- Nuclear decommissioning
-
Nuclear decommissioning is the dismantling of a nuclear power plant and decontamination of the site to a state no longer requiring protection from radiation for the general public. The main difference from the dismantling of other power plants is the presence of radioactive material that requires special precautions.
Generally speaking, nuclear plants were designed for a life of about 30 years. Newer plants are designed for a 40 to 60-year operating life.
Decommissioning involves many administrative and technical actions. It includes all clean-up of radioactivity and progressive demolition of the plant. Once a facility is decommissioned, there should no longer be any danger of a radioactive accident or to any persons visiting it. After a facility has been completely decommissioned it is released from regulatory control, and the licensee of the plant no longer has responsibility for its nuclear safety.
Contents
Decommissioning options
The International Atomic Energy Agency has defined three options for decommissioning, the definitions of which have been internationally adopted:
- Immediate Dismantling (or Early Site Release/Decon in the US): This option allows for the facility to be removed from regulatory control relatively soon after shutdown or termination of regulated activities. Usually, the final dismantling or decontamination activities begin within a few months or years, depending on the facility. Following removal from regulatory control, the site is then available for re-use.
- Safe Enclosure (or Safestor(e) SAFSTOR): This option postpones the final removal of controls for a longer period, usually in the order of 40 to 60 years. The facility is placed into a safe storage configuration until the eventual dismantling and decontamination activities occur.
- Entombment: This option entails placing the facility into a condition that will allow the remaining on-site radioactive material to remain on-site without the requirement of ever removing it totally. This option usually involves reducing the size of the area where the radioactive material is located and then encasing the facility in a long-lived structure such as concrete, that will last for a period of time to ensure the remaining radioactivity is no longer of concern.
Experience
See also: List of nuclear reactorsA wide range of nuclear facilities has been decommissioned so far. This includes nuclear power plants (NPPs), research reactors, isotope production plants, particle accelerators, and uranium mines. The number of decommissioned power plants is small. There are companies specialized in nuclear decommissioning; the practice of decommissioning has turned into a profitable business. Decommissionning is very expensive. The current estimate by the United Kingdom's Nuclear Decommissioning Authority is that it will cost at least £70 billion to decommission the 19 existing United Kingdom nuclear sites; this takes no account of what will happen in the future. Also, due to the radioactivity in the reactor structure, decommissioning is a slow process which takes place in stages. The plans of the Nuclear Decommissioning Authority for decommissioning reactors have an average 50 year time frame. The long time frame makes reliable cost estimates extremely difficult. Excessive cost overruns are not uncommon even for projects done in a much shorter time frame.
North America
Several nuclear reactors dismantled in America, type, power and decommissioning cost (often is mentioned only the probable cost per kilowatt of power:[1][2][3]
Country: Location: Reactor type: Operative life: Decommissioning
phase:Dismantling
costs:Canada (Québec) Gentilly-1 CANDU-BWR
250 MWe180 days
(between 1966 and 1973)"Static state" since 1986[4][5][6] stage two:
US $ 25 MillionCanada
(Ontario)Pickering NGS
Units A2 and A3CANDU-PWR
8 x 542 MWe30 years
(from 1974 to 2004)Two units currently in "cold standby"
Decommissioning in 2012?(calculated:
$ 270–430/kWe ?)[citation needed]USA Fort St. Vrain HTGR
(helium-graphite)
380 MWe12 years
(1977–1989)Immediate Decon $ 195 Million USA Rancho Seco[7] Multiunit:
PWR
913 MWe12 years
(Closed after a referedum
nel 1989)SAFSTOR: 5–10 years
completion 2018?
($ 200–500/kWe)[8]USA Three Mile Island 2 Multiunit:
913 MWe PWRINCIDENT:
core fusion
(in 1979)Post-Defuelling
Phase 2 (1979)$ 805 Million
(estimated)[9]USA Shippingport (The first BWR)
60 MWe25 years
(closed in 1989)Decon completed
dismantled in 5 years
(first small
experimental reactor)$ 98.4 Million[10] USA Piqua(Ohio) OCM (Organically Cooled/Moderated) reactor
46 MWe[11]2 years
(closed in 1966)ENTOMB
(coolant design inadequate for neutron flux)unk USA Trojan PWR
1.180 MWe16 years
(Closed in 1993
because nearby to seismic fault)SAFSTOR:
(cooling tower
demolished in 2006)?[12][13] USA Yankee Rowe PWR 185 MWe 31 years
(1960–1991)DECON COMPLETED - Demolished
(greenfield open to visitors) [14]$608 million with $8 million per year upkeep USA Maine Yankee PWR
860 MWe24 years
(closed in 1996)DECON COMPLETED -
Demolished in 2004
(greenfield open to visitors) [15][16]$ 635 Million[17] USA Connecticut Yankee PWR
590 MWe28 years
(closed in 1996)Decon - demolished in 2007
(greenfield open to visitors) [18]$ 820 Million[19] USA Exelon -
Zion 1 & 2PWR - Westinghouse
2 x 1040 MWe25 years
(1973–1998)
(Incident in proceedings,
abandoned because
of the excessive cost of vaporizers substitution)SAFSTOR-EnergySolutions
(opening of the site to visitors for 2018) [20]$ 900–1,100 Million
(2007 dollars)[21]USA Pacific Gas & Electric -
Humboldt Bay Nuclear Power Plant - Unit 3BWR
1 x 63 MWe13 years
(1963–1976)
(Shut down due to seismic retrofit)On July 2, 1976, Humboldt Bay Power Plant (HBPP) Unit 3 was shut down for annual refueling and to conduct seismic modifications. In 1983, updated economic analyses indicated that restarting Unit 3 would probably not be cost-effective, and in June 1983, PG&E announced its intention to decommission the unit. On July 16, 1985, the U.S. Nuclear Regulatory Commission (NRC) issued Amendment No. 19 to the HBPP Unit 3 Operating License to change the status to possess-but-not-operate, and the plant was placed into a SAFSTOR status. Unknown - Closure date: 12/31/2015[22] Asia
Several nuclear reactors dismantled in Asia, type, power and decommissioning cost per kilowatt of electric power (source: World Nuclear Association article[23]).
Country: Location: Reactor type: Operative Life: Decommissioning
Phase:Dismantling
Cost:China[24] Beijing (CIAE) HWWR 10 MWe (multipurpose)
(Heavy Water Experimental Reactor for the production of plutonium and tritium)49 years
(1958–2007)Safestore & Decon in
20 years (until 2027)proposed:
$ 6 Million for dismantling
$ 5 Million for fuel remotionNorth Korea Yongbyon Magnox-type
(reactor for the production of nuclear weapons through PUREX treatment)20 years
(1985–2005)
Deactivated after a treaty[25][26]SAFESTORE:
Cooling tower dismantled? Japan Tokai-1 Magnox (GCR)
160 MWe32 years
(1966–1988)Safestore: 10 years[27][28]
then DECON
until 2018estimanted cost:
Yen 93 Billion[29]
(Euro 660 Million of 2003)India
[30],[31]Tarapur-1,2
(Maharashtra)2x BWR 160 MWe 40 years ?
(1969–2009?)NOT deactivated ? India[32] Rawatbhata Atomic Power Station-1,2
(Rajasthan)1x PHWR 100 MWe
1x PHWR 200 MWe
(similar to CANDU)40 years ?
