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replaced on some of the regraded areas. With the more shallow topsoil <br />replacement depth proposed, the suspect levels for pH and electrical conductivity <br />become more important. Based on the proposed change in topsoil replacement <br />depth, the Division requests that Colowyo change the suspect levels for pH and <br />electrical conductivity. The Division requests that Colowyo change the pH <br />suspect level from "less than 5 and greater than 9 standard units" to "less than 5.5 <br />and greater than 8.8 standard units". The Division also requests that Colowyo <br />change the electrical conductivity suspect level from "greater than 12 <br />millimhos/cm" to "greater than 8.0 millimhos/cm". <br />Rule 2.04.7 - Hydrologic Description <br />7. In the probable hydrologic consequences section of the Colowyo permit there is no <br />discussion regarding spoil springs. Numerous spoil springs have been identified <br />by both aerial photographs and on the ground inspections in the East Pit. <br />Additionally, it is assumed that the continual discharge from the Streeter Pond, <br />even during the dry summer months, is a result of a spoil spring(s). Please include <br />a detailed discussion of the spoil springs that have developed in the East Pit as well <br />as those that are expected to develop in the West Pit and the South Taylor Pit. <br />Please include a discussion of the probable hydrologic consequences from these <br />spoil springs, including discussions on the anticipated changes in the quality and <br />quantity of surface and ground water. <br />Rule 3.02.2 - Determination of Bond Amount <br />8. Pursuant to Rule 3.02.2(4), Colowyo may provide the Division with a midterm <br />reclamation cost estimate for review and approval. The Division completed a <br />reclamation cost estimate with Permit Renewal 05 (approved 15 September 2009) <br />and determined that the amount of bond held was sufficient to cover the remaining <br />reclamation in the event of permit revocation and bond forfeiture. Since <br />equipment costs have not been updated since that time, the RN-05 estimate is still <br />valid. Colowyo did submit a reclamation cost estimate under the cover of <br />Technical Revision 85 but the Division deemed that revision incomplete on I <br />March 2010. The Colowyo estimate included changes to the mining and <br />reclamation plans that were proposed in Technical Revision 81 that have not yet <br />been approved. If Colowyo chooses to include a midterm review reclamation cost <br />estimate it should be for the currently approved reclamation plan. <br />Rule 4.05 - Hydrologic Balance <br />9. The Division and Colowyo have had many discussions over the last five plus years <br />regarding the long-term hydrologic stability of the Prospect watershed. While <br />these discussions have been mainly focused on the Prospect watershed, they are <br />equally applicable to the East Taylor and West Pit watersheds (for the West Pit) <br />and the Section 28 and West Taylor watersheds (for the South Taylor Pit). These <br />discussions have centered on controlling and slowing the runoff from the long, <br />Colowyo Mine <br />Permit No. C-1981-019 <br />2010 Midterm Review <br />10 May 2010 <br />10