FAIRBANKS—Workers have fixed a small crude oil leak coming from the trans-Alaska oil pipeline near an inactive pump station on the Richardson Highway about 140 miles south of Fairbanks.
The Alaska Department of Environmental Conservation described the leak, discovered in late May, as a slow “weep” coming from a fitting joint on a buried portion of the 48-inch main pipeline just north of Pump Station 10. The joint leaked one drip of oil per second into packing material around the fitting and, ultimately, into surrounding soil and gravel, the DEC said in a notice.
The fitting was installed in the pipeline’s construction during the mid-1970s, DEC said.
Alyeska Pipeline Service Co. employees fabricated a 60-inch sleeve and welded it over the fitting, fully containing it, according to DEC. Workers also excavated about 15 feet of soil, roughly seven cubic yards, from below the leak.
The work was stopped when workers ran into a boulder, and some gravel could not be removed due to nearby utility lines and a valve, an updated DEC notice on Thursday said.
DEC approved backfilling to replace the removed soil on Oct. 28, but “there remains a small area of contamination unable to be excavated that will be monitored by ADEC’s Contaminated Sites Program,” the notice says. DEC said contaminated gravel had been removed “to the maximum extent practicable.”
Pump Station 10 has been out of service since 1998, but the facility is still used to support pipeline operations.
Source : newsminer.com