ML20082V284
| ML20082V284 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 05/02/1995 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20082V277 | List: |
| References | |
| GL-90-06, GL-90-6, NUDOCS 9505090160 | |
| Download: ML20082V284 (5) | |
Text
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NUCLEAR REGULATORY COMMISSION 11 ff WASHINGTON, D.C. 20555 4001 Q*.C"74 /
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SAFETY EVALUATION BY THE CFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.198 TO FACILITY OPERATING LICENSE NO. DPR-32 AND AMENDMENT NO.198 TO FACILITY OPERATING-LICENSE NO. DPR-37 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION. UNIT NOS. 1 AND 2 DOCKET NOS. 50-280 AND 50-281
1.0 INTRODUCTION
On June 25, 1990, the staff issued Generic Letter (GL) 90-06, " Resolution of Generic Issue 70, ' Power-0perated Relief Valve and Block Valve Reliability,'
and Generic Issue 94, ' Additional Low-Temperature Overpressure Protection for Light-Water Reactors,' Pursuant to 10 CFR 50.54(f)." The GL represented the technical resolution of the above-mentioned generic issues.
Generic Issue 70, " Power-Operated Relief Valve and Block Valve Reliability,"
involves the evaluation of the reliability of power-operated relief valves (PORVs) and block valves and their safety significance in pressurized water reactor (PWR) plants. The GL discussed how the PORVs are increasingly being relied on to perform safety-related functions and the corresponding need to improve the reliability of both PORVs and their associated block valves.
Proposed staff positions and improvements to the plant's technical specifications (TS) were recommended to be implemented at all affected facilities. This issue is applicable to all Westinghouse, Babcock & Wilcox, and Combustion Engineering designed facilities with PORVs.
Generic Issue 94, " Additional Low-Temperature Overpressure Protection for Light-Water Reactors," addresses concerns with the implementation of the requirements set forth in the resolution of Unresolved Se'ety Issue (USI) A-26, " Reactor Vessel Pressure Transient Protection (Overpressure Protection)."
The GL discussed the continuing occurrence of overpressure events and the need to further restrict the allowed outage time for a ?ow-temperature overpressure protection channel in operating modes 4, 5, and 6.
This issue is only applicable to Westinghouse and Combustion Engineering facilities.
By letter dated June 28, 1991, the Virginia Electric and Power Company (the licensee) proposed changes to the Surry Power Station, Units 1 and 2 TS in response to GL 90-06.
2.0 EVALUATION FOR GENERIC ISSUE 70 The actions proposed by the NRC staff to improve the reliability of PORVs and block valves represent a substantial increase in overall protection of the public health and safety and a determination has been made that the attendant 9505090160 950502 DR ADOCK 050 280 z
costs are justified in view of this increased protection. The technical i
findings and the regulatory analysis related to Generic Issue 70 are discussed in NUREG-1316, " Technical Findings and Regulatory Analysis Related to Generic Issue 70 - Evaluation of Power-Operated Relief Valve Reliability in PWR Nuclear Power Plants."
The following is a summary of the proposed changes to the TS as they relate to Generic Issue 70:
i Paaes 3.1-4. 3.1-4a. 3.1.5. 3.1.5c. 4.1.1 and 4.1.la o
Page 3.1-4 has been reformatted to accessiodate the additional action statements for PORVs. Page 3.1-4a is being added to accommodate the additional requirements.
o On page 3.1-4a, the requirement for OPERA 8LE P0p'Is is being changed from "whenever the reactor keff>0.99" to "whenever reactor coolant average temperature is >350'F "
o On page 3.1-4a, the footnote has been added to permit the calibration of the PORV control circuit from the low-temperature overpressure protection setpoints to the high pressure setpoints.
The valves are still capable of being manually cycled to mitigate j
the consequences of a steam generator tube rupture, if necessary.
o On pages 3.1-4a and 5, the operability requirements for the PORVs and the associated block valves are being incorporated into 3.1.5.a through e.
The words in the PORV operability requirements of 3.1.6.b, c, and d have been modified from "with excessive or other than excessive seat leakage" to " capable or not capable of being manually cycled." The action statements force the plant to shutdown and cooldown to <350*F if the valve (s) cannot be returned to OPERABLE status or capable of being manually cycled. This change will ensure the operability of the PORV to mitigate the consequences of a steam generator tube rupture. Spec;fications 3.1.6.b and c, which address the required actions when the PORV is not cepable of being manually cycled, have included an additional provision to allow exiting the action statement when the PORV is capable of being manually cycled.
o The statement, "the provisions of specification 3.0.4 are not applicable," is not included. Surry TS do not have the 3.0.4 requirement.
o On page 3.1-5c, the basis section is being changed to include a discussion of the use of the PORVs in the mitigation of a steam generator tube rupture event and ncte that the PORVs are tested during refueling outages, but not at power.
