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.
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…
Tierra Group provided Tailings Stewardship Services for Continental Gold’s Buriticá Project in Antioquia, Columbia which included permitting support, Third-Party Review and construction and operations support. Tierra Group oversaw the development of a 2D hydrodynamic model to support the design of…
Sterling Mine is an underground gold mine in southern Nevada which recovers gold through heap leaching and a carbon adsorption-desorption-recovery (ADR) plant. Tierra Group team members have a long history at Sterling, starting with heap leach pad final permanent closure…
Engineer of Record Barrick’s Goldstrike Mine processes 30,000 tons of gold ore per day from its combined open-pit/underground operations located in the historic Carlin Trend in Nevada, U.S.A. Goldstrike’s tailings are stored in the North Block Tailings Disposal Facility (NBTDF).…
Lode-Star Gold, Inc., in advance of their proposed mining operations, submited a Physical Separation Facility application with the State of Nevada for their Goldfield Bonanza Project located in Esmeralda County, Nevada. The mine, located in the historic high-grade gold-bearing district of…
The Aurora Mine Mill Facility (previously Esmeralda Mill) is located in the historic Aurora mining district of the eastern Sierra Nevada Mountain Range in Nevada, USA. Aurora recently, with the support of Tierra Group completed a Minor Modification to the…
The Midas Mine is located in northern Nevada, and is owned and operated by Hecla Mining Company. The mine is an underground mine with an operating mill. The mine’s existing tailings facilities are nearing their end of operating life and…
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…
Tierra Group performed a technical peer review of the Isabella Pearl heap leach facility (HLF) owned by Gold Resource Corporation. Isabella Pearl mine is located at the west end of the Santa Fe mining district in the Walker Lane gold…
Tierra Group designed the Bunker Hill dry stack TSF. The TSF design was challenging given the limited land area, steep terrain, seasonal cold weather, and surface water management. Tierra Group’s scope of work included siting the facilities, geotechnical investigations, civil…
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 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…