ML20114E777
| ML20114E777 | |
| Person / Time | |
|---|---|
| Site: | 05000214 |
| Issue date: | 08/05/1964 |
| From: | Woodard M US ATOMIC ENERGY COMMISSION (AEC) |
| To: | US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML093631134 | List:
|
| References | |
| NUDOCS 9210120269 | |
| Download: ML20114E777 (7) | |
Text
4
\\
@ G. $4 UNITED STATES GOVERNMENT Memorandum To File.,
D AT E: AUG 5 1964
('1hru ) Roger S. Boy,
hief Research & Power Reactor Safety Branch
[
FROM M. Keith Woodard
~~
Research & Power
- #e ~
anc Division cf Reactor Licensing O'k'
^
stagcT: MEETING TO RESCLVE PRCBLEMS CN MALIBU IJ: SIGN The third meeting between the Staff and the City of Lca Angeles was held en July 30, 1964 to discuss the recommendations of the m,Z.3 letter and discrepancies of Amendment No. 5 pertaining to the Malibu plant.
Don Knuth presided with representatives of the City cf Los Angeles, Westinghouse and Stone & Webster present as fellevs:
E. Koffman COLA M. Frankel CCLA G. Luhnan COLA E. J. Povell Westinghouse T. Stern Westinghouse J. D. McAd oo Westinghouse S. N. Ehrenpreis Westinghouse
?. F. Engelhardt Westinghouse C. T. Chave Stone & Webster D. Gans, Jr.
Stone & Webster K. W. Sieving Stone & Webster M. J. Holley, Jr.
Stone & Webster R. M. Jacobs Stcne & Webster l
J. D. Goodrich Stone & Webster l
M. M. Mann REG.'
R. F. Fraley ACES Staff R. L. Doan DRL E. G. Case DRL J. F. Newell DEL D. F. Knuth DRL M. K. Woodard DRL R. R. Paccary IBS G. F. Ladlock OGC R. A. Williamson AEC Consultant Items of concern included tsunamis, containment stress criteria, seismic design of the containment, unborated water injection accident, hydrolcgy, cff-gas filters in the line be' ween the pumpback 'tousing and the stack, emergency power generator capacity, and a proposed movement of reactor building on the site.
A curmary of the discussion follows:
f ' v120269 920520 t
Files EUNAMIS E. Koffun stated that COLA vas unable to find a tsunami expert who would testify that a tsunami of 50 feet was incredible.
Most cf the experts are of the opinion that a verticle slip of the eft-shore.d slands is a credible mechanism for production of a 50 foot tsunami.
COLA, therefore, propores to design their plant so that a 50 foot tsuami vould not impair the function of the (1) emergency generators, (2) pumpback ccepressors, (3) after-heat removal systems, (h) containment integrity, and (5) devices necessary to keep-the reactor shutdown.
CONTAINMENT STRELSES The staff feels that the containment design stress criteria is not conservative. khen asked if there had been a precedent for such design criteria, Stone & Webster cited Connecticut Yankee as having a similar criteria. A check into the Connecticut Yc.nkee cpplication revealed that the containment was stated to have been cesigned to the ACI-318 code. Eevever, Stone & Webster quoted their verking stresses as being higher than those recommended in the code. 'Itey explained this discreparcy as being a problem of interpretation.
hey consider the ho paiC accident pressure to be an intermittent loading and vere, thers. fore, able to design with accident seresses (as allowed by the code) higher than those defined as working stresses.
Our opinion vas reiterated - that the containment should be designed to vittstand the maximum hypothetical accident without exceeding verking stresses.
S & W further argued that the codes were not written for steel lined, pressurized concrete structures and, therefore, do not apply to this case.
he complexity and size of this structure requires that the designer calculate the loads at many different locations. If this is donc properly, S & V believes they may take the credit necessary to design to higher loadings.
The code recommends a working stress of 20,000 poi and S & W reque-ts 27,000 psi considering the 40 psi pressure alone.
AltL " dh the present design for the earthquake and simultaneous 40 poi pressure is 32,000 psi, the staf f feels that if the design is based on vorking stresses for the hO psi accident pressure, the combf med earthquake - pressure stresses vill be within code recommendations.
Files.
l For a containment to remain leak-proof a high degree of i
reliability and, thus, conservatism must be evident in the design.
When asked about crack vidths and expansions with their design, S & W assured the staff that the integrity of the liners vould be maintained even with a loading as high as 32,000 poi.
The liners themselves vould experience a load of 22,000 pai.
S & W was asked if the stresses at the velds are the controlling factor or if it va; in the previously t
unstessed lining.
They ansvered by stating that different things controlled at different parts of the containment.
For instance, there is large bending at the base but the seal there is ductile.
The steel membrane is net " pasted" to the concrete and vill not necessarily be over-stressed by local cracks in the concrete.
When asked what yields vere expected, S & W stated that the concret remained in the elastic range under the proposed combined loadings of 32,000 pai.
The distortion vould be about 0.7 inch, half way up in the radial direction, with the ho pai - 27,000 psi design.
Professor Holley stated that a 25% factor is added to the codes because cf the uncertainties which exist.
If a complete analysis is done on the centainment the 25% vill nct be necessary and the pmsent design vill comply with code recommendations.
Dr. Doan believes that part cf this 25% is included because of statistical variations in the materials.
S & W claims that material inconsistencies vill be at a minimum because of their quality control during each heat in reinforcement-tar fabrication.
This containment is also different from a pressure vessel in that the tremendous weight reduces the elongation stress in the verticle direction.
