LaSalle County Nuclear Generating Station
|LaSalle County Nuclear Generating Station|
|Location||Brookfield Township, LaSalle County, near Seneca, Illinois|
|Commission date||Unit 1: January 1, 1984
Unit 2: October 19, 1984
|Licence expiration||Unit 1: April 17, 2022
Unit 2: December 16, 2023
|Architect(s)||Sargent & Lundy|
|Reactors operational||1 x 1138 MW
1 x 1150 MW
|Reactor supplier(s)||General Electric|
|Power generation information|
|Annual generation||18,980 GW·h|
|As of 2008-11-19|
LaSalle County Nuclear Generating Station, located 11 miles (18 km) southeast of Ottawa, Illinois serves Chicago and northern Illinois with electricity. The plant is owned and operated by the Exelon Corporation. Its Units 1 and 2 began commercial operation in August 1982 and April 1984, respectively.
It has two General Electric boiling water reactors. LaSalle's Unit 1 is capable of generating 1200 net megawatts, while Unit 2 is capable of generating 1200 net megawatts, together generating a total of 2,400 net megawatts which is enough electricity to support the electricity needs of more than two million average American homes. Instead of cooling towers, the station has a 2,058 acres (833 ha) man-made cooling lake, which is also a popular fishery — LaSalle Lake State Fish and Wildlife Area — managed by the Illinois Department of Natural Resources.
LaSalle County Station units 1 and 2 currently holds the world record top two spots for run time without shutting down for boiling water reactors, 739 and 712 days respectively. Both cycles were breaker to breaker.
Surrounding population 
The Nuclear Regulatory Commission defines two emergency planning zones around nuclear power plants: a plume exposure pathway zone with a radius of 10 miles (16 km), concerned primarily with exposure to, and inhalation of, airborne radioactive contamination, and an ingestion pathway zone of about 50 miles (80 km), concerned primarily with ingestion of food and liquid contaminated by radioactivity.
The 2010 U.S. population within 10 miles (16 km) of LaSalle was 17,643, an increase of 7.1 percent in a decade, according to an analysis of U.S. Census data for msnbc.com. The 2010 U.S. population within 50 miles (80 km) was 1,902,775, an increase of 22.6 percent since 2000. Cities within 50 miles include Joliet (34 miles to city center).
Site area emergency 
On February 20, 2006, a "site area emergency" was declared at the plant at 12:28 AM. This was the first SAE declared at a US nuclear plant since 1991. Workers were shutting down Unit 1 for refueling when the plant's turbine control system malfunctioned, SCRAMing the reactor. The reactor had been operating at 6 percent power output at the time. Plant instruments indicated three of 185 control rods used to shut down the reactor were not fully inserted triggering the emergency declaration. After a reset, the plant's instruments indicated that only one control rod was not fully inserted, not three. The emergency ended at 4:27 AM with no damage or release of radioactivity.
Post trip evaluations have confirmed that all control rods were fully inserted within four minutes of the reactor SCRAM. A review indicates the problem was with the indication sensors, and that all control rods were fully inserted immediately at the time of the reactor scram. Follow-up evaluations also demonstrated that even if the three subject control rods remained fully withdrawn in a cold shutdown condition, the reactor would have remained adequately shutdown.
Seismic risk 
The Nuclear Regulatory Commission's estimate of the risk each year of an earthquake intense enough to cause core damage to the reactor at LaSalle was 1 in 357,143, according to an NRC study published in August 2010.
- "LaSalle County Generating Station". Exelon. Retrieved 2008-11-20.
- Bill Dedman, Nuclear neighbors: Population rises near US reactors, msnbc.com, April 14, 2011 http://www.msnbc.msn.com/id/42555888/ns/us_news-life/ Accessed May 1, 2011.
- NRC Event Number 42348
- Bill Dedman, "What are the odds? US nuke plants ranked by quake risk," msnbc.com, March 17, 2011 http://www.msnbc.msn.com/id/42103936/ Accessed April 19, 2011.
- "LaSalle County Generating Station, Illinois". Energy Information Administration, U.S. Department of Energy (DOE). August 22, 2008. Retrieved 2008-11-20.
- "La Salle 1 Boiling Water Reactor". Operating Nuclear Power Reactors. U.S. Nuclear Regulatory Commission (NRC). February 14, 2008. Retrieved 2008-11-20.
- "La Salle 2 Boiling Water Reactor". Operating Nuclear Power Reactors. NRC. February 14, 2008. Retrieved 2008-11-20.