K) 



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u 



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In V 

 oo 



z 

 a 





iu>- 

 Si 



w 



fco 

 Pa: 

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JAN FEB. MAR APR MAY JUN JUL AUG SEP OCT NOV, DEC. 



COLUMBIA RIVER BELOW VANTAGE 



Average Monthly Woter Quality 



1954 - 1957 



FIG 21 



49 



