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e UNITED STATES NUCLEAR REGULATORY COMMISSION W ASHINGTON, D. C. 20555 MAR.181975
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DOCITT NOS:
50-275 AND 50-323 APPLICANT: PACIFIC GAS AND ELECTRIC COMPANY (IGSE)
FACILITY: DIABID CANYON NUCLEAR IWER STATION, UNITS 1 AND 2
SUMMARY
OF ACRS SUBCOMMITTEE MEETING HELD ON FEBRUARY 18-19, 1975 An ACRS Subcormittee Meeting regarding the Diablo Canyon Nuclear Power Station was held in San Luis Obispo, california on February 18-19, 1975.
The agenda for the meeting is attached as Enclosum No.1. A complete list of attendees is given in Enclosure No. 2.
Introductory Statement by Applicant The meeting opened with an introductory statement by the applicant which imluded a status report on construction and fuel load. Construction has reached approximately 90% and 50% completion on Units 1 and 2, respectively. Fuel load for Unit 1 is scheduled to begin on October 15, 1975, and Unit 2 in late sunmer of 1976. Shipment of fuel to the site for Unit 1 is scheduled to begin in June of 1975.
Outstanding Items in Safety Review The staff then surmarized the status of the outstanding items in the Diablo Canyon safety review. These itcmc had been pmviously sumarized in Section 22 of Supplement No.1 to.the Diablo Canyon SER; this Supplement was issued on January 31, 1975. Among the nom important of these items are our evaluation of the earthquake potential of the Hosgri Fault, effects of tsunamis caused by near-shom genemtors, seismic qualification of electrical equipment, ECCS and AIWS. The status of each item was reviewed in detail, with the staff indicating where inforuntion from the applicant was outstanding and when msolution of each item was likely.
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' Statement by Sandra A. Silver At this point, a statement ms mad into the mcord by Sandra A. Silver, a msident of San Luis Obispo County and an intervenor in the Diablo Canyon proceedings. Ms. Silver commented on seveml issues involved in the Diablo Canyon safety review, and expressed strong objections to the location of the plant in San Luis Obispo County. Dr. Okmnt indicated that her comments would be pas. sed on to the Full ACRS Comittee.
Geology and Seisnology The applicant then began his presentation on Geology ard Seismology.
This presentation consisted of four sepamte talks by PGSE consultants:
(1)
Dr. Richard Jahns, principal geologist since the beginning of the project, discussed the geological background and the developnent of the geology report for the site. He emphasized p
the general mgionalization of the site arxl its location in California geology.
(2)
Mr. Douglas Hamilton, geology consultant, dealt specifically with the offshom seismic interpretation progmms.
e (3)
Dr. Stewart Smith, the seismologist of moord, discussed existing seismic data and a determination of the postulated earthquakes that should be considered in the design of the plant.
(4)
Dr. John Blume, structuml engineering consultant in the ama of earthquake engineering, discussed the methods used for development of seismic input on events into vibratory grourd notion.
Dr. Jahns concentmted on two areas in his pmsentation:
(1) a brief surmary of the early geologic investigations at the site, with emphasis on the problem of potential surface taulting; and (2) a summary of regional tectonic chamcteristics of Southern (51ifornia that are l
pertinent to appraisals of the site. The exploration of the site as far as artificial exposums were concerned was aimed at a detailed apprnimi of the sub-horizontal contact between the wave cut bedrock surface and the overlying mrine termee deposits. Since these deposits can be dated, it would then be possible to demonstmte that if faults l
were found in the bedrock, ard these faults did rot disturb the overlying dated mterial, then an age ceiling could be imposed on the latest
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MAR. I 81975 movement of these faults. As a result of the extensive trenching and excavation progmm which was conducted, it ms concluded that potential surface faulting need not be considered in the plant design. With regard to the regional situation, Jahns emphasized that the different major faults must be evaluated in the context of their own physical characteristics, continuity, segment lergth, etc., and also with regartl to their positions and behavior throughout different parts of geologic time. He indicated that the San Andreas Fault was clearly the dominant feature involved, but also discussed the importance of the Sur Nacimiento fault zone. He concluded by stating that for the faults in this mgional setting, it would seem significant in corsidering the respective roles and orxlers of significance to consider them most specifically in the context of the past five million years since that is basically what is involved in appraising their present ard potential futum activity.
Doug Hamilton began his presentation by discussing some of the work that has been done in surveying the offshore geology. He irrlimted that there am two elements of this surveying:
(1) seismic reflection profiling; and (2) gmvity survey and mapping progmm. There have been four different surveys applicable to the region offshore from the Diablo Canyon site:
(1)
USGS Bartlett cruise in 1972 urder the direction of Ely Silver; (2)
USGS Kelez survey in 1973 under the direction of Holly Wagner; (3)
PGEE sponsored work in 1973-1974 by the firm of Bolt, Beranek and Newnan of Houston; (4)
PGSE sponsored work in 1974 by the firm of Aquatronics, Inc.,
of Houston.
Hamilton tsed detailed nups and truck charts to indicate the amas of coverage by each of these surveys; he stated that the interpretation of the offshore profiling involved integmtion of data from all four of these surveys. These data were discussed in considerable detail; the discussion also included a detailed interpretation of the Hosgri Fault. He described the Hosgri Fault as continuing as either one or a group of two or thme breaks, and tmced the fault from near Pbint Sal northmrd to the vicinity of Cape San Martin whem the breaks die out. The plant site -is about two and a half miles to the inner breaks at the Hosgri Fault at its neamst point of approach. Hamilton
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then turned his attention to the compilation of the gmvity survey data.
The map gave gmvity anomaly values for the offshore area ranging fmm Point Conception up the coastline to a point around Cape San Martin.
He emphasized the importance of this map, in that it gives definite indications of major structural features that have been napped independently by other means, e.g., the Santa Lucia Bank and Hosgri Faults. Hamilton concitxled his discussion by sunmarizing the major features of the area, including the large offshore Santa Maria Basin, the lesser or folded basins, including San Luis Obispo syncline, the Pismo syncline, the area of the Santa Maria Valley and the onshore Santa Maria Basin which lies generally south of the Santa Maria Valley down to whem the transverse ranges come up south of Ianpoc.
The structumi disturbance of these includes very large faults which have very pronounced gmvity expmssion. These include the Santa hrh Bank and San Simeon Faults, the Faults of Rincor.,da and the Sur Nacimiento system, and to the south, the faults of the transverse ranges system including the Santa Ynez and a system of faults which g
has no specific name that bmnches off from the Santa Ynez and then heads up toward Point Sal. Lesser faults am also shown in this gmvity expmssion, including the Hosgri Fault which does have local gmvity expmssion, but clearly not expression which is comparable either to the Santa Lucia Bank or San Simeon Faults and to other faults mapped onshom which include the Edna, the Pismo, and related faults in the ground east of the San Luis Range area.
Seveml questions were asked regarding Hamilton's pmsentation. Dr.
