ML18046B175
| ML18046B175 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 12/18/1981 |
| From: | Crutchfield D Office of Nuclear Reactor Regulation |
| To: | Hoffman D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| Shared Package | |
| ML18046B116 | List: |
| References | |
| TASK-03-06, TASK-03-11, TASK-3-11, TASK-3-6, TASK-RR LSO5-81-12-058, LSO5-81-12-58, NUDOCS 8112290312 | |
| Download: ML18046B175 (21) | |
Text
*.
December 18, 1 981 Docket No. 50-255 LS05-8l-12-058 Mr. David P. Hoffman Nuclear Licensing Administrator Consumers Power Company 212 West Michigan Avenue Jackson, Michigan 49201
Dear Mr. Hoffman:
SUBJECT:
SEP SAFETY TOPICS III-6, SEISMIC DESIGN CONSIDERATION, AND III-11~ COMPONENT INTEGRITY - PALISADES NUCLEAR POWER PLANT He have completed our seismic review of Palisades Nuclear Power Plant.
Enclosed is a copy of our draft combined evaluation report of the two subj~tt topics~ -
As discussed in this draft report, some equipment items still remain open due to lack of design information. According to mutual agreement between the staff and your representative, the responses to these open items are scheduled by December 22, 1981.
A,_S!,J_l?J?JJ~_l!!gil:t_to_tt:ii~--~\\f-~ll!:_. ___ ~----------------~--
ation report will be issued after the review1of your responses is completed.
j
~-~- -___ *-~~
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__, ---~--"' __..,-'..**.'.-i:t-~--~.~- ---~---~---~~.,_ ____ i You are requested to examine the facts upon which the staff has based its evaluation and respond either by confirming that the facts are correct, or by identifying errors and supplying the corrected information.
We encourage you to supply any other material that might affect the staff's evaluation of these topics or be significant in the integrated assessment of your facility.
of receipt of this letter. If we will assume that you have no Your response is requested within 30 days no response is received within that time, comments or corrections.
- s~oc/
Enclosure:
As stated Sincerely,..
Dennis M. Crutchfield, Chief Operating Reactors Branch No. 5 Division of licensing
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- 7. f"/\\.r:~1:/1 jUSGfO: 1_961-335-960 I
v Mr. David P. Hoffman cc M. I. Miller, Esquire Isham, Lincoln & Beale Suite 4200 One First National Plaza Chicago, Illinois 60670 Mr. Paul A. Perry, Secretary Consumers Power Company 212 West Michigan Avenue Jackson, Michigan 49201 Judd L. Bacon, Esquire Consumers Power Company 212 West Michigan Avenue Jackson, Michigan 49201 Myron M. Cherry, Esquire Suite 4501 One IBM Plaza Chicago, Illinois 60611 Ms. Mary P. Sinclair Great Lakes Energy Alliance 5711 Summerset Ori ve Midland, Michigan 48640 Kalamazoo Public Library 315 South Rose Street Kalamazoo, Michigan 49006 Township Supervisor Covert Township Route 1, Bo~ 10 Van Buren County, Michigan Office of the Governor (2)
Room l - Capitol Building Lansing, Michigan 48913 William J. Scanlon, Esquire 2034 Pauline Boulevard Ann Arbor, Michigan 48103 Palisades Plant ATTN~ Mr. Robert Montross Plant Manager Covert, Michigan 49043 49043 PALISADES Docket No. 50-255 U. S. Environmental Protection Agency Federal Activities Branch Region V Office ATTN:
EIS COORDINATOR 230 South Dearborn Street
- Chicago, Illinois 60604 Charles Bechhoefer, Esq., Chairman Atomic Safety and Licensing Board Panel U. S. Nuclear Regulatory Commission Washington, D. C.
