2016-12-09_HYDROLOGY - M1977493 - Laserfiche WebLink

Home Browse Search

Demonstration of Compliance Climax Molybdenum Company With Regulation 41 Permit M-1977-493 Site Number Sample Date Manganese,Dissolved (mg/L) EVMW-3S 01/26/2016 0.064 EVM W-3S 06/08/2016 0.06 EVM W-3S O8/31/2016 0.047 Baseline Average 0.039 Baseline Std.Dev.(o) 0.036 Mean+20 0.111 Monitoring data in Appendix B were compared against this value in accordance with Section 5.2.1 of the WQMP; maintaining manganese at this level would be in compliance with Regulation 41. 4.2.3 Ambient-Based Manganese Value for EVMW-3D EVMW-3D is a deeper bedrock POC well, constructed in September 2011 near the Climax property boundary above the East Fork of the Eagle River and downgradient of Eagle Park Reservoir. Sampling at this location was conducted on a quarterly basis beginning in November 2011, with additional monitoring for manganese on a more frequent basis in 2014. As described previously, there have been no new or increased sources of groundwater contamination initiated in the area subsequent to January 31, 1994, and the variable manganese concentrations observed in groundwater at this well are believed to be influenced by naturally occurring sources or conditions. These data are deemed suitable to determine existing ambient quality representative of groundwater quality as of January 31, 1994. Table 4-2 lists all results for manganese at this well through the third quarter of 2016 and the calculation of the ambient value. Table 4-2: Ambient-Based Manganese Calculation for EVMW-3D Manganese,Dissolved Site Number Sample Date (mg/L) EVMW-3D 11/15/2011 0.01 EVMW-3 D 01/31/2012 0.005 EVMW-3D 06/19/2012 0.011 EVMW-3D 09/25/2012 0.057 EVMW-3D 12/27/2012 0.012 EVMW-31) 03/11/2013 0.066 EVM W-3 D 06/27/2013 0.078 EVMW-3D 08/14/2013 0.019 EVMW-3D 11/06/2013 0.017 EVMW-3 D 01/29/2014 0.0187 EVMW-31) 02/27/2014 Inaccessible EVMW-3 D 03/25/2014 0.006 EVMW-3D 04/25/2014 0.0091 December 2016 17