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Project Descri bons AddanBrown <br /> monew <br /> SEEP AND SPRING EVALUATION, NEVADA <br /> AdrianBrown was retained to perform an annual seep and spring inventory for a large mining operation <br /> in Nevada. The objective of the study was to determine potential impacts to the local seep and spring <br /> hydrology as a result of mine dewatering activities. Specific project tasks conducted by AdrianBrown <br /> include development of the sampling and analysis plan,seep sampling,flow measurements,vegetation <br /> monitoring, and reporting. <br /> AdrianBrown collected water samples from more than thirty seep and spring locations. Samples were <br /> analyzed for the major ions, trace metals, tritium, and stable isotopes. Tritium and stable isotopes were <br /> collected from each location to evaluate the genesis of the seep and spring waters, Seep and Spring <br /> flowrates were gauged at all sampling locations with measurable amounts of flow. AdrianBrown <br /> employed a number of different methods tailored toward site-specific flow conditions. This provided a <br /> higher degree of accuracy for each flow measurement as dictated by the flow conditions present at the <br /> site, specifically the amount and depth of flow. Seep or spring sites with moderate amounts of flow <br /> were measured using a 1-inch or 4-inch cutthroat flume for flowrates of less than 115 gpm. A Marsh <br /> McBimey flowmeter was used for flowrates exceeding 115 gpm. Seeps and springs exhibiting a low <br /> volume of flow(less than 1 gpm)were estimated using a volumetric excavationlfill technique. <br /> AdrianBrown utilized the services of Dr. Warren R. Keammerer, Plant Ecologist, under subcontract <br /> for the vegetation portion of the study. The annual vegetation study was crucial for identifying the <br /> effects of severe or even subtle changes in the site hydrology on vegetation. The point transect method <br /> was employed as opposed to the Daubenmire approach, since it is more accurate in defining changes in <br /> vegetation type. The point transect method provided for a higher degree of repeatability while <br /> maintaining a consistent plant species inventory. <br /> The seep and spring study included a compilation of the acquired data including a comprehensive <br /> database that contained previously collected data from all the annual studies. These historical data were <br /> updated with the newly acquired data and evaluated annually. The emphasis of the study was to <br /> determine the genesis and chemical signatures of the seeps and springs. These components were <br /> carefully compared to annual variations in flow,climate,and vegetation. <br /> The final report included site descriptions, a summary of the data acquisition activities, analytical results, <br /> interpretations of the seep hydrology and water chemistry, results and interpretations relevant to the <br /> vegetation sampling, and conclusions regarding the impacts from the Betze Pit mine dewatering <br /> activities to the surrounding hydrology. Overall, the annual seep and spring study has been a success in <br /> terms of cooperative efforts between the mining facility and regulatory authority to ensure of minimal <br /> impacts to the surrounding environment. <br />