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<br />`J <br />i~ <br />2. Surface k'a ter Site SW-S2-2 <br />This site is the furthest Downs treart: surface water site in the Little Grassy and Grassy <br />Creek drains Des prior to exiting the permit area. Therefore, it is the most significant <br />monitoring site with respect to showing the cumuletf ve effects of mininy in this area. <br />Review of the hydrograph of monthly flow readin os shows slightly less runoff this year <br />than that in 1985. Peak flow (from CSG data) was between E.0 to 14 cis ir, the spring of <br />1986 (brush washed onto the CSG made it hard to define a precise high water line). Peak <br />florv was 28 cfs in the spring of 1965. Peak flows from CSG data are measured upstream of <br />the NPDES 003 discharge (the only straight stretch of stream in the vicinity). Monthly <br />instantaneous flow data is cetermined by adding flow at the CSC site to the flow of NPDES <br />003. Water quality samples are taken below the discharge of NPDES 003 (see Exhibit 7-2 ). <br />Since SW-52-2 monitors the major drainage leaving the mine area, a comparison to EPA <br />criteria for livestock and irrigation is appropriate (see Table 13 ). Cnly total iron and <br />total manganese exceeded recommended limits, rvhile their respective dissolved constituents <br />were below the limits. Receiving stream standards (see Table 21) for Grassy Creek <br />(Segment 12) consists only of dissolved oxygen, coliform, and pH, of which only pH is <br />currently being analyzed. the pH values at this site fall within those limits. No <br />irrigation is currently practical on Gr as:~y Creek downs tream,of the mine. <br />D. S rings <br />Four natural springs were monitored in the fall of 1986: Springs #1, 2, 3, and 5 as shown <br />on Exhibit 7-2. Spring #4 was dropped per a letter from Sandy Emrich, CM LRD, to Tom <br />Wainwright, PCC, dated April 26, 1964. Item 7 in this letter requests monitoring only <br />springs within the permit boundary (see also Page 7-10-26 of Seneca II Mine Mid-Term <br />Review Revision). In addition, per a September 26, 1985 memo from Steven Renner, CMLRD, <br />to Steve Var diman, PCC, springs on reclaimed land (i. e., spoils springs) should be located <br />and monitored for flow. If flow exceeds 3 gpm, the spring should be analyzed for field <br />parameters. Five such spoils springs were located in November 1985. Two more spoil <br />springs were located in October 1986 and will be inclUtled in this report. <br />1. Natural Spring #5 <br />This spring is located in the Cow Camp Creek drainage but is, due to its location, <br />unlikely to be disturbed by mining. Flow was so low (0.02 gpm) that a lab sample could <br />not practically been taken; however, field parameters were measured. A 19E5 analysis <br />shows this water to be a maone si um sulfate type wi ih an extremely high TDS value of 14,200 <br />SO <br />