Japan Nuclear Fuel Limited
Change in Schedule for Completion of Rokkasho Reprocessing Plant
Japan Nuclear Fuel Limited (JNFL) had tackled toward the completion of Rokkasho Reprocessing Plant (RRP) in the first half of FY2022 while the conformity review for Design and Construction Plans and construction works to enhance safety complying with new regulatory requirements continued. However, JNFL decided the reconsideration of the completion date of RRP and reported to the Aomori prefecture and Rokkasho village on September 7, 2022.
The governor of Aomori prefecture requested JNFL to show "cause analysis of the delay in the conformity review and countermeasures" and "way to the completion of RRP."
JNFL formulates "cause analysis of the delay in the conformity review" and "way to the completion of RRP" and sets the completion date of RRP as "the earliest possible time in the first half of FY2024" based on a comprehensive judgement, considering the three elements—construction works, conformity review for Design and Construction Plans and inspections.
The approval of the first part of Design and Construction Plans by the Nuclear Regulation Authority (NRA) on December 21 was a big step toward the completion. JNFL applied for the approval of the second part of Design and Construction Plans on December 26. JNFL recognizes that RRP is in the final stage toward the completion.
JNFL tackles to achieve the earlier completion together with all the Japanese relevant entities with top priority on safety.
1. Cause analysis of the delay in the conformity review and countermeasures
JNFL analyzed the cause of the delay in the review for the approval of the first part of Design and Construction Plans (the first part conformity review). JNFL takes countermeasures to steadily advance the conformity review for the approval of the second part of Design and Construction Plans (the second part conformity review).
(1) Cause analysis
- JNFL lacked the understanding of the matters indicated by the NRA due to insufficient communication with the NRA. And information sharing and collaboration among sections involved were insufficient.
- JNFL was not able to judge that the modifications of already approved contents and initial design of Design and Construction Plans were necessary. Deeper understanding about the part of regulatory requirement and more detailed technical and multidimensional check were required.
(2) Countermeasures and endeavor
- Supporters from electric power companies who experienced their conformity review joined JNFL for the approval of Design and Construction Plans, participated in the hearings and meetings with the NRA in order to share the view on explanation policy and categorization, and got involved in the preparation of documents by relevant sections and supported them, which resolved the lack of collaboration among sections involved.
- A system in which internal and external supporters who experienced the conformity review become the core has been established to check conformity to regulatory requirements from their technical and multidimensional review.
(3) Status of improvement by the countermeasures and endeavor by JNFL
- JNFL shared the common view for the second part conformity review through the meetings and others with the NRA.
- The reinforcement of the system and the improvement of lack of collaboration among related sections created the common view among all persons concerned on way of explanation and categorization of equipment. Documents of application including approximately 25 thousand equipment were submitted for the second part conformity review.
- JNFL arranges systematically all the equipment based on each article of rules on technical standards, and proceeds with the second part review efficiently with continued communication with the NRA and close information sharing and collaboration among sections involved.
2. Way to the completion of RRP
JNFL considered the three elements—construction works, conformity review for the approval of Design and Construction Plans and inspections—to show the new completion date.
(1) Construction works
- Main construction works have been almost completed in 2022.
- Works to connect new equipment to existing equipment and inspections (connection works, etc.) will be carried out by the completion after the approval of Design and Construction Plans by the NRA.
(2) Conformity review for Design and Construction Plans
- The first part of Design and Construction Plans was approved on December 21, 2022. JNFL submitted the second part which covers all the remaining equipment on December 26, 2022.
- JNFL will explain representative equipment at the second part conformity review after the equipment categorization based on the explanatory policy presented at the conformity review on December 20, 2022. JNFL will divide the explanation into three—"Ground and earthquake resistance," "Design basis equipment" and "Severe accidents measures equipment"—and explain them in parallel.
- "Ground and earthquake resistance" is a dominant factor which decides the review period. Concerning the "ground," JNFL will explain the ground models which reflect its site characteristics. Concerning the "earthquake resistance," JNFL will explain this by using the categorization.
- Regarding the “Design basis equipment,” the design policy was almost discussed at the first part conformity review. "Severe accidents measures equipment" were almost explained during the review of Amendment of Business Permit for Reprocessing Facility. Based on these, JNFL will explain efficiently to the NRA.
- Based on these, JNFL has set the review period as approximately 1 year.
(3) Inspections
- There are licensee's pre-service inspection and pre-service confirmation.
- JNFL decided the period necessary for the inspections carried out after the approval of Design and Construction Plans, considering the licensee's pre-service inspection and pre-service confirmation of the connection works, inspection of vitrification melters and works to switch the route of sea release system. JNFL also considered the possibility of pre-service confirmation period longer than expected and decided to set a longer inspection period.
- Licensee's pre-service inspection of connection works, etc. will be conducted in parallel with these works.
- Based on these, JNFL has set the inspection period after the approval of Design and Construction Plans as approximately 4 to 7 months.
(4) Completion date
As a result of the comprehensive judgement of the above three elements, the conformity review for Design and Construction Plans will take approximately 1 year, and the inspection period after the approval will be 4 to 7 months. Therefore, JNFL has set the completion date of RRP as "the earliest possible time in the first half of FY2024." JNFL tackles to achieve the earlier completion together with all the Japanese relevant entities with top priority on safety.