Exxon Corp. has submitted its 1990 work program for cleaning up remnants of the Exxon Valdez oil spill to Coast Guard Rear Adm. David E. Ciancaglini, the federal on-scene coordinator of the spill site.
The company said in its Apr. 27 submittal it plans to employ small mobile squads of workers using techniques that are least intrusive on the environment, said Otto Harrison, general manager of Exxon's Alaska operations. The Coast Guard in late March approved Exxon's preliminary cleanup plan, and work was to begin May 1 (OGJ, Apr. 9, p. 32).
Exxon drafted the work program using the March planning document, results of the joint spring shoreline survey (JSSS), reviews by a joint technical assessment group (TAG), and knowledge the company gained from its 1989 cleanup efforts.
Harrison says Exxon has arranged for a fleet of boats, helicopters, and airplanes. The company proposes using eight mobile teams supported by eight berthing vessels and 12 landing craft.
It plans to assist those groups with a force of 24 helicopters, 10 other aircraft, 20 work boats, eight supply boats, and about 30 smaller boats and skiffs.
The teams will apply five cleanup techniques:
- Bioremediation for surface and subsurface treatment.
- Manual pickup of oiled debris and tarballs.
- Tar mat removal.
- Spot washing using hand held units.
- Tilling and raking of sediments.
Six teams will conduct manual/mechanical cleanup, and two will apply bioremediation treatments.
SHORELINE SURVEY
The JSSS was conducted by officials of the U.S. government, Alaska, Exxon, and others. It shows that conditions in Prince William Sound and the Gulf of Alaska have improved greatly, Harrison said, as a combined result of last year's cleanup effort and the natural effects of harsh winter storms.
As of Apr. 20, 574 miles of shoreline had been surveyed. The results show no evidence of surface oil on 372 miles (65%), very light oiling along 130 miles (22%), and a narrow to wide band of weathered crude on 72 miles (13%).
"The remaining oil is on generally short lengths of shoreline in scattered locations," Harrison said.
JSSS data also show about 16 miles with some subsurface oil. Analyses of soil samples in this area indicate levels of oil content averaging 0.1 wt % and 1% of the pore space.
Exxon will update the work program after all agreed JSSS locations have been surveyed, and TAG recommendations have been made and cleared by Ciancaglini.
By June 1, Exxon expects to increase its total number of Alaskan cleanup workers, including field operations and onshore support, by about 400 to about 1,100.
Copyright 1990 Oil & Gas Journal. All Rights Reserved.
