ML20082C721
| ML20082C721 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 07/05/1991 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20082C718 | List: |
| References | |
| NUDOCS 9107220283 | |
| Download: ML20082C721 (4) | |
Text
.~_n j e H%,
[
h bNITED $TATES I i<
S NUCLEAR REGULATORY COMMISSION W AsHINo T oN. D. C, 20S55
...../
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REAC10R REGULAT!ON RELATED TO AMENDMENT NO. 143 TO FACILITY OPERATING LICENSE NO. DPR-46 NEBRASKA PUBLIC POWER DISTRICT COOPER NUCLEAR STATION DOCKET NO. 50-298
1.0 INTRODUCTION
By letter dated August 31, 1989 as supplemented by letter dated June 7, 1991, Nebraska Public Power District (the licensee) submitted a request for changes to the Cooper Nuclear Station, Facility Operating License No. OPR-46.
The proposed amendment would change the expiration date of the operating license front June 4, 2008 to January 18, 2014.
This extends the duration of the license to 40 years from the date of issuance of the operating license.
The license was ini_tially issued for a duration of 40 years from the date of issuance of the construction permit.
The June 7, 1991, letter provided clarifications regarding the licensee's Reactor Vessel Surveillance Program and did not change the action noticed or affect the initial proposed no significant hazards consideration determination.
2.0 DISCUS $10N Section 103.c of the Atomic Energy Act of 1954 provides that the license is to be issued for a specified period not exceeding 40 years.
10 CFR 50.51 specifies that each license will be issued for a fixed period of time not to exceed 40 years from the date of issuance.
10 CFR 50.56 and 10 CFR 50.57 allow the issuance of an operating license pursuant tn 10 CFR 50.51 after the construc-tion of the facility has been substantially completed, in conformity with the construction permit and when other provisions specified in 10 CFR 50.57 are met.
The currently licensed term for Cooper Nuclear Station is 40 years commencing with the issuance of the construction permit (June 4, 1968).
Accounting for the time that was required for plant construction, this represents an ef fective operaung license term of 34 years and 5 months.
Consistent with Section 303.c of the Atomic Energy Act and Sections 50.51, 50.56, and 50.57 of the Commission's regulations, the licensce, by its application of August 31, 1989, seeks extension of the operation license term for the Cooper Nuclear Station such that the fixed period of the license would be 40 years from the date of the operating license issuance.
3.0 EVALUATION The licensee's request for extension of the operating license is based on the fact that a 40 year service life was considered during the design and construc-tion of the plant.
Although this does not mean that some comoonents will not wear out during the plant lifetime, design features were incorporated which maximize the inspectability of structures, systems and equipment.
Surveillance 9107220283 910705 PDR ADOCK Ob0 0
P
.g.
and maintenance practices which have been implemented in accordance with the ASME code and the facility Technical Sptcifications provide assurance that any unexpected degradation in plant equipment will be identified and corrected.
3.1 Electrical Equipment The staff evaluatea the safety implications of extending the Cooper operating license on safety-related electrical systems and equipment.
The evaluation considered the licensee's response to 10 CFR 50.49 and other programs associated with the environmental qualification of electrical equipment.
For the electrical equipment identified as important to safety, aging reviews have either determined a replacement schedule or demonstrated that the equipment will perform satisfac-torily for the 40 year plant design lifetime, for this equipment, the staff believes that the licensee has controls in place to ensure required surveillances and maintenance are performed.
The NRC Safety Evaluation associated with the licensee's environmental qualification program was issued on January 30, 1985, and NRC Inspection Report 50-298/89-13 documented-the close out of the last environmental qualification open items.
Additional environmental qualification issues may be occasionally identified and shall be resolved ab they arise.
Based upon this evaluation, the staf f concludes that electric I systenis design, electrical equipment selection and application, and environmental qualification of electrical equipment either considered the effects of a 40 year operational lifetime or will not be affected by a 40 year operational lifetime.
3.2 Mechanical Equipment The Cooper reactor vessel was designed considering the effects of 4d years of operation with a plant capacity factor of 80% (32 EfPY).
The initial vessel material surveillance program consisted of three surveillance capsules with the first. capsule withdrawn and analyzed after operating cycle 9.
As described in the letter dated June 7, 1991, the licensee plans to reconstitute those specimens within the second capsule which will be withdrawn during the fall 1991 refueling outage, lhese reconstituted specimens will be reinserted into the reactor vessel during the 1993 refueling outage.
