Tesoro Tank Spill; Nikiski, Alaska

Nikiski, Alaska | 1995-Dec-05

Initial Notification: As the result of a frozen flow valve, an onshore Tesoro tank transferring North Slope crude overflowed into a diked area just before noon on December 5, 1995. Workers at the scene were unaware that the storm-water drain valve had been left open. This valve led to a pipeline that discharged 200 to 300 meters offshore onto the seafloor. This release was discovered by a commercial helicopter pilot who spotted the sheen shortly after the initial overflow had occurred. Weather during the spill was extremely cold with temperatures to -20?F, with only slight winds. USCG district 17. Keyword: CISPRI, sorbent boom.