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PR-12 Exhibit 71 . 5 <br />date do not indicate any mining related impacts. The water quality data do, however, reflect natural seasonal <br />variations with respect to levels of manganese, pH, and TDS being elevated during spring runoff. <br />2.1.4 South Prong Creek <br />South Prong Creek is an ephemeral stream tributary to Minnesota Creek and is located upstream of Lick <br />Creek (Map 1). The north fork of South Prong Creek drainage drains the extreme southeast corner of the <br />SOD area and is well outside the mine panel area (-0.5 miles). As a result, mining related hydrologic <br />impacts from the PR-10 activities are not anticipated in the South Prong Creek drainage area. <br />The north fork of the South Prong Creek watershed encompasses an area of about 0.5 square miles. The <br />drainage is about 0.1 miles long, extends from an elevation of approximately 8,400 feet to 7,800 feet, and <br />has an average gradient of about 10 percent. The north fork of South Prong Creek is a steep narrow <br />drainage with a limited alluvial valley floor. The incised channel restricts the width of alluvium. The <br />relatively steep stream gradient and the presence of sandstone outcrops limit the thickness and presence of <br />alluvium. The baseflow in this drainage originates from several springs. MCC preliminarily monitored <br />flows and collected water quality data in South Prong Creek in the spring of 2005 and will begin actual <br />monitoring in 2017. There are not sufficient water quality data to determine if there are any mining <br />related impacts or natural seasonal water quality variations at this site. <br />2.2 Stock Ponds, Springs, and Seeps <br />In July 2004 WWE completed a stock pond, spring and seep survey of the SOD area (WWE, 2005). The <br />boundaries of the WWE study area for this survey extended beyond the designated boundaries of the SOD <br />area and PR-12 application area. Stock ponds were included in the survey results if they held water at <br />least seasonally. Stock ponds were not included if they were in disrepair and/or could no longer hold <br />water. For survey purposes, springs were defined as "areas where ground water issues for at least part of <br />the year, and there is observable flow". Seeps were defined as "areas where ground water saturates soils <br />but do not have flowing water'. A total of 25 stock ponds, 16 springs, and 82 seeps were inventoried in <br />the WWE SOD study area during the NVWE survey (WWE, 2005). <br />Stock ponds in the SOD and PR-12 areas are filled by natural surface water runoff or are fed by springs or <br />seeps. There are three different types of springs and seeps in the SOD and PR-12 areas, including those <br />which issue from alluvium, colluvium, and bedrock. Recent data indicate that about 65 percent of the <br />springs and seeps issue from alluvium or colluvium; 35 percent issue from bedrock, and only about 5 <br />percent issue from the Upper or Lower Coal Series strata (CDMG, 2005a). The flow activity of the <br />springs and seeps is seasonal and also varies with long term climatic conditions such as droughts. <br />Typically, flows are greatest in the sprir: months and/or during wet climatic periods. Flows generally <br />decrease in late summer and fail and-or during dry climatic periods. Some springs are ephemeral, <br />September 2007 1`i-droGeo, lnc. <br />•