SITE SPRAY IRRIGATION SYSTEM METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, Florldo 33637 (613) 977-6005 • • SECTION 3 EXISTING REGULATIONS State In addition to the rules governing the treatment pr ocess itself, the following rules are the main state regulations pertaining to effluent disposal. 1. 62-528 — Underaround Iniection C ontrol: • Provides the conditions and requirements for the use of an Underground Injection Well for disposal of effluent. • Defines the rules that govern the construction and operation of injection wells. • Serves the purpose of preventing the degradation of the quality of other aquifers adjacent to the injection zone. 2. 62-610 — Reuse of R eclaimed Water and Land Apoli cation: • Defines reuse as deliberate application of reclaimed water for a beneficial purpose. • Provides a comprehensive and detailed set of requirements for the design and operational criteria of a wide range of reuse and land application systems consistent with EPA's Guidelines for Water Reuse. 3. 62-611 — Wetlands ADDlication: • Provides state regulations and standards for domestic wastewater discharges to wetlands, both man-m ade and natural. • Establishes frequency and monitoring criteria of all treatment, receiving and man-made wetlands. Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 3-1 July 2004 • • SECTION 4 CURRENT AND FUTURE FLOWS AND QUALITY Existing Quantitv In September 1998, the existing plant was placed on-line. At that time, the older (1985) contact stabilization activated sludge (CSAS) facility was taken off-line for maintenance and repairs. Currently, the existing CSAS facility remains off-line. Historical flows at the existing WWTP are shown in Table 4-1 (October 1998 through June 2004). Future Quantity Projected flows were developed based upon system growth anticipated from infill, inclusion of existing package plants that are removed from service and collection system expansion. Growth is the area appears to be increasing as evidenced by developer agreement requests and the development of sewer systems for areas adjacent to the Lake. The system expansion schedule and projected flows are shown in Table 4-2 and illustrated in Figure 4-1. The WWTP was originally designed to be expanded in 1 MGD increments. Based upon the projected flows for 2004 — 2016, the Authority should consider a 2 MGD expansion at this time. As a part of this analysis, 2 MGD, 3 MGD and a 4 MGD alternatives are considered as shown in the following sections. From the projected flows, and based upon the existing wastewater treatment plant design, the characteristics presented below are being used in the development of the expanded facility. Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 4-1 July 2004 0 0 TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY MONTHLY 3-MONTH RUNNING ANNUAL 3 MONTH AVERAGE AS % DATE AVERAGE, MGD AVERAGE, MGD AVG, MGD DESIGN CAPACITY Oct-98 0.448 0.448 Nov-98 0.522 0.485 Dec-98 0.500 0.490 0.490 44.5 Jan-99 0.548 0.523 0.505 47.6 Feb-99 0.647 0.565 0.533 51.4 Mar-99 0.663 0.619 0.555 56.3 Apr-99 0.595 0.635 0.560 57.7 May-99 0.492 0.583 0.552 53.0 Jun-99 0.668 0.585 0.565 53.2 Jul-99 0.560 0.573 0.564 52.1 Aug-99 0.545 0.591 0.563 53.7 Sep-99 0.747 0.617 0.578 56.1 Oct-99 0.701 0.664 0.599 60.4 Nov-99 0.611 0.686 0.606 62.4 Dec-99 0.555 0.622 0.611 56.6 Jan-00 0.593 0.586 0.615 53.3 Feb-00 0.643 0.597 0.614 54.3 Mar-00 0.569 0.602 0.607 54.7 Apr-00 0.509 0.574 0.599 52.2 May-00 0.481 0.520 0.599 47.2 