ML20135H170
| ML20135H170 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 05/14/2020 |
| From: | Dennis Galvin Office of Nuclear Reactor Regulation |
| To: | Gerry Powell South Texas |
| Galvin D | |
| References | |
| EPID L-2020-LLA-0108 | |
| Download: ML20135H170 (6) | |
Text
PUBLIC NOTICE THE U.S. NUCLEAR REGULATORY COMMISSION PROPOSES TO AMEND RENEWED FACILITY OPERATING LICENSE FOR THE SOUTH TEXAS PROJECT, UNIT 1 The U.S. Nuclear Regulatory Commission (NRC, the Commission) has received an application dated May 13, 2020 (available in the NRCs Agencywide Documents Access and Management System (ADAMS) at Accession No. ML20134K758), from STP Nuclear Operating Company (STPNOC, the licensee) for an exigent amendment to the renewed facility operating license for the South Texas Project, Unit 1 (STP Unit 1), located in Matagorda County, Texas.
The licensee requests NRC approval by May 28, 2020.
The proposed exigent amendment would modify Technical Specification 3/4.5.1, Accumulators, to allow Unit 1 to operate with all three safety injection accumulators at reduced minimum pressure.
The licensee requested that the proposed amendment be processed on an exigent basis in accordance with the provisions in Title 10 of the Code of Federal Regulations (10 CFR)
Section 50.91(a)(6). Under 10 CFR 50.91(a)(6)(i), where the Commission finds that exigent circumstances exist, in that a licensee and the Commission must act quickly and that time does not permit the Commission to publish a Federal Register notice allowing 30 days for prior public comment, and it also determines that the amendment involves no significant hazards considerations, the Commission will either (A) issue a Federal Register notice providing notice of an opportunity for hearing and allowing at least 2 weeks from the date of the notice for prior public comment or (B) use local media to provide reasonable notice to the public in the area surrounding a licensees facility of the licensees amendment and of its proposed determination that no significant hazards consideration is involved, consulting with the licensee on the proposed media release and on the geographical area of its coverage. Due to the timing of the
proposed amendment, the NRC is providing this notice in local media pursuant to 10 CFR 50.91(a)(6)(i)(B), and has consulted with the licensee and the NRC regional office on the proposed media release.
The licensee provided the following information to explain the exigency of the proposed amendment. The licensee stated that the emergent condition necessitating this request for exigency was caused by increased valve leakage during startup from Unit 1 refueling outage.
After considering several options to address the condition, STPNOC determined that the safest solution was to isolate Unit 1 Safety Injection Accumulator 1A and then request approval of a technical specification change to reduce the minimum allowed cover gas pressure for the accumulators prior to restoration. Because STP Unit 1 will reach the backstop risk-informed completion time allowed by the technical specifications on May 29, 2020, STPNOC has determined that the need for this license amendment request is exigent. The proposed change is necessary to prevent frequent cycling of safety-related equipment or a reactor shutdown to make repairs, both of which would result in increased risk without a commensurate increase in safety.
As required by 10 CFR 50.91(a), the licensee has provided its analysis of the issue of no significant hazards consideration using the standards in 10 CFR 50.92. Under the NRCs regulations in 10 CFR 50.92, this means that operation of the facility in accordance with the proposed amendment would not (1) involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) involve a significant reduction in a margin of safety. The licensee and the NRC have evaluated the proposed change with regard to the determination of whether or not a significant hazards consideration is involved as described below.
Operation of STP Unit 1 in accordance with the proposed amendment will not involve a significant increase in the probability or consequences of an accident previously evaluated. The proposed change reducing the lower pressure limit for the accumulators does not affect the design basis of the plant - this change will have no significant impact on the capability of the accumulators to perform their design basis function. The overall protection system performance will remain within the bounds of the accident analyses documented in Chapter 15 of the STP Updated Final Safety Analysis Report. The change does not affect other structures, systems and components of the plant or change plant operations, design functions or analysis that verifies design functions. The accumulators are not a precursor to any accident previously evaluated. The change results in an insignificant increase in the consequences of the safety analyses and STP Unit 1 will remain within licensing basis limits. The accumulators will continue to function in a manner consistent with safety analyses assumptions and the plant design basis. There will be no degradation in the performance of, or an increase in the number of challenges to, equipment assumed to function during any postulated accident. Therefore, the proposed change does not result in a significant increase in the probability or consequences of an accident previously evaluated.