20555 Dr. George C. Anderson Department of Oceanography University of Washington Seattle, Washirigton 98195 Dr. M. Stanley Livingston 1005 Calle Largo Santa Fe, New Mexico 87501 Resident Inspector
.c/o U. S. NRC Palisades Plant Route 2, P. O. Box 155 Covert, Michigan 49043
SEP SAFETY*TOPIC EVALUATION PALISADES NUCLEAR POWER PLANT TOPICS:* III-6.
- SEISMIC DESIGN *CONSIBERAHON III-11 *. COMPONENT INTEG~ITY INTRODUCTION The nuclear power plant facilities under review in the SEP received construction permits between 1956 and 1967.*
Seismic design.procedures evolved significantly during and after this period. The Standard Review Plan (SRP) first issued in 1975. along with the Regulations 10 CFR Part so. Appendix A and 10 CFR Part 100.
Appendix A constitute current licensing criteria for seismic design reviews.
As a result. the original seismic design of the SEP facilities vary in degree from the Uniform Builing Code up through and approaching current standards. Recognizing this evolution. the staff found that it is necessary to make a reassessment of of the seismic safety of these plants.
Under SEP seismic reevaluation. these eleven plants were categorized into two groups based upon the ori gi na l seismic design and the avai 1 ability of seismic design documentation.
Different approaches were used to review the plant facili-ties in each group~ The approaches were:
Group I:
Detailed NRC review of existing seismic design documents with limited reevaluation of the existing facility to confirm judg-ments on the adequacy of original design with respect to current requirements *.
- Group II: Licensees were required to reanalyze their facilities and to upgrade. if necessary. the seismic capacity of their facility.
REGULA JORY DOC.KET FILE COPY
- - 2' -
The staff will review the licensee 1s reanalysis methods~ scope, and results. Limited independent NRC analysis will be perf_ormed
.to confirm the adequacy of the licensee 1s method and results.
Based upon the staff 1s assessment of the original seismic design; the Palisades plant was placed in Group I for review.
The Palisades plant, a pressurized lightwater moderated and cooled nuclear reactor,*
is located on the eastern shore of Lake Michigan, about 16 miles north of Benton Harbor, Michigan.
Combustion Engineering, Inc. supplied the nuclear steam supply system and Bechtel Power Company was the architect-engineer and general contractor.
The plant received_ its construction permit on March 13, 1967 and provisional operating license on March 24, 1971. The Consume.rs Power Company (CPCo),, the owner, filed its application for a full-term operating license on January 22, 1974.
The Palisades plant was originally designed for an operating basis earthquake (OBE).
with a peak ground acceleration (PGA) of O.lg and for a safe shutdown earthquake (SSE) with a PGA of 0.2g.
Housner ground.response spectra scaled to the specified PGAs were used as seismic input for th~ analyses and design.
The vertical component of ground motion was assumed to be two:..thirds of the horizontal components.
For the dynamic analyses of structures (containment building, turbine building, and auxiliary building), the buildings were modelled as lumped mass-spring systems with soil springs attached at foundation mat to.account for the soil-structure interaction effects; re-sponse spectrum analysis approach was applied to generate member forces for the struc-tural design.
Two methods were used for the analysis of safety related piping systems and equipment:
(1) the response spectrum analysis approach with floor response spectra generated from the 1952 Taft earthquake record as input motion, and (2) the equivalent static method using peak structural responses as input.
The damping ratios recommended b
le
.88 Housner were the damping valL1es used for structural and system analyses.
Chapter 4 of NRG NUREG/CR-1833 report.
11Seismic Review of the Palisades Nuclear Power Plant Unit 1 as Part of the Systematic Evaluation Program 11 (ref. l)J summarizes the details of the original* analysis and design.
The SEP seismic review of.Palisades facilities addressed only the Safe Shutdown Earthquake, since it represents the most severe event that must be considered in* the plant design.
The scope of the review included three major areas:
the integrity of the reactor coolant pressure boundary; the integrity of fluid and electrical distribution systems related to safe shutdown; and the integrity and funtionability of mechanical and electrical equipment and engineered safety features
- systems (including containment).
