Document wgjEgoV91zpz882man5z3DjE6

Compliance Evaluation Inspection Report Timber Lake Service July 2024 Submitted to: U.S. ENVIRONMENTAL PROTECTION AGENCY REGION 8 1595 Wynkoop St. Denver, CO 80202 Submitted by: Eastern Research Group. 14555 Avion Parkway, Suite 200 Chantilly, VA 20151 EPA Contract No. 68HERC21D0007 Task Order 68HERC22F0492 COMPLIANCE EVALUATION INSPECTION REPORT Date of Report: July 9, 2024 Date and Time of Inspection: May 16, 2024 at 7:50 AM MST Weather: Partly Cloudy, 53 Fahrenheit Facility Contact/Owner: Owner Address: 824 Main Street Timber Lake, South Dakota 57656 Facility Address: 824 Main Street Timber Lake, South Dakota 57656 Facility Phone: Facility ID Number: 4020017 Reason for Inspection: Compliance Inspection Inspector(s): , ERG (Lead) Timber Lake Service CEI Report ii July 2024 TABLE OF CONTENTS 1. NARRATIVE ..................................................................................................................... 1 2. SUMMARY ........................................................................................................................ 4 ATTACHMENTS Attachment A: Attachment B: Attachment C: Attachment D: Attachment E: Attachment F: EPA Region 8 UST Compliance Checklist Photograph Log Cathodic Protection Test Monthly and Annual Walkthrough Inspections Facility Letter of Credit Notice Of Inspection Timber Lake Service CEI Report iii July 2024 1. NARRATIVE The Region 8 (R8) office of the Environmental Protection Agency (EPA) requested multiple facilities be inspected on tribal lands. Eastern Research Group (ERG) under EPA's Contract No. 68HERC21D0007, Task Order 68HERC22F0492, provided assistance to EPA in preparing for, conducting the inspection, and preparing this inspection report. ERG inspected Timber Lake Service located in Timber Lake, South Dakota on May 16, 2024. The facility was last inspected on June 30, 2021. , contract inspector for EPA, contacted Mr. , the owner and representative of Timber Lake Service, to notify the facility about the inspection on April 26, 2024, prior to the inspection. The inspection verified compliance with the federal underground storage tank (UST) requirements of Resource Conservation and Recovery Act (RCRA) Subtitle I under 40 CFR Part 280. Upon arrival at the facility, Ms. introduced herself as a contract inspector for EPA, presented her credentials, and provided an in-brief to Mr. . Ms. concluded with an exit brief to inform the facility of preliminary observations identified during the inspection and had Mr. sign the Notice of Inspection. Ms. took photographs during the inspection. UST System Description Timber Lake Service (facility) is a privately-owned gas station located at 824 Main St, Timber Lake, SD 57656. The facility is located on the Cheyenne River Indian Reservation. Fuel stored at this facility is sold to the public. According to the previous EPA inspection report and observations made during the inspection, the facility has four STI-P3 underground storage tanks (USTs) installed in September 1990. Tank 1 has a capacity of 2,000 gallons and contains unleaded gasoline. Tank 2 has a capacity of 2,000 gallons and contains E10 gasoline. Tank 3 has a capacity of 2,000 gallons and contains diesel. Tank 4 has a capacity of 2,000 gallons and contains diesel. The dispensing system for each of the tanks is European Safe Suction and is constructed using single-walled FRP. Ms. completed an EPA Region 8 UST Compliance Inspection Checklist for the USTs while on site which is included in Attachment A. Photograph #1 in Attachment B shows the dispensers and an overview of the UST system. UST System Records The listing of documents reviewed for the Timber Lake Service inspection included the following: 1. UST Leak Detection Records 2. Cathodic Protection Test Records 3. Letter of Credit 4. Facility Monthly and Annual Walkthrough Inspections Timber Lake Service CEI Report 1 July 2024 The facility maintains all records on site. Mr. the inspection. provided the records for the UST during Tank Release Detection The facility uses an EDW Autostik Series 940 monitoring system and associated in-tank probes that conduct automatic tank gauging (ATG) of the tanks. Mr. provided the last 12 months of passing leak detection results. Passing ATG Operational Testing was not provided during the inspection. Photograph #2 in Attachment B shows the monitoring system interface. Piping Release Detection Piping leak detection is not required because this facility has safe suction piping. This was confirmed during the physical site inspection. Spill/Overfill Prevention Spill and overfill prevention equipment tests were not provided for review during the inspection. The previous spill bucket and overfill prevention equipment test was conducted in October 26, 2020. The tanks are equipped with spill buckets during the physical inspection, butterfly valves were noted in the fill pipes. Photographs #3 through #6 in Attachment B show the fill ports for the four USTs. Corrosion Protection Cathodic Protection (CP) is required for the tanks and is provided by a sacrificial anode system. A copy of the last CP test was available on the site dated May 3, 2023. The most recent CP test result is included in Attachment C. Operator Training Certificates for the Class A and Class B operator were presented during the inspection. is the Class A and Class B designated operator. Mr. maintained a list of Class C trained operators with certificates from the State of South Dakota. Walkthrough Inspections Records of the monthly and annual walkthrough inspections were available for review during the inspection. Attachment D includes the monthly and annual walkthrough inspection records. Financial Assurance In South Dakota, financial coverage for owners/operators of regulated USTs is provided through the South Dakota Petroleum Release Compensation Fund. Mr. had a copy of the letter from the state indicating facility coverage as well as a letter of credit on file. Attachment E includes the letter of credit for the facility. Physical Inspection During the site visit, Ms. reviewed documents onsite and observed the fill ports, both dispensers, and the ATG monitoring interface for the four USTs on site. Photograph #2 in Timber Lake Service CEI Report 2 July 2024 Attachment B shows the interface for the EDW Autostik ATG system. Ms. also observed the spill bucket and fill pipe for the four USTs. The spill buckets for all four USTs were dry and in good condition at the time of the inspection. The access ports for ATG probes were also present for each of the tanks, and no issues were noted for these during the inspection. There were two double-sided pump dispensers on site, one for diesel and one for gasoline/E10, and both dispensers were opened as part of the inspection. The safe suction system was observed, and Ms. did not observe signs of leaks at the time of the inspection. Photographs #7 through #10 in Attachment B show the safe suction systems and piping in each dispenser. A monitoring well was observed at the tank field during the inspection. Vent lines are located northeast of the USTs against the convenience store, and no obstructions or concerns were noted for the vent lines at the time of the inspection. Timber Lake Service CEI Report 3 July 2024