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HomeMy WebLinkAboutNC0063096_Meeting Notes_20030603NPDES DOCUHENT $CANNIN`: COVER SHEET NC0063096 Holly Springs WWTP NPDES Permit: Document Type: Permit Issuance Wasteload Allocation Authorization to Construct (AtC) Permit Modification Complete File - Historical Engineering Alternatives (EAA) Correspondence Owner Name Change r Meeting Notes Instream Assessment (67b) Speculative Limits Environmental Assessment (EA) Document Date: June 3, 2003 Thies document is printed on reizece paper - ignore any content on the re'rerne aide f , he __M4 G - / ►'� I f C ' PtOr.514, /7-• r /1C. Nct,olc 301"C 1. • �����C , 4 G/s f-" y4 &. 6. ,24 LCE . } i27 4/fGY'/I4 7►/45 may' Gj 19001 • t, 7/7 E A-11 T Uzi.' mot. r G cS1pnifr? $ •gal c c k rim1 ?l'7 /Gu,rz- 4°'6 `ice- t G- 41/ hewc ems' 4 ir) 6e4 % h-4. toil'7 /5 e'l /SCGYLr-- �9l ✓I S� /j� i l�G . % � q2 l,r inbri riu,e6 71e_. — /62.7 ev4i0 e)-; 7/06 . /10d--i--61(-471 4,1 2.9 /1169 • a 60 a 1t^flattZr j a " �� ancGr g s 'MC IT'fit l•ttPi; a c►�- �dl • G_' /E 1 v ��/ICI� / 7 AidD frfe4 - (A71/ °) • • I! y.113,4 �" t -w5 /IG p ink'. %' • Davis -Martin -Powell Holly Springs, NC Wastewater Planning Meeting June 3, 2003 Agenda / Discussion topics A. Introducctions B. Why we are here 1. NPDES Permit has been issued for 2.4 MGD Expansion 2. Town will prepare a 201 Amendment and apply for SRF funding of the next expansion 3. Town applied for a Clean Water Management Trust Fund Grant for reuse 4. Town's growth is continuing at a rapid pace 5. Town is concerned about "Flow Allocation Amounts" in the interim period C. Flow & Performance History 1. 2001/2002 History 2. Flows show a gradual increase in flows over the last 24 months 3. Performance of WWTP has been excellent during this period 4. Inflow/Infiltration — ongoing flow logging in the system, budgeted additional money for analysis and rehab next year. D. Proposed Plan 1. Re -rate the WWTP for 1.75 MGD (an additional 250,000 GPD) 2. Oxidation Ditch train would provide the bulk of increased capacity to equalize aeration times between trains 3. Planning / Design / Construction of the 2.4 MGD expansion will proceed accordingly 4. Effluent Filters and Disinfection will need upgrade when reuse is implemented 5. Town is participating in the West Wake County Regional planning effort for long-term P:IPROJ ECT\E32261Corr\DENR_mtg.doc HISTORICAL SUMMARY The review of the 2001-02 DMR's provided show that in general this facility is operating very well. The following average and peak parameters were observed: Parameter Flow BOD NH4 TSS Influent Effluent Average Peak Dav Average, Peak Day ----- ----- 0.76 MGD 2.308 MGD 306 mg/L 1560 mg/L 1.0 mg/L 18 mg/L 35 mg/L 55 mg/L 0.3 mg/L 10 mg/L 408 mg/L 2306 mg/L 1.5 mg/L 59 mg/L Despite the variations in influent BOD and TSS, percent removal of BOD, TSS, and ammonia have all averaged over 99%. The Town is pursuing the source of the high strength wastewater being discharged. PRELIMINARY DESIGN A few components will be operating above typical loading rates: o Effluent filters loading will be 2.3 gpm/SF; slightly above the typical 2.0 gpm/SF. This is within the general range of 2 - 6 gpm/SF, which may require more frequent backwashing. o The UV system will operate at 38 GPM per lamp at peak flow. Normal operation will be about 15 gpm/lamp. o The BOD loading on the aeration basins will be 22 lb/day/kft3 at a 300 mg/I influent design, slightly exceeding the 20 Ib/day/kft3 rate for conventional activated sludge. o Use of the PTU's second aeration basin for waste sludge storage must be discontinued, resulting in a loss in storage volume. Timely land disposal will be critical to performance. Preliminary Design Criteria Component Average, Anaerobic Zone 2.0 Oxidation Ditch Flow 1.375 Oxidation Ditch 20.0 PTU Aeration Flow 0.375 PTU Aeration 20.1 PTU Clarifiers #1, #2 347 Clarifier #3 357 Effluent Filters 2.28 Peak 0.80 347 1,039 5.70 Hours Detention MGD Hours Detention MGD Hours Detention Surface Loading, GPD/SF Surface Loading, GPD/SF Surface Loading, gpm/SF Town of Holly Springs 2.50 - 2.25 2.00 1.75 1.50 O • 1.25 5 1.00 - 0.75 0.50 0.25 0.00 C co Utley Creek WWTP Flow Summary —Avg Flow - Min Flow —�--Max Flow Flow Limit — — Flow Trend r •- �— .. �- N N N N N N N N N N N N M CO Cs, CO CO CD • - O O O O O O O CD O O O O O CDO O O O O O O O O O © fl c(3 �j Q) V O 4) co 4) - 0_ (B Q) U O a) ca U) CO 0. (13 LLQ < U) O Z 0 -3 � Q 2 < U) O Z 0 ) o_ Q Month Davis -Martin -Powell & Associates Town of Holly Springs 16.00 14.00 12.00 10.00 0 8.00 2 6.00 4.00 2.00 0.00 Utley Creek WWTP Effluent Ammonia ❑ Max Flow ■Avg NH4 ♦ Max NH4 ♦ ♦ ♦ ♦ ♦ ♦ 00 ■ n 1 . r N N N N N N N N N N N N M CO CO CO0,O O ss O O CIO O O O O O O O O O O O O O O O O O O O O O O O 0 N - N U O N (0 N (�0 O U O U) t6 Q) = Q Q U)0 Z O LL 2 Q Q cq 0 z 0 - u Q g Month Davis -Martin -Powell & Associates Town of Holly Springs 60.00 50.00 40.00 O O 30.00 2 20.00 10.00 0.00 Utley Creek WWTP BOD & TSS N 4 r, I. r t —L Avg BOD - II - Max BOD 1 ` , r t T Avg TSS - i - Max TSS • r , t 1 ' IF , r t t r r ' r —t— t ' t t r r r ' ■ r ' t I r , ' ' t ' t I !` r t , t t , y IN r 4 r ` t, , 1 r t r ' r -I t , • r �— r t- V- N N N CV N N N N N N CV CV (h COCr) CO CO O O 0 O C. O - O • - O O 0 O O O 0 O O O O O O 0 O CDCD CD 0 CD L i! (6 0- (O C. V 0 a) (CO Qom) (D 7 = n 0 U 0 N (a N N Q cp U Q 2-) -' < U) Z o-) tL 2 Q 2 Q CA Z 0 - LL < Month Davis -Martin -Powell & Associates 2.4 MGD Expansion Technical 201 Amendment CG&L Approval Final Design Review & Approval Bidding Construction dmp 1 holly-schedule.xls Town of Holly Springs 2.4 MGD WWTP Expansion I 1 11 T 1 I I 1 1 M U 0 O : U 0 O : U 0