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 to a total depth of 137.8 feet. Another NX sample core hole was drilled into the roof of the mine to a depth of 11.4 feet. The core from both core holes was logged by CMC and the core was transported back to Grand Junction, Colorado, for sample selection and strength testing.
The first stress-measurement hole was drilled vertically down into the floor to a depth of 43.8 feet. Five USBM-method overcore stress measurements were successful in this hole. The second stress measurement hole was drilled horizontally to a depth of 49.8 feet. Six overcore runs were attempted and all were successful. Two Geokon two-anchor MPBXs were installed into pillars on the 12E level to monitor pillar separation in the horizontal plane.
