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 an update of the Mexican Hat Project’s Preliminary Economic Assessment. Tierra Group’s update included the heap leach facility design and preliminary stacking plan, waste rock storage pad, and crushed rock storage pad design.
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…
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…
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,…
Tailings Management Assurance Review Tierra Group served as the Lead Auditor and conducted MARs for the TSFs at this confidential project. Tierra Group reviewed all available facility documentation, including OMS Manuals, EAPs, design reports, As-Built Reports, annual inspection reports, and other…
Tierra Group developed a water balance model to track flows into a backfilled pit at the closed Big Ledge Mine Barite Operation near Wells, Nevada. The Model was used to determine pipeline sizing to a remote treatment pond that is…
Nye-Hertzler Tailings Independent Review Panel (2020-2023) Tierra Group reviewed the TSF design to support an NI 43-101 compliant Feasibility Study. The TSF design incorporated a paste tailings disposal method in an environmentally sensitive fisheries habitat. Tierra Group sits on the Independent Review…
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 supervised a geotechnical and hydrogeologic drilling investigation program at Anglo American’s Quellaveco Mine in the Moquegua Region of Peru. Geotechnical Investigation Tierra Group developed a geotechnical and hydrogeological research plan within and near the Quellaveco Pit footprint. This…
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…
El Mochito is an underground zinc/silver mine located in the Santa Barbara Mountains in north-central Honduras. Tierra Group’s Team has been providing Tailings Stewardship Services at El Mochito continuously for the past 26 years. Since 1989, Tierra Group engineers have provided…
Tierra Group International, Ltd. participated as the geotechnical lead engineering firm for the Copperstone Project Pre-Feasibility Study (PFS) in Arizona, U.S.A. Tierra Group was responsible for tailings and waste rock storage, water management and underground geotechnics design and cost estimates…