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boundaries. The Division believes that the possibility exists for such contamination and requests that the operator gather pre-mining baseline hydrologic information and hydrologic monitoring data during mining operations for the AVF. j 16. The Division has no further concerns. BRL submitted the referenced table in Volume III, Exhibit 3 and a revised page 2.04-26. /17. Concerning the potential negative impacts to streams, BRL noted that Terror Creek and Hubbard Creek are outside the zone of potential subsidence. Concerning the potential negative impacts to springs, the operator stated that a mitigation plan for springs is contained in Exhibit 15 of Volume III. However, this plan seems to involve those springs damaged only by subsidence. Streams and springs may be damaged inside and outside the permit area by the drawdown of ground water due to mine water pumpage. Please add to page 2.04-37 that mining could impact streams, springs and ponds, whether inside or outside the permit area, and that BRL will mitigate such impacts. 29. The Division has no further concerns. In order to control erosion at the outlets to those culverts draining into ephemeral drainages, the operator will extend the culverts to the bottom of the ephemeral drainages. BRL revised Map 21-2 to show these extensions. Also, BRL stated that if the culvert extensions do not control erosion, then other methods will be employed, on a case by case basis. ~30. The Division has no further concerns. BRL determined the 25 year-24 hour precipitation amount of 2.0 inches from the SCS publication dated March 1984. The Division had used the 1973 NOAA Atlas in deriving a slightly higher value of 2.2 inches. 31. The Division has no further concerns. BRL has supplied revised pages Exh-8-3, Exh-8-12, Exh-8-13 and Exh-8-21. The revised pages account for changing the curve number for the burned / area to 81. 32. The Division has no further concerns. BRL revised page Exh-B- 5. For the pond B drainage, the direct runoff for the sagebrush area was increased slightly, but the runoff volume increase was negligible. / 33. The operator is designating the material storage area as a small area exemption (SAE). Revised page 2.05-32 describes the SAE design. Page Exh-8-14 is mentioned as a revised page as well but that page does not seem to concern the material storage area. Has that page, or another page, been revised? Finally, the Division believes that, as part of the design, the area being designated as an SAE should be located on an 2