The proposed amendment will not create the possibility of a new or different kind of accident from any previously evaluated. The proposed change does not involve a physical alteration to the plant or a change in the methods governing normal plant operation - no new or different type of equipment will be installed. The proposed change does not adversely affect the design function or operation of any structures, systems, or components important to safety. No new accident scenarios, transient precursors, failure mechanisms, or limiting single failures are introduced because of the proposed change. Safety systems continue to function in the same manner and there is no reliance on additional systems or procedures. The accumulators are passive components that are not accident initiators. Lowering the accumulator pressure would
not create a new or different kind of accident. The malfunction of safety-related equipment, assumed to be operable in the accident analyses, would not result from the proposed change.
No new failure mode has been created and no new equipment performance burdens are imposed. Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.
The proposed amendment will not involve a significant reduction in a margin of safety.
The proposed change affects the margins related to Peak Clad Temperature, Containment Peak Pressure, and Containment Equipment Qualification Peak Pressure. The analysis of these parameters determined that the margins to the design bases and safety limits were slightly reduced, however the design bases and safety limits were not impacted. The performance of the accumulators remains within design basis limits and the accident analyses safety limits. Therefore, the proposed change does not involve a significant reduction in a margin of safety.
Following an initial review of this application, the requested amendment has been evaluated against the standards in 10 CFR 50.92 and the NRC has made a proposed determination that the requested amendment involves no significant hazards considerations.
The proposed change would not significantly increase the probability or consequences of any accident previously considered, nor create the possibility of a new or different kind of accident, nor significantly reduce any margin of safety.
The NRC is seeking public comments on this proposed determination that the amendment involves no significant hazards considerations. The NRC will consider comments received through May 27, 2020. If the proposed determination that the requested amendment involves no significant hazards consideration becomes final, the NRC will issue the amendment without first offering an opportunity for a public hearing. An opportunity for a hearing will be
published in the Federal Register at a later date and any hearing request will not delay the effective date of the amendment.
The NRC may issue the amendment prior to the expiration of the comment period, should circumstances change such that failure to act in a timely way would result, for example, in derating or shutdown of the facility. Should the NRC take action prior to the expiration of the comment period, it will publish in the Federal Register a notice of issuance. Before any issuance of the proposed amendment, the NRC will need to make the findings required by the Atomic Energy Act of 1954, as amended, and NRC regulations.
If the NRC decides in its final determination that the amendment does involve a significant hazards consideration, a notice of opportunity for a prior hearing will be published in the Federal Register and, if a hearing is granted, it will be held before the amendment is issued.
Comments on the proposed determination of no significant hazards consideration may be (1) telephoned to Thomas Wengert, Acting Branch Chief, Plant Licensing Branch 4, or Dennis Galvin, Project Manager, Plant Licensing Branch 4, by collect call to 301-415-4037 or 301-415-6256, respectively, (2) e-mailed to Thomas.Wengert@nrc.gov or Dennis.Galvin@nrc.gov, or (3) submitted in writing to Office of Administration, Mail Stop:
TWFN-7-A60M, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, ATTN: Program Management, Announcements and Editing Staff. All comments received by close of business, 4:15 pm EDT, on May 27, 2020, will be considered in reaching a final determination.
A copy of the application may be examined electronically through the NRCs ADAMS in the NRC Library at https://www.nrc.gov/reading-rm/adams.html under Accession No. ML20134K758. Persons who do not have access to ADAMS or who encounter problems in accessing the documents located in ADAMS should contact the NRC Public Document Room
Reference staff by telephone at 1-800-397-4209, or 301-415-4737, or by e-mail to pdr.resource@nrc.gov.