ML20149D874
| ML20149D874 | |
| Person / Time | |
|---|---|
| Site: | Hope Creek  |
| Issue date: | 07/09/1997 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20149D865 | List: |
| References | |
| NUDOCS 9707180023 | |
| Download: ML20149D874 (4) | |
Text
.
aun gk UNITED STATES g
E NUCLEAR REGULATORY COMMISSION j
f WASHINGTON, D.C. 20666 4 001
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- p$
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 99 TO FACILITY OPERATING LICENSE NO. NPF-57 PUBLIC SERVICE ELECTRIC & GAS COMPANY l
ATLANTIC CITY ELECTRIC COMPANY j
HOPE CREEK GENERATING STATION l
j DOCKET NO. 50-354
1.0 INTRODUCTION
By letter dated March 31, 1997, Public Service Electric & Gas Company (the i
i licensee) requested changes to the Hope Creek Generating Station (HCGS)
Technical Specifications (TS0). The proposed changes to the TSs would change TS Section 3.6.5.3.2, " Filtration, Recirculation and Ventilation System (FRVS)," to provide an appropriate Limiting Condition for Operation and ACTION Statement that reflects the design basis for the FRVS. A second proposed i
change to TS 4.6.5.3.2b would permit the FRVS heaters to be OPERABLE rather i
than ON during the 31-day test.
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2.0 DISCUSSION l
The FRVS recirculation system is described in the HCGS Updated Final Safety
{
Analysis Report, Section 6.8.
This system consists of six 25%-capacity units,
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each consisting of a fan and filter unit located inside the Reactor Building.
l The filter unit consists of an electric heating coil, high efficiency particulate air (HEPA) filter, charcoal filters, HEPA after-filters, and water j
cooling coils. The water cooling coils are supplied by the Safety Auxiliary Cooling System (SACS).
Following a Reactor Building Isolation Signal, all six of the FRVS units start (two of the units are manually stopped and placed in
" Auto" mode) and function to reduce offsite doses significantly below 10 CFR j
i Part 100 guidelines during a loss-of-coolant accident, refueling accident, or any other condition resulting in high radioactivity in the Reactor Building.
In Licensee Event Report 97-002, dated February 14, 1997, the licensee informed the NRC staff that:
On January 17, 1997, during preparation of a 10CFR50.59 safety evaluation to support a plant modification, an inconsistency was discovered between the Hope Creek Generating Station (HCGS) Technical Specifications (TS) and the design basis documents of the Filtration, Recirculation, and i
Ventilation System (FRVS). TS 3.6.5.3.2 does not assure the availability of the prescribed number of FRVS recirculation units to fulfil system functions in the presence of a postulated single failure in accordance.
with the updated Final Safety Analysis Report (UFSAR).
9707180023 970709 PDR ADOCK 05000354 P
PDR l
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.2-Specifically, given the TS (3.6.5.3.2) required complement of only five 3
of the total of six recirculation units, and in the event of a design basis Loss of Coolant Accident (LOCA) with a Loss of Offsite Power (LOOP) l and either the active single' failure of the "A" or "B" Emergency Diesel Generator (EDG) or the passive failure of one Safety Auxiliaries Coolin~g System (SACS) loop (train), the available number of recirculation units i
would have been less than that assumed in the UFSAR..
In order to address the issues associated with LER 97-002, the licensee has
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proposed that the number of'FRVS units, required to be operable per.TS l
3.6.5.3.2 be-increased from five to six units and suitable changes to the TS l
ACTION. statement to accommodate the increased number of FRVS units that must l-be operable. The licensee has also proposed a change to the surveillance requirements for the FRVS electric heating coils.
The proposed change to TS 4.6.5.3.2b would permit the FRVS heaters to be'0PERABLE rather than ON during a 10-hour test every 31 days.
3.0 EVALUATION As indicated above, the HCGS UFSAR assumes that four FRVS recirculation units are operating, two units having been manually stopped and maintained in standby, following a Reactor Building Isolation Signal.
In the event of a coincident Loss of Offsite Power (LOOP), and the worst single active failure (the "A" or "B" Emergency Diesel Generator (EDG)), two of the available FRVS recirculation units would be inoperable.
In this regard, the "A" EDG provides power to the "A" and "E" FRVS recirculation units, the "B" EDG provides power to.the "B" and "F" FRVS recirculation units and the "C" and "D" EDGs provide power to the "C" and "D" FRVS recirculation units, respectively.
Potential loss of SACS cooling would involve a " passive" failure and need not be considered in the initial stages of a LOCA. 'Accordingly, all six FRVS recirculation units must be operable at the initiation of the LOCA to assure that at least four units remain operable to ameliorate the consequences of a LOCA coincident with LOOP and the worst singh, active, failure.
