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but not be limited to, the anticipated maximum size of each blast, approximate distances from the blast azea to active and abandoned underground mines, any required permits, certifications and record keeping, flyrock prevention safety measures for the public and for any livestock, the county road closure plan and county approval of the road closure, public warning signals and any required blasting notices. 11. In the Division's letter dated Mazch 30, 2007, a copy of Oxbow Mining's comment letter concerning TR-47 was mailed to BRL. In that letter, Oxbow commented that they did not want any changes or limits to their access to conduct mining operations due to proposed activities in TR-47. Considering that explosives will be used for the vent shaft construction, please comment on the possibility of TR-47 activities, including temporary road closures or flyrock hazazds, interfering with Oxbow Mining operations. Rule 4.03 -Roads 12. The Division's review of the haul road is not finished yet. When it is done, the Division will send any comments or questions to BRL. Rule 4.05.3 -Diversions and Conveyance of Overland Flow 13. On page Exh-8-213, the right sideslope ratio is listed as being 0.5:1 for ditch HC-Dl Steep. It appears that this should be 1.5:1. Please revise if this is the case. 14. In the vent shaft pad plan view on Map 39, the upland diversion subwatershed area is listed as being 12.9 acres in size. However, on Sedcad pages Exh-8-212 and Exh-8-218, the acreage used for the subwatershed is 12.0 acres. Please revise. Rule 4.05.6 -Sedimentation Ponds and Rule 4.05.9 -Impoundments 15. In the Elevation-Capacity-Discharge Table on page Exh-8-217, the peak stage is shown as being at an elevation of 6398 feet. This makes it appeaz that the 10 yr-24 hour event peak stage is right at the emergency spillway elevation. In the Detailed Dischazge Table on the same page, the full flow depth is listed as being at an elevation of 6398.25 feet. As written, this makes it appear that the ] 0 yr-24 hour event would flow out of the emergency spillway, which is prohibited in Rule 4.05.9(2)(b). In reality however, as shown on page Exh-8-219, the actual peak stage of the 10 yr-24 hour event plus sediment storage amounts to 0.118 acre feet or 5140 cubic feet, which corresponds to a pond elevation of about 6397.2 feet, which is below the emergency spillway elevation. Please explain these apparent discrepancies and revise for the sake of clarification.