| June 1998 | - Armenia - Bulgaria - Czech Republic - Hungary | - Kazakhstan - Lithuania - Russia - Slovakia |
- Ukraine - United States - Cross-Cutting Activities - Planned Activities |
Welcome to the June Activity Report, which documents safety improvements achieved in June at Soviet-designed nuclear power plants through U.S. and host-county cooperation. This report replaces the biweekly activity report and is available online or in hard-copy form. To request a hard-copy version or to provide comments or suggestions, send an e-mail message to marye.hefty@pnl.gov.
Repairing the Damaged Ventilation Stack at Chornobyl. In June, workers finished stabilizing a ventilation stack damaged by the 1986 nuclear accident at Chornobyl. The 210-foot-high ventilation stack sits atop a 200-foot-high building between Chornobyl's operating Unit 3 reactor and the "shelter" that encloses the radioactive ruins of Unit 4. The stack still is used in Unit 3 operations.
External braces support the stack and secure it to the building underneath. The braces, however, were damaged in the 1986 explosion. Flying debris severed horizontal bracing, bent and dented diagonal bracing, and tore connections. Vertical supports of the stack's foundation were bent nearly five degrees off alignment.
Calculations showed the stack's stability was reduced by 75 percent. The stack could topple in an earthquake or severe weather, such as high winds or a heavy load of snow. Depending on which way the stack fell, it could injure site personnel and damage either the shelter or the operating Unit 3 reactor. If the stack fell on the shelter, it could damage or crush the roof, sending radioactive dust across the site. If it fell on the operating reactor, it could cause damage to nuclear systems. The repairs restored the stack to its original stability.
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The vent stack damaged in the 1986 accident as shown here has been repaired to its full design strength. |
Repair Approach. Extensive stack repairs were necessary. Nine badly damaged braces needed replacement. The stack's vertical steel foundation supports, bent by the explosion, needed to be stabilized with new concrete foundations. They also needed to be strengthened with vertical metal beams (called "strongbacks") welded along their lengths.
The overriding concern in project planning, however, was the high radiation level around the stack. The explosion imbedded highly radioactive reactor fuel in the stack's paint. To minimize worker exposure, U.S. and Ukrainian experts developed a work plan that included conducting additional decontamination and building a full-size mock-up of a portion of the stack. The mock-up enabled workers to practice repair tasks without exposure to radiation. The work plan also included the development of repair equipment and a parts-delivery system to minimize radiation exposure. Personnel movements and routes through radiation areas were based on ALARA principles—methods for keeping personnel radiation dose "as low as reasonably achievable."
The Chornobyl Shelter Organization developed the original work plan in early 1997 and asked U.S. experts to review it. A team from the Pacific Northwest National Laboratory (PNNL), Chornobyl, and the Ukrainian contractor Ukrenergobud revised the plan to reduce workers' radiation exposure from 4,600 to approximately 400 man-rem. The revised plan also reduced the completion time from 4,200 to 1,700 worker-hours and the projected cost by 50 percent. Chornobyl managers accepted the team's recommendations and made similar comprehensive reviews standard for future high-exposure jobs.
With the concurrence of the G-7 Nuclear Safety Working Group, the United States, Canada, and Ukraine agreed in December 1997 to fund the $2.25 million project. The United States contributed $1 million, Canada $800,000, and Ukraine $450,000.
Repair Schedule. Repair work began on April 23, 1998. The Ukrainian contractor Ukrenergobud is conducting the work, under the technical management of the Shelter Organization. Fifty percent of the repairs were performed by May 9. By June 12, all 20 of the structurally significant damaged sites were repaired by completely replacing nine badly damaged frame members and by welding "strongbacks" over 11 significant dents. The work is expected to restore the structure to 100 percent of its original stability.
Completion of the contract now requires cleanup of the work sites and dismantling of scaffolding, cranes, and the parts delivery system. The project is on schedule for completion in July 1998.
