2010-11-16_PERMIT FILE - C1996083A (22)

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2.04.7 Hydrology Description • The seasonal quantity and quality of the water within each aquifer is presented in Volume III, Exhibit 3 and on Maps 10A, 10B and 11. The Operator does not have down gradient baseline monitoring wells in the northeast section of the permit area because of technical difficulties. Ground water monitoring wells in the northeast portion of the permit area may be technically infeasible to implement because of extreme depth. In addition, it is technologically impracticable and extremely problematic to obtain representative water samples at depths that exceed 2,000 feet. To partially compensate for the lack of down gradient wells the Operator had HydroGeo, Inc. prepare a report that uses existing up gradient baseline data to predict down gradient water quality in the B -Seam and the water bearing zone above the B -Seam. The report provides expected ranges in values for pH, total dissolved solids, total Iron and total Manganese. HydroGeo's September 2, 2008 report is located in Volume III, Exhibit 3. 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 northeast 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 PR-12 2.04-31 - 06/10 A m6v6b