ML20096A833
| ML20096A833 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 04/22/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20096A809 | List: |
| References | |
| NUDOCS 9205110237 | |
| Download: ML20096A833 (5) | |
Text
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f' UNITED STATES n
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.j NUCLEAR REGULATORY COMMISSION p,
c WAFHINGTON, D.C. 30806 4.....f SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 81 TO FACILITY OPERATING LICENSE NO NPF-43 DETROIT EDISON COMPANY 1
FERMI-2 DOCKET NO. 50-341 t
1.0 -1NTRODUCTIOff -
By letter dated September 11, 1990, the Detroit Edison Company (Deco or the licensee) requested an amendment to the Technical Specifications (TS)-appended to Facility Operating License No. NPF-43 for fermi-2. Tha licensee also provided additional information by letters dated Novembe 11 and 14, 1991.
This additional information-was for-clarification-only and did not-n.odify the proposed TS or the conclusions reached in the staff's no significant hazards consideration determination (56 FR 15640). The proposed ainendment revises TS Section 3/4.7.2 to provide clarification of those redundant components that constitute an OPERABLE Control Room Emergency Filtration System cubsystem and the: actions required in the event that one or both subsystems are inoperable.
Additionally, changes to the Surveillance Requirements were requested to revise the' listing of actuation signals for the system and to minimize unnecessary. run time for the recirculation and emergency.nakeup air filter train.
.The fermi-2 control room emergency filtration system (CREFS) differs-from a typical CREFS design upon which the Standard Technical Specifications (ST5) are based. The Fermi-2 CREFS is not completely broken up into two redundant subsystems each capable of performing-its design function. The Fermi-2 CREFS is configured into two_ subsystems of redundant: components which are capable of establishing the required flow path through non-redundant duct work and air filter trains. Therefore, Deco has~ proposed the subject TS change to provide clarification of those redundant components which constitute an operable CREFS subsystem and the actions _ required in the event that one or both subsystems or the non-redundant duct work and/or air filter trains are inoperable.
The L
proposed changes are summarized as follows:
(1)- Revision of the Limiting Condition for Operation (LCO) to better reflect j
the system configuration in regards to redundant and non-redundant components.
(2) _ Revision of action requirements to correspond with the LCO changes-of (1) above and to accommodate surveillance activities which may be required
-during power operation.
(3) levision of the monthly system operation surveillance to eliminate unnece!,sary operation of the system tilter trains.
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' (4) Revision of the surveillance requirement for system actuation instrumentation to delete the reactor building ventilation exhaust radiation monitor from the listing of actuation signals for the CREFS.
2.0 UAl.UATION Proposed Chance Number ?
Revision of the LCO to better reflect the CREFS configuration with respect to redundant and non-redundant components.
The LCO it. the current TS Section 3.7.2 describes the system requirements in a mar.ner which does not clearly show the sy: tem configuration.
The proposed TS change recommends:an LCO that lists the redundant subsystems more completely.
The proposed LCO adds chiller units and dampers required to support system operation as required TS equipment.
In addition, a description of the flow paths capable of supplying emergency makeup air to the control room and recirculating control room air through the emergency recirculation air filter train-is added to the proposed LCO.
The revised CREFS LCO will provide a clearer understanding and a more consistent application of the TS requi.ements.
1his will reduce the chance of misinterpretation and misapplication of the requirements of the 15 and thus enhance safety during plant operation.
The staff has reviewed the proposed change and concurs with the licensee's rationale for the change and finds the propo ed TS acceptable.
Proposed Change Number 2 Revision of action requirements to correspond with the LCO of Proposed Change 1 above and to accommodate surveillance activities which may be required during power operation.
This change is limited to ACTION Statements b, and c. of the LC0 of 15 Section 3.7.2.
In both cases, the nomenclature is editorially modifiea to be consistent with the proposed changes to the LCO. The allowed times to take the required actions have not been changed.
in addition, a new provision is proposed to be added to ACTION Statement b.1, which addresses the inoperability of non-redundant equipment while in Operational Conditions 1, 2 or 3.
C srently, the TS would require the plant to be in Hot Shutdown within six hours should the non-redundant duct work become inoperable.
The proposed TS would allow a delay of six hours for the purpose of performing surveillances which may be required for power operation.
In their November 11, 1991 letter, the licensee indicated that the proposed delay would be limited to the performance of TS 4.7.2.c due to painting, fire, or chemical release in any ventilation zone communicating with the CREFS or to
_ erform TS 4.7.2.d.
Technical Specification 4.7.2.d requires a charcoal p
sample be taken following every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of charcoal adsorber operation.
if unusual periods of filter operation occur, performance of TS 4.7.2.d could be
~
- required during plant operation.
This provision is expected to be used very infrequently.
The licensee has further committed to submt a special report to the NRC within 30 days describing the circumstances of any use of this provision. This reporting requirement will be included in the plant administrative procedures for regulatory reporting requirementi.