Key Accomplishments. The stabilization of the ventilation stack provided a significant physical improvement to safety at Chornobyl nuclear power plant (NPP). This project demonstrates that Ukrainian organizations can do high-quality project work, on schedule and within budget, as part of an international team.
New Training Course Implemented at Kola. The first week in June, training experts from General Physics Corporation, PATH Training, and Balakovo NPP worked at Kola NPP with training staff from the plant to finalize training materials for the mechanical maintenance pilot training course on laser alignment of rotating equipment. The pilot course was implemented during the second week of June. (Peter Kohut, BNL, 516-344-4982)
Balakovo-Developed Manual Reviewed. U.S. experts and Balakovo NPP staff met at the plant in mid-June to review an administrative procedures manual developed by Balakovo NPP. The document will be used by the Russian NPPs in developing consistent administrative procedures relative to training program development and implementation. (Peter Kohut, BNL, 516-344-4982
Factory Acceptance Test Complete for Novovoronezh Analytical Simulator. In June, the factory acceptance test for the Novovoronezh analytical simulator was completed at the subcontractor's facility in Moscow. During July, the simulator will be packed and shipped to Novovoronezh NPP where site acceptance testing will take place. The system is scheduled to be ready for training by the end of July. (Peter Kohut, BNL, 516-344-4982) Smolensk Fire Hazards Analysis Reviewed. Progress on the safe shutdown analysis for Smolensk Unit 3 was reviewed by the Coordinating Committee on June 2 and 3, 1998, at the VNIIAES facility in Moscow. Representatives from VNIIAES, Atomenergoproekt, Smolensk NPP, Bechtel National, Engineering Planning Management, and the U.S. team participated in the review. Comments by the U.S. reviewers on the first three task reports for the project were discussed and resolved satisfactorily. The project is approximately two months behind schedule, in part because of the size of the list of potential safe shutdown equipment. At the suggestion of the reviewers, this list will be prioritized to decrease the overall effort. The results of visual tracing of cables indicate that the facility drawings are accurate for the fire zone through which the cables pass. The cable tracer provided to the plant will be used to complete the tracing of cables in an upcoming outage. (Andy Minister, PNNL, 509-376-4938)
Circuit Breaker Technology Transfer Continues. U.S. team representatives met with Russian participants (Rosenergoatom, Elox, Plant Progress, Inc., Atomenergoproekt, and Smolensk NPP) in the circuit breaker technology transfer project in Moscow on June 2 to 5. The Elox company has responsibility for the design of trolleys that interface with 6-kV Western circuit breakers and for performing certification tests. Negotiations between Bechtel National and Elox are proceeding well for these activities. Plant Progress has a similar role for the high-amperage 0.4-kV circuit breakers. The U.S. participants visited the Plant Progress facilities and reviewed a draft of their proposal. The host-country management has not been finalized for the in-plant licensing test program for the low-amperage 0.4-kV circuit breakers. (Ron Wright, PNNL, 509-372-4076)
RELAP5 Code Being Validated for Russian Application. Two code validation plans for application of RELAP5 to Soviet-designed reactors were completed at the Russian International Nuclear Safety Center (RINSC) in Moscow, June 10-11. Representatives from RINSC, Electrogorsk Research and Engineering Center, Kurchatov Institute, Research and Development Institute of Power Engineering, and the U.S. team participated in the meeting. Review comments on the draft version of the validation plans were discussed and resolved. In late June, RINSC prepared the final version of the RELAP5 validation plans for application to RBMK reactors. The final version of the plans for VVER reactors will be available in early July. (Jordi Roglans, ANL, 630-252-3283)
In-Depth Safety Assessments Reviewed. U.S. team members and participants in both the Kola in-depth safety analysis (KOLISA) project and the Novovoronezh in-depth safety analysis (NOVISA) project met June 22 through 27 in Moscow. The meetings were held with subcontractors to Kola NPP to discuss the development of the RELAP5 models for carrying out design basis accident (DBA) calculations for Kola NPP Units 1 and 2. They also met with members of the Kola NPP team from the Kurchatov Institute who are completing the RELAP5 model for Kola Unit 4 as part of Phase I of the KOLISA project. The meeting was a follow-up to a previous meeting in March.
