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Home My WebLink AboutNC0026441_NOV-2020-PC-0328 NOI_20200729x� r ROY COOPER G a. 1611CHAEL S. PECAN Stie w7 S. DANIEL SMITH 9'—w r r�l i NORTHCAROUNA rn.6anmla1al Quattcy Certified Mail # 70163560000044287298 Return Receipt Requested July 29, 2020 Roy Lynch, Town Manager Town of Siler City PO Box 769 Siler City, NC 27344 SUBJECT: NOTICE OF VIOLATION & INTENT TO ASSESS CIVIL PENALTY Tracking Number: NOV-2020-PC-0328 Permit No. NCO026441 Siler City WWTP Chatham County Dear Permittee: The North Carolina Division of Water Resources conducted an inspection of the Siler City WWTP on June 3, 2020. This inspection was conducted to verify that the facility is operating in compliance with the conditions and limitations specified in NPDES Permit No. NC0026441. A summary of the findings and comments noted during the inspection are provided in the enclosed copy of the inspection report. The Reconnaissance inspection was conducted by Division of Water Resources (DWR) staff from the Raleigh Regional Office. The following violation(s) were noted during the inspection: ' Inspection Area Aerobic Digester Description of Violation Digesters A and B were almost full. The facility was using Equalization (EQ) Basins 3A and 3B as digesters at the time of inspection, which were also full. The sludge thickening basin had about two feet of space available. Sludge was being transferred from EQ Basins 3A and 3B to the sludge thickening basin at the time of site visit. Oxidation Ditches Mixed Liquor Suspended Solids (MLSS) were about 8000 mg/L, which is about 60% higher than the targeted value (5000 mg/L). Dissolved Oxygen (DO) was observed at 0.2, 0.5, 0.1, and 0.7 mg/L (from four locations in the oxidation ditches). Operations & Maintenance Poor sludge management resulted in the inability to waste sludge as needed, which led to upset conditions of the treatment plant indicated by elevated effluent Ammonia Nitrogen and BOD. DY��J hrrt .�r: •]ee rtCe• rt•-•u;e:: I >ci:r:fr.rv=6i]:.:�I is {• .rs :+c Jr! a r ?677 fwvr. 9r.* I F c c (• M1t••• Luc •a Insp ce tion XFea — — Description of Violation Secondary Clarifier The sludge blankets were high in both secondary clarifiers (Clarifier #1: 9 feet; Clarifier #2: 9.5 feet. Sidewall depth for both units is 14 feet). The site inspection revealed the following violation of NPDES permit condition (NC0026441) which states the following: NPDES Permit NCO026441 Part II. Section C.2. Proper Operation and Maintenance Proper Operation and Maintenance The Permittee shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the Permittee to achieve compliance with the conditions of this permit. Proper operation and maintenance also includes adequate laboratory controls and appropriate quality assurance procedures. This provision requires the Permittee to install and operate backup or auxiliary facilities only when necessary to achieve compliance with the conditions of the permit [40 CFR 122.41(e)]. In addition, the site visit conducted by DWR staff on July 20, 2020, revealed that the above observed conditions at the facility were not improved significantly: all sludge digesters (including EQ Basins 3A and 3B) and sludge thickening basin were full (no space for sludge wasting); MLSS were still high (around 7000 mg/L). A Notice of Violation/Intent to Issue Civil Penalty is being issued for the noted violation of North Carolina General Statute (G.S.) 143-215.1 and the facility's NPDES permit. Pursuant to G.S. 143-215.6A, a civil penalty of not more than twenty-five thousand dollars ($25,000.00) may be assessed against any person who violates or fails to act in accordance with the terms, conditions, or requirements of any permit issued pursuant to G.S. 143-215.1. If you wish to provide additional information regarding the noted violation, request technical assistance, or discuss overall compliance please respond in writing within ten (10) business days after receipt of this Notice. A review of your response will be considered along with any additional information provided. You will then be notified of any civil penalties that may be assessed regarding the violations. If no response is received in this Office within the 10-day period, a civil penalty assessment may be prepared. Remedial actions should have already been taken to correct this problem and prevent further occurrences in the future. The Division of Water