ML20234D449
| ML20234D449 | |
| Person / Time | |
|---|---|
| Site: | 05000000, Grand Gulf |
| Issue date: | 02/14/1974 |
| From: | Obenchain C AEROJET NUCLEAR CO. |
| To: | Lainas G US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML20234A777 | List:
|
| References | |
| FOIA-87-40 NUDOCS 8707070212 | |
| Download: ML20234D449 (3) | |
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04Ho rALLS, IDAHOhjh @ llC) i N February 14, 1974 3 S. ATOMS Ud.F.3Y COMM.
ADVISORY COMMITTEE ON 1
REACTOR SAFEGUARDS Gus Lainas Chief, Containment Systems Branch Directorate of Licensing I
U.S. Atomic Energy Commission Washington, DC 20545 RATIONALE FOR ANC VENT CLEARING 1!0 DEL NODALIZATION - Oben-5-74 Pursuant to your request, this Ictter documents the rationale for choosing a six-node representation of the annulus and horizontal vents in the ANC vent clearing model for a Mark III horizontal vent system.
The present ANC model for the Mark III vent c1 caring action is based on a need for representing independent action among the three horizontal vents which lie in a vertical plane.
Three vent nodes plus three annulus nodes in the present model detert:ine the pressure drop across the vents. A seventh node is used to model only the most basic dynamic behavior of the wet well. Other pertinent aspects of the model are that the nodes are modeled in one dimension with no area changes within any node, and the fluid is considered incompressible and iso-thermal.
Irreversible losses due to expansion, contraction, an'd turning are duly accounted for.
The six nodes chosen to model the annulus and three horizontal vents are the minimum required to model each vent individually and provide necessary detail of pressure distribution in the annulus to adequately describe the driving pressure on each horizontal vent.
The' minimum required noding was used in order to keep the model as simple as possible and minimize computation time. Nodalization studies have not been made to demonstrate that six vent system nodes give a con-vergent solution, ie, that precisely the same results would be calculated if one were to use, for example, 10 or 20 nodes. However, we feel confident that six nodes give adequate representation of the vent system and that further nodalization is ur.*ccessary for the following reasons. A segment of the vent system consisting
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of three horizontal vents stacked vertically is modeled in one dimension with no area changes within nodes and with an isothermal, incompressible fluid. Therefore, any given length of pipe has zero velocity gradient along its axis. Further i
subdivision of any annulus or vent node (the wet well node is huge in comparison and any node effects will be much smaller there) yields no new information about the velocity in the pipe.
The same holds true for the acceleration of 1
the fluid in the pipe, as observed from examining the continuity equation between any two points along the node.
Since p
=p
= constant, A
=A
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y 2
y 2
dV dV y
2 constant, and p A V =pAV, then V =V2 ""d dt " dt yy7 222 y
area change or a density gradient, then one would have a velocity gradient along the pipe and finer nodalization would show some effect.
The only gain one could realize by additional nodalization in the vent clear-ing model would be to account for the two-di=cncional effects at the junctions of the vents with the annulus.
However, this is beyond'the point in question, and a sufficiently large irreversible loss coefficient would mask the two-dimensional effects and yield conservative results.
Al so, the transient time of the fluid surface through the branch points is small in comparison to the total travel time through the whole vent system; hence, one would not expect much gain in a different type model just for the purpose of looking at flow at the branch junction in more detail.
The !brk Ill vent flow calculations use a different model than the vent c1 caring calculations.
The ver.t flow model does include the capability to vary the number of flow elements or nodes in modeling the vent system. A minimum of ten nodes is required and a maximum of 50 nodes allowed for modeling the three-vent system.
The two-phase flow equations include air flow, assume one-dimensional compressible flow with quality change, and assume steady-state theory.
Nodali-zation studies have been carried out with this model.
Three cases were run in which 10,22, and 40 nodes were used in successive runs to model the annulus and three horizontal vents.
This study shows virtually identical results for peak dry well pressure, integrated vent flows at the time of peak pressure, and for time-dependent plots of calculated dry well and wet well pressures and temperatures for the three cases investigated. Based on these results, it has been concluded
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that use of the minimum allowable ten nodes to represent the vent system provides a converEent solution for the vent flow calculation, ie, no significant nodaliza-
. tion effects appear when additional noding is utilized.
In summary, although nodalization studies have not been made for the vent clearing model, it is believed that six nodes give adequate representation of the annulus and vent systcm for the reasons given.
Further confirmation of this conclusion is expected to be obtained by comparison of calculated vent clearing behavior with experimental data from the General Electric Mark III Confirmatory Test Program.
Ibac C. F.'Obenchain kr cc:
S. H. Hanauer, DRTA E. G. Case, L A. Giacbusso, L J. M. Hendrie, L V. Stello, L R. L.. Tedesco, L w/attch D. F. Ross, L T. M. Novak, L J. T. Telford, L L. E. Sullivan, L w/atteh J. Kudrick, L w/attch D. E. Solberg, RS D. Pomeroy, R0 L. S. Tong, RSR, w/attch W. W. Bixby, RSR w/attch
- R. F. Fraley, ACRS w/sttch (3)
P. E. Litteneker, IDO w/attch C. E. Gilmore, IDO w/attch E. R. Christic, ANC R. J. Schultz, ANC w/attch O
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February 12, 1974 l
D. Okrent THEOFANOUS* COMMENTS OM GRAND GULF On February 5,1974, I received a telephone call from Dr. Theofanous in which he identified the following list of items as still open to resolution:
A.
