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DMG believes that a qualitative analysis of the effects of groundwater depletion are unnecessary. In the 1993 U.S. Fish and Wildlife Service report, "The Response of a Mature Cottonwood Riparian Community to a Gradient of Alluvial Groundwater Decline," measurements taken at the Coal Creek Resources site specifically demonstrated that significant negative effects on the cottonwood groves can be proven when the groundwater table falls two feet below the average depth. Please commit to a specific course of mining changes which will be implemented when the depth of the water in the monitoring wells falls below this lower limit (7.5 below ground level), regardless of the apparent health of the cottonwood groves. The State Land Board set an upper limit of approximately 20~ mortality on the existing cottonwood community when they leased the property to the operator, and it is believed that waiting until negative effects are detectable may increase tree mortality beyond this agreed-upon limit. The in-place monitoring wells should be regarded as points of compliance for groundwater quantity. DMG would also like an up- to-date version of Figure D-2 with the new monitoring station trans.=_ct included, and a physical scale drawn on the map. Also, DMG feels that annual reports of the monitoring of the groundwater stations is inadequate, and would like TWK Enterprises to suggest a more frequent monitoring schedule. 3) DMG also wishes to inform TWK Enterprises at this time that unless the necessary compensation agreements are reached with the State Land Board, Public Service Co., and the Central Resources Gas Company with regard to mining within 200 feet of their permanent structures (roads and pipelines) DMG will only grant a conditional permit. Such a permit will state that no mining can take place until the legal issues and permission to mine are obtained from the intercasted parties which own the structures within 200 feet of the mining in writing, or an engineering study which proves that there will be no negative impacts from the mining on the structures. C.R.S.. 34-32.5-115-4(e) states that a permit can be denied on the grounds that "the mining operation will adversely affect the stability of any... permanent manmade structures located within 200 feet of the affected land; except the permit shall not be denied... where there is an agreement between the Operator and the persons having an interest in the structure... or where such an agreement can not be reached, the Applicant provides an appropriate engineering evaluation that demonstrates that such structures shall not be damaged by proposed.., operations." 4) Fie were unable to determine the nature of the strata which lies under the sand and gravel to be mined from the information given in the application. Please describe the nature of this layer, (including the thickness of the strata) so that DMG can decide if further soil amendments or topsoiling will be necessary after the material overlying these strata is removed. This is in accordance with Rule 6.4.4 (f)(ii) of the Construction Material Rules and Regulations.