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As noted above, the Division is the implementing agency for groundwater protection at active mines. Ground water monitoring has not detected any elevated levels of selenium or pH. The rock formations adjacent to and beneath C-Pit have relatively low permeability. The bedding planes in these sedimentary rocks do not provide a hydraulic connection with the alluvial or Dakota Sandstone aquifer and permeability perpendicular to or across bedding planes is extremely low. The useable water supply is in the Dakota Formation which is 800-1,000 feet deep. In 1999, the applicant performed a study on the impact of a hypothetical leachate release on the deep Dakota Sandstone aquifer beneath the disposal site. Solute transport simulations were performed for selenium, thallium, total dissolved solids (TDS), pH and gross beta because they were the only constituents present in the leachate that exceeded water quality standazds. Results of the 2000 ground water analysis suggests that hypothetical CKD leachate release will not impact groundwater quality in either the St. Vrain Creek alluvium or the underlying Dakota Sandstone and do not cause the most stringent Colorado primary or secondary drinking water standazds or agricultural water quality standazds to be exceeded. The operator performed additional ground water studies in 2004 verifying that ground water will not be affected from water contained in the C-Pit. Monitoring of ground water in the Fort Hayes Limestone has not detected the elevated pH or selenium values. The operator has also complied with issues surrounding impacts to wildlife through the submittal of the Wildlife Assessment Report and increased the financial warranty to treat the water in the C-Pit in the event the site is abandoned. The long term plan is removal or burial of the water from the C-Pit and CEMEX has committed to removal or burial of the water in the C- Pit byMay of 2007. I hope that I have answered your questions and concerns regazding the water located in the C- Pit of the Lyons Quarry. If you wish to review the file in more detail, a copy of the imaged file is available upon request. Please see the attached form for further detail. If you have any questions, please do not hesitate to contact me at 303-866-4943. Si r ly, 1/ Erica S. rosby Environmental Protection ecialist cc: David Berry; DRMS Cazl Mount; DRMS David Bird; DRMS Steve Goodrich; CEMEX, Inc. Monica Sowders; CEMEX, Inc.