ML19312C741
| ML19312C741 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 06/20/1967 |
| From: | Grimes B US ATOMIC ENERGY COMMISSION (AEC) |
| To: | Boyd R US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 7912190950 | |
| Download: ML19312C741 (4) | |
Text
-__ -_
JUN 2 0 loc' I
Roger S. Boyd, AD/RP, DRL TdRU: Charles G. Long, Chief, RPB #3, DRL vi 3
B. Grimes, Reactor Project Branch No. 3
@% o 6 o
Cr Division of Reactor Licensing 04Q. \\t*
31, 1967,Gbg ON OCONEE NUCLEAR STATION -
ACRS SUBCOMMITTEE MEETrJG MAY DOCKET NOS. 50-269, 50-270, & 50-287 4
On May 1967, an ACRS Subcommittee meeting on the Duke Power Company's Oconee-fuelear Station was held in the H Street Offices. A meeting agenda and a list of persons representing the applicant are attached. A functional organizational chart for the B&W Company is also attached. Attendance by DRL and the ACRS was as follows:
DRL ACRS R. S. Boyd C. Zabel C. G. Long S. Hanauer B. Grimes J. Hendrie i
D. Sullivan R. Wilcox, staff R. Waterfield Salient points of discussion at the meeting follow:
1.
Several items discussed at the May 2, 1967, site visit were dis-cussed. The applicant presented a summary of the affluent release study presented in Amendment 4 and indicated that both high and low level monitoring equipment would be provided at the operating license stage. They were requested to compare their analysis with the Monticello analysis (Amendment 4, Question 3.3).
It was brought out that about half of the water storage at Clemson was fire reserve leaving about 2/3 day supply of water for normal uses.
2.
Reactor Design The following questions were posed to the applicant on the con-trol rod drive system:
a) What are the resistive forces on scram? B&W had concidered inertial forces but was not sure what the friction forces were.
b) What forces are exerted on the drive if a w l completely fails? This will depend on the restrictions within the vessel and will be looked at as well as the failre of the vent on top of the housing.
OmCE >
I
$URNAME>
DATE >
I Form AEC 318 (Rev. 9-52) u m 'imiPmTM N i M 21 m
i i
JUN 2 01967 Roger S. Boyd 9 c) What are the forces on the control spiders during blowdown?
I d) The Subcoinnittee commented that the ability to drive rods down after a scram signal is desirable and should be ser-iously considered by the applicant.
3.
Coolant System The applicant stated that primary side blowdown tests as cell as secondary side blowdowns would be performed (at the request of the staff) on the steam generator but that it will be a year or two before they can be fit into the testing schedule.
j l
Steam could be provided to the feedwater pumps by the house boiler if both steam generators blev down after a steam line break accident (due to multiple stop valve failures). The steam would be available well within the 2-hour period in which the core would uncover. Feedvater could also be supplied from the other units after their installation.
B&W indicated that they would not have an independent check of the vessel stress r.nclysis but a rough check would be perforned by the Boiler Di'r'.sion of B&W.
The Subcommittee asked that the Occnes steam enerator tubes be compared with Shippingport.
4.
Engineered Safeguards The applicant stated that the criterion for allowing single pipes in the engineered safeguards systems is that they be missile-protected.
After some discussion the applicant proposed that the low pres-sure injection pumps would be protected from flooding by provid-ing morethan one compartment for the pumps and providing drain-age from any overflow. This would take care of a major line break at the pumps and still allow some core injection capability.
5.
contairement It was stated that 100% of the containment surface would not be inspected while the building was at pressure but that all high stress areas and additional random areas would be inspected.
i OFFICE >
$URNAME >
oaTE > l.........
j Fom AEC.318 We.M u.s.comwat mnimo cnu. im-o-m-ea i
l
3-Roger S. Boyd JUN 2 01967 It was indicated that the personnel access hatch doors were sealed by a single gasket rather than two gaskets as was understood by the staff. The vent line to the penetration room is now run from the cylinder between the doors, The applicant indicated to me informally that this may be changed to a double seal on the outer door with the vent 11ac run from 1
between the seals on the outer door.
An agenda for the full Committee meeting on June 8 was discussed and is generally the same as that followed for the Subcommittee meeting except that the applicant was asked to be especially prepared to discuss the calculation of the thermal transient after a loss-of-coolant accident.
j Other items which were brought up in the staff session with the Sub-coamaittee were asifpliows:
a) What is the effect of a rod drop into the core on the operating thermal characteristics?
(In case it was not i
detected would the rest of the core be over-driven?)
b) The Subcommittee expressed interest in the control rod and feedwater control systems.
c) What is the effect of a fueling error in the zoned coref other items which the staff has interest in resolving are as follows:
a) Has siphoning after a coolant line break been considered?
b) Based on informal discussions I understand that the reason for an increase in the structures quoted as heat sinks is a result of further design refinement and is not associated with the reduction in containment volure.
c) Ns statement was ircluded to clarify the role of the ground motion spectra yresented. Based on a ccnference call with J. Fischer of Dases and Moore and Drs. Newmark and Hall, we understood that reference to ground motion spectra were to be deleted and only the response spectra would be used in the design.
d)
In the revised answer to Question 4.1 in Amendment 4, refer-ence is made to the failure of one unit taking out the 13.8 Ky cable. Based on conversations with W. Lee and C. Wylie of Duke Power, this is only a temporary desnergization since the cable is switched to the second unit in case the first fails to start.
l
'e OmCE >
SURNAME >
DATE >
Fbrm AEC.318 (Rev.9-53)
U.S. sovenntwT Pentme cFrxx : 1966 -o-214-629
{
~_ _
~
4-3 <j Q g Roger S. Boyd e) A:nendment 4 indicates that reinforcing bar in the contain-ment may be tack-welded.
F. Schauer has expressed concern that unless rigid quality controls are imposed, the weld area may become embrittled and cause failure of the bar at that point.
Attachments:
1.
Agenda 2.
Attendance list 3.
B&*J ora,anizational chart O
Distribution:
Suppl. (3),
y,,7 DRL Readirig RPB #3 Reading S. Levine D. J. Skovholt D. R. Muller R. Tedesco C. G. Long R. Ireland B. Grimes
..P,.B.",'#.3 s.DR..L......
..R..P. B...#.3. -DRL R
OmCE >
A,
.i
!:.L L Grimes /1tj cLong SURNAME >
DATE > l. 6-13-67
\\
6-4-67
..A.
Form AEC.318 (Rev. 943) us. c.ovunwet mmnme crmr am--o-218-63