Document wrrM68wwd2yxXBMQdmM8RzbMJ

Region 6 - Enforcement & Compliance Assurance Division INSPECTION REPORT Inspection Date(s): Media Program: Regulatory Program(s) April 15, 2025 Water CWA Company Name: Facility Name: Facility Physical Location: (city, state, zip code) Mailing address: (city, state, zip code) County/Parish: Facility Phone Number Facility Contact: City of Bloomfield Bloomfield Wastewater Treatment Plant 1176 S. Church Street Bloomfield, New Mexico 87413 915 N. 1st St. Bloomfield, New Mexico San Juan 505-516-9416 David Sonnenberg Water Reclamation Superintendent dsonnenberg@bloomfieldnm.com FRS Number: Identification/Permit Number: Media Identifier Number: NAICS: SIC: 11039938930 NM0020770 N/A 221320 4952 Personnel participating in inspection: David Sonnenberg City of Bloomfield David Esparza, P.E. USEPA/R6-ECDWM Water Reclamation Superintendent Environmental Engineer EPA Lead Inspector Signature/Date Digitally signed by DAVID DAVID ESPARZA ESPARZA Date: 2025.05.27 10:57:16 -06'00' David Esparza Date Supervisor Signature/Date ROBERTO BERNIER Date: 2025.05.30 14:18:53 -05'00' Digitally signed by ROBERTO BERNIER Roberto Bernier Date 6ENFORM-020-R8.2 (02/12/2020) 1 Section I - INTRODUCTION City of Bloomfield/ Bloomfield WWTP Permit No. NM0020770 Inspection Date 04/15/2025 PURPOSE OF THE INSPECTION EPA Region 6 inspector David Esparza, PE, arrived at the City of Bloomfield Wastewater Treatment Plant (WWTP) (Bloomfield) at approximately 9:00 AM on April 15, 2025, for an unannounced Reconnaissance Inspection (RI). I met with Mr. David Sonnenberg, Water Reclamation Superintendent. I presented my credentials and informed him that this was an EPA inspection to determine the WWTP's compliance under the Clean Water Act (CWA). This RI was conducted under the authority of the National Pollutant Discharge Elimination System (NPDES) permit program, in accordance with the CWA. The generation of this report is based on information supplied by Bloomfield representatives, observations made by the United States Environmental Protection Agency (US EPA) inspector, and records and reports maintained by the permittee (Bloomfield) and the US EPA. Before leaving the facility, an exit briefing was held with Mr. Sonnenberg, to explain areas of concern noted at the time of the inspection. FACILITY DESCRIPTION The WWTP is a major discharger, with a design flow of 0.9 million gallons per day (MGD), and is located at 1176 S. Church Street, Bloomfield, San Juan County New Mexico (depicted in Aerial Image #1 below). The WWTP serves a population of approximately 7,800 residents. The WWTP is operated by staff within the Public Works Department and consists of 5 full-time equivalent (FTE) positions, inclusive of administrative support on a Monday through Friday 8-hour per day basis. On-call staff is available on an as needed basis. The head works located at the entry to the WWTP has split channels: a manual bar screen, and a mechanical grit and solids removal system inclusive of a screw pump. These split channels converge at an aerated grit chamber, thence to three (3) sump pumps that lift the influent water to the recently constructed sequencing batch reactors (SBR) and digester basins. The previous digester basins (#1 through #4), aeration basins (#1 and #2) and south clarifier are currently offline. The previous north clarifier is projected for future toxic flow storage. The previous chlorine contact chamber (CCC) has also been replaced and/or upgraded by a newly constructed chamber. Additionally, other treatment processes within the existing WWTP are currently undergoing rehabilitation and/or upgrades (depicted in Aerial Image #2 below). The city maintains 2 lift stations (Identified in Table 1 below). Table 1: City of Bloomfield Lift Stations Lift Station 1 River 2 Highway 64 Address S. Side of River on Hwy 550, Take Mangum (East), to Roberts Ln. (Turn South), to bottom of Hill (on Right Side) Take Hwy 64 West, Past Ruth Lane, On North Side of Highway in Roadrunner Carwash Lot (S.E. Corner) 2 City of Bloomfield/ Bloomfield WWTP Permit No. NM0020770 Inspection Date 04/15/2025 Aerial Image #1 Overall view of the existing City of Bloomfield's Wastewater Treatment Plant. Aerial from Google Earth. Aerial Image #2 Overall view of the existing City of Bloomfield's Wastewater Treatment Plant and the upgrades denoted in "red". Aerial from Google Earth. 