Jun-00 0.476 0.489 0.583 44.4 Jul-00 0.494 0.484 0.577 44.0 Aug-00 0.446 0.472 0.569 42.9 Sep-00 0.564 0.501 0.554 45.6 Oct-00 0.546 0.519 0.541 47.2 Nov-00 0.532 0.547 0.534 49.8 Dec-00 0.483 0.520 0.528 47.3 Jan-01 0.570 0.528 0.526 48.0 Feb-01 0.591 0.548 0.522 49.8 Mar-01 0.678 0.613 0.531 55.7 Apr-01 0.646 0.638 0.542 58.0 May-01 0.658 0.661 0.557 60.1 Jun-01 0.704 0.669 0.576 60.8 Jul-01 0.724 0.695 0.595 63.2 Aug-01 0.648 0.692 0.612 62.9 Sep-01 0.780 0.717 0.630 65.2 Oct-01 0.702 0.710 0.643 64.5 Nov-01 0.649 0.710 0.653 64.6 Dec-01 0.567 0.639 0.660 58.1 Table 4-1 7/16/2004 • 0 TABLE 4-1. OUA FLOW DATA - WASTEWATER TREATMENT FACILITY DATE Jan-02 Feb-02 Mar-02 Apr-02 May-02 Jun-02 Jul-02 Aug-02 Sep-02 Oct-02 Nov-02 Dec-02 Jan-03 Feb-03 Mar-03 Apr-03 May-03 Jun-03 Jul-03 Aug-03 Sep-03 Oct-03 Nov-03 Dec-03 Jan-04 Feb-04 Mar-04 Apr-04 May-04 Jun-04 MONTHLY AVERAGE,MGD 0.601 0.612 0.567 0.533 0.483 0.493 0.618 0.552 0.660 0.608 0.622 0.735 0.777 0.729 0.711 0.660 0.638 0.696 0.656 0.815 0.766 0.716 0.696 0.666 0.685 0.716 0.683 0.658 0.631 0.616 3-MONTH AVERAGE,MGD 0.606 0.593 0.593 0.571 0.528 0.503 0.531 0.554 0.610 0.607 0.630 0.655 0.711 0.747 0.739 0.700 0.670 0.665 0.663 0.722 0.746 0.766 0.726 0.693 0.682 0.689 0.695 0.686 0.657 0.635 RUNNING ANNUAL AVG, MGD 0.662 0.664 0.655 0.645 0.631 0.613 0.604 0.596 0.586 0.579 0.576 0.590 0.605 0.615 0.627 0.637 0.650 0.667 0.670 0.692 0.701 0.710 0.716 0.711 0.703 0.702 0.699 0.699 0.699 0.692 3 MONTH AVERAGE AS % DESIGN CAPACITY 55.1 53.9 53.9 51.9 48.0 45.7 48.3 50.4 55.5 55.2 57.3 59.5 64.7 67.9 67.2 63.6 60.9 60.4 60.3 65.7 67.8 69.6 66.0 63.0 62.0 62.6 63.2 62.3 59.8 57.7 Table 4-1 7/16/2004 TABLE 4-2. PROJECTED FLOWS FOR OUA WWTP (2003-2016) Jul-04 ,.v�O;k y;r :p:K,' .�'' "§'" :"v'iCY'�f.s�Y''.'A'S:•f>,Su :. P>3+ 5:,' .ti,Yy, y.D,. pile tErid.A.f;Year 1,, 2012 2013 2014 2015 2016 Taylor Creek Isles 122,500 122,500 Ousley Infill 10,000 10,000 10,000 10,000 Treasure Island 112,000 223,000 50,000 SW (160 units) 30,000 10,000 SE (1000 units) NE (300 units) 25,000 37,500 50,000 62,500 50,000 25,000 25,000 50,000 Misc Projects Other Growth 19,150 25,000 22,691 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 25,000 27,696 33,563 43,040 47,491 51,116 54,269 56,875 58,922 61,020 63,171 65,375 TOTAL for YEAR, GPD1 141,650 200,191 234,696 379,063 178,040 144,991 126,116 104,269 81,875 83,922 86,020 88,171 90,375 AVERAGE DAY, GPC 766,000 907,650 1,107,841 1,342,537 1,721,601 1,899,641 2,044,632 2,170,748 2,275,016 2,356,892 2,440,814 2,526,834 2,615,005 2,705,380 MAXIMUM DAY, GP 1,149,000 1,406,858 1,717,154 2,080,933 2,668,481 2,944,443 3,169,179 3,364,659 3,526,275 3,653,182 3,783,262 3,916,593 4,053,258 4,193,339 • 7/16/2004 FIGURE 4-1. PROJECTED WASTEWATER FLOWS, 2003 - 2016 3,000,000 2,500,000 9� o a c� 1,500,000 O IU. 1.000,000 500,000 0 ! o OO 00 N cr) N N N N N N N N N N NO END OF YEAR v O N • Anticipated Qualitv It is anticipated that the quality of the influent waste stream at the OUA wastewater treatment facility will remain fairly consistent, provided no new industries develop in the area that could impact the quality of the waste. Table 4-3 summarizes the anticipated quality. TABLE 4-3. CHARACTERISTICS OF FLOW AND STRENGTH OF WASTE. FLOW CHARACTERISTICS 1 DESIGN Peak Daily Flow I PDF MGD 4.00 Maximum Monthly Flow j MMF , MGD 3.00 J Annual Average Daily Flow I AADF 1 MGD 2.00 f Minimum Flow I MF 1 MGD 0.80 ) Peak Hourly Flow I PHF I MGD I 4.00 INFLUENT AND EFFLUENT