Page asked tether there was firm evidence that the Hosgri and San Simeon Faults are not connected? Hamilton discussed the data in the reg; ion of the proposed connection; he felt that the evidence is good that they are not all one continuous system, although he qualified the statement by saying thdt both faults have to be considered part of the system of faults on the eastern boundary of the Santa thria Basin. Dr. Trifunac asked what Hamilton's speculations would be regarxling the geneml sense of motion, the amplitude of notion, and the effects of these notions on the najor faults that were discussed? Hamilton responded in light of the Hosgri Fault, and indicated that the Hosgri might be considemd capable of a few feet of movenent, although he did rot specify whether that movement would be vertical or lateral.
Dr. Stepp of the NRC staff then ccrnmented on the information presented.
He indicated that the staff had mviewed the material pInsented, awl that additiomi infornation on the subject had been requested from the applicant. This request included questions on the mlationship
I MAR.181975 of the Hosgri and San Simeon Faults, a note detailed documentation of the structural relatiorchip of these faults in their assumed area of approach, and a discussion of the structural relationship of the Hosgri Fault to the transverse ranges faults. 'Ihe staff also asked for a discussion of the ungnitude of earthquakes that one might expect on faults within the San Andreas Fault System that have different orders of structural significance. Finally, additional documentation was requested regarding the location of the 1927 earthquake that occurred off Point Conception. Stepp indicated that the staff hoped to complete its review of this naterial in May of this year.
F. McKeown of USGS concurred with the staff's conments, and emphasized that the relationship of the southern end of the Hosgri Fault to the tmnsverse ranges could be extmmely important in locating the 1927 event.
Dr. Okmnt then asked how nuch of the offshore infornation that is reported now was available in sufficient scope in 1967 to prompt gg someone to look for the~ structures now being reported and discussed?
Dr. Jahns indicated that the potential existence of the Hosgri Fault was suspected in 1967, but that no detailed offshore sub-bottom datt were available. 'Ihe applicant empMsized that the geological studies perfomed prior to the construction permit review were quite cxtensive, and that there wps no question in their mind that a very complete state of the art investigation of the site had been perforned.
Dr. Smith began his pmsentation by discussing the earthquakes which had been postulated as design basis events for the plant; he emphasized the levels of conservatism that had been employed at the construction permit stage, e.g., the assumption of an earthquake umssociated with a fault occurring directly beneath the plant. Smith indicated that the discovery of offshore faults in recent years was not really a surprise, and that events subsequent to the initial analysis at the CP stage have borne out the wisdom of the very conservative approach that was taken in considerir.g that earthquakes of the size postulated could occur as close to the plant site as was assumed. He further stated that, based on Hamilton's interpretation of possible notion on the Hosgri Fault, the greurd notion produced by an event of this cize, at a distance of three to five miles at closest approach would certainly fall within the envelope of the kinds of greurd notion that have been proposed for the site. With regard to earthquakes on the offsMre faults that have been analyzed, Smith indicated that these events have contained a large component of vertical slip. He then discussed specifically the 1927 earthquake that was centered
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I MAR. I 81975 off Pbint Conception; analysis of the data indicates that the aftershock region had to be substantially closer to the shom than the min shock location given by Byerly in 1930. However, Smith stated that he cannot clearly associate this event with one of the pmsently mpped faults, although it is his opinion that the most likely association is with the tmnsverse mnge structures.
After several questions fmm the ACRS consultants mgartling location and depth of the 1927 event, arxi postulated earthquakes on the Hosgri Fault, Dr. Blume began his pmsentation by reviewing the four specific fault-earthquake situations which were postulated for the design of the plant. He emphasized that, at the CP stage, very few methods wem available for converting mgnitude and distance into site accelemtion, and that site or peak accelemtion was only one considemtion that was used in the design. Other equally important considemtions were the damping factors assumed for various structums and system, the dumtion of the shaking, the pmbability of peak accelemtion, given a certain
=4 earthquake, and the pmbability of the spectml msponse diagmm, given that peak accelemtion. Blume discussed in detail the mthods that wem used for estimting site accelemtion; he irrlicated that the principal one employed was the Site Accelemtion Magnitude (SAM) or Blume Method. After a detailed discussion of the SAM method as applied to the four earthquake situations mentioned above, Blume stated that he is pleased with the fact that the m thods used nearly 8-10 years ago at the CP stage compam extm.mely well.with those in use today, e.g., those pmposed by Smuble S Seed, Cloud S Coress, and Donovan.
Blume then discussed the mcent amlysis that was performed based on components of the Parkfield-5,1966 arri Castaic,1971 earthquakes, each normlized to a peak ground acceleration of 0.5g, mther than the 0.tig that was used in the origiml design. He also mentioned the Koyna tmnsverse earthquake in India as being close to the situation at the Diablo Canyon site; an acceleration of 0.119g was observed fmm this event.
Dr. Trifunac asked a question regarxiing the SAM method as described in Dr. Blume's paper in the 1965 World Confemnce Pmceedings. Trifumc indicated that the use of this method by Blum appears to msult in accelemtions which underestimte all present available data by a factor of 0.5 to 0.8 on the logarithmic scale. After a lengthy discussion, Blurn agmed to get together with Trifume in an attempt to msolve this apparent disempancy.
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. Dr. Kapur of the NRC staff emphasized the part played by damping values in the detennimtion of response spectra. He indicated that the damping values used by the applicant were very conservative, and that the staff considers the response spectra calculated by the applicant to be quite conservative.
Dr. Okrent then asked the USGS to elabomte on their statement that a design accelemtion value of 0.5g is not adequate? James Devine of USGS indicated that this statement was meant to leave the issue open because he did not feel that all questions had been answered at this point. Devine stated that recent work by Dr. Smith concerning the location of the 1927 event, along with some unpublished work by the USGS, indicate that there is still profitable information available comerning that earthquake which could alter the obligation to put it on the Ibsgri. He also emphasized the importance of the mnking of faults with regard to the resolution of this question. Okmnt then asked what approach the USGS would take mganiing the mtum of
%,9 the Hosgri structurn if the 1927 event had never occurmd? Pmnk M:Keown of USGS responded that there is no definitive evidence to tie the Ibsgri and San Simon Faults together, but that the possibility canrot be ruled out entirely. He indicated that it is very difficult to assign a given size earthquake to the fault because you are not dealing with a single continuous break; it consiscs of mny, mny bIraks. Dr. Trifume asked whether the applicant's four pruposed design basis earthquakes could be comidered reasomble if the 1927 event were eliminated? Devine replied that he felt that all four were reasonable at the time of the CP, and that he still feels that they are masonable with a proviso on carthquake D (the event umssociated with a ' fault), that being that the Hosgri be examined more carefully after the applicant Insponds to the staff's recent request for additiomi infonrution. He irdicated that this information will help to better estimte the maximum earthquake that could occur on the Hosgri Fault which in effect row controls the undesigmted earthquake D.
Dr. Okrent asked the staff whether the acceptable seismic design criteria for Diablo Canyon 1 and 2 would be the same for additiom1 units, if such were proposed? Dr. Stepp irxiicated that the staff's seismic design criteria have constantly been upgmded as our underw standing of the problems of earthquakes and earthquake spectna properties change. He stated that we would always consider the probable mrdnum earthquake for the site in our evaluation, reganiless of whether the plant was partially built or not. Dr. Shao emphasized that the
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staif will consider all steps in going from the g value to msponse spectra and damping values, including the nethods used, and then a decision would be nude regmling the adequacy of the seismic design.
