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Table 8. Results of 2010 Packer Testing Program
<br />Unit
<br />Number of
<br />Tests
<br />Hydraulic Conductivity (ft /day)
<br />Range
<br />Average
<br />Screened Interval
<br />Roof
<br />2
<br />1.10 to 1.46
<br />1.28
<br />Allen
<br />Coal
<br />3
<br />0.35 to 0.64
<br />0.51
<br />Water
<br />Floor
<br />2
<br />0.001 to 0.004
<br />0.003
<br />(ft elev. )
<br />Roof
<br />1
<br />0.002
<br />0.002
<br />Apache
<br />Coal
<br />3
<br />0.15 to 0.80
<br />0.48
<br />288.8
<br />Floor
<br />2
<br />1.10 to 1.46
<br />1.28
<br />7,370.9
<br />715.2 to 735.2
<br />Roof
<br />4
<br />0.001 to 0.04
<br />0.02
<br />Maxwell
<br />Coal
<br />5
<br />0.02 to 0.29
<br />0.013
<br />337.4
<br />Floor
<br />2
<br />0.04 to 0.10
<br />0.07
<br />Roof
<br />2
<br />0.02 to 1.06
<br />0.54
<br />Blue
<br />Coal
<br />3
<br />0.12 to 0.47
<br />0.43
<br />Floor
<br />3
<br />0.03 to 0.27
<br />0.11
<br />Coal
<br />8
<br />0.02 to 2.45
<br />0.43
<br />Other
<br />Sandstone
<br />3
<br />0.01 to 0.84
<br />0.31
<br />units
<br />Siltstone, Mudstone and
<br />Shale
<br />11
<br />0.001 to 0.11
<br />0.02
<br />Table 9. Completion Summary for 2010 Monitoring Wells
<br />Packer permeability tests indicate that the average hydraulic conductivities of the Allen,
<br />Apache, Red, Upper Bingham Canyon, Blue, Green, and Yellow coal seams are similar and
<br />range from 0.43 to 0.51 ft/day. The permeability of the Maxwell seam is lower with an average
<br />value of 0.013 ft/day. Clastic rocks including sandstone, siltstone, mudstone, and shale usually
<br />have lower permeability than the associated coals. Exceptions to this generalization include the
<br />interval between the Allen and Apache beds, which has an average hydraulic conductivity of
<br />1.28 ft/day, and the roof of the Blue coal seam, which has an average hydraulic conductivity of
<br />0.54 ft/day.
<br />Water level measurements during packer testing indicate that heads in the coal seams are
<br />lower than in the surrounding rocks. In many cases, the observed vertical gradients are
<br />exceptionally high and exceed unity. The high vertical gradients are related to groundwater
<br />pumping from the coal beds for coalbed methane (CBM) production. One hundred twenty -nine
<br />CBM wells are located within a one -mile radius of the permit area as of January, 2011. The
<br />presence of high vertical gradients indicates that permeability is low, perpendicular to bedding,
<br />and limits the flow of groundwater from the surrounding clastic rocks to the coal beds.
<br />Three bedrock monitoring wells were installed during the 2010 hydrologic investigation.
<br />Monitoring well NE -1 -10 is located near the northeast corner of the permit boundary and is
<br />completed in the Allen seam. Monitoring wells NE- 6 -10(a) and NE- 6 -10(b) are located near the
<br />northeast corner of the one -mile radius around the permit boundary and are completed in the
<br />TR -56 2.04 -18 Revised 2/1/11
<br />Monitored
<br />Northing
<br />Easting
<br />Top of
<br />Screened Interval
<br />Completion
<br />Depth to
<br />Well ID
<br />Unit
<br />(ft)
<br />(ft)
<br />Casing
<br />(ft bgs)
<br />Date
<br />Water
<br />(ft elev. )
<br />(ft btoc)
<br />NE -1 -10
<br />Allen
<br />1,179,572
<br />3,161,180
<br />7,334.3
<br />418.5 to 428.5
<br />9/13/10
<br />288.8
<br />NE- 6 -10(a)
<br />Apache
<br />1,183,658
<br />3,167,370
<br />7,370.9
<br />715.2 to 735.2
<br />11 /15 /10
<br />597.8
<br />NE- 6 -10(b)
<br />Blue
<br />1,183,658
<br />3,167,370
<br />7,370.6
<br />426.2 to 436.2
<br />11/16/10
<br />337.4
<br />Packer permeability tests indicate that the average hydraulic conductivities of the Allen,
<br />Apache, Red, Upper Bingham Canyon, Blue, Green, and Yellow coal seams are similar and
<br />range from 0.43 to 0.51 ft/day. The permeability of the Maxwell seam is lower with an average
<br />value of 0.013 ft/day. Clastic rocks including sandstone, siltstone, mudstone, and shale usually
<br />have lower permeability than the associated coals. Exceptions to this generalization include the
<br />interval between the Allen and Apache beds, which has an average hydraulic conductivity of
<br />1.28 ft/day, and the roof of the Blue coal seam, which has an average hydraulic conductivity of
<br />0.54 ft/day.
<br />Water level measurements during packer testing indicate that heads in the coal seams are
<br />lower than in the surrounding rocks. In many cases, the observed vertical gradients are
<br />exceptionally high and exceed unity. The high vertical gradients are related to groundwater
<br />pumping from the coal beds for coalbed methane (CBM) production. One hundred twenty -nine
<br />CBM wells are located within a one -mile radius of the permit area as of January, 2011. The
<br />presence of high vertical gradients indicates that permeability is low, perpendicular to bedding,
<br />and limits the flow of groundwater from the surrounding clastic rocks to the coal beds.
<br />Three bedrock monitoring wells were installed during the 2010 hydrologic investigation.
<br />Monitoring well NE -1 -10 is located near the northeast corner of the permit boundary and is
<br />completed in the Allen seam. Monitoring wells NE- 6 -10(a) and NE- 6 -10(b) are located near the
<br />northeast corner of the one -mile radius around the permit boundary and are completed in the
<br />TR -56 2.04 -18 Revised 2/1/11
<br />
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