Projects

Investigation, Remediation, and NPDES Compliance

The Mammoth Mine is part of a series of inactive copper mines located in steep terrain above Shasta Lake, adjacent to USFS land and in the Shasta-Trinity National Recreation Area. The mine was originally operated from the 1880s to the mid-1920s. The mine discharges acid rock drainage from portals, seeps, and waste rock dumps resulting in the degradation of Little Backbone Creek and numerous fish kills in Shasta Lake. The mine is currently operating under orders and NPDES requirements. VESTRA is working with the mine owner to meet the monitoring and remediation programs established by the RWQCB as well as coordinating the water quality monitoring, site remediation, and CWA compliance. As part of the site investigation phase of work, VETSRA installed a monitoring network using continuous recording technology to develop a basline data management tool which provides information to prioritize upcoming implementation of remedial activities. VESTRA has also prepared and submitted progress reports of detailed remedial activities, both quarterly and semi-annually. Ten bulkhead seals have been installed. Future work includes biological treatment and movement or capping of the largest waste rock dump in the area.