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S <br />Mr. Tom Kaldenbach <br />July 9, 2010 <br />Page 2 <br />of financial planning associated with this process, PSCM is considering whether to install the <br />additional bedrock wells further northwest of the existing wells CW23 and COV23 during 2010 <br />in order to collect adequate groundwater levels and water quality data for characterizing baseline <br />conditions. <br />Based on the :isotope data and water ages provided in the attached report, PSCM has measured <br />groundwater in the Wadge overburden and associated bedrock units (Wadge Coal and Wadge <br />Underburden) as ancient and over 1 million years old in the vicinity of all three bedrock wells, <br />and is likely of similar age or even older in these same units further and deeper to the northwest <br />within the synclinal basin. The isotope-derived age of the groundwater indicate movement in the <br />deeper portions of the Wadge overburden and Wadge Coal is minimal, and that assumptions used <br />to predict drawdown and pit inflows within the 5-year mine plan in the existing PSCM permit <br />application package are liberal at best. Based on the lack of connectivity indicated by the ground <br />water ages, drawdown and pit inflows due to mining in the vicinity of the Site 23 wells will likely <br />be lower than predicted. Potential impacts from any plans for future mining of the reserves to the <br />northwest should also be similar in magnitude and duration due to the apparent lack of connection <br />to shallow groundwater in these units closer to the outcrops. <br />Based on the enclosed report, PSCM believes the potential impacts of mining deeper reserves to <br />the northwest would be minimal based on the lack of connectivity to potential up-gradient sources <br />of recharge. Therefore, PSCM is requesting the Division consider our proposal to not install <br />additional bedrock wells further down-gradient within the mine permit area to the northwest. <br />Assumptions for groundwater levels and water quality in the Wadge Coal and Wadge overburden <br />further down-,gradient would be derived using data collected at the existing monitoring wells, and <br />impact assessments would take into account the lack of connectivity as a basis for calculating <br />potential impacts to deep bedrock units in these more distant areas. <br />I appreciate your time and effort reviewing the attached report, and would like to hear back from <br />the Division on our proposal to not install additional bedrock wells further down-gradient within <br />the PSCM permit area. Please don't hesitate to contact me via phone at 929.913.9218 or by email <br />at 'cochran )eabodyenergy com if you have any questions. <br />S' ce ely, / <br />J hn Cochran <br />anager Environmental Hydrology <br />Peabody Investments Corporation <br />C: Scott Cowman (PSCM) <br />Vern Pfannenstiel (PIC)