Project Profile: Mariscal Mine Potential Responsible Party Search, Big Bend National Park

Morning light at the Mariscal Mine.

NPS Photo / C. Hoyt

Bipartisan Infrastructure Law
Revegetation of Hazard Mine Lands | FY22 $29,000

The National Park Service will search for evidence to determine liability for contamination at Mariscal Mine in Big Bend National Park. Experts will match wastes found at the site with parties that may have contributed to the degradation and/or identify persons responsible for the release of hazardous substances at the site.

Why? Studies detected elevated mercury levels in soils, sediments, mine wastes, water, and air in and around the mine site. Mercury is identified as a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) hazardous substance. Under CERCLA, the NPS has the authority and responsibility to cleanup the site and seek reimbursement to the United States for associated costs. Determining liability is an important step for the National Park Service to pursue cost recovery for cleanup of the site.

What Else? The Mariscal Mine property is on the National Register of Historic Places. It is in a remote location, far from human habitation, but visited periodically by park staff and the public. Removing hazardous substances from the environment supports healthy ecosystems and the safety of visitors and staff.

Bipartisan Infrastructure Law – Ecosystem Restoration

This project was made possible by the Bipartisan Infrastructure Law – Ecosystem Restoration, signed on November 15, 2021. It is a historic investment in the restoration and protection of the environment.