ML20066J205
| ML20066J205 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 11/22/1982 |
| From: | Weiss E HARMON & WEISS, UNION OF CONCERNED SCIENTISTS |
| To: | NRC ATOMIC SAFETY & LICENSING APPEAL PANEL (ASLAP) |
| References | |
| NUDOCS 8211230469 | |
| Download: ML20066J205 (8) | |
Text
P "H5P (NITED STATES T NHRICA
- 02 WV 22 g a NLCLEAR REGUIATCRY CCM4ISSION k[,{kl[,fERwrq SJ! % 7g y BEFORE 'IEE ATOMIC SAFETY AND LICENSING APPEAL BOARD Sh In the tutter of
)
)
ME'IROPOLITAN EDISCN CCMPANY
)
Docket No. 50-289
)
(Restart)
(tree Mile Island Nuclear
)
Station, Unit No.1)
)
G UNION T CONCERNED SCIENTISTS' RESPONSE 'IO APPEAL BOARD MEMORANDUM AND ORDER OF NOVEPEER 5,1982 Introduct; ion _
e In its Vemorandun and Order of Novenber 5,
1982, the Appeal Board expressed its present view, agreeing with UCS, that the viability of feed and bleed has been called into question by the recent Semiscale tests.
Even without the evidence of these tests, the Appeal Board indicated that the record does not support a conclusion that feed and bleed is a viable means of removing s
decay heat for 'IMI-1.
Memorandun and Order, Novenber 5,1982, Sl. op a t 6.
We Appeal Board noted that, without feed and bleed as a backup, natural circulation with heat removal via emergency feedwater is the only means of decay heat removal.
Id.
We so-called " boiler-condenser" mode of natural circulation has also not been adequately demonstrated.
Id. a t 7.
All that remains is liquid natural circulation.
%e record shows tm critical problems with natural circulation.
Se first is related to the unreliability of emergency feedwater.
Feedwater must be available to provide a heat sink for natural circulation.
We second is N
8211230469 921122
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9 sa
. that, even if feedwater is available, natural circulation will be stopped by c
the formation of stean, bubbles for most snall break LOCAs.
%e Appeal Board suggested a possible alternative to reopening the record for recolution of these problems and sotght the parties' views.
As to the first problem, the Board suggested designating a dedicated operator to manually operate the energency feedwater ("EEW") flow control valves. As to the second, it suggested pre-restart installation of hot leg high point vents as a means for renoval of the steam bubbles.
It is LCS's view that the current state of the record is insufficient to support a conclusion that these proposed changes muld solve the problems recognized by the Appeal Board and that reopening is required.
_ Reliability of EFW With respect to the question of control of emergency feedwater flow independent of the integrated control system, the Board notes that " [ t] he presence of a sa fety-grade manual control capabilfry is unclear from the reco rd."
Memorandtrn and Order, Novanber 5, 1982, S1. op. at 9, n.19.
LCS believes that, on the basis of this record, the EEW manual control capability
^
is not safety grade.
%ere is only one flow control valve for each steam generator.
In the event of a break in one steam generator, which causes isolation of that steam generator, a single failure of the other flow control valve would cause total loss of feedwater.
See Licensee Exhibit 1 at 2.1-25.
%is is true whether control of EEW flow is manual or autcznatic. W e long-term upgrade of EEW to safety grade requires installing two flow control valves in parallel for each steam generator.
Wermiel and Curry, f f. Tr. 16,718 at 30 (E'igure 1, 'IMI 1 EEWS).
We are aware that the Licensee now proposes to change the design of the plant so that EEW to a broken steam generator would not be isolated.
H.
D.
4.+.
4
. Hukill to John F. Stolz, August 2,1982 (incorporated in Licensee's Response to Appeal Board order of July 14,1982 at 20). We effect of this proposed change has not been evaluated on the reord.
Moreover, the evidence shows, and the Licensing Board found, that the reliability of the emergency fecdwater system itself, even after it is fully upgraded to safety grade, is not sufficient to provide the needed assurance of highly reliable decay heat removal.
PID at Paragraph 1950 (Dec. 14, 1981).
Wis was based on calculations of EEW failure rates which considered the presence of a dedicated operator to manually control EEW flow.
Wenniel and 4
Curry, ff. Tr.16,718 at Attachment 2, fourth unntubered page.