After note discussion, Shao indicated that if the g value tolds at 0.5, and the applicant has employed the criteria and methods which have been stated, then the plant is probably adequately designed for seismic loads. Dr. Okrent then asked what probability per year of safely shutting down the mactor in the event of an earthquake, that the staff is seeking for Diablo Canyon? Dr. Denton replied that the staff does not use a probability approach in selecting safe shutdown earthquakes (SSE). He stated that the Comnission's criteria, as set forth in Appendix A to Part 100, provide a fnunework to work in to arrive at an SSE; we then have to couple that with the design approach and the design of structures and components in ortier to arrive at an evaluation of adequacy of the seismic design.
Dr. 'Ihompson pointed out that, after all the discussion that had priry.
transpimd, the question of whether the Hosgri Tault would be epted to exhibit predomimnt strike or dip slip had not really been answerix1. Holly Wagner of USGS connented in detail on the findings of his survey, but did not reach any firin conclusions rugmiing the preference for strike or dip slip.
Seismic Design a
Mr. Wollak of mf,E began the session on seismic design with a pmsentation on the design criteria for the najor components, and how Dr. Blunn's criteria have been implemented. Wollak stated tlut the seismic amlysis of Seismic Category I structures, systems, anci components is based on the input fme field ground notions and the resulting response spectra for the operating basis and safe shutdown earthqtukes. Four dynamic methods of seismic amlysis were used:
(1)
Time history modal superposition; (2)
Response spectrum nodal superposition; (3)
Response spectrum single degree of freedom; and (4)
Method for rigid equipnent and piping.
Af ter discussing design procedures in detail, Wollak conmented on some recent work which was done to comp 1re the safe shutdown earthquake response of typical Category I structures, systems, and components to that which would be induced using nodified input response spectra and
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the damping values given in Regulatory Guide 1.61.
These modified input response spectra were derived from acceleration time histories for cmponents of the Parkfield-5,1966 and Castaic,1971 earthquakes, each normlized to 0.5g.
The spectral content of these recortis is considered mpmsentative of the vibratory ground motion expected at a site with foundation material similar to Diablo Canyon, and generated frua a nearby source. A comparison of these nodified spectra with the spectra and damping used in the SSE design confirms the seismic design adequacy of typical Category I structures, systems, and cmponents.
Wollak concluded his presentation by stating that the seismic design basis for mjor plant structums and cmponents includes significant conservatism in the fom of design spectra (unusually rich in high frequencies), very low assumed damping values, and an acceptance criteria based on overall elastic behavior under seismic loadings.
Dr. Okrent asked whether a calculation had been done using 0.5g peak acceleration arxi the response spectra and damping values of Regulatory pg Guide 1.60? Wollak replied that they had not done this. The staff then cmmented on the applicability of the response spectm in 1.60, and also on the reasoning behind the selection of the Parkfield and Castaic earthquakes as comparisons for the Diablo Canyon site.
Dr. Okrrnt emphasized the importance of knowing, with some degme of assumnce, that all safety related structures, systems, and cm will be able to survive an earthquake of given acceleration, e.ponents g.,
0.5g.
Mr. Lindblad stated that once scismic design criteria were chosen for the plant, all structures, systems and components were designed to meet these criteria. He indicated that he feels that there is conservatism in the ovemil design.
After additional discussion en loading factors and the different seismic design situations where the OBE and SSE control the design, Dr. T. C. Esselnnn of Westinghouse presented the seismic design criteria that wem uned for the prim 1ry loop components and piping.
He mviewed the metinis used for each cmponent and for piping, and indicated the margins that resulted frun the analysis. Dr.
Okrent asked whether the staff reviewed the seisnic modeling of various components in the primuy loop. Dr. Kapur replied that Westinghouse has documented nnny codes involving this nodeling, and that the staff has reviewed these codes in some detail. The possibility of failure of the turbine building (a non-seismic Category I strmture), and the effect of such a failum on Category
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, I systens was discussed. The staff stated that all such systems in the turbine building had been adequately protected against such a failure.
With agard to this iten, Dr. Bush asked about the supports on the valves, that in the event of loss of power during an earthquake, what is the reliability regarding closure of the valves? Westinghouse agreed to provide information in response to this question at scme later date.
ACRS Questions Regarding Geology-Seismology and Seismic Design Following a short executive session, the meeting reconvened, and the following questions were raised by several of the ACRS members and consultants:
Dr. Trifunac (1) In light of previous discussions with John Blune, justify the apparent discrepancies in the relationships used.
MNph (2) Referencing question 1, what would be the calculated peak acceleration using other currently available methods?
(3) What would be the effect on the response of the plant of a small magnitude earthquake which produces very high peak accelerations?
(4) When this peak acceleration has been deriv ~
would it be possible to calculate confidence levels on this val (5) What is the mavi== historic, as well as predicted, modified Hercali intensity at the site due to any earthquake any place, and what would be the peak accelemtion resulting frun it?
Dr. 'Ihompson (1) He inquired about copies of USGS Open File Report 74-272. Mr.
Devine of USGS agreed to provide seveml copies of this report.
Dr. White (1) Provide additlomi evidence to demonstrute that the Castaic and Parkfield earthquakes (normalized to 0.5g) really have lesser effects on the Diablo Canyon structures than the origim1 design earthquake.
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MAR.I 8 1975 Dr. Okmnt (1) What kirxi of errors can arise in the seismic design analysis?
(2) What are the sourres of error in going frun the earthquake itself via a one-dimensional seismic model to the finite element model?
(3) Assuming that some peak g value is adopted by the staff as adequate, justify that the calculations based on the Castaic and Parkfield spectra provide the necessary assurance.
(4) How does the staff decide what constitutes an adequate audit of the seismic design analysis? (Refemnce the Appendix to Draft WASH-1400 which includes a partial design check).
Dr. Okrent asked the applicant and staff to be prepamd to discuss these questions at the next Diablo Canyon Subcormtittee Meeting.
(The last gg question is for the staff only).
Seismic Design (continued)
Mr. Dorrycott of Westinghouse then presented the design criteria, and qualification mquirements for safety related instrumentation. He listed the instrument control electrical equipnent that had been qualified in testing progmms; this equipment was tested in full-scale testing programs and qualified to design acceleration levels. Dr. Okrrnt asked if an earthquake with a larger higher frequency canponent tlun the one analyzed would appreciably affect the perform 1nce of the instrunentation?
After some discussion regan11ng the effects of damping, etc., Okrent asked the applicant and Westinghouse to look into this natter. Dr. Kapur cccmented that equipnent at higher elevations in the plant does not experience the very high frequency component, and so the prublem is not so severt. Mr. Eberr. ole pursued the discussion with regani to possible contact chatter in switches, etc. Dorrycott reuponded that Westinghouse in pursuing a failurt mode and effects analysis with rrgani to the resolution of this probicm. The staff indicated that they hoped to have the issue of scisntic qualification resolved prior to completion of the Diablo Canyon review by ACRS. With regani to qualification, Dr. Bush brought up the possible interactive effects of seismic and envirurrnental qtulification; he asked if any work had been done in this arra? After some discussion, it was agreed that this problem tud not trally been ackhrased.
