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Require- ' ment Require- complied Requirement ment with ? (yes Comment citation I no/indeterm -inate Q. Content of CDMG pond reports regulation yes 4.05.6 13 The monitoring plan on permit page 5-36 calls for sampling 3 wells semiannually for both field parameters and full suite R. Sampling Page 5-36 analysis. One of the three wells (94-1) was backfilled and frequency of of CDMG reclaimed in 2002 during reclamation of the South Pit. The two ground water mining yes remaining wells are located upgradient and downgradient of the monitoring permit C- mine; sampling frequencies in these two wells were met in 2003. wells 92-080 Reclamimed well 94-I was within the mine, and its elimination will not significantly hinder the identification of trends in ground water quality and flow. The permit application should be revised via a TR to reflect the reclamation of we1194-1. S. Para- meters page 5-36 to be of CDMG analyze For the samples collected, all required parameters were d in mining Yes analyzed. ground Permit C- 92-080 water sam les Should any degradation occur, the following two aquifers are the most likely to be degraded by mining at Carbon Junction: the Animas River alluvium (400 ft. downslope from the mine) and the Pictured Cliffs Sandstone (subcrops beneath the mine pit). Alluvial aquifers; Animas River alluvial water can be expected to have not been degraded by mining because the less than 50- CWQCC acre surface area of spoil at the mine would not generate enough T. Basic regulation leachate to overcome the dilutional effect of native alluvial Standards ground water. for Ground s 41.4 and yes Bedrock aquifers: Downgradient monitoring well 95-1 was Water 41 5 drilled in i/94 to total depth 350 ft. Although its perforated depths are unavailable, presumably it was perforated like reclaimed well 94-1 i.e. top to bottom. The presumed perforated interval of well 95-1 extends through sandstone beds in the Fruitland formation and the Pictured Cliffs sandstone. The well is within the expected flowpath of any coal spoil leachate that would be generated in the Carbon Junction backfilled pits. Well 95-1 has not shown evidence of leachate. U. Restoration of ground water CDMG Carbon Junction's approximate 100-acre surface disturbance recharge to regulation yes probably is not enough to diminish recharge to aquifers. approximate 4.05.11(3) premining rate Page 3