ML20211N875
| ML20211N875 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 06/30/1986 |
| From: | Udy A EG&G IDAHO, INC. |
| To: | NRC |
| Shared Package | |
| ML20211N848 | List: |
| References | |
| CON-FIN-A-6483, RTR-REGGD-01.097, RTR-REGGD-1.097 EGG-NTA-7277, EGG-NTA-7277-DRFT, TAC-51115, NUDOCS 8612180331 | |
| Download: ML20211N875 (22) | |
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ENCLOSURE EGG-NTA-7277 CONFORMANCE TO REGULATORY GUIDE 1.97 OYSTER CREEK NUCLEAR GENERATING STATION A. C. Udy Published. lune 1986 EG&G Idaho, Inc.
.s Prepared for the U.S. Nuclear Regulatory Comission l
Washington, D.C.
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Under DOE Contract No. DE-AC07-761001570 FIN No. A6483 i
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A8STRACT This EG&G Idaho, Inc., report reviews the submittals for Regulatory Guide 1.97, Revision 2, for the Oyster Creek Nuclear Generating Station.
Any exceptions to Regulatory Guide 1.97 are evaluated and those areas where sufficient basis.for acceptability is not provided are identified.
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Docket No. 50-219 TAC No. 51115 11 8
i FOREWORD This report is supplied as part of the " Program for Evaluating Licensee / Applicant Conformance to RG 1.97," Ming conducted for the U.S.
Nuclear Regulatory Commission, Office of Nuclear Reactor Regulation.,
Division of PWR Licensing-A, by EG&G Idaho, Inc., NRR and I&E Support Branch.
The U.S. Nuclear Regulatory Connission funded the work under authorization B&R 20-19-10-11-3.
Occket No. 50-219 TAC No. 51115 111
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CONTENTS A8STRACT....................................'..........................
11 FOREWORD......................k........................................
111
-1.
INTRODUCTION.....................................................
1 2.
REVIEW REQUIREMENTS..............................................
2 3.
EVALUATION.......................................................
4 3.1 Adherence to Regulatory Guide 1.97.........................
4 3.2 Type A Variables...........................................
4 3.3 Exceptions to Regulatory Guide 1.97........................
5 4.
CONCLUSIONS......................................................
16 S.
REFERENCES.......................................................
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CONFORMANCE TO REGULATORY GUIDE 1.97 0YSTER CREEK NUCl. EAR GENERATING STATION j
j 1.
INTRODUCTION i
On December 17, 1982, Generic Letter No. 82-33 (Reference 1) was issued by D. 6. Eisenhut, Director of the Division of Licensing, Nuclear Reactor Regulation, to all licensees of operating reactors, applicants for operating licenses, and holders of construction permits. This letter included additional clarification regarding Regulatory Guide 1.97, Revision 2 (Reference 2), relating to the requirements for emergency response capability.
These requirements have been published as Supplement No. I to NUREG-0737, "TMI Action Plan Requirements" (Reference 3).
GPU Nuclear, the licensee for the Oyster Creek Nuclear Generating Station, provided a response to Section 6.2 of the generic letter on June 13, 1984 (Raference 4). This submittal was superseded by a submittal dated May 9,1986 (Reference 5).
This report provides an evaluation of the material from the May 9, 1986 submittal.
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REVIEW REQUIREMENTS Section 6.2 of NUREG-0737, Supplement No. 1, sets forth the required documentation to be submitted in a report to the NRC describing how the 11censee complies to Regulatory Guide 1.97'as applied to emergency response facilities. The submittal should include documentation that provides the following information for each variable shown in the applicable table of Regulatory Guide 1.97:
1.
Instrument range 2.
Environmental: qualification 3.
Seismic qualification 4.
Quality assurance 5.
Redundance and sensor location 6.
power supply 7.
Location of display 8.
Schedule of installation or upgrade.
The submittal should identify deviations from the regulatory guide and provide supporting justification or alternatives.
Subsequent to the issuance of the generic letter, the NRC held regional meetings in February and March 1983, to answer licensee and applicant questions and concerns regarding the NRC policy on this subject.
