2008-08-20_PERMIT FILE - M2008006 (2)

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Mr. Peter Hays Re: SerFer Pit, Adequacy Letter Response August 15, 2008 Page 4 of 6 The groundwater elevation for the eastern monitoring well is expected to be approximately 4 -feet below the surface. During the installation of the monitoring wells, the depth to groundwater will be recorded and compared. to the estimated groundwater depths. If the estimated depth is observed to be significantly different than the estimated groundwater depth, the trigger points will be evaluated. It may be necessary to update the baseline groundwater level based on monitoring well- installation observation. In the event that the estimated groundwater levels are significantly different than observed groundwater levels, Connell Resources, Inc. will work with DRMS to establish an agreeable and reasonable groundwater baseline. Measured groundwater elevations in excess of two feet above or below the estimated baseline groundwater depths(see above) for three consecutive months will indicate that the mining or reclamation is impacting the groundwater regime and mitigation measures will be implemented (such as the construction of a perimeter drain). Connell Resources, Inc. will provide the DRMS with monthly monitoring well data on a quarterly basis, except in the. event that the monitoring wells show three consecutive months of exceedence of the two foot trigger in which case Connell Resources, Inc. will notify DRMS within 48 hours. If the three-month, two foot trigger is reached, Connell Resources, Inc. will work with DRMS to evaluate the cause of issue, and identify potential solutions or additional mitigation measures at that time. Connell Resources, Inc. will identify the additional mitigation measures or potential solutions within 15 working days after notifying DRMS of the exceedence. Connell Resources, Inc. will commit to investigating in response to claims of negative groundwater impacts from permitted well owners on adjacent properties. If this -investigation finds that the groundwater impacts are significant, Connell Resources, Inc. will work with DRMS to evaluate the cause of the issue and identify potential solutions or additional mitigation measures at that time. Connell Resources, Inc. will identify the additional mitigation measures or potential 'solutions within IS working days after notifying DRMS of the negative impact on neighboring groundwater wells. 8. The applicant states on page for of the SerFer Pit Groundwater monitoring Plan an action level will be determine and approved by DRMS. Typically, a trigger point of a,2 foot change form historic ground water levels is acceptable to the Division. Please commit to a 2 foot trigger point based on (5) quarters of ground water measurements. Connell Resources, Inc. will commit to the trigger points as determined in the proposed groundwater monitoring plan (see number 7 above). 9. Please specifically address the mitigation plan pertaining to the cottonwood trees located along the site. The USGS document Responses of Riparian Cottonwoods to Alluvial Water Table Declines states it.is evident that a drop in groundwater levels of one meter can be fatal to cottonwood trees. Please commit to a- two foot trigger point based on a five (5) quarters of groundwater measurements. The Division recommends installation of a settling pond adjacent to the cottonwood grove.