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Dan Mathews 4 June 8 2006 7. DMG - In January 2006, the Division received Technical Revision No. 20 for the Munger Canyon Mine, in which the operator is requesting approval to seal several of the alluvial wells that are not currently being monitored. Specifically the application requests sealing wells GW-2, GW-4, GW-7, and GW-8. The Division has reviewed the proposal in conjunction with this AHR review and concurs with the sealing of these wells with exception of GW-7. If access or right-of-entry is not an issue for GW-7, then the Division recommends that this well be retained forfuture monitoring. GW-7is located more than a mile down gradient of Munger Canyon and depending on the completion of this well, it mayserve as a groundwater point of compliance and be used for future bond release demonstrations. The Division concurs with permanent sealing of wells GW-2, GW-4, and G W-8 in accordance with Rule 4.07.3. CAM - As stated in response to Adequacy Review to Technical Revision 20, 'monitoring well GW-7 is located where the Operator once proposed a coal mine waste disposal area. G W-7 was first noted to contain water in 1987. The conductivity of the water was in excess of 100, 000 umhos/cm. Considering the wells high conductivity, it is not a candidate for groundwater point of compliance so it will be sealed. 8. DMG -During this AHR review records at the State Engineers Of£ce were reviewed. Three well permits were identified within a two mile radius of Munger and McClane Mines; one is located in Section 21 for the diversion of groundwater for the McClane Canyon Mine (permit no. 32752), permit no. 254049 was in Section 31 for a domestic use well that has since been abandoned, and permit no. 256862 is an existing alluvial well in Section 29 permitted for domestic use. As a result of this review the Division requests that Section 4.2.5 of the McClane permit be modified to include this information. Page 4-18 states that no wells are registered with the Colorado Division of Water Resources within two miles of the permit area. Please revise the water rights discussion on page 4-18 accordingly. DMG - On page 2-44 of the permit, it is stated, 'there are no adjudicated groundwater rights within more than two miles of the proposed permit area". The Division concurs, however this does not exclude the operator from groundwater quality protection. Since there is a domestic use well within relatively close proximity to the mining activity and located in the East Salt Creek alluvium, Domestic Use -Quality' classification of the Basic Standards For Ground Water may apply to the specified area of the mining activity and East Salt Creek alluvium. CAM -Updated page 4-18 to include the three groundwater wells in the water rights discussion. After locating groundwater well #256862 on the State Engineer's website, it was determined the well belongs to #11 Enterprises. This well is not being used for potable purposes, it is in a remote area, and there are no residential dwellings in the vicinity. The only'domestic' use possible for the well could be irrigation. The Division of Water Resources classifies a Domestic Well as able - `...to serve up to three single-familydwellings, irrigate one acre orless oflawn and garden and provide water for the individual's domestic animals and /ivesfocK'. Therefore, since the only use #11 may have for their well is irrigation, it is assumed there is not a domestic well used for potable purposes within a 2-mile radius. Amended pages 5, 6 and Table 5 from the 2005 AHR are enclosed. An application for a technical revision will follow this letter to incorporate the aforementioned amended pages, tables and figures into the permit. Please call if you have any questions. Sincerely, J. E Stov Consulting Engineer cc: Denver Office Enclosures