At these meetings, it was noted that the NRC review would only address
, exceptions taken to Regulatory Guide 1.97. Where licensees or applicants explicitly state that instrument systems conform to the regulatory guide, it was noted that no further staff review would be necessary. Therefore.
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this report only addresses exceptions to Regulatory Guide 1.97.
The following evaluation is an audit of the licensee's submittals based on the review policy described in the NRC regional meetings.
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EVALUATION 4
The licensee updated their response to Item 6.2 of NRC Generic Letter 82-33 on May 9, 1986. The response describes the licensee's position on post-accident monitoring instrumentation. This evaluation is based on that material.
3.1 Adherence to Reculatory Guide 1.97 The licensee has provided a review of their post-accident monitoring instrumentation that compares the instrumentation characteristics against the recommendations of Regulatory Guide 1.97 Revision 2.
The review compares the provided instrumentation to the instrumentation recommended by the regulatory guide, identifies instrumentation that will be modified to meet the regulatory guide, and gives justification for instrumentation that the licensee has determined appropriate for Oyster Creek. The licensee has scheduled those modifications to be made during either refueling outage 11R or in accordance with the living schedule. Therefore, we conclude that the licensee has provided an explicit commitment on conformance to Regulatory Guide 1.97.
Exceptions to and deviations from the regulatory guide are noted in Section 3.3.
3.2 Tvoe A Variables Regulatory Guide 1.97 does not specifically identify Type A variables, t.e., those variables that provide the information required to permit the control room operator to take specific manually controlled safety actions.
The licensee identifies the following as Type I. variables:
1.
Reactor pressure vessel (RPV) pressure 4
2.
RPV level 3.
Torus water temperature 4
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4.
Torus water level
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5.
Drywell pressure 1
6.
Drywell hydrogen concentration
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Drywell oxygen concentration These variables meet the Category 1 recommendations consistent' wit'h the requirements for Type A variables, except as noted in Section 3.3.
3.3 Exceptions to Reculatory Guide 1.97 The licensee identified deviations and exceptions to Regulatory
- Guide 1.97.
These are discussed in the following paragraphs.
3.3.1 Neutron Flux Regulatory Guide 1.91 recommends Category 1 instrumentation for this
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variable with.a range from 10~0 to 100 percent of full power. Category 1
' recommendations include independent Class 1E power sources. The licensee
'is upgrading their instrumentation with environmentally and seismically qualified source and intermediate range monitors. The average power range monitors (APRMs) are not scheduled to be, upgraded to Category 1.
The licensee also notes that the power source for both redundant channels is derived from the same diesel generator backed bus, with provisions to supply power from the other diesel generator.
.The licensee states that the intermediate range monitors will monitor power levels up to 20 percent of full power, and that monitoring beyond this power level is not needed because the emergency operating precedures that deal with anticipated transients without scram (ATWS) events'.only
, require action if the power level is greater than 2 percent or cannot be determined. As the licensee has not classified this. variable as a Type A variable, we cannot accept this argument as valid. If operator action is
- dependent on this variable it should be a Type A variable. If this is not a 5
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Type A variable, then power levels above the span of the intermediate range monitors may be needed in a post-transient analysis. We conclude that the
.a licensee should upgrade the APRM's to Category 1.
i The licensee's power source for this instrumentation is not i
acceptable. A bus fault could result in the loss of all redundant j
instrumentation, irregardless of the provision to transfer the bus to the alternate diesel generator. This is not in conformance with the single failure criteria. The licensee should provide independent power sources for the redundant instrument channels.
3.3.2 Coolant Level in' Reactor Regulatory Guide 1.97 recommends Category 1 instrumentation for this
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variable with a range from the bottom of the core support plate to the l
centerline of the main steamlines. Category 1 recommendations include independent Class 1E power supplies and redundant channels of instrumentation. The licensee has instrumentation that, with 4 overlapping spans, covers a range from -150 to +180 inches (referenced to the top of active fuel).* One of these spans is covered by a single channel, rather j
.than by redundant channels of instrumentation. No justification was given l
for this deviation. Both redundant sets of instrumentation are powered by the same diesel generator backed source, with provisions to transfer to a power source that is backed up by the other diesel generator.