While in Moscow, U.S. specialists also met with members of the NOVISA project to help them plan the development of the RELAP5 model of the Novovoronezh Unit 3. The NOVISA team is improving a RELAP5 model developed at a previous training course in 1996. The team intends to use this model for the NOVISA project success criteria calculations in the probabilistic risk assessment for Units 3 and 4 and for DBA calculations for these units. (Ross Jensen, ANL, 208-526-7911; Phillip Pizzica, ANL, 630-252-4847)
Radiation Protection Inspection Plan Under Development. From June 23 to July 3, U.S. specialists are conducting a workshop in Washington, D.C., with Gosatomnadozor (GAN, which is the Federal Nuclear and Radiation Safety Authority of Russia) to develop a radiation protection inspection plan as a template for GAN and for future inspection efforts. The participants will also conduct a pilot inspection of hot cell facilities at Argonne National Laboratory-West in Idaho Falls. (Ed Branagan, DOE, 301-903-6509; George Vargo, PNNL, 509-375-6836)
Establishment of New Operational Safety Infrastructure. On June 8 through 12 during meetings in Atlanta, Georgia, and Richland, Washington, U.S. and Ukraine representatives identified actions to improve the operational safety infrastructure in Ukraine. Participating organizations included Energoatom, the State Scientific and Technical Center for Nuclear and Radiation Safety (SSTC-NRS), the new Nuclear Power Plant Operational Safety Institute (NPP OSI), the U.S. Institute of Nuclear Power Operations (INPO), World Association of Nuclear Operators (WANO), and PNNL. During the discussions in Atlanta, the Ukrainian participants were informed about the operational support functions provided to U.S. plants by INPO and available to Ukrainian plants from WANO. The meetings with PNNL in Richland defined tasks necessary to develop the capabilities of NPP OSI to support Energoatom and the Ukrainian NPPs. (Bob Moffitt, PNNL, 509-372-4108; Don Draper, PNNL, 509-372-4079; Lief Erickson, PNNL, 509-372-4097)
First Software Quality Assurance Plan for Ukraine Completed. In early June, the Ukrainian contractor INIT completed the first software quality assurance (QA) plan for Ukraine. This QA plan will be used throughout the development and operation of the Ukraine reliability database. This database will contain performance reliability information on safety-related components of mechanical, electrical, and instrumentation systems. (Grigory Trosman, DOE, 301-903-3581; Thomas Vehec, PNNL, 509-372-4072)
South Ukraine Implements New Training Course. In June, training staff from South Ukraine NPP implemented the pilot training course on instrumentation and controls: integrated-circuit board repair. This accomplishment completes the first phase of the training technology transfer project in Ukraine. Also participating in this implementation at South Ukraine were training experts from General Physics Corporation and PATH Training. (Peter Kohut, BNL, 516-344-4982)
Efforts Made to Simplify EOI Regulation. A new task order is being developed for the State Scientific and Technical Center (SSTC) to support the expansion of the emergency operating instruction (EOI) regulation in Ukraine to include the RBMK and VVER reactors. The VVER EOI regulation has been drafted by SSTC and approved by the Nuclear Regulatory Administration. The regulation awaits approval from the Ministry for Environmental Protection and Nuclear Safety. Flow-charted symptom-based EOIs have been implemented at Chornobyl under existing regulation, but the Ministry's intent is to have uniform regulation that encompasses all types of EOIs.
