Laserfiche WebLink
Demonstration of Compliance Climax Molybdenum Company <br /> With Regulation 41 Permit M-1977-493 <br /> 3.2.3 Ambient-Based Manganese Value for ARK-MW-001D <br /> ARK-MW-001 D is a relatively new deep bedrock well, constructed adjacent to the shallow ARwell <br /> in September 2012. Sampling began with two samples collected in October 2012. This well is <br /> artesian (flowing at the land surface) and was inaccessible during the next two events due to <br /> freezing conditions, and was therefore not sampled in March or June 2013. Quarterly sampling <br /> resumed in August 2013 and continued through the end of 2014, with no further issues <br /> encountered after the well was retrofitted with a frost-free valve. From February to November <br /> 2015, monitoring was performed on a monthly basis to collect additional data for the purposes of <br /> establishing baseline conditions. As described for ARwell, there have been no new or increased <br /> sources of groundwater contamination initiated in the Arkansas River Watershed subsequent to <br /> January 31, 1994. Due to the location of this well, adjacent to ARwell, and the record of improving <br /> quality in the shallow aquifer at this location as demonstrated by the data collected since 1993, <br /> the use of more recent data is appropriate for representing ambient quality as of January 31, <br /> 1994. Furthermore, the use of the full period of record from October 2012 through August 2016, <br /> allows the consideration of the variability in observed concentrations over time in estimating the <br /> representative ambient quality. Table 3-2 lists all results for manganese at this well through the <br /> second quarter of 2016 and the calculations for the ambient value. <br /> Table 3.2: Ambient-Based Manganese Calculation for ARK-MW-001D <br /> Site Number Sample Date Manganese, <br /> Dissolved(mg/L) <br /> ARK-MW-001D 10/1/2012 0.012 <br /> ARK-MW-001D 10/18/2012 0.011 <br /> ARK-MW-001D 3/13/2013 Plugged <br /> ARK-MW-OO1D 6/27/2013 Plugged <br /> ARK-MW-001D 8/13/2013 0.056 <br /> ARK-MW-001D 11/19/2013 0.026 <br /> ARK-MW-001D 2/12/2014 0.303 <br /> ARK-MW-001D 6/18/2014 0.097 <br /> ARK-MW-001D 9/10/2014 0.014 <br /> ARK-MW-001D 12/4/2014 0.012 <br /> ARK-MW-001D 2/24/2015 0.015 <br /> ARK-MW-001D 3/10/2015 0.016 <br /> ARK-MW-OO1D 4/13/2015 0.182 <br /> ARK-MW-OO1D 5/26/2015 0.016 <br /> ARK-MW-001D 6/16/2015 0.022 <br /> ARK-MW-001D 7/28/2015 0.012 <br /> ARK-MW-001D 8/31/2015 0.192 <br /> ARK-MW-001D 9/22/2015 0.013 <br /> ARK-MW-001D 10/14/2015 0.009 <br /> ARK-MW-001D 11/12/2015 0.073 <br /> December2016 9 <br />