ECCS 1.
GETAB calculations for Grand Gulf 2.
Jet Pump data quality at the ouetion 3.
Inertia effects and asymmetries in the downeomer node 4.
Adequacy of long term model for water inventory 5.
System effects and modeling for short and long term models 6.
System effects for application of F12CNT data 7.
Signifies u:e of dissolved gases on lower plenum fisshing 8.
Evaluation of design margins for blowdown forces on internals (acoustic decompression) 9.
Adequacy of the Moody model and current noding for break flow (possibility of the discharge coefficient (c) being a function of time or e >1.0)
B.
Containment 1.
Adequacy of blowdown calculations for determining containment design criteria 2.
Adequacy of noding and added mass calculation for the vent clearing model 3.
Tent clearing for large scale tests do not compara as closely with predictions as do the small scale tests 4.
There is very little fundamental understanding of the initial air sweeping transient for the Mark III containment as well as all previous pressure suppression containments (Mark I and II) 5.
Quantification of splashing (also relevance of Swedish tests) 6.
Experimental information on pool stratification and effects on containment pressure Filed: 1-Orand Gulf 2-T. Theofanous, Cons.
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Flow regimes at injection points (vents and relief valve discharge) 8.
Experimental and theoretical information on loadings due to poo?, splashing Dr. Theofaneus plans to visit GE and discuss these matters prior to the Mtreh 4, 1974 meeting of the Grand Gulf Subecamittee.
J. C. McKinley Senior Staff Assistant ec: ACRS Members T. Theofanous omcE>
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ELND GULF SUBCGt(ITTEE MEETING, JANUARY 17-18,1974, 3AN JOSE, CALIFORNIA Listed below are specific aspects of the topics to be considered at the Grand Gulf Subcommittee meeting, January 17 and 18. Other aspects er topics may be brought up by the Subcomunittee or its consultants.
1.
Beismic design bases Description of the safe shutdown earthquakes a.
b.
Extent of the New Madrid earthquake sone z
2.
Hydrogen generation and control Bases for hydrogen evolution rate (Regulatory Staff) a.
b.
Possible mechanisms which could lead to hydrogen saaeraties beyond that calculated by the applicant, for a double-ended pipe break
)
(Regulatory Staff and applicant)
)
Reliability of the system proposed for coping with hydrogen (Regu-c.
latory Staff) d.
Automatic or manual activation of hydrogen control system (Reguia-tory Staff and applicant) j Capability of drywell, etc., to withstand various hydrogen burning
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events (Regulatory Staff) 3.
Uncertainties in power and power distributes (suclear uncertainty factor)
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4.
Loss of coolant accident and'ECCS performance s
Evaluation of LPCI capability (without any consideraties for core a.
sprsy) (Regulatory Staf,f) b.
Means to ascertain potpatial blockage of core spray mousles ever the reactor's lifetime (Regulatory Staff and applicant) c.
Degree to which blockage of core spray nossles is tolerable (applicant and Regulatory Staff) d.
Blowdown forces resulting from a IACA -- any unknowns (Regulatory Staff)
Independent confirmation of the analyses by the Regulatory Staff e.
f.
Possible future improvessents in ECCS (include flow rate comparisons of the several systema for BUR /4, 5 & 6, and reliability considera-tions (Regulatory Staff and applicant) 5.
Turbine missiles (turbine orientation and possible missile trajectories) 6.
Reliability of new control rod design S
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Pressure Suppression System Porces on structures above the pool (Regulatory Staff) a.
b.
Extent to which experimental corroboration is required (1) Prior to issuance of a construction permit (Regulatory Staff)
(2) Prior to some later milestone (Regulatory Staff)
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Possible dynamic effects in the suppression pool resulting from l
c.
relief valve discharge (Regulatory Staff and applicast)
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d.
Role of non-condensables and other phenomena in relief valve I
discharge to the suppression pool (Regulatory Staff and applicant)
Possible dynanic loads on containment or drywell well, etc., from e.
relief valve cperation (Regulatory Staff and applicant) f.-
Detailed description of the dynamic phenomenons important te the action of the suppression system in s IDCA (Regulatory Staff and applicent) 3 Role of non-condensables in item feebove (Regulatory Staff and applicant) h.
gffects of solid walls on the results of tests performed in the segment of a full-scale experimental facility (Ragulatory Staff and applicant) 1.
Possibility of pool oscillations permitting an intermittent bypass path for stema from t.he drywell asesping into the containment. Are the taperiments adequate to study this phenomena or circumferential save effects? (Regulatory Staff and applicant)
- j. Role of non-condecsables in the Moss Landing and qued Cities test results k.
Drywell bypassing considerations.
8.
Resolution of generic items (refer to the December 18, 1972 ACRS report and subsequent ACRS reports).
9.
Matters identified in the Regulatory Staff Safety Evaluation Reports a.
Seismic classification of various systems and structures b.
Quality group classifications c.
Stress limits and design loading combination d.
RFCs diesel generator reliability e.
Radionuclides concentrations in the refueling water storage tank f.
Freon decomposition potential g.
Main steamline isolation k.
Ms1 positioning of control rod (s) 1.
Reactivity reduction following a reactor trip orFICE >
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- 10. Seismic design considerations:
a.
