months, resulting in an approximate 50% reduction in sampling effort (NUSCo 1984). 



Table 29. Estimated total number of winter flounder impinged on the intake screens of 



MNPS by season and year from October 1982 through September 1985 ^ 



* Estimates for Units 1 and 2 from October 1972 through December 1983 and for Unit 2 thereafter. 

 October through September 



Impingement estimates in themselves do not reflect absolute abundance of a species, but are related 

 to plant design and operational characteristics; time of day; and environmental variables such as water 

 temperature, wave height, wind direction and velocity, and precipitation (Grimes 1975; Landry and Strawn 

 1975; Lifton and Storr 1978). Severe windstorms combined with falling water temperatures particularly 

 have been correlated with increased impingement of fish at MNPS and elsewhere (Thomas and Miller 

 1977; Lifton and Storr 1978; NUSCo 1981a, 1983a, 1986a). Eleven instances were found when weekly 

 winter flounder impingement estimates exceeded 1,000 individuals; these samples were examined along 

 with available relevant meteorological data (Table 30). The impingement on these days made up a 

 considerable portion of seasonal and annual estimates. Six of the events occurred in 1979 and accounted 



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