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Field work planned on Exxon Valdez spill Researchers to continue testing technique to break down lingering oil on beaches; governments seek to refine ‘reopener’ demand Wesley Loy For Petroleum News
It’s been 23 years since the oil tanker Exxon Valdez ran hard aground in Alaska’s Prince William Sound, spilling nearly 11 million gallons of North Slope crude.
Yet response to the incident still isn’t over.
In court papers filed recently in federal court in Anchorage, the state and federal governments outline plans for summer field work to test a technique for ridding beaches of lingering subsurface oil.
The context for the field work is the unresolved issue of whether ExxonMobil owes extra money for habitat restoration.
‘Reopener’ clause Exxon paid $900 million for the spill under a 1991 civil settlement.
The settlement contained a “reopener” clause entitling the state and federal governments to request up to $100 million more for restoration projects to address unanticipated injury to habitat or species.
In 2006, the governments exercised the reopener, presenting Exxon with a comprehensive habitat restoration plan and a letter demand for $92 million to implement it.
Exxon has yet to pay the demand, and the governments so far have opted not to sue for it.
Federal Judge H. Russel Holland has declined to intercede in the matter, refusing to order Exxon to pay or to bar the government demand.
Holland has, however, asked the two sides for periodic status reports on the reopener issue.
State and federal attorneys jointly filed the latest status report on April 30.
Biodegradation testing The status report indicates the governments are working through certain research projects to “refine” the restoration plan — a plan Exxon considers invalid.
The report outlines both recent and upcoming field work.
“During the summer of 2011, a pilot study was conducted at four beaches in Prince William Sound to test the feasibility of a bioremediation technique aimed at providing nutrients and oxygen to oiled subsurface sediments to accelerate biodegradation of oil,” the report says. “An interim report describing the results of the 2011 study has been provided to the Exxon Valdez Oil Spill Trustee Council. Despite operational delays and equipment malfunctions and weather conditions which limited the study period to six weeks, rather than the planned twelve weeks, the interim report concluded that the bioremediation method used achieved reductions in the concentration of polycyclic aromatic hydrocarbons on the order of fifty percent at two of the four beaches, and the subsurface injection of oxygen and nutrients is a feasible method of accelerating biodegradation of oil on a small spatial scale at some beaches.”
The trustee council has funded additional field work this summer, the status report says.
“Specifically, the researchers will return to two of the beaches at which investigation was undertaken last year. At one of those beaches, where degradation was not observed, they will alter their method of injection to take a second look at whether natural degradation can in fact be enhanced with subsurface injection of oxygen and nutrients. At the second beach, where degradation did occur, they will conduct additional injection of oxygen and nutrients to ascertain whether degradation beyond the fifty percent level can be achieved and whether the degradation can be achieved farther seaward.”
Sea otters and ducks In addition, a team of scientists will evaluate 53 sites as candidates for bioremediation using subsurface injection, the status report says.
“This will involve both a desktop exercise and field verification at up to twenty sites,” with a final report on the work due to the trustee council by April 15, 2013.
The governments also have been continuing an evaluation of the effects of lingering oil on wildlife, including sea otters and harlequin ducks, the status report says.
The results of several wildlife studies have been published recently or soon will be, the report says.
Researchers are trying to determine “whether there are spatial linkages between the distribution of lingering oil within Prince William Sound and the distribution of” sea otters, harlequin ducks and other nearshore vertebrate species still recovering from the Exxon Valdez spill.
Overall, the governments say the information they’re gathering will determine the “next steps” in a process to decide what, if anything, should be done to restore injured habitats.
Implementing an effective treatment technology will depend on environmental benefit, costs and public input, the status report says.
It adds: “The Governments anticipate discussing with Exxon its interest in participating in those next steps and a possible resolution of the Governments’ demand to Exxon under the Reopener.”
Holland wants another status report by Sept. 28.
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