Callaway Nuclear Generating Station
|Location||Auxvasse Township, Callaway County, near Steedman, Missouri|
|Commission date||December 19, 1984|
|Construction cost||$5.919 billion (2007 USD)|
|Nuclear power station|
|Reactor supplier||Westinghouse (Unit 1)|
|Cooling source||Missouri River|
|Units operational||1 × 1,300 MW|
|Make and model||1 General Electric|
|Annual net output||9,372 GWh|
The Callaway Plant is a nuclear power plant located on a 5,228-acre (2,116 ha) site in Callaway County, Missouri, near Fulton, Missouri. It began operating on December 19, 1984. The plant, which is the state's only commercial nuclear unit, has one 1,190-megawatt Westinghouse four-loop pressurized water reactor and a General Electric turbine-generator. It is owned by the Ameren Corporation and operated by subsidiary Ameren Missouri.
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 population within 10 miles (16 km) of Callaway was 10,092, an increase of 3.8 percent in a decade, according to an analysis of U.S. Census data for msnbc.com. The 2010 population within 50 miles (80 km) was 546,292, an increase of 15.0 percent since 2000. Cities within 50 miles include Fulton (11 miles to city center), Jefferson City (26 miles to city center), and Columbia (32 miles to city center).
According to Ameren, Callaway produces about 19 percent of Ameren Missouri's power. In 2001, Callaway set a plant record for capacity utilization, producing 101.1 percent of its rated electrical output, ranking it among the world's top reactors, according to the Energy Information Administration. The plant produces 1,279 electrical megawatts (MWe) of net power, and has run continuously for over 500 days between refuelings. Callaway is one of 26 nuclear power plants in the United States to achieve a continuous run of over 500 days.
On November 19, 2005, its workers completed the replacement of all four steam generators in 63 days, 13 hours, setting a world record for a four-loop plant.
The cooling tower at Callaway is 553 feet (169 m) tall. It is 430 feet wide at the base, and is constructed from reinforced concrete. It cools approximately 585,000 US gallons (2,210,000 l; 487,000 imp gal) of water per minute when the plant is operating at full capacity, and about 15,000 US gallons (57,000 l; 12,000 imp gal) of water per minute are lost out the top from evaporation. Another 5,000 US gallons (19,000 l; 4,200 imp gal) of water are sent to the Missouri River as "blowdown" to flush solids from the cooling tower basin. All water lost through evaporation or blowdown is replaced with water from the river, located five miles from the plant. The temperature of the water going into the cooling tower is 125 °F (52 °C), and the tower cools it to 95 °F (35 °C). The tower is designed such that if it were to somehow topple over completely intact, it would not damage any of the critical plant structures.
Proposed Unit 2 and cancellation
On July 28, 2008, Ameren Missouri submitted an application to the U.S. Nuclear Regulatory Commission (NRC), seeking a Combined Construction and Operating License (COL) for a potential second unit. According to Thomas R. Voss, president and chief executive officer of Ameren Missouri, "Given projections for a nearly 30 percent increase in demand for power in Missouri in the next two decades, we believe we will need to build a large generating plant to be on line in the 2018–2020 timeframe." Ameren Missouri proposed building a 1,600-MW Areva Evolutionary Power Reactor (EPR).
In April 2009, the proposal was cancelled. A key stumbling block was a law barring utilities from charging customers for the interest accrued on the $6 billion loan required to build a new power plant prior to it producing electricity. The new nuclear plant would have cost at least $6 billion.
In April 2012 Ameren Missouri and Westinghouse Electric Company announced their intent to seek federal funding for a new generation of nuclear reactors to be installed at the Callaway site. The U.S. Department of Energy could provide up to $452 million in research and development funds to Westinghouse. The new reactors would be smaller and, claims have been made that they would be safer in design than any currently operating. Ameren Missouri would apply to license up five of the 225-megawatt reactors at the Callaway site, more than doubling its current electrical output.
In August 2015, all plans for further expansion of nuclear-powered electricity generation at the site were scrapped.  The previous month, Ameren announced new solar facilities would be constructed in Missouri. 
The Nuclear Regulatory Commission's estimate of the risk each year of an earthquake intense enough to cause core damage to the reactor at Callaway was 1 in 500,000, according to an NRC study published in August 2010. This was the lowest probability of any U.S. reactor.
- "EIA - State Nuclear Profiles". www.eia.gov. Retrieved 3 October 2017.
- "Archived copy". Archived from the original on 2006-10-02. Retrieved 2012-08-17.
- 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.
- Callaway Nuclear Plant well water samples have radioactivity, August 5, 2014 http://www.connectmidmissouri.com/news/story.aspx?id=1079567
- "Ameren Missouri Submits Combined Construction and Operating License Application for a Second Nuclear Generating Unit". Ameren. 2008-07-28. Retrieved 2008-07-29.
- "Missouri Nuclear Industry". Energy Information Administration. 2006-08-18. Retrieved 2008-12-30.
- "Callaway Nuclear Plant Returns to Service Following Refueling and Maintenance; Sets World Record for Steam Generator Replacement". Ameren. 2005-11-21. Retrieved 2008-07-29.
- Dan Yurman (2008-07-28). "Ameren files for 2nd reactor with NRC". Idaho Samizdat: Nuke Notes. Retrieved 2008-07-29.
- Nuke plant is, well, nuked. Not gonna happen
- Terry Ganey. AmerenUE pulls plug on project Columbia Daily Tribune, April 23, 2009.
- "Federal aid sought to build nuclear reactors in Missouri". The Kansas City Star. 2012-04-19. Retrieved 2012-04-20.
- 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.
- "Callaway Nuclear Plant, Missouri". U.S. Department of Energy (DOE). September 22, 2008. Retrieved 2008-11-14.
- "Callaway Pressurized Water Reactor". Operating Nuclear Power Reactors. NRC. February 14, 2008. Retrieved 2008-11-14.
- "Callaway, Unit 2 Application". New Reactors. NRC. October 31, 2008. Retrieved 2008-11-14.
- Ameren's information page for Callaway
- NRC Facility Info