2015-01-14_REPORT - C1981035 (4)

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The current weather cycle is in a warming phase. With this trend increased evaporation rates coupled with reduced precipitation can produce upward trends in the concentration of selected analytes due to a simple reduction in supplies of water. CDS subjected the analytical data to trend analysis using formulas within Excel ®. Each data set was analyzed for best fit using linear, polynomial and exponential methods. In all but three cases the linear trend analysis provided the best fit. Because many of the reported parameters vary considerably from quarter to quarter, trend analysis will provide a mathematical trend which may or may not be statically significant. For example, in the King II Up- gradient monitoring well, the sampled Manganese levels exhibit a high degree of variability. Even with this variability there is a significant ten year upward trend in Manganese concentration from about 0.005 mg /L to about 0.035 mg /L. However, other parameters also demonstrate linear trends, but because of high variability the trend may not be statically significant. That being said, in some cases it is our professional opinion that a particular trend may be real over longer periods of time, such as 10+ years. Precipitation history and tree ring analysis indicates the area around both King I and King II mines is plagued by cycles of wet and dry that run for a few years up to decades. Even with the cycles much of the precipitation comes in the form of short lived downpours which can deposit Y4 or more of the annual average rainfall in a single event. This makes the interpretation of quarterly water analysis difficult at best. Since all sampling wells derive their water from the Hay Gulch alluvial floor they may share a similar wet -dry cycle. In addition, the Hay Gulch Ditch, which derives its water from the La Plata River, will reflect its flow and chemistry variations. The Hay Gulch valley floor receives water from all slopes draining into its alluvium. Its chemistry will reflect the surface leaching of the exposed shale, mudstone, and sandstone outcroppings along the valley walls. Each of these two sources of water are different. The La Plata River drainage comes from alpine zones where minerals are slowly derived from hard rock formations, while the runoff into the valley floor comes from contained shale, mudstone and sandstone formations which tend to leach minerals quickly. So it is safe to assume the King I & II monitoring sites derives there water from more than a single source. This "mixing" of water sources can and does produce a complex family of water types, which are seen in these monitoring sites. Section Summary: Conditions supporting the sampling sites for both King I and King II Mines are such that great variations in water chemistry can be expected. Trend analysis of reported quarterly sampling yields linear or polynomial plots which in some cases are significant. Summary of analytical data: CDS will summarize below the analytical data from each sampling site and provide limited interpretation of the data provided by GCC monitoring. A summary and conclusions are seen at the end of this section. • King I Mine — Haugen Well — Only sampled between 8/1/2000 and 12/1/2006. There is significant trend upward in water temperature. Data on water depth is not available to correlate with ground temperature. A downward trend in TDS and field EC suggests an influx of low TDS warmer water into this well.