PSTD's Compliance and Inspection Department has 23 Fuel Inspectors that inspect underground and aboveground storage tanks at 5086 facilities in use throughout the state of Oklahoma. Our Inspectors perform Compliance Inspections annually and Station Inspections every 6 months at retail facilities. Inspectors review environmental and equipment testing records, verify accurate meter calibration, check tanks for the presence of water, measure octane rating, and observe fuel quality. Our Division also investigates consumer complaints regarding these items. White calibration stickers are placed on the face of each dispenser/pump by the Fuel Inspector when meter calibration is measured. This sticker is an indication to the public that calibration of this meter was verified by a Fuel Inspector during the month and year indicated on the sticker.