Document 4kmEL5zjO7xpqoDem4yNjbON

NPDES Inspection Report - Hydrostatic Testing National Database Information Inspection Date: July 23, 2024 Inspection Type: Hydrostatic Testing Entry/Exit Time: 1100 / 1300 NPDES ID Number: MT0030791 NAICS Code: 562910 Remediation Inspection ID: 202407_MT0030791 Services Lead inspector and affiliation: Lisa-kay Prideaux, U.S. EPA Region 8, Montana Operations Office Facility Location Information Site/Facility Name & Location: TC Energy Northern Border Pipeline Gas Transmission Pipeline Wolf Point, Montana Mail Report to: Jackson Lamb Jackson_Lamb@TCenergy.com Contact Information Facility Contacts: Person/Company meeting definition of "Operator" Authorized Official(s) Tribe Representative(s) Indian Health Service Representative(s) Name(s)/Title Jackson Lamb, Senior Environmental Specialist, TC Energy (not present) Dean Keplin, Area Manager, TC Energy (present) Tyler Livingston, TC Energy (present) Tyson Knodel, TC Energy (present) Bobbie O'Connell, TC Energy (present) Jackson Lamb, Senior Environmental Specialist, TC Energy (not present) Jackson Lamb, Senior Environmental Specialist, TC Energy (not present) None present None present Permit Information Is the permit on site and available? Yes Effective Date: October 1, 2022 Latitude: 48.417275N Expiration Date: September 30, 2027 Longitude: 105.536788W TC Energy - Northern Border Pipeline MT0030791 Page 1 of 4 Receiving Water(s): various locations specified in NPDES Permit Regulatory Inspector's source of information: Permit, Statement of Basis, EPA records, facility representatives, and facility observations. Areas Evaluated During Inspection Permit Records Facility Site Review Effluent/Receiving Waters Flow Measurement Self-Monitoring Program Compliance Schedule Laboratory Operations and Maintenance Sludge Handling/Disposal Pretreatment Pollution Prevention Stormwater Combined Sewer Overflow Sanitary Sewer Overflow Report Review and Signature Drafter Signature/Name Address/Phone Number Prideaux Prideaux, LisaKay 10 West 15th Digitally signed by U.S. EPA Region 8, Montana Operations Office Street, Suite 3200 Date: 2025.01.23 , LisaKay 11:27:08 -07'00' Helena, Montana 59626 Lisa-kay Prideaux Reviewer Name Jennifer Ferrando Management Signature/Name EMILIO Digitally signed by EMILIO LLAMOZAS LLAMOZAS 09:53:46 -07'00' Date: 2025.01.23 Emilio Llamozas 406-457-5022 Address/Phone Number U.S. EPA Region 8 1595 Wynkoop Street Denver, Colorado 80202 303-312-6601 Address/Phone Number U.S. EPA Region 8 1595 Wynkoop Street Denver, Colorado 80202 303-312-6407 Date 01.21.2025 Date 1/21/2025 Date 01/23/2025 TC Energy - Northern Border Pipeline MT0030791 Page 2 of 4 Inspection Narrative and Site Description TC Energy owns and operates an underground natural gas pipeline system extending from Calgary, Alberta to Chicago, Illinois. A portion of this pipeline (approximately 90 miles) and one compression station are located within the boundaries of the Fort Peck Indian Reservation, which is home to the Assiniboine and Sioux Tribes ("Tribes"). The Tribes were granted treatment in a manner similar to a state (TAS) on August 29, 1996, for Water Quality Standards (WQS). The U.S. Environmental Protection Agency (EPA) has not approved the Tribes to implement the Clean Water Act (CWA) National Pollutant Discharge Elimination System ("NPDES") program in Indian country within the state of Montana. The EPA directly implements the CWA NPDES program on Indian country lands within the state of Montana. On Tuesday, July 23, 2024, EPA inspector Lisa-kay Prideaux conducted a compliance evaluation inspection of the Northern Border Gas Transmission Pipeline ("facility"), located North of Wolf Point, Montana, to evaluate compliance with the facility's NPDES Permit No. MT0030791 ("Permit"). The EPA notified the Tribes of the inspection in a letter sent July 1, 2024, and coordinated the inspection with the Senior Environmental Specialist, Jackson Lamb, several weeks in advance. The inspection began at approximately 1100 when the inspector arrived at the Wolf Point Compression Station. The inspector presented credentials to Dane Keplan, Area Manager, and Tyler Livingston, Tyson Knodel, and Bobbie O'Connell, operators for TC Energy. Throughout the inspection, the inspector noted observations in a bound notebook and checklist