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Scott Wanstedt <br />Page 2 <br />Feb. 17, 2016 <br />Predicted by the PHC, Monitoring wells in close proximity to the mine workings show a decrease <br />in piezometric levels. One well, 29-41J, was subsided in 2013 and the well became blocked. <br />Well 30-8M is dry, the well is in a pillar located next to the start line for LWB-8. Four wells <br />showed an increase in piezometric level, four wells showed a decrease in piezometric level and <br />one well (22-3U) remained unchanged. Three wells have been plugged to eliminate connection <br />with the surface; 29-4M, 32-7M and 32-7L. Well 33-8U was cleared of the dead rodent and the <br />water level was obtained. The water level was measured to be at 276.6 feet. Well Qat-5 is the <br />only remaining alluvial well. The data from the full suite analysis are all within the historical <br />ranges. <br />The point of compliance well, 22-3M, was sampled for the correct parameters and frequency in <br />the 2015 water year. Field measurements for pH, conductivity, temperature and water level <br />were completed in September. Samples were collected and analyzed in a lab for total dissolved <br />solids, dissolved iron and dissolved manganese. <br />- The effects of subsidence on Red Wash were predicted to be short-term. Ponding in the stream <br />bed and surface cracks in the alluvium were created by subsidence of the drainage. Red Wash <br />contains a high content of clay and silt sediments that have filled in the cracks and depressions, <br />maintaining the original stream channel. Scullion Gulch has no observed surface hydrologic <br />consequences due to the effects of subsidence. <br />- Discharge monitoring reports indicate that SDH -3/5 and the Sewage Treatment Plant discharged <br />during the 2015 water year. The SDH -3/5 Dewatering System had exceeded the parameters <br />for Iron and failed the WET tests in the third quarter. MR -166 was submitted to expand the <br />dewatering system and to increase the retention time. The Minor Revision was not approved <br />until after Water Year 2015 had ended. BME is following the correct procedures outlined in <br />the NPDES Permit, CO -0038024, to address the WET testing failures. The Division has <br />received updates from BME as testing progressed. BME will continue to provide information <br />to the Division along with any new decisions made by or between the Water Quality Control <br />Division and BME. The Facilities Area ponds DP -1 and PP -2 did not discharge to Scullion Gulch <br />during the 2015 water year. There was no discharge to Red Wash from any of the ponds treating <br />water from the refuse disposal area. Ponds RP -1, RP -2/3/4 and RP -5 are designed to treat all <br />the run-off from the waste piles. There are no springs or seeps located in the refuse disposal <br />area. The ponds associated with the Slot Storage and Rail Loadout did not record any discharge. <br />The mine site also receives a low amount of annual precipitation. <br />This concludes the Division's review of the 2015 Annual Hydrology Report for the Deserado Mine. The <br />Division has no further comments or questions. If you have any questions, please contact me at (303) <br />866-3567 x8144. <br />