Document m4YvZj41JLXr7O3d1wwr6B4b

Ref: 8 Montana SENT VIA EMAIL DIGITAL READ RECEIPT REQUESTED Christopher M. Dschaak City of Wolf Point 201 Fourth Avenue South Wolf Point, Montana 59201 Wpmayor@nemont.net Re: Inspection Report for City of Wolf Point Wastewater Treatment Facility, NPDES Permit No. MT0030571 Dear Mayor Dschaak: On July 23, 2024, a representative of the U.S. Environmental Protection Agency inspected the City of Wolf Point's Wastewater Treatment Facility in Wolf Point, Montana, to evaluate compliance with the site's National Pollutant Discharge Elimination System permit for wastewater discharge. The inspection was conducted under the authority of Section 308 of the Clean Water Act. Enclosed is a report of the inspection. Inspection findings are summarized within the enclosed inspection report in a table titled "Findings, Corrective Actions and Recommendations." Within thirty (30) days of receipt of this report, please provide the EPA with a summary of corrective actions taken to address each of the findings identified in the report and any information that may change the findings or content of the report. This summary should be sent to: Lisa-kay Prideaux U.S. EPA Region 8 - Montana Office Prideaux.lisakay@epa.gov Wilfred Lambert Fort Peck Acting Environmental Director wlambert@fortpecktribes.net Please contact me at 406-457-5022 or Prideaux.Lisakay@epa.gov if you have any questions regarding this letter or the enclosed report. Sincerely, Prideaux, Digitally signed by Prideaux, LisaKay LisaKay Date: 2024.12.18 14:00:53 -07'00' Lisa-kay Prideaux NPDES and Wetlands Enforcement Section Enforcement and Compliance Assurance Division Enclosures: NPDES Inspection Report - POTW Photo Log cc (electronic): The Honorable Justin Gray Hawk Sr., Chairman, Assiniboine and Sioux Tribes Wilfred Lambert, Acting Environmental Director, Assiniboine and Sioux Tribes Ken Luckow, Public Works Director, City of Wolf Point NPDES Wastewater Inspection Report National Database Information Inspection Date: July 23, 2024 Inspection Type: CEI, Minor POTW Entry/Exit Time: 08:30 / 11:30 NPDES ID Number: MT0030571 NAICS Code: 221320 (Sewage Treatment Facilities) Inspection ID: 202407_MT0030571 Lead inspector and affiliation: Lisa-kay Prideaux, U.S. EPA Region 8, Montana Office Inspector and affiliation: Facility Location Information Site/Facility Name & Location: Wolf Point Wastewater Treatment Facility 205 E. Idaho Street Wolf Point, Montana 59201 E-mail Report to: Christopher M. Dschaak, Mayor WPmayor@nemont.net Contact Information Facility Contacts: Person/Company meeting definition of "Operator" per the Permit Authorized Official(s) Name(s)/Title Ken Luckow, Public Works Director (present) Bill MacDonald, Assiniboine and Sioux Tribes (present) Christopher M. Dschaak - Mayor (not present) Ken Luckow - Public Works Director (present) Permit Information Is the permit on site and available? Yes Effective Date: July 1, 2018 Expiration Date: June 30, 2023 (Administratively extended) Facility Latitude: 48.081765N Facility Longitude: 105.634046W Receiving Water(s): Missouri River Regulatory Inspector's source of information: Permit, Statement of basis, previous inspection, Integrated Compliance Information Systems (ICIS), Enforcement & Compliance History Online (ECHO), facility representatives and field observations. Areas Evaluated During Inspection Permit Effluent/Receiving Waters Records/Reports Flow Measurement Facility Site Review Self-Monitoring Program Compliance Schedule Pollution Prevention Laboratory MT0030571 Wolf Point Wastewater Treatment Facility Page 1 of 8 Report Review and Signature Drafter: Lisa-kay Prideaux Digitally signed Prideaux by Prideaux, LisaKay , LisaKay Date: 2024.12.18 14:01:20 -07'00' Reviewer Name: Brit Rustad Management Signature/Name EMILIO Digitally signed by EMILIO LLAMOZAS LLAMOZAS 13:56:50 -07'00' Date: 2024.12.18 Emilio Llamozas Address/Phone Number U.S. EPA Region 8, Montana Operations Office 10 West 15th Street, Suite 3200 Helena, Montana 59626 406-457-5022 Address/Phone Number U.S. EPA Region 8 1595 Wynkoop Street 8ENF-W-NW Denver, Colorado 80202 303-312-6885 Address/Phone Number U.S. EPA Region 8 1595 Wynkoop Street 8ENF-W-NW Denver, Colorado 80202 303-312-6407 Date 12/11/2024 Date 12/16/2024 Date 12/16/2024 Inspection Narrative and Site Description Entry/Introduction On Tuesday, July 23, 2024, I, U.S. Environmental Protection Agency (EPA) inspector Lisa-kay Prideaux, along with Bill MacDonald of the Assiniboine and Sioux Tribes (Tribes), conducted a compliance evaluation inspection of the Wolf Point Wastewater Treatment Facility (facility), located in Wolf