Fish Return Survival Studies Conducted at the Brunswick Nuclear Station, Southport, NC

The Brunswick Nuclear Station is located near the mouth of the Cape Fear River adjacent to Southport, North Carolina.  The Station consists of two nuclear generating units with a combined generating capacity of 1,875 MW.  Once-through cooling water is withdrawn from the Cape Fear River Estuary and discharged to the Atlantic Ocean.   Several intake modifications to reduce entrainment and impingement of organisms including modified Ristroph traveling screens and a 4000 ft (1,219 m) long fiberglass return flume were installed during 1983.  Additionally, 1–mm fine mesh screens were required on two of the four traveling screens per unit.  Studies were conducted from 1983-1987 to determined survival rates of the numerically dominant organisms that were returned to the Cape Fear River Estuary via the fish return system. Survival rates varied with species, size class, and traveling-screen rotation speed.  Survival was generally greater for larger size classes.  Survival rates of entrainable sized organisms were generally greater for faster traveling-screen rotation speeds compared to slower rotation speeds.  Overall survival rates ranged from approximately  < 5% for bay anchovy to > 90% for penaeid shrimp and blue crab.