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Nuvemco, LLC's Monogram Mine M-1978-222UG <br />Response to Preliminary Adequacy Review <br />March 10, 2009 <br />2) During the survey of underground workings, operator should document any standing water or inflowing <br />ground water observed, and discharge rates if they are treasurable. The findings should be reported to the <br />Division within 30 days of completion of work. <br />So noted, a report will be made to DRMS of any standing water or inflowing groundwater <br />discovered in surveys of underground workings. <br />3) Runoff from ore storage areas, if used for dust suppression, shall only be used for that purpose in the <br />immediate area of origin. The requirement should be expanded to include other areas. For example, page D- <br />2 discusses the use of pit runoff for dust suppression, Use of that runoff for dust suppression should be <br />limited to the area of origin as well, and should be contained inside the pit area runoff controls. <br />So noted, runoff from ore storage or mining runoff will only be used at the site of gathering for <br />dust suppression. <br />4) Regarding the statement on pg. D-3 "When all the sutface ore is removed the waste rock will be graded <br />across the disturbed area" the waste rock should be replaced only in areas tivhere it was originally removed, <br />not for instance, over disturbed areas such as roads or drill platforms peripheral to the pit area that did not <br />contain the waste rock previously. <br />So noted, waste rock will only be replaced in areas from which it was removed. <br />5) Pg. E-1, Exploration Drilling. 1) What is the proposed depth or range of depths for the drill holes? 2) The <br />drill hole abandonment plan should include a provision for abandonment of holes that, however unlikely, <br />encounter ground water. <br />As amended on page 5 of this response, drill holes are estimated to be from 200 to 400 feet deep. <br />In the event of drilling into a groundwater aquifer, and after consultation with DRMS, Nuvemco <br />may elect to construct an additional groundwater monitoring well for continued sampling within <br />the Monogram Permit area. <br />As stated in paragraph 3, page 5 of this response, all drill holes will be abandoned in accordance <br />with all regulations. In accordance with Colorado State Engineers Office rules, boreholes <br />penetrating aquifers will be sealed and abandoned by filling the well to the static water level with <br />drill cuttings, clean sand or clean gravel, then with clean native clays, cement or high solid <br />bentonite grout to the ground surface. <br />6) Appendix ), well construction and test report for well MMW2, the total depth is not shown in part 4, but <br />part 6 appears to indicate that the well was drilled to a TD of 210 ft, yet casing only extends to 168 ft. Please <br />explain. Was the hole backflled to 168? Also why was the bottom of the screened interval placed 42 ft above <br />the TD? What was the rationale for screening the well from 133-153 ft bgs? <br />The borehole was backfilled to 168 feet because, although dry, the significant potential aquifer <br />was the sand from 115 to 155 feet. The thin sandstone from 188 to 196 feet was dry and would <br />be penetrated by MMW1 on the lower bench. The thick sand interval was effectively covered by <br />screening from 133 to 153 feet and adding sand filter pack from 155 to 130 feet. <br />18