Point, Montana, to evaluate compliance with the facility's National Pollutant Discharge Elimination System (NPDES) Permit No. MT0030571 (Permit). According to the previous inspection report, the facility is owned and operated by the City of Wolf Point (City). The inspection was coordinated with the City several weeks in advance. Throughout the inspection, the inspector noted observations in bound notebooks and checklists which reflected conditions of the Permit. Photographs taken during the inspection are included in the attached photo log and are maintained by EPA in accordance with the Quality Assurance Field Activities Procedure and Standard Operating Procedure. The inspection commenced at approximately 08:30, when the inspector arrived at the facility and met with facility representative Ken Luckow, Public Works Director, and Bill MacDonald, an Assiniboine and Sioux Tribal representative. The group convened around a conference table in the control building where the inspector presented credentials and outlined the intended format and scope of the inspection. We then began the discussion portion of the inspection, where the facility representative provided an overview of the wastewater operations, O&M Program, monitoring procedures, lift MT0030571 Wolf Point Wastewater Treatment Facility Page 2 of 8 stations, collection systems, and active and planned projects within the collection system and at the lagoon. The inspector verified previously documented information (Statement of Basis and/or 2019 compliance inspection report) as well as gathered current information from Ken regarding the history and existing status of the wastewater facility, collection system, and contributing community. The wastewater treatment system is a three-cell aerated lagoon serving approximately 2,500 residents. The system was originally constructed in 1956, with several modifications, the last in 2005. The facility consists of a collection system with two lift stations, 2 aerated lagoon cells, and a polishing pond. The facility system starts with a collection system containing two lift stations (Main and Birch Street) and approximately 160 manholes. The collection system is 100 percent separate sanitary sewer lines and comprised mostly (approximately 80%) of clay; however, the facility is transitioning to PVC as funding allows. The collection system transports wastewater to the lagoon system for treatment. Lagoon cells 1, 1a, and 2 are designed to operate in series or in parallel. To start the lagoon treatment process, Cells 1 and 1a (when operating in parallel) receive raw sewage from a forced main from the Main lift station. Cell 1 and Cell 1a are approximately 4.5 acres each and aerated. Cell 2 is approximately 42 acres and has an overflow pipe as an emergency structure if capacity is exceeded. See Figure 1 in the site review section for a diagram of system flows. There are two buildings on site; one is the main lift station building located north of the lagoon cells and includes the Main lift station with a grit chamber and muffin monster, four pumps for the Main lift station, a backup generator for the Birch Street lift station, and an old laboratory. The second building is a blower house building located in the southeast corner of cell 1a and includes five pumps to generate air for cells 1 and 1a. The facility intermittently discharges to a ditch leading to the Missouri River. The average design flow rate of the facility is 0.420 mgd, with a maximum annual average flow rate of 0.372 mgd and a maximum daily flow rate of 1.233 mgd. There are no industrial users that discharge to the facility. Sludge has not been removed from the cells since 2003/2004; however, a sludge judge assessment was completed in 2020. Records Review Records for the past three discharges were requested for review in an email dated July 1, 2024, prior to the inspection. Records were made available to review on-site for discharges occurring from April 10 through May 7, 2023, as an emergency discharge due to a broken valve on the discharge pipe. The emergency discharge was immediately followed by a regular discharge occurring from May 8 through May 22, 2023. The inspector also reviewed an emergency discharge occuring from April 8 through 30, 2024, due to the pond height and frozen conditions. The last discharge reviewed occurred from May 13 through 22, 2024. The following records were reviewed: x Copy of NPDES permit #MT0030571. x Effluent flow values for the past 3 discharges for outfall 001. o Evaluated records for required reporting values. x In-house results for pH for the past 3 discharges for outfall 001 and 001R. o Evaluated records