3 City of Bloomfield/ Bloomfield WWTP Permit No. NM0020770 Inspection Date 04/15/2025 Decant from the digester is returned to the head works where it mixes with the raw influent. From the digester, solids are sent to the belt press, thence to the sludge drying beds. The sludge drying beds have under drains that direct liquids back to the head of the plant. Grit removed from the head works is collected in a hopper and disposed of at the landfill. Final disposal of solids is to a surface disposal site at the WCA Bondad Landfill in Durango, Colorado (County Road 318, Durango, CO 81303 (970) 2478295). Currently the only established Industrial User (IU) is Enterprise Field Services, LLC (Enterprise). Bloomfield and Enterprise entered into a wastewater treatment agreement for the disposal of their wastewater into the City's WWTP on May 1, 2022, with an expiration date of April 30, 2025. Note: The previous service agreement is currently being updated. The WWTP rehabilitation included installation of a new back-up generator in the event of an electrical power disruption or unit failure, for the entire plant and the onsite lift Station. Additionally, there is a new supervisory control and data acquisition (SCADA) and call-out system. Section II - OBSERVATIONS I observed the following and/or the following information was provided or stated on March 27, 2025. Additionally, the discussion also addressed activities associated with the scheduled rehabilitation and/or new construction identified in Administrative Order (AO) Docket Number CWA-06.2019-1778. Aeration Basins - The two (2) existing parallel aeration basins recommended for replacement in the February 2018 Preliminary Engineering Report (PER) have been replaced with new Sequencing Batch Reactor (SBR) basins, inclusive of other improvements. These newly constructed SBR basins are denoted in red in the upper portion of Aerial Image #2 and required the removal of several existing drying beds. Additionally, the new SBR basins will utilize air diffusion rather than the previous surface air paddle style mixers. The newly constructed SBR basins exhibited significant leaking at the sidewall penetrations for the air piping. The insertion of an expandable rubber seal (LINK-SEAL) failed to prevent leakage. The plastic sleeves placed during the concrete pouring for sidewall penetration were not rigid enough to prevent movement; thus, not allowing adequate contact with the expandable rubber seal. Typically, the lack of concrete vibration during the concrete pour can result in cracks and honeycombing as exhibited with the visible exterior staining and algae growth (see Appendix 1 Photograph #4, Photograph #5 and Photograph #6) of concrete. Note: LINK-SEAL is a modular, elastomer sealing system that creates a permanent, hydrostatic seal for practically any cylindrical object as it traverses through a barrier. Injection point (manway) for the sodium bisulfite lacked typical bollards or devices to prevent potential vehicular damage. Vehicle tire tracks were visible around both sides of the manway (Appendix 1 Photograph #14). Section III - AREAS OF CONCERN The following areas of concern (AOCs) were observed and discussed with the City of Bloomfield: 4 City of Bloomfield/ Bloomfield WWTP Permit No. NM0020770 Inspection Date 04/15/2025 The newly constructed SBR basins exhibited significant leaking at the sidewall penetrations for the air piping. The insertion of an expandable rubber seal (LINK-SEAL) failed to prevent leakage. The plastic sleeves placed during the concrete pouring for sidewall penetration were not rigid enough to prevent movement; thus, not allowing adequate contact with LINK-SEAL. Typically, the lack of proper concrete vibration (which removes entrapped air bubbles from fresh pours and helps it flow evenly around the reinforcement) during the concrete pour can result in cracks and honeycombing as exhibited with the visible exterior staining and algae growth (see Appendix 1 Photograph #4, Photograph #5 and Photograph #6) of concrete. This sidewall leaking and algae growth could exacerbate the degradation of the concrete and integrity of the air piping; thus, potentially lessening their service life (Appendix 1 Photograph #9, Photograph #10, Photograph #11 and, Photograph #12 and Photograph #13). Section IV - RECOMMENDATIONS Install vehicular traffic barriers i.e., bollards or similar devices around the