Now is a representative set of stresses obtained for a given direction when more than one mode shape is consideredt b.
How is relative motion treated for " rigid" members (base slab and walls)?
c.
Is the use of " beam type" mode treatment completely acceptable?
- 11. Environmental considerations:
a.
Potential doses to water drinkers downstream from Grand Gulf from all muclear plents upstream of the user (applicant) b.
Effects of failure in the radwaste storage system (Regulatory Staff) c.
Consideration of the effects of mining, preparation, and process-ing of fuel and radioactive weste storage (Regulatory Staff) i s
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January 15, 1974 Dictation Over Telephone From T. G. Theofanous on January 11, 1974 1.
What is the limit of small break sises as determined from GEILt 2.
Does the use of GEIL result in earlier dryout of the upper oore during a typical BR DBAf Again, for a typical DBA it has been shown that the midplane peak clad temperature will eventually overtake that of the upper core resulting in 140*F dif forence in calculated peak clad temperature. Provide justification that this is a general conclusion spanning conditions of all break sizes in ECCS performance.
3.
Present updated calculations (use GEIL, film boiling and current ECCS transfer coef ficient) for a Grand Gulf DBA, intermediate breaks and a small breake 4.
.;Biscuss in detail the physical phenomena and system effects occurring throughout each one of the calculations presented in Question 3.
In particular sever the details of interfacing the short term to the long term code for the DBA and intermediate breaks.
5.
Provide jaa*.ification the t.he raficed calculation give rise to conservative reflood times.
6.
Provide ficws, thermodynamic conditions and levels for the short term transient of the nodes 1, 5, and 7 as shown in NED0-10329.
7.
Provide jet pump experimental date with steem quality at the auction.
8.
What system effects tests have been performed to assure that an accurate overall understanding of the whole sequence of accident phenomena is provided by the GE calculational models.
9.
Provide justification that the simple geometry separate effects tests of level swell constitutes a sufficient basis for the lower plenum flashing calculations as applied by GE to the 14CA analysis 4
(i.e., including the resultant film boiling coefficient).
l 10.
The description of the long-term model given in NEDO-10329 is geared to a small break analysis. Provide a similar description geared to j
its use in the BCCS performance description of a DBA and an intermediate 1
site break.
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h spray heat transfer coefficient as deduced in E 30 10329 Supplement 1, are not conservative in view of the sensitivity of peak chad temperature to these seefficients. The surrent task of fundamental understanding in this area provides GE's justification for the current uses.
12.
h t wetted-ean to falling film best transfer coefficient is utilised in evaluation Yamanoueni's correlation. h t is the basis for the choice?
I 13.
What are possible interaction effects between the flooding and
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spraying ECCS modest i
14.
Discuss the wall effects on the initial transient of air /steem venting into the Mark-III simulation containment.
I 15.
Provide dynamic loads on Mark-III structure resulting from relief valvs discharge (initial transient).
16.
Esp)Ain the basis for assuming uniform distribution of core spray at LOCA conditions. In particular explain how the Monticello core spray 44,stribution tests were conducted and the basis for simulating steam currents in the upper plenum in steam separator regions.
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CFA'ID GULT NUCIEAR STATICN IMTS 1 & 2 SLECOWITTEE J7CKSON, MISSISSIPPI
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1.0 ATTCri E j
/CRS Air D. Okrent, Subcomittm Chairran G. Owsley - L M. Bender. (Dec. 2L only)
D. E Moeller G2EPAL ELECTPlc CD5'N4Y B. M. Pace, Consultant G. A. Tirrrwon, Consultant R P. Barr J. T. Wilson, Consultant A. J. James (Dec. 21 anly)
Z. Zudans, Cbnsultant L. J. Sobon W. A. Burns, Staff MISSISSIPPI TU ED & LIGiff COMON?Y 1A100% PCh.Ut CORPORATIm H. Carver (Dec. 21 only)
M. B. Dobrin, Consultant R. J. Conlon, CorAultant (Dec. 21 only)
C. O. Durhan, Jr., Consultant L. T. Dale (Doc. 21 only)
T. II.11abermas (Dec. 21 only)
W. E. Edoo R. L. I! ails T. E. Tblicwill, Consultant (Dec. 22 onl-C. T. Lefevre (Dec, 21 only)
P. J. Ibit, Cbnsultant (Dec. 22 only)
M. C. Matricrly (EO. 21 only)
C. N Hutchinson (Dec. 21 only)
A. Sanver (Doc. 22 only)
A. S. McCurdy (Dec. 21 exily)
R. A. Schnalble J. P. Mcreughy C. A. Thcrpoon (Dec. 21 only)
A. PtKeio:wf J. J. Tkacik W. L. Nail N. L. Starpley L. StxIbeck (Doc. 21 only)
R. C. Travis, Attorrey (Dec. 22 only)
PUBLIC-AT-LVtrE Name Representiner City & State J. L. Looker Gulf States Utilities Beau out, Texas Donald A. Garrett Ganma Industries Daten Tbuge, La.
J. A. Veitzer Gulf States Utilities Beatrout, 'htxas
$5.Pruss'an Ebasco Services N.Y.
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- H. D. Richardaan Nuclear Systers, Inc.
