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Home My WebLink AboutNC0026441_Compliance Sampling Inspection_20201001ROY COOPER Governor MICHAEL S. REGAN Secretary S. DANIEL SMITH Director Roy Lynch, Town Manager Town of Siler City PO Box 769 Siler City, NC 27344 NORTH CAROLINA Environmental Quality October 1, 2020 Subject: Compliance Sampling Inspection (CSI) Siler City WWTP NPDES Permit No. NCO026441 Chatham County Dear Mr. Lynch: On July 21, 2020, Cheng Zhang of the Raleigh Regional Office (RRO) conducted a compliance sampling inspection of the subject facility. The assistance provided by Ms. Brittany York, the operator in responsible charge (ORC), was greatly appreciated as it facilitated the inspection process. The inspection report is attached. The following observations were made: Siler City WWTP is permitted to discharge at a rate of 4.0 MGD and consists of. automatic and manual bar screens, grit collection unit, influent pump station, influent equalization basin (Zone 2), dual oxidation ditches with surface jet aeration, flow splitter box, alum feed station, lime feed station, dual secondary clarifiers, dual aerobic digesters, sludge transfer station, dissolved air flotation (DAF) unit (Used as needed), sludge thickener basin, influent equalization or sludge storage basins (Zone 3 A & B used as needed), four tertiary filters, filter backwash basin, gaseous chlorine disinfection, chlorine contact chamber, gaseous sulfur dioxide dechlorination, and step - aeration. The facility discharges into Loves Creek, which is classified C waters in the Cape Fear Basin. The current permit was modified on April 40, 2019 and expired on May 31, 2019. An interim total nitrogen load limit was added in the modified permit (effective from January 1, 2020 through December 31, 2022). Lower total nitrogen load limit will become effective on January 1, 2023. On November 30, 2018, the Division received the Town's permit renewal application for the Siler City WWTP. The Division is in the process of renewing this NPDES permit. 2. At the time of inspection, all listed treatment units were in operable conditions. Some treatment units (equalization basins and DAF unit) were not in use. Waste activated sludge was treated in the two aerobic digesters and two EQ basins, and thickened in the sludge thickener basin. It was norDE Q�� North Carolina Department of Environmental Quality I Division of Water Resources r rnani wa Raleigh Regional Office 13800 Barrett Drive I Raleigh, North Carolina 27609 oep,m ,t ie n��m.nni"i;� 919.791.4200 noted that all sludge digesters/basins were full. As a result, the facility was unable to waste sludge as needed; mixed liquor suspended solids were high (around 7000 mg/L). 3. As part of this CSI, effluent composite samples were collected using the DWR portable sampler (a grab effluent sample was also collected for analysis of fecal coliform), these samples were analyzed by DWR Laboratory. Field parameters (except total residual chlorine) were measured using a DWR YSI Proplus meter. The sampling results are summarized in the following tables: Effluent Parameter Sample Type Permit Limit (Weekly average) Result BOD Composite 7.5 mg/L 4.2 mg/L TSS Composite 45 mg/L <6.2 mg/L Ammonia Composite 3 mg/L 0.06 mg/L TKN Composite 1.2 mg/L Nitrate + Nitrite Composite 9.4 mg/L Total Nitrogen Calculated 10.6 mg/L Total Phosphorous Composite 0.5 mg/L (Quarterly average) 0.09 mg/L Fecal Coliform Grab 400 CFU /100 ml 230 CFU /100 ml Effluent - Field Parameters Parameter Sample Type Permit Limit Result Temperature Grab 29.4 °C H Grab 6-9 7.58 Dissolved Oxygen Grab >6 mg/L 7.08 mg/L 4. Influent and effluent sampling performed by the facility was observed and found to meet the permit requirements. The result of this compliance sampling inspection is compliant. If you have any questions regarding the attached reports or any of the findings, please contact Cheng Zhang at: (919) 791-4200 (or email: Cheng. zhang@ncdenr. gov). Sincerely, DocuSigned