CHARACTERISTICS I INFLUENT EFFLUENT Carbonaceous Biochemical Oxygen Demand CBOD5 mg/L j 300 < 10 Total Suspended Solids I TSS mg/L 1 250 I < 10 1 Total Nitrogen I TN ' mg/L 1 40 I < 3 1 1 Total Phosphorus I TP 1 mg/L 1 10 I < 2 1 Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 4-6 July 2004 SECTION 5 POTENTIAL DISPOSAL STRATEGIES Effluent disposal capacity is critical to the expansion of the wastewater treatment facilities. Possible sites in the area of the WWTP were evaluated using soils maps and aerial photographs, as well as the proximity to the WWTP site. Previous hydrogeological data from the initial expansion progra m were used to develop estimates for reuse capacities on sites. Discussions with potential customers and regulatory agencies have also been held throughout the planning process. Reuse water is required to be treated to a high level (public access quality) so that the water can be used for all types of landscape, crop, golf course, sod or pasture irrigation. The use of reclaimed water in Florida by individual homeowne rs for lawn and landscaping irrigation is common in areas where potable water shortages limit the amount of irrigation water available. The majority of the development in the Okeechobee area is far from the plant and adjacent to the La ke, which is approximately 5 miles away. Figure 5-1 illustrates the major property owners in the vicinity of the WWTP. Many of these sites have been reviewed during the expans ion process. Recent discussions have been held with the Eckerd Youth Development Center, Hamrick & Sons, Inc., and Williamson Cattle Company. Previous discussions (prior to 1998) have been held with the then owners of Grassy Island Ranch, the C ounty for use of the Cemetery and the Airport, and the Department of Corrections for u se of reclaimed water at the prison site. The quantity of flow that could be taken to the E ckerd site is negligible, so serious consideration has not been given to this site at this time. Grassy Island Ranch is now owned by SFWMD and is being used for a demonstration project of man-made wetlands treatment of surface water. The Cemetery use would also be negligible. The Airport and the corrections sites are not economically feasible due to the costs of transport to the sites. For this study, the following alternatives were evaluated. Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 5-1 July 2004 • - M- O • n. r r r • �' t_Y t t :aa?r�t'le•I `�� �� L t■I��t_ r M ,,� ',s '�{t'- Sil �. y�-'F �j : 1 � 7 ,, r � �•� :�.�1,fI �, • iimnl�3y� :0C�11I11 1...•v' aF...�.11! 1`..� �tr .,. 11 t tj ��':',..l,k..—•��Ii1.`^l��l��i.........r r,.•.r, 1�tyLy�i1� as • 1. Williamson Cattle Company —Additional Citrus Irrigation 2. Hamrick & Sons, Inc. — Rapid Infiltration Basins (RIBs) 3. WWTP Site — Underground Injection Well 4. WWTP Site — Man-made Wetlands Opinions of probable construction costs for each of the viable alternatives were developed and sketches of these alternatives are provided herein. Williamson Cattle Comganv — Citrus Irriciation The citrus site is currently receiving approximately 0.4 MGD annual average daily flow (permitted for 0.8 MGD) for irrigation of citrus over 760 acres of land. The system is shown in Figure 2-1. The total property is approximately 8600 acres, mostly used as ranchland for cattle grazing. Williamson Cattle Company (WCC) has rights of first refusal on the reclaimed water produced at the Autho rity facility; however, WCC has indicated that they are at