ranging up to 9 hrs, then returned to ambient temperature and held for 

 five days. Low mortality was observed for silver sides and mummichogs 

 ( < 10% in most cases) . Winter flounder larvae less than 5 mm (pre- 

 metamorphosis) exhibited high mortality (29 to 89%) with increased 

 mortality at longer exposure times. Metamorphosed winter flounder 

 larvae ( > 5 mm) had virtually no mortality at exposures of as long as 

 9 hrs. 



Present Entrainment Program 



The present entrainment study was conducted by Normandeau Associates, 

 Inc. (NAI) beginning in July 1975 and includes collection of three 

 sequential replicate net tows (0.333-mm net, 1-m mouth, NAI- electronic 

 flow meters) at the Discharge on each of three days and three nights 

 weekly. Thus, eighteen entrainment ichthyoplankton samples have been 

 taken weekly to the present. Sampling began at the Discharge of Unit 2 

 in September 1975. Sampling is alternated weekly between both discharge 

 stations when plant operations permit. NUSCo staff has conducted the 

 entrainment ichthyoplankton studies since 1977. 



Bases for Present Entrainment Program 



This sampling frequency and technique was developed as the result 

 of an evaluation of the WHOI program (NUSCo 1976) and was adopted to 

 improve accuracy of sampling and sensitivity of subsequent analyses. 

 Several changes were made as a result of the evaluation. The TSK flow 

 meter was replaced by an NAI-Electronic Readout Box (ERB) flow meter 

 system which was accurate at low current velocities and could account 

 for potential reductions in flow due to net clogging (NUSCo 1976). The 



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