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9 OFICIAl. USE OO kdh[A J Grand Gulf Subccrrtittee Meeting 2-V
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( (MDtes W. A. Burns, the designatexl Federal Goverrrient enployee, wasp :
' Trosent during this entire meeting of the ACRS Grard Gulf Nuclear Station; h Units 1 and 2 Subcrmittee. A notice for this recting was published in the Federal Rejister at 38 33793 en Decair.r 7,1973, in acecrdance with applicable provisions of the Federal /dvisory Cartnittee Ict (Public Itiv 92-463). I:xecutive Sessions held at the brqinning of the necting on each day ard durire the meetire of D3cxrfer 22, as well as a session with the Regulatory Staff and 1.pplicant, held on Decarter 21 for tM purpose of discussing matters relatad to plant security and prevention of industrial sabc* age, were closed to the public under the authority of Section 10(d) of the Act. We place of the necting was chwyd frm the Circuit Cburt-rom, Hirds County Cburthouse, President and Pascacaula Streets to Chancery Courtrom No.1, Hinds County Chancery (burt nuildiwr, 316 South President Street, due to lack of availability of the facilities noticed in the Federal Deqister (Attachmnt D)]
2.0 IIF50DLCTION Wis second necting of the ACRS Subccmittee on Grawl Gulf Nuclear Station, Units 1 and 2, was convened in Jackson, Mississippi, for the purrxme er cmtinuing the ACRS review of the application of tk Mississioni Power ard Light Crmipany for a pemit tc constnet the reard Gulf Nuclear Station.
Fbilowirc a visit by the Sulxrreittee to the site of the procosed niant durirn the nnmity of Dcocrter 11, a public mootino of tk Subocmittee van conducted durirn the afternoon of Decenber 21 and during the rerning of Decorder 22. A closed meeting was held with representatives of tk Requia-tory Staff ard Applicant on Dcotr.ter 21 frm 3:44 p.m. to 4:18 p.n. for the purpose of discussing mattern related to plant security and measures to prevent, or to mitigate the consequences of, industrial sabotage.
An oral staterent tasreceived by the Subocrrrdttee frm a rmber of the public, tir. Dale Wallace, et 10:58 a.m. on Deetriber 22. We transc ript of tir. ; allace's statcrent is included in ATDme.T F to these Minutes.
3.0 E'XDCL7PIVE SESSION (Closed)
Chairran Okrent called the meeting to order at 1:35 p.m. on Decerter 21 and reviewed with the other naribers ard consultant Dr. Zudans of the
<,94nnmunittoe the proposed two-day agorda (ATIACI!CC B) for the purpees 5
C of hining a desired order for presentation / discussion of subjects b itsuns atrd establishing a desired depth of review of each in the ligh$i..e,;
bof information broucht to the attention of the Subocrrrittee during thet '
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Chairman Okrent called the meeting to order at 1:46 p.m. and informed the attendees of the rules of procedure and order of consideration of agenda items. He noted that no written statements had been received from members of the public, and there was no response to his invitation for oral statements. Following these introductory remarks, the Sub-committee proceeded with its consideration of items on the agenda.
4.2 Agenda Items 4.2.1 Licensing Review Status Mr. Owsley, DL, summarized the status of the Staff's review of the Grand Gulf application, noting that:
o The review of matters related to site seismicity and containment design is incomplete.
o Review of other matters is nearing completion, and it is expected that the SER will be issued in mid-Januny 1974.
I o Staff attendance at this meeting was limited in accordance with the proposal of A. Giambusso (ATTACHMENT E) and additionally by transportation difficulties, which preventud the attendance of Dr. K. Bapur, the Staff specialist in seismic design of structures.
o A principal concern and effort of the Staff has been the determination of the southernmost extent of the New Madrid carthquake zone.
o The review of containment design is receiving particular emphasis because the Grand Gulf application represents the first proposed use of the G.E. BWR/6 - Mark III combination. The initial design submittal for the containment was considered to be unacceptable by the Staff because of assumptions related to reduced fission-product raileases and because no provisions were included for con-trol of post-LOCA, metal-water reaction hydrogen. The design was based upon Applicant analyses of the expected performance of the BWR/6 core. A new design, including a hydrogen mixing system and enclosure building, was subsequently proposed, and final design
- information was submitted late in November. This is currentir being reviewed.
Principal among current outstanding issues are matters related to 1.) the use of RHK System water for the con =
tainment spray system and 2.) the selection / identification of; containment spray actuation signals.
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.l The Staff has established no mechanism or rate for hydrogen o
generation from the metal-water reaction. However, it has g@
been acknowledged, for purposed of the Mark III review, that FA the release of hydrogen will not be instantaneous.
L o The arbitrary Safety Guide 7 assumptions of five percent of the clad reacting with teater and four-volume-percent hprogen as a lower f&ammability limit are being applied.
o The timing of actuation of the atmosphere mixing system is a t-matter of critical concern. The Staff has accepted a minimum of 10 minutes post-LOCA as a reasonable time delay to prevent steam bypass of the pressure-suppression pool. The blowdown phase is concluded earlier than 10 minutes post-LOCA.
the Staff position is that the lower flammability limit of hydrogen o
in the drywell would not be reached before 10 minutes. This amount bf hydrogen corresponds with about 1.3 percent metal-water reaction. The remainder of the hydrogen from the assumed five-percent reaction would be mixed with bulk contalamont stepsphere to achieve a hydrogen concentration of less than four voltsme p percent.
o The Staff prefers that the mixing system be actuated only on positive indication of the presence of hydrogen and with concur-rent indication of RFV depressurization and containment spray actuation / operation.
o An assumption inherent ir, the application of Safety Guide 7 criteria is that there has been some unspecified degree of de-gradation of the ECCS below that level of functional capability assumed for ECCS evaluation.
