(9) Summary of Test Results . Figure 3-84 shows the salinity 

 distribution of the bay system at the time of peak salinities for the 

 low inflow year with Southwest Pass open; Figure 3-85 shows the salinity 

 distribution at the time of peak salinity under similar inflow conditions 

 with the pass closed. Data presented in these two figures show that 

 closure of Southwest Pass reduced the maximum salinity along the west 

 side of Vermilion Bay and near the mouth of the Vermilion River from 

 about 15.0 to about 2.0 parts per thousand, or a reduction in maximum 

 salinity of almost 90 percent. The time of maximum salinity at the loca- 

 tion was also delayed from September to January (not shown in the figures) , 

 which would cause the time of occurrence of maximiom salinity to be delayed 

 until well after the end of the irrigation season instead of occurring 

 within the irrigation season. As a result, the salinity reduction 

 afforded by the plan in the critical irrigation season was greater than 

 90 percent. Although this plan has not been constructed in nature, the 

 model tests have demonstrated the benefits that would accrue to irriga- 

 tion interests. 



1. Thermal Pis charges- -James River . 



(1) Project . Construction of a nuclear power generating plant. 



(2) Reference . Pritchard (1967). 



(3) Laboratory . WES (physical model tests); Pritchard-Carpenter, 

 Consultants (collection and analysis of model data) . 



(4) Test Period of Physical Model . July and October 1966. 



(5) Problem . The Virginia Electric and Power Company was con- 

 structing the Surry Nuclear Power Station on the James River estuary. 

 The construction site is located approximately 30 miles above the mouth 

 of the James River at Old Point Comfort and 55 miles below Richmond, 

 Virginia. Hog Point is the northernmost point of a peninsula formed by 

 a large bend in the James River estuary (Fig. 3-86). The site of the 

 power station extends across the central part of the peninsula, the river 

 forming both the eastern and western boundaries of the site. The penin- 

 sula to the north of the site is a low-lying area of tidal marshes, tidal 

 channels, and islands which serve as a wildfowl refuge, and terminates at 

 Hog Point. 



A design of the cooling water discharge system was necessary to mini- 

 mize the impact of the waste heat on the estuarine environment (particu- 

 larly the nearby seed oysterbeds) and to minimize the return of waste 

 heat to the cooling water intake. The cooling water intake and discharge 

 were to be located on opposite sides of Hog Point. 



(6) Purpose of Model Study . The study was conducted to deter- 

 mine the probable effect of the discharge of waste heat from the con- 

 denser cooling water at the Surry Nuclear Power Station on the distribu- 

 tion of temperature in the adjacent James River estuary. 



