cut opening, and 67 species were reported from September 1984-September 1986, beginning one year after 

 the second cut opening. Proportions for the three periods were 43:25:32, 41:26:33, and 40:22:37, respectively; 

 noticeable is the decrease in browns and reds with a concomitant increase in the proportion of greens. 

 This shift in relative proportions in response to elevated water temperature was also seen in the quarry 

 collections, and will be discussed in the next section. 



The floristic changes noted at FE were localized, and not indicative of more widespread effects. 

 Overall, the flora of Greater Millstone Bight has remained stable over time, and is similar to those studied 

 elsewhere in New England by other researchers (Vadas 1972; Wilce et al. 1978; Schneider et al. 1979; 

 Mathieson et al. 1981). The NUEL qualitative collections are important for predicting and assessing the 

 impact of 3-unit operation. These studies permit the determination of the degree of variability in seasonal 

 and yearly species occurrence. Qualitative differences in species composition among stations or years (as 

 noted at FE after 1983), as compared to species composition at the reference sites, can signal power plant 

 influence. Analyses of the flora in the years after Unit 3 becomes operational should indicate whether 

 possible thermal effects will be within present bounds or will spread to other reference sites. 



Quarry Study 



Qualitative algal collections from the Millstone quarry permit characterization of sites exposed to a 

 wide range of water temperatures, from ambient temperature when all reactors are shut down, to 21 "C 

 above ambient, when all reactors are at fuU power. Water temperatures change in response to varying 

 reactor power levels. 



The overall quarry flora, composed of all species collected in the quarry or quarry cut, is similar but 

 not identical, to that of the NUEL rocky shore sampling stations reported in the previous section. Of the 

 118 species collected from the quarry or quarry cut, only 3 have not been collected at other NUEL 

 monitoring sites: Audouinella flexuosa, A. sagraenum, and Soroc.arpus micromorus. Those species found 

 at other sites but never in the quarry or the quarry cut are mostly cold-water reds, browns, and their 

 epiphytes. The relative proportion of reds, browns, and greens at the MNPS quarry (1979- 1986) was 46:21:33. 



Some of the similarity between the quarry flora and that of the reference stations is due to periods of 

 ambient water temperatures in the quarry as a resuU of periodic reactor shutdown. Schneider (1981) 



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