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EPP Adequacy Review No. 2 5 19 March 2010 <br />Schwartzwalder Mine File No. M-1977-300 <br />all surface and ground water samples. The extended analyte suite for surface water shown on <br />page 5 of 7 should be expanded to include Phosphorus and Nitrate + Nitrite. As recommended <br />by CDPHE, the surface water sampling suite must also include Gross Alpha and Gross Beta. <br />The extended analyte suite for monitoring wells, domestic wells and sumps shown on page 6 of 7 <br />must be expanded to include Phosphorus and Nitrate + Nitrite. As recommended by CDPHE, <br />the sampling suite for monitoring wells, domestic wells and sumps must also include Gross <br />Alpha and Gross Beta. Concurrently with the plan as proposed, all surface water, ground water, <br />and sump monitoring locations must be analyzed for the extended suite on a quarterly basis. <br />SECTION 15. MITIGATION OPTIONS AND CONSTRUCTION SCHEDULE <br />16) On page 15-1 and in other sections of the EPP, the Operator states that limited source removal of <br />contaminated material will be performed in the alluvium as part of RML termination. In light of <br />the elevated uranium concentrations that have been reported over the last year in alluvial <br />monitoring wells (MW3A, MW6, MW9, and MW 12) and in Ralston Creek (SW-BPL, SW- <br />FBRG, SW-ARH, and SW-LLHG), DRMS strongly recommends that the Operator scrutinize <br />this plan to ensure that source material removal is as thorough as possible to minimize potential <br />future loadings from the alluvium to ground water and surface water. Detailed plans and <br />schedules must be provided to implement complete source removal and impact mitigation. <br />17) On page 15-3, Operator states that they may "seek higher alternate concentration limits (ACLs) <br />based on human health risk." Operator is reminded that, under §34-32-116(7) (g) C.R.S., DRMS <br />is required to protect the `prevailing hydrologic balance.' In this context, DRMS will evaluate <br />environmental impacts relative to baseline conditions rather than impacts or perceived risk to <br />human health or aquatic life. <br />18) On page 15-3 Operator proposes a constructed wetland. Constructed wetlands do not always <br />ensure effective treatment, and long term maintenance is required. Please describe in detail, the <br />composition and construction of the wetland, the proposed loading rates, the expected <br />geochemical attenuation processes, and the expected water quality that will ultimately be <br />discharged from the wetland at the down gradient terminus. Please also provide maintenance and <br />bonding details. <br />19) Regarding the proposed wetland, the process flow scheme is not clear. Is the wetland designed <br />to capture only alluvial ground water, and thus mine pool water would not be routed to the <br />facility? <br />20) The literature suggests that proper design of a wetland is best preceded by laboratory, bench <br />scale, and pilot testing. Please provide a description of an appropriate testing program that will <br />evaluate the capability of the proposed substrate to remove the contaminants of concern at the <br />site. <br />21) On page 15-4 Operator states that "monitoring would be performed for up to 10 years to <br />demonstrate that the wetlands are functioning as designed ....." DRMS does not accept the