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inconclusive without verification using some type of simulated pilot plant 

 testing 



• Compounds or classes of compounds that may be responsible for the mill's 

 chronic toxicity include residual chlorine, chlorinated organic compounds, 

 color or lignin fragmentation products, aldehydes, resinous compounds, 

 and sulfur compounds Residual peroxide from the future ECF bleaching 

 sequence may also contribute to toxicity Results indicate that KPC's 

 chronic toxicity is not related to a single compound 



• Major sources of chronic toxicity are thought to be the chlorine stage 

 filtrate, screen room effluent, hot caustic stage filtrate, evaporator 

 condensate, and in the future, the peroxide stage filtrate 



• Attempting to identify' the specific compound(s) responsible for toxicity has 

 proven to be a very inefficient process for reducing the mill's chronic 

 toxicity KPC will continue to seek a better understanding of the causes of 

 toxicity and will follow developments in this field Until cause-and-efFect 

 relationships are better documented, KPC will measure the chronic toxicity 

 levels for different combinations of process changes and wastewater 

 treatment steps in search of the best result that can be achieved, regardless 

 of a precise understanding of the chemistry involved Effect on final 

 eflHuent toxicity will be considered when selecting pollution prevention 

 alternatives. 



KPC is committed to reducing final effluent toxicity as defined by the test procedures 

 specified in KPC's NPDES permit and State water quality regulations Over the past two 

 years, KPC has performed a series of studies to identify efTluent streams and classes of 

 compounds which appear to impact chronic toxicity The pollution prevention study will 

 build on that work by exploring pollution prevention opportunities for those classes of 

 compounds identified in the earlier studies 



Spill Prevention and Containment 



Spill prevention measures have been developed and are aimed at addressing the following 

 materials: 



• pulping chemicals including cooking liquor, spent cooking liquor, and 

 magnesium oxide; 



• mineral acids; 



• caustic (sodium hydroxide), 



• polymers; 



• chemicals delivered and unloaded from rail cars, 



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