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Accompanying this submittal are graphs incorporating all available data for the above parameters, plotted as parameters through time. For this purpose, data are available for Newlin Creek - upper and lower, Magpie Creek - upper and lower, and Second Alkali Creek. An analysis of the data shown on the graphs for the three creeks (five monitoring points) follows. All graphs include a trend line. Since there are considerable fluctuations in the data, a moving average trend line is shown on each graph to show a pattern or trend more clearly. TDS and TSS levels are important parameters to consider in terms of stream water quality. In particular, the PHC cites TDS as a quality indicator parameter. A review on the data provided for upper and lower Newlin Creek points shows TDS levels staying in a close range from about 2000 through the \ latest sampling, while values ranged more widely from 1997 to 2000, with higher levels shown for the lower monitoring point. For the same time period, TSS levels varied up and downward, and for both points there is a possible downward trend in levels beginning in about 2005. For Magpie Creek, TDS data shows a wide range of values at both monitoring points, with slightly higher values at the lower location. A possible upward trend of TDS levels is evident at the upper monitoring point. Levels of TSS similarly have a wide range at both monitoring points, and show significantly higher average values at the upper location. Only the upper point shows a possible trend of decreasing values over the latest four years of data Very few samples are available for TDS and TSS from Second Alkali Creek. The data provided shows a wide range of values for both parameters over time. A downward trend is indicated for both parameters, but is difficult to verify based on so little data. It is important to note that Second Alkali Creek was not undermined by Southfield and therefor probably not affected by mining. A review of data for the remaining parameters, from the aforementioned list, show variations in values over time with no significant trends in quality over the range of years. In addition, no discernible trends are apparent for these parameters comparing the applicable upper and downstream monitoring points. The data do show that water quality can vary through a given year Also, quality is likely affected by the intensity of a given storm event that produces flow, and also by the prevailing drought conditions. Based on the available data as provided, we conclude that water quality in Newlin Creek, Magpie Creek, and Second Alkali Creek were not adversely affected by the Southfield mining activity. r a Iii i • U ► • ► • ru • ;i ; • n !limit • iii Igo i.: ► • ) •1 i s0 • g• Probable • • •ea •�► -am ' Within the Adequacy Review, the Division agrees with the general assertion made by EFCI (in the TR-43 Application package dated October 24, 2014) that the groundwater quantity monitoring data that has been presented supports the PHC predictions. The referenced PHC predictions related to groundwater include the following: • Minor reductions in down - gradient groundwater flows • Possible dewatering of abandoned mines in the Vento seam • Localized reductions in the piezometric surface • Localized alteration of groundwater flow patterns • Possible increases in recharge as a result of mine dewatering