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30. Comment: The applicant proposes, via the January 28, 1997 RMC letter to Scott Gudahl, several methods for mitigation of water table impacts relating to mine dewatering and mine reclamation (slurry wall construction). For example, the RMC letter states "Where dewatering impacts wells, wetlands or swface featwes, the impacts can be mitigated by strategically applying dewatering discharge water or other available water back to the aquifer (recharge) via unlined ditches or infiltration galleries." And, later ... "The shadow effect will, however, impact wells on the south side of Hygiene Road between Foothills Reservoir and 61st Street. However, impacts to these wells can be mitigated by engineering an infiltration structwe on the south side of the pond and applying water from the pond or other sowces." The applicant should explicitly state which ground water mitigation methods will be employed for the various wells identified in the detailed hydrogeologic evaluation and where and how they will be employed, The applicant should also provide on a revised map the location of all ground water mitigation sttuctwes or methods to be employed. Response: The Division is referred to Attachment #8, "An Analysis of Possible Groundwater and Surface Water Impacts Resulting from the Lyons- , Rockin' WP Gravel Pit," prepared by Bishop Brogden Associates, Inc. 31. Comment: Rule 6.4.7(3) requires the applicant to provide an estimate ofthe project water requirements including flow rates, evaporative loss, annual volumes for development and mining and reclamation phases of ' operation. Please submit this information to the Division. Response: The Division is referred to Attachment #8, the document prepared by Bishop Brogden Associates, Inc., entitled "An Analysis of Possible f t R lti th L G d t d S W I fr roun wa ur ace esu om e yons- er an ater mpac s ng Rockin' WP Gravel Pit" regarding groundwater depletions associated r with this amendment. Furthermore, prior to the start of mining in the amended azea, WMI will obtain approval for a substitute supply plan from the State Engineer's Office. 32. Cotnment: The applicant notes 23 wells are permitted on or within 500 feet of the project (1/28/97 RMC letter). The applicant identified only 22 of the 23 wells on Exhibit O. Please locate the missing well on the exhibit. DMG Adequacy Review Response Page 13