Nuclear reactor accidents in the United States

The United States Government Accountability Office reported more than 150 incidents from 2001 to 2006 of nuclear plants not performing within acceptable safety guidelines. According to a 2010 survey of energy accidents, there have been at least 56 accidents at nuclear reactors in the United States (defined as incidents that either resulted in the loss of human life or more than US$50,000 of property damage). The most serious of these was the Three Mile Island accident in 1979. Davis-Besse Nuclear Power Plant has been the source of two of the top five most dangerous nuclear incidents in the United States since 1979.^[1] Relatively few accidents have involved fatalities.^[2]

Erosion of the 6-inch-thick (150 mm) carbon steel reactor head, caused by a persistent leak of borated water, at the Davis-Besse Nuclear Power Plant.

Context of Nuclear Accidents

Globally, there have been at least 99 (civilian and military) recorded nuclear reactor accidents from 1952 to 2009 (defined as incidents that either resulted in the loss of human life or more than US$50,000 of property damage, the amount the US federal government uses to define major energy accidents that must be reported), totaling US$20.5 billion in property damages. The accidents involved meltdowns, explosions, fires, and loss of coolant, and occurred during both normal operation and extreme emergency conditions (such as droughts and earthquakes). Property damage costs include destruction of property, emergency response, environmental remediation, evacuation, lost product, fines, and court claims.^[2] Because nuclear reactors are large and complex, accidents onsite tend to be relatively expensive.^[3]

In the U.S., at least 56 nuclear reactor accidents have occurred.^[2] The most serious of these U.S. accidents was the Three Mile Island accident in 1979. According to the Nuclear Regulatory Commission, the Davis–Besse Nuclear Power Station has been the source of two of the top five most dangerous nuclear incidents in the United States since 1979.^[1]

The United States Government Accountability Office reported more than 150 incidents from 2001 to 2006 of nuclear plants not performing within acceptable safety guidelines. In 2006, it said: "Since 2001, the ROP has resulted in more than 4,000 inspection findings concerning nuclear power plant licensees' failure to fully comply with NRC regulations and industry standards for safe plant operation, and NRC has subjected more than 75 percent (79) of the 103 operating plants to increased oversight for varying periods".^[4]

History

The Atomic Energy Act of 1954 encouraged private corporations in the United States to build nuclear reactors and a significant learning phase followed with many early partial core meltdowns and accidents at experimental reactors and research facilities.^[5] This led to the introduction of the Price-Anderson Act in 1957, which was "an implicit admission that nuclear power provided risks that producers were unwilling to assume without federal backing".^[5]

Nuclear reactor accidents continued into the 1960s with a small test reactor exploding at the Stationary Low-Power Reactor Number One in Idaho Falls in January 1961 resulting in three deaths which were the first fatalities in the history of U.S. nuclear reactor operations.^[6] There was also a partial meltdown at the Enrico Fermi Nuclear Generating Station in Michigan in 1966.^[5]

The large size of nuclear reactors ordered during the late 1960s raised new safety questions and created fears of a severe reactor accident that would send large quantities of radiation into the environment. In the early 1970s, a highly contentious debate over the performance of emergency core cooling systems in nuclear plants, designed to prevent a core meltdown that could lead to the "China syndrome", received coverage in the popular media and technical journals.^[7]^[8]

In 1976, four nuclear engineers —three from GE and one from the Nuclear Regulatory Commission— resigned, stating that nuclear power was not as safe as their superiors were claiming.^[9]^[10]^[11]^[12] They testified to the Joint Committee on Atomic Energy that:

"the cumulative effect of all design defects and deficiencies in the design, construction and operations of nuclear power plants makes a nuclear power plant accident, in our opinion, a certain event. The only question is when, and where.^[9]

Three Mile Island Nuclear Plant Accident

President Jimmy Carter leaving Three Mile Island Nuclear Generating Station for Middletown, Pennsylvania, April 1, 1979

On March 28, 1979, equipment failures and operator error contributed to loss of coolant and a partial core meltdown of Unit 2's pressurized water reactor at the Three Mile Island Nuclear Power Plant in Pennsylvania.^[13] The scope and complexity of this reactor accident became clear over the course of five days, as a number of agencies at the local, state and federal levels tried to solve the problem and decide whether the ongoing accident required an emergency evacuation, and to what extent.