The reconstitution of the capsule withdrawn in 1991 is equivalent to a fourth capsule and therely makes the licensee's surveillance program consistent with the requirements of ASTM E185-82 and 10 CFR Part 50 Appendix H.
The withdrawal schedule f or the recon-stituted capsule and the original thir. capsule will be determined based upon the analysis of the capsule withdrawn in 1991 and Technical Specificiation 4.6.A.3 will be revised accordingly, lhe radiation induced material property changes are incorporated into the Technical Specification pressure / temperature limits to ensure complia.c,e with Appendix G.
The stress analyses and load combinations for the reactor vessel were evaluated for the cycles expected throughout _a 40 year life a'nd are monitored in accordance with Technical Specification 6.4.2G and ASME code requirements to ensure the analyses bound actual plant operation.
Intergranular Stress Corrosion Cracking (IGSCC) has affected the recirculation system and connected piping at several BWRs.
In response to the discoveries of degraded piping, the staff issued Generic Letter 88-01 which, along with
~
> V NUREG-0313, Revision 2, " Technical Report on Material telection and Processing Guidelines for BWR Coolant Pressure Boundary piping," provided the staff's position regarding acceptable methods to address the IGSCC issue.
By letter dated August 3, 1988, the licensee described the actions taken and planned in response to the IGSCC issues and Generic letter 88-01.
The licensee's response is currently under staff review.
Other mechanical equipment such as pumps and valves are routinely tested and inspected in accordance with programs required by various industry codes and standards and approved by the staff.
The Cooper Inservice Inspection Program and Inservice Testing Program are periodically submitted to the NRC for review.
These programs, as supplemented by NRC and industry programs addressing specific problems, are considered to adequately ensure the identification and correction of problems associated with plant equipment.
- 3. 3 Structures The plant buildings at Cooper are constructed of reinforced concrete and steel, Industrial experience has shown that a service life in excess of forty years can be expected.
Surveillance, inspection and testing programs are in place to monitor the condition of all important structure so that any degradation can be identified and corrected.
This includes local and integrated leak rate testing of the primary containment as reoutred by Technical Specification 4.7.
The construction of the plant structures and the ongoing testing and inspection programs ensure that the structures are adequate for an operating lifetime of 40 years.
3.4 Summary of findings The NRC staff concluded in the Environmental Assessment that the annual radiological effects during the additional years of operation that would be authorized by the proposed license amendment are not more than were estimated in the final Environmental Statement or subsequent evaluations (10 CFR Part 50, Appendix 1 Radiological Ef fluent Technical Specifications (Amendment No. 89),
etc) and are acceptable.
The staff concludes from its considerations of the design, operation, testing and monitoring of-the mechanical and electrical equipment, structures, and reactor vessel and pressure boundary piping that an extension of the Cooper operating license to a 40 year service life is acceptable.
The revision of the license expiration date is consistent with the USARs, SERs, and submittals made by the licensee and there.#
reasonable assurance that the unit will con-tinue to operate safely for tht additional 5 years and 7 months authorized by the amendment.
The plant has and is expected to continue to operate in compliance with the Commission's regulations and issues associated with plant degradation have been adequately addressed.
In summary, the staf f finds that the extension of the operating license f or Cooper Nuclear Station to January 18, 2014, is consistent with the final Environmental Statement, the Safety Evaluation Reports, and subsequent Safety Evaluations and that the Commission's previous findings are not changed.
-.__2.,,_
_ _..,., _ _ - ~
. 4.0 $1A1E CONSULAT10N In accordance with the Commission's regulations, the Nebraska State official i
was notified of the proposed issuance of the amendment.
The State official had no comment.
5.0 ENVIRONMENTAL CONSIDERATION
A Notice of Issuance of Environmental Assessment and finding of No Significant Impact relating to the proposed extension of the facility Operating License expiration date for Cooper Nuclear Station was published in the federal Register on June 5, 1991 ($6 FR 25701).
6.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered _by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance u.1 the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
W. Reckley, NRR Date:
July 5,1991 I
i-l l-.
l l
l
...--._,m
--__._-,J,_-..,_,.,_.._,.._....,__...._.
.,,,,_..,.._,_-,,_......,.,,.._.--,m.
_-_.,-_2