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(Page 2) <br />MINE ID # OR PROSPECTING ID #: M-1983-067 <br />INSPECTION DATE: May 27, 2009 INSPECTOR'S INITIALS: _ DR? <br />OBSERVATIONS <br />The Division responded to written complaints regarding elevated ground water from seven citizens belonging to <br />the Zigan Homeowners Association, an organization of homeowners who live around the lake located northeast <br />of the intersection of 124" Avenue and Brighton Road in Adams County. The homeowners and the lake are <br />located directly east of and across Brighton Road from the Stagecoach Pit, operated by Albert Frei & Sons, Inc. <br />The citizen complaints included wet crawl spaces, inundated leach fields and septic tanks, submerged docks and <br />recreational equipment, and washed out beaches. <br />The citizens report that they first started noticing elevated ground water levels soon after installation of the slurry <br />wall at the Stagecoach Pit. Division records show that installation of the slurry wall began in October 2005 and <br />was completed in December 2005. Monitoring well data from MW-2 and MW-3, located immediately east of the <br />pit and close to the slurry wall, show a rise in ground water levels ranging from four to five feet immediately after <br />Lafarge began installing the slurry wall. These data and associated charts are attached. The Division met Ben Frei <br />of Albert Frei & Sons at the Stagecoach site on 20 May 2009 to explain the situation and to measure water levels <br />in two monitoring wells, MW-2 and MW-3. The level of ground water in the two monitoring wells was consistent <br />with and slightly elevated when compared with the most recently collected data. <br />Mining activity at the site has thus far been limited to stripping of topsoil and some overburden; actual excavation <br />of resource has not yet occurred. Albert Frei & Sons, Inc. only recently acquired the property from Lafarge West, <br />Inc. in a Succession of Operator that was finalized on 8 June 2009. <br />Based on the monitoring well data and the timing of the water table response immediately following installation of <br />the slurry wall, the Division believes that the slurry wall has created a barrier to ground water flow in the vicinity <br />and is responsible for the elevated levels of the lake and ground water around the homes of the area. If allowed to <br />progress unabated, this could cause an adverse impact to the prevailing hydrologic balance, and a violation of <br />§34-32.5-116(4)(h), C.R.S. for failure to minimize disturbances to the prevailing hydrologic balance. If not <br />mitigated, the disturbance to the prevailing hydrologic balance could also lead to a violation of §34-32.5-116(4)(i), <br />C.R.S. for failure to protect areas outside of the affected from slides or damage occurring during the mining <br />operation or reclamation. <br />It is the Division's conclusion that the slurry wall and subsequent mounding effect on the eastern, hydrologically <br />upgradient, side of the property constitutes a problem and hereby orders the Operator to implement mitigative <br />measures. DRMS has learned that the Operator, in consultation with the Zigan Homeowners Association, has <br />developed a proposal in which they will install a drain pipe to convey water from the lake to the South Platte <br />River and lower the level of both the lake and the ground water in the immediate vicinity. The Division also <br />understands that a short term plan is being proposed which will be to install a pump directly into the lake with <br />discharge to the South Platte River. This short-term plan will require the submittal, review, and approval of a <br />Technical Revision prior to implementation. The long-term plan will require an Amendment to the permit. <br />Operator should submit the Technical Revision within 30 days, and the Amendment with 60 days, of the date of <br />this inspection report.