Expert Panel to Review DEC’s Stringent Sulfolane-Contamination Cleanup Level

Sep 5, 2014

An independent panel of experts will meet here in Fairbanks later this month to review the state environmental agency’s recommended cleanup level for sulfolane contamination in the North Pole area’s groundwater.

Flint Hills Resources Alaska shut down its North Pole refinery in May, citing economic factors that included the cost of cleaning up sulfolane that leaked from the refinery for years.
Credit Alaska Department of Environmental Conservation

Scientists with Ohio-based Toxicology Excellence for Risk Assessment, or TERA, will meet at the UAF’s Wood Center on Sept. 16 and 17 to take a second look at the stringent cleanup level set by the state Department of Environmental Conservation.

Sulfolane is an industrial solvent that leaked for years from the Flint Hills Resources refinery in North Pole. DEC says Flint Hills must reduce the level of sulfolane in the water down to 14-parts-per-billion so it’s safe to drink.

The company says the level should set at about 25 times that level – around 363 parts-per-billion. Flint Hills asked DEC to reconsider the cleanup level, and in April, Commissioner Larry Hartig agreed to take a second look.

Tamara Cardona, who heads up the DEC’s sulfolane-cleanup team, says the TERA scientists’ review is an important part of that reconsideration. She says the scientists will focus largely on the reference doses, which define the toxicity of substance, used by DEC to determine the cleanup level.

“These experts will look at the literature available, the different reference doses, and they will sit down and have a discussion during these two days and provide to DEC a report with recommendations,” Cardona said.

Flint Hills cited the costs of attaining the stringent cleanup level as one of its reasons for closing the refinery in May.

Cardona says the public is invited to sit in on the panel’s deliberations, but they must register before Monday.

Cardona says DEC will conduct a followup session on Sept. 17th for members of the public who have questions about the sulfolane-cleanup review.

“People can observe, and then after the meetings, there’ll be a Q&A session and then DEC will stay if people have questions. We’ll be there to answer them,” she said.

The panel will submit a report to DEC summarizing  its recommendations that the agency will consider as part of its final decision on the sulfolane cleanup level. DEC officials say the agency will issue that decision by the end of the year.

Editor’s Note: Members of the public may submit technical comments on sulfolane reference doses online to TERA. Comments must be received by September 8th.