maximum capacity for application at this time. Further evaluation was not performed. Hamrick & Sons, Inc. — RIBs The Hamrick property contains primarily Immok alee and Myakka fine sands, but doe s have substantial areas of Pomello fine sand. The use of some or all of the Pomello fine sand areas for RIBs was discussed. Approximately 130 acres were identified for use for the ponds, as shown i n Figure 5-2. Previous soils analyses were performed at the site i n 1995 during the previous expansion program. Based upon this work and a loading rate of 0.5 gpd/sf, it has been determined that the site m ay be able to handle approximately 0.44 MGD of effluent disposal. In addition, the I and (130 acres) would require a lease and/or purchase agreement. The opinion of construction cost for the improvements at the H amrick site was determined to be approximately $1,620,000. In addition, the cost for the land is as follows: $32,400/year to lease or $2,600,000 to purchase the 130 acre site. Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 5-3 July 2004 ECKERD YOUTH DEVELOPMENT CENTER HRS- WWTP SITE 1 � n V 2,400 LF OF 10" P. V. C. II II II 11 11 11 II II II II 11 II it II II II 11 II II 11 II II II II II II II It II II 1 1 1 1 I I I I I I I II II 11 II II II II II II II II II 11 II 11 II II 11 II 11 II II II II II II II I II II 11 II it it II II II 11 II II II II II II II II II II II II II II II II II II II II II II It II It 11 11 11 i WILLIAMSON CATTLE CO. HAMRICK & SONS OF 8" P.V.C. 0 0 FIGURE S-2 HAMRICK & SONS, INC. PROPOSED RIBS METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, F1011da 33637 (613) 977-6005 WWTP Site - Underground Iniection Well The cost for an underground injection well includes the drilling, testing, permitting and inspection of the well. The main advantage of th a deep well is the ability to use the well in wet or dry weather. The main disadvantages are that the water placed in the well is not retrievable for use by agricultural interests and the costs of the well. The capacity of the well is determined after the construction of an exploratory well and the testing program is completed. Wells that have been developed in the area have shown a high capacity and it is assumed that a well of the WWTP site would be rated in the millions of gallons. A typical injection well is shown in Figure 5-3. The costs for the development of the deep wells range from $2 Million to $5 Milli on, based upon review of data available. Si nce the quality of the effluent is very high, pretreatment is unlikely and the opinion of cos t for the development of the well is $3 Million. The on -site spray irrigation system would remain in service. WWTP Site — Man-made Wetlands Man-made wetlands are becoming a common method of effluent disposal in Florida. Figure 5-4 shows a map provided by FDEP illustrating the wetlands in use for wastewater treatment in the State. T he wetland system is very simple to operate — clean, effluent is discharged into the head of the wetlands through a spreader system. The water flows through the system, with a minimum travel time of 14 days, and out the discharge structure to the existing perimeter ditch. From the perimeter ditch, the water would flow to Taylor Creek directly, with possibly a portion sent through an existing natural wetland to rehydrate that area and prevent degradation. The system requires monitoring to prevent harm to the wetland plants and surface waters where the wetland discharges. A typical cross-section