4.2.2 Hyd paen Generatio.n and Control I
Mr. J. p. McGaughy, Mississippi power and Light, and other representatives of the Applicant informed the Subcommittee on this subject as follows:
o The Grand Gulf Interim Acceptance Criteria (IAC) ECCS evaluation, with assumption of a worst-case single failure, shows a 0.01-percent metal-water reaction.
o tiith the assumption that all components of the ECCS fail except one LPCI pump, the percent metal-water reaction is 0.19.
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o Using a pack clad temperature of 2300F and clad temperature dis-tributions as required for IAC evaluations of ECCS, the time required to react five percent of the clad was determined to be about eighp hours; the time required to reach four-volume-cma > _.....pe rc ent-hy$ rogen -in-the dyywell vas mietermined-to be-about--one hour r-----
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- as o Five pereest: metal-water reaction corresponds to about 12-volume-percent hydrogen in the drywell and about 2-volume-perbent in the total containment atmosphere.
o Atmosphere mixing is provided by redundant pairs of 20,000 SCFM
&ns.
o he suppression pool bypass system (for atmosphere mixing) con-sists of three 24-inch-diameter penetrations of the drywell well, terminated on the outside with a Tee which is provided with four electrohydraulic, spring-closed ball valves,(two at each and of the Tee). The fans provide circulation through these openings.
The openings are arranged to provide a vortex circulation in the drywell even if one of the bypass penetrations should remain closed, but the mixing effectiveness of this arrangement has not been evaluated.
jir. Bender expressed the opinion that the reliability of the bypass valving system and the surveihnce requirements necessary to ensure the functional integrity of the complex bypass / mixing system would be matters deserving critical evaluation by both the Applicant and StaffJ o Diversity is employed in the design of pairs of pressure sensors (two-out-of-two) which will provide the opening signal. for each of the ball valves for vacuum relief purposes. The velves are opened and closed when the drywell pressure reaches minus 8.5 and minus 0.25 pai, respectively, with respect to the external pressure. The vacuum relief sensors have no effect on post-LOCA operation of the atmosphate mixing system, o the 10-minute, post-LOCA permissive signals for valve opening are generated by sensors for reactor vessel water level, drywell pressure, hydrogen, and containment spray system function. The installation will meet the requirements of applinable IggE s tandards. Valve positions will be remotely indicated / annunciated.
o If there were no necessity for diluting post-IACA metal-water-reaction hydrogen, the circulation fans would not be regsked med the suppression pool bypass system could be made less complex;. -
V o The complexity of the mixing system is not dependent on the L specified/ required hydrogen generation / dilution rate, but the recirculation capacity is.
omcE >
SURNAME >
DATE >
Form AEC.518 (Rev. 9-53) AECM 0240 e.o ess--na-st4as-a m-ets
l s
l Crand Gulf Subcommittee Meeting 4-p,"t e 'gpy.*
e To accommodate a five-percent metal-water reaction in 10 minutesh.s o
the mixing function would have to be initiated earlier or the T i' drywell volume would have to be larger or some combination of O ~?
i both would be required.
1 o Without recirculation, a five-percent metal-water reeceson would yield 12-volume percent hydrogen in the dyrwell. If this hydrogen should burn, the pressure transient would be less severe than for a LOCA and it is unlikely that any components of critical importance would be damaged. The transient analysis is presented in a GE topical report (MDO 10812).
In conclusion on this subject, Chairman ont requested both the Staff and Applicant to be prepared to address he next meeting 1.) matters reisted to the effect on percent metal-water-reaction of degraded con-ditions of the core and/or ECCS beyond the case of only one LPCI pump in operation (such things as structural deterioration of the core, time delays prior to actuation of the ECCS, etc.) and 2.) matters related to the need for providing assurance of the operability of core sprpys.
4.2.3 geismic Analysis of Structures In response to questions on this subject from Dr. 2ndans, Mr. R. L.
l Hails, Bechtel Power Corporation, and others representing the Applicant l
provided the following major points of information, o The bads fpr seismic design / analysis of Crand Gulf plant structures is given in the topical report BC TOP-4, Revision 1.
o A lumped unss codal analysis rather than the finite-element technique was used for the dynamic analysis of themmcontainment structure.
o The approach used consisted of a fixed-base analysia of the contaiturent structure (for guidance and check purposes only) followed by application of a damped-spring model which incor-porated the elastic properties of the soil, o The basid. procedure involves running a lumped-mass nodal analyeis for east-west and north-south SSE's, using the square root of the sum of the squares (SRSS) of the modal inertial forces.
The resulting average inertial forces are subsequently incorporated into a finite-element computer program to develop the related,
u stresses, which will themselves be quantified by the SRSS mathed.
y f, Note:
Dr. zodans empressed the opinion that use of the medal response method as described would be unacceptable that the derivation / treatment of stresses was not necessarily senservative; ~
and that a more asaservative approach would require taking into account the mode shape as derived from a time-hisotry medel.,7 sumur >
DATE>
Form AEC-318 lP.ev.9-53) AECM 0240 e.o
.es-to-sises-sims 1
Grand Gulf Subcommittee Meeting p--q, s, -
38-Other matters in regard to use of representative soil properties and eftests -
of relative motion between structures were explored, including matters sea l' isted to reistive stiffnssa of structurcs and bending moments (ovaling '
modes) in the containment building shelig sigs explored briefly/,ar were considerations relative to earthquake-generated motion of water in the fuel storage pool. The Subcommittee was informed thet:
Actual soil properties / variations are factored into the analyses, o
but the site is not soil-sensitive.
