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• The silver standard of 0.0001 ppm was too low for the accredited laboratory to provide consistent results below 0.0002 ppm. In 1992, the Colorado Department of Health raised the silver standard to 0.0008 ppm. Present levels of silver remain at <0.0002 ppm, well within the new criteria. Increased zinc concentrations have historically occurred during summer months, although not on an annual basis. Please refer to the attached chart showing zinc concentration levels over time. In the spring of 1992, the Colorado Department of Health reduced the permitted zinc level to 0.13 ppm for a monthly average. During the summer months of 1992, monthly averages exceeded the criteria for four consecutive months (0.26, 0.20, 0.135, and 0.14 ppm zinc). A citation was issued by the Health Department in regards to the four excursions. The discharge has been in compliance following the 0.14 ppm excursion. Discussions with the agency are ongoing to arrive at a compliance schedule for mitigation procedures for any future exceedances. The company is pursuing several alternatives to achieve compliance. Included in the Carlton Tunnel data are records recently obtained from the United States Geological Survey in Pueblo, Colorado. This data will further substantiate the Carlton Tunnel discharge data submitted on a monthly basis to the EPA and Colorado Department of Health. The USGS data also covers Wilson Creek which flows into Four-mile Creek downstream of the Carlton Tunnel Discharge. Wilson Creek data reflects the City of Victor wastewater effluent. The Cripple Creek data was taken below the discharge of that city's wastewater treatment plant. 2. The Areaua Gulch Surface Water monitoring site is located downstream of the Carlton Mill tailings ponds (1951-1961) and one-quarter mile upstream from the Arequa Gulch confluence with Cripple Creek. The five-year tabulation provides good baseline data for surface water below the proposed leach pad and waste rock storage area. Although the data shows an increase in total cyanide in 1990, the trend is downward while free and WAD cyanide levels remained low. 3. The Leachate Test Results represent tests made on spent pads which were subject to detoxification only by rain water and snow-melt draining through the pads to the pregnant ponds. Leach Pad No. 3 has experienced some spraying with pond water with no chemicals added to begin formal detoxification of that pad. The sample locations and test procedures are indicated in the attached data. The tests were conducted for the Globe Hill Leach Pad (M-77-367), Pad No. 3 (M-86-024), '76 Pad (M-77-367) and Pad A/Victor Mill Vat Leach Tails (M-81-134). The leachate tests were conducted under the TCLP criteria as shown. Future tests will be carried out under the TCLP test criteria 1312 solution 3 for cyanide wastes.