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Pre-law leachate vs. post-law leachate - Spoil springs that pre-date <br />SMCRA will hinder recognition of the hydrologic impacts <br />resulting from mining completed since the enactment of SMCRA <br />(PAP, page 2.5-104). <br />9. Duration of elevated dissolved solids in leachate -The elevated <br />dissolved solids will persist for a few hundred years (PAP, page <br />2.5-105). <br />Observed Impacts <br />Post-mining infiltration rate of meteoric water -Continuous spoil <br />spring flows totaling several hundred gpm indicate that meteroic <br />water is annually infiltrating into the approximately 119313 acres of <br />permitted disturbed ground surface (annual hydrology reports). <br />2. Spoil saturation -The formation of spoil springs indicates the <br />infiltrating meteoric water has saturated spoil in the toe <br />(northwestern, down-dip end) of each backfilled pit (annual <br />hydrology reports). <br />Spoil leachate quality -TDS has fluctuated around 3500 mg/1 in <br />the only spoil well, WR-1 (annual hydrology reports). <br />4. Dischazge of leachate from pit -TDS loading of Trout Creek <br />immediately downstream from the Edna Mine and the formation of <br />spoil springs indicate leachate is dischazging from pits at the mine <br />(PAP, page 2.SB-1 of Appendix 2.SB) <br />5. Leachate impacts on bedrock ground water -Mining operations <br />left a wedge of unmined bedrock less than 1,000 feet wide at the <br />toe of the pits that lies between the toe of the pits and Trout Creek. <br />This unmined rock is believed to transmit leachate from the <br />backfilled pits to the rock's outcrop next to Trout Creek and to its <br />subcrop beneath Trout Creek, resulting in the leachate flowing into <br />the creek's surface water and alluvium, rather than to bedrock <br />downdip from the creek. Consequently, no impacts to bedrock <br />ground water aze suspected. Substantial leachate dischazge to <br />bedrock in the bottom of Edna's pits would not be possible due to <br />the impermeable shale and siltstone that underlies the Wadge seam <br />as shown on lithologic and geophysical logs in Section 2.2.4.1 of <br />the PAP. The mining operation can be expected to be in <br />compliance with the basic standards for ground water for a <br />13 Revised from the 3,000 of the Renewal 4 Finding. See the 2005 Annual Reclamation <br />Report <br />C-1980-001 Permit Renewal 5 Findings Page 26 of 33 Pages <br />