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1 MAR. I S 1975 Dr. Bush then brought up the subject of experimental confirmation of vibration chamcteristics of major reactor ocmiponents, and the response of safety instrumentation to seismic loadings. 'Ihis was an agenda item for this meeting as well as having been cited in the ACRS CP letters for both Unita 1 and 2.
Mr. Lindblad indicated that a number of progmms have been instituted in response to this concem:
(1) Equipment qualification dynamic tests, as discussed by Mr.
Dorrycott.
(2) Dynamic tests of expansion anchors (tests spewnwd by PGSE at the University of California).
(3) Component tests conducted at Indian Point 2 and San Onofre on ccmiponents similar to those which will be used at Diablo Canyon.
With regard to item 3, Dr. Lin of Westinghouse discussed the applicability of these conponent tests to Diablo Canyon. He first discussed in detail the seismic qualification of instrvmentation, in response to earlier questions. He then indicated that vibration testing of the reactor coolant loop and steam generator had been perforined at Indian Pbint 2.
He indicated that data were availmhie from San Onofre, both frun shake tests and fran effects of the San Fernando earthquake. Lin also discussed some fulle,cale testing on a Westinghouse reactor in Japan.
(84) Testing of models of pipe and pressure vessels for seismic damping chamcteristics (tests sponsored by PGSE at UCLA).
(5) Installation of plant seismic instrunentation to twoord the small earthquakes that may occur during the coming years of opemtion.
Dr. Okrent asked whether IC6E had any plans for full-scale shaking of the Diablo Canyon Plant? Mr. Lindblad twplied that they did not, and that they felt that the conservative damping assumed in the design provided sufficient margin such that full-scale shaking to reproduce the natural period of vibm tion was not zwally necessary. 'Ihe staff added that unless one could simulate accelerations close to the SSE, e.g., 0.14 to 0.5g, the benefits of such testing would be amall. The point was also made that artificial testing to cuch lary,e accelemtions would be extnmely difficult.
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' Seismic Semm The last agenda item of the day involved a discussion of seismic scram.
Mr. Lindblad indicated that PGEE had mviewed the mcent Liverinore mport on this subject; he stated that the mport leaves many questions open, and that at the pmsent time, PGEE believes that an automatic trip of the mactor at the onset of an earthquake does not necessarily impmve the safety situation. Dr. Okmnt asked whether the applicant had prepamd some kind of list detailing the good and bad featums of a seismic scram?
Mr. Lindblad stated that they had done this at various times, and that on the bad side, such a scram introduces a non-standard condition for the mactor, a tmnsient involved in shutdown, loss of one of the sources of power, and an additional need to monitor a changing operation in the plant on top of the stmss of the earthquake itself. Dr. Ok mnt then asked whether PGSE had evalmted the plant to see what level earthquake would lead to trip, whether you wanted it or not? Lindblad said they had not, but that he would estinate something of the order of a 0.lg acceleration value. 'lhis could be a reactor trip, turbine trip, or
- W perhaps some other ccnnponent, and would not necessarily initiate an automatic reactor shutdown. He added that he did not feel that it was good pmetice to shut the plant down for any earttquake, only for those which am potentially C=ghg to the plant; he did ret think that PGSE should tolerate spurious trips of the reactor for smC1 earthquakes.
Okmnt asked about the possible merits of an early wan for an earthquake which is going to cause a loss of coolant accident (LOCA). Dr. Kapur stated that the nest important reason for having a seismic scram is that if the earthquake is accompanied by a LOCA, the peak clad tenperatum could be significantly reduced. He then considered various postulated earthquakes, for earthquakes of the order of the OBE, e.g., slightly greater than or equal to the OBE, the opemtor is required te shut down the plant. For earthquakes nuch gmater than the OBE, some damage will be incurmd, but within the SSE, the plant is still designed to be safely shut down.
For earthquakes in this range, them are other nonitoring systems which will trip the plant. Kipur also cited the problens of spurious signals and unwanted tmnsients in concluding tMt he did not feel that a seismic semm was desimble at this time.
Mr. Ebersole mised the question of d-c power supplies with mgard to bmaker closum or trip in the event of an earthquake wherv one Ma genemtor trip. 'Ihen, what are the seismic qualifications of the switchgear and power supplies? Mr. Hermm of PGSE indicated tMt the batteries for the switchyards have carthquake bracing and are designed to withstand accelemtions of at least 0.2g.
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. l Dr. Okrent asked whether one can engineer a seismic scam systen with a high degree of reliability, e.g., a reliability such that one has a probability of spurious scram no larger than one in a 100 or one in a 1000 per year?
Considerable discussion ensued on this iten, with the geneml conclusion being reached that such zwmhility could probably be achieved if the threshold level were set far enough above the accelemtion for the OBE.
After additional discussion of this item, the meeting adjoumed for the day.
Systems Interactions
%e meeting for the second day began with the subject of systems inter-l actions. De refemnce for this discussion was an ACRS letter from Dr.
Strutton to Mr. Huntzing (dated November 8,1974) titled, " Systems Analysis of Engineered Safety Systems". In this letter, the Comittee i
indicated that attention to the evaluation of safety systems and associated W*Mab5 equipment fran a multi disciplinary point of view to identify potentially undesirable interactions between systems is hae=_ Lng increasingly desirable and important. He letter then contains several examples to illustrate this theme.
After scme general conments by Mr. Lindblad mgarding the nature of the letter and its applicability to Diablo Canyon, Mr. Ebersole posed a series of questions and situations regartling the applicability of this letter to the Diablo Canyon Plant. Ebersole had visited the plant the previous day. These questions and situations are stamarized below:
(1) In the event of fire in the turbine building, it appears that them could be ventilation problems in the 4 kV vital switchgear rooms and also in the diesel genemtor ccmpartments.
For the switchgear l
reans, there is comon atmospheric coupling between these roams, and it appears then that them would be conmunication between these l
rooms in the event of a fire in one of them. In the case of the diesel gencrutor compartments, if the generator end of the diesel is isolated, i.e., the roll down dcors are closed, one would Mve a situation where the generator could recieve very little cooling, causing a temperuture rise in that part of the room and a possible overload condition and resultant a-c power outage.
(2) %e plant Ms many' pairs of rotating shafts of various sorts serving different functions. These are typical redundant configumtions of services which are on line at all times (not engineering safety feature designs). Now, suppose one postulates the failure of one l
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i MAR. I 819?5 of a pair (say train A) which serves some specific function. His the applicant examined the consequences if the altemate service, say train B, does not respond properly as a function of time?
Examples might be service functions which control ventilating systems, m ter supplies, etc.
In other words, the interest here is the thesis of non-response of backup tmins of active services, and a consideration of the time delay involved that might be an al: normal delay mther than normal. An extension of this might be, if the backup service does not respond, what time is available to repair the scrvice or else pursue an alternate course of action?
