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Groundwater Monitoring & Response Plan <br />Elam requested modification of the mine permit to allow dewatering of the deposit to facilitate <br />extraction of sand and gravel to the permitted mine depth of 35 feet bgs. Because groundwater <br />has been documented to occur between depths of 8 to 14 feet bgs at the site, the Pit would need to <br />be dewatered to a depth of about 25 feet below the existing water table. To support Elam's <br />request for a permit modification, WWL conducted a hydrologic evaluation designed to assess the <br />potential impacts to groundwater levels in response to dewatering operations at the Pit. The <br />evaluation included construction and execution of a site - specific numerical groundwater model to <br />predict groundwater level responses in the vicinity of the Pit to dewatering operations. Evaluation <br />findings and model results are described in Groundwater Hydrology Report; Dillon Ranch Pit <br />(WWL, 2013). <br />Elam will dewater the Pit two months per year during the permitted mine period of November <br />through March and will implement the Plan as described herein. The Plan will provide the data to <br />actively monitor water levels within the defined monitoring network prior, during, and after <br />active dewatering at the Pit each year. Monitoring results will also be used to update and refine <br />the predictions forecast by the site - specific numerical groundwater model. <br />7.2 Site Description <br />The Pit is located in La Plata County in the Animas River Valley approximately 7 miles north of <br />Durango, Colorado (Figure 1). The Pit is in the NW 1/4 of the NW 1/4 of Section 14, Township 36 <br />North, Range 9 West of the New Mexico Principal Meridian. The Pit is situated on a flood plain <br />adjacent to the Animas River, at an elevation of about 6,576 feet (NAVD 88). The Pit is located <br />on land owned by Dillon Ranches LLLP. <br />Geologic deposits at the Pit consist of alluvial sand and gravels characterized as stream - channel, <br />floodplain, and low terrace deposits. These deposits overlie bedrock formations that include the <br />Hermosa Group, Leadville Limestone, Ouray Limestone, and the Elbert Formation. The sand and <br />gravel deposits serve as an unconfined aquifer. According to a 2004 hydrology study report <br />prepared by Southwest Hydro- Logic, the depth to water in the unconfined aquifer at the Pit varies <br />between 8 to 12 feet bgs. Information included in the well permit file for the Pit (Well Permit No. <br />64853 -F) indicates the exposed water table surface at the Pit was surveyed at 14 feet bgs on <br />March 4, 2005. <br />Western Water & Land, Inc. 2 <br />