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compared to effluent limitations in the Colorado Discharge Permit System requirements for Edna Mine <br />(CDPS permit number CO- 0032638). Values for Manganese were above the effluent limits (30 -day <br />average) in January 2010. The Water Quality Control Division (WQCD) at the Colorado Department of <br />Public Health and Environment is responsible for enforcing CDPS permit conditions including effluent <br />limitations, and Division records indicate that WQCD was notified of the exceedance in January. <br />Because the monitoring requirements no longer include water quality data from Trout Creek, it is not <br />possible to assess if surface runoff or sub - surface flow from the Edna Mine site is causing pollutant <br />concentrations in Trout Creek that are greater than standards. <br />Rule 4.05.12 Protection of Ground Water Recharge Capacity <br />Previous analysis by the Division has found that recharge to groundwater has been enhanced to a small <br />degree due to site stratigraphy, and permanent impoundments detain runoff, but overall disturbance to the <br />hydrologic balance in the permit area and in adjacent areas has been minimized. <br />Post - mining land use is supported by these impacts: ponds provide a water source for livestock and <br />wildlife, and spoil springs provide an extended recharge to Trout Creek. <br />The data in the 2010 AHR do not conflict with the previous analysis. <br />Rule 4.05.13(4) Surface and Ground Water Monitoring Report Requirements <br />Several springs and seeps were monitored for flow and water quality. Of the 15 springs, 12 were damp or <br />flowing and hydrologic data was collected. Of the 20 seeps, five were damp or flowing and hydrologic <br />data was collected. The analytical results for this data are tabulated in the 2010 AHR, and this report was <br />submitted by the date specified in the Permit Application Package (PAP), which is February 20. <br />In addition to the spring and seep data, flow and water quality are monitored at two discharge points, <br />Outfall 004A and Outfall 007A, as required by the Edna Mine CDPS permit. As noted above, this data <br />has been reported by Chevron in Discharge Monitoring Reports for 2010. <br />In previous years, data was presented in AHRs for several surface water and ground water monitoring <br />points (in addition to the two outfalls for CDPS compliance). Based on TR -47 and TR-48, monitoring at <br />these sites is no longer required, and no data is presented for these sites in the 2010 AHR. <br />For the Edna Mine, the Division does not require Chevron to provide a written interpretation of the data <br />or a discussion of mining related impacts to the hydrologic balance. <br />