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channel emergency spillway designed for the 25-year, 24-hour precipitation event. <br />The sedimentation pond is discussed in Section 2.4.4 of the text, and designs are <br />depicted on Figure 2.2-3. <br />The sediment pond was filled in with sediment by a 100 year magnitude storm event <br />in August 2001 that had buried and overwhelmed one of the primary upland <br />diversion culverts. In association with excavation of sediment, the inside slopes of <br />the sediment pond were reduced to approximately 2H:1 V. The re-constructed pond <br />was properly certified by a professional engineer (see "Impoundment Yearly <br />Inspection" of March 29, 2002). The pond embankment failed in 2004, apparently <br />as result of leakage from the buried primary discharge pipe. The embankment was <br />reconstructed and the primary discharge pipe was replaced. Embankment <br />reconstruction was properly certified (see "Sediment Pond Certification" of <br />December 14, 2004). <br />D. Surface and Ground Water Monitoring <br />GROUND WATER <br />Information provided by the applicant with respect to ground water in the permit area <br />can be found in 4.2.2 through 4.2.4 of Volume I of the permit application. The <br />monitoring plan is described in Section 4.2.4, and monitoring parameters are <br />specified in Table 4.2-15. <br />As discussed in the Probable Hydrologic Consequences (PHC) section of this <br />document, no significant effects to bedrock or alluvial ground water systems are <br />anticipated for this operation. The applicant will conduct monitoring of ground <br />water in a manner approved by the Division to verify the projections of the PHC. <br />The ground water monitoring plan is as follows (4.05.13(1)): <br />1. Quarterly monitoring of alluvial wells GW-1 and GW-9 for static <br />water level, pH, temperature, and specific conductance. <br />2. Water quality sampling of mine water discharges as required by <br />CDPS permit. <br />3. Monitoring of all non-seep inflows into the mine to include <br />source, quantity, duration and quality (pH, electrical conductance, <br />and temperature). <br />4. Monitoring of quantities of water discharged from the mine, <br />consumed in the mine, and imported for use in the mine. <br />Results of the quarterly ground water monitoring are submitted to the Division <br />during the month following the end of that quarter. Monitoring results and <br />evaluation for ground water and surface water are submitted in an annual hydrologic <br />report (AHR). The AHR will detail inflows, discharges and consumption of water <br />within the mine and shall be structured around the normal "water year" (October 1 <br />17