A detailed review of the facilities was not conducted by the staff; rather our evaluations relied upon sampling representative structures. systems. and components.
Confirmatory analyses using a conservative seismic input were performed for the sampled structures. systems. and components.
The results of these analyses served as the principal input for our eva~uation of the seismic capacity of the facility.
REVIEW CRITERIA Since the SEP plants were not designed to current codes. standards. and NRG require-ments. it was necessary to perform "more real i sti c 11 or "best estimate" assessments of the seismic capacity of the faci 1 i ty and to consider the conservatisms associated with original analysis methods and design criteria.
A set of review criteria and guide 1 i nes was developed for the SEP p 1 ants. These review cri tera and guide 1 i nes are described in the following documents:
\\
I,. 1.
NUREG/Ck-0038, "Development of Criteria for Seismic Review of Selected Nuclear Power Plants.
11 by N. M.
~Jewmark and W. J. Hall.
May 1978.
- 2.
11SEP Guidelines for Soil-Structure Interaction Review.
11 by SEP Senior Seismic Review Team. December B. 1980.
For the cases that are not covered by the criteria stated above. the follow-ing SRPs and Regulatory Guides were used for the review:
- 1. *standard Review Plan. Sections 2.5. 3.7. 3.8. 3.9 and 3.10
- 2.
Regulatory Guides 1.26. 1.29. 1.60, 1.61, 1.92, 1.100 and 1.122.
RELATED TOPICS AND INTERFACES The related SEP topics to the review of Seismic design considerations and component integrity are II-4, II-4.A, II-4.B, II-4.C. These topics relate to specification of seismic hazard at the site. i.e. site specific ground response spectrum for the Palisades site. The seismic input selected for the confirmatory analysis of Palisades facility. namely the Regulatory Guide 1.60 spectrum scaled to 0.2g peak ground acceleration. envelopes the Palisades site specific ground response spectrum as shown in Fig. 1. there-fore the results for these four safety topic evaluation will not affect the review of seismic design considerations and component integrity.
I ]
' EVALUATION A.
GENERAL APPROACH The seismic reevaluation of Palisades Nuclear Power Plant was initiated by conducting a detailed review of the plant seismic documentation.
The results of this review are summarized in the draft reports "Seismic Review of Palisades Nuclear Power Plant - Phase I Report.
11 Thens the staff and our consultants conducted a site-visit. The purpose of this site-visit wete:(l) to observe the as~built plant specific feature re-lative to the seismic design of the facility, (2) to obtain seismic design information which was not available to the staff in the dockets (3) to dis-cuss, with the licensee, seismic design information that the staff and our consultants had reviewed, and (4) based on the results of this field inspec-tions experience and judgements to identify sample structures, sYstemss and components for which the confirmatory analyses (or audit analyses) would be performed.
The results of these analyses, then, served as the basis for safety assessment of the plant facility.
When a structure was evaluateds it was judged adequately.designed if the resu1ts from the structural analysis met one of the following three criteria:
- 1. The loads generated from confirmatory analysis were less than original 1 oads;
- 2.
The seismic stresses from confirmatory analysis were low compared to the yield stress of steel or the compressive strength of concrete; and
- 3.
The seismic stresses from confirmatory analysis exceeded the steel yield stress or the concrete compressive strengths but estimated reserved cap~
acity (or ductility) of the structure was such that inelastic deformation without failure would be expected.
- B.
- If the above criteria were not satisfied. a more comprehensive reanalysis was required to demonstrate its design adequacy.
For piping reevaluation. the results from the audit analysis of each of the sampled piping systems were compared with ASME Code requirements for class 2 piping systems at appropriate service conditions. This comparison provided the basis for reevaluating the structural adequacy of piping systems.
Because limited documentation exists regarding the original specifications applicable to procurement of equipment. as well as for the qualification of the equipment. the seismic review of equipment was based on expert experience and judgement.
