ML20248B628
| ML20248B628 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 09/22/1989 |
| From: | Black S Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20248B634 | List: |
| References | |
| NUDOCS 8910030252 | |
| Download: ML20248B628 (6) | |
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7590-01 UNITED STATES NUCLEAR REGULATORY COMMISSION TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT, UNIT 1 DOCKET NO. 50-327 ENVIRONMENTAL ASSESSMENT AND FINDING OF NO SIGNIFICANT IMPACT The U. S. Nuclear Regulatory Comission (the Comission) is considering issuance of two exemptions, one temporary and one permanent, from the require-ments of Section III.D.1(a) of Appendix J to 10 CFR Part 50 to the Tennessee Valley Authority (the licensee) for the Sequoyah Nuclear Plant, Unit 1.
The unit is located at the licensee's site in Hamilton County, Tennessee.
The temporary and permanent exemptions were requested by the licensee in its letters dated May 1 and 5, 1989, respectively.
ENVIRONMENTAL ASSESSMENT Identification of Proposed Action: lhe temporary and permanent exemptions would allow the licensee relief from the provisions of Section III.D.1(a) of Appendix J that require that (1) the set of three Type A, or containment inte-grated leak rate, tests shall be performed at approximately equal intervals during each 10-year service period and (2) the third test of each set shall be conducted when the unit is shutdown for the 10-year unit inservice inspection i
(ISI).
In the two requests, the licensee has requected temporary and permanent 8910030252 890922 PDR ADOCK 05000327 P
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exemptions for Unit 1 to (1) conduct the third test of the first 10-year service period during the Unit 1 Cycle 4 refueling outage and (2) separate the third test of each 10-year service period from the 10-year ISI. The first request is for a temporary exemption for only the upcoming test so that it may be conducted during the Unit 1 Cycle 4 refueling outage instead of during a special outage to conduct the test. The second request is for a pemanent exemption so that the third test of each 10-year service period and the 10-year ISI can be scheduled separately.
For the temporary exemption Appendix J to 10 CFR Part 50 requires that a set of three tests shall be performed at approximately equal intervals during each 10-year service period.
The NRC staff has determined that the
" approximately equal interval" is a0 10 months.
The licensee is requesting a temporary exemption to allow the third test for Unit 1 in its first 10-year service period to be conducted at an interval greater than 50 months from the second test.
The additional interval while the unit is operating until it shuts down for its Cycle 4 refueling outage is no more than three months.
The measured overall leak rate for the first test for Unit I was 0.09429 percent per day. Unit 1 entered its Cycle 3 refueling outage on August 22 f
1985, and the second test of the fir::t 10-year service period was conducted on
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December 15, 1985.
The measured overall leak rate for the second test was 0.05388 percent per day. Both the first test and the second test were signifi-cantly less than the maximum allowable leak rate of 0.25 percent per day for i
Unit 1.
Unit I was in an extended shutdown from August 22, 1985 until its restart in November 1988.
In this shutdown, TVA stated that no modifications were made
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3 on the containment boundary.
In addition, the local leak tests on all penetra-tion and valves requiring Appendix J Type B and Type C testing were acceptably completed. The surfaces of the containment liner and shield building were.
l inspected for abnormal degradation before the restart of Unit I and none was observed. The leak rate for the test in December 1985 should not degrade beyond the maximum allowed leak rate in the not more than three months of addi-tional plant operation beyond the 50 months allowed, before the shut down of Unit I to conduct the third test.
f For the permanent-exemption Appendix J to 10 CFR Part 50 requires that the third test of each 10-year service period shall be conducted when the unit is shut down for the 10-year ISI. The licensee is requesting an exemption.to permanently decouple the third test from the 10-year ISI. The third test for l
Unit 1 for the first 10-year service period is scheduled for the Unit 1 Cycle 4 refueling outage for the unit.