(1970–2011?)NOT deactivated ? Iraq Osiraq/Tammuz-1
[33]BWR 40 MWe
Nuclear reactor with weapons-grade plutonium production capability(Destroyed by Israeli Air Force in 1981) Not radioactive:
Never refurbished with uranium? Western Europe
Several nuclear reactors dismantled in Western Europe, type, power and decommissioning cost per kilowatt of power: European Union Website about Nuclear Decommissioning,[34] World Nuclear Association (reactor building companies),[35] United Kingdom.[36]
Country: Location: Reactor type: Operative Life: Decommissioning
phase:Dismantling
cost:Austria[37]
(Nuclear Free Country)[38]Zwentendorf NPP
Google MapsPWR
723 MWeNever activated[39], after referendum in 1978 ? ? Belgium Mol PWR (BR-3) 25 years
(1962–1987)DECON COMPLETED -
pilot project
(underwater cutting and remote operated tools) [40][41]? France Brennilis HWGCR 70 MWe 12 years
(1967–1979)Phase 3 Euro 480 Million
(20 times the forecasted amount)France Bugey-1 UNGG
Gas cooled, graphite moderator1972-1994 postponed ? France Chinon 1,2,3 Gas-graphite
(1973–1990)postponed ? France Saint-Laurent Nuclear Power Plant Gas-graphite 1969-1992 postponed ? France Superphénix at
Creys-MalvilleFast breeder nuclear reactor
(sodium-cooled)11 years
(1985–1996)postponed estimated for the future:
$ 4000/kWe ?United Kingdom Berkeley Magnox
(2 x 138 MWe)27 years
(1962–1989)Safestore: 30 years
(internal demolition)$ 2600/kWe United Kingdom Sellafield-Windscale Windscale Advanced Gas Reactor
WAGR
(32 MWe)18 years
(1963–1981)Remotion of reactor in 2009 -
pilot project
(cutting with remote controlled robots, UV lasers) [40][42],[43][44]More than $2600/kWe
(WNI estimates)
So far € 117 MillionWest Germany Gundremmingen-A BWR
250 MWe
11 yearsImmediate
dismantling -
pilot project
(underwater cutting)(~ $ 300–550/kWe) Italy Caorso NPP BWR
840 MWe[45][46]3 years
( 1978 - Closed in 1987 after referendum in 1986 )Safstore: 30 years
(demolizione interna)euro 450 Million (dismantling)
+ 300 M fuel reprocessing[47][48][49][50]Italy Garigliano NPP (Caserta) BWR
150 MWe[51]? years
(Closed on March 1, 1982)Safstore: 30 years
(internal demolition)$/kWe Italy Latina NPP (Foce Verde) Magnox
210 MWe Gas-graphite[52]24 years
( 1962 - Closed in 1986 after referendum )Safstore: 30 years
(internal demolition)$/kWe Italy Trino Vercellese NPP PWR Westinghouse,
270 MWe[53]? years
( Closed in 1986 after referendum )Safstore: 30 years
(internal demolition)$/kWe Nederlands Dodewaard NPP BWR Westinghouse,
58 MWe[54]28 years
(1969–1997)Defuelling completed -
Safstore for 40 years$/kWe Slovenia
(former-Yugoslavia)Krsko NPP[55] PWR (Westinghouse)
696 MWe40? years
(1981–2021?)Will be deactivated in 2022 ? Spain Vandellós NPP-1 UNGG
480 MWe
(gas-graphite)18 years
Incident:
fire in a turbogenerator
(1989)Safestore: 30 years
(internal demolition)Phases 1 and 2:
Euro 93 MillionSwitzerland[56] DIORIT MWe Gas-graphite
(experimental)
()Safestore: ? years
(internal demolition)? Switzerland LUCENS 8,3 MWe CO2-heavy water
(experimental)(1962–1969)
Incident:
fire in 1969Entombment for ? years
Safestore & Decon: 24 years
(internal demolition)? Switzerland SAPHIR 0,01-0,1 MWe
(Light water pool)39 years
(1955–1994)
(Experimental demonstrator)(In public display
since inauguration
open to visitors:
"Cherenkov's light")? - Repository for radioactive waste Morsleben: 2.2 billion euro.
Eastern Europe and former Soviet Union
Several nuclear reactors dismantled in the nations born from the former Soviet Union: (Belarus, Russia, Ukraine and others) and rectors dismantled in countries formerly belonging to "Warsaw Pact" and/or to "Comecon", type, electric power and decommissioning cost per kilowatt of power: World Nuclear Association,[57] OSTI (Russia & USA).[3]
Country: Location: Reactor typr: Operative life: Decommissioning
phase:Dismantling
cost:Bulgaria Kozloduy NPP-1,2,3,4[58] PWR VVER-440
(4 x 408 MWe)Reactors 1,2 closed in 2003,
reactors 3,4 closed in 2006
(Closing forced
by European Union)De-fuelling ? East Germany Greifswald NPP-1,
2,3,4,5VVER-440
5 x 408 MWeImmediate
dismantling
(underwater cutting)(~ $ 330/kWe) East Germany Rheinsberg NPP-1 VVER-210
70–80 MWe24 years
(1966–1990)In dismantling
since 1996
Safstor (underwater cutting)(~ $ 330/kWe) East Germany Stendal NPP-1,2,3,4 VVER-1000
(4 x 1000 MWe)Never activated
(1st reactor 85% completed)NOT radioactive
(Cooling towers
demolished with explosives)(?)
(Structure in exhibition
inside an
industrial park)Russia Mayak[59]
(Chelyabinsk-65)PUREX plant for
uranium enrichmentSeveral severe incidents
(1946–1956)? ? Russia Seversk[60]
(Tomsk-7)Three plutonium reactors
Plant for uranium enrichmentTwo fast-breeder reactors closed (of three), after disarmaments agreements with USA in 2003[61]. ? ? Slovakia Mochovce NPP-1,2
(180 km east from Vienna)[62][63]VVER 440
2 X 440 MWe(1998–2028?) ? Ukraine Chernobyl NPP-4
(110 km
from Kiev)RBMK-1000
1000 MWe? years
WORST NUCLEAR ACCIDENT IN ALL HISTORY: hydrogen explosion, then graphite fire (1986)
See:Chernobyl disasterENTOMBMENT
(armed concrete "sarcophagus")Past: ?
Future: riding sarcophagus in steel[64]Legal aspects
The decommission of a nuclear reactor can only take place after the appropriate licence has been granted pursuant to the relevant legislation. As part of the licensing procedure various documents, reports and expert opinions have to be written and delivered to the competent authority, e.g. safety report, technical documents, environmental impact study (EIS).
In the European Union these documents are the basis for the environmental impact assessment (EIA) according to Council Directive 85/337/EEC. A precondition for granting such a licence is an opinion by the European Commission according to Article 37 of the Euratom Treaty. Article 37 obliges every Member State of the European Union to communicate certain data relating to the release of radioactive substances to the Commission. This information must reveal whether and if so what radiological impacts decommissioning – planned disposal and accidental release – will have on the environment, i.e. water, soil or airspace, of the EU Member States.[65] On the basis of these general data, the Commission must be in a position to assess the exposure of reference groups of the population in the nearest neighbouring states.
Cost of decommissioning
In USA many utilities estimates now average $325 million per reactor all-up (1998 $).
In France, decommissioning of Brennilis Nuclear Power Plant, a fairly small 70 MW power plant, already cost 480 million euros (20x the estimate costs) and is still pending after 20 years. Despite the huge investments in securing the dismantlement, radioactive elements such as Plutonium, Cesium-137 and Cobalt-60 leaked out into the surrounding lake.[66][67]
In the UK, decommissioning of the Windscale Advanced Gas Cooled Reactor (WAGR), a 32 MW prototype power plant, cost 117 million euros.
In Germany, decommissioning of Niederaichbach nuclear power plant, a 100 MW power plant, amounted to more than 143 million euros.
Decommissioning funds
In Europe there is considerable concern on the funds necessary to finance final decommissioning. In many countries either the funds do not appear sufficient to pay the financial decommissioning, and in other countries the funds are being used for activities other than decommissioning, putting the funds at risk, and distorting competition with parties who do not have nuclear decommissioning funds available.[68]
Currently (2008) the European Commission is looking into this issue.
Similar concerns exist in the United States, where the U.S. Nuclear Regulatory Commission has located apparent decommissioning funding assurance shortfalls and requested 18 nuclear power plants to address that issue.[69]
International collaboration
Organizations that promote the international sharing of information, knowledge, and experiences related to nuclear decommissioning include the International Atomic Energy Agency, the Organization for Economic Co-operation and Development's Nuclear Energy Agency and the European Atomic Energy Community [70]. In addition, an online system called the Deactivation and Decommissioning Knowledge Management Information Tool was developed under the United States Department of Energy and made available to the international community to support the exchange of ideas and information. The goals of international collaboration in nuclear decommissioning are to reduce decommissioning costs and improve worker safety [71].
Ships, mobile reactors, military reactors
Many warships, and a few civil ships, have used nuclear reactors for propulsion. Former Soviet and American warships have been taken out of service and their power plants removed or scuttled. Dismantling of Russian submarines and ships and American submarines and ships is ongoing. Marine power plants are generally smaller than land-based electrical generating stations.
See also
- Nuclear Decommissioning Authority
- Ship-Submarine recycling program
- Nuclear entombment
- Marcoule (French nuclear site)
- D&D KM-IT (Deactivation and Decommissioning Knowledge Management Information Tool)
References
- ^ Nuclear Decommissioning article by World Nuclear Association (associaciation of nuclear reactors builders: [1]
- ^ NRC: Locations of Power Reactor Sites Undergoing Decommissioning
- ^ a b OSTI: Appendix A - A Summary of the Shutdown and Decommissioning Experience for Nuclear Power Plants in the United States and the Russian Federation. Appendix B - A Summary of the Regulatory Environment for the Shutdown and Decommissioning of Nuclear Power Plants in the United States and the Russian Federation. Appendix C - Recommended Outlines for Decommissioning Documentation
- ^ IAEA: Taking Canada's Gentilly-1 to a "static state (by Balarko Gupta)
- ^ ASCE: Gentilly-1 a study in nuclear decommission
- ^ A Chernobyl in Québec? (correspondence on the dangers of Québec's only nuclear plant)
- ^ OSTI: Energy Citations Database about Rancho Seco nuclear power plant
- ^ US-NRC: Rancho Seco nuclear power plant
- ^ UNITED STATES NUCLEAR REGULATORY COMMISSION: Three Mile Island - Decommissioning Unit 2
- ^ OSTI, Office of Scientific and Technical Information - Shippingport station decommissioning project: start of physical decommissioning
- ^ US NRC Information Digest 2008-2009
- ^ Koberstein, Paul (2005-03-09). "Trojan: PGE's Nuclear Gamble". Willamette Week: p. A1. http://www.wweek.com/editorial/3118/6073/. Retrieved 2007-06-15.
- ^ "Trojan Nuclear Plant Decommissioning Update" (PDF). Issues in Perspective. Portland General Electric. March 2006. http://www.portlandgeneral.com/about_PGE/corporate_info/trojan/images/issues_in_perspective.pdf. Retrieved 2008-04-06.[dead link]
- ^ Yankee Rowe Nuclear Reactor (third nuclear reactor in USA, totally dismantled)
- ^ Maine Yankee Nuclear Power Station, ME - Power Technology
- ^ Maine Yankee Decommissioning 80% Complete
- ^ Maine Yankee Decommissioning Experience Report
- ^ Connecticut Yankee Nuclear Reactor - Complete Decommissioning
- ^ SEC-INFORMATION: Connecticut Yankee The United Illuminating Company (UI), a wholly owned subsidiary of UIL Holdings Corporation (UIL), owns 9.5% of the equity of Connecticut Yankee Atomic Power Company. Connecticut Yankee has prepared a draft updated estimate of the cost of decommissioning its nuclear unit, as part of its transition to self performance of decommissioning. Connecticut Yankee's draft updated cost estimate includes an increase of approximately $270 million over the cost estimate reported in November 2002
- ^ With Exelon's Zion 1 & 2 reactors (2 x 1098 MWe) closed down in 1998 and in Safstor, a slightly different process is envisaged, considerably accelerating the decommissioning. Exelon has contracted with a specialist company - EnergySolutions, to remove the plant and return the site to greenfield status. To achieve this, the plant's licence and decommissioning funds will be transferred to EnergySolutions, which will then be owner and licensee, and the site will be returned to Exelon about 2018. Used fuel would remain on site until taken to the national repository.
- ^ WEBWIRE: Exelon Nuclear To Accelerate Decommissioning Of Zion Station
- ^ http://www.nrc.gov/info-finder/decommissioning/power-reactor/humboldt-bay-nuclear-power-plant-unit-3.html
- ^ Nuclear Decommissioning article by the association of nuclear reactor builders http://www.world-nuclear.org
- ^ IAEA: Decommissioning in China
- ^ PRESS TV (Iranian News Agency): North Korea to decommission nuclear facility
- ^ THE GUARDIAN: Nuclear agreement: North Korea halts decommissioning
- ^ Article in IAEA-TECDOC--1043: Permanent cessation of Tokai power plant's operation
- ^ Science Links Japan: Progression of decommissioning of Tokai power plant. First case of power reactor in Japan.