for reported minimum and maximum concentration values. x Laboratory analytical results for Escherichia coli (E. coli) bacteria for the past 3 discharges for outfall 001. o Evaluated records for reported geometric mean values. x Laboratory analytical results for biochemical oxygen demand, total suspended solids, dissolved oxygen, nitrate + nitrite, total kjeldahl nitrogen, and total phosphorus for the past 3 discharges MT0030571 Wolf Point Wastewater Treatment Facility Page 3 of 8 for outfall 001. o Evaluated records for reported concentration values. x Laboratory analytical results for total ammonia nitrogen for the past 3 discharges for outfall 001 and 001R. x Chain of Custody and Laboratory Analytical Reports for the past 3 discharges for outfall 001 and 001R. o Evaluated records for proper sample relinquish methods, analytical methods, and required reporting limits. x Records of Laboratory Equipment and Controls, including records of equipment calibration. x Quality Assurance Records for Process Control Monitoring. x Sanitary sewer overflow (SSO) events. x Historic effluent violations from July 1, 2021, to present. Facility Site Evaluation After the facility records review, we walked through the wastewater treatment process. We started with the on-site main lift station building (headworks) bringing influent into one of two connected chambers, flowing through a grit chamber (photos 16 & 17), and then through the muffin monster (photos 18 & 19). The lift station has two pumps which lift wastewater into a force main leading to a splitter box east of the lagoon cells. From the splitter box, the facility can direct water into any of the three cells, effectively circumventing a cell if needed. We then drove west toward cells 1 and 1a, but stopped to note a row of cattails growing just inside the eastern wall of lagoon cell 2 (photo 20). Facility representatives stated the growth is along the old causeway removed during the upgrade of splitting cell 1 into two cells and moving the dike wall to the east sometime before 2005. The inspector noted the emergency overflow pipes from cells 1 and 1a into cell 2 (photo 21). We then viewed cell 1 (photo 22) and cell 1a (photos 24, 26, 27) with aeration and the overflow pipe leading to cell 2 (photo 23). All aerators were functional at the time of the inspection. We entered the blower building located in the southeastern corner of the lagoon system to view the pumps used to blow air to the aerators in cells 1 and 1a. There are 5 pumps in the building, facility staff stated four pumps, with two pumps running at a time, rotate automatically based on hours of runtime, and the fifth pump stays as a backup (photo 28). We then drove down the southern dike wall of cell 2 (photo 31) to the southwestern corner at the discharge location. Facility staff indicated cell 2 has a stabilization mat as part of the lining in certain sections because the lagoon is so large the wave action was creating erosion problems (photo 29). The inspector noted the overflow pipe (photo 30) from cell 2 into a manhole which can lead to the Outfall 001 outlet structure. The manhole is part of a series of manholes and piping associated with the ability to bypass cell 2 and discharge from either cell 1 or 1a (photo 33). The discharge structure at Outfall 001 has a Palmer Bowles Flume with a wet well, both with a measuring chart to measure flow (photo 35). Outfall 001 pipe is a riser pipe with large rip rap rock which drains to a ditch leading to the Missouri River (photo 34). On the way around the remainder of cell 2, the inspector noted another line of sedges/cattails growing along the western end of cell 2 (photo 36). The facility has a receiving water monitoring location, Outfall 001R, which is located on the Missouri River and is used for ambient monitoring. The inspector did not inspect this ambient monitoring location. The inspector did not observe any off-site lift stations during the inspection. MT0030571 Wolf Point Wastewater Treatment Facility Page 4 of 8 Figure 1: Wastewater Treatment System Closing Conference A closing conference was held on-site with Mr. Luckow, during which I discussed preliminary findings, as well as the process for the inspection report. The inspection concluded at approximately 11:30. Findings, Corrective Actions and Recommendations Finding #1: Failure to perform and/or document self-inspections. Specifically, facility personnel indicated inspections were being completed; however, not documented. Permit requirement: Part 1.3.5 of permit number MT0030571 states "On at least a weekly basis, unless otherwise approved by the Permit issuing authority, the