ML20077L242
| ML20077L242 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 12/27/1994 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20077L227 | List: |
| References | |
| NUDOCS 9501110265 | |
| Download: ML20077L242 (5) | |
Text
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P W hc i
UNITED STATES y
5 S
NUCLEAR REGULATORY COMMISSION E
f WASHINGTON. D.C. 20086 4001
+ SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 1 w TO FACILITY OPERATING LICENSE NO. DPR-77 AND AMENDMENT NO.184 TO FACILITY OPERATING LICENSE NO. DPR-79 TENNESSEE VALLEY AUTHORITY SE000VAH NUCLEAR PLANT. UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328
1.0 INTRODUCTION
By application dated September 9,1994, the Tennessee Valley Authority (the licensee) proposed an amendment to the Technical Specifications (TS) for Sequoyah Nuclear Plant (SQN) Units 1 and 2.
The requested changes would revise the limiting conditions for operation (LCO), action requirements, surveillance requirements (SR), and associated bases for the cold leg injection accumulators (CLA).
2.0 EVALUATION The proposed changes would affect Specifications 3.5.1.1, 4.5.1.1, and associated Bases for Units 1 and 2.
The proposed changes are as follows:
l 1.
A requirement that power be removed from the CLA isolation valves at reactor coolant system (RCS) pressures above 2000 psig would be added to LC0 3.5.1.1.
2.
Currently TS 3.5.1.1.a Action Statement requires that either an inoperable CLA be restored to operable status within I hour or the plant be in at least hot standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in hot shutdown within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
This applies to all causes for inoperability except that resulting from a closed isolation valve (currently addressed in TS 3.5.1.1.b).
The revision to TS 3.5.1.1.a would include the closed isolation valve as an applicable inoperability, and would exclude inoperability resulting from CLA boron concentration being out of limits.
Additionally, instead of requiring that a hot shutdown condition be reached within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after hot standby, the revision would require that pressurizer pressure be reduced to 1000 psig or less within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after the plant reaches hot standby.
3.
Currently TS 3.5.1.1.b Action Statement applies only to inoperability resulting from a closed isolation valve and requires that either the valve be opened immediately or the plant be in hot standby within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and in hot shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
These requirements have been incorporated into the method used in the proposed change to TS 3.5.1.1.a Action Statement. As revised, TS 3.5.1.1.b would apply only to inoperability resulting from CLA boron concentration out of limits.
It requires that either the concentration be restored to within limits within 9501110265 941227 PDR ADOCK 05000327 P
. 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or the plant be in at least hot standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and pressurizer pressure be reouced to 1000 psig or less within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
4.
Currently SR 4.5.1.1.1.a. Item 1, contains specific wording regarding how verification of contained borated water volume and nitrogen cover pressure t
will be performed. The proposed revision to SR 4.5.1.1.1.a would delete the reference te any specific means of verification.
5.
Currently SR 4.5.1.1.1.b specifies requirements for verification of CLA
[
boron concentration and states that verification is required within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after any solution volume increase of 1 percent of tank volume or greater. The revision to SR 4.5.1.1.1.b would exclude from this requirement any volume additions originating from the refueling water storage tank (RWST). Furthermore, the revision would clarify that verification need only be performed for that CLA that experiences a solution volume increase.
6.
Currently SR 4.5.1.1.1.c requires verification of power removal from isolation valve operators at RCS pressures above 2000 psig by verifying removal of the associated breakers from the circuit. The revision to SR 4.5.1.1.1.c would delete reference to specific means of verification. '
7.
Currently SR 4.5.1.1..t.d verifies automatic opening of the CLA isolation valves when an actual or simulated RCS pressure signal exceeds the P-Il (Pressurizer Pressuru Block of Safety Injection) setpoint or upon receipt of a safety injecticn test signal.
The proposed revision deletes this i
requirement.
8.
Current SR 4.5.1.1.2 and the associated footnote verify operability of each CLA water level and pressure channel by performance of a channel i
functional test and a channel calibration. This SR would be deleted in the proposed revisions.
