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PERMIT #: M- 2002 -020 <br />INSPECTOR'S INITIALS: PSH <br />INSPECTION DATE: July 24, 2013 <br />The site was active during the inspection. Processed material was being removed from the site and a <br />processing plant was observed. The berms in the SE Pond have been constructed, dewatering of the SE Pond <br />has concluded and the northwest section of the pond is being backfilled to create an upland area. <br />The southwest mining cell was actively mining and dewatering during the inspection. Two dewatering pumps <br />were located in the northwest corner of the cell. The cell is dewatered with ditches and the water is pumped <br />into the ditch adjacent to 35th Avenue, which reports to the Cache La Poudre River north of the mine site. <br />The Division estimated the pit was thirty (30) feet in depth. Mr. Schenderlein stated there are no immediate <br />plans (within the next 5 years) to install the slurry wall around the mining cell. The slurry wall would isolate <br />the mining cell hydraulically from the groundwater table and may cause a mounding effect of groundwater to <br />the southwest. The mounding effect would restore and potentially increase the water table elevation in the <br />Rodman and the surrounding wells. Groundwater flow in the area is presumed to be to the northeast towards <br />the Cache La Poudre River. The timing of the installation could increase based on market demands for gravel. <br />Mr. Schenderlein stated the mitigation method for the three groundwater wells within 600 feet of the site is <br />completed. The City installed temporary water taps in June of 2013. The options of extending the City <br />waterline to the Rodman's was discussed, but would not be an immediate solution due to the time required to <br />plan and extend the waterline. The option of providing a cistern, which the Rodman's are agreeable too, as a <br />short-term solution and installing a deeper well (60 feet) for the Rodman's were discussed during the <br />inspection. <br />Mitigation <br />The approved Mining Impact Mitigation Plan for the site states if impacts are experienced due to mine <br />dewatering, these affects should be temporary and discontinue once dewatering operations cease or the <br />slurry wall is constructed. However, if dewatering from the amendment area directly affects the ability of <br />surrounding wells to pump a full supply of water in accordance with their permitted uses, the City of Greeley <br />will take all necessary actions to remedy the affects to the extent they were directly caused by operations at <br />the site. <br />Mitigation measures may include, but are not limited to: <br />1. Modify existing wells to operate under lower groundwater conditions. This would include re- drilling <br />existing wells to deeper depths or lowering the pumps. All work would be done at the City of Greeley's <br />expense with the exception of replacing equipment that was non - functional prior to mining. <br />2. If existing wells cannot be repaired, the applicant will drill a new well for the owner to replace the <br />damaged well. The new well will produce water of the same quantity and quality to support the <br />historic use. <br />3. Provide an alternative source of water to support the historic well water use during mine dewatering. <br />Since the Rodman's contacted the City regarding the impacts of the dewatering of the 25th Avenue site, the <br />following mitigation measures have occurred. The City cleaned and installed a new pump in the replacement <br />well (3597 -F -R) and installed a new pump in the newest well (055880 -F). Approximately two weeks before <br />this inspection the City linked both wells together in the pump house in an attempt to provide sufficient water <br />Page 3 of 7 <br />