Two levels of qualification were performed, structural integrity and *functionabdity. The results of this reevaluation of equipment served as the basis for modifications or reanalysis to be undertaken by the li.censee
- CONFIRMATORY ANALYSIS In order to provide independent analytical results for the reevaluation. a relatively complete seismic confirmatory analysis. which started with a.
- definition of seismic input ground motion and end~d with responses of the
. safety related structures and selected systems and components. during the postulated earthquake event. was performed.
The analysis procedures and results* are briefly discussed on the following sections.
- 1.
SEISMIC INPUT When seismic review 0f Palisades plant started in mid 1979. the site specific ground response spectra were not available.
In order to per-form the review on a sampling basis that could be applied with confidence.
a more conservative ground motion. namely Regulatory Guide 1.60 horizontal gr~und response spectrum (R. G. l.60 spectra) scaled to 0.2g. the original
- design peak ground acceleration {PGA), was used as the horizontal com-ponent of postulated ground motion for analysi.s.
The input motion in the vertical direction was taken as 2/3 of the value in horizontal direction across the entire frequency*range.
Recently, the site specific spectra development program was completed and the spectrum generated for the Palisades site is available for any future work that may be required.
As discussed in NRC NUREG/CR-1582
\\t repo'rt, "Seismic Hazard Analysis," (ref. 2) and NRC letter to all SEP licensees (except San Onofre 1) dated June 17, 1981 (ref. 3), the local soil column effects for Palisades, Lacross and Yankee Rowe were not considered during the development of SEP site specific spectra. Following development of the original site specific spectra. an additional investi-gation of the local soil amplification was performed by the staff and its consultant resulting in a ground response spectrum specifically for the
\\
Palisades site (Attachment 1 ). This site specific spectrum is appropriate for 3ssessing the actual safety margins present for any structures, systems, and com-ponents that have been identified as open items.
In Figure 1, a comparison is made for the ground response spectra that were used for the original plant design and for SEP seismic reevaluation (Reg. Guide 1.60 spectrum and the site specific spectra).
- 2.. ACCEPTANCE CRITERIA AND SCOPE The specific SEP reevaluation criteria are documented in NUREG/CR-0098 and SEP Guidelines for Soil-Structures Interaction Review.
These documents provide guidance for:
a) selection of the earthquake hazard; b) design seismic loadings; c) soil-structure interaction; d) damping and energy absorption; e) methods of dynamic analysis; f) review analysis and design procedures; and g) special topics such as under ground piping. tanks and vaults. equipment qualification. etc.
These criteria are felt to more accurately represent the actual stress level in structures. systems and components during a postulated earthquake event and consider. to certain extent. nonlinear behavior of the systems.
The SEP seismic reevaluation of Palisades facility was a limited review centering on:
o Assessment o~ the general integri~ of the reactor coolant pressure boundary.
o Evaluation of the capability of essential structures. systems. and com-ponents required to shutdown the reactor safely and to maintain it in a safe shutdown condition (including the capability for removal of residual heat) during and after a postulated seismic event.
A total of two (2) structures. five (5) piping systems. twenty-one (21) equipment components (mechanical and electrical) were fully evaluated and several others samples were evaluated on a limited basis in this work.
They are:
I
- o Structures - containment and aux1liary buildings.
o Piping systems - auxiliary feedwater. main steam. RHR. component cooling. and regenerative heat exchange letdown lines.
o Equipment*- 15 mechanical equipment and 6 electrical equipment.
o Others - Field erected tanks and buried pipings.
Additional samples will be selected.if any open items cannot be resolved by analysis.
- 3.
ANALYSES OF STRUCTURES Analytical procedures and methods conforming with the current state of the art were used.
These procedures considered the three-dimensional dynamic response of buildings. soil-structure interaction effects. a wide range of dynamic properties for the soil foundation~ structural damping in accordance with calculated stress levels. equipment masses. and so forth.
A.
ANALYSIS OF CONTAINMENT BUILDING The containment buildin~ (containment shell. internal structures. and foundation mat) was modelled as two canti 1 ever 1 umped mass-spring systems coupled at the found~tion mat.
Because of the high degree of symmetry of this building~ a axisymmetric model was considered adequate to present the structure. Since soil spring constants were calculated to account for the soil-structure effects. the structural foundation was considered as an embedded ri.gid disk on a layered elastic half space.
The detailed discussion of modelling techniques and the final dynamic model used for the analysis is found in NUREG/CR-1833.
The input ground motion.
R. G. 1.60 spectrum scal~d to 0.2g. was defined at the free field ground surface.
As required by SEP soil-structure *interaction guidelines. this
- input ground motion was applied direttly ~t foundation of structures without considering-any reduction from the foundation embedment.
The response spectrum analysis approach conformed with the SRP requirement in that a*
combination of moqal and directional responses~ etc.~ was used to generate the structural responses.
The final analytical results used for the evalua-tion of the structure were envelopes of the three sets responses generated by considering three levels of soil shear moduli for the purpose of account-ing uncertainty of soil properties. These three soil shear moduli are:
(a) the best estimate of soil shear modulus of the foundation~ (b) 50 percent of the shear modulus corresponding to the best estimate of the large strain condition~ and (c) 90 percent of the modulus corresponding to the best. estimate of the low strain condition of soil. The final results (dynamic moments~
shears and axial forces) which were used for the reevaluation of containment~
structure are summarized in Chapter 5 of Palisades NUREG report (r~f. 1).
The time-history analysis approach together with an artificial time history record (acceleration) was used for generating in-structu~e (or flbor) re-sponse spectr~.
Again~ smoothed envelopes of the three sets of in-structure response spectra corresponding to three soil conditions were used as input motions for the evaluation of piping systems and equipment.
Appendix B to the Pali sades NUR.EG report contains a summary of al 1 the generated i n~structure.
response spectra. The results of evaluation showed that containment building is capable to withstand the postulated seismic event
- B.
AN~LYSIS OF AUXILIARY BUILDING The same acceptance criteria and analytical approach used for con-.
tainment building were applied to the auxiliary building except a fully three-dimensional lumped mass-spring dynamic model was developed to account the asy~metric effects of this building.
The details of
.modelling techniques~ analysis procedures and analysis results (dynamic forces used for structural evaluation and in-structure response spectra used for equipment and piping evaluation) are found in Chapter 5 and Appendix B of the Palisades NUREG report.
The results of evaluation showed that the auxiliary building is capable to withstand the postulated seismic event.
- 4.
ANALYSIS OF FIELD TANKS AND BURIED PIPING Based on the criteria discussed in NUREG/CR-0098~ an equivalent static analyses with 0.2g R. G. l.60 spectrum as input motion was performed for the field erected tanks and underground piping.
The detailed evaluations including water sloshing effect to the tanks and the effects of relative motion between buildings to buried pipings etc.s were described in the Palisades NUREG report.
The results of this evaluation demonstrated that tanks and underground piping were adequately designed.
- 5.
ANALYSIS OF PIPING SYSTEMS As discussed in the section B.2~five piping lines* were *selected and analyzed to verify the adequacy of the original design and confirm the originai analyses results. The piping selected were portions of the auxiliary
.1
- feedwater, the steam. residual heat removal (RHR), component cooling, and regenerative heat exchanger (RHE) letdown systems. The selections were based on:
(1) the expert's judgment and observations during the walkdown of the facility, (2) review of the original analyses and de-sign, and (3) a desire to provide a range of piping sizes. Audit analyses which incorporated current ASME Code and Regulatory Guide Criteria and used the floor response spectra as input motion were per-formed for each portion of piping system selected. The results from these analyses were compared to ASME Code requirements for Class 2 piping systems at the appropriate service conditions. This comparison provided the bases for assessing the structural adequacy of the I
piping under the postulated seismic loading condition. Assumptions made for the analysis, methodology employed and detailed preliminary results are found in the INEL report (Reference 4).