At the request of SSTC and to support the technology transfer process for this activity, a workshop is scheduled for the week of July 20 through 24. Representatives from SSTC will participate in two days of classroom training in Richland, Washington, provided by the U.S. team. During these classroom presentations, the methodologies associated with flow-charted EOIs will be explained. Following the classroom presentations, the SSTC representatives will travel to three U.S. utilities where they will observe simulated use of the boiling water reactor flow-charted EOIs at Hope Creek NPP and the flow-charted Westinghouse EOIs at Salem NPP. Following the simulator exercises at Hope Creek and Salem NPPs, the Ukrainians will travel to Seabrook NPP, where they will observe a simulated demonstration of the dual-column Westinghouse EOIs.
These comparative exercises are being planned to demonstrate the similarities of both types of EOIs and to simplify the EOI regulation process in Ukraine. The current schedule calls for all EOI regulation to be fully implemented in Ukraine by January 1999. (Kent Faris, PNNL, 509-372-4068)
Safety Parameter Display System Projects Forge Ahead. On June 18, the South Ukraine Unit 1 safety parameter display system (SPDS) successfully completed the site acceptance test for Phase I operation. The system subsequently was approved for operation by the state inspectors and state licensed metrology service.
The system is being implemented in three phases: Phase I involved mostly hardware (e.g., signal cable) installation and implementation of 8 critical safety parameters. Phase II is scheduled to be implemented during power operation this summer and will involve completing another 15 safety parameter displays. The final phase is scheduled for the winter outage. When completed, the SPDS will monitor a total of 38 critical safety parameters.
Staff from DOE, PNNL, Burns & Roe Enterprises, Inc., TriTech, Westinghouse Electric Corporation, Westron, Energoatom, and South Ukraine Unit 1 participated in the design, fabrication, software development, factory testing, shipping, installation, and testing at the reactor.
In other SPDS projects, staff from DOE, PNNL, Burns & Roe Enterprises, Inc., TriTech, Westinghouse Electric Corporation, Westron, Energoatom, Ukraine SSTC, Ukraine State Scientific and Engineering Center, and the NPPs participated in pre-factory acceptance test meetings in Kyiv on June 9 and in Kharkiv on June 10 and 11. The meetings were held to discuss the status of SPDS hardware assembly, functional design, licensing, factory acceptance testing, installation, and site acceptance testing for the two VVER-1000 pilot systems to be implemented at Khmelnytskyy Unit 1 and Zaporizhzhya Unit 5. These topics were reviewed also for South Ukraine Unit 1, which will implement the first phase of its SPDS in the current year. Substantial progress has been made on the assembly and testing of the two pilot plant systems, and the factory acceptance tests are expected to be completed within two weeks.
In addition to accomplishments at the NPPs mentioned above, the U.S. team also is authorizing the purchase of SPDSs for installation at South Ukraine Unit 2, Rivne Unit 3, and Zaporizhzhya Unit 3 in 1999. (Mike Durst, PNNL, 509-372-4698)
Code Validation Work Continues for VVER Application. The potential definition of a standard problem for RELAP5 validation was discussed in Kyiv on June 8 and 9. The definition under consideration is based on actual plant transient data from a Ukrainian NPP. Participants included the Nuclear Power Plant Operations Support Institute (NPP OSI), Rivne NPP, and U.S. team representatives. Participants discussed in detail the scope of work for both Ukrainian organizations. The NPP OSI and Rivne NPP will review the scope of work and provide comments for the completion of the statements of work. (Jordi Roglans, ANL, 630-252-3283)
Guidelines Completed for Rivne In-Depth Safety Assessment. In early June, Ukrainian experts completed preparing detailed project guidelines for both quality assurance and specific technical work to be performed for the in-depth safety assessment at Rivne NPP. (Charles Dickerman, ANL, 630-252-4622)
