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Ms. Christine E. Johnston 1992 AHR Response August 25, 1994 Page 2 3. The North Fork upper station is monitored for flow. This is the location of the USGS gaging station which is also monitored for water quality. Early in the monitoring program, it was determined that only one Flow station on the North Fork was necessary since the impact of the mine on river Flows would be negligible. However, water quality is monitored at the lower monitoring station since there could be measurable effects from mining operations. 4. Only one point was measured in late February, late May and late July at the Sylvester Gulch station ranging in flow from 0.1 to 0 efs. Even though these measurements exhibit a decrease in Flow during the spring snow melt, the runoff peak was probably missed between the February and May measurements because of the operational problems with the Flume being clogged with debris and/or overtopping the capacity of the flume. Comparison of daily Flows from acomparably-sized drainage at the Lick Creek flume, indicates that the peak flow was earlier during the month of May. As a result, flows on Sylvester Gulch appear to be appropriate for the season during which they were collected given the fact that the flows could vary considerably from day to day during storm water runoff events or warm periods which would increase Flow due to snow melt. The data from well GP-I indicates that the alluvial water table was at its peak during the measurement made during May. This is also appropriate for the season of the year. Subsequent comparison of this data should confirm this relationship. 5. Flow information will be incorporated with the surface water quality information found in Appendix D in future AHRs. Flow information from the samples acquired from the sediment ponds is not easily acquired. MCC monitors the total volume of discharges using flow gauges nn the discharge, but not the rate of discharge. The amount of water discharging from the end of the pipe typically exceeds the staffs capability to measure it. MCC will provide a Flow value in future AHRs based on a calculation derived from the quotient of the volume discharged and the lima period that the gate was open. SPRINGS: Data from field parameters indicated that some values were outside the minimum and maximum range. Samples sent to the laboratory require 20 l0 30 days to receive results and if a second sample were taken at [hat point in time, it would not correlate [o the prescribed sampling window or other samples previously obtained. As a result, MCC has applied for a revision to the plan to eliminate this second sampling requirement. MCC does not have an explanation as to why the minimum and maximum values were exceeded. GROUNDWATER: Page 8 of the AHR states "Some groundwater wells exhibited slightly changed conditions ...". The paragraph goes on to say "Most notably, the 1992 data indicates:" and nine (9) bullet items are discussed. These bullet items are the "changed conditions". 2. An error was made during data entry for water levels in well SOM 3g-H2. The hydrographs have been corrected and attached for replacement in the 1992 and 1993 AHRs. 3. On a yearly basis, MCC will measure the total depth of each well. The measurements along with any appropriate actions will be included in [he AHR.