Contaminated Sites
HRA assists attorneys, agencies, and environmental and engineering firms with determining which entities should contribute to cleanup costs for contaminated sites. Our historical research into corporate ownership and succession, land ownership, methods and volumes of production, and sources of possible contamination plays a key role in identifying potentially responsible parties (PRPs).
Using corporate records, industry trade journals, title searches, aerial photographs, and archived and published production records, we trace the historical use of a site such as a uranium mine or a manufacturing plant, often in conjunction with the environmental restoration of the site and its surrounding area. We then produce well-researched reports, complete with graphics and maps, that are used to identify contributors to contamination and to bring additional parties into cost allocations.
HRA has conducted historical investigations of contaminated sites in Montana, Idaho, Washington, Utah, Texas, Alaska, Missouri, Kansas, Virginia, New York, and New Jersey.
Topics of research include:
- Subsurface and surface ownership
- Corporate ownership changes
- Operational and production history of mines, mills, and factories
- History of production methods
- Government role in wartime industry

Featured Members
Featured Projects
Bunker Hill Mining and Metallurgic Superfund Site
Contracted since 2010 to Coeur D’Alene Trust (Trust), HRA has been assisting the Environmental Protection Agency (EPA) in following its applicable or relevant and appropriate requirements in order to comply with the substance of Section 106 of the National Historic Preservation Act as regards its cleanup actions at the Bunker Hill Superfund Site (BHSS) in Northern Idaho’s Silver Valley.
Midnite Mine Superfund Litigation
HRA prepared an expert witness report and provided testimony at trial for a case involving cost recovery for cleanup of a former uranium mine.
North Cascades National Park
At the request of the National Park Service (NPS), HRA conducted research into the historical use and ownership of the two firing ranges in the North Cascades National Park Service Complex in Whatcom and Chelan Counties, Washington. The two ranges had been identified as hazardous waste sites due to lead contamination in the soil.
Salt Lake Valley Smelters
Working for a private client, HRA historians completed detailed research of local city, county and state records in Salt Lake City to identify the location and ownership of numerous historic smelter sites in the Salt Lake Valley.
Thea Foss Waterway
HRA historians researched the industrial development of the Thea Foss Waterway along the waterfront in Tacoma, Washington. The research focused on the history of dredging of the waterway by private interests and the U.S. Army Corps of Engineers.
Tri-State (Tar Creek) Superfund Site
HRA assisted clients with research on the Tri-State Mining District, a Superfund site in Kansas, Missouri, and Oklahoma where extensive lead mining activity occurred from the early 1900s to the 1980s. HRA’s work helped determine allocation of cleanup costs at the site.
Litigation Support
Expert Witness Services
HRA historians have served as expert witnesses in litigation, as well as providing research and writing support for outside experts.
Native American Issues
HRA historians offer extensive expertise in Native American history and legal issues, ranging from treaty rights to jurisdictional matters.