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Page 2 of <br />Scott Wanstedt <br />11/20/2018 <br />The total incidental inflow of water into the mine was 8.21 gpm in the 2017 water <br />year. The value is in the predicted range of 5 to 10 gpm. In May of 2012 a <br />dewatering pump system was installed to pump excess water captured in the <br />underground mine to the surface. Water pumped to the surface from the B Seam <br />in the 2016- 2017 water year was 18,656,488 gallons or 35.5 gpm. Water was not <br />pumped from the SDH -315 D -Seam Dewatering System during the reporting <br />period. <br />Predicted by the PHC, Monitoring wells in close proximity to the mine workings <br />show a decrease in piezometric levels. One well, 29-4U, was subsided in 2013 <br />and the well became blocked. Well 30-8M is dry, the well is in a pillar located <br />next to the start line for LWB-8. Six wells showed an increase in piezometric <br />level and three wells showed a decrease in piezometric level. Three wells have <br />been plugged to eliminate connection with the surface; 29-4M, 32-7M and 32-7L. <br />Well Qal-5 is the only remaining alluvial well. The data from the full suite <br />analysis are all within the historical ranges. <br />- The point of compliance well, 22-3M, was sampled for the correct parameters and <br />frequency in the 2017 water year. Field measurements for pH, conductivity, <br />temperature and water level were completed in September. Samples were <br />collected and analyzed in a lab for total dissolved solids, dissolved iron and <br />dissolved manganese. <br />The effects of subsidence on Red Wash were predicted to be short-term. Ponding <br />in the stream bed and surface cracks in the alluvium were created by subsidence <br />of the drainage. Red Wash contains a high content of clay and silt sediments that <br />have filled in the cracks and depressions, maintaining the original stream channel. <br />Scullion Gulch has no observed surface hydrologic consequences due to the <br />effects of subsidence. <br />Discharge monitoring reports indicate that the DP -1 Pond, B Seam Dewatering <br />System and the Sewage Treatment PIant discharged during the 2017 water year. <br />The Facilities Area pond PP -2 did not discharge to Scullion Gulch during the <br />2017 water year. There was no discharge to Red Wash from any of the ponds <br />treating water from the refuse disposal area. Ponds RP -1, RP -213!4 and RP -5 are <br />designed to treat all the run-off from the waste piles. There are no springs or <br />seeps located in the refuse disposal area. The ponds associated with the Slot <br />Storage and Rail Loadout did not record any discharge. The SDH -3 D Seam <br />oF' C°lo <br />yam, r <br />555 Street Address, Roam 555, Denver, Co 55555-5555 P 555.555.5555 <br />s � <br />f 1876 �` <br />