PORTLAND, Maine — Maine Supreme Judicial Court justices on Tuesday questioned whether state environmental regulators were too disorganized in their handling of a longtime Orrington mercury polluter.

But in a Tuesday hearing on a case with decades-old roots, the judges also challenged claims by Mallinckrodt LLC, which ran the Penobscot River-front chemical plant from 1967 to 1982, that the Department of Environmental Protection’s approach to the case was unfair.

The now-closed HoltraChem factory produced 23,000 pounds of toxic mercury waste each year while developing chemicals for papermaking and other industries before the adoption of significant hazardous waste disposal regulations, according to court documents.

As the sole former owner of HoltraChem still in business, Mallinckrodt reports spending tens of millions of dollars over the years removing metallic mercury, mercury sludge and contaminated storage tanks and buildings from the site.

But the company has been locked in a legal and regulatory battle with the state since 2008, when DEP officials ordered Mallinckrodt to begin removing an estimated 360,000 tons of material in the five landfills.

Mallinckrodt argued that the so-called “dig-and-haul” remediation approach would cost the company as much as $250 million, compared to an alternative $40-million plan of encapsulating the contaminated materials on-site, which the company insisted would also be safer and more expedient.

Mallinckrodt appealed the 2008 order to the Board of Environmental Protection. That citizen board agreed in 2010 to modify some parts of the 2008 cleanup order, saying the company could leave three of the five landfills on-site after upgrading systems to prevent and detect pollution runoff into nearby groundwater sources.

Mallinckrodt subsequently appealed again, next to the Maine Supreme Judicial Court, which heard arguments in Portland late Tuesday morning.

Attorney Jeffrey Talbert, representing Mallinckrodt, told the high court justices Tuesday that the Board of Environmental Protection’s six-month appeal process did not follow any pre-established guidelines or procedures; included what amounted to expert testimony without adequate chances for the company to cross examine or respond; and allowed public outcry to bias the board despite scientific findings in Mallinckrodt’s favor.

Maine Supreme Judicial Court Justice Jon Levy asked Assistant Attorney General Peter LaFond, representing the DEP, about what the judge called “extensive ad hoc rulemaking throughout the [appeal] process.”

Justice Donald Alexander was among those on the court who on Tuesday questioned the influence of the public and state-selected scientists, who were asked to weigh in on the case.

“[The appeal process] doesn’t have to have what we’d technically call ‘cross examination,’ but there’s got to be some way to respond,” Alexander said.

But while the judges challenged what they described as a somewhat unstructured Board of Environmental Protection process, they didn’t appear entirely convinced that process inherently was unfair to Mallinckrodt.

“You were invited to weigh in at every step of the way,” Justice Andrew Mead told Talbert.

The left-leaning Maine People’s Alliance, which filed a brief in the case, was represented in court Tuesday by attorney Eric Mehnert, who argued that public input into the appeal process did not constitute the introduction of “political bias,” but rather was appropriate because state environmental laws are written, first and foremost, to protect Maine’s residents.

“Today we saw the latest attempt by Mallinckrodt LLC to delay the full cleanup of the site of the former HoltraChem plant in Orrington,” Jesse Graham, executive director of the Maine People’s Alliance, said in a Tuesday afternoon statement. “Thirteen years after the closure of the plant, this appeal represents the end of the road for the company’s attempts to delay the cleanup of the mercury-contaminated site and shirk their responsibilities. We hope the court rejects the appeal and a thorough cleanup of the site will finally begin.”

Seth has nearly a decade of professional journalism experience and writes about the greater Portland region.