2.0 EVALUATION 1.
The addition to LCO 3.5.1.1 was proposed to provide consistency with SR 4.5.1.1.1.c and does not represent a new requirement. The SR already j
requires verification of power removal at RCS pressures above 2000 psig.
2.
The revisions to the TS 3.5.1.1.a Action Statement provide consistency with the Westinghouse STS.
If an inoperable.CLA cannot be restored to operable status within the completion time specified in LC0 3.5.1.1, the plant must be brought to an operating condition where the LCO does not apply. As the revised TS indicates, this corresponds to Mode 3 (hot standby) with pressurizer pressure reduced below 1000 psig.
3.
The revisions to the TS 3.5.1.1.b Action Statement provide consistency with the Westinghouse Standard Technical Specifications (STS).
Replacing the current one hour completion time for restoring boron concentration to within limits with a completion time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> reflects the relative safety significance of the boron-related inoperability compared with other
~,
. CLA inoperabilities. Minimum CLA boron concentration is intended to ensure post-LOCA subcriticality. However, with one CLA out of limits, there is no appreciable effect on suberiticality during the reflood phase because of.the increase in boron concentration in the core resulting from boiling, and no effect on the availability of ECCS cooling water.
4.
The revisions to SR 4.5.1.1.1.a (Item 1) and SR 4.5.1.1.1.c provide consistency with the Westinghouse STS by removing specific details regarding how the surveillance will be implemented. These details need not be controlled by TS and deletion of this information does not relax the requirement of the SR.
5.
The revisions to SR 4.5.1.1.1.b reduce unnecessary surveillance activities by performing surveillance only on that CLA which experiences a volume addition of greater than 1 percent of tank volume, and by excluding from applicability any volume addition originating from the RWST.
Since RWST boron limits are within CLA boron limits, any addition from the RWST to the CLA could not cause CLA boron concentration to deviate from these limits.
6.
Item d of SR 4.5.1.1.1 verifies operability of design features which provide automatic opening of the CLA isolation valves.
Since LC0 3.5.1.1, SR 4.5.1.1.1.a.2, and SR 4.5.1.1.1.c already ensure that the CLA isolation valves will open and remain open under those plant conditions where availability of the CLAs is assumed in the accident analysis, Item d represents a redundancy in the TS. Deletion of Item d provides consistency with the Westinghouse STS in that specific design features of the isolation valves need not be controlled by TS.
7.
Deletion of SR 4.5.1.1.2 also provides consistency with the Westinghouse STS. TS control of the calibration and functional testing of CLA level and pressure instrumentation is not necessary. Availability of this instrumentation is not assumed in the safety analyses and SR 4.5.1.1.1.a.1 already ensures verification of the proper CLA level and nitrogen cover-pressure.
8.
The remainder of the proposed TS revisions are administrative in nature and were proposed for purposes of clarification.
These revisions appear in LCO 3.5.1.1.c (footnote), SR 4.5.1.1.1.a.1, and SR 4.5.1.1.1.a.2.
Based on this evaluation, the staff has determined that the TS revisions proposed by the licensee are acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Tennessee State official was notified of the proposed issuance of the amendment.
The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and in surveillance requirements. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (59 FR 51629). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
5.0 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 of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: Harvey I. Abelson
{
Dated: December 27, 1994 i
s E
'Mr. Oliver D. Kingsley, Jr.
SEQUOYAH NUCLEAR PLANT;
. Tennessee Valley Authority cc:
Mr. O. 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 Chatti.nocga, TN 37402-2801 Regional Administrator Dr. Mark O. Medford, Vice President U.S. Nuclear Regulatory Commission Engineering & Technical 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 thattanooga, TN 37402-2801 Mr. Michael H. Mobley, Director Division of Radiological Health Site Vice President 3rd Floor, L and C Annex Sequoyah Nuclear Plant 401 Church Street 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 llH 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 Tennessee Valley Authority P.O. Box 2000 Soddy Daisy, TN 37379