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RED CANYON MINE - 6 - September 3, 1985 Generally, when flows are high, conductivities are low. At both relatively high and low flows, magnesium, sodium and sulfate are high, however, they are most elevated during periods of high flow. An interesting note here is that the channel between points SP-B and SP-C is a losing reach. That is, during periods of base flow (fall through snowmelt) the sediment pond has discharged as much as 8.2 gal/min, yet at SP-C, a little ever 1,000 feet away, there will be no flow. The loss, if occurring at or near SP-B, could account for the elevated water level and increased specific conductivities at sediment pond piezometer P-1, as noted in the ground water section. Sample point SP-D is in the permit area on the Carbon Ditch. The ditch, which is located parallel to 2075 Road, flows substantially more water than the Rod Canyon Ditch. The water in the ditch is of much better quality than that at SP-C. The quality of the Carbon Ditch water appears to mirror that of local streams, being somewhat elevated in sulfate. The Nelson Ditch is monitored monthly for field parameters. This water is high in conductance for surface flow. Its pH varies from 7.4 to 8.3. The flow in this ditch was measured in February of 1983 at 150 gal/min. Five springs are to be monitored near the mine site. Monitoring of Spring No. 2 will be discontinued due to dilution from Williams Creek and irrigation return flows. No field parameters were reported for No. 2 and discharges have been reported as "normal". Spring No. 1, southwest of the mine, has a fairly constant yearly discharge of 23 to 33 gal/min. The conductivity (673) and low temperature (9°C) indicate that this spring may be bedrock controlled. Spring No. 3 varied in discharge from 6.7 gal/min in August, to 3.5 gal/min in mid-February. Likewise, Spring No. 4 shows a seasonal variation. This spring discharged a maximum of 30 gal/min in August, and dropped to 1.1 gal/min by mid-April. The seasonal change in discharge is indicative of a short, alluvial/colluvial flow system. Conductivity values (400 to 600)) tend to substantiate this. Spring No. 5, measured twice, is somewhat mysterious. It's high conductance (4,700) and low temperature (5oC) indicate a deep source. The flow from this spring, however, dropped from 15 gal/min to zero, between April and May of 1984. This spring should be indentified on the Hydrology Map. A discussion by the permittee may be in order here. Continued monthly monitoring is imperative.