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Ebert <br />February 2, 2012 Page 2 <br />Based on the typical drawing for the alluvial well, the well construction is compromised (no <br />bentonite plug or cement surface seal). The placement of alluvial wells is also not ideal and very <br />little data is available for most of the alluvial wells due to apparently dry conditions. AW -1 through <br />AW -5 have been consistently dry (essentially no data provided). AW -3 has been mined through. <br />AW -4, 5, 6 and 7 are all placed in close proximity to each other about a mile northwest of the <br />permit boundary along Naturita Creek. There is some discussion in the PAP regarding the <br />placement of AW -4 through 6. There is sample data available for AW -6 and AW -7. <br />With regard to bedrock groundwater wells, the construction looks acceptable based on the <br />generalized typical schematic. I agree with the assessment that the mining operation is unlikely to <br />impact bedrock groundwater in the underlying Burro Canyon Formation. There is mudrock and <br />low penmeability beds below the coal mined from the Dakota isolating the underlying aquifer. I <br />have identified one significant issue regarding bedrock groundwater. The only well that is <br />downgradient from the pit disturbance location is (BW -2) and there is no data provided. Apparently <br />the well has been consistently dry whereas the other two bedrock wells located upgradient have <br />produced water and there is data available. The lack of water in BW -2 may be attributed to poor <br />monitoring well design and placement. However, the baseline data shows that the depth to water in <br />BW -2 was measured at 118 feet (total depth is 135 feet) in 4` quarter of 1990 but no sample was <br />collected. The other two bedrock wells are in somewhat odd locations both upgradient in line with <br />each other and off of the permit area to the east and south. There is good data for BW -1 (two years) <br />and two quarters of data for BW -3. <br />It's going to be difficult to make solid conclusions on potential impacts to alluvial and bedrock <br />groundwater given the lack of well construction details and data provided. It is also worth noting <br />here that the Water Monitoring Plan appears to have been revised with TR -7, specifically with <br />regard to bedrock wells a full suite sample has been removed from the monitoring schedule on page <br />2.03 -35 and only semi - annual water level measurements are now required since 1999. <br />The approved water monitoring plan identifies 6 springs to be surveyed in April or May and collect <br />a full suite analyses for springs with flow over 5gpm. With regard to Spoil Springs, the PAP <br />indicates no spoil springs are expected to occur. However, the Division independently assessed this <br />and predicts spoil spring development of 10.9 gpm to Section 33 Creek/Naturita Creek. I generally <br />agree with this conclusion but it is based on some assumptions from a study conducted at Seneca II <br />Mine in Routt County. DRMS will need to field survey the site at bond release inspection to <br />identify any spoil spring development. <br />I didn't identify any specific issues related to surface water. The surface water monitoring consists <br />of six locations including Bramiers Draw, Naturita Creek, Broad Creek, and Section 33 Creek and <br />calls for quarterly or semi - annual field parameters and annual full suite analyses. <br />I recommend the following course of action to rectify the problem regarding the operator's <br />noncompliance with the permit requirement to re- initiate water monitoring two years prior to <br />requesting final bond release. <br />