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- The range limit of -150 inches is equated to 5 1'nches below the bottom of the fuel. We find this acceptable. 'The range limit of +180 inches was defined as 5 inches below the isolation condenser steam lines. It was not related to the centerline of the main steamline or the top of the vessel.
The licensee should provide additional justification for this limit of the range, relating what portions of the range are covered by redundant instrumentation and justifying that portion of the range covered by a single channel.
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The licensee's power source'for this instrumentation is not i
acceptable. A bus fault could result in the loss of all redundant instrumentation, irregardless of the provision to transfer the bus to the alternate diesel generator. This is not in conformance with the single failure criteria. The licensee should provide independent power sources for the redundant instrument channels.
i 3.3.3 Reactor Coolant System Pressure Regulatory Guide 1.97 reconmends redundant power supplies for this i
Instrumentation. The licensee's instrumentation is supplied power by a diesel generator backed power source, with provisions to transfer to a power source that is bac'ked up by the other diesel generator.
The licensee's power source for this instrumentation is not e
acceptable. A bus fault could result in the loss of all redundant i
Instrumentation.,trregardless of the provision to transfer the bus t'o the alternate diesel generator. This is not in conformance with the single failure criteria. The licensee should provide independent power sources for the redundant instrument channels.
3.3.4 Orywell Sumo Level Drywell Orain Sumos Level Regulatory Guide 1.97 reconmends Category 1 instrumentation for these variables. The sumps at Oyster Creek use level switches to alarm in the control room and to initiate sump pump out. Timers indicate the duration of sump pump operation for estimating the amounts of leakage.; No safety-related system is actuated either automatically or manually as a result of the sump level. The drywell sump systems are automatically isolated at the primary containment penetration should an, accident occur.
Drywell temperature and pressure, and primary containment area radiation l
instrumentation, also can be used to show leakage from the reactor coolant l
' system.
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h We conclude that the alternate instrumentation provided by the er licensee will prov13e the appropriate monitoring for the parameters of concern. This is based on (a) for small leak's, the alternate instrumentation is not expected to experience harsh environments during operation, (b) for larger leaks, the sumps fill promptly and the sump drain lines isolate due to the increase in drywell pressure, thus negating the drywell sump level and drywell drain sumps level instrumentation, (c) the drywell pressure and temperature as well as the primary containment area radiation instrumentation can be used to detect leakage in the drywell, and (d) this instrumentation neither automatically initiates nor alerts the operator to initiate operation of a safety-related system in a post-accident situation.. Therefore, we find the alternate Category 3 instrumentation provided acceptable.
3.3.5 Radiation Level in Circulatino Primary Coolant The licensee indicates that the following instruments are prov1ded to indicate the failure of fuel cladding.
1.
Condenser off-gas radiation instrumentation.
2.
Main steamline radiation instrumentation, 3.
Primary containment radiation instrumentation, 4.
Containment hydrogen concentration instrumentation, and S.
Post-accident sampling system.
i The post-accident sampling system is being reviewed by the NRC as part of-their review of NUREG-0737, Item 11.8.3.
, The licensee indicates that only shutting down the reactor and
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maintaining the coolant level are required in a post-accident situation.
The instrumentation for this variable does not assist in either action.
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' Based on the alternate instrumentation and the justification provided
'by the licensee, we conclude that the instrumentation supplied for this variable is adequate and, therefore, acceptable.
3.3.6 Containment Effluent Radioactivity Effluent Radioactivity Regulatory Guide 1.97 recomends the following instrumentation for these variables. For containment effluent radioactivity, Category 3 instrumentation with a range of 10-0 to 10-2 pC1/cc is reconnended.
