2008-07-10_PERMIT FILE - M2008009

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Lyster Pit Page 4 of 5 Moffat County, Colorado July 3, 2008 b. For evaporative losses, the average number of acres of exposed water will need to tabulated each month. From this data, evaporative water losses can be calculated using the methodology outlined by the State Engineer's office. c. Additionally, if the State Engineer requires it for reasons of an augmentation plan, moisture content in the aggregates will need to be accounted for. This has been accounted for in the well permit. Monitoring of the groundwater regime can be done through monitoring the water surface elevation of groundwater surrounding the pit, and monitoring the water elevation in the adjacent Deep Cut Ditch, as well as the water elevation in the pit. As a minimum, it is always desirable to have at least three data points (groundwater observations) in a row in order to be able to determine drawdown trends, if any. A fourth point in the row is extremely helpful. To monitor the groundwater between the pit and the Deep Cut Ditch, we propose one well be place approximately 30 feet from the Ditch, and a second well be placed due north 150 feet, next to the property line. To the east, one well approximately 30 feet inside the property line, and a second roughly 100 feet east of the property line, should suffice. We anticipate the wells can be installed with a trackhoe, as the total depth doesn't need to be more than 12 to 15 feet deep. If at some point the water does drop below the reach of a trackhoe, a well drilling rig will need to be used to install the wells. We prefer 6" schedule 40 PVC pipe for backhoe monitoring wells (the larger pipe size doesn't break as readily when backfilling the test pits). If wells are drilled or augered, we recommend 2" I.D. Schedule 40 PVC. 3) Rule 6.4.4(c) discusses water flow. This is addressed in documents provided to the Division by the applicant. Water will generally flow north, towards the Yampa River. With respect to baseline monitoring, the proposed mining area is irrigated hay fields. We anticipate that seasonal fluctuations of the groundwater level are directly related to surface irrigation. Installing monitoring wells in mid-summer, and monitoring them through the fall will provide a reasonable understanding of how rapidly, or conversely, slowly, draining the soils are. As suggested by the Division, 5 quarters of monthly monitoring will bracket seasonal fluctuations of groundwater. However, the same information can usually be gained by excavating test pits to 10 to 15 feet deep, and monitoring either in the later winter to early summer months, or the summer months to the early winter months. Thus, we suggest that a six month monitoring period be implemented to determine seasonal fluctuations in the groundwater level. We anticipate that groundwater will be relatively shallow. SUMMARY AND RECOMMENDATIONS Based on a review of the 112 application packet, we believe the setbacks offered by the Applicant will more than provide adequate protection to the Deep Cut Ditch. Similarly, the WA-rF-R RESOURCE CONSULTANTS, LLC