- ^ Organisation for Economic Co-operation and Development/Nuclear Energy Agency, report 2003: "Strategy Selection for the Decommissioning of Nuclear Facilities" (page 118)
- ^ SCIDEV: India's energy mix needs nuclear boost
- ^ ECOWORLD: Nuclear power in India, by Avilash Roul
- ^ INDIA - CISED: Economics of Nuclear Power Heavy Water Reactors
- ^ Federation of American Scientists: Osiraq/Tammuz Nuclear Reactor
- ^ European webside on Decommissioning of Nuclear Intallations - Decommissioning in Europe
- ^ Nuclear Decommissioning (Reactor Building Companies) http://www.world-nuclear.org
- ^ British Parliament: Estimated dates for the dismantling of nuclear reactors in the United Kingdom
- ^ NEA: Decommissioning in Austria
- ^ EURONUCLEAR-NEWS: Can Austria Survive Without Nuclear Power ?
- ^ SUSTAINABILITY INSTITUTE: Zwentendorf, a Nuclear Plant That Will Never Be Turned On
- ^ a b EU-DECOM-belgium - From 1979 until now: five framework programmes
- ^ The European Nuclear Decommissioning Training Facility - Mol, Belgium, 2002
- ^ UKAEA - Case Studies - Decommissioning - Windscale Advanced Gas-Cooled Reactor[dead link]
- ^ DIXON, C (1999). "WAGR decommissioning : preparation, removal and disposal of the WAGR heat exchangers". Nuclear energy 38 (6): 361–369.
- ^ Summary of Responses to Discussion Letter on Future of Windscale
- ^ Zona Nucleare - La centrale nucleare in fase di smantellamento ex-ENEL di Caorso (Piacenza)
- ^ Il Fiume Po: La Centrale Nucleare di Caorso
- ^ Relazione della SOGIN per lo smantellamento di Caorso - ultima pagina
- ^ Via libera allo smantellamento della centrale di Caorso
- ^ Accordo tra la SOGIN e la Sudsvik svedese
- ^ LA REPUBBLICA: Per Caorso un addio lungo mezzo secolo, piano ENEL per smantellare la centrale
- ^ Zona Nucleare - La centrale nucleare in fase di smantellamento ex-ENEL di Garigliano (Caserta)
- ^ Zona Nucleare - La centrale nucleare in fase di smantellamento ex-ENEL di Foce Verde (Latina)
- ^ Zona Nucleare - La centrale nucleare in fase di smantellamento ex-ENEL di Trino Vercellese (Vercelli)
- ^ NEA: Decommissioning in the Netherlands ()
- ^ Nuclear Power in Slovenia
- ^ Nuclear Energy Agency: Decommissioning in Switzerland
- ^ Nuclear Decommissioning article by the international association of nuclear reactor builders http://www.world-nuclear.org
- ^ World Nuclear Association: Nuclear Power in Bulgaria
- ^ La storia dei ripetuti incidenti a Majak
- ^ UK-Russia Closed Nuclear Cities Partnership
- ^ Russia shuts second plutonium-producing reactor at Seversk
- ^ BBC: Austria against restarting of nuclear reactor at Mochovce
- ^ YAHOO NEWS: Slovakia forced to restart nuclear reactors after Ukrainian gas crisis
- ^ European Bank for Reconstruction and Development: Breakthrough for Chernobyl nuclear decommissioning efforts (Consortium Novarka to build New Safe Confinement Holtec International to complete Spent Fuel Storage)
- ^ Heuel-Fabianek, B., Kümmerle, E., Möllmann-Coers, M., Lennartz, R. (2008): The relevance of Article 37 of the Euratom Treaty for the dismantling of nuclear reactors. atw - International Journal for Nuclear Power 6/2008
- ^ Le Télégramme: Brennilis
- ^ Ouest-France: "Brennilis : EDF se fait taper sur les doigts"
- ^ ENDS: Nuclear decommissioning funds “require oversight”
- ^ [2]
- ^ Nuclear Decommissioning article by World Nuclear Association (associaciation of nuclear reactors builders: [3]
- ^ Nuclear Decommissioning article by World Nuclear Association (associaciation of nuclear reactors builders: [4]
External links
- decommissioning.info is a portal with information on nuclear decommissioning
- US Nuclear Regulatory Commission
- European website on decommissioning of nuclear installations
- Decommissioning Fund Methodologies for Nuclear Installations in the EU, rapport by the German Wuppertal Institute, commissioned by the European Commission. May 2007.
- Master 'Nuclear Energy' - Decommissioning and Waste management
Categories:- Nuclear technology
- Nuclear power stations
- Radioactive waste
- Nuclear liability
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