Since November 27, 2013, the Alaska Department of Environmental Conservation (DEC) has been receiving public comments on Flint Hill Resources’ request to reduce its liability to clean up drinking water at its North Pole refinery that is seriously contaminated with sulfolane, an industrial solvent used in the production containing gasoline.

The DEC issued a “letter of conditional approval for revised human health risk assessment for the Flint Hills North Pole Refinery regarding the alternative cleanup level for sulfolane in local groundwater,” and a public notice allowing for comments. The deadline for public comment is February 10, 2014.

On February 5, Flint Hills Resources Alaska, a subsidiary of Koch Industries, announced that it would be closing its refinery this summer, laying off 80 employees, and leaving Alaska after contaminating the municipal water supply and water wells for more than 300 families. Company officials cited the cost of cleaning up the contaminated water as one reason for closing the refinery.

Last year, the Alaska DEC established a site-specific alternative cleanup level for sulfolane in groundwater of 14 parts per billion (ppb). DEC decided on that level using new toxicity data and on the advice of state and federal agencies.

But Flint Hills wants a lower alternative cleanup level of 362 ppb, leaving 348 ppb of contamination in Alaska’s waters. According to the DEC’s Contaminated Sites program, Alaskans should not drink water if it has over 25 ppb of sulfolane. “If your water well results showed above 25 parts per billion sulfolane, we advise you not drink the water,” cites a warning on its website.