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Kurt Blunt <br /> Page 2 of 3 <br /> 2/5/2020 <br /> inflow of water into the mine was approximately 8.21 gpm in the 2019 water year. <br /> The value is in the predicted range of 5 to 10 gpm. In May of 2012 a dewatering <br /> pump system was installed to pump excess water captured in the underground <br /> mine to the surface. Water pumped to the surface from the B Seam in the 2019 <br /> water year was 26,599,615 gallons or 50.61 gpm. Water pumped from the SDH- <br /> 3/5 D-Seam Dewatering System during the 2019 water year was 151,904,274 <br /> gallons or 289.01 gpm. <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. Wells 30-8M and 32-7U remained dry. Five wells <br /> showed an increase in piezometric level and four wells showed a decrease in <br /> piezometric level. One well, 33-8M, remained at the same level as the previous <br /> year. Three wells have been plugged to eliminate connection with the surface; <br /> 294M, 32-7M and 32-7L. Well Qal-5 is the only remaining alluvial well. The <br /> data from the full suite 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 2019 water year. Field measurements for pH, conductivity, <br /> temperature and water level were completed in December 2018, March 2019, <br /> June 2019 and August 2019. Samples were collected and analyzed in a lab for <br /> total dissolved solids, dissolved iron and dissolved manganese in August 2019. <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 and the 2019 AHR indicate that outfalls 001 (DP-1), <br /> 026 (SDH-3) and 029 (B Seam Dewatering System No. 1) discharged during the <br /> 2019 water year. The Facilities Area pond PP-2 did not discharge to Scullion <br /> Gulch during the 2019 water year. There was no discharge to Red Wash from any <br /> of the ponds treating water from the refuse disposal area. Ponds RP-1, RP-2/3/4 <br /> and RP-5 are designed to treat all the run-off from the waste piles. There are no <br /> springs or seeps located in the refuse disposal area. The ponds associated with the <br /> Slot Storage and Rail Loadout did not record any discharge. The mine site also <br /> receives a low amount of annual precipitation. <br /> This concludes the Division's review of the 2019 Annual Hydrology Report for the <br /> Deserado Mine. The Division has no further comments or questions. If you have any <br /> questions,please contact me at(303) 866-3567 x8144. <br />