Unified Command: TAPs PS-10 Electrical Isolation Joint Weep

Location: Pump Station 10 is located along the Richardson Highway Milepost 219 (Trans-Alaska Pipeline Systems [TAPS] Pipeline milepost 585.91). Pump Station 10 has been out of service since 1998; however, the station is being used today to support operations along the TAPS.
Time/Date: APSC employees discovered the spill along the Pump Station 10's main line at 5:00 p.m. on May 29, 2015. APSC reported a slow weeping of crude oil from a fitting on the TAPS main line to ADEC at 5:15 p.m. on the same day.
Spill Id: 15309914902
Product/ Quantity: The spilled product from the isolation fitting just north of TAPS Pump Station 10 is Alaska North Slope (ANS) crude oil. This is based on the laboratory sample results. The initial weep rate was about one drip per second. Oil had accumulated within the tar membrane/packing material that covered the coupling and dripped from the fitting once the soil surrounding the pipe was removed. When the tar membrane and tar were removed from the pipe, no active weeping was immediately observed. However, small dampened areas started to appear at a later time on the coupling surface, indicating weeping from the joint was still active.
Cause: The release was found during excavations to investigate a corrosion inspection anomaly in a separate location along the main line. APSC personnel then discovered discolored gravel at the leaking isolation fitting joint.