U3.IA/03-3 Development of regulatory documents and inspection procedures for commissioning of new nuclear installations (ref AP 7.2.3.1)

UK/TS/32 was a technical support project including 2+2 tasks, for support to the nuclear safety regulator of Ukraine (SNRCU). It included 11 technical tasks mainly related to remaining modernisation steps of Khmelnitsky 2 and Rovno 4 (K2R4).

Task 1, Review of Inspection Procedures for Commissioning of New Nuclear Installations

EU experts gave regulatory and technical advices to SNRCU based on the practice in European countries on the development of new regulatory documents concerning inspection procedures for commissioning of new nuclear installations:

• Procedure for State Supervision on Observation of Nuclear and Radiation Safety,
• Requirements in Nuclear Energy Use,
• Conditions and the Procedure for issuing specific written permits to carry out certain types of activity and operations at the stages of commissioning, operation and decommissioning of a nuclear installation,
• The draft document "Procedure for nuclear power plant commissioning" taking into account the IAEA Safety Guide NS-G-2.9 is under completion
• Detailed technological specifications of guidance documents, e.g. some guidance documents for the Object Shelter (Tsjernobyl) in terms of their possible future modification for other nuclear facilities.

The regulations were submitted by the SNRCU for registration in Ukrainian Department of Justice, after which they will enter into force.

Task 2 Assistance to SNRCU in Licensing of the industrial projects (U1.01/04 and U1.03/04D) Solid Radwaste Treatment on Rovno and Zaporozhe NPPs

EU experts reviewed the Technical Specifications for the tender (different lots of installations to be supplied) including a walk down at the Solid Waste Treatment and Storage Facility (SWTSF).

The task concerned the Solid Waste Treatment and Storage Facility (SWTSF) for Zaporozhye NPP (3 processing facilities), the Technical Specifications for the tendering of the Solid Radwaste Treatment Facility (SRWTF) on both NPPs, and the Technical Specifications for the Project U1.03/06A1 “Radwaste Treatment Facilities”,

Most comments of EU experts and SSTC experts were considered in the improved revisions of the Technical Specifications.

Task 3 Measure 11011 “Develop materials on equipment qualification”

The experts found that ageing effects were not mentioned for environmental and seismic qualification and they recommended to SNRCU to issue a regulatory safety guide on regulatory requirements for EQ considering the key aspects related to phases, methods, grouping, ageing, sampling, margins.

Task 4 Measure 12111 “To implement measures on primary circuit protection against overpressure in cool-down mode through technical inspection of ECCS and primary circuit against overpressure in cold state”

Based on the reviews of the EU and SSTC experts it was concluded that the valves “PRZ PORV VS66/99” (Pressurizer Pilot Operated Relief Valve) are suitable for this application.

Task 5 Measure 12411 “Develop accident management measures for the accident – primary to secondary leak with equivalent diameter of 100 mm”

Two documents concerning the justification of the selected accident management strategy and the corresponding part of Preliminary Safety Assessment Report (PSAR) were reviewed and crucial comments and recommendations were put forward by EU experts. The Ukrainian utility was requested to develop a new schedule of revised files submission.

Task 6 - Measure 13411 “Use of PZR PORV for forced pressure suppression in primary circuit, for implementation of “Feed and Bleed” procedure on primary circuit”

SSTC and EU experts evaluated documents concerning the use of PZR PORV for forced pressure suppression in primary circuit, for implementation of a “Feed and Bleed” procedure on the primary circuit. The experts concluded that the lack of information and data in the assessed documents did not allow a final judgment on the efficiency and reliability. It was recommended that SNRCU requests the Ukrainian utility to update the measure files on the basis of the comments from EU and SSTC experts.

Task 7 Measure 16211 “Install hydrogen detection and combustion system in reactor containment premises"

Documents including the “Factory Acceptance Testing Programme” and “Technical specification for supply" for the Installation of hydrogen detection and combustion systems inside of reactor containment premises (modernization measure 16211) were reviewed.

SNRCU stated that the EU recommendations were useful for the further licensing process (PSAR updating) and that SNRCU has required Energoatom to verify hydrogen production in Beyond Design Based Accident (BDBA) situations.

Task 8 Measure 17321 “Perform special analysis to determine extent of pipeline breaks and probability of secondary impacts consequences”

The conclusion was that the Superpipe concept was not applied correctly and could not be applied, other measures compensated for this. Riskaudit experts proposed further actions for the substantiation of the safety case. Further review activities of this issue are carried out within the project UK/TS/34.

Task 9 “Enhance the function of the existing radiation protection” Measure 33211

This task was cancelled on request of SNRCU

Task 10 “Overall conclusion of the 147 measures of K2/R4 implementation”

Documents concerning the Modernization Program for Kh2/R4 safety upgrading were reviewed and four inspection visits on NPP site during the outages were performed. It could be concluded that the safety deficiencies of the initial design WWER-1000 type V-320, marked in the different USSR, Russian, Ukrainian, IAEA reports and documents, are eliminated or compensated. The Design safety level of the power unit 2 of Khmelnitsky NPP and power unit 4 of Rivne NPP now could be evaluated as not less then one for the NPPs power units of the same generation in the European countries.

Task 11 “Assessment of the modernization program for operating Ukrainian NPPs”

The safety level of all Ukrainian NPP’s taking into account the different modernisation measures already implemented and the on-going modernisation programs was assessed. Practically the technical assistance consisted in evaluation of the various revisions of the “Joint Safety Improvement Program –SPB” (SPB from the Ukrainian abbreviation for JSIP) developed by the utility. EU experts comments and remarks were transmitted to SNRCU and that SNRCU ensured that they will be taken into account by the utility to upgrade the further revision of the Joint Safety Improvement Program.

From the point of view of EU experts, the implementation of the SPB program will bring the Ukrainian NPPs in compliance with the internationally recognized safety level for NPP units of the same vintage.