It will also be included in the charcoal sampling procedure for the CLEi'..
In summary the proposed change would:
Eliminate the need to enter a Hot Shutdown action for an operebility of a known, infrequent and limited duration.
Provide the safety benefit of eliminating simultaneous evolutions and unnecessary plant thermal cycling.
Reflect a fermi-2 design difference from the design on which the Standard lechnical Specifications were based.
Based on the above evaluation, the staff concurs with the licensee's rationale for the above proposed change to the action requirements and find te proposed change accepta)le.
Eroposed Chanae Number 3 Revision of the monthly system operation surveillance to climinate unnecessary operation of the system filter trains.
Technical Specification 4.7.2.b Surveillance Requirement currently requires that the control room emergency filtration system shall be demonstrated OPERABLE at least once per 31 days on a staggereo basis, by initiating fan operation from the control room, and establishing flow through the high-efficiency particulate air (HEPA) filters and charcoal absorbers, and verifying that the system operates for at least ten hours with the associated emergency makeup inlet air heater operable. As stated in the Bases of the TS, this ten-hour operation is to be continuous.
Since there aro two subsystems, each of which utilizes a shared recircidation and emergency makeup air train, this results in operating the filtration train twice monthly for ten hours each time for a total of 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> per 31 days. This requirement causes unnecessary filter train operation and a reduction in filter life.
Regulatory Position C.4.d of Regulatory Guide 1.52, Revision 2, March 1978, requires that each Engineered Safety feature (ESF) atmosphere cleanup train be operated at least. ten hours per month with the heaters in service in order to reduce the buila-up of moisture on the absorbers and HEPA filters.
The proposed TS change would revise the surveillance requirement to reduce the run time of 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> per 31 days, currently required by the TS, to ten hours per 31 days as recommended by Regulatory Guide 1.52.
In addition, each redundant subsystem will be required to be started from the control room and operated for a minimum of 15 minutes.
To assure that the testing is as uniform as possible, the subsystem used to satisfy the ten-hour run time requirement will be on a staggered basis such that each redundant subsystem is utilized for the ten-hour run at least every 62 days.
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4 The staff has reviewed the proposed change and concurs with the licensee's ratienait for the change and finds the proposed TS acceptable.
Proposed ChanaLMber..4 f
Revision of the surveillance requirement system actuation instrumentation to delete the Reactor Building Ventilation Exhaust Radiation Monitor from the listing of actuation signals.
The licensee has proposed to delete the Reactor Building Ventilation Exhaust Radiation Monitor from the list of actuation signals listed in TS 4.7.2.e.2.
In a previous application for amendment, Deco requested removal of the Turbine Building and Radwaste Ventilation Exhaust Radiation Monitors from the above TS list.
This request was granted by the flRC staff in Amendment No. 7 to the Fermi-2 Operating License.
In the supporting Safety Evaluation, the NRC staff concluded that:
Signals from the control room outside air radiation monitors, as well as the reactor protection signals, are sufficient to initiate the control room emergency ventilation mode, such that the dose guidelines of General Design Criteria (GDC) 19 are met with respect to all design basis airborne radioactivity release accidents, including the [ Loss-of-Coolant Accident) LOCA.
The staff further stated:
The additional emergency ventilation signals, as listed in TS 3/4.7.2, are not necessary to meet GDC 19 requiremen'.s and, hence, represent signals of marginal importance.
With the Reactor Building Ventilation Rado.. ion Monitor inoperable, the CREFS must ce considered inoperable and the appropriate action taken.
The resulting impact on plant operations is unwarranted since the CREFS can still perform its intended function and is not degraded with the Reactor Building Ventilation Radiation Monitor inoperable.
The Control Center Inlet Radiation Monitor and fuel Pool Ventilation Exhaust Radiation Monitor signals remain as listed in the TS actuation signals as well as the High Drywell Pressure and Low Reactor Vessel level Water level signals.
The Fuel Pool Ventilation Exhaust Radiation Monitor signal is retained to provide diversity to the Control Center Inlet Radiation Monitor signal for a Fuel Handling Accident scenario, since this scenario would not result in changes to reactor water level or drywell pressure.
The staff has reviewed the proposed change and concurs with the licensee's rationale for the change and finds the proposed TS acceptable.
Based on the above evaluations, the staff finds the proposed changes to the TS acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Michigan State official was notified of the proposed issuance of the amendment. The State official had no connents.
4.0 fBVIRONMENTAL CONSIDERATION The amendment changes 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 c.hanges in surveillance re(uirements.
The staff has determined that tN amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents which 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 involv*s no significant hazards consideration and there has been no pub 1' comment on such finding (56 FR 15640). Accordingly, the amendment meets the eligibility criteria for categoricel exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.21,sj, no environmental im)act statement or environmental assessment need be prepared :n connection wit 1 the issuance of the amendment.
5.0 CONCLUSION
The staff 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 pt. lic.
Principal Contributor: John Stang Timothy Colburn Date: April 22, 1992 l
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