Werefore, the Appeal Ibard's proposal to assign an individual to control EEW flow manually in the interim mtil EEW is safety grade would not result in making the delivery of EEW to the steam generators adequately reliable such that liquid natural circulation could be found an adequate means of removing decay heat (even asstning, arguendo, that the high point vents had successfully removed steam and/or noncondensible gases, thus making liquid natural circulation possible).
Hot Leg High Point Vents
%e Appeal Board also proposes to require the installation of the hot leg high point vents as a means of rmoving the steam bubbles that will be formed l
for most small break [DCAs and which will stop liquid natural circulation.
As l
the Board is aware, LCS believes that installation of these vents is necessary prior to restart.
We question here, however, is whether an order requiring installation of the vents without reopening of the record is sufficient to ensure a highly reliable means of decay heat removal.
We answer to this l
question i s "no".
%ere are too many critical unanswered questions on this i
record.
l'6 u
. First, as the Staff testified at the oral argument before the Appeal Board, it is not clear that high point vents would be effective in restoring natural circulation. / Calculations were apparently done at Los Alamos which predicted that once the candy cane at the top of the hot leg was voided, use of the vents would not restore circulation.
Oral argument, September 1,1982 at 290-292.
Certainly, as the Staff seemed to recognize, a testing program would be required to verify the effectiveness of the high point vents for the purpose stggested by the Appeal Board.
We record as it stands clearly does not support a conclusion that the vents would make natural circulation adequately y
reliable given the presence of steam voids.
Second, it appears likely that some of the same difficulties with feed and bleed demonstrated by the Semiscale tests S-SR-1 and S-SR-2 might also be encountered in attempting to " bleed" the steam acetnulated in the hot leg throtgh the vents.
Depending upon the size of the vents, system pressure, and 7
the adequacy of the instrtmentation available to the operator, the flow throtgh the vents could in fact be two-phase or liquid, thus raising the potential for a net loss of reactor coolant system inventory.
For exmple, there is new no I
method of measuring the water level in the candy cane.
tus, the operator would not know whether steam or water was being discharged.
In addition, an attempt to eliminate a steam bubble in the candy cane when the primary system cdnditions do not provide an adequate margin to saturation could be an exercise in futility.
Under these circtustances, opening of the vents to relieve steam
-*/ Note that the early version of Licensee Exhibit 1 at 2.1-31 (M.21) stated:
"Ibwer-operated vents will be provided for the reactor coolant system in order to ensure that natural circulation and adequate core cooling can be maintained following an accident." (emphasis added) tis language was changed in Mendment 23 by deleting " ensure tha t" and replacing it with
" enhance".
Ib promise is now made that the vents will " ensure" natural circulation.
E
) might only result in causing more water to flash to steam.
(opening the vents lowers the pressure; if there is inadequate margin to saturation, more wter would flash to steam.)
Finally, even if all of above questions could be resolved, there still renains a very significant question respecting the adequacy of the operator training and emergency procedures to detect the need for use of the vents and to guide their stbsequent operation.
It should bo apparent frw the foregoing that this is far from a simple matter.
In fact, Item II.B.1 of NUREG-0737 required the development of procedures ard supporting analysis for operator use Q
of the vents, including. assessment of the information available to the operator for initiating or terminating vent usage.
Were is no evidence on the record to indicate that such procedures and analysis have been developed for 'IMI-1.
01 the contrary, with respect to the evidence or. the record, it is clear that the emergency procedures do not address use of 7.he high point vents.
Conclusion In sum, it is UCS's strorg view that restart cannot be authorized on the basis of the current record, even if the Appeal Board's suggested changes are 5
adopted.
'Ihere is, quite simply, insufficient evidence in the record to support a conclusion that use of the hot leg high point vents can be relied upon to restore liquid natural circulation.
In addition, the record shows that the use of a dedicated operator to control EFW flow will not make EFW adequately reliable.
Were are many potential ways in which an adequately reliable means of decay heat removal might be provided at 'IMI-1.
As suggested by the Semiscale test reports, plant specific analyses and tests could conceivably support the viability of feed and bleed.
Use of the reliability analyses perfonned by the Staff for the EFW system could pinpoint areas where further modifications to P
u
. that system muld improve its reliability, thus potentially eliminating the need for a back-up means of decay heat removal such as feed and bleed.