by: `/aV�.t,SSa f. 62916E6AB32144F... Vanessa E. Manuel, Assistant Regional Supervisor Water Quality Regional Operations Section Raleigh Regional Office Division of Water Resources Attachment: EPA Water Compliance Inspection Report Cc: Central Files w/attachment (Laserfiche) Raleigh Regional Office w/attachment Brittany York, ORC (electronic copy only) United States Environmental Protection Agency Form Approved. EPA Washington, D.C. 20460 OMB No. 2040-0057 Water Compliance Inspection Report Approval expires 8-31-98 Section A: National Data System Coding (i.e., PCS) Transaction Code NPDES yr/mo/day Inspection Type Inspector Fac Type 1 IN 1 2 u 3 I NC0026441 I11 121 20/07/21 I17 18I e I 19 I s I 201 I 211IIIII 111111III II III III1 I I IIIII IIIIIIIII II r6 Inspection Work Days Facility Self -Monitoring Evaluation Rating B1 QA ---------------------- Reserved ------------------- 67 I 72 I n, I 71 I 74 79 I I I I I I I80 701� I 711 L LJ L -1 I I Section B: Facility Data Name and Location of Facility Inspected (For Industrial Users discharging to POTW, also include Entry Time/Date Permit Effective Date POTW name and NPDES Dermit Number) 10:OOAM 20/07/21 19/05/01 Siler City WWTP 370 Waste Treatment Plant Rd Exit Time/Date Permit Expiration Date Siler City NC 27344 11:OOAM 20/07/21 19/05/31 Name(s) of Onsite Representative(s)/Titles(s)/Phone and Fax Number(s) Other Facility Data Brittany Nicole York/ORC/919-742-4581/ Name, Address of Responsible Official/Title/Phone and Fax Number Contacted Roy Lynch,PO Box 769 Siler City NC 27344/Town Manager/919-742-4581/ No Section C: Areas Evaluated During Inspection (Check only those areas evaluated) Operations & Maintenar 0 Records/Reports 0 Self -Monitoring Progran 0 Laboratory Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary) (See attachment summary) Name(s) and Signature(s) of Inspector(s) Agency/Office/Phone and Fax Numbers Date Cheng Zhang Docusignedby: DWR/RRO WQ/919-791-4200/ E101112020 D6171508P EC41F... Signature of Management Q A Reviewer Agency/Office/Phone and Fax Numbers Date DocuSigned by: 101112020 Sa Vcunt.S`�, DWR/RRO WQ/919-791-4232 �-- 62916HAB32144F... EPA Form 3560-3 (Rev 9-94) Previous editions are obsolete. Page# NPDES yr/mo/day Inspection Type NCO026441 I11 121 20/07/21 117 18 1 S I (Cont.) Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary) 24-hour composite effluent sample (started at 10:19 am, July 20, 2020, ended at 10:19 am, July 21, 2020, time paced, 100 ml/20 minutes) was collected using DWR portable sampler, composite samples were collected on July 21, 2020 for BOD, TSS, ammonia nitrogen, nitrate/nitrite, TKN, and total phosphorous. Effluent sample was also collected for fecal coliform. Field parameters (except total residual chlorine) were measured using a DWR YSI Proplus meter. Analytical results BOD: 4.2 mg/L; ammonia nitrogen: 0.06 mg/L; TSS: <6.2 mg/L; nitrate plus nitrite: 9.4 mg/L; TKN: 1.2 mg/L; total phosphorous: 0.09 mg/L; fecal coliform: 230 CFU/100ml. Field parameters: Temperature: 29.4 degree C; pH: 7.58; DO: 7.08 mg/L. Influent and effluent sampling and field parameter measurement condocted by the facility were observed and found to meet permit requirements. The facility was found to be compliant for the sampling compliance inspection. Page# Permit: NCO026441 Inspection Date: 07/21/2020 Influent Sampling # Is composite sampling flow proportional? Is sample collected above side streams? Owner -Facility: Siler City WWTP Inspection Type: Compliance Sampling Is proper volume collected? Is the tubing clean? # Is proper temperature set for sample storage (kept at less than or equal to 6.0 degrees Celsius)? Is sampling performed according to the permit? Comment: Effluent Sampling Is composite sampling flow proportional? Is sample collected below all treatment units? Is proper volume collected? Is the tubing clean? # Is proper temperature set for sample storage (kept at less than or equal to 6.0 degrees Celsius)? Is the facility sampling performed as required by the permit (frequency, sampling type representative)? Comment: A part needed to be replaced to perform flow proportional sampling Yes No NA NE ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ■ ❑ ❑ ❑ ■ ❑ ❑ ❑ ❑ ❑ ❑ Yes No NA NE ❑ ■ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ■ ❑ ❑ ❑ ■ ❑ ❑ ❑ Operations & Maintenance Yes No NA NE Is the plant generally clean with acceptable housekeeping? 