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discharge from the formation water can have an impact on the ability of water to infiltrate <br />into the formation in any such areas. Accordingly, the study will require identification of <br />any such areas and an assessment of the potential for elevated gas pressures or gas <br />discharge to reduce or eliminate stream depletion where it otherwise might be occurring, <br />based on all other factors. <br />4. Basin Geologic Structure <br />5. Formation Outcrop Areas and Configuration <br />6. Spatial Variation in Lithologies or Characteristics Bearing on CBM Production <br />3. Characterize Regional Ground-water Flow Systems; <br />The hydrogeologic characteristics pertinent to the depletion analyses will be thoroughly assessed <br />for each differing hydrologic regime so that reliable depletion analyses can be carried out within <br />the basin. With respect to the aquifer characteristics noted below, it is required that, --assuming a <br />range of values is developed -- the values utilized in the actual depletion analyses runs, and <br />ultimately applied, will be assessed for reasonableness and appropriateness. In addition, there <br />will be required sensitivity analyses on each characteristic used in the analyses so that the level <br />of potential variation in the results can be understood. The work under this category will include <br />assessments, at a minimum, of the following items: <br />1. Identification of Regional Ground Water Flow Systems: <br />o Characterize Regional Ground Water Flow Systems; <br />o Identify Target Intervals to be De-watered in Relation to Regional Ground Water Flow <br />Systems; <br />o Identify Potential Flow Pathways Between Target Intervals and Aquifers or Tributary <br />Surface Water Systems; <br />o Rank Potential Flow Pathways according to Potential to Impact to Tributary Water Within <br />Regulatory Time Constraints. <br />2. Aquifer (or identified pathway) Characteristics: <br />o Hydraulic Conductivities; <br />o Saturated Thicknesses; <br />o Porosities and Specific Yield Values. <br />3. Aquifer Extent and Boundary Conditions: <br />o Lateral and Spatial Extent; <br />o Nature of the Boundary, e.g., Outcropping at Surface or Fault Truncated, Etc.; <br />o Discharge Areas (springs or streams gaining via formation contact); <br />o Recharge Areas. <br />4. Water-Level Conditions <br />o Confined/unconfined; <br />o Pre-CBM flow conditions; <br />o Surface Discharge: <br />¦ Location; <br />¦ Amount; <br />¦ Rate; <br />¦ Annual Volume. <br />4. Relate CBM Producing Formations to Local Ground-Water Resources; <br />The relationship between water production associated with CBM development and local ground- <br />water resources will be assessed. This entails establishing the three-dimensional relationship of <br />the target CBM stratigraphic intervals with those tapped by permitted water wells, both exempt <br />and non-exempt, are completed. The proximity of water wells to CBM production will be <br />assessed and water production rates evaluated for potential impacts to the permitted water wells. <br />The work under this category will include assessments, at a minimum, of the following items: