Glitching safety system at Russia’s aged Bilibino NPP causes emergency reactor shutdown

Bilibino NPP, which runs four EGP-6 reactors, is located in Russia’s Far Northeast, in Chukotka Autonomous District, which is beyond the Arctic Circle. Erected on permafrost, the station is the smallest and the northernmost operating nuclear power plant in the world.

Bilibino NPP, which runs four EGP-6 reactors, is located in Russia’s Far Northeast, in Chukotka Autonomous District, which is beyond the Arctic Circle. Erected on permafrost, the station is the smallest and the northernmost operating nuclear power plant in the world.

According to reports by the public information service of the Russian NPP operator, concern Rosenergoatom, and the press service of Bilibino’s production and engineering department, the scram occurred on October 27, 2010 at 07:12 p.m. local time. The reactor was taken back online on October 29 at 05:32 a.m. local time. The scram was ascribed to a “false signal generated by the protection equipment.” The reactor was thus offline for 34 hours, providing no power or heat to the Chaun-Bilibino energy system.

Scramming after repairs

One circumstance that causes additional concerns regarding the latest shutdown at Bilibino is that it occurred only two weeks after three-day unscheduled repairs – October 11 through 14 – ended at the reactor. There have been no reports as to why the repairs were needed in the first place.

It can be speculated that the repairs had to do with modernising the very protection and safety systems which generated a false alarm signal and brought the reactor down on October 27.

No upgrades for Bilibino’s safety systems since 1973

Reactor Unit 2 at Bilibino NPP was commissioned in 1974. According to design projections, it was supposed to have run out its 30-year operational lifetime in 2004, and decommissioned after that. However – as has been common enough practice at Russian nuclear power plants, such as Kola NPP in Murmansk Region in Russia’s Far North – the reactor’s license was extended, allowing it to operate for another 15 years, or until 2019.

Bilibino NPP, which runs four EGP-6 reactors, is located in Russia’s Far Northeast, in Chukotka Autonomous District, which is beyond the Arctic Circle. Erected on permafrost, the station is the smallest and the northernmost operating nuclear power plant in the world.

Bilibino NPP, which runs four EGP-6 reactors, is located in Russia’s Far Northeast, in Chukotka Autonomous District, which is beyond the Arctic Circle. Erected on permafrost, the station is the smallest and the northernmost operating nuclear power plant in the world.

its measures for bringing its equipment into compliance with nuclear safety standards.”

The more detailed Russian version of the same statement elaborated that the automatic regulation and emergency protection functions will be implemented in the new systems, which will be based on “modern hardware components” and will enhance the equipment’s reliability.

The logic and the functional characteristics of the modernised safety equipment will fully correspond to the prototype, only the replacement for modern-type equipment will be implemented, the statement said.

All of this means that the ancient equipment, designed in the 1960s and produced in the early 1970s, will simply be replaced with newly made analogues based on “modern hardware components.”

It remains uncertain whether electronic or computer-based safety systems will ever be installed at Bilibino. What is clear for the moment is that with all the modernisation done by mid-October, the equipment continued to glitch and caused an emergency shutdown of the reactor.

Can one really trust the industry’s reports?

As circumstances would have it, it was only one week prior to the unscheduled repairs and three weeks before the reactor was scrammed due to a false alarm signal from the emergency protection systems that the PR service of Bilibino’s production and engineering department issued a report – written in the best traditions of Soviet-style eyewash and window-dressing – attesting to the NPP’s readiness to operate safely and reliably (quoted here verbatim):

“An inspection commission on readiness of nuclear plant power units for operation under autumn-winter peak load […] in 2010-2011 has finished its work at Bilibino NPP […]. In accordance with the results of the performed inspection the plant was acknowledged to be ready to securely carry electric and thermal power load in the autumn-winter period: the commission recommended issuing to Bilibino NPP of a passport of operational readiness for [autumn-winter peak load] 2010-2011.”

What this amounts to is nuclear officials gathering their own commissions, paying inspection visits to each other’s sites, issuing each other “passports of operational readiness,” or “passports of quality performance,” or “ecological safety passports” – but these reports may not be worth the paper they are printed on. Experience shows, after all, that at least Reactor Unit 2 of Bilibino NPP was not ready to “securely carry” its power load.

One question persists as to what would happen if the nuclear industry dared to expose its inner workings to the scrutiny of a fully independent commission, or if, before the dangerous operational license extensions were issued, the operator company had had courage enough to apply for a law-mandated state environmental impact evaluation. Would the reality of the situation make it into the public domain? Would the aged reactors at Bilibino have been stopped and decommissioned when their engineered life spans had expired?

This is what Vladimir Kuznetsov, D. E. Sc., a former atomic industry oversight specialist, says on the matter:

“Most of the equipment at the reactor units of Bilibino [NPP] has exhausted or soon will exhaust its [operational] resource. The reactors do not meet the requirements of safety rules and standards, and there is no making them comply with said requirements.”

How good an idea is having a polar-based nuclear power plant?

Bilibino NPP was built beyond the polar circle, in an area covered by permafrost, in Chukotka Autonomous District. There are risks to its safety and integrity beyond the common equipment failures plaguing Russian nuclear power plants – namely, global warming. As permafrost melts, even partial thawing can cause thermokarst to appear – very irregular surfaces of marshy hollows and small hummocks formed as a result of thawing ice-rich permafrost. The melting permafrost phenomenon already presents a grave danger for Russian towns and cities in the far north, where buildings and infrastructure – including oil production and transport facilities – are predicted come under threat as the ground beneath becomes unstable. Should such risks loom close over Bilibino, the reactors will have to be shut down anyway: No listing is permissible for a structure as sensitive and potentially hazardous as a nuclear power plant.

