View source for Davis–Besse Nuclear Power Station

{{Short description|Nuclear power plant in Ottawa County, Ohio, United States}}
{{Use mdy dates|date=January 2025}}
{{Infobox power station
| name = Davis–Besse Nuclear Power Station
| name_official =
| image = David Besse NPP-2.jpg
| image_caption = The Davis–Besse NPP (NRC image)
| image_alt = The Davis–Besse NPP (NRC image)
| location_map_alt =
| coordinates = {{coord|41|35|48|N|83|5|11|W|region:US-OH_type:landmark|display=inline,title}}
| country = United States
| location = [[Carroll Township, Ottawa County, Ohio]], near [[Oak Harbor, Ohio|Oak Harbor]]
| status = O
| construction_began = September 1, 1970
| commissioned = July 31, 1978
| decommissioned =
| cost = $2.221 billion (2007 USD)<ref>{{cite web|title=EIA - State Nuclear Profiles|url=https://www.eia.gov/nuclear/state/archive/2010/ohio/|website=www.eia.gov|access-date=October 3, 2017|language=en}}</ref> (${{format price|{{Inflation|US-GDP|2.221e9|2007}}}} in {{Inflation-year|US-GDP}} dollars{{Inflation-fn|US-GDP}})
| owner = [[Vistra Corp|Vistra]]
| operator = [[Vistra Corp|Vistra]]
<!------------------------- NUCLEAR POWER STATIONS -->| np_reactor_type = PWR
| np_reactor_supplier = [[Babcock & Wilcox]]
| np_fuel_type =
| np_fuel_supplier =
| ps_cogeneration =
| ps_cooling_source = [[Lake Erie]]
| ps_cooling_towers = 1 × [[Natural Draft]]
<!------------------------- GENERAL -->| ps_units_operational = 1 × 894 MW
| ps_units_manu_model = [[Babcock & Wilcox|B&W]] RLP (DRYAMB)
| ps_units_uc =
| ps_units_planned =
| ps_units_cancelled = 2 × 910 MW
| ps_units_decommissioned =
| ps_thermal_capacity = 1 × 2817 MW<sub>th</sub>
| ps_heating_capacity =
| ps_electrical_capacity = 894
| ps_electrical_cap_fac = 100.57% (2017)<br />70.70% (lifetime)
| ps_storage_capacity =
| ps_annual_generation = 7779 GWh (2021)
| website = [https://web.archive.org/web/20171003124618/https://www.firstenergycorp.com/content/fecorp/about/generation_system/FENOC/davis-besse.html Davis-Besse]
| extra =
}}
[[File:Davis-Besse Nuclear Power Station cooling tower (4183).jpg|thumb|Davis–Besse Nuclear Power Station's cooling tower in July 2015]]

'''Davis–Besse Nuclear Power Station''' is an 894 megawatt ([[megawatt|MW]]) [[nuclear power plant]], located northeast of [[Oak Harbor, Ohio]], United States. It has a single [[pressurized water reactor]]. Davis–Besse is operated by [[Vistra Corp]].

Throughout its operation, Davis–Besse has been the site of several [[Nuclear and radiation accidents and incidents|safety incidents]] that affected the plant's operation. According to the [[Nuclear Regulatory Commission]] (NRC), Davis–Besse has been the source of two of the top five most dangerous [[Nuclear safety in the United States|nuclear incidents in the United States]] since 1979.<ref name="nrc.gov">{{cite web|author=Nuclear Regulatory Commission |date=September 16, 2004 |title=Davis–Besse preliminary accident sequence precursor analysis |url=https://www.nrc.gov/reactors/operating/ops-experience/vessel-head-degradation/news/2004/09-16-04-ml0426005320.pdf |access-date=June 14, 2006 |author-link=Nuclear Regulatory Commission }} and {{cite web|author=Nuclear Regulatory Commission |date=September 20, 2004 |title=NRC issues preliminary risk analysis of the combined safety issues at Davis–Besse |url=https://www.nrc.gov/reading-rm/doc-collections/news/2004/04-117.html |access-date=June 14, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20061003054919/http://www.nrc.gov/reading-rm/doc-collections/news/2004/04-117.html |archive-date=October 3, 2006 |author-link=Nuclear Regulatory Commission }}</ref> The most severe occurring in March 2002, when maintenance workers discovered [[corrosion]] had eaten a [[American football|football]]-sized hole into the reactor vessel head.<ref name=nrc2009/><ref>{{cite web |url=http://www.gao.gov/new.items/d061029.pdf |title=Report to Congress |author=United States Government Accountability Office |year=2006 |page=1 }}</ref> The NRC kept Davis–Besse shut down until March 2004, so that FirstEnergy was able to perform all the necessary maintenance for safe operations. The NRC imposed an over $5 million fine, its largest fine ever to a nuclear power plant, against FirstEnergy for the actions that led to the corrosion. The company paid an additional $28 million in fines under a settlement with the [[United States Department of Justice]] (DOJ).<ref name=nrc2009/>

Davis–Besse was expected to close in 2020 as it is no longer profitable to run when competing against natural gas plants.<ref>{{cite news|first=John|last=Funk|title=FirstEnergy Solutions will close its nuclear power plants, but is silent on bankruptcy restructuring|url=http://www.cleveland.com/business/index.ssf/2018/03/firstenergy_solutions_will_clo.html|work=[[The Plain Dealer]]|location=Cleveland, Ohio|date=March 28, 2018|access-date=March 29, 2018 | quote=During months of hearings, the company argued that its uncompetitive old coal and nuclear plants would become competitive once the price of natural gas increased. And at that point, customers would see credits on their monthly bills, they argued. Opponents cited federal predictions that natural gas would stay cheap for decades and customers would just keep on paying higher rates.}}</ref> Plans were updated indicating possible shut down by May 31, 2020.<ref>{{cite news|title=Davis-Besse nuclear reactor close to full power|url=https://www.toledoblade.com/local/environment/2019/01/15/davis-besse-nuclear-plant-reactor-close-being-fully-operational/stories/20190115127|last=Henry|first=Tom|newspaper=The Blade|date=January 15, 2019|access-date=February 3, 2019}}</ref> However, Ohio House Bill 6 was signed into law in July 2019 which added a fee to residents' utility bills that funded subsidies of $150&nbsp;million per year to Davis–Besse and the [[Perry Nuclear Generating Station]] to keep both plants operational.<ref name=rescind>{{cite web|url=https://www.thenews-messenger.com/story/news/local/2019/07/24/firstenergy-solutions-announces-refuel-davis-besse-nuclear-power-station/1822494001/|title=FirstEnergy Solutions announces it will refuel at Davis-Besse| first=Daniel | last=Carson | newspaper=Fremont News-Messenger|date=July 24, 2019|access-date=July 25, 2019}}</ref><ref>{{cite web|url=https://www.cleveland.com/open/2019/07/nuclear-bailout-bill-passes-ohio-legislature.html|title=Nuclear bailout bill passes Ohio legislature, signed by Gov. Mike DeWine| first=Jeremy | last=Pelzer |newspaper=The Plain Dealer|date=July 23, 2019|access-date=July 25, 2019}}</ref>{{r | NPR_1 }} The bill was alleged to be part of the [[Ohio nuclear bribery scandal]] revealed by the [[United States Department of Justice]] (DOJ) in July 2020.<ref>{{cite court|url=https://assets.documentcloud.org/documents/6999130/Ohio-House-complaint.pdf|litigants=U.S. v. Larry Householder, Jeffery Longstreth, Neil Clark, Matthew Borges, Juan Cespedes, and Generation Now|court=S.D. Ohio|date=July 16, 2020|access-date=August 3, 2020}}</ref><ref name=NPR_1 > {{ cite news | url=https://www.npr.org/2020/07/21/893493224/ohio-house-speaker-arrested-in-connection-to-60-million-bribery-scheme | title=Ohio House Speaker Arrested In Connection With $60 Million Bribery Scheme | last=Wamsley | first=Laura | newspaper=[[NPR]] | date=July 21, 2020 | access-date=July 21, 2020 | quote=Last year's nuclear bailout law tacked on a charge to residents' power bills, sending $150 million a year to the nuclear power plants. They are owned by the company Energy Harbor, which was previously known as FirstEnergy Solutions. }}</ref>

== Location and history ==
The power station is located on the southwest shore of [[Lake Erie]] about {{convert|10|mi}} north of [[Oak Harbor, Ohio]] and is on the north side of Highway&nbsp;2 just east of Highway&nbsp;19 on a {{convert|954|acre|ha|adj=on}} site in the Carroll Township. The plant only utilizes {{convert|221|acre|ha}}, with {{convert|733|acre|ha}} devoted to the [[Ottawa National Wildlife Refuge]]. The entrance to the [[Magee Marsh Wildlife Area]]<ref>[http://www.ohiodnr.com/Home/wild_resourcessubhomepage/WildlifeAreaMapsLandingPage/NorthwestOhioWildlifeAreaMaps/MageeMarshWildlifeArea/tabid/19778/Default.aspx] – Magee Marsh Wildlife Area</ref> is approximately 5 miles east of the power station. The official name according to the U.S. [[Energy Information Administration]] is the Davis–Besse Nuclear Generating Station.  It is the 57th commercial power reactor to commence building in the [[United States of America]] (construction began on September 1, 1970) and the 50th to come on-line July 31, 1978.<ref>{{cite web | author=Energy Information Administration | date=November 2004 | title=U.S. Nuclear Reactor List – Operational | format=XLS | url=http://www.eia.doe.gov/cneaf/nuclear/page/nuc_reactors/operational.xls | access-date=June 14, 2006 | archive-url=https://web.archive.org/web/20110227224915/http://www.eia.doe.gov/cneaf/nuclear/page/nuc_reactors/operational.xls | archive-date=February 27, 2011 | url-status=dead | author-link=Energy Information Administration }}</ref> The plant was originally jointly owned by [[Cleveland Electric Illuminating]] (CEI) and [[Toledo Edison]] (TE) and was named for former TE Chairman John K. Davis and former CEI Chairman Ralph M. Besse.

[[File:Davis-Besse ReactorHeadInspection.jpg|thumb|The reactor head under inspection]]

Unit One is an 879&nbsp;MWe pressurized water reactor supplied by [[Babcock & Wilcox]].  The reactor was shut down from 2002 until early 2004 for safety repairs and upgrades. In 2012 the reactor supplied 7101.700&nbsp;GWh of electricity.<ref>IAEA PRIS database http://www.iaea.org/PRIS/CountryStatistics/ReactorDetails.aspx?current=676</ref>

In 1973, two more reactors were also ordered from Babcock & Wilcox. However, construction on Units Two and Three never commenced, and these two units were officially canceled in 1981.<ref>{{Cite web|url=http://local.ans.org/mi/michigan-plants/ohio-facilities/24-davis-besse|title = Davis-Besse}}</ref>

== Electricity production ==
{| class="wikitable"
|+'''Generation ('''[[Kilowatt-hour|MWh]]''') of Davis-Besse Nuclear Power Station'''<ref>{{Cite web |title=Electricity Data Browser |url=https://www.eia.gov/electricity/data/browser/#/plant/6149/?freq=M&pin= |access-date=January 7, 2023 |website=www.eia.gov}}</ref>
!Year
!Jan
!Feb
!Mar
!Apr
!May
!Jun
!Jul
!Aug
!Sep
!Oct
!Nov
!Dec
!Annual (Total)
|-
!2001
|<small>659,778</small>
|<small>601,935</small>
|<small>655,630</small>
|<small>634,920</small>
|<small>658,726</small>
|<small>633,332</small>
|<small>648,532</small>
|<small>655,159</small>
|<small>637,346</small>
|<small>624,363</small>
|<small>615,007</small>
|<small>659,590</small>
!7,684,318
|-
!2002
|<small>664,299</small>
|<small>257,171</small>
|<small>-4,123</small>
|<small>-4,136</small>
|<small>-3,264</small>
|<small>-3,616</small>
|<small>-3,665</small>
|<small>-1,052</small>
|<small>-2,868</small>
|<small>-2,879</small>
|<small>-2,910</small>
|<small>-2,865</small>
!890,092
|-
!2003
|<small>-3,229</small>
|<small>-3,011</small>
|<small>-3,515</small>
|<small>-3,314</small>
|<small>-4,344</small>
|<small>-4,228</small>
|<small>-7,123</small>
|<small>-4,102</small>
|<small>-18,422</small>
|<small>-5,997</small>
|<small>-3,193</small>
|<small>-9,682</small>
!-70,160
|-
!2004
|<small>-22,203</small>
|<small>-24,463</small>
|<small>48,988</small>
|<small>616,820</small>
|<small>654,538</small>
|<small>635,521</small>
|<small>656,635</small>
|<small>550,253</small>
|<small>636,241</small>
|<small>662,232</small>
|<small>644,274</small>
|<small>663,959</small>
!5,722,795
|-
!2005
|<small>333,513</small>
|<small>395,132</small>
|<small>669,279</small>
|<small>640,760</small>
|<small>661,392</small>
|<small>635,065</small>
|<small>647,321</small>
|<small>651,779</small>
|<small>633,822</small>
|<small>591,221</small>
|<small>632,360</small>
|<small>664,441</small>
!7,156,085
|-
!2006
|<small>663,170</small>
|<small>593,863</small>
|<small>95,136</small>
|<small>20,897</small>
|<small>641,900</small>
|<small>625,721</small>
|<small>662,730</small>
|<small>662,215</small>
|<small>574,727</small>
|<small>672,039</small>
|<small>489,047</small>
|<small>670,121</small>
!6,371,566
|-
!2007
|<small>668,923</small>
|<small>601,820</small>
|<small>639,963</small>
|<small>643,498</small>
|<small>630,043</small>
|<small>640,493</small>
|<small>661,833</small>
|<small>658,993</small>
|<small>629,766</small>
|<small>663,599</small>
|<small>646,539</small>
|<small>620,332</small>
!7,705,802
|-
!2008
|<small>-6,155</small>
|<small>297,934</small>
|<small>662,611</small>
|<small>637,980</small>
|<small>668,821</small>
|<small>631,100</small>
|<small>667,935</small>
|<small>674,678</small>
|<small>654,173</small>
|<small>682,609</small>
|<small>662,497</small>
|<small>589,102</small>
!6,823,285
|-
!2009
|<small>684,652</small>
|<small>617,619</small>
|<small>680,913</small>
|<small>264,381</small>
|<small>679,928</small>
|<small>652,887</small>
|<small>675,845</small>
|<small>674,620</small>
|<small>654,194</small>
|<small>681,912</small>
|<small>659,961</small>
|<small>682,700</small>
!7,609,612
|-
!2010
|<small>681,476</small>
|<small>561,079</small>
|<small>-952</small>
|<small>-1,365</small>
|<small>-754</small>
|<small>17,204</small>
|<small>669,076</small>
|<small>672,403</small>
|<small>654,037</small>
|<small>679,747</small>
|<small>569,433</small>
|<small>683,708</small>
!5,185,092
|-
!2011
|<small>530,909</small>
|<small>608,350</small>
|<small>679,484</small>
|<small>649,596</small>
|<small>674,584</small>
|<small>650,651</small>
|<small>669,594</small>
|<small>670,660</small>
|<small>645,742</small>
|<small>-1,655</small>
|<small>-1,643</small>
|<small>552,625</small>
!6,328,897
|-
!2012
|<small>682,506</small>
|<small>640,509</small>
|<small>676,545</small>
|<small>657,443</small>
|<small>111,026</small>
|<small>368,266</small>
|<small>671,108</small>
|<small>674,097</small>
|<small>654,386</small>
|<small>678,297</small>
|<small>621,933</small>
|<small>677,776</small>
!7,113,892
|-
!2013
|<small>680,984</small>
|<small>615,339</small>
|<small>681,159</small>
|<small>658,601</small>
|<small>676,769</small>
|<small>627,419</small>
|<small>399,908</small>
|<small>672,379</small>
|<small>652,538</small>
|<small>676,252</small>
|<small>658,784</small>
|<small>679,696</small>
!7,679,828
|-
!2014
|<small>664,720</small>
|<small>-1,310</small>
|<small>-1,933</small>
|<small>-2,049</small>
|<small>488,603</small>
|<small>652,873</small>
|<small>675,643</small>
|<small>674,824</small>
|<small>655,160</small>
|<small>680,229</small>
|<small>660,600</small>
|<small>681,809</small>
!5,829,169
|-
!2015
|<small>682,138</small>
|<small>615,646</small>
|<small>679,650</small>
|<small>657,153</small>
|<small>592,037</small>
|<small>653,796</small>
|<small>674,575</small>
|<small>675,160</small>
|<small>642,915</small>
|<small>679,625</small>
|<small>658,375</small>
|<small>682,821</small>
!7,893,891
|-
!2016
|<small>627,509</small>
|<small>544,477</small>
|<small>417,821</small>
|<small>-752</small>
|<small>457,391</small>
|<small>646,852</small>
|<small>667,664</small>
|<small>666,426</small>
|<small>370,218</small>
|<small>659,647</small>
|<small>658,798</small>
|<small>678,085</small>
!6,394,136
|-
!2017
|<small>678,210</small>
|<small>587,017</small>
|<small>675,612</small>
|<small>654,031</small>
|<small>672,376</small>
|<small>609,098</small>
|<small>669,451</small>
|<small>670,979</small>
|<small>650,244</small>
|<small>674,261</small>
|<small>656,854</small>
|<small>677,280</small>
!7,875,413
|-
!2018
|<small>677,499</small>
|<small>587,101</small>
|<small>110,504</small>
|<small>658,777</small>
|<small>677,003</small>
|<small>652,759</small>
|<small>672,925</small>
|<small>671,524</small>
|<small>651,877</small>
|<small>678,299</small>
|<small>660,812</small>
|<small>681,191</small>
!7,380,271
|-
!2019
|<small>618,699</small>
|<small>615,242</small>
|<small>680,076</small>
|<small>657,639</small>
|<small>677,666</small>
|<small>653,008</small>
|<small>671,001</small>
|<small>673,169</small>
|<small>572,934</small>
|<small>677,455</small>
|<small>659,759</small>
|<small>680,811</small>
!7,837,459
|-
!2020
|<small>662,767</small>
|<small>497,614</small>
|<small>80,585</small>
|<small>644,305</small>
|<small>677,539</small>
|<small>650,290</small>
|<small>669,007</small>
|<small>671,791</small>
|<small>653,716</small>
|<small>679,261</small>
|<small>660,108</small>
|<small>681,080</small>
!7,228,063
|-
!2021
|<small>682,989</small>
|<small>617,369</small>
|<small>679,866</small>
|<small>655,488</small>
|<small>672,213</small>
|<small>650,332</small>
|<small>585,691</small>
|<small>650,390</small>
|<small>651,170</small>
|<small>665,185</small>
|<small>658,172</small>
|<small>610,276</small>
!7,779,141
|-
!2022
|<small>680,675</small>
|<small>505,835</small>
|<small>64,192</small>
|<small>237,329</small>
|<small>659,465</small>
|<small>651,990</small>
|<small>671,667</small>
|<small>670,635</small>
|<small>652,660</small>
|<small>678,774</small>
|<small>659,119</small>
|<small>359,992</small>
!6,492,333
|-
!2023
|<small>681,308</small>
|<small>616,035</small>
|<small>682,419</small>
|<small>658,746</small>
|<small>678,165</small>
|<small>652,624</small>
|<small>672,339</small>
|<small>672,860</small>
|<small>653,155</small>
|<small>678,292</small>
|<small>659,495</small>
|<small>680,290</small>
!7,985,728
|-
!2024
|<small>680,082</small>
|<small>636,547</small>
|<small>73,343</small>
|<small>651,301</small>
|<small>674,438</small>
|<small>649,154</small>
|<small>669,754</small>
|<small>670,168</small>
|<small>650,562</small>
|<small>675,560</small>
|<small>657,241</small>
|<small>679,973</small>
!7,368,123
|-
!2025
|<small>679,610</small>
|<small>613,535</small>
|<small>676,274</small>
|<small></small>
|<small></small>
|<small></small>
|<small></small>
|<small></small>
|<small></small>
|<small></small>
|<small></small>
|<small></small>
!--
|-
|}

== Incident history ==
=== 1977 first stuck-open pilot-operated relief valve ===
On September 24, 1977, the [[pilot-operated relief valve|relief valve]] for the reactor pressurizer failed to close when the reactor, running at only 9% power, shut down because of a disruption in the feedwater system.<ref>Walker, Samuel J. (2004) ''Three Mile Island: A Nuclear Crisis in Historical Perspective''. Berkeley: [[University of California Press]]. p 68.</ref>

This incident later became a precursor to the [[Three Mile Island accident]], in which a pilot-operated relief valve also became stuck open, leaking thousands of gallons of coolant water into the basement of the reactor building.<ref>{{Cite web |last=Behr |first=Peter |last2=Greenwire |title=Three Mile Island still haunts U.S. nuclear industry - NYTimes.com |url=https://archive.nytimes.com/www.nytimes.com/gwire/2009/03/27/27greenwire-three-mile-island-still-haunts-us-reactor-indu-10327.html?pagewanted=all |access-date=April 24, 2023 |website=archive.nytimes.com}}</ref>

=== 1985 loss of feedwater event ===
On June 9, 1985, the main [[Boiler feedwater pump|feedwater pumps]], used to supply water to the reactor steam generators, shut down.  A control room operator then attempted to start the auxiliary (emergency) feedwater pumps.  These pumps both tripped on overspeed conditions because of operator error.  This incident was originally classified an "[https://www.nrc.gov/about-nrc/emerg-preparedness/about-emerg-preparedness/emerg-classification.html NRC Unusual Event]" (the lowest [[Nuclear safety in the United States#Emergency Classifications|classification]] the NRC uses) but it was later determined that it should have been classified a "site area emergency".<ref>{{cite web | author=Nuclear Regulatory Commission | title=Information Notice 85-80 | url=https://www.nrc.gov/reading-rm/doc-collections/gen-comm/info-notices/1985/in85080.html |access-date=June 14, 2006| author-link=Nuclear Regulatory Commission }}</ref>

=== 1998 tornado ===
On June 24, 1998, the station was struck by an [[Fujita scale|F2]] tornado.<ref>{{cite web | author=United States Senate | title=U.S. Senate Committee on Environment & Public Works Hearing Statements | url=http://epw.senate.gov/hearing_statements.cfm?id=248112 | access-date=July 7, 2006 | archive-url=https://web.archive.org/web/20060630050955/http://epw.senate.gov/hearing_statements.cfm?id=248112 | archive-date=June 30, 2006 | url-status=dead | author-link=United States Senate }}</ref> The plant's switchyard was damaged and access to external power was disabled. The plant's reactor automatically shut down at 8:42&nbsp;pm and an alert (the next to lowest of four levels of severity) was declared at 9:18&nbsp;pm. The plant's emergency diesel generators powered critical facility safety systems until external power could be restored.<ref>{{cite web | author=Nuclear Regulatory Commission | title=News Release III-98-040 | url=http://permanent.access.gpo.gov/lps11598/www.nrc.gov/reading-rm/doc-collections/news/1998/98-40iii.html | access-date=July 7, 2006| author-link=Nuclear Regulatory Commission }}</ref><ref>{{cite web | author=Nuclear Regulatory Commission | title=News Announcement RIII-98-40a | url=http://permanent.access.gpo.gov/lps11598/www.nrc.gov/reading-rm/doc-collections/news/1998/98-40aiii.html |  access-date=June 14, 2006| author-link=Nuclear Regulatory Commission }}</ref>

=== 2002 reactor head hole ===
[[File:Davis-BesseHole.png|thumb|Erosion of the {{convert|6|in|mm|adj=mid|-thick}} [[carbon steel]] reactor head, caused by a persistent leak of borated water]]
In March 2002, plant staff discovered that the [[boron|borated]] water that serves as the reactor coolant had leaked from cracked control rod drive mechanisms directly above the reactor and eaten through more than six inches<ref>[https://www.nrc.gov/reading-rm/doc-collections/nuregs/brochures/br0353/br0353r1.pdf NRC NUREG/BR-0353, Rev 1, pg 4]</ref> (150&nbsp;mm) of the carbon steel reactor pressure vessel head over an area roughly the size of a football (see photo).  This significant reactor head wastage on the exterior of the reactor vessel head left only {{convert|3/8|in|mm}} of stainless steel cladding holding back the high-pressure (~2155&nbsp;psi, 14.6&nbsp;[[Pascal (unit)|MPa]]) reactor coolant.  A breach most likely would have resulted in a massive [[loss-of-coolant accident]]{{citation needed|date=December 2018}}, in which reactor coolant would have jetted into the reactor's [[containment building]] and resulted in emergency safety procedures to protect from core damage or meltdown.  Because of the location of the reactor head damage, such a jet of reactor coolant might have damaged adjacent control rod drive mechanisms, hampering or preventing reactor shut-down.  As part of the system reviews following the accident, significant safety issues were identified with other critical plant components, including the following:
# the containment sump that allows the reactor coolant to be reclaimed and reinjected into the reactor;
# the high pressure injection pumps that would reinject such reclaimed reactor coolant;
# the emergency diesel generator system;
# the containment air coolers that would remove heat from the containment building;
# reactor coolant isolation valves; and
# the plant's electrical distribution system.<ref>Cleveland Plain Dealer, Problems and solutions, July 16, 2003</ref>

The resulting corrective operational and system reviews and engineering changes took two years.  Repairs and upgrades cost $600&nbsp;million, and the Davis–Besse reactor was restarted in March&nbsp;2004.<ref>NRC. [https://www.nrc.gov/reading-rm/doc-collections/enforcement/actions/reactors/ea05071.html EA-05-071 – Davis–Besse]. April 21, 2005.</ref> To replace the reactor vessel head, FirstEnergy purchased one from the mothballed [[Midland Nuclear Power Plant]] in [[Midland, Michigan]].<ref>{{cite web|url=https://www.nrc.gov/reactors/operating/ops-experience/vessel-head-degradation/vessel-head-degradation-files/06-04-02-mtg-sum.pdf|title=DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 - MEETING SUMMARYOF JUNE 4, 2002, TO DISCUSS THE REACTOR PRESSURE VESSELCLOSURE HEAD REPLACEMENT|publisher=Nuclear Regulatory Commission (NRC)|date=July 2, 2002|access-date=August 6, 2019}}</ref>

The NRC determined that this incident was the fifth-most dangerous nuclear incident in the United States since 1979,<ref name="nrc.gov"/> and imposed its largest fine ever—more than $5&nbsp;million—against FirstEnergy for the actions that led to the corrosion.<ref name=nrc2009>{{cite web |url=https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/fs-davis-besse-improv.html |title=Fact Sheet on Improvements Resulting From Davis–Besse Incident |author=NRC |date=September 2009 |work=NRC Fact Sheet }}</ref>

==== Criminal prosecutions ====
In January 2006, First Energy, the owner of Davis–Besse, acknowledged a series of safety violations by former workers, and entered into a [[deferred prosecution agreement]] with the [[United States Department of Justice]] (DOJ).  The deferred prosecution agreement related to the March 2002 incident.  The deferment granted by the NRC were based on letters from Davis–Besse engineers stating that previous inspections were adequate. However, those inspections were not as thorough as the company suggested, as proved by the material deficiency discovered later.  In any case, because FirstEnergy cooperated with investigators on the matter, they were able to avoid more serious penalties. The company paid $28&nbsp;million under a settlement with the Justice Department.<ref name=nrc2009 />  $23.7&nbsp;million of that were fines, with an additional $4.3&nbsp;million to be contributed to various groups, including the [[National Park Service]], the U.S. [[US Fish and Wildlife Service|Fish and Wildlife Service]], [[Habitat for Humanity]], and the [[University of Toledo]] as well as to pay some costs related to the federal investigation.<ref name=28mill/>

Two former employees and one former contractor were indicted for statements made in multiple documents and one videotape, over several years, for hiding evidence that the reactor pressure vessel was being corroded by [[boric acid]].  The maximum penalty for the three was 25 years in prison.  The indictment mentions that other employees also provided false information to inspectors, but does not name them.<ref name=28mill>{{cite web | author=United States Department of Justice | date=January 20, 2006 | title=Firstenergy Nuclear Operating Company to Pay $28 Million Relating to Operation of Davis–Besse Nuclear Power Station | url=http://www.usdoj.gov/opa/pr/2006/January/06_enrd_029.html | access-date=June 14, 2006 }} and {{cite web | date=January 20, 2006| title=Deferred prosecution agreement between the United States of America and FirstEnergy Nuclear Operating Company | url=http://www.corporatecrimereporter.com/documents/fenco_000.pdf | access-date=June 14, 2006 | archive-url=https://web.archive.org/web/20070927222718/http://www.corporatecrimereporter.com/documents/fenco_000.pdf | archive-date=September 27, 2007 | url-status=dead }}</ref><ref>[http://www.toledoblade.com/apps/pbcs.dll/article?AID=/20080827/NEWS02/808270429 Toledo Blade "Ex-engineer found guilty of concealing Davis–Besse dangers"]</ref> In 2007, one of these men was convicted and another acquitted of hiding information from and lying to the NRC. Another jury trial in 2008 convicted the remaining engineer of similar crimes.<ref>{{cite web | date=August 26, 2008 | title=Former FENOC Employee Convicted for Concealing Information from the Nuclear Regulatory Commission | url=https://www.justice.gov/archive/opa/pr/2008/August/08-enrd-752.html | access-date=February 23, 2021}}</ref>

=== 2003 slammer worm computer virus ===
In January 2003, the plant's private network became infected with the [[SQL Slammer|slammer worm]], which resulted in a five-hour loss of safety monitoring at the plant.<ref>[[The Register]] [https://www.theregister.co.uk/2003/08/20/slammer_worm_crashed_ohio_nuke/] August 20, 2003</ref><ref>Security Focus [http://www.securityfocus.com/news/6767] August 19, 2003</ref>

=== 2008 discovery of tritium leak ===
The NRC and [[Ohio Environmental Protection Agency]] (Ohio EPA) were notified of a [[tritium]] leak accidentally discovered during an unrelated fire inspection on October 22, 2008.  Preliminary indications suggest radioactive water did not infiltrate groundwater outside plant boundaries.<ref>{{cite news|url=http://www.toledoblade.com/apps/pbcs.dll/article?AID=/20081025/NEWS16/810250355|title=Davis–Besse radioactive leak is fixed|newspaper=The Blade|date=October 25, 2008}}</ref>

=== 2010 replacement reactor head problems ===
During a scheduled refueling outage in 2010, ultrasonic examinations performed on the [[control rod]] drive mechanism nozzles penetrating the reactor vessel closure head identified that two of the nozzles inspected did not meet acceptance criteria. FirstEnergy investigators subsequently found new cracks in 24 of 69 nozzles, including one serious enough to leak boric acid.<ref>{{cite news
| author       =<!--Staff writer(s); no by-line.-->
| title        = 8 more nozzles at Davis-Besse found to be flawed
| url          = http://www.toledoblade.com/local/2010/05/04/8-more-nozzles-at-Davis-Besse-found-to-be-flawed.html
| newspaper    = [[The Blade (Toledo)|The Blade]]
| location     = Toledo, OH
| date         = May 4, 2010
| access-date  = July 27, 2015
}}</ref><ref>{{cite news
| author       =<!--Staff writer(s); no by-line.-->
| title        = Meeting set to discuss Besse reactor-head flaws
| url          = http://www.toledoblade.com/local/2010/05/15/Meeting-set-to-discuss-Besse-reactor-head-flaws.html
| newspaper    = [[The Blade (Toledo)|The Blade]]
| location     = Toledo, OH
| date         = May 15, 2010
| access-date  = July 27, 2015
}}</ref>  Crack indications required repair prior to returning the vessel head to service. Control rod drive nozzles were repaired using techniques proven at other nuclear facilities. The plant resumed operation in 2010. The existing reactor vessel head was scheduled for replacement in 2011.<ref>{{cite news
| last         = Funk
| first        = John
| date         = June 21, 2010
| title        = FirstEnergy to replace lid on Davis-Besse nuclear power plant
| url          = http://www.cleveland.com/business/index.ssf/2010/06/firstenergy_to_place_lid_on_da.html
| newspaper    = [[The Plain Dealer]]
| location     = Cleveland, OH
| access-date  = July 27, 2015
}}</ref>

=== 2011 shield building cracks ===
An October 2011 shutdown of the plant for maintenance revealed a 30 foot long hairline crack in the concrete shield building around the containment vessel.<ref>{{Citation | url = http://www.toledoblade.com/local/2012/01/06/David-Besse-s-restart-proper-company-NRC-officials-say.html | newspaper = Toledo Blade | date = January 6, 2012 | title = Davis–Besse's restart proper, company, NRC officials say | access-date = January 14, 2012 }}</ref>

=== 2012 reactor coolant pump seal pinhole leak ===
On June 6, 2012, an approximately 0.1&nbsp;[[gallons per minute|gpm]] pinhole spray leakage was identified from a weld in a seal of the reactor coolant pump during a routine reactor coolant system walkdown inspection.  The plant entered limited operations, and root cause analysis was undertaken.<ref>{{Citation | url = https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2012/20120607en.html#en48000 | title = NRC Event Report 48000 | access-date = June 8, 2012 }}</ref>

=== 2015 steam leak shutdown ===
On May 9, 2015, a steam leak in the turbine building caused FirstEnergy operators to declare an [[Nuclear safety in the United States#Emergency Classifications|'Unusual Event']] and shut the reactor down until repairs could be made.<ref>{{cite news|title=Davis-Besse still shutdown due to steam issue|url=http://www.sanduskyregister.com/news/science/8086641|newspaper=Sandusky Register|access-date = May 12, 2015}}</ref>  The plant was brought back online and synchronized with the local power grid at May 12 after repairs were completed.<ref>{{cite news|title=Davis-Besse expected to be at full power today|url=http://www.toledoblade.com/local/2015/05/14/Davis-Besse-expected-to-be-at-full-power-today.html|last=Henry|first=Tom|newspaper=The Blade|date=May 14, 2015|access-date=May 18, 2015}}</ref>

== Future ==
{{further|Ohio nuclear bribery scandal}}

The facility's original nuclear operating license was set to expire on April 22, 2017. In August 2006, FirstEnergy Nuclear Operating Company (FENOC) submitted a letter of intent to renew.<ref>{{cite web|url=http://adamswebsearch2.nrc.gov/idmws/doccontent.dll?library=PU_ADAMS^PBNTAD01&ID=062370089|title=FENOC letter of intent for license renewal|archive-url= https://web.archive.org/web/20071017211028/http://adamswebsearch2.nrc.gov/idmws/doccontent.dll?library=PU_ADAMS%5EPBNTAD01&ID=062370089 |date=August 11, 2006|archive-date=October 17, 2007}}</ref> The submission date for the application was August 10, 2010. On December 8, 2015, the NRC granted a 20-year license extension to expire on April 22, 2037.<ref>{{Cite web|url= https://www.nrc.gov/docs/ML0531/ML053110490.pdf |title=FIRSTENERGY NUCLEAR OPERATING COMPANY AND FIRSTENERGY NUCLEAR GENERATION, LLC DOCKET NO. 50-346 DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1 RENEWED FACILITY OPERATING LICENSE|publisher=Nuclear Regulatory Commission}}</ref> On March 31, 2018, FirstEnergy Nuclear Operating Company filed for Bankruptcy protection.<ref>{{Cite web|url=https://www.fes.com/content/fes/home/restructuring.html|title=FirstEnergy Solutions - Restructuring|publisher=FirstEnergy Solutions Corp|access-date=May 10, 2019|archive-date=May 10, 2019|archive-url=https://web.archive.org/web/20190510232510/https://www.fes.com/content/fes/home/restructuring.html|url-status=dead}}</ref> Around that time, the company indicated it would close the nuclear plant.<ref>{{Cite web|url= https://neutronbytes.com/2018/04/01/first-energy-files-for-bankruptcy-to-close-4-nuclear-reactors |title=First Energy Files for Bankruptcy; To Close 4 Nuclear Reactors|date=April 1, 2018|publisher=Neutron Bytes|access-date=May 10, 2019}}</ref> In 2019, Ohio lawmakers debated a $9/MWh subsidy to keep Davis–Besse open.<ref>{{cite web |last1=Pelzer |first1=Jeremy |title=How (un)profitable are Ohio's two nuclear plants? FirstEnergy Solutions says it can't tell the public |url=https://www.cleveland.com/open/2019/06/how-unprofitable-are-ohios-two-nuclear-plants-firstenergy-solutions-says-it-cant-tell-the-public.html |website=cleveland.com |date=June 24, 2019}}</ref> House Bill 6 was signed into law on July 23, 2019, and FirstEnergy announced it would refuel Davis–Besse and rescind its deactivation notice on July 24, 2019.<ref name=rescind /> It was later learned that the bill itself was a part of a public corruption scheme revealed by the Justice Department in July 2020.<ref>{{cite court|url=https://assets.documentcloud.org/documents/6999130/Ohio-House-complaint.pdf|litigants=U.S. v. Larry Householder, Jeffery Longstreth, Neil Clark, Matthew Borges, Juan Cespedes, and Generation Now|court=S.D. Ohio|date=July 16, 2020|access-date=August 2, 2020}}</ref>

