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F) Agreement of observed hydrologic impacts with the "Probable Hydrologic <br />Consequences" (PHC) projected in the mining permit <br />The PSCM PHC makes no predictions for impacts in the Fish Creek basin. However, the <br />predictions discussed previously in Section E (AVFs) are still valid for PSCM. The observed TDS <br />values are below the predicted values. The PSCM permit addresses potential impacts to surface <br />water quality in the Grassy Creek basin on pages 2.05-84 to 91 (Vol. 1A). A summary of those <br />impacts is presented on Table 2.05.6(3), page 2.05.89. This PHC focuses on impacts caused by <br />underground mine dewatering. As that scenario has not occurred yet, the PHC predictions are <br />not yet relevant. However, on page 2.05.88, it is stated "...Pond 002 is heavily affected by high- <br />TDS water from the Seneca II spoils aquifer, and averages nearly 4000 mg/1". In the five years of <br />data (2011-2015), the average TDS at Pond 002 (NPDES2) was 3936 mg/1. Further downstream <br />at Site YSGS, the average TDS for 2011-2015 was 2820 mg/1. The PHC makes no predictions <br />regarding the spoil springs themselves. <br />G) Completion of the Hydrologic Reclamation Plan <br />There are twenty monitor wells associated within or adjacent to the area being requested in the <br />PSCM Phase III bond release area. There are four spoil wells above Pond 004: SSP62, 63, 64 and <br />65. Well SSP62 is sampled for water quality; only water level data is being collected at the other <br />three. All four spoil wells will be removed after CDRMS approval of this bond release <br />application. <br />Two monitoring wells (SCAL46 and SCAL69) were constructed in the alluvium along Cow Camp <br />Creek downstream of Pond 004. Well SCAL46 was installed in 1981 a short distance below <br />Pond 004, and SCAL69 was installed in 1988. Both wells are small diameter PVC and are less <br />than 20 deep. Both water quality and water levels have been collected at both alluvial monitoring <br />wells since completion through 2016. <br />Three bedrock wells were constructed in approximately the same location during 1981 down- <br />slope from the active mining pit above Pond 004. They are: 1)Well SLO42 (102 feet deep, <br />completed in the Lennox overburden); 2)SOV42 (160 feet deep, completed in the <br />Lennox/Wadge interburden) and 3)SW42 (185 feet deep, completed in the Wadge Coal). Water <br />quality data was collected at both SW42 and SOV42 for several years only after completion. <br />35 <br />