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Marcia Talvitie <br />October 14, 2011 <br />Page 2 <br />N40 are representative of spoil water quality. No trend analysis regarding water quality or <br />water levels from GW -N40 were provided. Our review of GW -N40 water level data from <br />2001 onward show that the static water levels have remained fairly constant with an <br />occasional drop in water level. This further verifies that GW -N40 has not been impacted by <br />spoil water and is not representative of spoil water quality as presented by WFC in their <br />spoil water chemistry discussion. WFC is comparing GW -N40 (alluvial ground water) to <br />GW -N44 undisturbed overburden groundwater located to the northwest of the reclaimed <br />areas having a total depth of 60 feet with a slotted interval from 20.0 -60.0 feet. From this <br />water quality comparison shown in Table 5 page 22 WFC concludes that the presence of all <br />salts and TDS is lower in the spoil water and therefore the discussion regarding calcite <br />buffering is shown to be true. This is not a good analogy because the Division does not <br />concur that GW -N40 is representative of spoil water quality. <br />Please substantiate the statement that GW -N40 best represents spoil water and clarify <br />or validate the statement on page 20 that GW -N40 will show any changes in ground <br />water quality before any spring developed on the surface. <br />2. To verify the conclusion presented in C) Potential impacts of replaced spoil on <br />groundwater quality, please provide a more appropriate comparison of spoil water <br />quality versus undisturbed overburden water quality. Or provide a more detailed <br />analysis of affected groundwater by making direct comparison of baseline water <br />quality versus present water quality at upgradient and downgradient monitoring <br />locations in the overburden, coal, and if necessary underburden monitoring zones. <br />Please include an evaluation of any impact trends which may exist in the available <br />data. <br />Table 5 of the spoil water chemistry discussion shows GW -N44 as representative of <br />Underburden Water. The text describes it as an overburden well and the completion <br />information in the PAP also describes it as an overburden well. Also in Table 5 Iron <br />total is listed. Based on the data we have reviewed it appears that only dissolved iron <br />has been analyzed and reported for groundwater. Please clarify these discrepancies <br />and correct the table, if necessary. <br />Let me know if you have questions or require additional information. <br />C: Sandy Brown <br />DRMS Denver File <br />