Fukushima Daiichi Unit 3
E231223
Fukushima Daiichi Unit 3 is one of the damaged reactors at Japan’s Fukushima Daiichi Nuclear Power Plant, known for suffering a hydrogen explosion and core meltdown during the 2011 nuclear disaster.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Fukushima Daiichi Unit 3 canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T1979335 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Fukushima Daiichi Unit 3 Context triple: [Fukushima Daiichi nuclear disaster, affectedReactor, Fukushima Daiichi Unit 3]
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A.
Fukushima Daiichi Unit 2
Fukushima Daiichi Unit 2 is one of the damaged reactors at Japan’s Fukushima Daiichi Nuclear Power Plant that suffered a core meltdown and severe structural failures following the 2011 earthquake and tsunami.
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B.
Fukushima Daiichi Nuclear Power Plant
Fukushima Daiichi Nuclear Power Plant is a coastal Japanese nuclear power station in Ōkuma, Fukushima Prefecture, widely known as the site of the 2011 reactor meltdowns following a massive earthquake and tsunami.
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C.
K-East Reactor
K-East Reactor was one of the plutonium production reactors at the Hanford Site in Washington State, built during the Cold War to support the U.S. nuclear weapons program.
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D.
K-West Reactor
K-West Reactor is one of the plutonium production reactors at the Hanford Site in Washington State, historically used to support the U.S. nuclear weapons program.
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E.
D Reactor
D Reactor was one of the early plutonium production reactors at the Hanford Site in Washington, built during the Manhattan Project to support the U.S. nuclear weapons program.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Fukushima Daiichi Unit 3 Target entity description: Fukushima Daiichi Unit 3 is one of the damaged reactors at Japan’s Fukushima Daiichi Nuclear Power Plant, known for suffering a hydrogen explosion and core meltdown during the 2011 nuclear disaster.
-
A.
Fukushima Daiichi Unit 2
Fukushima Daiichi Unit 2 is one of the damaged reactors at Japan’s Fukushima Daiichi Nuclear Power Plant that suffered a core meltdown and severe structural failures following the 2011 earthquake and tsunami.
-
B.
Fukushima Daiichi Nuclear Power Plant
Fukushima Daiichi Nuclear Power Plant is a coastal Japanese nuclear power station in Ōkuma, Fukushima Prefecture, widely known as the site of the 2011 reactor meltdowns following a massive earthquake and tsunami.
-
C.
K-East Reactor
K-East Reactor was one of the plutonium production reactors at the Hanford Site in Washington State, built during the Cold War to support the U.S. nuclear weapons program.
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D.
K-West Reactor
K-West Reactor is one of the plutonium production reactors at the Hanford Site in Washington State, historically used to support the U.S. nuclear weapons program.
-
E.
D Reactor
D Reactor was one of the early plutonium production reactors at the Hanford Site in Washington, built during the Manhattan Project to support the U.S. nuclear weapons program.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
boiling water reactor
ⓘ
nuclear reactor unit ⓘ |
| accidentConsequence |
core meltdown
ⓘ
hydrogen explosion ⓘ |
| accidentDate | 2011-03-11 ⓘ |
| accidentType | loss-of-coolant accident ⓘ |
| commercialOperationStartDate | 1976 ⓘ |
| constructionStartDate | 1967 ⓘ |
| containmentType | Mark I containment ⓘ |
| containmentVenting | attempted containment venting during accident ⓘ |
| coolingLossCause | tsunami-induced station blackout ⓘ |
| country | Japan ⓘ |
| decommissioningStatus | under decommissioning ⓘ |
| earthquakeMagnitude | 9.0 ⓘ |
| electricalCapacity_MWe | 784 ⓘ |
| emergencyResponse | sea-water injection into reactor core ⓘ |
| firstGridConnectionDate | 1974 ⓘ |
| fuelType |
mixed oxide fuel
ⓘ
uranium dioxide ⓘ |
| gridConnectionStatus_postAccident | disconnected from grid ⓘ |
| hydrogenExplosionDate | 2011-03-14 ⓘ |
| hydrogenExplosionEffect |
release of radioactive materials to environment
ⓘ
severe damage to reactor building superstructure ⓘ |
| INESRating_contextPlant | part of site rated level 7 on INES scale ⓘ |
| location |
Ōkuma, Fukushima Prefecture
ⓘ
surface form:
Ōkuma, Fukushima Prefecture, Japan
|
| neighboringUnits |
Fukushima Daiichi Unit 2
ⓘ
Fukushima Daiichi Unit 4 ⓘ |
| operator |
Tokyo Electric Power Company
ⓘ
surface form:
TEPCO
Tokyo Electric Power Company ⓘ |
| partOf | Fukushima Daiichi Nuclear Power Plant ⓘ |
| postAccidentStatus | fuel debris present in reactor pressure vessel and containment ⓘ |
| reactorSupplier | Toshiba ⓘ |
| reactorType | BWR-3 ⓘ |
| regulatoryBody |
Nuclear Regulation Authority (Japan)
ⓘ
surface form:
Nuclear Regulation Authority of Japan (post-reorganization)
Nuclear and Industrial Safety Agency ⓘ
surface form:
Nuclear and Industrial Safety Agency of Japan (at time of accident)
|
| remoteDebrisRemoval | used remote-controlled equipment for rubble removal ⓘ |
| safetySystemFailure |
failure of emergency core cooling
ⓘ
loss of off-site power ⓘ |
| shutdownReason | Fukushima Daiichi nuclear disaster ⓘ |
| siteReactorCount | one of six reactors at Fukushima Daiichi ⓘ |
| spentFuelPoolLocation | upper part of reactor building ⓘ |
| spentFuelPoolStatus_postAccident | intact but structurally affected by explosion ⓘ |
| status | permanently shut down ⓘ |
| thermalCapacity_MWt | 2381 ⓘ |
| tsunamiCause |
2011 Tōhoku earthquake and tsunami
ⓘ
surface form:
2011 Tōhoku earthquake
|
| tsunamiDate | 2011-03-11 ⓘ |
| uniqueFeature | only MOX-fueled unit at Fukushima Daiichi at time of 2011 accident ⓘ |
| usesMOXFuel | true ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Fukushima Daiichi Unit 3 Description of subject: Fukushima Daiichi Unit 3 is one of the damaged reactors at Japan’s Fukushima Daiichi Nuclear Power Plant, known for suffering a hydrogen explosion and core meltdown during the 2011 nuclear disaster.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.