of a wetland is shown in Figure 5-5. Fish are provided to avoid excessive mosquito populations. Plants are chosen for their ability to reduce nutrients in the effluent. The final di scharge would meet the requirements of the FDEP for introduction into Taylor Creek. Wetlands are sized based upon the nutrient levels introduced into them, as well as hydraulic considerations. Allowable loading rates are as follows: Technical Memorandum No. 3 Okeechobee Util ity Authority Effluent Disposal System 5-5 July 2004 0 Potable Water 1 Casing 1500 Cement 2500 Open Hole n - SURFICIAL AQUIFER -_-_-_-_-_-_ CONFINING ZONE x , , UPPER FLORIDAN AQUIFER y CONFINING LAYER ''. POSSIBLE PERMEABLE Il l I I' II I 'I l i i LAYER I I I I I I I I I I I I I I I I I I I I I I I I I I I I I l l l l l l l l i I I I l l l l CONFINING LAYER I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I ! I I I I I I � V i ------- FIGURE ' , FIGURE 5-3 TYPICAL UNDERGROUND INJECTION ZONE INJECTION WELL METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, Florida 33637 (813) 977-6005 0 �=� .t � Map Of� ,; WasftwoUr Wetlanlift In Flwida Revised 4M/02 A I Bayou Marcus 22 Northwood 2 Rice Creek 93 Door Park Wotlimdo 3 St. John's County SA16 224 Petra Trookstop 6 Spencer 4 Blacks Ford 26 ftoo WaUand 6 "urlburt Field 27 Lakeland, Glendale 0 Apalachicola 98 Ft. Meade 7 Soot Wetland 29 Glades County IE 8 Jasper 30 Port of the, wands South 9 Monticello 31 Orange County Northwest 21 10 009SA 32 ugh Springs Commercla-1 park 11 Orlando tav-teriy Wetlaticis 12 Slue Heron 13 Yulse 14 South Central Regional 16 Yankee Lalcts, Seminole 16 Hilliard 17' Waldo Wetlands 10 Emist0antral no&nial It Indian River 20 Lessbwq 21 Wokodahatchoo Wetland Color Key Natural Wetlaids Mart -made Wetlands Combination of N aturall and Man-made FIGURE 5-4 WETLAND MAP METZGER &WILLARD, INC. Civil - Environmental Engineers Tampa, Florida 33637 (813) 977-6005 EMERGENT PLANTS \\/\ \/7 6 INLET flll� i FLOATING PLANTS OPEN WATER INLET/OUTLET ►'\`\►I. y' l'l- �jj �ij OUTLET SUBMERGED PLANTS STRUCTURE FIGURE 5-5 PROPOSED WETLAND CROSS SECTION METZGER & WILLARD, INC. Civil • Environmental Engineers Tampa, Florida 33637 (813) 977-6005 L] TABLE 5-1. ALLOWABLE LOADING RATES FOR A MAN-MADE WETLAND TREATMENT SYSTEM. PARAMETER LOADING RATE Hydraulic Loading Rate 6"/week Total Nitrogen 75 g/m2-yr Total Phosphorus 9 g/m2-yr Currently, the average phosphor us in the reclaimed water is approximately 2.8 mg/L, as P. In addition, the average nitrogen in the reclaimed water is approximately 7.7 mg/L, as N. The following analysis of wetland sizing includes the use of the average nutrient loadings, as well as, potential requirements from the FDEP permit as shown in the following table. TABLE 5-2. WETLAND SIZING (ACRES) BASED UPON ALLOWABLE LOADING RATES FLOW CONDITION HYDRAULIC PHOSPHORUS NITROGEN LOADING LOADING LOADING 1 MGD I TP = 2.8 mg/L 43 106 35 TN = 7.7 mg/L TP = 1.0 mg/L 43 38 14 TN = 3.0 mg/L 1.3 MGD ( TP = 2.8 mg/L 56 138 46 TN = 7.7 mg/L TP = 1.0 mg/L 56 49 18 TN = 3.0 mg/L 2 MGD I TP = 2.8 mg/L 86 213 70 TN = 7.7 mg/L TP = 1.0 mg/L 86 76 27 TN = 3.0 mg/L 2.3 MGD I TP = 2.8 mg/L 99 244 81 TN = 7.7 mg/L TP = 1.0 mg/L 99 87 31 TN=3.0mg/L 3 MGD I TP = 2.8 mg/L 129 319 105 TN = 7.7 mg/L i TP = 1.0 mg/L 129 114 41 TN = 3.0 mg/L 3.3 MGD I TP = 2.8 mg/L 142 351 116 TN = 7.7 mg/L TP = 1.0 mg/L 142 125 45 TN = 3.0 mg/L The limiting factors are as follows: 1. When the Phosphorus concentration is 2.8 mg/L in the i nfluent, the phosphorus loading rate is the factor that determines the wetland size. Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 5-9 July 2004 • • 2. When the Phosphorus concentration is 1.0 mg/L in the i nfluent, the hydraulic loading rate is the factor that determines the wetland size. Anticipated wetlands are illustrated in Figures 5-6, 5-7 and 5-8. The wetlands use the existing area between the WWTP and the perimeter ditch system. Figure 5-6 shows a 64.8 acre dual -cell wetland, which would be suitable for both the 1.0 MGD, 1.3 MGD and, possibly, 2.0 MGD flow ranges, with an influent phosphorus level of 1.0 mg/L. Figure 5-7 shows a 118.19 acre dual -cell wetland which would be suitable for 1.0 MGD at 2.8 mg/L of phosphorus and would also be suitable for flows up to 2.3 MGD with 1.0 mg/L of phosphorus. Figure 5-8 illustrates approximately a 140 acre dual -cell wetland system. This larger wetland is suitable for flows up to 1.3 MGD at 2.8 mg/L of phosphorus. This system is also suitable for flows over 3.0 MGD at 1.0 mg/L of phosphorus. For higher flows, larger wetlands would be necessary. There is approximately 270 acres available on the site for this use. It is anticipated that the on -site spray irrigation system would be eliminated due to the space requirements of the man-made wetland systems. An opinion of probable construction cost has been developed for the three wetland sizes described above. Appendix B provides a detailed breakdown of the cost estimate. TABLE 5-3. OPINION OF COSTS FOR MAN-MADE WETLANDS. DESCRIPTION OPINION OF COST 1. 64.8 acre Wetland $1,093,900 2. 118.19 acre Wetland $1,464,800 3. 139.86 acre Wetland $1,615,400 Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 5 - 10 July 2004 64.8 ACRE WETLANDS • 1.3 MGD EFFLUENT • PHOSPHORUS LOADING BASED UPON EFFLUENT CONCENTRATION OF 1.0 MGA OR • 1.0 MGD EFFLUENT • PHOSPHORUS LOADING BASED UPON EFFLUENT CONCENTRATION OF 1.0 MGA EMSMO lM•1NE0 HCUM POW 17 AA m \. (i \� WATER S1d1AM POND IL AC MIT STRLKTM jPROPOSED WETLAND 'A' 0 32.44 AC. 1 r.au Muw fT*J I uuul aut p� � STRUCTURE PROP 3Z 38 ACTkNO'B• no, ----'------'1----------- �- NP-6 mom w 3 - 1cr umw EAST 91a II I II I I II I I— 20• F•P L L EASEMENT -----------------7 ===_—Jul_----_..--�__._.___----�-----------=i— 0 FIGURE 5-6 64.8 ACRE ONSITE WETLANDS METZGER & WILLARD, INC. Civil • Environmental Engineers TBmpO. FIDFi00 33637 (813) 977-6005 118.19 ArRF WFTI ANQ5 • 1.0 MGD EFFLUENT • PHOSPHORUS LOADING BASED UPON EFFLUENT CONCENTRATION OF 2.8 MGA EM M9 IAAIMm HMDMG PM 17 AC 10 UILRY EAgWff 8 j rmucTm j PROPOSED WETLAND A' ® IY 35.89 AC I 0 IS PROPOSED WETLAND 45.79 AC. Ih �. U PROP D B :7! EASEMENT -- I -� �• T 1, ETW9ME EL X • • FIGURE 5-7 118.19 ACRE ONSITE WETLANDS METZGER SE WILLARD, INC. Civil • Environmental Engineers T9mp9. F1.11d9 33637 (813) 977-6005 739.86 ACRE WETLANDC_ ' / • 1.3 MGD EFFLUENT 1V WOM EAM3E11 i • PHOSPHORUS LOADING BASED UPON EFFLUENT CONCENTRATION OF 2.8 MGA !/ 0.0 0.0 f,f.. ®1.1 n III° if I U ut II trM 1m PROPOSED WETLAM�- II 39.07 AC. a >s U 0 PROPOSED WETLAND 'C" 62.75 AC.00 FIGURE 5-8 139.86 ACRE ONSITE WETLANDS METZGER 8f WILLARD, INC. Civil • Environmental Engineers Tampa, Florid. 33637 (B13) 977-6005 SECTION 6 RECOMMENDED PROGRAM FOR EFFLUENT DISPOSAL As a part of the development of this report, meetings were held with staff to review operations and capital cost concerns. In additi on, a meeting was held with representatives of the Florida Department of Environmental Protection to discuss permitting issues. As a result of these meetings and the recommended program for the expansion of the Wastewater Treatment Plant (Technical Memorandum No. 1), the following program for the expansion of the Effluent Disposal Facility is recommended. 