ML20063E059
| ML20063E059 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 02/03/1994 |
| From: | Mccoy C GEORGIA POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20063E061 | List: |
| References | |
| LCV-0202, LCV-202, NUDOCS 9402090057 | |
| Download: ML20063E059 (11) | |
Text
- Geoga Power Company 40 inmmess Cons Pmeway Pwi.0%ce Box 12 %
, ihme-@yR Aytarna 35201 Teephone 205 877 712' m.
C. K. McCoy Georuia v
Power ya, n+ < a . tp&w vge vn.o n w ~newancuswn Docket Nos. 50-424 50-425 U. S. Nuclear Regulatory Conunission ATTN: Document Control Desk Washington, D. C. 20555 Gentlemen:
VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS RELATED TO AREA TEMPERATURE MONITORING n
In accordance with the provisions of 10 CFR 50.90 and 10 CFR 50.59, Georgia Power Company (GPC) hereby proposes to amend the Vogtle Electric Generating Plant (VEGP)
Unit I and Unit 2 Technical Specifications (TS), Appendix A to Operating Licenses NPF-68 and NPF-81. This proposed change will relocate the requirements olTS 3/4.7.10, Area Temperature Monitoring, to section 16.3 of the VEGP Final Safety Analysis Report (FSAR). With this relocation to the FSAR, GPC plans to clarity the basis for areas to be monitored and modify these surveillance requirements. This change is being proposed in accordance with NUREG-1431, " Standard Technical Specifications, Westinghouse Plants."
During the initial licensing of VEGP Units I and 2, GPC committed to monitoring the temperature of rooms containing safety related equipment necessary for safe shutdown that are not served by engineered safety feature ventilation systems and do not have temperature monitors. This was based on a concern that during the course of normal operations the temperature might exceed the values that were used as the basis of equipment environmental qualification. The basis and purpose of the area temperature monitoring program were not included in the FSAR. Therefore, additional information will be added to FSAR section 3.11.B in conjunction with this request for Technical Specification revision, which will explain the purpose of the area temperature monitoring program and the basis for the selection of rooms to monitor.
In accordance with the current Technical Specification, the temperatures in the specified rooms have been monitored at least twice per day, and as a result, a considerable amount ofinformation has been gained concerning the stability of the temperatures in these rooms. 1 This experience has shown that temperatures generally remain within design limits. .i P 9402090057 940203 I
- PDR ADOCK 05000424 F {/
P PDR 1 l
\--. .
a 4 G..eorgia Power h(
U. S. Nuclear Regulatory Commission Page 2 Therefore, GPC is revising the basis for the area temperature monitoring program, as presented in the proposed FSAR section included with this TS request for revision, to be consistent with the design and operating experience of the plant. Georgia Power Company requests that this revision to the Technical Specifications be approved by -
June 1,1994.
The proposed change and the bases for the change are described in enclosure 1 to this letter. Enclosure 2 provides an evaluation pursuant to 10 CFR 50.92 showing that the proposed change does not involve significant hazards considerations. Instructions for the incorporation of the proposed change to the technical specifications and a copy of the change are provided in enclosure 3. Enclosure 4 contains the applicable FSAR revisions describing the requirements being relocated to the FSAR and their bases.
In accordance with 10 CFR 50.91, the designated state official will be sent a copy of this ,
letter and all enclosures. '
Mr. C. K. McCoy states that he is a vice president of Georgia Power Company and is authorized to execute this oath on behalf of Georgia power company and that, to the best of his knowledge and belief, the facts set forth in this letter and enclosures are true.
GEORGIA POWER COMPANY By:
C. K. McCoy /
v Sworn to and subscribed before me thisi- rbday of ffh/'nMIL.1994. l d
' / d rut y 'f L [ w d k Notarypublic vywunawnw MkWh 4.
.h9 CKM/AFS LCV- 0202 mm
l
,. . l Georgia Power Jo. k ;
i U. S. Nuclear Regulatory Commission Page 3
Enclosures:
- 1. Basis for Proposed Change -
- 2. 10 CFR 50.92 Evaluation .
