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Hole Depth -Stem)"; however, Table 5 identifies " 3' Backfill" in the "Typical Powder Column" <br />diagram. As such, it appeazs that the first footnote on Figure 3 should state, "Open Hole Depth = <br />(Drilled Hole Depth -Backfill -Stem). <br />Please address this apparent discrepancy. <br />Item 14 Please also revise the "Blasting" section (beginning on page 2.05-28) and the "Use of <br />Explosives" section (beginning on page 4.08-1) to include something similar to the following: <br />"As shown in Tables 5, 5(A), and 6, overburden blast drill holes will typically be the only <br />type of blast drill holes that will contain bacltfill. If coal blast drill holes or overburden pre- <br />split blast drill holes contain bacltfdl, the depth of backtill will be denoted on a copy of <br />"Figure 2 Blasting Report". <br />Item 15 It appeazs that an error also exists with regazd to the second footnote of Figure 3. It <br />appeazs that the part that currently states, "(Open Hole Depth -Stem)" should read "(Open Hole <br />Depth)". <br />Please address this apparent discrepancy. <br />Item 16 Rule 4.08.5: A record of each blast, including seismograph reports, shall be retained for <br />at least three years and shall be available by the Division and by the public upon request. The <br />record shall contain the following data: <br />(17) Seismographic and airblast records, where required, including: <br />(18) Type of instrument, sensitivity, and the calibration signal of the gain setting or certification <br />of annual calibration; <br />(a) Exact location of instrument and the date, time and its distance from the <br />blast; <br />(b) Name of the person and firm taking the reading; <br />(c) Name of the person and frm analyzing the seismographic record; <br />(d) The vibration and/or airblast level recorded. <br />Colowyo's permit (pages 2.05-28 and 2.05-29) states "These blasting records, along with monthly <br />pit records (hazdcopy and electronic copy) can be used to compile all of the information necessary <br />to re-create the blast and contain the data necessary to comply with Rule 4.08.5." <br />Please revise this sentence to read, "These blasting records, along with monthly pit records <br />(hardcopy and electronic copy) and airblast records, can be used...". <br />Item 17 Colowyo's permit section "4.08.5 Records of Surface Blasting Activities" states, <br />"Seismograph records are not recorded due to the option that Colowyo has used the explosives <br />equation in 4,08.4(10)(b)(i)." This is an incorrect citation. <br />