The company responsible for one of the most environmentally contaminated sites ever in Maine must clean up the mercury and chemical waste that were dumped there, the state’s highest court ruled Thursday.

The Maine Supreme Judicial Court unanimously rejected an appeal by Mallinckrodt LLC, which is responsible for the former HoltraChem Manufacturing Co. plant on the Penobscot River in Orrington. The company sought a less expensive alternative to the estimated $130 million cleanup ordered by the state Department of Environmental Protection in 2010.

Mallinckrodt argued in its appeal that the state incorrectly treated the contamination as a legal “emergency” though it had existed for decades. The company sought to have a lower court’s ruling overturned so it could be allowed to complete a lesser remediation of the site, expected to cost about $100 million, according to the company.

“Contrary to Mallinckrodt’s argument, the plain language of (the state law) does not compel the conclusion that it applies only in the case of an emergency,” the court said in its 21-page decision, written by Justice Andrew Mead. “There is no dispute that hazardous materials have been handled on the site and that they are currently located there.”

St. Louis-based Mallinckrodt is a pharmaceutical company that inherited responsibility for the contaminated site after HoltraChem went bankrupt and dissolved in 2001.

The DEP ordered Mallinckrodt in 2008 to completely remove the contaminated soil from five landfills on the site, which would have cost about $250 million. The state revised that order in 2010 to require Mallinckrodt to remove the soil from only two of the landfills and cap the other three, at an estimated cost of $130 million. The Supreme Judicial Court upheld that 2010 order in its 6-0 ruling.

The chemical plant opened in 1967, using mercury in a process to create chemicals and dumping the waste directly into the Penobscot River. The river drains the second-largest watershed in New England and empties into Penobscot Bay.

The plant later deposited the waste in the five landfills, contaminating 77 acres of its 235-acre site.

Most of the buildings and 1 million pounds of contaminated soil have been removed, and a treatment system has been installed to extract mercury from the groundwater. The landfills have been secured since the plant stopped operating in 2000, according to Mallinckrodt.

Mallinckrodt contended in its appeal that the Maine Board of Environmental Protection overstepped its legal bounds in ordering the company to complete an extensive “dig-and-haul” operation. It pushed instead to spend $100 million beyond the $40 million it has already spent, according to arguments submitted to the court by one of Mallinckrodt’s attorneys, Jeffrey Talbert.

“The question before the court is not whether the former HoltraChem site needs to be cleaned up, or whether Mallinckrodt will clean it up,” said Talbert.

Assistant Attorney General Peter LaFond, who represented the DEP in the case, argued that Mallinckrodt’s contentions were unfounded and that a Superior Court ruling in 2010 upheld the Board of Environmental Protection’s final order that the company complete the more extensive cleanup.

“The Mallinckrodt site is one of the worst ongoing environmental disasters in the history of the state of Maine,” LaFond said in his written arguments. “While Mallinckrodt had voluntarily performed some limited remediation at the site over the years, it had refused to complete the remediation, except on its own inadequate terms.”

DEP Commissioner Patricia Aho said Thursday’s ruling validates the years of work her department has devoted to the cleanup of the former HoltraChem site.

“It is our hope that Mallinckrodt will stop using delay tactics through the court system and clean up the site,” Aho said in a prepared statement. “The department stands ready and willing to work with Mallinckrodt on the long overdue remediation so the site can be turned back into productive use.”

Talbert did not return a phone message seeking comment on Thursday’s decision, but a Mallinckrodt spokesman issued a statement.

“Mallinckrodt US LLC is currently reviewing the Law Court decision issued today regarding the clean-up of the former HoltraChem site. We are hopeful that we can move forward cooperatively with the Maine DEP to discuss how best to implement the Court’s decision,” said Mallinckrodt spokesman Ernie Corrigan.

The Maine People’s Alliance, a grass-roots group that has sought cleanup of the site for decades, applauded Thursday’s ruling as a partial victory, though it foresees a need to continue monitoring Mallinckrodt for years to come.

“This represents the end of the road for the company’s attempts to delay the cleanup of the mercury-contaminated site and shirk their responsibilities,” said Jesse Graham, the group’s executive director. “We hope thorough cleanup of the site will finally begin and we will continue to watch the progress.”

Graham said he has been involved in the fight to clean up the site since 1999, and members of his group have been involved in monitoring and registering complaints since the 1980s.

The Maine People’s Alliance and the Natural Resources Defense Council have also brought a federal lawsuit against Mallinckrodt, and it has been pending since 2000.

After one trial in the federal case, a judge ordered Mallinckrodt to fund a two-part, multimillion-dollar independent study to determine the feasibility of cleaning up mercury contamination downriver from Orrington.

A second trial is set to begin in June to determine the extent of the cleanup that Mallinckrodt could be ordered to do downriver and into Penobscot Bay.

Scott Dolan can be contacted at 791-6304 or at:

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