For effluent radioactivity, Category 2 instrumentation with a range of 10-6 to 10 pC1/cc is recommended. The licensee has shown that this 3
instrumentation, which because of plant design is the same for both l
variables, is Category 2 except for the power supply. The licensee should I
show that the power for this instrumentation is suitable for Category 2 ins'trumentation.
The licensee states that the range of 10-6 to 10-2 wC1/cc has not been confirmed by calibration. The licensee says that the principal purpose of th,is instrumentation is to actuate the Standby Gas Treatment System. We find the range deviation unacceptable. The Itcensee should show the range of the instrumentation is sufficient to meet the purpost of this instrumentation as listed in Regulatory Guide 1.97.
3.3.7 Radiation Exoosure Rate Regulatory Guide 1.97, Revision 2, recommends Category 2 4
instrumentation for this variable with a range of 10~I to 10 R/hr.
The licensee's instrumentation is Category 3.
The ranges are not identified by the licensee. As Revision 3 of the regulatory guide changes the recommendation to Category 3, we find the instrumentation acceptable, except for the range.
The licensee states that rather, than using an arbitrary limit of 4
10 R/hr, they will, on a case by case basis, address the worst case expected radiation level for a given instrument's location. Should 9
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.c post-accident access by necessary, the licensee states that the installed sensors will be used in combination with portable survey instruments and sampling. The licensee has not submitted an ' analysis of the radiation levels expected for the monitor locations. The licensee should identify the instrumentation location and ranges, consistent with the requirements of Section 6.2'of NUREG-0737, Supplement No. 1, and show that the existing radiation exposure rate monitors have ranges that encompass the expected radiation levels in their location.
I 3.3.8 Suppression Pool Soray Flow Drywell Soray Flow The containment spray system flow instrumentation is used for both of these variables. Both the suppression pool and the drywell spr.ays are portions of the containment spray flow sytem, which is monitored in the control room by Category 2 instrumentation. A throttling valve proportions the flow between.the two sprays. While there is indication of the position
'of this valve in the control room, the licensee has not shown it to be Category 2.
Pressure and temperature changes in the drywell and torus determine the effectiveness of the spray. The licensee concludes that the containment spray flow, the torus and drywell temperature and pressure and the throttling valve position indication, accurately and reliably measure the effectiveness of the drywell and suppression chamber spray.
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We find that this instrumentation will provide the flow indication for these variables, however, the licensee should verify that the position l
indication of the throttling valve is Category 2 instrumentation.,
l 3.3.9 Torus Water Temperature I
, The licensee has classified this as a Type A variable; as such, the instrumentation should be Category 1, The licensee has identified 4 channels of instrumentation that are powered by the same diesel generator backed source, with capability to transfer to the other diesel generator.
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The licensee has also identified a common recorder for all 4 channels. The licensee states that redundant and separate environmentally qualified channels will be provided. Details were not 'provided.
The licensee's power source for this instrumentation is not acceptable. A bus fault could result in the loss of all redundant instrumentation, irregardless of the provision to transfer the bus to the alternate diesel generator. This is not in conformance with the single failure criteria. The licensee should provide independent power sources for the redundant instrument channels.
The licensee should describe the modified instrumentation in sufficient detail to show that the criteria for Category 1 instrumentation are satisfied.
3.3.10 Standby Liouid Control System Flow The licensee has elected not to implement this variable as recommended by Regulatory Guide 1.97. The justification given by the licensee is that the standby liquid control system (SLCS) pump discharge pressure provides indication that the SLCS. pump is operating and that the level indication in the SLCS storage tank gives indication that flow is occurring.
In addition, the following instrumentation supplements the above':
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Neutron flux l
2.
Pump motor indicating lights,
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Squib valve continuity indicating lights.
We find the above instrumentation valid as an alternative indication of SLCS flow.
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m 3.3.11 Standby Liauid Control System Storace Tank Level Regulatory Guide 1.97 recommends Category 2 instrumentation for this variable. The licensee has Category 3 instrumentation, and uses it as a key variable in determining that standby liquid control system (SLCS) flow is occurring.
