Tierra Group provided engineering and permitting support to Douglas County Public Works Engineering for NPDES Phase II Program compliance. Tierra Group’s scope of work included developing Runoff Control Plans (RCPs) for new County facilities, updating RCPs at existing County facilities, and reviewing, developing, and updating stormwater standard operating procedures (SOPs) for use at County facilities and projects.
Robinson Mine Tailings Impoundment Audit Prior to joining Tierra Group, our Team completed a third-party tailings impoundment audit. The audit included reviewing operational procedures, monitoring, design, and future tailings storage planning. Produced an audit report for company’s internal use. (Tetra Tech,…
Tierra Group participated as a member of a multi-disciplinary project team to develop a Definitive Feasibility study for a 16,000 tpd silver mine in Durango, Mexico. Tierra Group's responsibilities included designing a 112 Mt tailings storage facility, developing a site-wide…
Tierra Group completed an annual dam safety inspection (DSI) to meet both Nevada Division of Water Resources (NDWR) Dam Safety and the client's requirements. The DSI included reviewing monitoring data, a dam and appurtenant structures inspection, and a DSI report.
Tierra Group represented Oracle Ridge Mining as the Qualified Person for portions of the feasibility-level design including the Dry Stack Tailings Storage Facility (TSF) Design, Site-Wide Stormwater Management, Water Supply Pipelines, Haul Road and Access Road Design Improvements, and the…
Tierra Group was contracted by Waterton Global Mining Company to prepare the FPCP for TSF No.1 at the Esmeralda Mine. TSF No.1 covered approximately 100 acres, included a rockfill embankment with a maximum height approximately 60 feet, and stored gold tailings. Work…
Tierra Group updated the County’s Standard Operating Procedures (SOPs) for Municipal Operations to maintain the County’s compliance with the requirements for stormwater discharges from the County’s municipal separate storm sewer system (MS4) under the Colorado Discharge Permit System (CDPS). Tierra…
Dry Stack Tailings Storage Facility Tierra Group designed a dry stack TSF to store excess tailings from the underground paste backfill. The dry stack TSF was challenging, given the limited land area, steep terrain, seasonal cold weather, and surface water…
Tierra Group conducted geo-electrical testing to locate leaks present in the geomembrane liners underlying a Solution Conveyance Canal, Sumps 1 and 2, and the Intermediate Pond at Timmins Gold Corp’s San Francisco Mine in Sonora, Mexico. Leak detection testing procedures…
Newmarket Gold’s Cosmo Howley Project Area (CHPA) is a gold mine in the Northern Territory (NT), Australia. An underground mine is currently in operation with planned underground expansion. CHPA contains several legacy open pits, waste rock dumps, and surface water…
Tierra Group performed an independent engineering design review of a Cemented Tailings Facility (CTF) and multiple processes and freshwater ponds. Tailings will be mixed with cement at the paste plant and deposited in the CTF along with underground mine development…
Hydrogeologic Characterization Tierra Group provided hydrogeological support for data characterization and developed a conceptual and groundwater model to evaluate mine water inflows and the associated groundwater drawdown due to mine dewatering activities. Water Management Technical Review Tierra Group provided a…
Tierra Group advanced the TSF design to a Feasibility Level according to the Canadian National Instrument NI 43-101 and the U.S. Security and Exchange Commission’s Subpart SK-1300 regulation. Tierra Group’s scope of work included a geotechnical investigation, engineering analysis, and TSF…