Since 1999, Spectrum Engineering and Environmental, LLC (Spectrum), an HGL wholly owned subsidiary, has supported the Montana Department of Environmental Quality in the high-profile CERCLA remediation and reclamation of the Zortman and Landusky Mines. The 1,200-acre complex encompasses two open pit gold mines near the crest of the Little Rocky Mountains. The site received national attention in 1999 when the site operator declared bankruptcy and abandoned ongoing cleanup operations, leaving mining waste, cyanide leach pads, and mill sites to contaminate the only drinking water source for the Fort Belknap Indian Reservation.
Spectrum provides services to restore mine-impacted habitats and to evaluate ecosystems during remedial actions. To date, Spectrum has installed and vegetated over 1,250 acres of evapotranspiration (ET) cover systems and restored reclaimed areas as the decades-long remediation has progressed. The process has created an aesthetically pleasing, sustainable habitat using native grasses and trees to restore the site environments, stabilize slopes and prevent erosion, minimize infiltration through waste rock, and improve habitat. In addition, Spectrum has restored streambeds, armored streambanks, and restored sinuosity to minimize scour, and placed/graded 7.5 million cubic yards of fill to promote drainage. As part of its remediation efforts, HGL procured and installed a 250-kW wind turbine to augment treatment plant power requirements.