(3) The Rasnussen Report discussed the total loss of all a-c power, and included some probabilities on the length of time beform power might be restored. With regard to this situation, has the applicant considered this loss of power in light of the stoppage of rotating shafts and a possible temperature excursion in the containment to values of the order of 4M-500*F? Mr. Lindblad indicated that they had reviewed this geneml type of situation, and that the contairment would not exceed its design temperatum. He further added that with loss of a-c power, the containment heat input is reduced by about 85% because of the loss of the rormal heat loads frun the reactor and the reactor coolant pumps.
(4) In the case of smil IDCA conditions (larger than the charging pump capacity), one has depressurization of the primry system.
For this situation, can the applicant describe the heat transport paths to the ultinute heat sink? Possible paths am the residual heat runoval system (but there is probably not sufficient flow heru), the ecmponent cooling water system (which passes through the containment fan coolers) coupled with the auxiliary saltmter system, or natural convection in the steam genemtors. As a function of brmak size, what fractions of the heat are carried along these various tmnsport paths to the ultimte heat sink?
An additional question mined was, what will be the ambient tempemturu surrounding the auxiliary feedwater pumps, as a function of time, in the absence of cooling and ventilation in these pump rooms?
(5) For the auxi.liary saltwater system, one of the auxiliaries is a ccmnon pair of sump pumps in the intake structurm to pump out Icakage, if necessary. 'Ihese pumps would be culmerged under a high wave condition. What are the criteria for the design of these sump pumps? In addition, the piping for the saltmter pumps is supported by connection to a non-seismic structure,
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MAR.181975
. namely the condenser discharge conduits. 'Ihe idea of a seismic piping system anchored to a non-seismic stmetum appears to deserve some clarification. The coupling of the auxiliary saltm ter piping to the earthen fill and the building foundation ms also discussed.
(6) Again with Irspect to the sump pumps for the auxiliary saltmter system, it was mentioned that these pumps would be flooded under very high waves. Under this condition, would the integrated intake of water into the louvres be such that the sump pumps would not be mquired in the short-tem following this flooding?
(7) The cable link that supplies power to these sump pumps is an example of cabling which is intermittently subjected to fresh-end salt-water flooding. What qualification of this cable has been performed to ensure its function under the conditions of alternate drying and subnergence in either fresh-or salt-water?
%i%
(8) With regard to the hot shutdown panel, is there a possibility that in providing this auxiliary function, you mally have not recreated a new scene for corrmon vulnerability of damage? In other words, is there really independence from the control recm with regard to this panel being a center of active functions?
Each of the items raised by Mr. Ebersole was disassed in considerable detail. Dr. Okrrnt asked both the applicant and staff to be prepared to discuss and resolve any outstanding questions on these items at the next Subccrrmittee Meeting.
Dr. Bush then raised the following tuo questions:
(1) lias the applicant considered the problen of phosphate build-up with regard to closure of valves on the turbines? This question is related to the twsponse of non-seismic valves under severe seismic shaking. Are there any reliability statistics rrgarding closure of such valves under seismic loadings (when generator load has been dropped)? Mr. Lindblad indicated that the Lirthquake Engineering Researth Institute does collect informtion of this sort. With regard to contacting the above-mentioned Dirthquake Institute, Dunh suggested that data from Alaska also be obtained, e.g., data from the 1964 Alaskan earthquake.
)
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MAR. I 81975 (2) If you assume a failure of one of the inlet lines to the steam genemtor so that you have the full impact of the jet fortes, as well as the jet forces fmm the exhaust frun the steam genemtor, and then impose a seismic loading as well, does this situation fall within the design envelope?
(3) Dr. Okrent asked that the staff reexamine in detail the modeling of the primry coolant pump under a seismic loading, to be assured that this modeling has been done properly.
(4) Mr. Koffen asked what accelerations might be experienced in the control reczn for the design SSE acceleration of 0.4g?
Mr. Lindblad estimated between 1.6 and 2.0g, but indicated that they would look further into this itm. Koffe n stated that this could be an additional argument for having a seismic scram.
As a concluding remrk to the geneml subject of Systems Intemctions, ip;hw T. Hirons indicated that the staff has had scrne preliminary discussions with ACRS as to how same of these situations sMuld be handled. It is planned that mny of them can be incorpomted into various sections of the Standard Review Plan. A special ACRS Subconmittee, with Dr.
Bush as chairman, has been set up to begin reviewing some of these items with the staff.
Electric Ibwer Systcrns Mr. lierrem of PGSE opened this subject with a pmsentation on the offsite power system for Diablo Canyon. lie stated that the inter-connected PGSE 230 and 500 kV electric transmission systems will serve as a two-system source of offsite power for the Diablo Canyon Units. The two genemting units will be connected to the transmissien system by means of tw 230 kV and three 500 kV lines emanating fmn their respective switchyards. These yards are physically sepamted and independent of each other. Each of the 230 and 500 kV lines supplying the Diablo Canyon switchyards have primary and backup protective zulaying systems and autcmitic closing features. This will ensure fast and proper clearing of all electrical faults, and will permit autcmtic restoration of power fran the systcrn if all conditions are proper. Stability studies which have been conducted on the system indicate that the loss of any single genemtor in the systcsn, including that for either Diablo Canyon Unit, while operating at full load, will not adversely affect the stability of the rrminder of the tmnsnission grid. Ile concluded by stating that the design of the offsite power system meets the intent of General Design Criteria 17 and 18. TEEE Standard 308-1971, and Regulatory
~
Guide 1.32.
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MAR. I 6 1975 Seveml questions wem raised mganiing the pasentation on offsite power. Dr. Okrent asked if figures wem available on systen reliability that would provide a basis for judging the prnbability per year of losing all offsite power to the Diablo Canyon site? Mr. I'm m e indicated that specific figures wem not available. Mr. Ebersole asked if PGSE was taking any steps to upgmde the load rejection logic to pmvent cascade as the nuclear units come on to the system? Mr. Herm ra indicated that they were. Dr. Bush asked if, under a seismic loading, can you bootstmp yourself to the turbine fmn a startup condition, as contmsted to a load rejection continuing operation? Mr. Lindblad responded tMt they could.
Mr. Nielsen of PGSE then mde a pmsentation on the onsite power system for Diablo Canyon. This system consists of the output frun the main generator and an auxiliary power system composed of 12,000, 4160, and other low voltage systems. All auxiliary system buses can be fed frun either the rain genemting unit or fmm the standby-startup
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offsite sourre. The emergency power system can also be supplied by the diesel generators. The engineered safety features arxi other energency
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services are fed frun three 4160 volt buses, each supplied by a diesel genemtor as well as by the nonnal offsite and main unit sourees. EST l
loads have been grouped to meet single failure criteria. Two diesel genemtors are sufficient to carry the emergency loads tMt are j
requimd for safe opemtion under nonnal and accident conditions. One t
diesel genemtor is comnon to both Units and is automatically transferred to the Unit which requizes actuation of safety features. The onsite d-c power system consists of a 125 volt system. The system is divided into 3 groups, and each battery has its own battery chargers and switchgear. The batteries have the capacity to supply their loads for the time dumtion required, even without allowance for the diesels immediately relieving sane of the load.
