Tierra Group realizó un diseño para el recrecimiento del terraplén de relaves Brushy Creek de Doe Run, una obra que fue inicialmente puesta en marcha en 1973. Para el diseño del terraplén se llevaron a cabo ensayos de penetración de cono, análisis de licuefacción, y modelados de filtraciones y de estabilidad de taludes. Aspectos tales como la hidrología, el diseño del vertedero y el trazado de la cubeta presentaron desafíos para el diseño debido a los límites de la propiedad y a la infraestructura existente. Los ingenieros de Tierra Group pudieron maximizar la capacidad de almacenamiento y minimizar los impactos operativos. Se entregará al Departamento de Seguridad de Presas de Missouri un informe de diseño y los protocolos de funcionamiento.
Tierra Group is assisting Millcreek Mining and Black Mountain Sand with the preparation of permitting documents for the Lost Creek Project; including a preliminary Stormwater Management Plan, preliminary Groundwater Monitoring Plan, and general permitting exhibits. Tierra Group conducted a site geotechnical…
Dam Breach Analyses Tierra Group prepared a DBA to evaluate potential downstream impacts due to a hypothetical failure (breach) in three components of Empire State Mines (ESM) tailings storage facility (TSF): North Dam (ND), South Dam (SD), and West Perimeter…
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,…
2023 Dam Inspections/Review Tierra Group completed a site visit to inspect three tailings storage facilities (TSFs) and the Evaporation Pond. In addition to the site visit and dam inspections, design and monitoring reports (prepared by others) were reviewed for each…
American Gypsum Pit Planning and Support Tierra Group began working at American Gypsum’s Eagle-Gypsum mine located in Gypsum, Colorado in 2014 evaluating haul road improvements. A trade-off study provided a tool for American Gypsum to evaluate safety improvements including alternative haul road…
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 completed a geotechnical investigation, which included overseeing hollow stem auger (HSA) drilling and laboratory testing, that characterized the existing earthen dam. Tierra Group completed a low-level outlet structure design that was believed to have been compromised by internal…
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…
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 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 Hazard and Operability review (HAZOP) for the new Cobalt Pilot Pant located at the Madison Mine facility in Missouri.
Tierra Group provided design review and technical direction at Hod Mine in the Artvin Province of Turkey. Work included detailed design of potentially acid generating and non-acid generating waste dump facilities, their appurtenant structures and stormwater management design for the…
Tierra Group is assisting Millcreek Mining and Black Mountain Sand with the preparation of permitting documents for the Lost Creek Project; including a preliminary Stormwater Management Plan, preliminary Groundwater Monitoring Plan, and general permitting exhibits. Tierra Group conducted a site geotechnical…
Dam Breach Analyses Tierra Group prepared a DBA to evaluate potential downstream impacts due to a hypothetical failure (breach) in three components of Empire State Mines (ESM) tailings storage facility (TSF): North Dam (ND), South Dam (SD), and West Perimeter…
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,…
2023 Dam Inspections/Review Tierra Group completed a site visit to inspect three tailings storage facilities (TSFs) and the Evaporation Pond. In addition to the site visit and dam inspections, design and monitoring reports (prepared by others) were reviewed for each…
American Gypsum Pit Planning and Support Tierra Group began working at American Gypsum’s Eagle-Gypsum mine located in Gypsum, Colorado in 2014 evaluating haul road improvements. A trade-off study provided a tool for American Gypsum to evaluate safety improvements including alternative haul road…
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 completed a geotechnical investigation, which included overseeing hollow stem auger (HSA) drilling and laboratory testing, that characterized the existing earthen dam. Tierra Group completed a low-level outlet structure design that was believed to have been compromised by internal…
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…
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 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 Hazard and Operability review (HAZOP) for the new Cobalt Pilot Pant located at the Madison Mine facility in Missouri.
Tierra Group provided design review and technical direction at Hod Mine in the Artvin Province of Turkey. Work included detailed design of potentially acid generating and non-acid generating waste dump facilities, their appurtenant structures and stormwater management design for the…
Tierra Group is assisting Millcreek Mining and Black Mountain Sand with the preparation of permitting documents for the Lost Creek Project; including a preliminary Stormwater Management Plan, preliminary Groundwater Monitoring Plan, and general permitting exhibits. Tierra Group conducted a site geotechnical…