EA is supporting mine rehabilitation, geochemical investigation, and remediation to decrease acid mine drainage (AMD) from reaching the Trinity River at this inactive copper, zinc, and gold mine. Our team designed a cantilever access/utility platform for access, mapped the underground workings, and conducted investigations of AMD in and around the adit. EA currently has a subcontractor determining water infiltration rates from collapsed stopes and winzes near the surface approximately 500 feet above the mine adit located in rugged mountain terrain.

EA is conducting an RI/FS to evaluate groundwater, surface water, soil, and sediment contamination from historical mining at an abandoned gold and silver hardrock mine, including a screening level PFAS assessment. It is believed contamination is primarily sourced from processing ponds, mining equipment, waste repositories, and a failing cyanide heap leach pad. ngoing multi‑phase field investigations—including environmental sampling, electromagnetic surveys, geophysical and hydraulic testing, macroinvertebrate and habitat bioassessments, and tracer studies—are supporting risk evaluation, nature and extent, and development of remedial alternatives.

EA operated and maintained the interim water treatment plant, which was constructed to control ongoing releases of metal-laden water from the Gold King Mine. Tasks included performing site operational monitoring and sampling, sludge management, pond maintenance, and seasonal cleaning of the conveyance systems.

Since 2018, EA has supported the remediation of the approximately 700-acre site that encompasses a former open pit mine, wetlands, and two residential communities. EA provides remedial investigation, pre-design investigation, contaminant flux modeling, engineering evaluation and cost analyses, risk assessment, community relations support, cultural resource and biological protection support, ROD, and remedial design and construction oversight services.

EA is supporting the New Mexico Environment Department with implementation of a new initiative to clean up abandoned uranium mines. The work involves site characterization and remedial design at two sites, the Schmitt Decline and Red Point
mines, as well as stakeholder engagement and public relations for the entire program.

EA conducted an RI/FS for a 340-acre site and the accompanying abandoned smelter. Tasks included extensive environmental
sampling and analysis, human health and ecological risk assessments, characterization of mine tailings and groundwater impacts, and associated contaminant transport. EA developed remedial alternatives, which included stabilization design for the tailings and provided agency coordination and community involvement.