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VIBRATECH® RECEI~/ED ' MAR 1 1 2004 March 1, 2004 w Division of Minerals and Geolegp AII2 OVERPRESSURE & GROUND VIBRATION STUDY FOR ' TRAPPER MINING, INC. TRAPPER MINE CRAIG, COLORADO PURPOSE ' The purpose of this study was to measure the ground vibration and air-borne effects from the blasting done at the Trapper Mining, Inc. location in Craig, Colorado from July 10, 2003 through October 14, 2003 (see comments on page 2 for interruptions in blast data monitoring at each ' location). The results were then compared to both the nationally accepted criteria and to the State of Colorado, Department of Minerals & Geology recommended levels. PROCEDURE Trapper Mining contracted Vibra-Tech Engineers, Ina (VTE) to perform a study to document the air overpressures and ground vibrations from the blasting activities within the mine. VTE placed three seismographs along the North and Northeast sides of the mine in order to monitor the blasting activity. Below is a list of the three monitoring locations: • Site #1 -"Davis Residence". An instrument and security box were set-up on July 10, 2003 approximately 100' South of the Southeast comer of the Davis residence, located off of Moffat County Road 35 and 5.7 miles from the intersection of US Highway 40 and Colorado Highway 13 at coordinates N 40° 27' 12" W 107° 30' 47". On October 15, 2003 the instrument and security box were removed. • Site #2 - °°Coy". An instrument and security box were set-up on July 10, 2003 at the end of Moffat County Road 35 inside the mine property line at coordinates N 40° 27' 24" W 107° 31' 31 ". On August 28, 2003 the instrument and security box were moved to site #3. • Site #3 - uNE Corner". An instrument and security box were set-up on August 28, 2003 at the Northeast comer of the mine property at coordinates N 40° 26' 13.5" W 107° 30' 18.8". On October 15, 2003 the instrument and security box were removed.