Dr. Okrent asked what happens if, in a seisnic event, both tractors indicate that them is a IDCA? Nielsen indicated that whichever Unit receives its accident signal first will obtain the load fmn the swing diesel. After additional discussion, Okmnt asked if anyone has looked at the mliability of this situation, and does one Mve the necessary reliability? He further stated tMt he felt tMt the staff should look in detail at the design of everything that one needs to function in onfer to get onsite power (both a-c and d-c), given an earthquake large enough to Mve a masonable chance of losing offsite power. I'inally, Okrent ' asked if the staff had considered the possibility of sequential effects due to earthquakes, e.g., offsite power going off and on. Nielsen indicated, for the example cited, tMt once the diesels
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MAR.181975
, cme up to full speed (10 to 12 seconds), the offsite power source would be locked out. Mr. Ebersole mised some additional questions regartling the change-over from offsite power to the diesels, e.g.,
valve actuation. Nielsen responded to these questions for PGSE.
Finally, Ebersole mised the concern that the day tanks for all five diesels are supplied through a two-tank, two-pipe, two-electrical pump fuel oil system, and that the state of the entire fuel oil system depends on getting power to these two small pumps which nust cycle on and off frequently. Mr. Lindblad responded that the system meets the single failure criterion, and that he feels that it is adequately designed to perfonn its intended function.
lockout of Power to Mator@ated ESF Valves A letter on this subject frun Dr. Kerr of ACRS to Mr. Mantzing (dated January 14, 1975) had been distributed earlier in the meeting to the applicant and staff. The letter raised some questions regartling G-the proposed lockout of power to the above-mentioned valves.
T. Hirons of the staff indicated that the position stated in the Diablo Canyon Safety Evaluation Report was unchanged at this time. Mr. Lindblad stated that PGSE's position is that they prefer to maintain opembility of the valves frun the control recm.
Mr. Gormly of PGSE then began his presentation on this subject. He used a piping diagmm to indicate the nine valves which the staff had flagged with regarti to lockout of power. The most important of these are the single valves frun the refueling water storage tank to the safety. injection and RHR pumps. Seveml questions were asked during the presentation regartling the size of the valves, valve operators, annunciation of valve position in the control room, etc. Gormly detailed the information that would be available to the operator to indicate tMt one of these valves was closed, and the steps that the operator could take to open them. He indicated that they had mde no ccanprehensive evaluation of the probability of spurious closure of one of these valves.
Seveml of the questions in the ACRS letter on this subject were then discussed in light of the Diablo Canyon design. These included an evaluation of the probability of a spurious signal, time interval required for reactivation of valve opemtor after loss of power, question of whether signal lights are lost when the circuit bmaker in opened, reliability of valve indicators, etc. 'Ihe discussion concluded with Mr. Lindblad stating that the applicant would like additional time to consider some of the questions in the letter.
The staff also indicated that they would respond %rer to these questions.
a i
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a MAR.I O 1975
. Miscellaneous Questions (1) Mr. Ebersole ccmmented that the plant contains various hydrogen storage systems and lines throughout the plant. He brought up the general subject of hydrogen release and accumulation. Mr.
Gormly responded that they had taken this problem into account in designing the plant. With regard to hydrogen evolution out of the battery roces, Mr. Nielsen stated that they had studied this problem in detail (partly at the request of the staff), and that the analysis showed that it would take 28 days to w=0 ate enough hydrogen to approach the minimum explosive limit, assuming complete loss of ventilation.
(2) With Irgard to inservice inspection (baseline), Dr. Bush stated that the Units apparently meet the criteria set forth in ASME Section 11-1971; in this regard, he asked how this compams with the 1974 code? Mr. Lindblad replied that the amas of non-compliance with Section 11 of the 1974 Code am very limited IM N in natum. This question will be discussed in greater detail at a future meeting.
(3) Dr. Okrent asked if in the routing of electrical systems, am seismic Category I and non-seismic Category I lines ever placed in the same cable tmy or penetmtion? Mr. Nielsen replied tMt a
they are not. Okmnt then asked if there are possible modes of g) overheating for the non-seismic lines which could lead to a loss
[.'
of penetmtion integrity? After scme discussion, Okrent asked the applicant and staff to be prepamd to discuss this item at the next meeting.
Emergency Plan Mr. Shiffer of PGEE discussed the emergency plan for the Diablo Canyon Units. He indicated that in the development of the plan, primry considemtion was given to the Decmber 1970 AEC guide for the prep 1mtion of emergency plans for production and utilization facilities. The plan includes provisions for primry and alternate emery,ency control centers, notification of offsite state and fedeml agencies with responsibilities during an emery,ency, onsite first aid and decontamination facilities, and mergency mdiological mnitoring equipnent. Shiffer indicated that the plan describes a spectrum of accidents and the specific action Icvels to be taken for protective measures.
In the event of an mergency, the San Luis Obispo County Sheriff's Department is responsible for coordination of any initial offsite protective measures which may be mquired.
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MAR.Ig1975
- Dr. Okrent asked if PGSE had developed within their own procedures, the specific infomation, the instrunentation, and the evaluation of these readings such that the operator or some other responsible person could detemine the nature of the events, given sane postulated accident? In the question he included the range of situations discussed in Draft WASH-1400. Shiffer replied that their procedures did include specific offsite monitoring techniques, and procedures for interpretation of nonitoring msults, e.g., dose conversion tables. Considerable discussion ensued on this item, with Okmnt emphasizing that early wrning time of accident details was an important considemtion in Dmft WASH-1400.
Shiffer indicated that they have looked at high temperatum radiation monitors inside containment, and also the possibility of a detector outside contaiment looking at either the exterior concrete surface or at the liner at the containment equipnent hatch. However, he questioned the validity of the interpretation of data which might be obtained from such instrunents.
T. Hirons indicated that the staff is still reviewing this question, both in a generic sense and specifically, w
for the Diablo Canyon Units; a draft Regulatory Guide on post-accident instrunentation is currently being formulated. Okrent asked both the applicant and staff to be prepared to discuss this item at the next meeting.
Miscellaneous Questions (continued)
(4) Mr. Ebersole conndnted on the setting of valves in the RHR systs, i.e., the setting of valves to cope with the problen of pipe bmak with regarxl to the paths which the mter could follow. The question on this pertained to the fairly simple instruction on an FSAR drawing regarxiing adjustment and locking of a specific valve; Ebersole felt that perhaps this instruction should be expanded because of the number of possible fault situations. Mr. Lindblad replied that indeed nore detailed instructions are available for the operators.
(5) Ebersole asked about the intermediate comon C train in the camponent cooling m ter system. If a mjor leak occurs in this C train, how do you prevent the operutor frun simply drying up the system by pumping the alternate water inventories in the A and B trains into the sane fault? Mr. Gormly discussed the nonitors which would alam such a fault, and indicated that the C header would be isolated before any substantial loss in backup mter supply,had occurred.
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MAR. I 8 1975
- (6) Dr. Okant asked whether the water hanmer pmblems experienced at Indian Point 2 could be expected'to occur at Diablo Canyon? Mr.
