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Dan Hernandez Page 11 <br />June 3, 2013 <br />through relatively porous streambed materials, with remaining flow progressing northeastward to <br />the Arkansas River, the major perennial drainage in this area. <br />Both Magpie and Second Alkali Creeks are unaffected by the Southfield mining activity. <br />Magpie Creek is a small ephemeral drainage with a drainage area of only 2.4 square miles. <br />Within the mine area Magpie Creek has been diverted to the southeast and flows through a <br />diversion channel. Second Alkali Creek drains the northwest corner of the Southfield Mine site <br />in an area which will not be disturbed by mining and related activities. <br />Newlin Creek is a major area drainage with a total drainage area of approximately 12.2 square <br />miles. The headwaters of Newlin Creek are in the Wet Mountains at an elevation of <br />approximately 11,000 feet and the stream flows approximately 14 miles from its headwaters to <br />its junction with Hardscrabble Creek approximately five (5) miles below the mine area. The City <br />of Florence constructed a drainage diversion on Newlin Creek located entirely within <br />mountainous terrain upstream of the Southfield Mine. The Newlin Creek diversion was <br />constructed in approximately 1880 as a municipal water source for the City of Florence. <br />Through condemnation and purchase, the City of Florence obtained rights to the entire flow of <br />Newlin Creek by an administrative water rights decision on November 24, 1915. The Newlin <br />Creek diversion consists of two 2 separate intakes with the upper intake collecting surface flows <br />and the lower intake capturing groundwater sub -flows. The dual diversion system is effective in <br />capturing essentially all surface and base flow in Newlin Creek as evidenced by the absence of <br />any base or sub -flow below the diversion. As a result of the diversion the Newlin Creek stream <br />channel is dry over the majority of the year from the point of diversion to the junction of <br />Newlin Creek with Hardscrabble Creek. Although Newlin Creek is mapped as a perennial <br />stream the City of Florence diversion results in ephemeral stream flow conditions below the <br />diversion as described above. In this stretch of stream, surface flows from Newlin Creek are <br />transferred to the groundwater system through the relative permeable Newlin Creek streambed. <br />These flows serve as recharge to the lower portions of the Vermejo Formation and the Trinidad <br />Sandstone. Each of these formations outcrops or subcrops to the east of the Southfield mine area <br />and are crossed by the Newlin Creek drainage as it flows northward to the junction with <br />Hardscrabble Creek. The City of Florence has historically diverted most of the available <br />streamflow of Newlin Creek upstream of the mine site, resulting in a dry stream channel for a <br />distance of about nine miles to Newlin Creek's confluence with Hardscrabble Creek. From a <br />short distance above the mine site to the confluence with Hardscrabble Creek below the mine <br />site, Newlin Creek is a losing stream. <br />Based on our analysis, groundwater in the Red Arrow and Dirty Jack O'Lantern coals does not <br />discharge to Newlin Creek as base flow as originally presumed. As previously described, <br />groundwater flow within the coal seams and Southfield underground workings within the permit <br />area is to the northwest in the down dip direction and flows beneath Newlin Creek. In the <br />immediate vicinity of Newlin Creek the coal seams mined are isolated from the creek by nearly <br />150 feet of overlying low permeability units. Water does not discharge to Newlin as previously <br />described in the 1987 report. In fact the opposite is occurring, Newlin Creek discharges to the <br />shallow alluvium and deep colluvial outwash deposits along the creek bed and possibly to the <br />underlying Vermejo Formation. The 1987 report also confirms that Newlin Creek is a losing <br />