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Work plan DRAFT <br />Due to the discontinuous nature of the strata of the Williams Fork, the lateral extent and <br />spatial continuity of the coal and interbed units is not clear at this time. Part of the <br />planned work includes developing a better understanding of the correlation and <br />continuity of these units. The F and G coal seams along with sandstone interbeds have <br />been identified as possible monitoring targets as discussed in Section 2.4. The <br />alluvium/colluvium of the various creeks represents another groundwater monitoring <br />target. Groundwater monitoring will be conducted to determine potentiometric levels <br />and water quality in the potential water-bearing units. Hydraulic information collected <br />during drilling along with single-hole hydraulic tests in monitoring wells will be used to <br />characterize hydraulic parameters. <br />Well construction diagrams which show typical monitoring well completion designs for <br />alluvium and bedrock wells are presented in Figures 3.1 and 3.2. Wells will be <br />constructed to meet relevant monitoring well construction requirements. It is anticipated <br />that direct rotary drilling techniques will be used to install all monitoring wells. Drilling <br />fluids will likely be limited to air, water, and foam. <br />Groundwater monitoring wells have been tentatively located on Plan 1 to provide <br />information both upgradient and downgradient of the operation while remaining outside <br />the proposed pit footprint. Table 3.1 summarizes the purpose of each monitoring <br />location, the strata being targeted, preliminary construction information, and the <br />sampling and analysis schedule. These targets are preliminary and may be adjusted as <br />additional drilling information becomes available. <br />There are four bedrock monitoring locations identified on Plan 1. Each location will be <br />evaluated for the installation of monitoring wells in one or more of the bedrock <br />monitoring targets. It is not clear at this time how far to the southwest these units will be <br />saturated, so some flexibility will be required in the final selection of the upgradient <br />bedrock monitoring locations. <br />Alluvial wells will be located upstream and downstream of the proposed operation on <br />each of the major drainages, including: Straight Gulch, Collom Gulch, and Jubb Creek. <br />In addition, a well will be located on Little Collom Gulch downstream from the valley fill <br />and above its confluence with Collom Gulch. An alluvial monitoring well already exists <br />on the lower portion of Jubb Creek so six new alluvial wells will be installed during this <br />field season. <br />Single-well aquifer tests will be conducted on each monitoring well to estimate formation <br />permeabilities. These tests will be performed after the well has been properly developed. <br />Estimates of permeability will be used to determine potential inflow rates to the mine. <br />Water quality samples will be collected from both bedrock and alluvial monitoring wells <br />on a quarterly schedule. Field parameters will be measured on a monthly schedule. <br />Table 3.2 lists the analytes and field parameters which will be reported for all <br />groundwater monitoring sites. <br />Dedicated sampling equipment such as submersible pumps, bailers, or sampling tubes <br />may be used to collect each sample. Stagnant water will be purged from each well prior <br />to collecting each sample. Field parameters, including pH, Electrical Conductivity (EC), <br />and temperature will be monitored during purging to document that all stagnant water <br />has been removed and representative groundwater is being sampled. The dissolved <br />metals fraction of each sample will be filtered in the field with a 0.45-micron filter. <br />2572-Rf Colowyo Coal Company, L. P. <br />Water Management Consultants <br />