Relative motion is being considered in the design / flexibility analysis o
of interconnecting piping.
The stresses generated by ovalling modes were found to be small.
o The water in the upper pool will behave as a rigid body.
o Effects of wave action on the performance of components inanediately o
above the pressure suppression pool will be determined by planned G.E. experiments.
The experiments / tests will be designed to reflect effects on the full-scale Mark III over the full range of parameters of interest.
4.2.4 Environmental Considerations
(
Mr. McGaughy responded to questions from the Subcommittee in regard et i
waste handling and transportation, dcsas to the public from release of f
radioactive waste products, andemergency planning.
Principal items of in-formatbn were given as follows:
Liquid radwaste discharges from the Grand Gulf plant to the river o
will be well within the limits specified in 10 CFR Part 20, but I
total downstream doses to the public from the combined releases to the river from all sources have not been determined.
i The nearest downstream municipal water intake is at N.tchez, about o
40 river miles distant. However, inforua tion related to transport Times, type of municipal water treatment process in use and plans for emergency action could not be made available to the Subcommittee at this meeting.
o Background radiation data for the site will be collected and evaluated about three years prior to plant startup.
(
o The Applicant does not plan to become involved in fuel / waste trans.
portation matters to an extent beyond contracting with licensed facility operators.
OmCE >
- l.......
j EU AruAML >
DATE >
Form AEC418 (Rev.9-53) AECM 0240 o*o
.43-se-s wes.: us.s7s
l l
l l
Grand Gulf Subcommittee Meeting g.cw h vnl,.
t e Righ-level liquid radwestes will be chemically solidified prior
- fy74 p}."( q>"
to off-site shipment.
o About 100 shipments per year of solid / solidified radwaste are antic ipa ted. Between shipments, the wastes will be stored on site in a large vault in the Radwasta Building.
1 Matters relating to accidental release of (stored) radioactive gases, o
as described in the Final Environmental Statement, could not be re-solved at this meeting.
In conclusion, Chairman Okrent requested that the Applicant and Staff, as appropriate, be prepared to address at the next Subcommittee meeting those environmental matters for which information is lacking.
4.2.5 Site Geoloav/ Seismicity A review of the geology of the region was presented by Dr. C. Durham of Louisiana State University, and seismic matters were related by Drs. M.
Dobrin of the University of Houston (Vibroseismic investigations), R.
Holt of Weston Geophysical (historical setemicity) and F. Followill of the University of Mississippi (seismology,0 See ATTACHMENTS C and D.)
in general discussion and in response to questions from the Subcommittee and its consultants, the following principal points of information were given.
Localized disconthuities/ irregularities in the vibrossismograms o
can be attributed to variations in the pressure-wave transmitting properties of near-surface soil materials, as in the case of stream bed s, d ikes, levee s, e tc.
In the evaluation of vibroseis results, major attention is directed toward determining the continuity, or lack of continuity, of the strongest reflectors.
o Results of c oce drilling have generally confirced the geophysical interpretation of the vibroceiemograms, where such drilling was per-formed in regions of interest, as in the course of exploration for oil.
o Bibroseis anomalies / irregularities in regions of particular interest fj north of the site were bracketted approximately one to two miles
/ to the north and south by parallel lines for confirmation purposes.
/
No continuities (indtesting a possible fault) were developed.
l V
/
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omcr >
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suuwe>
j Dart >
I Form AEC,-518 tRev. 9 53) AECM 0240 e.o us-in-sicas. us-e7s
___________D
l l
l l
Grand Gulf Subcommittee Meeting '
p,y ;
e ne vibroseis investigations have tended to confirm that there see ".-.
geologic reasons for the confinement of major seismic activity efy '
the New Madrid type to the northern part of the Mississippi embey-V -
ment and that only minor quakes have occurred in the southern part of the embayment, as far south as Memphis.
The gradient of the embaydent starts to rise relatively rapidly at the boot of the Missouri, as compared with the gradient between Memphis and the boot. The maximum frequency of small quakes has been observed to occur in the boot of the Missouri at the hinge line, a line of change in structural contours. This supports the contention that a tiew Madrid type of earthquaka shoyld not occur south of about
- Memphis, o There is no known data or information that is in conflict with the Applicant's conclusions, and it is the opinion of tha Applicant that additional vibroseismic work / chart purchases should not be necessary to confirm the conclusions. A line was selected to pro-vide confitvation of a eeutbarneestboundary for possible faulting.
o In the absence of historical records / knowledge of the incidence of major earthquakes of the New Madrid type, the possibility of a major (Richter 7) sarthquake in the region of the New Madrid quake might be predicted on the basis of geological / fault / seismic activity information currently available for that region.
o For conservatism in design, the site of the New Madrid quake was moved southward about 100 miles for purposes of calculating the Grand Gulf SSE horisontal acceleration.
o Although the recurrence period for a New Madrid quaka in the New Madrid area is about 100 years, the recurrence period for a similar quake south of the Pascola Arch would be estimated at something on the order of 60 million years. De estimated recurrence period for an earthquake that would produce acc6terations at the Grand Culf site in excess of the SSE should be greater than 60 million years.
l In conclusion on this subject area, Mr. Owsley observed that the Applicant 1
had undertaken all of the studies and had provided all of the information previously requested by the Staff and that the total information was cur-rently in the process of being evaluated by the Staf f and its consultants.