Cleanup started in August 1979 and officially ended in December 1993, with a total cleanup cost of about $1 billion.^[14] In his 2007 preliminary assessment of major energy accidents, Benjamin K. Sovacool, estimated that the TMI accident caused a total of $2.4 billion in property damages.^[15] The health effects of the Three Mile Island accident are widely, but not universally, agreed to be very low level.^[16]^[17]

The TMI accident forced regulatory and operational improvements on a reluctant industry, but it also increased opposition to nuclear power.^[18] The accident triggered protests around the world.^[19]

List of accidents and incidents

**Nuclear reactor accidents in the U.S.**^[3]^[20]
Date	Location	Description	Fatalities	Cost (in millions 2006 US$)	INES rating
November 29, 1955	Arco, Idaho, US	Power excursion with partial core meltdown at National Reactor Testing Station's EBR-1 Experimental Breeder Reactor I	0	5
July 26, 1959	Simi Valley, California, USA	Partial core meltdown at Santa Susana Field Laboratory's Sodium Reactor Experiment	0	32
January 3, 1961	Idaho Falls, Idaho, US	Steam explosion and meltdown results in three fatalities at National Reactor Testing Station's SL-1 Stationary Low-Power Reactor Number One	3	22	4
July 24, 1964	Charlestown, Rhode Island, USA	An error by a worker at a United Nuclear Corporation fuel facility led to an accidental criticality	1	??
October 5, 1966	Monroe, Michigan, USA	Sodium cooling system malfunctions at Enrico Fermi demonstration breeder reactor causing partial core meltdown	0	19
July 16, 1971	Cordova, Illinois, USA	An electrician is electrocuted by a live cable at the Quad Cities Unit 1 reactor on the Mississippi River	1	1
April 21, 1973	Pacific Ocean, 370 miles from Puget Sound	Primary coolant leak on board the USS Guardfish while underway^[21]	0	unknown
August 11, 1973	Covert Township, Michigan, USA	Steam generator leak at the Palisades Nuclear Generating Station causes manual shutdown of pressurized water reactor	0	10
March 22, 1975	Athens, Alabama, USA	Fire burns for seven hours and damages more than 1600 control cables for three nuclear reactors at Browns Ferry, disabling core cooling systems	0	240
November 5, 1975	Brownville, Nebraska, USA	Hydrogen gas explosion damages the Cooper Nuclear Facility's auxiliary building	0	13
June 10, 1977	Waterford, Connecticut, USA	Hydrogen gas explosion damages three buildings and forces shutdown of Millstone-1 Boiling Water Reactor	0	15
February 4, 1979	Surry, Virginia, USA	Surry Unit 2 shut down in response to failing tube bundles in steam generators	0	12
March 28, 1979	Middletown, Pennsylvania, US	Loss of coolant and partial core meltdown, see Three Mile Island accident and Three Mile Island accident health effects	0	2,400	5^[22]
November 22, 1980	San Clemente, California, USA	Worker cleaning breaker cubicles at San Onofre Pressurized Water Reactor contacts an energized line and is electrocuted	1	1
January 25, 1982	Ontario, New York, USA	Ginna Nuclear Generating Station (then operated by Rochester Gas & Electric now by Constellation Energy Nuclear Group) experiences a steam tube rupture, releasing radioactivity into the environment.	0	1
February 26, 1982	San Clemente, California, USA	Southern California Company shuts down San Onofre Unit 1 out of concerns about earthquake	0	1
March 20, 1982	Scriba, New York, USA	Recirculation system piping fails at Nine Mile Point Unit 1, forcing two year shutdown	0	45
