Laserfiche WebLink
Comment: <br />3. Section III.A.2, oaee 2, list of metals standazds <br />The standards listed for azsenic, mercury, and selenium in the CDPI-IE Regulation <br />36 for Rio Grande Stream Segment 28 aze for the total recoverable form of the <br />metals, not total. <br />Elevated concentrations of aluminum have been reported in some backfill wells <br />(i.e., the BF-series wells) and seeps. Aluminum should be included in the list of <br />parameters. <br />Response: <br />No comment necessary. <br />The basic standazd for aluminum is dissolved. If a total concentration were used <br />to screen for the reasonable potential for aluminum, aluminum would likely be <br />assigned effluent limitations in every CDPS permit. Aluminum was considered <br />during the development of the permit. Appendix A to the Rationale presents data <br />for aluminum from the pit backfill, alluvial pumping wells, and seeps. As stated <br />in the draft permit, the initial detemunation was made that a permit limit for <br />aluminum would not be applicable. BMRI and its technical experts believe that <br />there is no reasonable potential for aluminum to be dischazged from the water <br />treatment facility, and therefore, contend that the original determination regazding <br />the exclusion of aluminum as an effluent limitation was correct. <br />Comment: <br />4. Section III.A.2, paee 3. last oazaeraoh <br />Station RS-2, specifically the period of record 1-11-90 through 7-20-1999, is not <br />representative of background hardness conditions in the Rito Seco. Station RS-2 <br />is located about 3,000 feet downstream of the West Pit and, as such, has been <br />influenced by BMRI mining actions for the entire period of record used. In <br />addition, review of the hardness data for Sta[ion RS-2 indicates a definite impact <br />due to leakage from the West Pit during the period 1998 and 1999. The six <br />hazdness values reported between December 21, 1998 and April 14, 1999 range <br />from 141.4 to 176.3 mg/L, CaCO~. Inclusion of these obviously impacted data in <br />the hazdness calculation is inappropriate. <br />Bartle Mountain Resources, /nc. HSl GeoTrans <br />15 July 21, 2000 <br />