The Maine Department of Environmental Protection filed a complaint Aug. 25 in Penobscot County Superior Court against Mallinckrodt US LLC (Mallinckrodt). The complaint details the failure by Mallinckrodt to complete cleanup of the former Holtrachem site located along the Penobscot River in Orrington, one of Maine’s most contaminated sites, according to a news release from the DEP.

The state said Mallinckrodt has not met remediation standards required in the DEP’s 2008 Designation of Uncontrolled Hazardous Substance Site and Order, that was affirmed in 2010 by the Board of Environmental Protection in its own slightly modified order, affirmed in 2012 by the Maine Business and Consumer Docket, and affirmed in 2014 by the Maine Supreme Judicial Court sitting as the Law Court.

The former Holtrachem site was a chloralkali manufacturing facility, which made chemicals commonly used in the pulp and paper industry.

Historic operations resulted in a significant amount of contamination, including highly toxic mercury and chloropicrin, in surrounding soils, groundwaters, and the Penobscot River. Site-specific standards were established by the DEP and BEP Orders to ensure that the site would be cleaned up in a manner that would protect public health, safety, and the environment.  Despite these Orders, large areas of soils still remain on site that exceed the site-specific cleanup standards.

"The DEP has worked diligently to provide oversight during cleanup of the former Holtrachem site to ensure that Mallinckrodt conducts remediation in compliance with the DEP and BEP Orders," the release said. "While progress has been made, it began to slow down as early as 2018 when Mallinckrodt began the first of several attempts to seek relief from meeting the Orders’ requirements. Since 2023, Mallinckrodt has ceased any meaningful progress toward remediation at the site."

Prior to today’s filing, two Notices of Violation (NOVs) were issued to Mallinckrodt on March 19, 2025, and October 22, 2025. These NOVs provide more detailed information about Mallinckrodt’s failure to comply with the DEP and BEP Orders. Copies of these NOVs are available on the DEP Mallinckrodt webpage.

The Department is seeking injunctive relief from the Penobscot Superior Court and civil penalties for ongoing violations.