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ilk <br />Natural Soda LLC <br />2015 Project Status Report & Annual Plan of Development <br />5.1.3 Monitoring Wells <br />Per regulatory requirements, dedicated monitoring wells have been constructed to <br />monitor four water -bearing zones; Perched, A -Groove, B -Groove, and the Dissolution <br />Surface aquifers. The aquifers are monitored at several locations across the solution <br />mining area; down -gradient, up -gradient, remote down -gradient, and east near the <br />southeast portion of Section 26. Refer to Figure 3 and Figure 4 for well locations. <br />Baseline and current ground water monitoring data have been obtained from 1991 <br />through present. Within NS's lease boundaries, there are three aquifers defined by US <br />EPA as underground sources of drinking water (USDW): the Perched, A -Groove and B - <br />Groove Aquifers. The Dissolution Surface Aquifer is not designated as an underground <br />source of drinking water. <br />The Perched Aquifer is characteristically lower in total dissolved solids (TDS), <br />conductivity, fluoride, SAR (sodium absorption ratio) and moderate to higher in sulfate <br />and pH. The A -Groove and B -Groove aquifers are similar in water quality with <br />moderate TDS, conductivity, SAR, but higher fluoride. However, the B -Groove aquifer <br />generally has slightly higher levels of TDS, conductivity, SAR, and fluoride. The <br />Dissolution Surface Aquifer is characterized by very high TDS and conductivity (30,000 <br />to >100,000 ppm), higher SAR, magnesium, potassium, and a moderate pH. <br />In 2015 the results of groundwater monitoring were analyzed for potential anomalies in <br />order to prevent or mitigate potential negative impacts to the USDW's. <br />Appendix A contains detailed sampling results for all ground water monitoring wells. <br />5.1.4 Process Ponds <br />The process ponds at the NS site have a secondary liner, which collect and direct any <br />condensation or leakage to the leak detection tube for removal. Weekly collection and <br />removal of leachate continued in 2015. Process pond information is reported on a monthly <br />basis. <br />5.1.5 Potentiometric Surface Maps <br />Using groundwater level elevations from NS groundwater monitoring wells and other NS <br />wells, the potentiometric surface has been plotted for the A -Groove and B -Groove <br />Aquifers. A map representing the potentiometric surface for the A -groove and B -groove <br />has been included with this report in Appendix C. <br />DAUB & ASSOCIATES. INC. • <br />22 January 2016 <br />