Bilibino employs four low-capacity graphite-moderated boiling-water reactors for combined heat and power of a Soviet design known as EGP-6. Each reactor has a heat-generating capacity of 62 megawatts. A reactor unit with such a reactor in operation can run in an alternating load mode and produce up to 12 megawatts of electric power and up to 29 megawatts of heat.

The low capacity was chosen for this design in order that the power plant would have all four reactor units at its disposal and that frequent unplanned shutdowns would not destabilise the isolated energy system that the reactors supply electricity and heat to.

The ideology behind this stems from a decision made decades ago, during Soviet time, to build four-unit nuclear power plants, the kind that would abide by the following rule in their operation: one unit under repairs, another in reserve, and two more in normal running mode.

It is possible that, given the characteristic unreliability of reactors operating at Russian nuclear power plants, this decision is the sole one that could guarantee stable energy supply, but the never-ending stretches of equipment downtime lend a considerable degree of commercial untenability to a nuclear energy industry built on such principles.

Bilibino NPP’s own performance last October is a telling illustration. According to a Rosenergoatom statement, “in October this year, reactor units of Bilibino NPP produced 13.85 million kilowatt-hours of energy.” If all four of the plant’s reactors had been working non-stop throughout October, the amount of energy produced would have more than twice exceeded the actual output, reaching 35.712 million kilowatt-hours.

In October, the plant was operating with a record low installed capacity utilisation ratio – just 38.8 percent. And a low capacity factor spells high prices for heating and power…

Bilibino NPP: A high achiever in radioactive discharges, waste, and radiation exposure records?

Bilibino production premises are located just 3.5 kilometres east of the city limits of the town of Bilibino. The 2009 yearly report published by Rostekhnadzor, the Russian Federal Service for Ecological, Technological, and Atomic Supervision (to download the Russian version of the report, please follow the link on the right), says last year, Bilibino NPP’s emissions amounted to more discharges of radioactive inert gases (including Krypton 85) per one unit of power than those of any other of the ten nuclear power plants in operation in Russia. Running on a combined heat-producing capacity of 250 megawatts that its four reactor units provide, Bilibino NPP emitted 361.1 terabecquerels in radioactive inert gases into the surrounding atmosphere.

By comparison, Kursk and Leningrad nuclear power plants, both fifty times as powerful as Bilibino, and each, too, employing graphite-moderated reactors with a combined heat capacity of 12,800 megawatts, reported much lower levels of radioactive inert gas emissions in 2009: 297.3 terabecquerels and 252.4 terabecquerels, respectively.

Needless to say, the immediate “consumers” of Bilibino’s radioactive emissions were, depending on wind direction, either the Chukotka environment or residents of the nearby town of Bilibino.

Furthermore, Rostekhnadzor states in its report that it was precisely during modernisation works performed at this old and dangerous nuclear power plant in 2009 that its employees received maximum radiation exposure doses:

“The maximum individual doses of exposure to radiation received while engaged in equipment repairs were received in the reported period by the core and temporary personnel at Bilibino NPP (4.44 microsieverts and 3.29 microsieverts respectively).

In 2009, while performing cleaning work on the internal components of the steam drum at Reactor Unit 1 of Bilibino NPP, five employees of Atomenergoremont [a leading nuclear equipment repair and maintenance company] sustained exposure to individual radiation doses that exceeded control levels established at the NPP and equalling 20 microsieverts. The peak individual exposure dose, absorbed radiation included, reached 38.2 microsieverts.”

As a result of the excessive staff exposure levels at Bilibino, Rostekhnadzor’s report said, an investigation was initiated as required by industry guidelines. The investigation revealed that the radiation exposure “control level was exceeded due to insufficient supervision of the works in progress and inefficient use of means of individual protection by the personnel.”

As if the radioactive discharges and personnel radiation exposure were not enough, there is yet another problem Bilibino NPP is having a tough time with: Nuclear waste and spent nuclear fuel. Spent fuel is not removed from the plant and on-site storage facilities are filling up. Bilibino desperately needs a new, fourth cooling pond to store its spent nuclear fuel in – but there is no clarity as to how this waste will be handled in the medium and long term.

A floating NPP to replace the outgoing Bilibino?

License extensions or not, Bilibino NPP’s reactors will sooner or later have to be shut down for good and decommissioned – and 48 megawatts’ worth of producing capacities will be lost to the isolated Chaun-Bilibino energy hub.

If the development of large gold mines continues in Chukotka – the area is rich in oil, natural gas, coal, gold, and tungsten – the capacities of the remaining 30.5-megawatt Chaun Central Heating and Power Plant may not be enough to supply the needed power.

The Russian nuclear authority, the state corporation Rosatom suggests the port of Peveka, 378 kilometres from Bilibino, could be the place to anchor a floating nuclear power plant – a much hyped-up project it has been developing, currently under completion in St. Petersburg. Earlier, the first potential customer – the Far Eastern region of Kamchatka – begged off when offered to host one such plant, citing prohibitive energy costs.

So far no concrete proposals, other than the notorious floating nuke project, have been forwarded to indicate whether the hazardous Bilibino Nuclear Power Plant will finally retire and a replacement will be found for the area’s energy system – or the history of radioactive discharges, accidents, and radiation exposure will go on into the future.