The licensee states that this instrumentation will be operating in a mild environment and that the current design basis for the SLCS recognizes that the system has a classification less than the importance to safety of the reactor protection system and the engineered safeguards systems.
The instrumentation is stated to be in a mild environment, however, the licensee has not verified that the level instrumentation is Category 2.
The licensee should verify that this instrumentation is Category 2.
3.3.12 Coolina Water Temperature to Encineered Safety Features System Components The licensee has not provided instrumentation for this variable which is' defined by the licensee as emergency service water temperature to tte i
containment spray heat exchanger. The licensee states that proper operation of the heat exchanger for the containment' spray system is observed by the containacat spray system
- flow (which is Category 2 instrumentation) and heat exchanger inlet and outlet temperature (which the.
licensee has not identified as Category 2 instrumentation).
We find this instrumention acceptable for this variable; however, the licensee should verify that the temperature instrumentation is Category 2.
Additionally, the licensee should verify that the containment spray system is the'only engineered safety feature that utilizes cooling water.
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3.3.13 Hiah Radioactivity L1 auld Tank Level
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Regulatory Guide 1.97 recommends a reado'ut for this instrumentation in.
1 the main control room. The licensee's instrumentation does not have a readoutthere,butisindicatedlintheradwestecontrolroom. The licensee -
states that this information can be relayed to the main control room by the use of telephones or radio links. This infers that the radweste control i
l room is habitable and manned following an accident.
Based on the licensee's justification, we find that monitoring this variable in the main control room of the Oyster Creek Station is not necessary.
i 3.3.14 Status of Standby power-Regulatory Guide 1.97 recommends Category 2 instrumentation for,this variable. The licensee's instrumentation is Category 3.
No justification was given for this deviation.
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We conclude that the licensee should upgrade this instrumentation to Category 2.
3.3.15 Reactor Buildina Area Radiation Regulatory Guide '1.97 recommends Category 2 instrumentation for this variable with a range of 10~I to 10* R/hr. The licensee states that this variable need not be implemented.,The licensee reports that the use I
of local radiation exposure rate monitors to detect breach or leakage through primary containment penetrations results in ambiguous indications.
This is due to the radioactivity in the primary containment, the
' radioactivity in the fluids flowing in emergency core coolant system piping and the amount and the location,of fluid and electrical penetrations. The 1icensee concludes that the use'of the vent stack noble gas offluent monitors is the proper way to accomplish the detection of releases, release 13
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h' assessment and the long term surveillance recommended for this variable.
U l,I The license has not shown that the vent stack noble gas effluent monitors cover the rangs recommended for this variable'.
We find the licensee's use of the alternative vent stack noble gas effluent monitors, in principle, to be acceptable. However, the licensee should show that the vent stack noble gas effluent monitors cover the I
4 equivalent to the recomended 10 to 10 R/hr range.
3.3.16 Stack Noble Gas and Vent Flow Rate Regulatory Guide 1.97 recommends Category 2 instrumentation for this variable with ranges of'10 to 10* yC1/cc (because of the drywell or standby gas treatment system purge being included) and 0 to 110 percent of design flow.
The licensee has noted the following deviations:
1.
The equipment is not environmentally qualified; however, it is located in a mild environment. Therefore, environmental qualification is not required per 10 CFR 50.49.
2.
The licensee,has not verified the use of a h'igh reliability power source for this instrumentation. No justification was given.
The licensee should provide a highly reliable power source for this instrumentation.
3.
The licensee notes that they do not meet the recomended range 4
limit of 10 pC1/cc. No justification was provided. The range limit of the instrumentation provided was not identified.
Therefore, we conclude that the licensee should either provide the recommended range or identify the provided range and provide
' acceptable justification for the deviation.
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3.3.17 Accident Samo11no (Reactor Coolant. Containment Air and Sumost The licensee's post-accident sampling system can obtain samples and provide the analyses within the ranges recommended for this variable from
- the reactor coolant and the containment air. The licensee does not sample the containment, auxiliary building or emergency core ' coolant system (ECCS) sumps as recommended by Regulatory Guide 1.97. The torus and reactor coolant are sampled. The drywell sump systems overflow to the torus.