In addition, the l
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a d
i F phrase " capable.of beir.g" is being removed from the sentence that i
describes the power supplits for the PORVs and block valves. The-PORVs and block valves are powered from the emergency buses.
m (ki pages 4.1-1 and 4.1-la, a statement' that incorporates the o
Section XI testing requirements is being added to Specification 4.1.B.1, as well as additional surveillance requirements for the PORVs and their actuation system are being included.
These valves-are in the existing Section XI program and are being tested accordingly.
The staff has reviewed the licensee's proposed modifications to the TS. Since the proposed modifications are consistent with the staff's position with respect to the GL, and found to be justified'in the above-mentioned regulatory i
analysis, the staff finds the proposed modifications acceptable.
3.0 EVALUATION FOR GENERIC ISSUE 94 The actions proposed by the NRC staff to improve the availability of the.loww temperature overpressure protection (LTOP) system represents a substantial increase in the overall protection of the public health and safety and a determination has been made that the attendant costs are justified in view of-this increased protection. The technical findings and the regulatory analysis related to Generic Issue 94 are discussed in NUREG-1326 " Regulatory Analysis for the Resolution of Generic Issue 94, Additional Low-Temperature Overpressure Protection for Light-Water Reactors."
The following is a summary of the proposed changes to the TS as they relate to i
Generic Issue 94:
Paaes 3.1-22. 23. 23a. and 21 o
Page 3.1-22 and 23a were reformatted and added, respectively, to accommodate the additional requirements. The References are moved l
from page 3.1-23 to 3.1-22.
o On page 3.1-23, additional surveillance requirements are being added to 3.1.G.I.b.(1) to verify charging pump operability prior to going below 350'F and once.every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter.
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- addition, statement 3.1.G.I.b.(1)(c) is being added to allow two charging pumps to be operating momentarily when-' switching pumps if the reactor coolant average temperature is <350*F.
o On page 3.1-23, new requirements 3.1.G.I.b.(2)(a), (b), and (c) are being included, along with a 6-hour period wnen the discharge isolation valves can be opened for periodic testing of the discharge isolation and check valves. Surveillance requirements are being added to verify accumulator isolation prior to going below 350*F and once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter.
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o-On page 3.1-23, surveillance requirement 3.1.G.I.b.(3)(a) is being j
added to verify the block valves are open every 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> when the PORVs are providing overpressure protection.
o On page 3.1-23a, surveillance requirements 3.1.G.I.b.(5)(a) and (b) are being modified to verify the RCS vent path every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> when the vent path is unlocked open and every 31 days if the vent i
path is locked open.
o On page 3.1-23a, the operability requirements 3.1.G.2.a. and b.
l for the PORVs are being changed to provide two different allowed outage times for PORV inoperability consistent with the GL.
In Intermediate Shutdown with the reac W coolant average temperature
>200*F but <350*F the PORV can be im perable for 7 days before the RCS must be depressurized and a vent r th established. However, a
in Cold Shutdown or Refueling operations, the PORV can only bs inoperable for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> before the reactor coolant system (RCS) must be depressurized and a vent path established.
o On page 3.1-24, the wording of 3.G.2.d is being modified for clarification.
Table 4.1-2A o
On page 4.1-9c, a channel calibration is being added to item 16.
This surveillance is being moved from 4.1.8.
Also, the appropriate UFSAR section is being referenced for items 16 and 17.
o un page 4.1-9c, Surveillance requirements for the PORV control circuits are being included as item 18. This requirement is being moved from 4.1.B.
o On page 4.1-9d, items 18, 19, 20, 21, and 22 are being renumbered as 19, 20, 21, 22, and 23.
P Throughout the change, editorial changes are being made to capitalize defined words and provide consistent terminology.
The staff has reviewed the licensee's proposed modifications to the Surry Power Station, Units 1 and 2 TSs. Since the proposed modifications are consistent with the staff's position with regard to the GL and, justified in the above-mentioned regulatory analysis, the staff finds the proposed
- modifications to be acceptable.
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4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Virginia State official was notified of the proposed issuance of the amendment. The State official had no comments.
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..w 5.0 ENVIR0fetENTAL CONCLUSION The amendment involves a change in a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes in surveillance requirements. The 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 exposures. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration and that there has been no public comment of such finding (56 FR 49929).
Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 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.
6.0 CCNCLUSION
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The Commission has concluded, L>ed on the considerations discussed abose,
.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. The staff therefore concludes that the proposed changes are acceptable.
Principal Contributors:
Robert Kirkwood (Generic Issue 70)
Edward Throm (Generic Issue 94)
Bart Buckley, Project Manager Date:
May 2,1995 l
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