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<br />Because of the small quantity of mine water antici- <br />gated, discharge from ponds would normally be dominated <br />by water quality characteristics of disturbed area <br />runoff as described next. <br />Runoff from Disturbed Areas <br />' Overland runoff which passes over disturbed areas with- <br />in the permit area is channeled to one of the sedimen- <br />tation ponds. Sediment pond water may be discharged to <br />I the North Fork or stored for reuse within the mine area <br />when water rights are in priority. The quantity and <br />quality of effluent discharged from the sedimentation <br />ponds is described 'in the quarterly monitoring re- <br />ports. There was no discharge from the sedimentation <br />ponds during the period October through December, 1982. <br />The front discharge occurred from sedimentation pond <br />MB-1 on January 27, 1983 and again on February 16 and <br />March 7. Suspended solids average 34.7 mg/1 and total <br />iron averaged 1.57 mg/1. Discharge during this time <br />averaged 0.03 cfs. Dilution ratios, even for the <br />annual low flow of 36 cfs in the North Fork Gunnison <br />River still exceeded 1,160:1. Therefore, the incremen- <br />tal increase in suspended solids and total iron would <br />have been less than .03 mg/1 and 0.002 mg/i respec- <br />tively. <br />' During the quarter April-June, 1983, ponds MB-1 and MB- <br />2 both discharged. At no time during the quarter did <br />discharges exceed any of the NPDES permit limita- <br />tions. Flows in the North Fork during this quarter <br />' averaged approximately 2180 cfs. Suspended solids <br />measured in the North Fork Gunnison River on June 1, <br />1983 was 624 mg/1. The maximum suspended solids mea- <br />t sured in sediment pond discharges during the quarter <br />was 16 mg/1 from pond MB-2 on April 12. Total iron <br />measured in the North Fork on June 1, 1983 was 29.8 <br />mg/1. The maximum concentration of total iron in NPDES <br />discharges during the quarter was 0.57 mg/1 from MB-1 <br />on May 10. <br />During the quarter July-September, 1983, discharge <br />occurred from both MB-1 and MB-2. The discharge from <br />sedimentation pond MB-2 did exceed the average limits <br />from suspended solids during the quarter. The maximum <br />suspended solids in the discharge was 59 mg/1 measured <br />on September 12, 1983. The corresponding total iron <br />-31- <br /> <br />