March 25, 1982	Buchanan, New York, USA	Damage to steam generator tubes and main generator resulting in a shut down Indian Point Energy Center Unit 3 for more than a year	0	56
June 18, 1982	Seneca, South Carolina, USA	Feedwater heat extraction line fails at Oconee 2 Pressurised Water Reactor, damaging thermal cooling system	0	10
February 12, 1983	Forked River, New Jersey, USA	Oyster Creek Nuclear Generating Station fails safety inspection, forced to shut down for repairs	0	32
February 26, 1983	Fort Pierce, Florida, USA	Damaged thermal shield and core barrel support at St. Lucie Unit 1, necessitating 13-month shutdown	0	54
September 15, 1984	Athens, Alabama, US	Safety violations, operator error, and design problems force six year outage at Browns Ferry Unit 2	0	110
March 9, 1985	Athens, Alabama, US	Instrumentation systems malfunction during start-up, which led to suspension of operations at all three Browns Ferry Units	0	1,830
June 9, 1985	Oak Harbor, Ohio, US	Loss of feedwater event at Davis-Besse reactor after main pumps shut down and auxiliary pumps tripped due to operator error. NRC review determines site area emergency should have been declared	0	?
April 11, 1986	Plymouth, Massachusetts, US	Recurring equipment problems force emergency shutdown of Boston Edison's Pilgrim Nuclear Power Plant	0	1,001
December 9, 1986	Surry, Virginia, USA	Feedwater line-burst at Surry Nuclear Power Plant kills 4	4
March 31, 1987	Delta, Pennsylvania, US	Peach Bottom units 2 and 3 shutdown due to cooling malfunctions and unexplained equipment problems	0	400
July 15, 1987	Burlington, Kansas, USA	Safety inspector dies from electrocution after contacting a mislabeled wire at Wolf Creek Nuclear Generating Station	1	1
December 19, 1987	Scriba, New York, US	Malfunctions force Niagara Mohawk Power Corporation to shut down Nine Mile Point Unit 1	0	150
March 29, 1988	Burlington, Kansas, USA	A worker at the Wolf Creek Generating Station falls through an unmarked manhole and electrocutes himself when trying to escape	1	1
September 10, 1988	Surry, Virginia, USA	Refuelling cavity seal fails and destroys internal pipe system at Surry Unit 2, forcing 12-month outage	0	9
March 5, 1989	Tonopah, Arizona, USA	Atmospheric dump valves fail at Palo Verde Unit 1, leading to main transformer fire and emergency shutdown	0	14
March 17, 1989	Lusby, Maryland, US	Inspections at Calvert Cliff Units 1 and 2 reveal cracks at pressurized heater sleeves, forcing extended shutdowns	0	120
November 17, 1991	Scriba, New York, USA	Safety and fire problems force shut down of the FitzPatrick nuclear reactor for 13 months	0	5
April 21, 1992	Southport, North Carolina, USA	NRC forces shut down of Brunswick Units 1 and 2 after emergency diesel generators fail	0	2
February 3, 1993	Bay City, Texas, USA	Auxiliary feed-water pumps fail at South Texas Project Units 1 and 2, prompting rapid shutdown of both reactors	0	3
February 27, 1993	Buchanan, New York, USA	New York Power Authority shuts down Indian Point Energy Center Unit 3 after AMSAC system fails	0	2
March 2, 1993	Soddy-Daisy, Tennessee, USA	Equipment failures and broken pipes cause shut down of Sequoyah Unit 1	0	3
December 25, 1993	Newport, Michigan, USA	Shut down of Fermi Unit 2 after main turbine experienced major failure due to improper maintenance	0	67
14 January 1995	Wiscasset, Maine, USA	Steam generator tubes unexpectedly crack at Maine Yankee nuclear reactor; shut down of the facility for a year	0	62
May 16, 1995	Salem, New Jersey, USA	Ventilation systems fail at Salem Units 1 and 2	0	34