Computer Code Transfer Approved for Ukrainian In-depth Safety Assessments. The Oak Ridge Radiation Safety Information Computational Center has approved transfer of the computer code ORIGEN for use in the in-depth safety assessments being performed for Rivne and Khmelnytskyy NPPs. Eventually, this code will be transferred for in-depth safety assessments at South Ukraine and Zaporizhzhya NPPs. ORIGEN is a code that calculates the radioactive inventory in NPPs for use in estimating radioactive releases under various accident situations. (Charles Dickerman, ANL, 630-252-4622)
First Cask Successfully Poured at Zaporizhzhya NPP. The first ventilated concrete cask was poured successfully at Zaporizhzhya NPP. With completion of this task, Zaporizhzhya NPP has all the cask components and ancillary equipment required to initiate dry storage of spent fuel at the Zaporizhzhya NPP site. Once the concrete cask has cured and an operating license for the dry storage system has been received from the Ukrainian regulator, Zaporizhzhya NPP will be in a position to load the first dry storage cask, which could happen as early as July 1998. (Mike McKinnon, PNNL, 509-372-4198)
Chornobyl Initiatives
Factory Acceptance Test Being Conducted for Chornobyl SPDS. The factory acceptance text for the Chornobyl SPDS is being conducted June 29 through July 1 at the Westron facility in Kharkiv, Ukraine. Following completion of this test, the equipment will be shipped to Chornobyl for installation during a shutdown scheduled for later this calendar year. (Rich Denning, PNNL, 614-424-7412)
Chornobyl Shelter Developing Radiation Protection Program. From May 25 through June 5, training experts from Sonalysts, Inc. worked at the Chornobyl Shelter developing training materials for a Radiation Protection Technician pilot training program. The pilot course will take into account the unique environment encountered in the shelter. The pilot course will be implemented this fall. (Peter Kohut, BNL, 516-344-4982)
Equipment Released from Customs. In early June, the insulation testing equipment was released from Ukrainian customs, and now it is ready for installation at Chornobyl Unit 3. This equipment identifies insulation breakdown and alerts operators to the degradation. Arrangements with the manufacturer are in progress to complete this installation in a timely manner. (Ray Pugh, PNNL, 509-372-4103; Thomas Vehec, PNNL, 509-372-4072)
Installation of STREAM Code Begins at Chornobyl. From June 1 through 20 at Chornobyl NPP, U.S. experts began installing the STREAM computer code and training Chornobyl Shelter staff in its use. STREAM is an acronym for System for Tracking Remediation, Exposure, Activities, and Materials. As a management software program for decontamination and decommissioning projects, STREAM provides graphic representations of site-specific radiological conditions, facilities, layout, and tracking. (George Vargo, PNNL, 509-375-6836)
Quality Assurance Checked for Armenia Construction Project. A QA training session was held for the deputy director and construction manager of the Armenia NPP during the week of June 1 at the Burns & Roe offices in Oradell, New Jersey. The Armenian Nuclear Regulatory Authority had indicated concern about the extent to which Western QA practices were being used in the nuclear service water system construction project under way at Armenia NPP. This major construction project will provide spray cooling ponds at the plant for the rejection of safety-related heat loads. The purpose of the training session was to identify any deficiencies that might exist in the current program and to assist the plant in upgrading its practices. In addition to receiving two days of QA training, the Armenians visited a Burns & Roe construction site and Indian Point 3 NPP. (Rich Denning, PNNL, 614-424-7412)
Ignalina Staff Complete Training Workshop. In June, U.S. training specialists conducted a four-week workshop on the Systematic Approach to Training (SAT) methodology for personnel from Ignalina NPP. This training took place at the General Physics Corporation offices in Aiken, South Carolina. The workshop is the initial activity as part of a joint U.S. Department of Energy and International Atomic Energy Agency project to improve training capabilities at Ignalina NPP. Participants attended modules on job/task analysis, course design and development, instructor skills, on-the-job training, and test development. In addition, participants began developing course materials for the Control Room Reactor Operator position. The course materials will be completed during three additional working visits to Ignalina NPP, culminating in a pilot program presentation. (Peter Kohut, BNL, 516-344-4982)
