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PR-12 Exhibit 71 <br />0. <br />4.0 COMPREHENSIVE HYDROLOGIC MONITORING PLAN <br />4.1 Summary <br />14 <br />MCC has implemented an extensive water quantity and water quality monitoring plan for streams, springs, and <br />ground water resources in the Minnesota Creek and the North Fork of the Gunnison drainage areas that could be <br />potentially affected by WEM mining operations. Strategically selected surface and ground water monitoring sites <br />provide pertinent data and trends with regard to changes in water quantity and quality. This information allows <br />MCC to determine what, if any, impacts are occurring to the mine area water resources as a result of mining <br />activity. The data collected during the hydrologic monitoring process are analyzed on an annual basis and MCC <br />reports the results of these analyses to the CDMG in the Annual Hydrology Report. If significant water quality or <br />quantity changes are noted during the monitoring, MCC is obligated to report the changes immediately to the <br />CDMG. MCC plans to expand into new mine areas and consequently needs to periodically revise the existing <br />hydrologic monitoring plan to continue to provide adequate baseline and on-going monitoring data and to comply <br />with permitting requirements. The locations of the current and future hydrologic monitoring sites are discussed <br />below and shown on Map 1. Monitoring of USFS surface water resources and the subsidence monitoring plan for <br />the SOD is presented in Sections 2.04.7 (2) and 2.05.6 (6) on the PR-10 permit document, respectively. <br />4.2 Hydrologic Monitoring Plan <br />The hydrologic monitoring plan for the WEM includes monitoring surface water resources, springs and seeps, <br />ground water resources, the underdrain, and pertinent mine water sites. Routine monitoring includes collecting <br />field water quality data (pH, electrical conductivity (EC), and temperature) and collecting a sample for <br />independent laboratory analysis annually. Flow or water level measurements are collected three times per year. <br />The three monitoring periods correspond with the rising limb period between April 3`a and May 13th, the peak <br />flow period between April 21St and June 26th, and the low flow period between July 10th and October 8th as shown <br />on Table 5. The chemical analysis suite for the first five years of sampling, including baseline sampling, is <br />presented in Table 6 as well as field parameters (pH, conductivity, temperature, and flow or water level). After <br />sites have been monitored more that 5 years, the analytical suite parameter list will be reduced to field parameters <br />(pH, conductivity, temperature, and flow or water level) and laboratory analysis for total suspended solids (TSS), <br />total dissolved solids (TDS), conductivity, pH, and iron (Fe [dissolved & total]). The North Fork monitoring sites <br />have an expanded analytical suite, because of on-going characterization of this river. The North Fork lab <br />parameters include those listed in Table 6 plus alkalinity, carbonate, hydroxide, and ortho-phosphate. <br />The hydrologic monitoring plan incorporates a separate baseline monitoring schedule for approximately one year <br />prior to expanding mine development in new areas for newly added monitoring sites (CDMG, 2005b). The <br />baseline schedule includes collecting monthly field water quality data, flow or water level measurements, and <br />September 2007 ffrdroGeo, Inc. <br />11