Sometime between February 14 and 15, 2009, 200 barrels of crude oil and 200 barrels of produced water (salt water) were discharged from two (2) 400 barrels storage tanks as a result of a malfucntion of a control/dump valve on the heater treater unit. The spills occured over a 24 hour period and were discovered on February 15, 2009. Due to the elevation of the location of the storage tanks relative the surroundings, the discharge flowed eastward to the Little Piney Creek and westward to the Piney Creek. Both Little Piney Creek and the Piney Creek are perennial creeks and tributaries of the Belle Fourche River which is is a navigable waters of the US. The facility's SPCC plan was reviewed and found to be inadequate. The plan has been updated and is currently in compliance