On 31 October 2006, the Southwest Research Institute (SWRI) inspected Larry's Texaco retail station located at 52413 Columbia River Highway, Scappoose, OR 97056. During the inspection SWRI collected a sample of diesel fuel from a tank that displayed an Ultra Low Sulfur Highway Diesel Fuel (ULSD) label. SWRI analyzed the sample and determined that the sulfur content of the fuel was 23 parts per million (ppm), in violation of the maximum 15 ppm standard. As the supplier of the fuel to the retail station, Respondent was liable for the violation. Respondent corrected the violation by immediately downgrading the fuel to low sulfur, and by supplying ULSD fuel that had a sulfur content of 6 ppm.