1. Expand the effluent disposal facility to accommodate a minimum of 3.0 MGD with approximately 140 acres of on -site wetlands for a cost of approximately $1,615,400 and an influent phosphorus level of 1.0 mg/L. 2. Continue the operation of the Williamson Cattle Compan y Citrus Irrigation System with a capacity of 0.8 MGD. Technical Memorandum No. 3 Okeechobee Utility Authority Effluent Disposal System 6-1 July 2004 0 0 APPENDIX A • • APPENDIX A - WETLAND SIZING CALCULATIONS WETLAND SIZE, ACRES FLOW, HYDRAULIC PHOSPHORUS NITROGEN MGD TP, MG/L TN, MG/L I LOADING LOADING LOADING 1 2.8 7.7 43 106 35 1 3 43 38 14 1.3 2.8 7.7 56 138 46 1 3 56 49 18 2 2.8 7.7 86 213 70 1 3 86 76 27 2.3 2.8 7.7 99 244 81 1 3 99 87 31 3 2.8 7.7 129 319 105 1 3 129 114 41 3.3 2.8 7.7 142 351 116 1 3 142 125 45 4 2.8 7.7 172 425 140 1 3 172 152 55 Typical Calculations: Hydraulic Loading = 6"/week Land Req'd = Phosphorus Loading = Land Req'd = Nitrogen Loading = Land Req'd = 0.8571 "/day (Flow)(12"/ft) (0.8571"/day)(7.48 gallons/cf)(43,560 sf/ac) 9 g/m2-yr (TP)(Flow)(8.34 #/gal)(454 g/#)(365 d/yr)(3.281 ft/m)(3.281 ft/m) (9 g/m2-yr)(43,560 sf/ac) 75 g/mZ-yr (TN)(Flow)(8.34 #/gal)(454 g/#)(365 d/yr)(3.281 ft/m)(3.281 ft/m) (75 g/m2-yr)(43,560 sf/ac) APPENDIX B APPENDIX B - OPINION OF PROBABLE CONSTRUCTION COST FOR ON -SITE CONSTRUCTED WETLANDS 64.8 AC WETLAND -1.0 MGD and 1.3 MGD Earthwork 104,000 CY 4.07 423,280 Influent Structure 2 LS 15,000.00 30,000 Piping 1 LS 5,000.00 5,000 Discharge Structure 2 EA 15,000.00 30,000 Piping 1 LS 5,000.00 5,000 Gravel Bed 1 LS 7,500.00 7,500 Modifications to Perimeter Ditch Discharge Structure 1 LS 10,000.00 10,000 Landscaping Sod 20,000 SY 3.01 60,200 Emergent Plants 35 AC 2,000.00 70,000 Submerged Plants 29 AC 3,000.00 87,000 Floating Plants 35 AC 1,000.00 35,000 Fish, Mosquitofish 200 EA 10.00 2,000 SUBTOTAL 764,980 10% Mobilization 1 LS 76,498.00 76,498 SUBTOTAL 841,478 30% Contingency 1 LS 252,443.40 252,443 TOTAL 1,093,921 118.19 AC WETLAND -1.0 MGD Earthwork 170,000 CY 3.25 552,500 Influent Structure 3 LS 15,000.00 45,000 Piping 1 LS 12,000.00 12,000 Discharge Structure 3 EA 14,500.00 43,500 Piping 1 LS 7,500.00 7,500 Gravel Bed 1 LS 10,000.00 10,000 Modifications to Perimeter Ditch Discharge Structure 1 LS 10,000.00 10,000 Landscaping Sod 35,000 SY 2.50 87,500 Emergent Plants 60 AC 1,800.00 108,000 Submerged Plants 46 AC 2,900.00 133,400 Floating Plants 60 AC 825.00 49,500 Fish, Mosquitofish 350 EA 10.00 3,500 SUBTOTAL 1,062,400 10% Mobilization 1 LS 106,240.00 106,240 SUBTOTAL 1,168,640 30% Contingency 1 LS 296,200.00 296,200 TOTAL 1,464,840 139.86 AC WETLAND -1.3 MGD AND 3.0 MGD Earthwork 225,000 CY 2.75 618,750 Influent Structure 3 LS 15,000.00 45,000 Piping 1 LS 12,000.00 12,000 Discharge Structure 3 EA 14,500.00 43,500 Piping 1 LS 7,500.00 7,500 Gravel Bed 1 LS 10,000.00 10,000 Modifications to Perimeter Ditch Discharge Structure 1 LS 10,000.00 10,000 Landscaping Sod 45,000 SY 2.00 90,000 Emergent Plants 75 AC 1,500.00 112,500 Submerged Plants 63 AC 2,500.00 157,500 Floating Plants 75 AC 800.00 60,000 Fish, Mosquitofish 450 EA 10.00 4,500 SUBTOTAL 1,171,250 10% Mobilization 1 LS 117,125.00 117,125 SUBTOTAL 1,288,375 30% Contingency 1 LS 327,000.00 327,000 TOTAL 1,615,375