ML19228A165
| ML19228A165 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 08/26/2019 |
| From: | Klos L Plant Licensing Branch IV |
| To: | Sawatzke B Energy Northwest |
| Klos L, 301-415-5136 | |
| References | |
| EPID L-2019-LLA-0174 | |
| Download: ML19228A165 (5) | |
Text
ENCLOSURE PUBLIC NOTICE PUBLIC NOTICE NRC STAFF PROPOSES TO AMEND OPERATING LICENSE AT THE COLUMBIA GENERATING STATION The U.S. Nuclear Regulatory Commission (NRC) staff has received an application dated August 15, 2019, (available at Agencywide Documents Access and Management System (ADAMS) Accession No. ML19227A370) from Energy Northwest, for an exigent amendment to the operating license for the Columbia Generating Station (Columbia), located in Richland Washington.
The license amendment would change Technical Specification (TS) 3.8.7.As, Electrical Power Systems, Distribution Systems - Operating, (available at Agencywide Documents Access and Management System (ADAMS) Accession No. ML0531A30319), Completion time (CT), on a one-time basis from 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This amendment would support replacement of Columbias Phase A transformer within the new one-time CT period and not require entry into Mode 3, hot shutdown, for the operating plant. On August 2, 2019, the current Phase A transformer was classified as degraded but operating within administrative limits supplying voltage to the downstream electrical distribution bus.
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)
2 Section 50.91(a)(6). Under 10 CFR 50.91(a)(6)(i)(B), 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 use local media to provide reasonable notice to the public in the area surrounding a licensee's facility of the licensee's 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.
The licensees claim of exigent circumstances is based on the considerations below. On August 2, 2019, the current Phase A transformer was classified as degraded. Previous repair history and experience identifies that 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is an insufficient period for a replacement of this transformer which would then exceed the current allowed TS completion time. Additionally, this one-time change in completion time for transformer repair would allow a replacement of the plants transformer at the earliest scheduled opportunity while, as described below, not involve a significant increase in the probability or consequence of an accident previously evaluated.
The licensee and the NRC staff have evaluated this proposed change with regard to the determination of whether or not a significant hazards consideration is involved. Operation of Columbia, in accordance with the proposed amendments will not involve a significant increase in the probability or consequences of an accident previously evaluated.
The proposed amendment does not increase the probability of an accident because the onsite Class 1E Alternating Current (AC) electrical power distribution cannot initiate an accident.
The onsite Class 1E AC electrical power distribution system ensures the availability of AC electrical power for the systems required to shut down the reactor and maintain it in a safe condition after an anticipated operational occurrence or a postulated design basis accident. The proposed one time 24-hour CT extension does not alter the conditions, operating configurations, or minimum amount of operating equipment assumed in the safety analysis for accident
3 mitigation. No changes are proposed in the manner in which the electrical power distribution provides plant protection or which create new modes of plant operation. In addition, a plant evaluation concluded that the risk contribution of the increased CT is a very small increase in risk. The proposed change in CT will not affect the probability of any event initiators. There will be no degradation in the performance of, or an increase in the number of challenges imposed on, safety related equipment assumed to function during an accident situation. There will be no change to normal plant operating parameters or accident mitigation performance. Therefore, the proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated.
The proposed amendments will not create the possibility of a new or different kind of accident from any previously analyzed. The proposed amendment will not create the possibility of a new or different kind of accident because inoperability of Division 1 AC electrical power distribution is not an accident precursor. There are no hardware changes nor are there any changes in the method by which any plant system performs a safety function. This request does not affect the normal method of plant operation. The proposed amendment does not introduce new equipment, or new way of operation of the system which could create a new or different kind of accident. No new external threats, release pathways, or equipment failure modes are created. No new accident scenarios, transient precursors, failure mechanisms, or limiting single failures are introduced as a result of this request. Therefore, the implementation of the proposed amendment will not create a possibility for an accident of a new or different type than those previously evaluated.
The proposed amendment will not involve a significant reduction in a margin of safety.
Columbias AC and Direct Current (DC) electrical power distribution subsystems are designed with sufficient redundancy such that one division may be removed from service for maintenance or testing and the remaining subsystems are capable of providing electrical loads to satisfy the Final Safety Analysis Report requirements for accident mitigation or plant shutdown. A plant
4 evaluation concluded that the risk contribution of the CT extension is within allowable limits.
There will be no change to the way safety limits or limiting safety system settings are determined nor will there be any change to those plant systems necessary to assure the accomplishment of protection functions. For these reasons, the proposed amendment does not involve a significant reduction in a margin of safety.
Following an initial review of this application, the requested amendments have been evaluated against the standards in 10 CFR 50.92 and the NRC staff has made a proposed (preliminary) determination that the requested amendments involve no significant hazards considerations. The changes do not significantly increase the probability or consequences of any accident previously considered, nor create the possibility of an accident of a different kind, nor significantly decrease any margin of safety.
If the proposed determination that the requested license amendment involves no significant hazards consideration becomes final, the staff will issue the amendments 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.
If the staff 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 Bob Pascarelli, Chief, Plant Licensing Branch IV, by collect call to 301-415-6603, or by facsimile to 301-415-2102, (2) e-mailed to Bob.Pascarelli@nrc.gov, or (3) submitted in writing to the May Ma, Office of Administration, Mail Stop: OWFN-2-A13, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001. All comments received by close of business on August 23, 2019 from 7:30 a.m. to 4:15 p.m. Federal workdays will be considered in reaching a final determination. A copy of the application may be examined electronically
5 through the NRCs Agencywide Documents Access and Management System (ADAMS) in the NRC Library at http://www.nrc.gov/reading-rm/adams.html and at the Commission's Public Document Room (PDR), located at One White Flint North, Public File Area O1 F21, 11555 Rockville Pike (first floor), Rockville, Maryland. Persons who do not have access to ADAMS or who encounter problems in accessing the documents located in ADAMS should contact the NRC PDR Reference staff by telephone at 1-800-397-4209, or 301-415-4737, or by e-mail to pdr.resource@nrc.gov.