ML20237E109
| ML20237E109 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 08/26/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20237E103 | List: |
| References | |
| NUDOCS 9808280253 | |
| Download: ML20237E109 (3) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSION D
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NOS317 AND 94 TO FACILITY OPERATING LICENSE NOS. DPR-66 AND NPF-73 DUQUESNE LIGHT COMPANY OHIO EDISON COMPANY PENNSYLVANIA POWER COMPANY THE CLEVELAND ELECTRIC ILLUMINATING COMPANY THE TOLEDO EDISON COMPANY BEAVER VALLEY POWER STATION. UNIT NOS.1 AND 2 DOCKET NOS. 50-334 AND 50-412 1.0 JNIBODUCTION By letter dated December 19,1997, as supplemented June 16, July 9, and July 15,1998, the Duquesne Light Company (the licensee) submitted a request for changes to the Beaver Valley Power ' Station, Unit Nos.1 and 2 (BVPS-1 and BVPS-2), Technical Specifications (TSs). The requerted changes would revise the requirements for the source range (SR) neutron flux chanrels in Modes 2 (Below P-6),3,4, and 5 to incorporate the guidance provided in NUREG-1431, the NRC's improved Standard Technical Specifications with some modifications to address plan'.-specific design features. This change allows (1) the use of attemate detectors provided the required functions are provided, and (2) plant cooldown with inoperable detectors provided the l
shutdown margin accounts for the temperature change. This change would also modify the 4
BVPS-2 TS Table 3.31 Channels To Trip and Minimum Channels Operable requirements to 0 and 1, respectively. This portion of the amendment makes these BVPS-2 requirements consistent with the current BVPS-1 requirements. For both BVPS-1 and BVPS-2, TS Table 4.3-1
'Nould be modified to include a notation exempting the allemate source range detectors from surveillance testing until they are required for operability. The June 16, July 9, and July 15,1998 letters provided clarifying information that did not change the initial proposed no significant hazards consideration determination or expand the amendment request beyond the scope of the March 11,1998, Federal Reaister notice.
2.0 EVALUATION BVPS 1 has four Westinghouse BF3 type SR detectors NE-31, NE 32, NE-33 and NE-34. Out of these four detectors, two detectors N531 and NE-32 are connected to the respective SR channels pre-amplifiers to provide flux signal for monitoring and for protection functions in case the reactor trip breakers (RTBs) are closed and the control rod drive (CRD) system is capable of rod withdrawal. NE 31 and NE 32 are powered by redundant battery backed vital buses 1 and 2 9008280253 900826 PDR ADOCK 05000334 p
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2-respectively. The remaining two detectors, NE-33 and NE-34, are installed as spares with field cabling that runs from the detector to preamplifier boxes of NE-31 and NE-32 respectively without being terminated at these preamplifier boxes. These spare detectors will be designated as attemate detectors. During Mode 2 (below P-6) and Modas 3,4, and 5 of the plant operation, in case any one of the primary SR detectors (NE 31 or NE 32) is not operable, the licensee proposes to terminate the cable of the associated altemate detector (NE-33 or NE-34) at the preamplifier box and substitute the altemate detector for the primary inoperable NE-31 or NE-32 detector.
BVPS-2 has two Westinghouse BF3 type SR detectors (NE-31 and NE-32) normally in service to provide flux signals to control room (CR) indication and annunciation, and are powered by battery backed vital redundant buses 1 and 2 respectively. The BVPS-2 post accident monitoring (PAM) system has two Gamma-Metrics (G/M) detectors (NE-52A and NE 52B) which can monitor the entire rs age from SR to power range. These G/M channels are powered by diesel generator backed emergency 120 vac distribution panels E7 and E8. respectively. These PAM detectors are to be designated as attemate detectors. These allemate detectors can not be directly connected to the primary SR circuits. Therefore, the licensee proposes to use only the indications from the PAM G/M detectors NE-52A or NE 52B, in case any one of the primary SR detectors (NE-31 or NE-32) becomes inoperable during Mode 2 (below P-6) and Modes 3,4, and 5 of the plant operation. A new Note has been added to TS Table 3.3-1 which reads, "May only be used for monitoring purposes without Rod Withdrawal capability until detection functions are modified to permit equivalent alarm and trip functions."
For BVPS-1, the spare detectors are of the exact design to the ones that are used for primary SR instrument loops. Therefore, substituting an attemate (spare) detector for the Inoperable primary detector is basically a one-for-one replacement. For BVPS-2, the readings from the PAM G/M detector instrument loop will be substituted for the indication of any inoperable primary Westinghouse BF3 type detectors only when the system does not have rod withdrawal capability.
L The NRC staff noted that span and scale of BF3 detectors are different from the G/M type detectors and could cause confusion. During a conference call with the NRC staff on June 2,.
1998, licensee personnel informed the NRC staff that the revised plant procedures will make operators aware of span / scale difference of these two types of detectors and clarify ACTION l.
statements, l
In their submittal, the licensee stated that the proposed change will continue to ensure that the l
required SR instrumentation functions will be available during shutdown and startup conditions.
l Also, because the power supplies, installed configurations and other operating parameters l
t-l remain unchanged, none of the assumptions used in the past safety evaluations are voided by I
the proposed modification.
4 Plant cooldown in Modes 3,4, and 5, and xenon decay, are recognized as positive reactivity insertions. However, these effects are accounted for in shutdown margin calculations, and shutdown margin calculations show that the shutdown margin remains essentially unchanged
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and will be able to preclude a criticality event during these Mode changes. The altemate detectors will be able to provide neutron monitoring of flux changes in place of the primary SR 3
detectors assuring the same level of consistency with the existing TSs. Consequently, future l
plant evolutions (changes) can be performed while relying on the altemate detectors if the primary SR detectors are deemed inoperable. Therefore, the proposed change requiring the I
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3-use of attemate detectors in place ofinoperable SR detectors, coupled to the SR detector circuitry providing the same required indications (flux monitoring) and functions, is acceptable,
{j Appropriate changes have been made to Tables TS 3.3-1 and 4.31 to reflect the inclusion of the attemate detectors. Westinghouse improved Standard Technical Specifications (NUREG-1431, Revision 1) Bases describing the SR detectors have been added to the Bases for TS 3/4.4.1 and TS 3/4.3.2. The licensee also included in the Bases a discussion describing the use of altemate detectors, and the suitability of the attemate detectors in place of the SR detectors. The NRC staff has no objections to the proposed changes in the Bases for TS 3/4.4.1 and TS 3/4.3.2. The use of the attemate detectors willin no way incorporate changes that would act to increase the probability of a positive reactivity insertion. The operability requirements will be the same when using the attemate detectors as when using the original SR detectors. Thus the operating requirements will be met.
Based on the foregoing, the NRC staff finds the proposed changes to the BVPS-1 and BVPS-2 TSs to allow the use of altemate SR detectors when the primary souce range detectors are inoperable, acceptable.
3.0 STATE CONSULTATION
in accordance with the Commission's regulations, the Pennsylvania State official was notified of the proposed issuance of the amendments. The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
The amendments change 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 change surveillance requirements. The NRC staff has determined that the amendments involve 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 signincanj lacrease in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding (63 FR 11918). Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmentalimpact statement or environments! assessment need be prepared in connection with the issuance of the amendments.
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 amendments vill not be inimical to the common defense and security or to the health and safety of the publ~;:.
Principal Contributors: A. Attard.-
S. Athavale Date: August 26, 1998
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