Laserfiche WebLink
2801Youngfield Street, Suite 171 <br />~' ~ ~Mathesnn Golden, CO Soa01-2286 <br />ao3ra56-scss <br />~~ Mining Toll Flee 888-458-5638 <br />`'~ [tlonsultants inc. Fa" 30~~9 <br />~ www.mathesonmining.can <br />March 18, 2005 <br />Mr. John Hollenbectc <br />ACA Products <br />702 Gregg Drive <br />Buena Vista, CO 81211 <br />RE: Blast Vibration Monitoring, March 15, 2005. <br />Dear Mr. Hollenbeck, <br />Matheson Mining ConsuRarrts, Ina monitored one blast for ACA Products at their quarry southeast of Johnson's <br />Village, Colorado at 18:25:32 on Marsh 15, 2005. The seismograph was located on the west side of the dam <br />on bedrock apprwdmately 700 feet north of the dceest comer of the blast. The peak particle velocity measured <br />tram the blast was 0.02 inches per second and the peak air overpressure was 115.8dBL The measurement <br />was within the pennfi IimN of 2.0 inches per second arxi does not pose any potential hazard to the dam. <br />Attached to this letter are the vitiation record and the calibration certificates for the instrument, geophone and <br />microphone used to make the measuremert. Please contact our office should you have arty questions <br />concerning the attached or should you require additional irAonnation. <br />Sincerel'yJ, ~jy~ <br />Colin Matheson <br />President, Mining Engineer <br />