February 20, 1996	Waterford, Connecticut, US	Leaking valve forces shutdown Millstone Nuclear Power Plant Units 1 and 2, multiple equipment failures found	0	254^[23]
May 15, 1996	Morris, Illinois, US	Plunging water levels around the nuclear fuel in the reactor's core prompt shut down at Dresden Generating Station	0	?
September 2, 1996	Crystal River, Florida, US	Balance-of-plant equipment malfunction forces shutdown and extensive repairs at Crystal River Unit 3	0	384
September 5, 1996	Clinton, Illinois, USA	Reactor recirculation pump fails, prompting shut down of Clinton boiling water reactor	0	38
September 20, 1996	Seneca, Illinois, USA	Service water system fails and results in closure of LaSalle Units 1 and 2 for more than 2 years	0	71
September 9, 1997	Bridgman, Michigan, USA	Ice condenser containment systems fail at Cook Units 1 and 2	0	11
May 25, 1999	Waterford, Connecticut, USA	Steam leak in feed-water heater causes manual shutdown and damage to control board annunicator at the Millstone Nuclear Power Plant	0	7
September 29, 1999	Lower Alloways Creek Township, New Jersey, USA	Major Freon leak at Hope Creek Nuclear Generating Station causes ventilation train chiller to trip, releasing toxic gas and damaging the cooling system	0	2
February 15, 2000	Buchanan, New York, USA	NRC Alert issued after steam tube rupture Indian Point Unit 2^[24]	0	2
February 16, 2002	Oak Harbor, Ohio, US	Severe boric acid corrosion of reactor head forces 24-month outage of Davis-Besse reactor	0	605^[25]	3
January 15, 2003	Bridgman, Michigan, USA	A fault in the main transformer at the Donald C. Cook Nuclear Generating Station causes a fire that damages the main generator and back-up turbines	0	10
June 16, 2005	Braidwood, Illinois, USA	Exelon's Braidwood nuclear station leaks tritium and contaminates local water supplies	0	41
August 4, 2005	Buchanan, New York, USA	Entergy's Indian Point Nuclear Plant leaks tritium and strontium into underground lakes from 1974 to 2005		30
March 6, 2006	Erwin, Tennessee, USA	Nuclear Fuel Services plant spills 35 litres of highly enriched uranium, necessitating 7-month shutdown	0	98
September, 2009	Crystal River, Florida, USA	When cutting into Crystal River 3 Nuclear Power Plant containment building to create a large opening for the replacement of the Steam generator (nuclear power) the structure was severely cracked resulting in the permanent closure of the facility.	0	1,000+
February 1, 2010	Vernon, Vermont, US	Deteriorating underground pipes from the Vermont Yankee Nuclear Power Plant leak radioactive tritium into groundwater supplies	0	700
July 15, 2011	Morris, Illinois, US	Chemical leak of sodium hypochlorite restricted access to a vital area that houses plant cooling water pumps at Dresden Generating Station	0	?
January 30, 2012	Byron, Illinois, US	An Unusual Incident, the lowest of four NRC emergency status declarations, occurred. Loss of off-site power caused unit 2 to run a shut down cycle and release a safe, expected amount of tritium steam into the atmosphere.^[26]^[27]	0	Undetermined
March 31, 2013	Russellville, Arkansas, US	One worker was killed and two others injured when part of a generator fell as it was being moved at the Arkansas Nuclear One.	1	?
July 2016	Bridgman, Michigan, US	Heavy steam leak into the turbine building of D.C. Cook Nuclear Station	0	?
July 2018	Genoa, Wisconsin, US	La Crosse Boiling Water Reactor Deconstruction leak into Mississippi River	0	?

