While mercury-contaminated soil is being removed from the former HoltraChem plant in Orrington, a former owner of the plant has long fought studying, let alone cleaning up, possible mercury contamination of the Penobscot River. The longer the mercury is in the river, the more it can spread through ecosystems stretching to Penobscot Bay. Studying the river now, more than four years after a federal court first ordered it to be done, could minimize the spread of damage and lessen the scope of any future cleanup efforts.

Late last month, a three-judge panel from the 1st Circuit Court of Appeals upheld a 2002 federal court ruling ordering Mallinckrodt Inc., which owned the plant from 1967 to 1982, to pay for an extensive study of possible mercury pollution downstream from the Orrington facility, which produced chlorine and other chemicals.

Mallinckrodt, the only former owner that is still in existence, argued against the District Court order on several fronts, a major contention being that the study’s costs – estimated at $4 million – would exceed its benefits.

The appeals court rejected this argument. “The plaintiffs established that the potential risk from mercury is serious and likely to be present here and now. In turn, these findings support a conclusion that, as the district court held, there may be an imminent and substantial endangerment to the lower Penobscot River. No more is exigible,” the judges wrote.

Mallinckrodt is considering whether to appeal to the entire 1st Circuit Court or to the U.S. Supreme Court.

The company is in the middle of a multiphase effort to clean up mercury at the former plant. Last August alone, crews removed another 1,800 pounds of mercury that had been stored at the site in addition to more than 1,400 pounds removed earlier last spring and summer.

Because tons of mercury ended up in the soil at the former HoltraChem facility, it is logical to assume the toxic metal ended up in the river, which is just down the bank from the plant. Other studies have found that mercury levels in the Penobscot are five times higher than in the Kennebec River, another waterway with industrial development along its banks. In the river, the mercury accumulates in fish and other wildlife. There is concern that it could contaminate shellfish and fish in Penobscot Bay.

As the court concluded, it is past time for the company to stop making excuses and to begin a study of mercury contamination of the Penobscot River.