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the mouth o; Stevens Gulch) generally hay lo::er ccncentrations than ::c-3a but <br />• not consistently so. Concentration., at i~r-3a and -:.a during September and October <br />Here distinctly hisher (5-30 times) that of the upper stations. <br />1'i:.nesota Cree}: - 3eLvlar sar,.rling o° 1;i:~;esota Cree}: be Can in earl,, :,ugus,,. <br />Concentrations Sro~ then thrcugh October v:ere wziSorray lox (< 1:-=0 ug~l). <br />Co~-~ar~SG^.5 <br />Freti~ous data from Ste•:ens Gulch rar.gad up to 11.,200 uS~l c,•ith indications <br />of the hiSt.er values o:lUinating from the mine site area. T7:e current ':ay- <br />Octo?~er samples had a similar range, but generally sho~;ed loser concentrations <br />than curing the early spring period. <br />Yr•e:-lous data on r:ar:ganese fm.^.. the :7orth Fork shoi;ed gen^_rall; lot•: concen- <br />trations (dissolved) •.;ith r..ost values ~j0 ug~'_; hoi;ever t~•:o hiEh values of 670 <br />• and 27b0 ug~i sere seen in }arch 1=73 sa^ples belt:; the rcuth of „terns Gulch <br />(;7F-4a). COP.S1dCr1n~; LnaL latter sa.^.,ples were of total manganese rather than <br />dissolved, the April-0ctober concentrations ::ere vahin the range oS pre:~ous <br />tialues and not as high as the one 2750 u%~1 concentration Sound in ;;arch. <br />Si;-nificance <br />r~.:isting state guidelines for dissolved m:.nsanese are 1000 ug,~l. Prcposed <br />Federal standards for manganese (total) area ::axinum of b000 and a 30-day averase <br />of 2;')00 ug~l. <br />In Stevens Gulch, four samples of the 22 sampling dates and exceeded the <br />1000 uE~l state guideline and ti:o samples exceeded the I,Oro ug~l federal r.,aximum. <br />T1:e control station had high corceatratiors (3,010 ug~l) the co_'lectio:: date the <br />• highest concentraticrs ,,rere Sound. HoH•ever greater concentratio.-is probabl;; carne <br />from the mine site area to give a net concentration of 13,100 ug~l tuo-thizds oS <br />the ~:ay down the Gulch. <br />3-25 <br />