The licensee deviates from Regulatory Guide 1.97 with respect to Post-accident sampling capability. This deviation goes beyond the scope of this review and is being reviewed by the NRC as part of the review of NUREG-0737. Item II.8.3.'
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CONCLUSIONS Based on our review, we find that the licensee either conforms to or isjustifiedindeviatdyrfromRegulatoryGuidet.97,withthefollowing
- exceptions:
1.
Neutron flux--the licensee should upgrade the average power range monitors to Category 1; the licensee should provide independent Class 1E power supplies for the redundant channels of instrumentation (Section 3.3.1).
2.
Coolant level,in reactor--the licensee should provide additional information on the range and the span that is covered by a single channel; the licensee should provide independent Class 1E power supplies for the redundant channels of instrumentation (Section 3.3.2).
3.
Reactor coolant system pressure--the licensee should provide independent Class 1E power supplies for the redundant channels of instrumentation (Section 3.3.3).
4.
Containment effluent radioactivity--the licensee should show.that the range of this instrumentation is adequate for its purpose as listed in the regulatory guide.(Section 3.3.6).,
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Effluent radioactivity--the licensee should vuify that the power supply is suitable for Category 2 instrumentation; the licensee should show that the range of this instrumentation is adequate for its purpose as listed in the regulatory guide (Section 3.3.6).
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Radiation exposure rate--the licensee should show, by analysis, that the instrumer.t rar:ge for a given location encompasses the maximum expected radiation level (Section 3.3.7).
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Containment spray throttling valve position--the licensee should h{-
verify that this instrumentation is Category 2 (Section 3.3.8).
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Torus water temperature--the licensee should provide independent Class 1E power supplies and show that the Category 1 criteria are satisfied for this instrumentation (Section 3.3.9).
9.
Standby liquid control system storage tank level--the licensee should verify that this instrumentation is Category 2 (Section 3.3.11).
- 10. Cooling water temperature to engineered safety features system components--th'e licensee should verify that the containment spray heat exchanger inlet and outlet temperature instrumentation is Category 2, and verify that the containment spray system is the only engineered safety feature that utilizes cooling water (Section 3.3.12).
- 11. Status of standby power--the licensee should upgrade this instrumentation to Category 2 (Section 3.3.14).
- 12. Reactor building area radiation--the licensee should provide,
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additional justification for the exception of instrumentation for this variable (Section 3.3.15).
- 13. Stack noble gas and vent flow rate--the licensee should provide a highly reliable power source for this instrumentation.
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REFERENCES a
1.
NRC letter, D. G. Eisenhut to All Licensees of Operating Reactors.
Applicants.8or Operating Licenses, and Holders of Construction Permits.* Supplement No. 1 to NUREG-0737--Requirements for Emergency Response Capability (Generic Letter No. 82-33) " December 17, 1982.
2.,
Instrumentation for Licht-Water-Cooled Nuc100r Power Plan",s to Assess Plant and Environs Condit, tons Durina and Fo'
' owino an Acc' dent, Regulatory Guide 1.97, Revision 2, NRC, Office of Standards Development, December 1980.
3.
Clarification of TNI Action Plan Reauirements. Recuirements for imeraency Response Capability, NUREG-0737, Supplement No. 1, NRC, Office of Nuclear Reactor Regulation, January 1983.
4.
GPU Nuclear letter, P. 8. Fiedler to D. G. Eisenhut, NRC,
" Supplement 1 to NUREG-0737 Regulatory Guide 1.97 Response," June 13, 1984.
5.
GPU Nuclear letter, P. 8. Fiedler to J. A. Zwolinski, NRCf
" Supplement 1 to NUREG-0737 Regulatory Guide i.97 Response,"
May 9, 1986.
6.
Instrumentation for Licht-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions Durina and Fol'owina an Accident, Regulatory Guide 1.97, Revision 3, NRC, Office of Nuclear Regulatory Research, May 1983.
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