The preliminary_ results of confirmatory analysis showed that some loca-tions of piping systems were found to be overstressed and some relatively large deflections were identified under the postulated seismic loading.
After the incorporation of additional information which reflected the modifications made in response to IE Bulletin 79-14 (ref. 5),a new audit analysis was performed for each of these sampled piping systems and found that piping systems are capable to withstand the postulated seismic input.
- 6.
13 -
ANALYSES OF SELECTED MECHANICAL AND ELECTRICAL EQUIPMENT The evaluation of equipment was done on sampling basis. Safety related components required for safe shutdowns the primary pressure boundary s and engineering safeguard features were categorized as active or passive and as rigid or flexible according to the criteria in R. G. 1.45 and SRP 3.9.3. A representative sample (or samples) from each group was selected and evaluated to determine the seismic design margin or adequacy of each group.
In this ways groups of similar components were evaluated without the need for detailed reevaluations of all individual components.
The licensee was asked to provide seismic qualifications data for each sampled component including design drawings~ specificationss and design calculations. After a detailed evaluation of each component was completeds conclusions were drawn as to the overall seismic capacity of the safety related equipment at the Palisades facility *. The description of selected componentss analytical procedures and evaluations are found in Chapter 6 of the Palisades N.UREG report.
As discussed in the NUREG reports a total of 15 open items (structural and/
or functioinal integrity) out of 21 sampled equipment were addressed as a result of evaluation.
Some of t~ese items remain open due to lack of design information. After the review and incorporation of* additional information submitted by the licensee (refs. 6-10), the results are summarized b-eiow:
o 9 mechanical equipment items and one electrical equipment item were found to be adequately designed.
- o 5 mechanical equipment items were left 6pen (structural and/or functional integrity) due to lack of design information. The licensee agreed to provide additional calculations for _demon-__..
strating the design adequacy of these items by December 22, 1981.
o The di es el generator oil storage tank supports and control r*oom electrical panel anchorages were found t~ require upgrading.
These*
modifications will be completed by the end of the current refueling outage.
o The anchorage and support systems for safety related electrical equipment were found adequately designed.
However~ the structural adequacy of the load path between electrical internal compone"ts or devices through the panel frame and bracing to the anchorage and support system was not evaluated. The l_ice_nsee _aqreed to_submit their response regarding this matter by December 22, 1 981.
o The functionality of all safety related electrical equipment.as well as the structural integrity of internal components of all safety related electrical equipment is being evaluated through SEP Owner Group program. This program is scheduled for the completion by the end of 1982.
o Qualification of electrical cable trays is being evaluated by testing*
through SEP Owners Group program. This program is scheduled for com-pletion by June of 1982.
CONCLUSION Based on the review of the original design analyses, the results of confirmatory analyses performed by the staff and its consultants~ and the licensee's responses to the SEP seismic related safety issues~ the following conclusins can be drawn:.
Structure - All safety related structures and structural elements of the Palisades facility are adequately designed toresistthe postulated seismic event (ref. 1 )
- Piping Systems - According to the ~relimir,~-> ~esults of $EP piping audit analyses to be overs tre:::.::. o.-< :
- tified under t~:.... ;...
pletion of a ~-
s.c::;9led piping systems were found
~~ y large deflections were ideri-
- *;oading.
As a result of com-
- safety related piping systems in the size of 2 1/2 11 and larger, these pipirg systems have been found to be capable of withstanding the postulated seismic event (Attachment 2).
Mechanical Equipment - A total bf 14 mechanical equipment items were sampled.
From the 14 items. 9 have been determined to be adequate.
The remaining open items are due to lack of design information.
