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HomeMy WebLinkAboutNC0085359_Long Term Monitoring Plan_20191218 Public Works 4600 Goldmine Rd Monroe NC 28110 Union County T. 704-289-1434 www.unioncountync.gov EST. 1842 December 18, 2019 PECE VED Monti Hassan JAN 0 3 2020 PERCS Unit Pretreatment Coordinator NCDEQ/DWRIMPDES 1617 Mail Service Center Raleigh, NC 27699-1617 Subject: Approval of LTMP's & STMP; Union County Dear Mr. Hassan, In the interest in obtaining necessary data prior to requesting the full approval of Union County's Pretreatment Program; Union County would like to request approval of the attached LTMP's for Twelve Mile WRF & Crooked Creek LTMP along with the STMP for Grassy Branch WRF. The additional data required within these plans will allow for a clearer evaluation of our uncontrollable pollutant levels throughout our Collection System & Industrial baselines/contributions. The data collected will allow for more accurate calculations of our Headworks Analysis, and allocation tables. Please contact Katie Fleming 980-425-0735; kate.fleminq(c�unioncountvnc.gov , Union County Industrial Pretreatment Program Manager with any questions, concerns, or corrections. Thank you. Sincerely, (LA- Andrew Neff, PE Union County Public Works Water/Wastewater Division Director, Union County Public Works CC: Hyong Yi, UCPW Administrator Bart Farmer, WRF Superintendent Kate Fleming, Industrial Pretreatment Program Manager pN cat; m (i(Pfat Long Term Monitoring Plan RECEIVED JAN 03 2019 Union County Public Works NCDEQIDWRINPDES Twelve Mile Creek Water Reclamation Facility NC0085359 December 2019 Revision 1: Revision 2: Revision 3: • Union County Public Works Long Term Monitoring Plan—Twelve Mile Creek WRF A. Sampling Points(See Figure 1) 1. Influent(sample point 1): prior to mixing with recycle streams a. Regular composite sample collected for NPDES monitoring. 2. Effluent(sample point 2): after all treatment including chlorination a. Regular composite sample collected for NPDES monitoring 3. Activated Sludge Basin(sample point 3): a. Collect grab samples from mixed liquor influent and effluent distribution boxes 4. Sludge to Disposal(sample point 4): sample sludge going to final disposal a. Collect grab sample P 5. Significant Industrial Users(SIUs)per locations described in IUPs a. Collect grab samples at each industry 6. Uncontrollable: locations in collection system that serve residential and commercial development a. Collect grab samples at manhole#7214 at 2125 Roan Branch Road,downstream of only residential and commercial development. b. Collect grab samples at Mill Bridge Pump Station(MH-11060). c. Collect grab samples at Suburban Estates 1 (MH-5585). B. Pollutants of Concern(POCs) 1. NPDES permit requirements—biochemical oxygen demand(BOD),total suspended solids(TSS), ammonia(NI-I3-N),total Kjeldahl nitrogen(TKN),nitrite(NO2),nitrate(NO3),total phosphorus (TP). 2. Headworks analysis required—BOD,TSS,NH3-N, TKN,NO2,NO3,TP,nickel(Ni),copper(Cu), zinc(Zn), cadmium(Cd), chromium(Cr), cyanide(CN), lead(Pb),mercury(Hg), silver(Ag),and arsenic(As). 3. For land application 40 CFR 503 pollutants—As,Cd, Cr, Cu, Pb, Hg, Mo,Ni, Se,Zn, percent solids, and sludge to disposal flow. 4. SIU permitted pollutants required with the exception of the organics. 5. EPA required—Cd,Cr,Cu,Ni, Pb and Zn. 6. Additional SIU limited and/or monitored pollutants of concern—chloride,organics(EPA 624/625), pesticides(EPA 608),total oil and grease(HEM),total petroleum hydrocarbon(SGT-HEM), and chemical oxygen demand(COD). C. Detention Times Detention time is not taken into account in this program. The influent and effluent samples are taken on the same day and time for unpaired data for use in the headworks analysis. D. Flow Flow monitoring points are indicated on the attached map. Flow will be monitored during sampling events or calculated. Twelve Mile Creek LTMP Page 2 Union County Public Works Long Term Monitoring Plan—Twelve Mile Creek WRF E. SIU Monitoring Significant industrial user monitoring will be conducted per industrial use permits(IUP). The County will conduct once per year SIU sampling will be performed such that all SIUs are sampled for all LTMP POCs at least once per year. Twelve Mile Creek LTMP Page 3 Union County Public Works Long Term Monitoring Plan—Twelve Mile Creek WRF F. Sample Frequency and Plan Aeration Basin Sludge to Uncontrollable Pollutant of Influent(land Effluent(2) (3) Disposal (4) SIU(5) (6) Concern Year 1 Year 2,3,4 Year 5 Years 1-5 Years 1-5 Years 1-5 Years 1-5 Arsenic (As) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Cadmium (Cd) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Chromium(Cr) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Copper(Cu) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Lead(Pb) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Mercury(Hg) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Molybdenum(Mo) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Nickel(Ni) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Selenium(Se) 1/month Quarterly1/month 1/6 months Per 503 1/year � 1/6 months Silver(Ag) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Zinc(Zn) 1/month Quarterly 1/month 1/6 months Per 503 1/year 1/6 months Cyanide(Cn) 1/month 1/month 1/month 1/6 months ---- ---- 1/6 months Flow Continuous Continuous Continuous Continuous ---- ---- ---- BOD * Daily Daily Daily ---- ---- 1/year 1/6 months Weekly TSS * Daily Daily Daily Daily MLSS (% solids) ---- 1/6 months NH3-N * 1/month 1/month 1/month 1/6 months ---- 1/year 1/6 months Nitrate and nitrite 1/month Quarterly 1/month 1/6 months ---- 1/year ---- Nitrogen,total Weekly Weekly Weekly 1/6 months ---- 1/year ---- Phosphorus,total 1/month 1/month 1/month 1/6 months ---- 1/year ---- Twelve Mile Creek LIMP Page 4 Union County Public Works Long Term Monitoring Plan—Twelve Mile Creek WRF Aeration Basin Sludge to Uncontrollable Pollutant of Influent(1) and Effluent(2) (3) Disposal(4) SIU(5) (6) 1 Concern Year 1 Year 2,3,4 Year 5 Years 1-5 Years 1-5 Years 1-5 Years 1-5 Organics 1/6 months 1/6 months 1/6 months 1/6 months ---- ---- ---- Pesticides 1/6 months 1/6 months 1/6 months 1/6 months ---- ---- ---- Chloride 1/6 months 1/6 months 1/6 months ---- ---- ---- ---- Total oil and grease 1/year 1/year 1/year ---- ---- 1/year ---- (HEM) Total petroleum hydrocarbon 1/year 1/year 1/year ---- ---- 1/year ---- (SGT-HEM) Chemical oxygen 1/month quarterly 1/month ---- ---- 1/year demand(COD) Industry-specific ---- 1/year pollutants ! *Daily sampling excludes weekends and holidays Twelve Mile Creek LTMP Page 5 Union County Public Works Long Term Monitoring Plan—Twelve Mile Creek WRF G. Detection Level and Sample Method Practical Quantitation Limits Pollutant of Concern (PQLs), mg/L Sample Method Arsenic(As) 0.01 24 hr Composite Cadmium(Cd) 0.002 24 hr Composite Chromium(Cr) 0.005 24 hr Composite Copper(Cu) 0.005 24 hr Composite Lead(Pb) 0.01 24 hr Composite Mercury(Hg) 1.0 ng/L* (Method 1631) Grab* Molybdenum(Mo) 0.01 24 hr Composite Nickel(Ni) 0.01 24 hr Composite Selenium(Se) 0.01 24 hr Composite Zinc(Zn) 0.01 24 hr Composite Silver(Ag) 0.001 24 hr Composite Cyanide(Cn) 0.01 Grab BOD 2.0 24 hr Composite TSS 2.5 24 hr Composite NH3-N 0.1 24 hr Composite TKN 0.50 24 hr Composite Nitrate and nitrite 0.10 24 hr Composite Phosphorus,total 0.10 24 hr Composite Total oil and grease(HEM) 5 mg/L Grab Total petroleum hydrocarbon 5 mg/L Grab (SGT-HEM) Chloride 0.1 mg/L 24 hr Composite Organics ---- Grab Pesticides ---- Grab Chemical oxygen demand(COD) 50 mg/L 24 hr Composite Sampling,preservation, and analytical method must be from 40 CFR 136. * Graphite Furnace Determinations are required to attain the desired detection level for the metals. However, analysis of aeration basin and sludge to disposal samples often cannot meet these detection levels. In this case,analysis of these samples must obtain a detection level at least as stringent as the applicable inhibition criteria or sludge ceiling standard. ** All aeration basin and sludge to disposal samples will be grab. Twelve Mile Creek LTMP Page 6 Union County Public Works Long Term Monitoring Plan—Twelve Mile Creek WRF Twelve Mile Creek LTMP Page 7 Union County Public Works Long Term Monitoring Plan—Twelve Mile Creek WRF H. WWTP Diagram Legend: FBW =Filter Backwash FM =Force Main RAS =Return Activated Sludge WAS =Waste Activated Sludge MLSS =Mixed Liquor Suspended Solids GBT =Gravity Belt Thickener # =Sampling Point MLSS u Aeration Basin "-' Distribution Coarse Influent Fine Grit Distribution Box Aeration Basins Box (Screens Pump Station Screens Removal influent �I 1� ► "-_ —�'Q_44—� ► ►j To I A A I _ McAlpine 18"FM Creek e WWMF y RAS (CMU) Grit Diversion Pump Station Twelve Mile Creek Tertiary Fiken 14— , Clarifiers Cascade UV Disinfection Aerator FBW RAS Pump Station • In-Plant Pump Station Supernatant WAS Pump Station 14-014-1 HJ © _. Sludge GBT Aerobic Transfer Aerated Digestion Station Solids Holding To Land Tank Application ivirompillit Figure 1 WWTP Process Flow Diagram Union County,NC Twelve Mile Creek WWTP NC0085359 30831-052-001 Figure 01 Twelve We Creek.aer Twelve Mile Creek LTMP Page 8