Agapito Associates, Inc. (AAI) has the specialized personnel and equipment required for underground and surface drilling for instrumentation installation, resource confirmation, and exploration.
AAI’s equipment is designed for work in confined spaces and can be easily transported and assembled in difficult to access locations. Our drilling equipment is powered by either diesel, electric, or pneumatic motors so we are able to select the appropriate motor for the available power source or to meet MSHA requirements in “gassy” mines. Our drill rigs are capable of drilling any angle from vertical up to vertical down.
AAI’s field crew consists of experienced drillers with over 80 years of combined experience in coring and specialized drilling. Our experience base includes drilling holes for installation of instrumentation, overcoring for stress determination, coring for mechanical testing and rock quality, installation of ground monitoring and groundwater sampling and for geologic characterization. We have experience in coal, hard rock, and industrial mineral mines as well as embankment and concrete dams.
Drill rig specifications include:
- Ingetrol Explorer Jr. HP 75E (Specifications Sheet)—This core drill model is an electro-hydraulic drill with a Chuck “H” head with synchronization for underground work. This drill utilizes Load Sensing hydraulic technology. Its nominal depths with an “H” Chuck head are shown in the table at right.
- SD-1500 (Specifications Sheet)—This rig is either diesel- or electric-powered and can be set up on tracks or skids. This rig can be equipped with either surface or underground masts and winches.
- Boyle Super 300—This rig is powered either pneumatically or electrically and can be set up on tracks or skids. This drill rig is permissible in “gassy” mines when powered pneumatically.
- CP-65—This core drill is suitable for difficult access overcoring and is permissible for use in “gassy” mines.
AAI has specialized personnel and equipment required for diverse underground mining applications, including geotechnical and rock-mechanics drilling tasks. Since 1978, AAI has safely and successfully measured in situ stress in mines, tunnels, and concrete dams. Since 1994, our staff has completed over 800 overcore stress determinations.
Recent examples of stress measurement projects experience includes:
- Stillwater Mining Company, McLeod, Montana—In July of 2016, AAI conducted CSIRO HI Cell stress measurements on the 6500 Level of the East Boulder Mine.
- Leer Mining Complex, Leer Mine, Grafton, West Virginia—In December 2015, AAI completed two CSIRO HI Cell stress measurements and installed six CSIRO HI Cells for long-term monitoring for the U.S. National Institute for Occupational Safety and Health (NIOSH) on the #2 Panel ahead of the longwall retreat at the Leer Mine (underground coal). Two separate 50-ft roof and floor NQ2 core holes were also drilled.
- Sanford Underground Research Facility (SURF), at the former Homestake Mine, Lead, South Dakota—In 2014, AAI completed five CSIRO HI Cell stress measurements for SURF on the 4850 Level under the supervision of Jacobs Associates (Jacobs) located in Portland, Oregon.
- White Pine Mine, Michigan—In September 2013, AAI completed four CSIRO HI Cell stress measurements and approximately 150 ft of NQ2 coring (for RQD verification) for SubTerra LLC under the supervision of Barr Engineering, Inc. (Barr) located in Minneapolis, Minnesota, SubTerra’s geotechnical consultant. The stress measurements were made at the White Pine Copper Mine near White Pine, Michigan.
- Peabody Coal Mines, Colorado and Indiana—In 2010 and 2011, AAI was contracted by Southern Illinois University to complete two CSIRO HI Cell stress measurements at each of three Peabody Energy Corporation underground coal mines: Twentymile Coal near Hayden, Colorado, and the Air Quality and Francisco Mines located in southwestern Indiana.
- Resolution Copper Mine, Arizona—In 2010, AAI completed four CSIRO HI Cell stress measurements on the Neversweat Level (1,200-ft level) of the joint BHP Billiton-Rio Tinto Resolution Copper project near Superior, Arizona.
- USBM BDG at Roanoke Rapids Dam, North Carolina and Graymont Pleasant Gap Mine, Pennsylvania—In addition to the CSIRO stress measurement projects listed above, AAI also conducts stress measurements using the United States Bureau of Mines (USBM) borehole deformation gauge (BDG). In 2014, AAI completed nearly 80 USBM runs at Roanoke Rapids Dam in Roanoke Rapids, North Carolina for Dominion Power. AAI also measured stresses in three orthogonal boreholes to compute the complete stress tensor using USBM BDG methods at the Graymont Pleasant Gap Mine (underground limestone) near Pleasant Gap, Pennsylvania in the spring of 2014.
Underground Coring and Instrument Installation
AAI is highly experience with underground coring and geotechnical instrument installation. Typical core sizes range from BQ to HQ, (with other custom sizes available depending on application) and orientations from +90 to –90°. AAI’s trained crew and specialty drill rigs achieve the best possible recoveries in the most challenging formations from sedimentary to hard rock.
Recent examples of coring and instrumentation projects in 2015 include:
- Big Island Mine, Green River, Wyoming—In September through November 2015, AAI completed 34 bed-to-bed methane monitoring wells at the OCI (now Ciner Group) underground trona mine. Four continuous core holes were drilled with BQ drilling tools to verify lithology as the drilling campaign progressed. After drilling operations, 24 of the wells were fitted with pressure transducers and connected to a remote datalogging system.
- Edgar Experimental Mine, Colorado School of Mines (CSM), Idaho Springs, Colorado—In July of 2015, AAI completed approximately 90 ft of HQ coring and one CSIRO HI Cell overcoring run.
- Dugout Canyon, Skyline and Southern Utah Fuel Company (SUFCO) Mines, Central Utah—In multiple trips to these underground coal mines, AAI cored hundreds of feet of NQ core for resource delineation and other geotechnical tasks.
- Deer Creek Mine, Huntington, Utah—In February through June 2015, AAI completed approximately 60 bulkhead grouting holes, some of which were full face and others were cored. AAI also completed two 300+-ft vertical up holes from underground to surface. AAI drilled two holes from the portal to underground and reamed the holes to 6 inches. This was in support of Energy West’s mine closure effort at the Deer Creek Mine (underground coal).