Permittee shall inspect its wastewater treatment facility..." Part 1.3.5.2 of permit number MT0030571 states "The Permittee shall maintain a log, in either paper or electronic format, recording the information obtained during the inspection. ... The Permittee shall maintain the log in accordance with proper record-keeping procedures and shall make the log available for inspection, upon request, by authorized representatives of the U.S. Environmental Protection Agency or the Tribes." MT0030571 Wolf Point Wastewater Treatment Facility Page 5 of 8 Corrective Action: The facility must ensure inspections are conducted and reports are written to document observations against all required permit elements. Implement corrective actions identified during inspections within the required timeframe. In the response to this report, provide EPA and the Tribes with two months of weekly inspection reports in accordance with permit requirements. Finding #2: Unmaintained vegetation within lagoon cells. Specifically, the facility's lagoon dike walls had sporadic unmaintained vegetation within the lined and riprapped areas (photos 20, 21, and 36). Excessive vegetation/grasses are starting to take root. Heavy thick roots within the lining from the wrong type of flora can compromise the integrity and greatly inhibit or degrade the lagoon and dike walls, creating leaks and potential erosion issues under the liner. Permit Requirement: Code of Federal Regulations (C.F.R.), Title 40 122.41(e) and Part 5.5 of NPDES permit #MT0030571 states "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." 40 C.F.R. 122.41(a) and Part 5.1 of NPDES permit # MT0030571 states "The permittee must comply with all conditions of this permit. Any permit noncompliance constitutes a violation of the Clean Water Act and is grounds for enforcement action; for permit termination, revocation and reissuance, or modification; or denial of a permit renewal application." In addition, EPA has developed guidance manuals on the proper operation and maintenance of lagoons. One of the guidance materials is titled `Principles of Design and Operations of Wastewater Treatment Pond Systems for Plant Operators, Engineers, and Managers" (August 2011, EOA/600/R11/088). Part 9.4.2.3 of this guidance manual indicates the following: x To maintain wave action, a pond should be free of weeds in the water or tall weeds on the banks. x Dikes should be well seeded with grasses above the water line. Grass should be mowed regularly to prevent soil erosion and insect problems. Corrective Action: The facility must remove all vegetation within the lagoon cells. In the response to this report, provide EPA and the Tribes with a description of the corrective actions taken or will take when the timing is prime to address this finding. Provide photographic evidence documenting the corrective action when complete. Finding #3: Numeric effluent limitations were exceeded. Specifically, monitoring parameter limits were exceeded at Outfall 001 during the indicated monitoring period end date. MT0030571 Wolf Point Wastewater Treatment Facility Page 6 of 8 Parameter Escherichia coli BOD5 TSS TSS BOD5 BOD5 TSS TSS Monitoring Period end date 04/30/2023 05/31/2023 05/31/2023 05/31/2023 04/30/2024 04/30/2024 04/30/2024 04/30/2024 Limit period Daily Maximum 7-day average 30-day average 7-day average 30-day average 7-day average 30-day average 7-day average Limit value 1260 cfu 45 mg/L 30 mg/L 45 mg/L 30 mg/L 45 mg/L 30 mg/L 45 mg/L Concentration reported 3654 cfu 46.0 mg/L 30.67 mg/L 46.0 mg/L 33.4 mg/L 75.0 mg/L 85.6 mg/L 114.0 mg/L % Exceedance 66% 2% 2% 2% 11% 67% 153% 185% Permit Requirement: Part 1.1.3 of NPDES permit #MT0030759 indicates the sample type, sample location, and effluent limitations set forth for identified parameters. 40 C.F.R. 122.41(a) and Part 5.1 of NPDES permit # MT0030571 states "The permittee must comply with all conditions of this permit. Any permit noncompliance constitutes a violation of the Clean Water Act and is grounds for enforcement action; for permit termination, revocation and reissuance, or modification; or denial of a permit renewal application." MT0030571 Wolf Point Wastewater Treatment Facility Page 7 of 8 Corrective Action: The facility must properly operate and maintain all facility controls to ensure discharges from the facility are within the prescribed limitations in the NPDES permit MT0030571. In response to this report, provide EPA and the Tribes with a description of the reasons for each of the effluent exceedances and corrective actions taken to address this finding. MT0030571 Wolf Point Wastewater Treatment Facility Page 8 of 8