Nuclear Power Plant Safety

A clean-up crew working to remove radioactive contamination after the Three Mile Island accident.

Nuclear safety in the U.S. is governed by federal regulations issued by the Nuclear Regulatory Commission (NRC). The NRC regulates all nuclear plants and materials in the U.S. except for of nuclear plants and materials controlled by the U.S. government, as well those powering naval vessels.^[28]^[29]

The 1979 Three Mile Island accident was a pivotal event that led to questions about U.S. nuclear safety.^[30] Earlier events had a similar effect, including a 1975 fire at Browns Ferry, the 1976 testimonials of three concerned GE nuclear engineers, the GE Three. In 1981, workers inadvertently reversed pipe restraints at the Diablo Canyon Power Plant reactors, compromising seismic protection systems, which further undermined confidence in nuclear safety. All of these well-publicised events undermined public support for the U.S. nuclear industry in the 1970s and the 1980s.^[30]

Recent concerns have been expressed about the safety of nuclear reactors. In 2012, the Union of Concerned Scientists, which tracks ongoing safety issues at operating nuclear plants, found that "leakage of radioactive materials is a pervasive problem at almost 90 percent of all reactors, as are issues that pose a risk of nuclear accidents".^[31]

Following the Japanese Fukushima Daiichi nuclear disaster, according to Black & Veatch's annual utility survey that took place after the disaster, of the 700 executives from the US electric utility industry that were surveyed, nuclear safety was the top concern.^[32] There are likely to be increased requirements for on-site spent fuel management and elevated design basis threats at nuclear power plants.^[33]^[34] License extensions for existing reactors will face additional scrutiny, with outcomes depending on the degree to which plants can meet new requirements, and some of the extensions already granted for more than 60 of the 104 operating U.S. reactors could be revisited. On-site storage, consolidated long-term storage, and geological disposal of spent fuel is "likely to be reevaluated in a new light because of the Fukushima storage pool experience".^[33]

In October 2011, the Nuclear Regulatory Commission instructed agency staff to move forward with seven of the 12 safety recommendations put forward by the federal task force in July. The recommendations include "new standards aimed at strengthening operators' ability to deal with a complete loss of power, ensuring plants can withstand floods and earthquakes and improving emergency response capabilities". The new safety standards will take up to five years to fully implement.^[35]