The 10-year ISI is not related to the integrity of the containment pressure boundary and is currently scheduled in accordance with Section XI of the American Society of Mechanical Engineers (ASME) Code and with 10 CFR 50.55a(g)(4) for 1994. The first 10-year ISI for Unit 1 is, therefore, scheduled for a future refueling outage other than the Unit 1 Cycle 4 refueling outage.
Each future 10-year ISI will, therefore, be scheduled for a different outaga than the outage for the third test of any 10-year service period.
The Need for the Proposed Action:
The proposed temporary and pemanent exemp-tions are requir ' to permit the licensee to (1) conduct the third test for Unit I during a scheduled Unit I refueling outage instead of during a forced l
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outage and (2) uncouple the third test during a 10-year service period from the 10-year ISI.
Environmental Impacts of the Proposed Action: With respect to the requested temporary and pemanent exemptions, the relief from the above requirements of Appendix A would permit the licensee to conduct the third test in the Unit 1 Cycle 4 refueling outage. With regard to potential radiological environmental impacts, the proposed temporary and permanent exemptions would not allow the licensee to operate Unit I longer than allowed by the. operating license for the unit. Neither the probability of accidents nor the radiological releases from accidents will be increased.
The proposed temporary and permanent exemptions do not increase the radiological effluents from the facility and do not increase the occupational exposure at the facility. Therefore, the Commission concludes that there are no significant radiological impacts associated with the proposed temporary and permanent exemptions.
With regard to potential nonradiological environmental impacts, the pro-posed temporary and permanent exemptions involve systems located within the restricted areas as defined in 10 CFR Part 20. They do not affect nonradio-logical plant affluents and have no other environmental impact. Therefore, the Comission concludes that there are no significant nonradiological environ-mental impacts associated with the proposed temporary and permanent exemptions.
Therefore, the proposed temporary and pemanerit exemptions do not signi-ficantly change the conclusions in the licensee's " Final Environmental State-ment Related to the Operation of Sequoyah Nuclear Plant, Units 1 and 2." (FES) dated February 21. 1974. The Commission concluded that operation of the Sequoyah units will not result in any environmental impacts other than those
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evaluated in the FES in its letter to the licensee dated September 17, 1960 which granted the Facility Operating License DPR-77 for Unit 1.
Alternative to the Proposed Action: Because the staff has concluded that there is no measurable environmental impact associated with the proposed temporary t
and permanent exemptions, any alternative to these exemptions will have either no significantly different environmental impact or greater environmental impact.
I The principal alternative would be to deny the requested temporary and pemanent exemptions. This would not reduce environmental impacts as a result of Unit 1 operations.
Alternative Use of Resources: This action does not involve the use of resources not previously considered in connection with the " Final Environmental
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l Statement Related to the Operation of the Sequoyah Nuclear Plant Units 1 and 2 " dated February 21, 1974.
I Agencies and Persons Consulted:
The NRC staff has reviewed the licensee's requests that support the proposed temporary and permanent exemptions. The NRC j
staff did not consult other agencies or persons.
FINDING OF NO SIGNIFICANT IMPACT The Commission has detemined not to prepare an environmental impact statement for the proposed temporary and permanent exemptions.
Based upon the foregoing environmental assessment, we conclude that the proposed action will not have a significant effect on the quality of the human environment.
For details with respect to this action, see the licensee's request for the two exemptions dated May 1 and 5, 1989, which is available for public
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6-inspection at the Commission's Public Document Room, Gelman Building, 2120 L Street, N.W., Washington, D.C., and at the Chattanooga-Hamilton County
-l Bicentennial Library,1001 Broad Street, Chattanooga, Tennessee 37402.
Dated at Rockville, Maryland, this 22nd day of September 1989.
FOR THE NUCLEAR REGULATORY COMMISSION SpM4 Suzanne Black, Assistant Director for Projects i
TVA Projects Division Office of Nuclear Reactor Regulation l
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