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mine year with the exception of NPDES site 001. Dam #8 failed on <br />• February 11, 1987, partially washing out the Parshall Flume at site <br />001. Maximum flow for this period was 4465 gpm. Recorded flows for <br />site 001 from February 11 through 26 were taken using volumetric <br />measurements at the outfall. Although the flume was reset and <br />operational on February 26, the actual amount of flow discharging <br />through site 001 shows a varied amount of baseflow included within the <br />recorded flows from seeps and ground water upstream of the flume. <br />This baseflow varied between 9 gpm during low flow periods and 36 gpm <br />when higher heads exist in Dam #8. During periods of no discharge <br />from the dam, a flow of approximately 9 gpm has been observed. <br />Average flow during the period presented in Figure C-3 was 152.1 gpm. <br />Low flow periods on Figure C-3 actually represent zero discharge, but <br />show some flow, as previously mentioned. <br />• NPDES site 002 (No Name Gulch) recorded very high flows of 846 <br />gpm and 825 gpm and overall average flow of 85.2 gpm during the period <br />shown in Figure C-4. Discharges varied throughout the period, as <br />Figure C-4 shows. No data was available near January 1 through the <br />middle of March, 1987 due to winter conditions. <br />The lOYR/24HR Coyote site flow versus time plot is presented in <br />Figure C-5. Discharges through the flume are presented by the peaks <br />seen on Figure C-5. No data was available from late 1986 to May 1987. <br />The 1970 gpm peak was due to pumping a local spoil pond for <br />dewatering. Average flow was 119.5 gpm during the period; but because <br />of silting in the stilling well recorder after pumping, some error in <br />recorded flows is most likely. <br />• <br />4-2 <br />