Lindblad irdicated that both Westinghouse and PGSE am curmntly myiewing the installed Diablo Canyon system to see how it empares with the Indian Point situation. Okmnt further asked whether Diablo Canyon would be subject to the associated effect of contaiment liner heating that ar~==_nied the feedwater line mpture at Indian Pbint? Lindblad stated that he did not think so, and that Diablo Canyon has a different feedwater design in that welds am anoved fmm the in-diate ama of the liner plate.
(7) Okrent postulated a LOCA situation downstmam of the steam generator whem a two-phase mixture coming out of the vessel might lead to dynamic fomes, particularly in the steam genemtor. He asked whether Westinghouse had done any further ex mination of this question? Dr. Peacock indicated that Westinghouse had completed an analysis of the primary to secondary system interface in the y
steam genemtor; the analysis considemd the dynamic loads msulting fmn seismic fomes, blowdown, and various load cambinations. One conclusion of the analysis was that slug flow would not be pmdicted by the blowdown process. Peacock stated that this work was documented in a WCAP m port which was submitted to the staff over a year ago. Okrent asked the staff to check on the review status of this mport and conment at the next meeting.
(8) Okrent asked if the staff had reviewed the kinds of insulation used at Diablo Canyon, and examined the potential effects of insulation in the sump in the event of a IDCA? Ilimns indicated that the staff had mquested and mceived this infonnation fmn PGSE, and tMt we were still mviewing it for acceptability.
Okant asked for additional discussion on this at the next meeting.
(9) Okrent asked if it was planned to run the Diablo Canyon contalment in the purge node while the reactor is at power? Lindblad m plied that the purge valvrs would nomilly be closed. He further added that the purge valves have the capability of closing during a LOCA.
(10) Okmnt asked whether the question of unacceptable fomes on the check valve seats in the secondary system Md been examined?
Mr. Lindblad msponded tMt this question had been analyzed by their consultant (Nuclear Services Corpomtion), and tMt the valve integrity was found to be satisfactory; he also stated that
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T MAR. I 81975~
! the staff had mviewed the analysis and found it to be acceptable.
Mr. Ebersole pursued the discussion with m garxi to one of the check valves experiencing steam flow mversal; he asked whether the discs will survive the tremendous impact upon closure. Mr. Allison of the staff stated tMt the discs would be deformed but not broken. In m1ation to this problem, Ebersole suggested that a pipe break in the vicinity of these valves could indeed effect the valve in the opposite line and possibly msult in the blowdown of two steam generators. Lindblad stated that their analysis had shown that the second valve could withstand the failure of the first line. Peacock emphasized that protective functions have been incorporated in the design to assure that only one steam generator blows down.
_ Conclusions Another Diablo Canyon Sifw=nittee Meeting will be scheduled once the evaluation of Geology and Seismology has been completed. 'Ihe staff plans to complete this evaluation sometime in May of this year.
&ns Dr&d-),
u 3.3
'Ihomas J. Hirons
@N)
Light Water Reactors Project Branch 1-3 Division of Reactor Licensing Enclosums:
1.
Proposed Agenda 2.
Attendance List cc w/ enc 1:
Mr. John C. Warrissey Philip A. Crane, Jr., Esq.
Andmw J. Skaff, Esq.
Mr. Prederick Eissler Ms. Elizabeth E. Apfelberg Ms. Sandm A. Silver Mr. John Forster Mr. Ionnie Valentine Mr. William P. Comwell '
Mr. W. J. Lindblad Mr. J. W. Dorrycott c-
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ENCIDSURE 10.1 i
PROPOSED AGENDA DIABLO CANYON UNITS 1 & 2 SUBCOFD11TTEE MEETING FEBRUARY 18-19, 1975 - SAN LUIS OBISPO, CALIFORNIA-PRINCIPAL SPOKESMEN:
W. J. Lindblad - PG&E, Project Manager Tom Hirons - Project Manager, Reg. Staff TUESDAY. FEBRUARY 18, 1975 (30 min.)
I.
Executive Session - CLOSED -(8:30 a.m. - 9:00 a.m.)
(5 min.)
II.
Introductory Statement (PG6E)
A.
Brief Description of Site Location / Layout B.
Construction Status - Units 1 & 2 C.
Fuel Load / Operation Schedule (15 min.) III. Project Review Summary and Status Report (DL)
A.
Update on M*.,1974 SER Unresolved / Outstanding Items B.
Resolu(ion / Status of ACRS CP Letter Items EC (2 hrs.)
IV.
Site Characteristics l
A.
Geology / Seismology (DL/USGS) 1.
Detailed Status of DL Review 2.
Applicant Presentations (PG6E) a) Basic Geologic / Seismic Data b) Vibratory Ground 'Hotion c)
Surface Faulting d) Offshore Seismic Interpretation Program e) Determination of SSE and Seismic Design "g" Value for Site (30 min.)
B.
Tsunami Analysis (Model/ Analysis / Review Status) (PG&E/DL)
(15 min.)'
C.
Tornado Design / Criteria 1.
Applicant Presentation (PG6E) 2.
Conformance to Current Criteria (DL) 3.
Systems for Safe Shutdown Weakly Protected (PGEE/DL)
(15 min.)
D.
Other Site Characteristics 1.
Meteorology Hydrology, Demography, etc.
(PG&E)
(1 hr.)
V.
Seismic Design (PG6E/DL)
A.
Design Criteria for Containment / Major Components B.
Significant Changes in Design Since CP Stage C.
Design Criteria / Qualification Requirements for Safety-Related Instr.
D.
Stress Levels at 0.4g/0.5g/ Higher "g" values 1.
Safety-Related Systems Most Vulnerable to Seismic Events PossibleEffectofNon-SeismicClassISystemFailureon E.
Safety (15 min.) VI.
Experimental Confirmation of Seismic Design Aspects (fGr6)
(30 min.) VII. Scismic Scram (FG6E/DL)
Existing Desi ns/Available Methods A.
S B.
Experience & Reliability Considerations pgg A43
..i
. F,coposqd Agenda - Diab' )
, T 1/28/75 SUBC(MMITIEE CAUCUS - CLOSED SESSION
.(15 min.) VIII. Systems Interactions (PG&E/DL)
(reference letter, dated 11/8/74, WRS to Muntzing)
Adjourn meeting at 7:00 p.m.
WEDNESDAY - FEBRUARY 19, 1975
( 30 min.)
I.
Executive Session - Closed (8:00 a.m. -8:30 am)
(30 min.)
II.
Reactor (PG6E)
A.
Brief Description of Major Features / Comparison with Existing Designs B.
ECCS/LOCA - Appendix K Evaluations.
1.
Unit 1/ Unit *2 Results - Comparison with Existing Designs 2.
Limiting F calculated for Unit 1/ Unit 2 3.
Status /Sch dule for Completion 9
C.
Power Distribution Control Method - Ex-core /APDMS/
COAC (PGE/DL/W)
D.
Significant changes in Design from CP Stage E.
Status of 17x17 Verification / Review (15 min.) III. Electric Power Systems (One Line Diagram)
(PG&E)
A.
