discharges apparently have diminished. Lead is the only chemical showing concentrations in excess of 

 public health guideUnes. There are some sites where chemicals are at high concentrations (though not 

 necessarily threatening to marine organisms or man) and may be increasing. 



ACKNOWLEDGMENTS 



The NS&T Mussel Watch samples have been gathered and analyzed by the Battelle laboratories in 

 Duxbury, MA and in Sequim, WA; the Texas A&M University Geochemical and Environmental Re- 

 search Group in College Station, TX; and the LaJoUa, CA laboratory of Scientific Applications Inter- 

 national Corporation. 



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