Resources may pursue enforcement action for this and any additional violations of State law. If the violations are of a continuing nature, not related to operation and/or maintenance problems, and you anticipate remedial construction activities, then you may wish to consider applying for a Special Order by Consent. Reminder: Pursuant to Permit Condition 6 in Section E, the Permittee is required to verbally notify the Regional Office as soon as possible, not to exceed 24 hours, from first knowledge of any non-compliance at the facility including limit violations, bypasses of, or failure of a treatment unit. A written report may be required within 5 days if directed by Division staff. Prior notice should be given for anticipated or potential problems due to planned maintenance activities, taking units off-line, etc. Naa•.Gm�.�:: I Jr•i:r :+v: rr��u.r:r� S� a {-. F�{:n� :r, :� I ?679 Eunr ]r:� IF i :7c:@ r�.��. 41C•�6 S.�i1. If you should have any questions, please do not hesitate to contact Cheng Zhang with the Water Quality Regional Operations Section in the Raleigh Regional Office at 919-791-4200. Sincerely, OocuSigned by: UoGtn.,t,SSu. f, haln,,ud 82S16E6A1332144F Vanessa E. Manuel, Assistant Regional Supervisor Water Quality Regional Operations Section Raleigh Regional Office Division of Water Resources, NCDEQ ATTACHMENTS Cc: WQS Raleigh Regional Office - Enforcement File Laserfiche 513la a 411..615 r/[:1;!'1: ^4-IA yal:� I D ":':! i. a lr ifl:.•:li :rlb 5f 0r 5q:al:nal �£:�;£un_�i�f��l�{•h:rn United States Environmental Protecton Agency Form Approved Washington 0 C 20460 EPA 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 yrlmolday Inspection Type Inspector Fac Type 1 I� j 2 15 1 3 I NCO026441 I11 121_ 20/06103 I17 18 I o I 191 c I 20ILJ 211 1 1 1 1 1 1 1 1 1 11 I I 1 1 1 1 1 1 I 1 1 1 1_1_1_1_1 1 1 1 11 1 1 1 1.1f 6 .1_1 inspection Work Days Facility Self -Monitoring Evaluat:on Rating B1 CIA --- ------- Reserved. 67 70LJ 711tyI 72 LNJ 73�4 7 I I I I I sa Section B: Facility Data Name and Location of Facility Inspected (For Industriai Users discharging to POTW. also include Entry Tme/Date Permit Effective Dale POTW name and NPDES oermit Number) 10:OOAM 20106/03 19/05/01 SVer City WWTP 370 Waste Treatment Plant Rd Exit TimelDate Permit Expiration Date Siler Gty NC 27344 11.30AM 20/06/03 19/05131 Name(s) of Onsite Representative(s)tTtles(s)lPhone and Fax Number(s) Other Facility Data 111 Brittany Nicole York1ORC1919-742-45811 Chris McCorquodale/super wwtp/1 Name. Address of Responsible OfficialMtlelPhone and Fax Number Contacted Roy Lynch,PO Box 769 Siler City NC 273441Town Manager1919-742-45811 No Section C: Areas Evaluated During Inspection (Check only those areas evaluated) Operations & Maintenar E Sludge Handling Dispo_ Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary) (See attachment summary) Name(s) and Signature(s) of Inspeclor(s) Agency/Office/Phone and Fax Numbers Date Cheng Zhang Docusipnedby: DWRIRRO W01919-79142001 7/29/2020 v8171508ETC41F . 5ignalurga fuigne orment O A Reviewer Agency/Office/Phone and Fax Numbers Dale FDWR/RRO/919-791-4232 7/29/2020 EPA form 3560 3 (Rev 9.94) Previous editions are obsolete. Page# NPDES yrlmolday Inspection Type (Cont.) NC0026441 I11 12 20/06/03 17 18 1 R t Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary) Cheng Zhang visited the plant this morning, met with Chris McCorquodale, Public Works and Utilities Director, Brittany York, WWTP ORC, and Joey Smith, collection system ORC. At the time of visit, the plant was under "normal" operational mode. Here are some items I noted: • The plant still did not have enough storage space to waste sludge, as a result, MLSS was high (around 8000 mg/L), targeted range is from 4000 to 5000, settleometer reading was 535 (1-hour) and 700 (30-min), mixed liquor DO was 0.2, 0 5, 0.1, and 0.7 mgA_ (from four locations in oxidation ditches) • Equalization basins 3a and 3b (converted from old clarifiers) were used to hold wasted sludge, which were almost full (less than 1 ft to the V-notch), sludge from 3a and 3b was being transferred to sludge thickening basin at the time of visit to get space for sludge wasting_ With EQ basins 3a and 3b being occupied, the plant has less EQ space during storm events (EQ basin 2 has capacity of 2 million gallons, not in use at the time of visit; EQ basin 1 (250,000 gallons) contains overflow from influent pump station wetwell); • Sludge