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on historic site -wide data. As described in the WQMP, the indicator parameter lists will be reviewed <br />following the collection of baseline data and revised as necessary. <br />- DRMS views NPLs as trigger levels — statistical analysis is not required. If an established NPL is exceeded, <br />it will trigger the steps listed in section 5.1.2. DRMS will need to be notified to collect split samples of any <br />required confirmation sampling for NPL exceedance. <br />Climax believes that the statistical evaluation of data collected for compliance monitoring is important and <br />necessary to differentiate outliers and potential false positives. However, based on discussion with <br />DRMS, the WQMP has been revised to simplify the evaluation of data against the NPL. As described in <br />the WQMP, NPLs for the POC wells will be established in accordance with DRMS Rules and the Interim <br />Narrative Standard, for unclassified groundwater, in the Colorado Basic Standards for Groundwater <br />(CBSG) (WQCC Regulation 41). In accordance with these rules, NPLs for each parameter will be <br />established at the least restrictive of existing ambient quality or the most stringent numeric criteria set <br />forth in Tables 1 through 4 of the CBSG. In the situation where an NPL is selected based on <br />ambient/baseline data, the NPL will be established as the mean concentration plus two standard <br />deviations for the ambient data set, per our previous discussions. Notification of exceedance of an NPL <br />is described further in the WQMP. <br />Interceptor Ditch System <br />Section 6.4.21 (10) of the Hard Rock Rule states that EPFs intended to "convey, transport, or divert surface <br />water around or away from acid mine drainage or toxic or acid - forming material; or capture and /or retain <br />surface water run -off from areas protected by the Designated Mining Operation prior to its release from the <br />mine site into the natural drainage system" need to be designed and certified by a licensed professional <br />engineer. In previous discussions with Climax, due to the pre -law construction and extent of this interceptor <br />system, DRMS had agreed that only new or modified sections of the interceptor system would be required to <br />be designed and certified by an engineer. Upon further review, DRMS has determined that the rule does not <br />allow this distinction. However, DRMS does acknowledge the magnitude of this requirement for the facility, <br />and that the existing system is functioning as intended at this time; therefore, DRMS will not make certification <br />of the existing interceptor system a pre- requisite for the restart of operations. Please provide a plan and <br />proposed schedule for the certification of the design and construction of the interceptor system to pass the <br />10yr/24hr precipitation event for the site. <br />Climax does not agree with the Division's interpretation, and believes there is justification that the <br />interceptor systems are not EPFs by definition and therefore not subject to the "design specification" <br />requirements cited above from Section 6.4.21(10). However, Climax will agree to perform an evaluation <br />of the interceptor systems. <br />Canal or ditch inspections are most effective if performed during an operating condition, preferably during <br />a relatively high flow scenario. Actively conveying water through the canal during the inspection helps to <br />more readily observe and identify areas with limited capacity. Therefore, Climax proposes to conduct a <br />comprehensive inspection of the interceptor systems during the upcoming snowmelt runoff period in the <br />spring of 2012. The data collected from the initial inspection, subsequent field surveys, if warranted, and <br />hydrologic analyses will then be used to determine that the systems can safely pass a 10 -yr / 24 -hr <br />rainfall event. <br />12 <br />