S & V pressed the point that this vessel vill be tested at the accident pressure and the stresses and strains measured to prove the adequacy of design.
l l
In summing up, acknowledgement must be made of the fact that i
there is no design code for pressurized concrete structures, Mr. Case asked S & W to consider a limit of 22,000 psi at i
40 psi and a 0.25g earthquake. After a caucus, S & W propos9d j
the stresses appearing in the right hand eclumn below.
They vill be submitted in detail later.
l l
t 7
y m7+
7 y-e m
+r
Files
.k-The design stresses are compared in the folleving table:
Condition Conn. Yankee Malibu Revised Malibu Application Application-Preposed at this meeting less than less than Normal temp.
20,000 20p00 and pressure SAIT plus 20,000 20,000 including bees earthquakes and plates 0 38 3AME plus 27,000 26,700 40 psi 1
j SAME plus k0,000 32,000 i
Lo psi pluc earthquake
.:s a
l Earthquake Baro 26,700 onlyv/ober-l ing or tempera-ture effects, i
Operating 24,000 stresses plun l
40 psi bars &
Plates (Temp.
effects worth 2500 psi) 1 Everything 32,000 l
including bending &
i
- temp, I
a l
l l
t i
k i
e i
i Files 3
i j
SEISMIC DESIGN j
Again, S & W vas asked why they had not designed to code stresses as Dr. Honsner (their earthquake, structural consultant) had j
recc= mended.
They claimed to have a safety factor of 1.8 before rupture with the present design.
i S & W has taken only the horizontal accelerations into account
,j in their containment design.
This was no particular problem for our structural consultant, R. A. Williamson, when only the earthquake occurs.
But if the pressure was hi ". concurrently, S
the containment vould effectively float and any verticle earth-quake motion could do considerable damage. -
I S & W vas asked what vould be the effect of both a verticle and
)
horizontal simultaneous acceleration.
They thought this vould be very difficult to answer.
Dr. Doan related their lack cf j
ubility to calculate thece effects to the need for conservatism beyond questionable doubt.
y 5 & W restated that the desi6n for class 1 componente included both verticle and horizontal earthquake motions.
The containment is the only exception.
l UNB0 RATED WATER INJECTION 8
T. Stern said Westinghouse had designed the Safety injection system vith a series of interlocks and procedures which only a caboteur j
could violate sufficiently to cause an accident.
The ensuing j
description considered the accident during reloading, the main point of which was a breaker which is always removed from the i
feedvater pump motors.
Tbd Stern stated that they would never vatt to operate these pumps during refueling or when the head was eff.
The staff was not convinced that the accident was impossible and j
Westinghouse gave additional Onformation.
The maximum insertion i
rate is 0.35%/sec. At this rate it would take 43 seconds te go critical.
It takes 100 seconds to run out of water in the secondary.
Westin6 house vould not say that this accident was not vorse than the maximum hypothetical accident.
The staff has not been cenvinced that the system should remain as designed, t
Filec
-o-s HYISOLOGY Dr. Frankel made general statements to the effect that e gle te geolcgical survey can only be made after the land has ' u
{
purchased. A two year oceanographf c stucy must be marm wtm 1
l reactor cperatiot. is required by the State of Califond '
Concerning the landslides, COLA's consultants have studied the problem and belive that the "once in 50 year rainfall" could prcduce a flow of 3300 efs down the canyon.
If a landslide dammed this flev and then burst, it vould add only 400 cfc.
j The channel under the site is designed to carry 5000 efs. They did not knov the amount of water which would be held behind the dam.
They were told that we have a consultant who has indicated flows of 10,000 cfs.
Hovover, if the plant is designed for a 50 foot tsunami, it could tolerate almost any flood credible.
IODINE FILTERS BEFORE STACK In Amendment No. 5 Westinghouse took credit for 90% iodine removal in calculating the off-site doses from a leak in the pumpback system external to the double barrier. Using this removal the.
tolerable leakage was found to be 0.4% per day of the containment tuilding. However, Westinghouse does not, show any filters in the system between the pumpback compressor housing and the stack.
They Gon't expect the system to leak this much but stated that filters vill be included anyway.
A calculation and method of extrapolation to accident conditions indicating hev the allovable double barrier leak rate is obtained was submitted at this meeting.
Pay Maccary thought the criteria were sufficient but still is not convinced that the method 'of meanuring this leakage is accurate.
IMERGENi.',Y GENERATOR CAPACITY Amendment No. 5 stated that 830 H.P. motor-generator capacity would be available after an accident. This is sufficient to operate cnly 3 fans, and the staff feels that the capacity should be sir,ed to accoommodate one other of the engineered safeguards in case the fan system should fall or be ineffective.
__.__.m
4 Files Tecause CCLA has put so much faith in their 9 million dollar underground pcver lines, they do not want to incorporate a larger emergency Eenerator.
hey mentioned removing this proposed line and adding a much larger generator.
COLA eventually propcsed to add 200 H.P. in generating capacity enabling them to operate 3 fans and the centainment spray system at once. At 2 east 1030 H.P. is necessary for this load.
he questien of automatic turnover of the cooling equipment vs.
operator actuation van brought up, he staff would like to see automatic actuation cf the cooling equipment upcn accident detection. Again we made the statement that the heat must be removed as fact as possible, and the building depressurized, not held in equilibrium at some high pressure.
RELOCATION CF FIACTOR COLA casually proposed to move the reactor 350 feet West for reasons of (1) less excavation, (2) more exclusion dista::ce. nnd (3) increased economy.
They were advised by OGC that this chculd be done before the construction permit is i sued.
If it ic done aft' ward, there is a possibility of having another hearin6 cc:
E. G. Case R. Maccary D. F. Knuth E. R. Denton S
P. E. Norian M. K. Woodard
. _ _ _ _