Episode:
66
Leningrad Unit 1
Country:
USSR/Russia
Years of Operation:
1973-2019
Category:
Commercial & Power
Reactor Type:
Coolant:
Light Water
Fuel Type:
Enriched Uranium
Moderator:
Graphite
Thermal Power (MWth):
3200
Electrical Power (MWe):
3200
Status:
Commercial & Power
timeline
First Criticality Year
1973
Commercial Op Year
1974
Shutdown Year
2019
Lessons Learned
1.Physics doesn't care about your ideology. You can classify documents, but you cannot
classify neutron flux.
2.Near-misses are gifts. If you survive a partial meltdown, that is the universe giving you a second chance. Don’t waste it by shredding the evidence.
3.The "Precursor" Argument. Every major industrial disaster usually has a quiet older brother that nobody listened to. Find yours before he starts shouting.
Unit 1 is gone now, shut down in 2018. But let it be a reminder: The only thing more dangerous than a positive void coefficient is a negative transparency coefficient.
sources
ARTICLE
Sometimes history whispers before it screams.
Let’s talk about the Leningrad Nuclear Power Plant Unit 1.
You know the RBMK-1000. It’s the reactor design that eventually gave HBO a hit miniseries and
the Soviet Union a permanent headache. But before Chernobyl became a household name for "oops," there was Leningrad 1—the prototype, the trailblazer, the first-born child of a very dysfunctional family.
The Tale of the Tape:
•Construction Started: March 1, 1970 (The 70s were wild).
•First Criticality: September 12, 1973.
•Grid Connection: December 21, 1973.
•Power: 3200 MWth / 1000 MWe (Gross).
•Reactor Type: RBMK-1000 (Light Water Graphite Reactor).
•Status: Finally put out to pasture on December 22, 2018.
For a couple of years, it ran like a typical Soviet machine: loud, large, and terrifyingly utilitarian.
But the real "fun" started in November 1975.
During a startup after maintenance, the operators got into a bit of a tussle with the controls. A turbogenerator trip led to a power reduction, and in the process of trying to bring the beast back up, they managed to put the reactor into that sweet, unstable spot we all know and loathe: low power, high xenon, and a positive void coefficient that was ready to party.
Sound familiar? It should.
On November 30, 1975, the reactor suffered a localized power excursion. A fuel channel ruptured. The graphite stack degraded. It was a partial meltdown. It was, mechanically and physically, the exact same accident sequence that would tear Chernobyl Unit 4 apart eleven years
later.
But here is where the story diverges. At Leningrad, the beast only bit off a finger instead of the whole hand. The radiation release was significant (about 1.5 million Curies, depending on which secret report you don't read), but it didn't empty the Ukraine.
So, did the Ministry of Medium Machine Building shout from the rooftops? Did they warn the operators at Kursk and Chernobyl that the RBMK had a "self-destruct" button installed at low power?
Of course not. They mopped it up, fired the guys who asked too many questions, and stamped the report "Top Secret." They fixed the singular unit but left the fatal design flaw in every other RBMK across the USSR because retrofitting is expensive and admitting failure is counter-
revolutionary.
SLIDE DECK
