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There are no groundwater wells within reasonable distance to the operation that are used as a source <br />of water. There are many test wells and piezometers that are being actively monitored on the FMM <br />property and these wells will be used by FMM and CDPHE to monitor the effects of gravel pit <br />pumping on petroleum hydrocarbons, free product and other contaminants that exist on the FMM <br />property. The main risk is that the pit pumping will draw down the plumes of hydrocarbons in the <br />northern part of the FMM property toward the gravel pit. The letter included in Appendix D from <br />the CDPHE to FMM dated September 24, 2002 shows that additional monitoring wells (MW-4 and <br />MW-5) must be installed prior to mining. Also, the CDPHE letter also shows that the site is divided <br />into three areas: Subareas 1,2 and 3. Subareas 1 and 3 are approved for mining at this time. Subarea <br />2 has old evaporation ponds from the old refinery operation that still contain some petroleum <br />products. These products must be cleaned up to the satisfaction of the CDPHE prior to any full <br />approval for mining in this area. The mining plan for this permit begins the mining phases in <br />Subarea 3. It is planned that the evaporation ponds will be cleaned up prior to the completion of <br />mining in Subarea 3 and the operation would simply continue in that direction (west) on the land in <br />Subarea 1 and 2. These Subareas are shown on Map C-2. <br />From prior groundwater sampling on the entire FMM property, it is also possible that benzene may <br />be encountered in the water being pumped from the pit. Previous testing showed levels ranging <br />from 1.5 to 19 parts per billion in the water samples of the permit area. It is planned that aeration <br />would be used to reduce any benzene levels to lower than 5 parts per billion prior to discharge. <br />All discharges from pumping water will be regulated under a combined storm water/process water <br />permit that has been applied for with the Colorado Department of Health. If the water quality is out <br />of compliance, water will not be discharged until it is in compliance. The gravel mining operation <br />would likely have to be suspended in this case. <br />Gilsonite Pi[ 10/02 27 <br />