Offsite Power B.
Onsite Power C.
Emergency Power D.
Reliability Considerations - Diesel Qualifications (15 min.)
IV.
Emergency Plan (PGhE)
(15 min.)
V.
Industrial Security - Closed (PG&E)
(??
)
VI.
Resolution / Status of Generic It. ems (PG&E)
A.
List ??
B.
List ??
C.
List ??
(20 min.) VII.
Plant Items (PG&E/DL)
A.
Brief Description of Plant / Layout C.
Major Design Changes Since CP Stages C.
Lessons Learned from Operating Experience /Related Design Changes VIII. Lockout of Power-Operated ESF Valves (PG&E/DL)
Adjourn Meeting at 2:00 p.m.
-___________-_.._;___=______ _. -
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ENCIDSURE NO. 2 ATTINDANCE LIST i
DIABID CANYON ACRS SUBC0ttTITEE MEETDG
\\
l ACRS Dr. D. Okrent Dr. S. Bush ACRS CONSULTANTS Dr. B. Page* (Stanferd University)
Dr. G. hyson * (Stanford University)
Dr. M. Trifunac* (california Tech.)
i Dr. M. White (University of Massaclusetts)
Mr. K. Steinbrugge* (University of California)
Mr. J. Ebersole** (on leave of absence fran TVA)
Mr. E. Koffman (Ios Angeles Water S Power Department - Retired)
\\
Dr. S. Siegel (Atomics International - Retired)
ACBS STAET J. Conran i
PACIFIC GAS AND ELECTRIC COMPANY (IGSE)
W. J. Lindblad J. B. Hoch R. V. Bettinger W. K. Bnmot l
H. J. Gamly E. P. Wollak V. J. Ghio D. Nielsen R. A. Young R. R. Pray J. C. Carroll J. R. Herrera P. A. Crane
- D. Sullivan R. Ramsay J. Shiffer R. Patterson i
i 4
l pe3R a,'pl**
_i
. FGSE CONSULTAN1'S Dr. R. Jahns* (Stanford University)
Dr. S. W. Smith * (University of Washington)
Mr. D. H. Hamilton * (Earth Sciences Associates)
D. J. A. Blume* (John A. Blume S Associates, Engineers)
R. r,allagher* (John A. Blume S Associates, Engineers)
D. Jhaveri* (John A. Blume S Associates, Engineers)
.i Dr. L. S. Hwang* (Tetra Tech, L wricated)
WESTINGHOUSE Dr. D. W. Peacock Dr. T. C. Essalman Dr. Chi-Wen Lin Mr. J. W. Dorrycott Mr. A. J. Abels
'I N NRC - STAET T. J. Hirons D. P. Allison O. D. Parr R. C. DeYoung*
J. C. Stepp*
R. B. McMullen*
R. B. Hofmann*
W. P. r,amill
- H. R. Denton*
L. G. Hulman*
M. L. Fliegel*
K. K. Kapur*
L. Shao*
J. R. Tourtellotte*
I i
I t
r
- : s
s
~
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USGS J. Devine*
F. McKeown*
H. Wagner
- R. Yerkes*
GDERAL PUBLIC Attendance by the general public ranged between 10 and 30 people, depending on the particular subject being discussed.
be
- Denotes attendance on first day only.
C* Denotes attendance on second day only.
e O
e I
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(
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/
ph Distribution:
Docket Fil R. Tedesco NRC PDR V. Stello
~
Iocal PDR R. Ma mary NRR Reading (M. Gruff)
H. Denton R. DeYoung V. Benareya V. Moore
- c. Img D. Skovholt J. Kastner D. Muller G. Lainas R. Denise D. Ross K. Gollce T. Ippolito G. lear J. Knight W. Butler S. Pawlicki J. Stolz L. Shao R. Clark B. Grimes T. Spies W. Ca=n411 D. Vas<:alln R. Rallard K. Kniel P. Fine O. Parr T. Novak A. Schwencer M. Spangler R. Schemel EP Project Manager - W. Ross D. Ziemam Attorney, ELD p
P. Q)11 ins E (3)
R. Purple V. Wilson G. Knighton ACRS (14)
G. Dicker Project Mana6er -
T. J. Hirons B. J. Youngblood IWR l-3 Readmg W. H. Regan, Jr.
IWR 1-3 File R. Voll e D. P. Allison W. Houston J. C. Stepp S. Varga R. B. McMullen R. W. Klecker R. B. Hofmann F. Scu A L. G. Hulman K.
K'. Kapur M. L. Fliegel J. R. Tourtellotte
,i"
,s g.f p o r k w e 'JII A ~33 C
I' l
C Y'
pp 1 B M g((
M Lee V. Gossick, Acting Deecutive Director for Opemtions dW
'HIPJJ: Edson G. Case, Acting Director of Nuclear Peactor Pagulation gcsa STA'IUS REPORT ON SELECTED LICDISDE CASES Enclosed are the brief weekly status su::maries for the week ending Itirth 15, 1975, for:
Allens Cmek 1 S 2 Diablo Canyon'1 S 2 Indian Pbint 3 Perry 1 S 2 Originalsigned by Roger S.Boyd A. Giambusso, Dim ctor Division of Reactor Li m irg Office of Nuclear Reactor Regulation
Enclosures:
As stated above a!IRV!!
Distribution:
Docket File (50-466 50-467)
Docket File (50-27 8 50-323)
Ibcket File (50-286)
Docket File (50-440 S 50-441)
NRR Reading (M. Gruff, Rm.188)
IRR 1-3 File IRR 1-3 Reading D3 Case FSchroeder AGiambusSo (7 rh ' f RSBoyd
, j //
.,../ Cl VAMoore
) " ' I ~'
RCDeYoung INu11er
,v devas elln Y
WRButler ODParr MJ0estmann
-TJHirons J0rndoff DPAllison
.D. _ J_
AD/NRR RL:
1-3 1
o,r.c.,
Oh ODParr:pga so
._EGCase eo.m..,
^
3//7/75 ~
3/jf/75 3/D/75 3/ /75
- Foran AEC,318 (Rev. 9-53) ABCM 0240 W u. s. eovsnmusar rasanne orrecas sera.sas-see F o m. rt.- 391 l'
A-Se A -39
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i t
l STA'IUS REPORT IUR WEEK ENDING MARCH 15, 1975 PACIFIC GAS AND ELECIRIC COMPANY DIABLO CANYON UNITS 1 AND 2 DOCITT NOS. 50-275/323 There has been no significant change in status since last week.
I I
The current status is'sumarized below.
f We arxl our consultants, USGS, were unable to reach a favorable conclusion on the offshore fault with the present information and we are awaiting additional information frun the applicant.
Assuming that the infornation is received in early April and that we and USGS make a favorable conclusion on it, then we could have a July Ibll ACRS and a February 1976 decision date.
6 The applicant presently estimates an October 1975 core load.
This will probably slip to January 1976. However, it still appears that resolution of this problem is likely to delay the actual core loading. Accordingly, every effort will be made to expedite the review, SER Supplements, ACRS meetings and hearings after the information is received.
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