Home  |  Contact Us  |  Profile  |  Client List  |  Personnel  |  News  |  Jobs  |  Publications |  Links

Our Expertise . . .

Backfill Projects

American Borate Company, Bille Mine, Death Valley, California, USA
   The Billie Mine utilized long-hole stoping with backfilling to extract borate. This mining method resulted in the creation of tall, narrow pillars which were critical to the stability of the mine. AAI was involved in the development of the mine plan and identification of the optimum pillar width. Pillar widths were selected by conducting computer simulations of stress analyses of the mine structure for different candidate pillar geometries. These analyses incorporated the effects of confining pressure, applied by the backfill, on pillar strength. Upon implementation of the mine design, an extensive geotechnical instrumentation program was used to evaluate the mine design and monitor overall stability.

Asamera Minerals (U.S.), Inc., Cannon Mine, Wenatchee, Washington, USA
   The Cannon Mine is a multi-lift benching cut-and-fill operation utilizing high-strength backfill to allow full recovery of the gold mineralization. AAI has been involved in the design of mining operations at the Cannon Mine since the development stage in 1982 through closure in the early 1990s. Geologic and rock mass characterization data was evaluated to provide design recommendations for bid specification on the construction of the access decline and shaft facility. Mine layout and stability evaluations were performed to develop recommendations for stope and pillar dimensions, and to specify the strength of cemented backfill. High-strength backfill was required for stable conditions during pillar recovery and to limit surface subsidence.  Production and backfilling sequences were established to coordinate the mine operations and optimize stability. Design of the backfill material included evaluating material resources, generating mixture specifications, and testing of different candidate mixtures. Different fill plant and emplacement systems were evaluated, with detailed cost estimates developed.  Subsidence was not permitted so the fill placement techniques were developed to minimize ground movement. Projects completed during mining and mine closure included monitoring ground movement, analysis of rock backfill interaction, and assessment of mine closure plans.

   Field personnel assisted Asamera geologists in structural characterization of drill core during the early exploration phases of the project. AAI personnel operated the Boyles Brothers wireline core orientation system to develop absolute orientation of structural features and shears during coring operations. The data, along with rock structural logging data, were used to develop recommendations for rock support systems required in construction of the main decline and shaft excavations.

• Mining Engineering

• Ventilation Engineering

• Highwall Mining

• Blasting & Explosives Eng.

• Solution Mining

• Rock Mechanics

• Rock Testing

• Stress Measurements

• Forensic Engineering

• Geology & Drilling Management

Project Summaries - Mineral

• Base Metals

• Coal

• Fertilizer Minerals

• Gold

• Limestone

• Oil Shale

• Trona

• Other

Project Summaries - Capability

• Block Caving

• Directional Drilling

• Forensics

• Geologic Studies

• Longwall

• Mine Reclamation

• Overcoring Stress Determinations

• Resource/Reserve Evaluation

• Slope Stability

• Solution Mining

• Subsidence

Abstracts

• Coal

• Hard Rock Mining

• Industrial Minerals

• Oil Shale

• Nuclear Waste

• Numerical Modeling

• Slope Stability

• Tunnels & Tunneling

• Ventilation