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of the specified blast design applies only if we conduct blasting within certain specified distances of those structures addressed in Rule 4.08.1(4)(a) and (b), or a) specified structures within 1000 feet or b)within 500 feet of an underground mine. Since Colowyo's blasting program does not meet either criteria, the cited Rule 4.08.1(4)(b) would not apply. Accordingly, we believe the information contained within the Permit already meets or exceeds the requirements for design information required of Colowyo and reflect the format requested and accepted by the Division in 1981 when the information was originally submitted. Nevertheless, Colowyo has reviewed the Division's request for more information and we submit the following comments for your consideration. Many of the proposed changes to the Permit are simply changes and/or updates to the way the information is presented and will not affect actual blasting activities. Item 2.1-Blast Desions Colowyo has revised the typical blast designs to clarify the information. Please see the attached revised Table 5 -Blasting Parameters -Overburden: Table 5(A) -Blasting Parameters -Overburden Pre-Split Shot and Table 6 -Blasting Parameters -Coal. Table 5 is also representative of the design for cast blasting shots, except more surface delays would be used. Individual blast specific conditions for hole depth, surface delay patterns, etc. would be reflected on the individual blast report. Due to the variable thicknesses of interburdens and coal seam thicknesses, the possible iterations and combinations for blasting are endless but not significantly different. We believe these modified typical designs, as presented, remain representative of the overall Colowyo blasting program. Item 2.2 -Powder Column -Tables 5. 5A and 6 The equivalent pounds of explosives is included in the revised Tables 5, 5A and 6 Item 2.3 -List of Residences See our response to Item 1 above. 11em 2.4 - Airblast In general, as noted in the Permit, Colowyo is located in an isolated, rural setting and our extensive land ownership position allows us to control the access to the mining area. As such, we are able to control the access of the Public and livestock into the mining areas. The location of the minesite alone serves as a significant "design factor" to assure that we protect the Public and comply with the applicable standards for airblast. The primary design factors utilized to control the ground vibration effects of blasting (ie: the use of numerous surface delays to "spread" the shots out over time, particularly near residences) is also very effective in controlling airblast. Additionally, to keep airblast to a minimum we also routinely 1) utilize reduced weight (12 grain Zap) surface primer cord, 2) use proper stemming material, 3) use a proper stemming height, 4) avoid over digging the front row of holes and 5) avoid overloading the front row of holes. The Permit section 4.08.4 has been modified to include this additional text. Item 2.5 - Flvrock Again, as noted in the Permit the isolated location of the minesite alone serves as a significant "design factor" to assure that Colowyo protects the Public and complie with the applicable standards for flyrock. As noted in the previous section the design factors utilized to control ground vibration and airblast will also insure that flyrock is controlled to protect the public and to meet the other