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2002 water year. No flows were reported in Magpie Creek, Second Alkali Creek or at <br />the downstream monitoring point of Newlin Creek for the most recent period reported <br />(2001). Oak Creek reported flows only during the 2"d quarter (5-22-O1) of the most <br />recent reporting period (2001). <br />1. There will be temporary increases in runofffrom surface disturbance. <br />That is intuitive, but there is no confirmation. Certainly any increases have been minor <br />and of little overall effect. <br />2. There will be minor reductions in surface flows because of the sediment control <br />ponds. <br />This has not been significant overall. In the PHC of the permit, the total storage capacity <br />of the ponds is compazed to the total surface flow through the permit area, with a <br />maximum of 4.01 acre-feet of storage capacity representing 0.2% of the surface flow on <br />Newlin Creek. Even full to capacity, the amount of water retained in the ponds would <br />represent an insignificant reduction in the surface flows, as asserted in the PHC. There <br />were no discharges from the ponds during the 2002 water year. <br />3. There will be an alteration ofsurfaceflowpatterns. <br />This is an insignificant effect. <br />4. There will be changes in surface water chemistry. <br />See response to #5 below. <br />5. There will be increases in total dissolved solids (TDS) and some other constituents. <br />No data aze available from the most recent reporting period for Newlin Creek, Magpie <br />Creek or Second Alkali Creek, as they reported no flows in 2002. The perennial stream, <br />Oak Creek, is the one for which this prediction can be tested. Data exist for the upstream <br />site since 1997, and from the downstream location since 1983. Note that Oak Creek does <br />not flow through the mine site itself, but the loadout area. <br />Using the 2001 sampling, there appear to be changes in water chemistry from the <br />monitoring point upstream of the loadout to that downstream. Effects predicted in the <br />PHC are increases in conductivity and attendant TDS (from 570 mg/1 upstream to 730 <br />mg/1 downstream). There were very slight increases in other consiituents: in <br />bicarbonate (229 mg/1 to 242 mg/1, although probably close to the error limits); calcium <br />(from 90 to 100 mg/1), chloride (from 10 to 12 mg/1), magnesium (from 25.8 to 27.6 <br />mg/I); nitrogen (0.25 to 0.46 mg/1), and copper (0 to 0.46 mg/1). The most significant <br />increase was in sodium (51 to 330). <br />