ML19183A272
| ML19183A272 | |
| Person / Time | |
|---|---|
| Site: | 07201015 |
| Issue date: | 07/02/2019 |
| From: | John Mckirgan Spent Fuel Licensing Branch |
| To: | Fowler W NAC International |
| White B | |
| Shared Package | |
| ML19183A268 | List: |
| References | |
| EPID L-2018-LLA-0254 | |
| Download: ML19183A272 (2) | |
Text
FINAL SAFETY EVALUATION REPORT NAC INTERNATIONAL NAC-UMS STORAGE SYSTEM DOCKET NO. 72-1015 AMENDMENT NO. 7 Summary This safety evaluation report (SER) documents the U.S. Nuclear Regulatory Commission (NRC) staffs review and evaluation of an amendment to Certificate of Compliance No. 1015 for the Model No. NAC-UMS spent fuel storage system. On September 18, 2018 (Agencywide Documents Access and Management System Accession No. ML18264A014), NAC International (NAC or the applicant) submitted a request to the NRC in accordance with Title 10 of the Code of Federal Regulations (10 CFR) 72.244 to amend Certificate of Compliance No. 1015.
NAC requested the NRC revise the basis for Technical Specification A3.1.6 to clarify that the surveillance requirements for Technical Specification A3.1.6 require a minimum of two outlet air temperature measurements to provide an average outlet temperature.
In support of the amendment, NAC submitted Revision 18A of the safety analysis report (SAR) for the NAC-UMS storage system. The NRC staff reviewed the amendment request using guidance in NUREG-1536, Standard Review Plan for Dry Cask Storage Systems, Rev. 1, dated July 2010. For the reasons stated below, and based on its review of the statements and representations in the application and the conditions specified in the Certificate of Compliance and Technical Specifications, the staff concludes that the requested changes meet the requirements of 10 CFR Part 72.
The NRC staff determined that the following areas of review are not affected by this amendment and therefore are not addressed in this SER: general information principle design criteria, structural, confinement, shielding, criticality, materials, operating procedures, acceptance tests and maintenance program, radiation protection, accident analyses, and quality assurance. The only change to the Technical Specifications is discussed in the thermal evaluation below.
4.0 Thermal Evaluation Currently, the SAR does not specify how many outlet air temperature measurements must be taken to determine the average outlet temperature. The applicant proposed revising the SAR to clarify that temperature readings must be taken from at least two outlet vents. The staff reviewed and evaluated the proposed change and finds it acceptable because it is consistent with NUREG-1536, Revision 1 Standard Review Plan for Spent Fuel Dry Storage Systems at a General License Facility.
In addition to the SAR change, the staff amended the surveillance requirements for Technical Specifications A3.1.6.1 and A3.1.6.2 to ensure adequate monitoring of the concrete cask heat removal system is performed such that the temperature of any material that is important to safety remains below its allowable limit during normal operation. As it stands, the surveillance requirements for Technical Specifications A3.1.6.1 and A3.1.6.2 do not specify at which outlet Enclosure 4
vents the measurements must be taken. The staff revised the relevant surveillance requirements to state:
Verify the difference between the ISFSI ambient temperature and the average outlet air temperature of at least two outlet vents (at least two vents must be located 180° apart from each other) is 102ºF for the PWR [pressurized-water reactor] canister or 92ºF for the BWR [boiling-water reactor] canister.
This revised language will provide assurance that a realistic average outlet air temperature is measured. This realistic measurement will give an indication of any blockage at the inlet vents when the surveillance requirements are applied.
The staff finds that the thermal design of Certificate of Compliance No. 1015 remains in compliance with 10 CFR Part 72 and that the applicable design and acceptance criteria have been satisfied.
4.1 Evaluation Findings
F4.1 The staff reviewed the application and concludes that the proposed changes to the Technical Specifications are in compliance with 10 CFR Part 72 and that the applicable design and acceptance criteria have been satisfied. The NRC staff evaluation of the Technical Specification changes provides reasonable assurance that the NAC-UMS will continue to provide safe storage of spent nuclear fuel. This conclusion is reached on the basis of a review that considered the regulation itself, appropriate regulatory guides, applicable codes and standards, and accepted engineering practices.
CONCLUSION The staff performed a detailed safety evaluation of the application for Amendment No. 7 to Certificate of Compliance No. 1015 for the NAC-UMS storage system. The staff performed the review in accordance with the guidance in NUREG-1536. Based on the statements and representations contained in the application and the conditions established in the certificate of compliance and its Technical Specifications, the staff concludes that these changes do not affect the ability of the NAC-UMS storage system to meet the requirements of 10 CFR Part 72.
Issued with Certificate of Compliance No. 1015, Amendment No. 7, on 7/2/19