0 ❑ ❑ ❑ Does the facility analyze process control parameters, for ex: MLSS, MCRT, Settleable ❑ ❑ ❑ ❑ Solids, pH, DO, Sludge Judge, and other that are applicable? Comment: The facility analyzes MLSS, DO, pH, sludge blankets, etc. for process control. Laboratory Are field parameters performed by certified personnel or laboratory? Are all other parameters(excluding field parameters) performed by a certified lab? # Is the facility using a contract lab? # Is proper temperature set for sample storage (kept at less than or equal to 6.0 degrees Celsius)? Incubator (Fecal Coliform) set to 44.5 degrees Celsius+/- 0.2 degrees? Incubator (BOD) set to 20.0 degrees Celsius +/- 1.0 degrees? Comment: Yes No NA NE ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ■ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ Page# 3 U.S. EPA Interim Revised NPDES Inspection Manual 12017 Wood, L.B., and Stanbridge, H.H. (1968). "Automatic Samplers," Water Pollution Control, 67(5): 495-520. D. PERMITTEE SAMPLING INSPECTION CHECKLIST A. PERMITTEE SAMPLING EVALUATION e No N/A 1. Take samples at sites specified in permit. No N/A 2. Locations adequate for representative samples. Yes o N/A 3. Flow proportioned samples obtained when required by permit. e No N/A 4. Complete sampling and analysis on parameters specified by permit. Yes No N/A 5. Conduct sampling and analysis in frequency specified by permit. Des No N/A 6. Permittee uses method of sample collection required by permit. Required method: If not, method being used is: () Grab (} Manual Composite 0 Automatic Composite es es No No No o N/A N/A N/A N/A 7. Sample collection procedures adequate: a. Samples refrigerated during compositing. b. Proper preservation techniques used. c. Containers and sample holding times before analyses conform to 40 CFR 136.3. d. Samples analyzed in timeframe needed. es No N/A 8. Facility performs monitoring and analyses more often than required by permit; if so, results reported in permittee's self -monitoring report. Yes Na N/A 9. Samples contain chlorine. Yes No N/A 10. Use contract laboratory for sample analysis. Yes No N/A 11. POTW collects samples from industrial users in pretreatment program. B. SAMPLING INSPECTION PROCEDURES AND OBSERVATIONS es No N/A 1. Obtain grab samples. No N/A 2. Obtain composite sample. L t-1kfc"'fYet~' n3� 4 Compositing Frequency: Frvto�' es No N/A 3. Refrigerate sample during compositing. No N/A 4. Obtain flow -proportioned sample. 1/I f /" a..-kf 57- No N/A 5. Obtain sample from facility sampling device. es No N/A 6. Sample representative of volume and nature of discharge. Yes Q�V N/A 7. Sample split with permittee. No N/A 8. Employ chain -of -custody procedures. es No N/A 9. Samples collected in accordance with permit. e No N/A 10. Observe excessive foam, grease, floating solids at the outfall. G % '- L15r L1/ W r 0 Gv. ,, jp 1: n .. C � c� Gn. lv �: • 3 f /t C 4-!,) 7_ a( — 2-020 Chapter 5 — Page 115 U.S. EPA Interim Revised NPDES Inspection Manual 12017 C. AUTOMATIC SAMPLER PROCEDURES AND OBSERVATIONS es No N/A 1. Sample intake tubing place in a well -mixed, representative location (0.4 to 0.6 depth). Yes No N/A 2. Individual aliquot volume checked and at least 100ml. Y No N/A 3. Proper sample tubing (Teflon TM for organics, otherwise(Tygon ) and tubing at ID at least 0.25 inch. Yes No N/A 4. Proper composite sample container (glass for organics, otherwise lastic. e No les> No N/A N/A 5. 6. Proper refrigeration (6°C or ice), with required documentation. Proper wastewater velocity in the sample tubing (at least 2 fps). Chapter 5 — Page 116