References

^ ^a ^b Nuclear Regulatory Commission (2004-09-16). "Davis-Besse preliminary accident sequence precursor analysis" (PDF). Retrieved 2006-06-14. and Nuclear Regulatory Commission (2004-09-20). "NRC issues preliminary risk analysis of the combined safety issues at Davis-Besse". Retrieved 2006-06-14.
^ ^a ^b ^c Benjamin K. Sovacool. A Critical Evaluation of Nuclear Power and Renewable Electricity in Asia, Journal of Contemporary Asia, Vol. 40, No. 3, August 2010, pp. 379–380.
^ ^a ^b Benjamin K. Sovacool (2009). The Accidental Century – Prominent Energy Accidents in the Last 100 Years Archived 2012-08-21 at the Wayback Machine
^ United States Government Accountability Office (2006). "Report to Congress" (PDF). p. 4.
^ ^a ^b ^c Benjamin K. Sovacool. The costs of failure: A preliminary assessment of major energy accidents, 1907–2007, Energy Policy 36 (2008), p. 1808.
^ Perhaps the Worst, Not the First TIME magazine, May 12, 1986.
^ Walker, J. Samuel (2004). Three Mile Island: A Nuclear Crisis in Historical Perspective (Berkeley: University of California Press), pp. 10–11.
^ Wolfgang Rudig (1990). Anti-nuclear Movements: A World Survey of Opposition to Nuclear Energy, Longman, pp. 66–67.
^ ^a ^b Mark Hertsgaard (1983). Nuclear Inc. The Men and Money Behind Nuclear Energy, Pantheon Books, New York, p. 72.
^ Jim Falk (1982). Global Fission: The Battle Over Nuclear Power, Oxford University Press, p. 95.
^ The San Jose Three TIME, Feb. 16, 1976.
^ The Struggle over Nuclear Power TIME, Mar. 08, 1976.
^ World Nuclear Association (1999). Three Mile Island: 1979 Archived 2013-02-17 at the Wayback Machine Retrieved December 24, 2008.
^ "14-Year Cleanup at Three Mile Island Concludes". New York Times. August 15, 1993. Retrieved March 28, 2011.
^ Benjamin K. Sovacool. The costs of failure: A preliminary assessment of major energy accidents, 1907–2007, Energy Policy 36 (2008), p. 1807.
^ Mangano, Joseph (2004). Three Mile Island: Health study meltdown, Bulletin of the atomic scientists, 60(5), pp. 31 -35.
^ World Nuclear Association. Three Mile Island Accident Archived 2013-02-17 at the Wayback Machine January 2010.
^ Wellock, Thomas R. Three Mile Island: A Nuclear Crisis in Historical Perspective (Book review) The Historian, 22 September 2005.
^ Mark Hertsgaard (1983). Nuclear Inc. The Men and Money Behind Nuclear Energy, Pantheon Books, New York, p. 95 & 97.
^ Benjamin K. Sovacool. A Critical Evaluation of Nuclear Power and Renewable Electricity in Asia, Journal of Contemporary Asia, Vol. 40, No. 3, August 2010, pp. 393–400.
^ "Report: Nuclear sub suffers accident off Oregon in 1973".
^ "Appendix VI - IAEA international nuclear events scale (INES)". www.iaea.org. Archived from the original on 2011-05-30.
^ Chen, Fu-Chen; Jahanshahi, Mohammad R. (2018-03-27). "Video-based crack detection using deep learning and Nave Bayes data fusion". In Sohn, Hoon (ed.). Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2018. Vol. 10598. International Society for Optics and Photonics. pp. 105980J. Bibcode:2018SPIE10598E..0JC. doi:10.1117/12.2296772. ISBN 9781510616929. S2CID 173187747.
^ Bel, Hubert T. l. "Inspector General Report – Ind" (PDF). Office of the Inspector General (OIG), U.S. Nuclear Regulatory Commission (NRC).
^ Blade, Toledo. "Davis-Besse stirs again". Toledo Blade.
^ Coleman, Korva (January 31, 2012). "Illinois Nuclear Power Plant Shuts Down Unit After Power Loss". NPR. Retrieved 2024-01-26.
^ ABC7. "Byron nuclear plant loses power, reactor shuts down | ABC7 Chicago | abc7chicago.com". ABC7 Chicago. Retrieved 2024-01-26.{{cite web}}: CS1 maint: numeric names: authors list (link)
^ About NRC, U.S. Nuclear Regulatory Commission. Retrieved 2007-6-1.
^ Our Governing Legislation, U.S. Nuclear Regulatory Commission. Retrieved 2007-6-1.
^ ^a ^b Nathan Hultman and Jonathan Koomey (1 May 2013). "Three Mile Island: The driver of US nuclear power's decline?". Bulletin of the Atomic Scientists. 69 (3): 63–70. Bibcode:2013BuAtS..69c..63H. doi:10.1177/0096340213485949. S2CID 145756891.
^ Mark Cooper (2012). "Nuclear safety and affordable reactors: Can we have both?" (PDF). Bulletin of the Atomic Scientists.
^ Eric Wesoff, Greentechmedia. "Black & Veatch’s 2011 Electric Utility Survey." June 16, 2011. Retrieved October 11, 2011.
^ ^a ^b Massachusetts Institute of Technology (2011). "The Future of the Nuclear Fuel Cycle" (PDF). p. xv.
^ Mark Cooper (July 2011). "The implications of Fukushima: The US perspective". Bulletin of the Atomic Scientists. 67 (4): 9. doi:10.1177/0096340211414840. S2CID 146270304.
^ Andrew Restuccia (2011-10-20). "Nuke regulators toughen safety rules". The Hill. Archived from the original on 2012-01-14.