The scheme involved FirstEnergy paying approximately $61 million to the Speaker of the Ohio House of Representatives, Larry Householder, and Matt Borges, Neil Clark, Juan Cespedes and Jeff Longstreth.  For this, they were supposed to help pass the bill subsidizing the nuclear plant and prevent its repeal.  Householder was found guilty, removed from the Ohio House and sentenced to 20 years in prison.  Clark committed suicide <ref>https://www.ans.org/news/article-6298/firstenergy-agrees-to-20-million-settlement-in-ohio-bribery-case/</ref>

==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 Davis–Besse was 1 in 149,254, according to an NRC study published in August 2010.<ref>[[Bill Dedman]], "What are the odds? US nuke plants ranked by quake risk," ''[[msnbc.com]]'', March 17, 2011 [https://web.archive.org/web/20110317103441/http://www.msnbc.msn.com/id/42103936/] Accessed April 19, 2011.</ref><ref>{{Cite web |url=http://msnbcmedia.msn.com/i/msnbc/Sections/NEWS/quake%20nrc%20risk%20estimates.pdf |title=Archived copy |access-date=May 5, 2017 |archive-url=https://web.archive.org/web/20170525170632/http://msnbcmedia.msn.com/i/msnbc/Sections/NEWS/quake%20nrc%20risk%20estimates.pdf |archive-date=May 25, 2017 |url-status=dead }}</ref>

== Surrounding population ==

The [[Nuclear Regulatory Commission]] defines two emergency planning zones around nuclear power plants: a plume exposure pathway zone with a radius of {{convert|10|mi}}, concerned primarily with exposure to, and inhalation of, airborne radioactive contamination, and an ingestion pathway zone of about {{convert|50|mi}}, concerned primarily with ingestion of food and liquid contaminated by radioactivity.<ref>{{cite web|url=https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/emerg-plan-prep-nuc-power-bg.html |title=NRC: Backgrounder on Emergency Preparedness for Nuclear Power Plants |access-date=December 13, 2013 |url-status=dead |archive-url=https://web.archive.org/web/20061002131207/http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/emerg-plan-prep-nuc-power-bg.html |archive-date=October 2, 2006 }}</ref>

The 2010 U.S. population within {{convert|10|mi}} of Davis–Besse was 18,635, an increase of 14.2 percent in a decade, according to an analysis of U.S. Census data for [[msnbc.com]]. The 2010 U.S. population within {{convert|50|mi}} was 1,791,856, an increase of 1.4 percent since 2000. Cities within {{convert|50|mi}} include [[Sandusky, Ohio]], {{convert|22|mi}}; [[Toledo, Ohio]] {{convert|26|mi}}; and [[Detroit|Detroit, Michigan]], {{convert|50|mi}} (distance to the city centers).<ref>[[Bill Dedman]], Nuclear neighbors: Population rises near US reactors, ''[[msnbc.com]]'', April 14, 2011 [https://web.archive.org/web/20110415234014/http://www.msnbc.msn.com/id/42555888/ns/us_news-life/] Accessed May 1, 2011.</ref>
U.S. Census data for Canadian population within the area is not available, though [[Leamington, Ontario]] (population: 30,000) is {{convert|39|mi}} away, and [[Windsor, Ontario]] (population: 241,000) is {{convert|49|mi}} from Davis–Besse.

The cooling tower for Davis–Besse stands at 493 feet above the surrounding area, making it a major landmark around the western end of Lake Erie. The tower is visible from the Michigan and Ontario shores and on clear days the condensing steam plume can be seen from [[Bowling Green, Ohio]], over 40 miles away{{citation needed|date=September 2014}}.<!--I'm looking for a citation for this, but I've seen it with my own eyes. Apparently aviation students at BGSU like to use the plume for navigation.-->

==See also==
{{stack|{{Portal|Ohio|Energy|Nuclear technology}}}}
* [[Nuclear reactor accidents in the United States]]
* [[Pilot-operated relief valve]]

==References==
{{Reflist|colwidth=30em}}

==External links==
* [https://www.nrc.gov/info-finder/reactor/davi.html Davis–Besse Pressurized Water Reactor Information] from the U.S. [[Nuclear Regulatory Commission]]
* [http://www.ucsusa.org/clean_energy/nuclear_safety/overview_db.html Union of Concerned Scientists report on Davis–Besse]
* [https://www.nrc.gov/reactors/operating/ops-experience/vessel-head-degradation/lessons-learned.html U.S. Nuclear Regulatory Commission's "Davis–Besse Lessons Learned Task Force" (with links to the Task Force Report)]

{{U.S. Nuclear Plants}}

{{DEFAULTSORT:Davis-Besse Nuclear Power Station}}
[[Category:Energy infrastructure completed in 1978]]
[[Category:Towers completed in 1978]]
[[Category:Civilian nuclear power accidents]]
[[Category:Disasters in Ohio]]
[[Category:Nuclear power plants in Ohio]]
[[Category:Buildings and structures in Ottawa County, Ohio]]
[[Category:Towers in Ohio]]
[[Category:Nuclear power stations using pressurized water reactors]]
[[Category:FirstEnergy]]
[[Category:Nuclear accidents and incidents in the United States]]
[[Category:Non-renewable resource companies established in 1978]]