thickening basin (with capacity of 768,000 gallons, 15 feet deep) had about 2 feet space available, Synagro was scheduled to haul 900,000 gallons sludge next Monday (June 8); • Filter backwash basin (with same dimension as sludge thickening basin) had about 4 feet space available; four tertiary filters were all on line. The filters have design capacity of 4 million gallons, once flow is more than that, filters have to be partially bypassed; • Due to high MLSS, sludge blankets were high in both secondary clarifiers (#1, 9 feet, #2, 9.5 feet, sidewall depth is 14 feet), ORC stated that normal blanket would be 3 to 5 feet; • ORC stated that during high flow periods (while filters were bypassed), aerators at both oxidation ditches were turned off to prevent loss of solids, resulted in very little nitrification at the ditches and higl' ammonia in the effluent. ORC also stated that they planned to add one more aerator to the ditches in order to have higher DO in the ditches. They also plan to try limited aeration (instead of no aeration at all) at ditches during future storm events. Chris mentioned that an agreement had been reached recently among the Town, DWR, and Friends of Rocky River. By the end of 2023, the WWTP upgrade will be completed. Plant upgrade include add one more oxidation ditch, one more clarifier, four more tertiary filters, and sludge handling facility (belt press), all three oxidation ditches will have BNR capability, flow will increase to 6 MGD (4 MGD now). Cheng Zhang also asked about I&I in the collection system and was told that the Town has just completed a $3M project in the North Avenue pump station area (sewer main and lateral replacement, area with repeated SSOs in 2018 hurricanes). The Town is also in planning stage to rehab sewer around Elder Road pump station (Blood Run Creek), including relocate the pump station (right now in flood zone) and sewer interceptor replacement. Page# Permit: NCO026441 Inspection Date: 06l0312020 Owner - Facility: 5iler City VWti TP Inspection Typo: Reconnaissance Operations & Maintenance Is the plant generally clean with acceptable housekeeping? Does the facility analyze process control parameters, for ex: MLSS, MCRT, Settleable Solids, pH, DO, Sludge Judge, and other that are applicable? Comment: MLSS. DO, pH. sludge blankets. etc. Oxidation Ditches Are the aerators operational? Are the aerators free of excessive solids build up? # Is the foam the proper color for the treatment process? Does the foam cover less than 25% of the basin's surface? Is the DO level acceptable? Are settleometer results acceptable (> 30 minutes)? Is the DO level acceptable?(1.0 to 3.0 mgll) Are settelometer results acceptable?(400 to 800 mlll in 30 minutes) Yes No NA NE ■ ❑ ❑ ❑ EEl ❑❑ Yes No NA NE ❑ ❑ ❑ ■❑❑❑ M ❑ ❑ Cl e❑❑❑ ❑ ■ ❑ ❑ ❑ ❑ ❑ N ❑ ❑ ❑ Comment: MLSS were about 8000 mg/L about 60% higher than targeted value 15000 mg/L). DO was 0_2. 0.5. 0.1. and 0.7 mg/L (from four locations in oxidation ditches) Secondary Clarifier Is the clarifier free of black and odorous wastewater? Is the site free of excessive buildup of solids in center well of circular clarifier? Are weirs level? Is the site free of weir blockage? Is the site free of evidence of short-circuiting? Is scum removal adequate? Is the site free of excessive floating sludge? Is the drive unit operational? Is the return rate acceptable (low turbulence)? Is the overflow clear of excessive solids/pin floc? Is the sludge blanket level acceptable? (Approximately Y4 of the sidewall depth) Yes No NA NE )♦ ❑ ❑ ❑ • ❑ ❑ ❑ • ❑ ❑ ❑ • ❑ ❑ ❑ • ❑ ❑ ❑ • ❑ ❑ ❑ • ❑ ❑ ❑ • ❑ ❑ ❑ • ❑ ❑ ❑ ❑ ❑ ❑ ❑ N ❑ ❑ Comment: sludge blankets were high in both secondary clarifiers #1 9 feet #2 9.5 feet sidewall dg tt is 14 feet Aerobic Digester Is the capacity adequate? Yes No NA NE ❑ ■ ❑ ❑ Page# 3 Permit: NC0026441 Owner - Faciiity_ Siier Cily VVVVTP Inspection Date: 06/03/2020 Inspection Typo; Reconnaissance Aerobic Digester Yes No NA NE Is the mixing adequate? Is the site free of excessive foaming in the tank? # Is the odor acceptable? # Is tankage available for properly waste sludge? ID N❑ ❑ Comment; DiciesterA and B were almost full the facility was using EQ Basin 3A and 3B as digesters at the time of ins ection which were also full_ Slud a thickening basin had about two feet space availabe. Sludge was being transfered from EQ Basins 3A and 3B to the sludge thickening basin at the time of site visit. Page# 4