2010-02-24_REVISION - C1996083 (2)

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2.04.7 Hydrology Description • The USDA -FS controls surface access to any potential monitoring well sites. A few years ago the USDA -FS made a formal decision, with public input, to close Hubbard Creek road beyond the location of the DH -67 monitoring wells. Therefore, they strongly discourage re- opening Hubbard Creek road for access to a lower depth monitoring well site. The USDA -FS has approved one site (DH -68) on Iron Point as a potential monitoring well site. The location of DH -68 is shown on Map 9. Map 11 and Map 11 -1 present a prediction of the depth of the water bearing zone above the upper B -Seam. The depth to the water bearing zone is 2,350 -feet and the coal seam is 2,450 feet deep at DH -68. The extreme depth dictates two separate monitoring wells. A dual completion well would not be attempted at the required depth. One well would need to be installed in the formation above the B -Seam and one well in the B -Seam. The estimated cost to attempt to install the two wells is in excess of one million dollars. In late 2004, the Operator attempted to drill an exploratory hole from a location approximately 2,500 feet northwest of the approved site. Poor hole conditions were encountered immediately. As depth increased, the rock became more fractured and keeping the hole open became virtually impossible. At a depth of 2,612 feet the core bit was permanently stuck in the hole. All down hole assemblies were twisted off and cemented into the hole. The fractured rock is attributed to both the igneous Iron Point intrusion and depth of cover. Similar drilling conditions are expected at potential monitoring well site DH -68. The Operator does not believe it is economically or technically practicable to install down gradient monitoring wells north east of the proposed mine plan area. The rugged terrain limits potential drill sites. The only location where a reasonable depth monitoring well could be constructed is in Hubbard Creek but the UDSA -FS does not want the Hubbard Creek road re- opened. Opening the Hubbard Creek road would be problematic because of public opposition, road slope instability and potential flooding. It is highly unlikely the public will use the deep bedrock groundwater located north of the proposed mine plan area. It is simply too expensive to install a domestic or livestock well at such extreme depths. The poor water quality would also discourage public use. The lack of deep bedrock groundwater monitoring data is somewhat mitigated by the highly unlikely public use of the water. Based on the above discussion, the Operator requests relief from the installation of a down gradient monitoring well for the northeastern mining districts contemplated by PR -10, PR -11, and TR -65. PR -12 2.04-31- 02/10