- 3. Instructions for Change and Revised Pages
Mr. M. Sheibani -
NORMS U. S. Nuclear Reuulatory Commission Mr. S. D. Ebneter, Regional Administrator Mr. D. S. Hood, Licensing Project Manager, NRR Mr. B. R. Bonser, Senior Resident Inspector, Vogtle r
Slate ofGegrgi_a Mr. J. D. Tanner, Commissioner, Dept. ofNatural Resources i
l l
LCV- 0202 i
700775
i 1
!' ENCLOSURE 1 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS RELATED TO AREA TEMPERATURE MONITORING BASIS FOR PROPOSED CHANGE l Proposed Change ,
The proposed change to the Vogtle Electric Generating Plant (VEGP) Unit I and Unit 2 Technical Specifications (TS) would relocate the requirements ofTS 3/4 .7.10, Area l Temperature Monitoring, to sections 3.11 and 16.3 of the VEGP Final Safety Analysis j Report (FSAR). j i
BMs i On July 22,1993, the Final Policy Statement on Technical Specifications Improvements for Nuclear Power Reactors became effective. According to the Policy Statement, the purpose of the TS is to impose those conditions or limitations upon reactor operation necessary to prevent the possibility of an abnormal situation or event giving rise to an immediate threat to the public health and safety by identifying those features that are of controlling importance to safety and establishing on them certain conditions' of operation which cannot be changed without prior Commission approval. Furthermore, the Policy -
Statement establishes an objective set of criteria which delineate those constraints on design and operation of nuclear power plants that are derived from the FSAR and that belong in the TS in accordance with 10 CFR 50.36 and the purpose of the TS.
I Specifically, these criteria are as follows:
e Installed instmmentation that is used to detect, and indicate in the control room, a significant abnormal degradation of the reactor coolant pressure boundary.
-I e A process variable, design feature, or operating restriction that is an initial condition of a design basis accident or transient analysis that either assumes the failure of or presents a :hallenge to the integrity of a fission product barrier.-
- A structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of, or presents a challenge to, the integrity of a fission product barrier.
- A structure, system, or component which operating experience or probabilistic -
safety assessment has shown to be significant to public health and safety.
El-1
i l
i ENCLOSURE 1 (CONTINUED)
REQUEST TO REVISE TECHNICAL SPECIFICATIONS RELATED TO AREA TEMPERATURE MONITORING l BASIS FOR PROPOSED CHANGE The purpose of the area temperature monitoring program described in the Technical Specifications is to assure safety related equipment necessary for safe shutdown, and not serviced by engineered safety feature (ESF) heating, ventilation, and air conditioning (IIVAC) systems, will not be subjected to temperatures in excess ofits environmental qualification and therefore remain operable in order to perform its intended safety function. However, the only parameter being monitored in compliance with this TS smveillance requirement is area temperature, which gives no direct indication of a specific equipment's operability status but of an HVAC malfunction or misoperation. .Nor is this i temperature surveillance used to detect or indicate in the control room a significant abnormal degradation of the reactor coolant pressure boundary. Similarly, the area temperature monitoring program does not yield a process variable that is an initial condition of a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier. Furthermore, the area temperature monitoring program is not a structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of, or presents a challenge to, the integrity of a fission product barrier.
Finally, with respect to probabilistic risk significance, the existing area temperature monitoring TS requirements are not risk dominant based on the core melt and health effects screening given in Section 2-D of WCAP-11618, " Methodically Engineered, Restructured, and Improved Technical Specifications," MERITS Program- Phase II, Task 5, Criteria Application. Probability Risk Analysis (PRA) studies performed to date .
do not explicitly model the function of area temperature monitors. In many cases, a reasonable amount ofinstrument error would not compromise the ability of the operator or automatic systems to correctly diagnose the accident and take appropriate action.
Also, area temperature monitoring has not been shown to be of prime importance in limiting the likelihood or severity of the accident sequences that are commonly found to dominate risk.
This relocation of the area temperature monitoring requirements into the FSAR will continue to assure that area temperatures are controlled. Any future changes to the program will be made under the provisions of 10 CFR 50.59, which will assure that they' do not involve any unreviewed safety questions. In addition, the requirements to be placed ;
in FSAR section 163 will be controlled in accordance with Technical Specification 6.7.1.i.
El-2 ,
4 ENCLOSURE I (CONTINUED)
REQUEST TO REVISE TECHNICAL SPECIFICATIONS RELATED TO AREA TEMPERATURE MONITORING BASIS FOR PROPOSED CHANGE In conclusion, the existing TS requirements for the area temperature monitoring program do not meet any of the criteria of the Final Policy Statement and can safely be relocated to the VEGP FSAR. This conclusion is consistent with the results of the NRC review of the application of the Interim Policy Statement criteria to the Westinghouse Standard Technical Specifications as documented in NRC letter, T. E. Murley to W.S. Wilgus, "NRC Staff Review of Nuclear Steam Supply System Vendor Owners Groups' Application of the Commission's Interim Policy Statement Criteria to Standard Technical ,
Specifications," May,1988.
I l
El-3 l
2 e w
i
, ', l ENCLOSURE 2 VOGTLE ELECTRIC GENERATING PLANT 1 REQUEST TO REVISE TECHNICAL SPECIFICATIONS l RELATED TO AREA TEMPERATURE MONITORING 10 CFR 50.92 EVALUATION Pursuant to 10 CFR 50.92, Georgia Power Company (GPC) has evaluated the proposed ,
revision to the Technical Specifications (TS) and has determined that operation of the facility in accordance with the proposed amendment would not involve any significant hazards considerations.
Background
During the initial licensing of VLM , the NRC and GPC conducted an extensive review of equipment qualifications. Much of the effort was to confirm that the environmental ,
conditions under which the equipment would be expected to perform its safety function are consistent with the qualification of the equipment. As a result of these efforts, GPC agreed to monitor certain rooms containing safety related equipment that are not provided with safety related ventilation systems or temperature monitoring instrumentation. This list of rooms is currently included in Technical Specification 3/4.7.10. The current Technical Specification requires verification at least once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> that the rooms identified for area temperature monitoring are within their temperature limits. These temperature monitoring activities have continued from initial plant operation to the present. Based on the information gained from this monitoring, GPC has concluded that the normal ventilation systems provide adequate cooling capability to maintain room temperatures below the normal qualification design temperature limits. Therefore, in addition to moving this Technical Specification to the FSAR, GPC proposes that this surveillance be performed only when the normal ventilation systems are not in service.
Since the original implementation of this specification, GPC has revised the bases for qualification of equipment in mild environments. Therefore, GPC also proposes to revise the screening criteria in order to account for mild environments when determining the rooms included in the area temperature monitoring program. Furthermore, since excessive temperatures will continue to be evaluated for the effects on equipment operability, GPC proposes to eliminate the requirement for specific reporting based on excessive temperature in favor of the existing Technical Specifications for operability.
Analysis The purpose of area temperature monitoring is to provide reasonable assurance that the normal operating temperatures in the selected rooms will remain consistent with the )
temperatures assumed for the environmental qualification of safety related equipment.
E2-1 l
1 L i
ENCLOSURE 2 (CONTINUED)
REQUEST TO REVISE TECHNICAL SPECIFICATIONS RELATED TO AREA TEMPERATURE MONITORING 10 CFR 50.92 EVALUATION The normal operating temperature is significant for its effect on the qualified life of the components as well as the predicted environmental transients (i.e., pressure, temperature, and radiation) that occur under accident conditions. The followingjustifications are provided for the proposed changes to the area temperature monitoring program:
- 1. The proposed change to perform temperature surveillances only when the normal ventilation system is out of service is justified based on the following:
- a. The HVAC systems at VEGP have been designed to maintain the room temperatures at less than the maximum normal temperature specified for environmental qualification purposes. The HVAC calculations have conservatively considered the worst case heat load conditions with a nominal safety factor when sizing the cooling systems that serve the subject rooms. As a result, the plant is generally maintained at temperatures well below the level assumed for normal operation and used for environmental qualification of equipment.
- b. Temperature monitoring activities per Technical Specification 3/4.7.10 have been in place for 6 years on Unit I and 4 years on Unit 2. The data collected during this time demonstrate that the temperatures have remained well within environmental qualification limits with the exception of the main steam isolation valve (MSIV) area which has exceeded its reportability limits on several occasions. The MSIV area has since been provided with a new ventilation system and temperature monitoring instrumentation.
When the normal ventilation system for one of the specified rooms is not functioning, temperature monitoring activities will resume at the previously specified rate of once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The proposed change to monitor these rooms only when the normal ventilation system is out of service will provide a level of assurance that is similar to that provided by the current Technical Specification. Therefore, continued monitoring is not warranted as long as the normal ventilation systems are functioning.
- 2. The proposed change in room selection criteria to eliminate rooms that are classified as mild environment isjustified based on the current methods of environmental qualification. The qualified life of safety related equipment in a mild environment is no E2-2 a
. ,.*+.
ENCLOSURE 2 (CONTINUED)
REQUEST TO REVISE TECHNICAL SPECIFICATIONS RELATED TO AREA TEMPERATURE MONITORING 10 CFR 50.92 EVALUATION longer based on environmental qualification, but is based on a combination of design life, trending, and periodic maintenance and surveillance as discussed in FSAR section 3.11.B. Therefore, the monitoring of mild rooms is not required to verify that the normal design temperature is being maintained. However, the existing Technical Specifiestions not only require monitoring of the normal room temperature, but also require actions to evaluate equipment operability if an abnormal condition temperature limit is exceeded.
To address this abnormal temperature condition, the rooms that are not monitored based on mild environment will not exceed 150 F following a complete loss of normal HVAC for a 7-day period 1. The abnormal temperature limits currently shown in the Technical Specifications are the calculated room temperatures with a loss of normal HVAC for a 24-hour period. The new criterion is based on an equipment qualification analysis that demonstrates that short duration temperature excursions of up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> at 150 F have .m insignificant effect on the qualified life of electrical and mechanical equipment. This limitation is further supported by Appendix F of NUMARC Report 87-00 that concludes that electrical and mechanical equipment will operate in station blackout conditions with no loss of function with temperatures of up to 150 F for short durations (i.e.,4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />)._
- 3. Relocation of area temperature monitoring to the FSAR and the revision of the TS reporting requirements are justified as follows:
- a. As discussed in enclosure 1, the existing TS requirements for the area temperature monitoring program do not meet any of the criteria of the Final Policy Statement -
on Technical Specification Improvements for Nuclear Power Reactors and can ;
safely be relocated to the FSAR.
E2-3 i l
l 1
1 Per project calculations, the loss of normal HVAC for 7 days has been shown to be sufficient time to I achieve steady state temperature conditions.
l
l
'. )
ENCLOSURE 2 (CONTINUED)
REQUEST TO REVISE TECHNICAL SPECIFICATIONS RELATED TO AREA TEMPERATURE MONITORING 10 CFR 50.92 FJALUATION
- b. The area temperature monitoring program added to the FSAR will continue to ,
ensure that room temperatures are maintained within the limits assumed for environmental qualification. The monitoring requirements of once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> when the nonnal ventilation system is not in service will ensure that a room would not experience a short duration temperature excursion for more than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> without an evaluation ofequipment operability. Although reporting requirements have been excluded from the FSAR description, an evaluation of equipment operability will continue to be performed in the event that the temperature limits are exceeded. The reporting of operability concerns to the NRC will be based on the reporting requirements for the specific equipment in an affected area afler a a determination of operability has been made. The current TS requires that a report ,
be prepared and submitted to the NRC that demonstrates the continued operability of the affected equipment if the maximum normal temperature in an area is exceeded for more than 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The new FSAR description will continue to require an evaluation of equipment operability if either the normal temperature limit or abnonnal condition temperature limit is exceeded. However, no report to the NRC will be required unless the equipment operability evaluation indicates a ,
reportable condition.
Dmlusion Based on the above considerations, GPC has concluded the following concerning '
- l. The proposed change to the Technical Specifications does not involve a significant increase in the probability or consequences of an accident previously evaluated. The environmental qualification and operability of the safety related equipment will not be adversely affected by the proposed changes to the area temperature monitoring program. The relocation ofTS to the FSAR and the changes to monitoring frequency will not increase the probability that the room temperature design limits will be exceeded or result in a loss of qualified life of safety related equipment. In addition, ,
the consequences of exceeding the temperature limits will not significantly differ from i the existing program since an evaluation of qualified life and operability will continue to be performed.
E2-4 j
ENCLOSURE 2 (CONTINUED) e REQUEST TO REVISE TECHNICAL SPECIFICATIONS RELATED TO AREA TEMPERATURE MONITORING 10 CFR 50.92 EVALUATION
- 2. The proposed change to the Technical Specifications does not create the possibility of ;
a new or different kind of accident from any accident previously evaluated. The ,
relocation of area temperature monitoring to the FSAR and the changes in monitoring procedures do not change the design ofindividual equipment, systems, nor the plant operating procedures and therefore will not create the possibility of a new or different .,
kind of accident from those already evaluated. ;
- 3. The proposed change to the Technical Specifications does not involve a significant reduction in the margin of safety because the revised monitoring requirements will continue to ensure that the environmental qualification temperature limits of safety .
related equipment scoped in the area temperature monitoring program will not be '
exceeded without an evaluation of equipment operability.
Based upon the preceding information, it has been determined that the proposed Technical Specifications change does not involve a significant ha7Cds consideration as defined by 10 CFR 50.92.
4 E2-5 :
1 i