Although no Staff conclusions could be made available to the Subcommittee j
at this meeting, Mr. Owsley noted that (draf ts? ce final reports relating
]
to setseology/ geology would be made available to the ACKS by the end of I
its 14Sth meeting.
l~
l 4
l l.
p i
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l OmCE >
SURNAME >
DATE >
Form AEC-M8 (Rev.9 53) AECM 0240 e.o
.es-to-suse.:.ss-os
Grand Gulf Subconunittee Meeting if.
5.0 METING WITH REPRESENTATIVES OF THE APPLICANT AND REGUIATORY STAFF TO 959tRh8 FiANT FHYSICAL SECURITY AND FEAIURES FOR THE PREVENTION OF INDUSIRIAL SABORGE
,(EP.ptina closed to the public)
Messrs Nail and Stampley* responded to inquiries from the Subcommittee in regard to design planning related to security and features for the preven-tion of sabotage as follows:
A security fence will enclose the main plant buildings (power block) o awitchyard and cooling towers. Entry thru the fence will be by way of a guard house and openings leading to the pump house.
o All equipment of critical importance to ph nt operation will be in the power block inside the security fence.
Access to the pump house will be through television-monitored o
openings which face the power blocks The security fence and access roads will be patrolled.
o The only entrance to the power block will be by way of a television-o monitored foyer protected by air-tight, missile-proof doors. All other doors in the power block are for egress only, the surveillance television display will be monitored in the guard o
house.
o Telephone, radio and microwave systems will be provided for com-munication with law enforcement agencies (six miles to nearest district highway patrol office) and Applicant headquarters offices.t.
Dec. ailed, formal arrangements for agency assistance remain to be worked out.
Validity of access cards will be checked by a computer system.
o o Vigorous employee screening procedures will be used.
the plant design / layout is being reviewed by a Bechtel security o
s pecialis t.
Attention is being given to security aspects of equipment placement.
o No individual will have access to the complete master security plan.
7 o Guards will be armed.
j,,
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- Mississippi Power & Light Company omcE>
$URNAMEk om>
i Form AEC-Sta (Rev. 9-53J AECM 0240 eso
.e4~ts-st44-1 e4s+ 7s
_____._________________________--_---____-_-_----------------J
Grand Gulf Subcommittee Meeting op. r, o
% 0.
6.0 MM_'TIVE SESSION / CAUCUS (closedl B %;Mg, hg TheSubcommitteemehbersandconsultants'reviewedtheinformationpresend by the Applicant and Staff to date, and they exchanged opinions in rega'rd -
to its adequacy and the need for additional information. The Subcommittee concluded that further review of geologic / seismic matters as st await receipt of the;8taff evaluation.
7.0 MIETING WITH THE REGUIATORY STAFF AND APPLICANT - CONCLUSION (meeting open
.to the public)
Chairman Okrant presented the following tentative agenda items for the next meeting of tae Subcommittee, noting that the list would be subject to modification by additional inpot f rom the Staff and Committee members and c onsultante.
_ Hydrogen Genetion and Control 1.
ECCS failure mechanisms and degradation assumptions,lgases applicable to the adoption of 10-minute,1.K7. metal-water reaction criteria and related requirements for the performance of the Grand Gulf containment atmosphope mixing system; comparison with licensing assumptions / require-ments imposed on other reactors -- both BWR's and NR's.
--- Staff.
2.
Bases fc reliability requirements to be imposed on the operation of the atmosphere mixing system, as applicable particularly to the dry-well penetration closure / fan system (s). --- Staff.
3.
Discussion of effects of hydrogen burning / detonation on drywell s t ructures / components. --- Staff.
Seismicity and Seismic Rejspoose 4.
Extension of review of site seismicity. --- Staff and Applicant.
5.
Extension of review of seismic response analysis of structures, particularly:
explanation of bases for use of the equations selected for computing o
composite-model damping coefficients Applic ant.
o methods / bases for conservative calculations of uni-directional (
stresses, taking into account more than one mode shape --- Staff and Applicant.
o bases for conclusion that water in the upper pool behaves as a /
rigid body Applicant.
&mcc ps es sment..of. t.k..ad.equac.y_pf analyses..o1 structurns..y oximat e...tp...tt a suppression poot surface.
Staff.
SURNAME >
DATE >
Form AIC-318 (Rev.9 53) AECM 0240 seo
.ea-ne-sues e4H7s I
Grand Gulf Subcommittee Meeting [qj;.
.LOCA/ECC8 W
General discussion of ECCS performance evaluation and magnitude of ".O 7.
LOCA blowdown forces. --- Applicant & 8taff.
8.
Review of blowdown force calculational uncertainties ethich may have a significant effect on important structural members. --- Applicant & Staff.
9.
possibility of core spray nossle plugging during the life of the plant. ---
Staff.
10.
