ML20078N547
| ML20078N547 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 12/02/1994 |
| From: | Hebdon F Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20078N550 | List: |
| References | |
| NUDOCS 9412070035 | |
| Download: ML20078N547 (6) | |
Text
I i
?;
l UNITED STATES NUCLEAR REGULATORY COMMISSION TENNESSEE VALLEY AUTHORITY l
i SE000YAH NUCLEAR PLANT. UNIT 1 DOCKET NO. 50-327 ENVIRONMENTAL ASSESSMENT AND FINDING 0F NO SIGNIFICANT IMPACT The U.S. Nuclear Regulatory Commission (the Commission) is considering issuance of an exemption from the requirements of Section III.D.3 of Appendix J to 10 CFR Part 50 to the Tennessee Valley Authority, licensee for the Sequoyah Nuclear Plant (SQN), Unit 1.
The plant is located at the licensee's site in Hamilton County, Tennessee.
ENVIRONMENTAL ASSESSMENT Identification of Proposed Action:
The proposed action would exempt the licensee from the provisions in Section III.D.3 of Appendix J to 10 CFR Part 50 with respect to the requirement to perform Primary Containment Type C local leak rate tests (LLRTs) at intervals no greater than 2 years.
The exemption would affect Unit 1 only and allow certain Type C valve penetration LLRTs that are specified in the submittal (126 valves out of a total of 242 valves subject to the LLRT program) to be delayed until the Cycle 7 refueling outage.
This outage is scheduled to start approximately 5 months after the expiration date of the earliest Type C test.
i 1
9412070035 941202 PDR ADOCK 05000327 P
On March 2, 1993, SQN Unit 1 entered a forced nutage and started the Cycle 6 refueling outage. All Type B and Type C LLRTs were performed during the outage, which ended in December 1993. The unit returned to service on April 20, 1994. Due to the length of the outage, a number of LLRTs that were performed early in the outage were retested prior to conducting the containment integrated leak rate test (CILRT) in December 1993.
LLRTs of valves that were initially tested between April 3 and July 19, 1993, however, were not retested because of schedule restraints associated with the CILRT.
Since the 2 year time interval for the Type C valve penetrations that were not retested will expire starting in April 1995, Unit I would be forced to shut down at that time to perform the tests unless a schedular exemption is granted.
The next Unit I refueling outage is scheduled to start in September 1995. Therefore, the licensee has proposed an exemption to allow a one-time deferment of the Appendix J interval requirement for the affected Type C valve penetration tests from April 3, 1995, until October 1, 1995, a total of approximately 181 days from the first valve tested during the Cycle 6 outage.
The proposed action is in accordance with the licensee's application for exemption dated November 10, 1994.
The Need for the Proposed Action:
The proposed action is required to exempt the licensee from the requirement to conduct certain specified Type C containment local leak rate tests.on SQN Unit I at a 2-year frequency so the tests can be performed during the Cycle 7 refueling outage scheduled to start in September 1995.
However, TVA has requested extension of the time interval to October 1, 1995, to account for unforeseen circumstances.
e
. Environmental Imoacts of the Proposed Action:
With respect to the requested action, exemption from the above requirement would allow the licensee to delay conducting certain Type C local leak rate tests at Unit I approximately 181 days beyond the scheduled expiration date of the 2-year period for the first LLRT performed during the Cycle 6 outage. This relatively small increase in the test interval does not significantly contribute to the total leakage limits. The intent of Section III.D.3 of Appendix J is to ensure that containment leakage is maintained within the prescribed limits.
Based on the following information, the exemption will not significantly affect the ability of the d
individual primary containment valves that are subject to the Type C tests to perform this safety function:
1.
The valves for which the extension of the 2-year interval is being requested have a history of being leak tight and in good condition. The leak-tight condition of these components was last verified by Type C LLRTs
)
and by the Type A test conducted in December 1993.
Based on the preserit containment leak rate that accounts for less than 93 percent of the 0.75 La limit, the remaining margin is sufficient to ensure any incremental increase in leakage resulting from the extension would not cause unacceptable as-found test results.
2.
Based on historical data, any incremental increase in leakage because of the extension will be small.
Improved maintenance practices implemented during the Unit 1 Cycle 5 outage and continued into the Cycle 6 outage, including motor operated valve testing (M0 VATS) of containment isolation valves, provide increased assurance that these components will perform their safety function.
