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The applicant has proposed a groundwater monitoring program consisting of 15 monitoring locations, 9 onsite <br />and 6 offsite. The applicant has obtained 12 months of baseline data to date. Fluctuations of groundwater in the <br />surrounding azea greater than two feet below annual low levels will be used as a "trigger" for secondary <br />mitigation measures. Secondary mitigation measures include contacting neighboring well owners to discuss the <br />performance of their existing wells. If negative impacts aze indicated by a well owner then one of the following <br />measures will be implemented: <br />• Add a rechazge site on the Property neaz the affected azea; <br />• Re-drilUdeepen the affected well; <br />• Provide dewatering water to the affected party for direct use in irrigation at a rate equal to their decreed well <br />pumping rate <br />• Install a temporary water storage tank and pump system to deliver potable water to affected domestic wells <br />The northem injection well within the pernut boundary is in close proximity to the Landms domestic well and <br />will be used to mitigate any adverse impacts to water levels due to de-watering. Adverse impacts to water <br />quality of the Landrus well may be an issue. As a result, the Division has included a stipulation to the permit as <br />follows: <br />SBnufation No. 1 <br />Prior to exposure ofgroundwater or any pit de-watering, or installation of the underground recharge wells, <br />the applicant will obtain approval from the Division of Minerals and Geology of a water quality monitoring <br />and mitigation plan in the form of a revision to the permit. A copy of the revision shall be forwarded to the <br />objecting party (Georgia Landrus) when submitted to the Division of Minerals and Geology. The water <br />quality monitoring plan must include a plan for collection of baseline or ambient water quality samples, <br />sped the water quality parameters to be monitored, sped a point of compliance, spec fy the frequency of <br />monitoring and reporting to the Division, and specify a mitigation plan in the event of an exceedence of a <br />water quality parameter. <br />12. "Pazagraph (c) states that water from the dewatering operation will be diverted back to existing water <br />courses via existing right-of-way. Sheet 3, Mining Plan Map, shows a dischazge to the river and a dischazge <br />to the existing ROW from each of the two northern silt ponds. Subsequent discussions with Civil Resources <br />indicate that intended to use CDOT structures to move their water. I discussed this with CDOT Right of <br />Way Manager and the Maintenance Foreman for this azea and they indicated that they had no knowledge of <br />any easements or permits allowing this movement of water and that, based on policy, they doubted that any <br />such permission would be granted." (Colorado Department of Transportation; March 26, 2005) <br />Division of Minerals and Geology (DMG) Responses- The applicant provided documentation for the legal <br />tight to enter and use the Porter Seepage Ditch and Ogilvie Seepage Ditch. From the ditches, the applicant <br />proposes to dischazge water into two box culverts that run under Highway 85. The applicant stated the two <br />existing culverts associated with the site aze adequate to handle flows from pit dewatering and for water storage. <br />Historically, these culverts have been used for flow from tail water return ditches from the agricultural lands. <br />According to the applicant, the sources of return water have historically included groundwater from agricultural <br />wells and surface rights that were used to irrigate the crops. Farmers who benefit from seepage rights and other <br />water rights from the South Platte River have also traditionally used the culverts. <br />The culverts, identified on Sheet 3 of 7, are concrete box culverts with approximate dimensions 6' high by 8' <br />wide. According to CDOT, these "culverts" under US Hwy 85 are cattle crossings. The calculated dischazge, <br />assuming a zero percent slope, was 525 cfs (235,620 gpm) per culvert using only ten feet of the existing 15 feet <br />of headwater. The agricultural lands and surface irrigation will be replaced by the mine and dewatering <br />operations that is anticipated to dischazge a maximum of 20,000 gpm in total. The applicant proposes that the <br />mine dewatering be conveyed through the culverts in HDPE pipelines (or similar). The applicant has not <br />obtained written consent from CDOT to route mine water under US Hwy 85 via the box culverts. <br />In accordance with the foregoing discussion, the issue can be resolved by including the following stipulation <br />