American Borate Company 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 [...]
Project Summaries: Underground Mining
Instrumentation Installation The field work at the Kimballton Mine in Ripplemeade, Virginia, includes NX sample coring of the roof and floor of the 15E level of the mine, USBM-method overcore stress measurements, and installation of Geokon mupltiple-position borehole extensometers (MPBXs). An NX sample core hole was drilled through the ore zone and into the footwall [...]
West Ridge Resources, Inc. (WRRI) commissioned Agapito Associates, Inc. (AAI) to analyze subsidence potential from planned longwall mining in the vicinity of the Grassy Trail reservoir adjacent to the West Ridge Mine in Whitmore Canyon in 2004. The reservoir and earthen dam were constructed in the late 1950s and are a principal water source for [...]
Engineering Support for Start-up of Large Underground Coal Operation—Trinidad, Colorado Starting in 2009 and continuing into 2011, Agapito Associates, Inc. has provided most of the mining engineering services required to bring this large underground, multi-seam coal mining operation into production. At full production, the New Elk Coal Company mining complex is scheduled to produce over [...]
West Elk Mine—Somerset, CO AAI has provided underground geotechnical engineering services to Mountain Coal Company’s West Elk Mine since the 1980s. Services include installation of geotechnical instrumentation, in-situ stress measurements, laboratory rock properties testing, periodic ground control reviews, pillar and barrier sizing analysis, shield size specification, geotechnical characterization for shaft design, subsidence evaluation, and geological [...]
Longwall Optimization In 1997, AAI conducted three studies for West Ridge prior to mine development. The first study addressed longwall panel orientation based on local fracture mapping, conducted by AAI, and a review of local and regional geologic data. The second report dealt with preliminary gateroad design and pillar sizing. The third report described mine [...]
BHP Billiton AAI contracted to BHP Billiton to procure, install, and assist in monitoring the geotechnical instrumentation in and adjacent to the first longwall panel mined at the San Juan Mine. BHP Billiton provided the design of the instrument arrays to be used and worked closely with AAI engineers and technicians to establish the technical [...]
Canyon Fuel Company Longwall Mining—Shield Support Densities AAI has performed a full range of geotechnical analyses for SUFCO in support of their longwall operations, including pillar design, longwall shield support evaluations, and subsidence analyses. SUFCO currently mines with two-legged 970-T Joy shields in the Pines Tract (Upper Hiawatha Seam) under nominally 1,000 ft of cover. [...]