J
_4_
3.
The valves for which the exemption is requested were included in the Type A test performed in December 1993. This test indicated a containment leak rate of 0.1742 percent per day, which is below the 0.1875 percent per
-day limit.
The change will not increase the probability or consequences of accidents, no changes are being made in the types of any effluents that may be released offsite, and there is no significant increase in the allowable individual or cumulative occupational radiation exposure. Accordingly, the Commission concludes that there are no significant radiological environmental impacts associated with the proposed action.
~
With' regard to potential nonradiological environmental impacts, the proposed action does involve features located entirely within the restricted area as defined in 10 CFR Part 20.
It does not affect nonradiological plant effluents and has no other environmental impacts.
Accordingly, the Commission concludes that there are no significant nonradiological impacts associated with the proposed action.
Alternatives to the Proposed Action:
Since the Commission has concluded that there is no measurable environmental impact associated with the proposed exemption, any alternatives with equal or greater environmental impact need not_ be evaluated. The principal alternative would be to deny the request.
Such action would not enhance the protection of the environment and would result j
in unjustified cost to the licensee.
1 1
l k
g, --
3 F
5,. -
'a Alternative Use of Resources:
1 This action does not involve the use of resources not previously considered'in the " Final Environmental Statement Related to the Operation j
of the Sequoyah Nuclear Plant, Units 1 and 2," dated February 21, 1974.
f Aaencies and Persons Consulted
- The NRC staff-consulted with the Tennessee State official regarding the environmental impact of the proposed action. The State official had no i
comments.
FINDING 0F NO SIGNIFICANT IMPACT:
Based on the environmental assessment, the Commission concludes that i
the proposed action will not have a significant effect on the quality of the human environment. Accordingly, the Commission has determined not to prepare an environmental impact statement for the proposed action.
For further details with respect to the proposed action, see the licensee's letter dated November 10, 1994, which is available for public inspection at the Commission's Public Document Room, The Gelman Building, 2120 L Street, NW., Washington, DC, and at the local public document room l
located at the Chattanooga-Hamilton County Library, 1101 Broad Street, Chattanooga, Tennessee 37402.
Dated at Rockville, Maryland, this 2nd day of December 1994.
FOR THE NUCLEAR REGULATORY COMMISSION f
FrederickJ.Hekon, Director Project Directorate II Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation 1
c--
c Mr. Oliver D. Kingsley, Jr.
SEQUOYAH NUCLEAR PLANT Tennessee Valley Authority cc:
Mr.
0.~ J. Zeringue, Sr. Vice President TVA Representative Nuclear Operations Tennessee Valley-Authority Tennessee Valley Authority 11921 Rockville Pike 3B Lookout Place Suite 402 1101 Market Street Rockville, MD 20852 Chattanooga, TN 37402-2801 Regional Administrator Dr. Mark 0. Medford, Vice President U.S. Nuclear Regulatory Commission Engineering & Techt.ical Services
. Region II Tennessee Valley Authority 101 Marietta Street, NW., Suite 2900 3B Lookout Place Atlanta, GA 30323 1101 Market Street Chattanooga, TN 37402-2801 Mr. William E. Holland Senior Resident Inspector Mr. D. E. Nunn, Vice President Sequoyah Nuclear Plant New Plant Completion U.S. Nuclear Regulatory Commission Tennessee Valley Authority 2600 Igou. Ferry Road 3B Lookout Place Soddy Daisy, TN 37379 1101 Market Street Chattanooga, TN 37402-2801 Mr. Michael H. Mobley, Director
(
Division of Radiological Health l
Site Vice President 3rd Floor, L and C Annex Sequoyah Nuclear Plant 401 Church Street t
Tennessee Valley Authority Nashville, TN 37243-1532 P.O. Box 2000 Soddy Daisy, TN 37379 County Judge Hamilton County Courthouse General Counsel Chattanooga, TN 37402 Tennessee Valley Authority
~
ET 11H 400 West Summit Hill Drive Knoxville, TN 37902 Mr. P. P. Carier, Manager Corporate Licensing Tennessee Valley Authority 4G Blue Ridge
~
1101 Market Street Chattanooga, TN 37402-2801 Mr. Ralph H. Shell Site Licensing Manager Sequoyah Nuclear Plant i
Tennessee Valley Authority P.O. Box 2000 Soddy Daisy, TN 37379
.