Document yrLor9Nnrw0b5Rxb5q9qVzG86

UST Inspection Report Dakota Sioux Casino Date of Report: Inspection Date & Time: Weather: Facility Owner: Facility Owner Address: June 24, 2025 May 19, 2025, at 3:15 p.m. Central Daylight Time (CDT) Windy, overcast, 50 degrees Fahrenheit Sisseton Wahpeton Oyate Tribe 12554 BIA Hwy 711 Agency Village, SD 57262 Facility Address: 16405 Sioux Conifer Road Watertown, SD 57201 Facility Representative: EPA Facility ID Number: Reason for Inspection: Inspection Team: 4030002 Routine compliance inspection Marta Grabowski, Inspector, EPA UST Program UST System Description The Dakota Sioux Casino (Facility), a Tribally-owned casino located on the Lake Traverse Reservation in South Dakota, includes a fueling station on the premises. The fuel at this Facility is sold to the public. The former C-Store next to the fueling station closed as of December 2024, according to Facility representatives. The Environmental Protection Agency's Facility records indicate that the Facility has three 15,000-gallon fiberglass reinforced plastic (FRP) underground storage tanks (UST) that were installed in 2007. Tank 1 stores regular unleaded gasoline, Tank 2 stores super unleaded gasoline, and Tank 3 stores diesel fuel. Piping for all tanks is pressurized, double-walled flex plastic. Inspection Narrative On May 19, 2025, the EPA UST program personnel conducted an inspection at Dakota Sioux Casino in South Dakota. The EPA last inspected the Facility on May 3, 2022, and they selected it for routine reinspection. Ms. Grabowski, the EPA inspector, called and emailed the Facility representative between April 15, 2025, and April 24, 2025, to schedule the inspection and provide inspection details (see Attachment A). Ms. Grabowski arrived at the Facility at 3:15 p.m. CDT and was unable to enter the C-Store, which was closed and out of use. Upon entering the casino gift shop, Ms. Grabowski met the Facility representatives, introduced herself and presented inspector credentials. A fuel station representative 4030002-Dakota Sioux Casino Page 1 of 4 5/19/2025 UST Inspection along with a member of the casino security team escorted Ms. Grabowski to the former C-Store and provided entry access. The EPA inspector proceeded to conduct a physical inspection of the UST system as well as a review of Facility records. Photographs of UST system components taken during the inspection are in Attachment B. Copies of operation and maintenance records are in Attachment C. Tank Leak Detection Tank leak detection is conducted by a Veeder Root TLS 350R automatic tank gauge (ATG), which performs continuous statistical leak detection (CSLD) for each tank. The EPA inspector printed a system setup, system status report, CSLD test results for May 19th, and liquid sensor status for May 19th. According to the system status printout, the Facility is also equipped with liquid sensors in the annular/interstitial space of each tank. A Facility representative showed 12-months (June 2024-May 2025) of passing CSLD tests, which were stored in the office at the casino. She also provided copies of the last two annual operability test forms for the ATG console and probes, dated April 29, 2025, and March 1, 2024. Both ATG test forms indicated passing results. The ATG console screen displayed an active fuel alarm for L1 (unleaded interstitial sensor). Additionally, the system status report and liquid status indicated a fuel alarm for L1 (unleaded interstitial sensor). Piping Leak Detection Piping leak detection is satisfied by electronic line leak detectors (ELLD), which perform annual 0.1 gph line tightness tests. The EPA inspector printed pressure line leak test results from the Veeder Root console, which indicated passing 0.1 gph tests for each line between November and December 2024. Copies of the last two annual operability test results for the ELLDs (missing form for the diesel LLD in 2024), dated April 29, 2025, and March 1, 2024, were provided to the EPA inspector. All available ELLD test forms indicated passing results. At the time of inspection, the ATG console screen displayed active fuel alarms for L6 (dispenser 3-4 sump sensor), and L7 (dispenser 5-6 sump sensor). Additionally, the system status report and liquid status printouts indicated active fuel alarms for L6 and L7. Cathodic Protection Cathodic protection (CP) is not required at the Facility. The portion of tanks and piping that are in contact with soil are constructed from non-corrodible materials. Periodic Testing/Inspection of Spill and Overfill Prevention Equipment A Facility representative provided copies of triennial testing records for spill buckets and overfill prevention devices (flapper valves) at the time of inspection. All equipment passed testing/inspection on April 29, 2025. Periodic Operation & Maintenance (O&M) Walkthrough Inspections Records of monthly walkthrough inspections were available onsite for January-December 2024. An annual walkthrough checklist available onsite indicated the last annual walkthrough was conducted on October 1, 2024. A Facility representative provided copies of these records to the EPA inspector at the time of inspection. Monthly walkthrough documentation for January-May 2025 was emailed to the EPA inspector a few days after the inspection on Friday, May 23, 2025. Monthly walkthrough 4030002-Dakota Sioux Casino Page 2 of 4 5/19/2025 UST Inspection inspection records from 2024 and 2025 are blank for the line item, "Review and keep current monthly release detection records." Operator Training Both Facility representatives who took part in the inspection completed UST operator training. Copies of Class A/B and Class C operator training documentation were provided to the EPA inspector. The Class A/B certificate is dated March 14, 2014, and the Class C list indicates training occurred on January 1, 2025. Financial Responsibility In South Dakota, financial coverage for regulated UST systems is provided through the South Dakota Petroleum Release Compensation Fund. Each UST facility is responsible for the deductible. At the time of inspection, a Facility representative provided a copy of the South Dakota Certificate of Financial Assurance for Petroleum Underground Storage Tanks. Physical Observations The EPA inspector viewed the spill buckets/fill pipes, under dispenser containment (UDC) sumps, tank top sumps, Tank 3 ATG riser, and the ATG console. Spill buckets were clean and dry, and flapper valves were visible in each drop tube. Liquid sensors were present in each UDC sump. The following sumps contained a significant amount of water: Tank 1 tank top sump, dispenser 3/4 UDC, and dispenser 5/6 UDC. Liquid sensors in dispenser 3/4 and dispenser 5/6 were partially submerged, which corresponded with the active alarms at L6 and L7 displayed on the Veeder Root console. Inspection Conclusions and Recommendations At the end of the inspection, the EPA inspector filled out an Onsite Deficiency Identification Form (see Attachment D), which represents initial compliance recommendations at the time of the inspection. Class C operator training documentation was provided prior to Ms. Grabowski leaving the premises, so she crossed it out on the deficiency form. On May 23, 2025, a Facility representative emailed additional monthly walkthrough documentation, as mentioned in the above paragraph. Prior to departing the Facility, Ms. Grabowski stated that a full inspection report would be forthcoming, which includes the inspection checklist (see Attachment E). Ms. Grabowski provided the Facility representative with the deficiency form and retained a carbon copy for recordkeeping. Inspection Report Attachments A. Record of communication for scheduling the inspection B. Photo log C. Facility O&M Documents D. Onsite Deficiency Identification Form E. Inspection checklist 4030002-Dakota Sioux Casino Page 3 of 4 5/19/2025 UST Inspection Signature Lead Inspector MARTA GRABOWSKI Date: 2025.06.24 11:20:46 -06'00' Digitally signed by MARTA GRABOWSKI Marta Grabowski Date of signature 4030002-Dakota Sioux Casino Page 4 of 4 5/19/2025 UST Inspection