Type: RBMK-1000
Units: Four
Total megawatts (net): 3,700 (925 per unit)
Location: Sosnovyy Bor (Russian Federation)
Dates of initial operation:
For an overview of the principal strengths and deficiencies of Soviet-designed plants, see Soviet Nuclear Power Plant Designs.
In March 1992, Unit 3 experienced a fuel channel rupture that was classified as a Level 2 incident on the International Nuclear Event Scale. A March 24 report by the Russian Ministry of Atomic Energy stated that the cause of the incident was a faulty valve. After undergoing maintenance, Unit 3 was shut down until June 1992, when it was brought back up to full power.
In September 1993, the Leningrad plant reportedly had only enough uranium fuel to operate for another three months. The plant had no money to buy fuel because it was owed 26 billion rubles by electricity users. In January 1994, the plant reportedly faced shutdown because of a lack of fuel. In August, the plant director reportedly said that the plant's bank account had been closed because the plant was unable to pay its taxes. In January 1995, the plant reportedly once again faced shutdown because of a lack of fuel. In September 1995, St. Petersburg television reported that the plant had reduced its power output because of fuel shortages.
In May 1995, a report was issued about a reactivity excursion and fuel failure at the plant's Unit 1. According to the Finnish Center for Radiation and Nuclear Safety, the report was a hoax. Unit 1 was shut down in November 1994 for backfitting, and was still shut down at the time of the report. The report was telexed to several foreign nuclear safety organizations by mistake when a plant resident inspector pushed the wrong button in trying to connect a new radiation monitoring system to the plant's satellite connection to the Finnish safety organization.
The Leningrad plant acquired the status of a separate operating utility in 1992, and reports to the Deputy Minister of Atomic Energy as an independent federal enterprise.
The first phase of planned upgrades, which focused on Unit 1, was completed mid-1992. Among key upgrades:
A modernized feedwater system,
Replacement of 1,600 pressure tubes, and
Restoration of graphite blocks in the core and the installation of a new instrumentation and control system.
Unit 1 was taken out of service again in October 1994 for additional improvements: modernization of its reactor control and protection systems, and installation of new equipment for its water-steam separators.
A second phase of upgrades--first for Unit 2 and then for Unit 3--began in 1992. These involve:
Seismic and fire protection improvements, and
The installation of a new diagnostic system and instrument and control upgrades.
As part of this phase, Unit 2's pressure tubes were replaced. Work on Unit 2 was completed in December 1994. Unit 3 was shut down in July 1995 for replacement of its pressure tubes.
U.S. Aid. In the fall of 1991, the U.S. company General Physics International Engineering & Simulation was awarded a $13 million contract to design an RBMK simulator. The project was expected to take about 3½ years to complete.
Scandinavian Assistance. Representatives from Finland's Center for Radiation and Nuclear Safety joined Russian specialists in August 1992 to check the plant's welding joints. Technicians found no defects.
Finnish and Swedish representatives reported in October 1992 that conditions at the Leningrad plant had been vastly improved. The representatives visited the plant and assessed its quality and safety using International Atomic Energy Agency (IAEA) methodology. The team found plant operation, maintenance and control well-organized and noted that it was being operated in strict compliance with Russian standards. The team noted that plant management had steadily improved plant safety over the past few years, despite adverse conditions in Russia.
In March 1993, Finland's Center for Radiation and Nuclear Safety announced that it had earmarked FM 3.9 million ($873,600) for safety-related improvements at the Leningrad plant. As part of this effort, Finnish fire-fighting experts visited the plant in June 1993 to present proposals on improving fire protection measures. In October, Finland delivered about $100,000 worth of fire-fighting equipment for two units at the plant. Finland's Ministry of Foreign Affairs approved a government grant of FM 1 million ($224,000) to pay for a radiophone system for the plant. The system can be used to support fire-fighting operations as well as in other emergency situations and for testing plant systems.
Japanese Support. In July 1993, Russian and Japanese experts met to discuss the installation of a hybrid sound-pressure noise detection system on Unit 2. In November 1993, Japan agreed to install the system. The cooperative effort is part of the 960 million yen ($8.64 million) cooperative agreement signed between Japan and Russia in March 1991.
European Union Project. British Nuclear Fuels plc (BNFL) and Germany's Nukem GmbH have won contracts worth about DM 4 million ($2.7 million) to manage a project to upgrade fire protection and instrumentation and control systems at the Leningrad plant.
EBRD Project. Through a 2 million ECU ($.. million) project funded by the European Bank for Reconstruction and Development, BNFL and Nukem are helping the plant to develop emergency provisions.
Russian Technical Assistance. The Russian fuel manufacturer, Mashinostroitelniy Zavod Elektrostal, has modified the fuel for RBMK reactors to reduce the void coefficient and thus improve safe operation. A pilot batch of the new fuel was scheduled to be loaded in Leningrad's reactors in December 1995. The results of the test will be analyzed in 1997.
WANO Exchange Visits. The World Association of Nuclear Operators has sponsored several exchange visits involving Leningrad. The plant has hosted personnel from the following plants:
The Leningrad plant also hosted a visit from personnel of the U.S. utility Commonwealth Edison in August 1995.
In addition, personnel from Leningrad have visited the following plants:
Plant Twinning. The Leningrad plant is twinned with Germany's Isar 1.
ASSET Mission. An ASSET mission from the IAEA visited the Leningrad plant May 17-28, 1993. The team reviewed 327 operational events that occurred between January 1982 and April 1993, of which 152 were determined to be safety relevant. Of these, 144 were classified as Level 0 on the International Nuclear Event Scale (INES), seven were classified as Level 1 and one was classified as Level 2. The team felt it was significant that nearly 40 percent of the events had occurred at Unit 1. As a result of its analysis, the team identified five categories of recurrent events: short circuits, human failures, failures in electronic systems, bearing problems, and refueling problems.
The team also identified five safety problems that were undermining the plant's safety performance:
Compartmentalized plant organization, with complex interface problems.
No obvious regular and systematic reappraisal of the safety case to identify challenges to or inadequacies of the original safety acceptance criteria.
Lack of safety culture.
Lack of an effective surveillance scheme to identify potential weaknesses and possible initiators of events.
Lack of detailed operating procedures.
The team concluded that the plant has the basic ingredients of a policy to improve safe and reliable operation, and it was satisfied with the appropriateness of most corrective actions implemented as a result of the lessons learned from the operational events. But it identified pending safety problems in the areas of reliability of equipment, personnel and procedures.
The team developed an action plan with recommendations for optimizing the balance between software and hardware safety provisions, for improving the plant program to prevent latent weaknesses, for improving feedback from operating experience, and for improving the quality of documentation. The team recommended a follow-up mission in two to three years to assess the progress made by the plant.
Planned Follow-Up ASSET Mission. A follow-up mission is scheduled for June 3-7, 1996.
December 1995