which reflected conditions of the Permit. No photographs were taken during the inspection. TC Energy's facility is a natural gas transmission pipeline which crosses through the Fort Peck Indian Reservation from a northwest to southeast direction crossing through both Valley and Roosevelt counties. The facility is used to transport only natural gas and does not include any current or previous liquid oil/gas (e.g., petroleum) operations, transportation or uses. Operation and maintenance activities along the facility are typically short-term construction projects that require one to two weeks to complete. The activities generally require excavation of a pipe trench to visually inspect the pipe and perform repairs, if necessary. Pipeline facilities often conduct hydrostatic testing, and subsequently discharge the water used in the process, as a result of maintenance activities along the pipeline. Hydrostatic testing is done to ensure maintenance and repair to damaged pipeline is complete and to meet the requirements of regulatory agencies. Hydrostatic testing is generally performed by sealing the piping to be tested and filling the segment with water. After the piping is full, pressure is applied and held for several hours. Following the test, the pressure is released, and the piping is drained by gravity, pump or air pressure. The permit allows the facility to withdraw hydrostatic test water from nearby surface waterbodies or use potable water that has been trucked in; no additives to the source water are allowed. Hydrostatic test discharge would typically consist of a single continuous event for each tested pipeline segment at a rate less than 1,000 gallons per minute. The duration of discharge is relative to the length and diameter of the tested pipe sections, but generally does not exceed 24 hours. After testing is complete, the test water that was withdrawn from surface water would be discharged back to its original source; potable test water is discharged to nearby surface waters either directly, or by overland flow, or collected in tanks and hauled off-site. TC Energy - Northern Border Pipeline MT0030791 Page 3 of 4 According to facility representatives, the facility does not test repaired pipelines with pressurized water. New technology allows the facility to use a `pigging' process, which uses a mechanical device that travels through the pipeline segment assessing the integrity of the pipeline. The pigging process does not use or discharge water. Facility representatives stated the facility has been using this process since the pipeline became operational and does not have any intention of hydrostatic testing pipelines in the future. The inspector discussed the option of terminating permit coverage, or not renewing coverage when the current permit coverage expires. Based on the information obtained from facility representatives, if the facility does not discharge, they do not require a discharge permit. Facility representatives stated it would be a decision for someone at the corporate level. The facility's Permit includes special conditions in addition to discharge sampling requirements. Best Management Practices are to be implemented during a discharge, inspections are to be completed and documented during a discharge, and an operations and maintenance program is to be managed. The operations and maintenance program includes having a manual, a schedule of routine operations and maintenance activities, and a logbook to document all operations and maintenance activities. Facility representatives showed the inspector an electronic program for scheduling and tracking regular maintenance and provided physical operations and maintenance logbooks detailing all activities associated with the facility as well as standard operating procedures for maintenance activities and manuals for pipelines and compression stations. The facility does not use water for testing the integrity of pipelines, therefore, the inspector did not conduct a field tour of any areas of the pipeline or compression station. A closing conference was held on-site with Mr. Keplan, Mr. Livingston, Mr. Knodel, and Mr. O'Connell, during which inspector discussed the process for the inspection report. The inspection concluded at approximately 1300. TC Energy - Northern Border Pipeline MT0030791 Page 4 of 4