Independent LOCA/ECCS analysis, with core spray alone and with LPCI alone. Means for ascertaining operability status of the core spray Staff and Applicant.
system.
- 11. Dynamic phenomena pertaining to behavier of the suppression system under po portulated LOCA conditions, with special emphasis on the effect of non-condensibles and the presence of solid walls on the results of full-scale pressure suppression system tests, particularly with usspect to the possibility of creating intertnittent release paths. --- Applicant.
- 12. Capability of proposed experimental program to resolve item (11)
Staff and Applicant.
matters.
- 13. Extent of reliance on experimental corroboration of the performance of the pressure suppression system.
Staff 14.
Review and comparison of Moss Landing and Quad Cities test results with respect to the role of non-condensibles. --- Applicant
- 15. Frequency response of the equipment used in the Quad Cities tests. ---
Applicant.
- 16. Discussion of ECCS improvements which reay be considered practical but which are beyond those proposed for the Grand Gulf plant.
Applicant and Staff.
h ironmental
- 17. Estimate of total dose downstream of the Grand Gulf plant including f
contributions from liquid radweste discharged from all upstream nuclear plaats.
Applicant.
[
t..
- 18. Description of downstream municipal water intake and treatment systems, plant discharge-to-intake transport time and means for emergercy com-musication and action to prevent use of non-Tech. Spec. raw water. ---
_ Anolicant.
omcE >
$URNAME>
DATE >
j Form AEC-S ts (Rev. 9-53) AECM 0240 eee
.ea-se-siens-a +is e7s
Grand Gulf Subcommittee Meeting rg.g IE Clarification of proposed design and operation of ga p[p..
3-19.
p system and estimates of site boundary doses resulting from routine E". ~'
operation and following postulated failure of critical components of '
the system.
Staff.
20.
Clarification of extent of evaluation of environmental effects, wti particular reference to mining, fuel processing and radwaste storage.
Staff.
Miscellaneous
- 21. Assessment of possibility of water hm=+r during pressure-t elief valve Applicant operation.
22.
Description in detail of all the phenomena associated with relief valve discharge incidents, particularly that portion of the transient which may be dominated by the presence of non-condensiblesen condensing surfaces.
Applicant.
- 23. Existence of significant dynamic loads (related to relief vatve operation) on the containment wall, drywell wall or any structures.
Applicant
- 24. Turbine missiles
- 25. Unresolved Generic Items applicable to BWRs (method of resolution)
Applicant and Staf f.
/,The meeting was adjourned at 12:00 N, December 22,1973J
)
ip r.
e omet >
SURNAkfE >
j DATE >
Form AEC.H 8 (Rev. 9 *,3) AECM 0240 e.o oes-to-si4ss-a sis-e7s
TRANSCRIPT CONTENTS
- 6q4, FRIn&Y. ** N @ ER 21. 1973
[
Lisemalag Review Status (Oralay).................
I L
e Setemicity..........................
9 o containment Design......................
10 o Hydro 8en Generation / Control.................
14 o Clarifications (McGoughy)..................
29 Hydrogen Generation / Control (McCaughy)...............
33 o Hydrogen Burning / Detonation.................
49 Atmosphere Mixing System Reliability.............
53 o
Postulated Events / Conditions for Increased Hydrogen o
Generation..
61 Se ismic Analys is o f S t ruc ture s (Ha ils )...............
66 o Rela tive Movement of S truc tures...............
76 o Dynamic Behavior of Fool Water................
79 o Banding Moments.......................
80 o Ef fects of Pool Turbulence / Waves on Structures........
81 Effect/ Treatment of soil Properties.........
88 o
o Con f i rma t ion o f De s ig n Ad equac y...............
91 Environmental Considerations (McGaushy)..............
95 o Dose Effects of Combined Flant Reinses of Liquid Wastes...
96 o Eme rge nc y As s is t a nc e.....................
99 o transportation of Radioactive Materials....,.......
102 o S olid Was te Ha nd ling.....................
104 219 o Release of Stored Gaseous Wastes.............
222 Dite Geology / Seismicity (McGaughy).................
110 i
o Geology (Durham).......................
113 o Vibrossismic Investigations (Dobrin).............
129 (Summary)........................
146 l
SATURDAY. DECEMBER 22. 1973 o His torical Seismicity (Bolt).................
152 e Epicenters / Magnitudes....................
153 o Focal Flame Solutions....................
155 e
5- -ary (Schnaible).....................
157 e Raplanation/ Clarification of Vibrosaismogram/
Discontinuities / Irregularities /Teatures (Dobria)......
161 194 e Seeps of Vibroseismic Invest 18ations (Durham)........
189 e
195 o Ef ame-Line/ Seismicity Ratationshies (Schmaible) 192 o Ea rthquake Prediction (Holt /f ollowill)..
199 omcE >
.......g,....,.. g... 210'
' ' ' ' ~ ~ ~
o cause of New Madrid Quake (us ic).....
206
$URhAME>
DATE >
..I.
Form AEC-3 ts (Rev. 9-53s AECM 0240
- o H e-a s.65 - t sis-n?a i
2-p !
=a wc 219;?m.
'5 : k
Statement by Member of the Public Cifallese)..........
5 Future Schedule........................
227 4
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7 I. -
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OFFICE >....
$URNAME>
DATE >
Fomw AEC-Sas (Res. 9-53) AECM 0240
+48-le-Hess-a 448-e7s
____._._._._._.______________________________;