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• A resident or owner of a dwelling or structure that is located within one-half mile of the <br />location of the blast, as described in the annual blasting schedule, shall be notified no less <br />than 24 hours prior to any surface blasting or less frequently as each resident occupant in <br />such areas shall approve in writing to the Division. <br />Colowyo will regulate access into the area possibly subject to flyrock from blasting to protect <br />the public and livestock. Fences are in place to keep livestock out of the mining areas. The <br />permit area will be identified by signs on the access road restricting entry to authorized <br />personnel. Signs will also be posted identifying the area as a blasting area and describe the <br />warning and all-clear signals. Immediate access to the area of blasting will be cleared and <br />controlled by qualified mine personnel prior to any blast. <br />Colowyo will control air blast from its blasting operations within the permit area so it does <br />not exceed the values specified by the chart set forth in Rule 4.08.4(6). The same design <br />factors utilized to control the seismic effects of blasting (i.e.: the use of numerous surface <br />delays to "spread" the shots out over time, particularly near residences) is also very <br />effective in controlling airblast. Additionally, to keep airblast to a minimum Colowyo also <br />routinely 1) utilizes reduced weight (12 grain Zap) surface primer cord, 2) uses proper <br />stemming material, 3) uses a proper stemming weight, 4) avoids overdigging the front row <br />of holes and 5) avoids overloading the front row of holes. <br />Colowyo does perform event triggered monitoring. However, Colowyo will not commit to <br />daily monitoring due to unforeseen circumstances where the seismograph monitoring unit <br />may be getting repaired or calibrated. Colowyo employs an Instantel lnc. Minimate Plus <br />seismograph microphone with a low frequency limit of 2 Hz which corresponds to an <br />airblast standard of 133 dB (peak). Records of airblast monitoring will contain the <br />information required by Rule 4.08.5(17). This information will include either a recording <br />of the calibration signal of the monitoring instrument's gain setting at the time of each <br />blast, or certifications of the instrument's annual calibration. <br /> <br />4.08-5 Revision Date: 10/7/02 <br />Revision No.: RN-04 <br />