Consistent with the above, the licensee has proposed a change to TS 3.6.5.3.2 to increase the required number of operable FRVS recirculation units from five to six units. This proposed change is acceptable because it assures that at least four FRVS recirculation units will be available to ameliorate the consequences of a LOCA with coincident LOOP.
The licensee has also proposed changes to the TS 3.6.5.3.2 ACTION statement's which require remedial action when one or more FRVS recirculation units are inoperable:
1.
ACTION statement "a." currently requires remedial action within 7 days when one FRVS recirculation unit becomes inoperable. The licensee has proposed to change-this ACTION statement to apply to "one or two" inoperable FRVS recirculation units. This proposed change is conservative, and acceptable, in that it requires the licensee to restore up to two inoperable FRVS recirculation units in the same time frame as l
is currently required for one FRVS recirculation unit and it is compatable with the requirement to have six operable FRVs units as contained in the proposed change to TS 3.6.5.3.2.
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ACTION statement "b." currently requires the suspension of specified t~
activities (handling of irradiated fuel, CORE ALTERATIONS, or operations l
with the potential of draining the reactor vessel) when two FRVS recirculation units become inoperable during specified COLD SHUTDOWN or i-REFUELING conditions. The-proposed ACTION statement would require the suspension of specified activities.when three or more FRVS recirculation-
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units become inoperable.
In both the existing and proposed TS, the 4
i specified activities may continue if four FRVS recirculation units are operable. Since the proposed ACTION statement provides an equivalent i
degree of FRVS redundancy, compared to the existing requirement, it is acceptable.
3.
The licensee has proposed a new ACTION statement "c." to address the o
inoperability of three or more FRVS recirculation units.
The associated remedial action would require the facility to be, "...in at least HOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following'24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />." Since the proposed ACTION statement "c." could be applicable to a situation where all of the FRVS recirculation units are inoperable, the provision of sufficient time for an orderly facility shutdown is-appropriate and is acceptable.
i With regard to FRVS recirculation unit surveillance, TS 4.6.5.3.2b requires
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the conduct.of a test of the FRVS recirculation units every 31 days for 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> to assure operability and reduce the build-up of moisture on the carbon absorbers and HEPA Filters. The TS requires that the heater coils be "on" for the duration of the test. The Hope Creek licensee has been testing the FRVS recirculation units in a manner that does not provide compliance with TS~4.6.5.3.2b.
Specifically, the licensee has been energizing the heaters 1
only at the beginning of the 10-hour test, every 31 days, to assure that they are " operable." During the remainder of the test, the heater coils are energized as necessary to maintain constant humidity but are not continuously energized.
Regulatory Guide (RG) 1.52, " Design, Testing, and Maintenance Criteria for Post Accident Engineered-Safety-Feature Atmosphere Cleanup System and Filtration and Absorption Units of Light-Water-Cooled Nuclear Power Plants,"
Revision 2, provides the design basis for the FRVS.
Regulatory Position C.4.d of RG 1.52 states that, "Each ESF atmospheric cleanup train should be operated at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> per month, with the heaters on (if so equipped), in
. order to reduce the buildup of moisture on the absorber and HEPA filters."
The licensee has indicated conformance to this guidance in the HCGS UFSAR, Table 6.8-3, and does not note any deviations in UFSAR Section 1.8.1.52.
It is clear from TS 4.6.5.3.2b (consistent with RG 1.52, C.4.d) that the purpose of the test, to reduce the buildup of moisture on the charcoal absorbers and the HEPA filters, is to be accomplished by utilizing the energized heater coils during the full 10-hour duration of the test, given the current system design. Accordingly, after careful review, the NRC staff has concluded that the licensee's request to change TS 4.6.5.3.2b to permit the FRVS heaters to be OPERABLE rather than ON during the 10 hour1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> test, every 31 days, cannot be approved.
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l t-The NRC staff notes that the Bases associated with TS 4.6.5.3.2b should be clarified to state that the heater coil (heaters) should be "0N" rather than "0PERABLE" for the duration of the 10-hour monthly test.
This change to the Bases can be made at the convenience of the licensee.
4.0 STATE CONSULTATION
i In accordance with the Commission's regulations, the New Jersey State Official was notified of the proposed issuance of the amendment.
By letter dated j
April 28, 1997, the State official indicated that there were no comments.
5.0 ENVIRONMENTAL CONSIDERATION
I The amendment changes a requirement with respect to installation or use of a faci 1*ty component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluent 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 (62 FR 27798). Accordingly, the amendment meets the eligibility criteria for cateurical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 Cia 51.22 environmental assessment need be prepar(b) no environmental impact statement or ed in connection with the issuance of the amendment.
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 of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
D. H. Jaffe Date: July 9, 1997 r s,
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