injection point (manway) for the sodium bisulfite to prevent potential damage (Appendix 1 Photograph #14). Suggest current photographic documentation around air piping penetrations and visible exterior sidewall leakage/algae growth, thence cleaning (power washing), thence photographic documentation at the same location(s), thence periodic (recorded) photographic documentation to denote degradation of sidewall penetrations or air piping. Keep track of evidence of further degradation on a regular basis to ensure timely repairs as necessary. Section V - FOLLOW UP No additional information was received by EPA after exiting the Facility on March 27, 2025. Section IV - LIST OF APPENDICES Appendix 1 - Photo Log - 14 photos taken 03/27/2025. 5 City of Bloomfield/ Bloomfield WWTP Permit No. NM0020770 Inspection Date 03/27/2025 Appendix 1 Photograph Log UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 1 County/Parish: San Juan State: New Mexico View of air piping sidewall penetration along the southeast corner. Note: the visible leaking and staining. Additionally, the visible upper penetration is sealed on the interior of the basin. (IMG_0307). 03/27/2025 11:21 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 2 County/Parish: San Juan State: New Mexico Another view of the same sidewall penetration. (IMG_0308). 03/27/2025 11:22 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 3 County/Parish: San Juan State: New Mexico A closer view of the upper penetration along the southeast corner. Note: the potential avenue for exterior degradation or storm event intrusion. (IMG_0311). 03/27/2025 11:22 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 4 County/Parish: San Juan State: New Mexico View of the air piping support brackets approximately midway along new SBR basins. Note: the visible leaking. (IMG_0309). 03/27/2025 11:22 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 5 County/Parish: San Juan State: New Mexico Another view of leaking along the new SBR basins approximately at land surface. (IMG_0312). 03/27/2025 11:23 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 6 County/Parish: San Juan State: New Mexico View of the air piping penetrations along the Northeast corner of the new SBR basins. Note: the leaking and algae growth. (IMG_0315). 03/27/2025 11:24 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 7 County/Parish: San Juan State: New Mexico View of 2 upper sidewall penetrations along the Northeast corner of the SBR basins. Note: the leaking of the left penetration, indicative of the expandable rubber seal failure. (IMG_0316). 03/27/2025 11:25 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 8 County/Parish: San Juan State: New Mexico Close-up view of a sidewall penetration. Note: the cracking and spalling of the concrete around penetration. (IMG_0317). 03/27/2025 11:26 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 9 County/Parish: San Juan State: New Mexico Close-up view of the same air piping penetrations identified in Photo No. 6 above. (IMG_0324). 03/27/2025 11:36 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 10 County/Parish: San Juan State: New Mexico Closer view of the same air piping penetrations identified in Photo No. 6 and Photo No. 7 above. (IMG_0326). 03/27/2025 11:37 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 11 County/Parish: San Juan State: New Mexico View of the concrete degradation and algae growth along the SBR sidewall. (IMG_0327). 03/27/2025 11:37 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 12 County/Parish: San Juan State: New Mexico Another view of the concrete degradation and algae growth along the SBR sidewall. (IMG_0328). Note: the appearance of the air piping corrosion. 03/27/2025 11:38 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 13 County/Parish: San Juan State: New Mexico A clear close-up view of the concrete degradation and algae growth along the SBR sidewall. (IMG_0330). Note: the appearance of the air piping corrosion. 03/27/2025 11:39 AM Photographed by D. Esparza UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Photograph Log Location: Bloomfield WWTP City: Bloomfield Photo No. 14 County/Parish: San Juan State: New Mexico View of sodium bisulfite injection manway. Note: the visible vehicle tire marks around the manway and lack of structure protection, i.e., bollards. (IMG_0318) 03/27/2025 11:32 AM Photographed by D. Esparza