This does not necessarily imply that safety deficiencies exist. Rather. it is the staff's judgement that documentation of the adequacy of these open items can be accomplished by January 1. 1982 and will be addressed in a supplement to this evaluation (Attachment 3).
Electrical Equipment - As a result of SEP seismic review. three (3) activities have been or are being completed by the licensee:
a) upgrading of anchorage and support of all safety related electrical equipment required by NRC letters dated January 1. and July 28 of 1980 (ref. 11 & 12) has been completed, and found to be adequately desi~ned (Attachm~~t 3), (b).a program has been initiated for the documentation of seismic qualification (functionality of the equiment and structural integrity of internal components) of all safety related electrical equip-ment. namely the SEP Owners Group program. and (c) a program for seismic qualification of electrical cable trays based upon testing by the SEP Owners has been implemented.
These latter two programs are intended to confirm the adequacy of existing designs and equipment.
- Recently, NRC has initiated a generic program to develo~ criteria for the seismic qualifications of equipment in operating plants; Unresolved Safety Issue (USI) A-46.
This program is scheduled for completion in March 1983.
Under this program, an explicit set of guidelines (or criteria) that could be used to judge the adequacy of the seismic qualifications (both functional capability and structural integrity) of safety related mechanical and elec-trical equipment at all operating plants will be developed.
Considering that:
(1)
All safety related electrical equipment has been properly anchored; (2)
Past experience and testing results (from both nuclear and nonnuclear facilities) indicate in general that electrica1 equipment will continue to operate under dynamic loading conditions with only limited transient behavior, if the equipment is adequately anchored; and (3) the SEP Owners Group programs from which a set of general analytical methodologies is being developed for the seismic qualifications of cable*
trays and for documentation of other safety related electrical equipment (functionability);
it is our judgement that for the interim period until a technical resolution of USI A-46 is reached regarding methods for assessing seismic qualification of equipment in operating plants, the safety related electrical equipment at Palisades plant will function during and after an earthquake up to and in-cluding the postulated SSE.
If additional requirements are imposed, as a result of USI A-46, regarding functional capability of safety related electrical equipment, the Palisades facility will be required to address these new re-quirements along with other operating reactors.
- Furthermore, since the ground response spectrum (0.2g R. G. 1.60 spectrum) used for Palisades seismic reevaluation envelopes the Palisades site specific ground response spectrum, additional safety margins in the structures, systems, and components do exist for resisting SSE seismic loadings. Thus, the staff concludes that Palisades plant has an adequate seismic capacity to resist a postulated SSE, and therefore, there is reasonable assurance that the operation of the facility will not be inimical to health and safety of the public.
i I /
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REFERENCES
- 1.
NUREG/CR-1833 Report, "Seismic Review of the Palisades Nuclear Power Plant Unit 1 as Part of the Systematic Evaluation Program, 11 December 1980..
- 2.
NUREG/CR-1582 Report,11 Seismic Hazard Analysis," Vol. 4, October 1981.
- 3.
NRC Letter, 11Site Specific Ground Response Spectra for SEP Plants located in the Eastern United States, 11 June 17, 1981.
- 4.
EGG-EA-5317 Report, "Summary of the Palisades Unit l Piping Calculation Performed for the Systematic Evaluation Program;" 1980.
- 5.
Handouts in April 4, 1981 Meeting - piping modification drawings, etc.
- 6.
Letter from NRC to CPCo dated January 1 9, 1981.
- 7.
Letter from CPCo to NRC dated March 27, 1981.
- 8.
Letter from CPCo to NRC dated July 22, 1981.
- 9.
Letter from CPCo to NRC dated August 3, 1981..
l 0.
Summary of 11/6/81 meeting held at Jackson, Michigan (dated December 11, 1981) l l. Letter from NRC to CPCo dated January 1, 1981.
- 12.
Letter from NRC to CPCo dated July 28, 1981.