Laserfiche WebLink
cccf-- <br /> CIVIL RES'VURCES <br /> As noted above in the discussion of the Division's implementation of Rule 41, at the time of approval this plan <br /> exceeded the monitoring requirements for similar permits issued in the Platte River alluvial watershed prior to <br /> and during the time of this application. The plan was written to include the following: <br /> a. A site wide discussion of the hydrogeologic setting prior to disturbance. <br /> b. Allows for a determination of the effects of the permitted activity on the quantity and quality of <br /> groundwater and includes monitoring points upgradient and downgradient of the proposed activity. <br /> c. Specifies that the Division will be notified within seven (7) days if any of the standards had been <br /> exceeded at the wells sampled. The wells specified for sampling were included upgradient and <br /> downgradient at the permit boundary. <br /> Although a sampling protocol was not included in the plan to give operational leeway on sampling methods <br /> used, the sampling protocol should follow the methods outlined in the "Manual of Groundwater Sampling <br /> Procedures", Scalf, M.R., et al., 1981. National Water Well Associate, Worthington, Ohio, and the lab <br /> recommendations for specific sample collection. The methods used should be documented and included in the <br /> report to the DRMS. <br /> 3. Even though no"Points of Compliance"were expressly named,the current plan specified that the DRMS will be <br /> notified if the lab report indicates an exceedance at any of the wells sampled. The wells sampled include three <br /> (3) wells downgradient and two (2) wells upgradient of the Nix Mine located at the approximate permit <br /> boundary. <br /> 4. The apparent, but unconfirmed, exceedances for iron, nitrate, nitrite, nitrite+ nitrate, sulfate, and total coliforms <br /> are now noted in Table 1. A number of analytes were not requested from the lab or were not noted during <br /> sampling which has been noted in Table 1. Table 1 has been updated and reformatted to correct any errors. <br /> RMCC will schedule testing to confirm the exceedances from baseline monitoring,obtain results for any missing <br /> parameters and will report the results in an updated table to the Division prior to the May annual report. <br /> 5. RMCC agreed to confirm analytes that exceeded the most stringent set forth in Tables 1-4 of the Interim <br /> Narrative Standards with subsequent testing. The attached 1974 aerial photograph from USGS of the Nix Mine <br /> and surrounding area shows that historical Land use in the area since at least that time, and likely longer, has <br /> been flood irrigated farmland. As noted in the DeNitale letter, there are no domestic wells permitted though <br /> CDSS and only two(2) agricultural wells downgradient of the site. Given the historic and continuing agricultural <br /> land use in the area, the agricultural groundwater uses downgradient of the site, and the low potential for these <br /> pollutants to come from the mining process proposes to continue monitoring these analytes yearly and notifying <br /> DRMS per the approved plan if any of the analytes exceed the parameters developed by baseline monitoring. <br /> Confirmation testing of the exceedances observed in baseline monitoring should be performed prior to <br /> developing reporting parameters based on ambient conditions. <br /> 6. Graphic trendline data has been included. <br />