Stewart 1982; Woodin 1982; Moeller et al. 1985) can strongly influence the abundance and composition 

 of infaunal communities. As a result, the structure of natural infaunal communities oscillates around 

 an equilibrium point and the range can only be established through long-term studies (Holland 1985). 



The sampling of infaunal communities to identify environmental impacts associated with construction 

 and operation of the Millstone Nuclear Power Station (MNPS) began in 1969, one year before start-up 

 of Millstone Unit 1, has continued interrupted since that time. Environmental changes associated with 

 construction and operation of MNPS include: bottom scour near the intake and discharge structures 

 caused by water currents; chemical and heavy metal additions to the water; dredging near the intake and 

 discharge structures and increased water temperatures due to cooling water discharge. To assess the 

 degree of impact of these power plant induced changes on infaunal communities, the MNPS benthic 

 monitoring program was designed to: 



(1). Describe infaunal community abundance and composition at subtidal and intertidal stations located 

 within and beyond areas influenced by operation and construction of the MNPS, 



(2). Identify spatial and temporal patterns in community structure and establish the extent and direction 

 of natural changes in these communities. 



(3). Evaluate whether any observed changes in infaunal communities were the result of construction 

 and/or operation of MNPS and; if so, assess their ecological significance. 



Since 1975, the long-term infaunal program has centered on assessment of impacts that might occur 

 during 2-unit operation. In recent years, additional short-term studies were implemented to provide data 

 that will be used to assess nearfield impacts that result from Unit 3 start-up. These studies included an 

 investigation of the infaunal community inhabiting the Millstone Discharge Quarry (Appendix BI-I) and 

 a study of infaunal organisms inhabiting the area of the discharge cut (Appendix BI-II). The following 

 report is intended to summarize results of the long-term sampling prior to the commercial operation of 

 Unit 3 (April 1986) and is intended to establish a baseline for assessing impacts that might occur during 

 3-unit operation at the Millstone facility. 



