Proj UK/TS/12 - assistance Ukraininian

After the 1986 accident at the Unit 4 at the Chernobyl site, Ukrainian and Russian authorities constructed a new “containment" for the damaged reactor. This structure (the Ukritiye) was erected in great haste and under extremely arduous conditions. Subsequent monitoring and analysis of the Ukritiye has shown that the initial expectation of a 30 year lifetime was unlikely to be achieved.
The International Community and the Ukrainian Authorities agreed on a combination of short and long term measures for the reparation of the damaged structures and their safe operation or encasement.
One of the first priorities for any safety assessment and upgrading of the Ukritiye was to develop a set of safety objectives for such “special” facility and for the encasement (the so called “Shelter structure”), for the short term and long term measures, based on both a general analysis of external hazards and a tentative classification of the main risks posed to the environment, population and workers.

These safety objectives supported the definition of "Design criteria" by the team of international experts in charge of the design assessment (see relevant PRSs).

In general terms, safety objectives mean general requirements (of the regulatory administration) for the design, construction and operation of anything related to the object "Shelter". The main goal of these safety objectives is to allow the operator and designers to define solutions so that the hazards should remain acceptable regarding their radiological consequences for the workers, the population (including future generations) and the environment.

More specifically, the safety objectives had to address the fact that the sarcophagus (Shelter including the remains of unit 4) is not an operating nuclear facility but a temporarily confined destroyed reactor, and that there is also a post-accidental contamination of the environment. Despite of this special nature, all activities should meet the generic recommendations for dose limits to workers and population.

This project is a follow-up of the project CHE-93 in the sense that it revised the general safety objectives for the Shelter. However, it also supported the NRA in the licensing of the SIP and issued essential guidelines for the development of the very peculiar Safety Analysis Report (SAR) of the Shelter..

Additional information on the project background is also provided in the PRSs of the project 97-0077, 94-0699, and CHE-93.

The generic project objective was to provide assistance to NRA for all licensing activities during the development and implementation of the Shelter Implementation Plan (for its definition see project 97-0077).

In particular the objective of this project was to assist the NRA, in cooperation with SSTC, in reviewing the documents prepared by the industrial contractors, to bring NRA in a position to give the approval for the different steps during the licensing procedure of the SIP.

This was done by:

• preparing decisions by proposals and comments
• transferring Western know-how to SSTC
• The planned output of the project is the following:
• a series of comments on SIP drafts and on technical specifications of the early biddable projects
• proposals of and comments to licensing procedure related documents.
• minutes of meetings with NRA and SSTC.

Achievements (With reference to the TORs)

The project tasks are described in the following:

Assistance to NRA in the phase of the SIP development: the different versions of the SIP report prepared by the industrial side were commented. This work, performed from March to May 1997, was concluded by the signature from NRA of the protocol of agreement of the SIP report on 15 May 1997, according to the schedule of the industrial side. The many Riskaudit comments, discussed in Kiev during technical meetings in March and April 1997, have been included in a common document prepared by NRA for the industrial side on the basis of SSTC and Riskaudit comments. The minutes of the meetings and the different comments on the SIP report represent deliverables of this project.

Assistance to NRA for the approval procedure to the technical specifications of the early biddable projects: the draft of the technical specifications for tenders of the early biddable project was sent by the industrial side to NRA by the middle of August 1997. Riskaudit and SSTC discussed their comments during technical meetings in September 1997. The drafts of the technical specifications were approved by NRA and the comments were annexed to the protocol signed on 11 September 1997 in Kiev, according to the schedule of the industrial side. The minutes of the meetings and the comments on the technical specifications are part of the deliverables of this project.

Assistance to NRA in the field of definition of safe objectives statement of policy: this task is the follow up of the "tentative definition of the safety objectives" completed in August 1996. The SSTC prepared a draft of "Statement of policy", which describes the general safety objectives for the "object shelter". This draft was based on the two documents "Tentative definition of safety objectives" prepared by Riskaudit and SSTC in 1996. This new draft was extensively discussed and commented by Riskaudit. Various comments were presented mainly during technical meetings in July and September 1997 and in March 1998 in Kiev. The final draft of the document was adopted on 1 September 1997 in Kiev and the final document was formally adopted in May 1998. The minutes of the meetings, many comments on the "statement of policy" and the final version of this document represent part of the deliverables of this project.

Assistance to NRA during the preparation of a licensing plan for the SIP preparation and implementation: This task started in March 1997. A first scheme for a licensing plan was prepared in the framework of the SIP report comments and discussed with NRA and SSTC during the preparation of the SIP report comments from March to May 1997. A draft of the "licensing plan for the SIP implementation" was presented in Kiev during the meeting with SSTC and NRA on 15, 16 and 17 October 1997. The minutes of the meetings, the different proposals and comments for a licensing plan and the last final draft, issued in March 1998, represent part of the deliverables of this project.

Assistance to NRA during the preparation of guidelines for the content of Safe Analyses Reports: this task started in December 1997. The guidelines were prepared on the basis of proposals and comments by Riskaudit, and on the basis of draft prepared by SSTC. This document was discussed during meetings since January 1998 to June 1998. The minutes of these meetings and the final draft of the guidelines represent part of the deliverables of this project.
The main deliverables of the project are summarised below:

• Minutes of the meeting
• Comments on the SIP drafts
• Comments on the technical specifications of the early biddable projects
• Comments on and proposals for the safety objectives (statement about policy)
• Final version of the statement about policy
• Comments on and proposals for a licensing plan for the SIP implementation
• Final draft of the licensing plan
• Comments on the guidelines for the content of safety analysis reports
• Final draft of the guidelines for the content of safety analysis reports

Comments

(Quality of the results, Lesson learnt, Recommendations for follow-up)

The project met the objectives stated in the TORs: also the general time schedule of the SIP development and implementation was maintained.