Other techniques, such as auxiliary spray from the makeup system directly into the high point of the hot legs, could directly condense the steam bubbles thereby avoiding the problems associated with use of the high point vents to " bleed" the steam out of the system.
01e should also consider methcds to enhance the reliability of the reactor coolant pumps so that they could be used to force circulation, cordensing the steam bubbles.
'Ihe record must be reopened in order to determine sat steps are required h
to assure adequate decay heat renoval for 'IMI-1.
Respectfully submitted, 1
/
(df lAV Ellyn R. Weiss
/
Counsel for UCS Harmon & Weiss 1725 I Street, N. W.
Suite 506 h
Washington, D.C. 20006 (202) 833-9073 Ihted: November 22, 1982 s
wy UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION In the Matter of
)
)
METROPOLITAN EDISON COMPANY
)
Docket No. 50-289
)
(Restart)
(Three Mile Island Nuclear
)
Station, Unit No. 1)
)
CERTIFICATE OF SERVICE I hereby certify that copies of " UNION OF CONCERNED SCIENTISTS' R ES PONS E TO APPEAL BOARD MEMORANDUM AMD ORDER OF NOVEMBER 5,
1982" have been served on the following persons by deposit in the United States mail, first class po s tag e prepaid, this 22nd day of November de 1982.
- Nunzio Palladino, Chairman Dr. Walter H.
Jordan U.
S.
Nuclear Regulatory Atomic Safety and Licensing Commission Board Panel Washington, D.C.
20555 881 West Outer Drive Oak Ridge, Tennessee 37830
- Victor Gilinsky, Commissioner U.
S.
Nuclear Regulatory Dr. Linda W.
Li t tl e Commission Atomic Safety and Licensing Washington, D.C.
20555 Board Panel 5000 Hermitage Drive
- John Ahearne, Commissioner Raleigh, North Carolina 27612 U.
S.
Nuclear Regul,atory Commission Professor Gary L.
Milhollin
'8 Washington, D.C.
20555 4 412 Greenwich Pa rkway Washington, D.C.
20007
- Thomas Roberts, Commissioner U.
S.
Nuclear Regulatory
- Judge Gary J.
Ed l es, Chairman Commission Atomic Safety and Licensing Washington, D.C.
20555 Appeal Board U.
S.
Nuclear Regulatory
- James Asselstine, Commission Commissioner Washington, D.C.
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S.
Nuclear Regulatory Commission
- Judge John H.
Buck Wa sh i ng to n,
D.C.
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- Ivan W.
Smith, Chairman U.
S.
Nuclear Regulatory Atomic Safety and Licensing Commission Bo a rd Panel Washington D.C.
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S.
Nuclear Regulatory Commission Wa sh i ng to n,
D.C.
20555 24 N
4 F Judge Christine N.
Kohl
- Mr. Steven C.
Sholly Atomic Safety and Licensing Union of Concerned Sciertists Appeal Board Panel 1346 Connecticut Ave., NW U.
S.
Nuclear Regulatory Washington, DC 20036 Commission Washington, D.C.
20555
- Counsel for NRC Sta f f Office of Executive Legal Judge Reginald L.
Gotchy Director Atomic Safety and Licensing U.
S.
Nuclear Regulatory Appeal Board Panel Commission U.
S.
Nuclear Regulatory Washington, D.C.
20555 Commission Washington D.C.
20555
- George F.
Trowbridge, Jsq.
Shaw, Pittman, Po t ts &
Mrs. Marjorie Aamodt Trowbridge R.D.
85 1800 M Street, N.W.
Coatesville, PA 19320 Washington, D.C.
20036 Robert Adler, Esq.
- Docketing and Service Section 4
Assistant Attorney General Office of the Secretary 505 Executive House U.
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Nuclear Regulatory P. O.
Box 2357 Commission Harrisburg, Pennsylvania 17120 Washington, D.C.
20555 Louise Brad ford Three Mile Island Alert 325 Peffer Street Harrisburg, Pennsylvania 17102
,g' 42/
4/
Jordan D.
Cunningham, Esq.
Hand Delivered Fox, Fa r r & Cunningham 2320 North Second Street Harrisburg, Pennsylvani a 17110 Dr. Judith H.
Johnsrud c'
Dr. Chauncey Kepford Environmental Coalition on Nuclear Power 433 Orlando Avenue State College, PA 16801
- William S.
Jordan, III Harmon & Weiss 1725 Eye St.,
N.W.,
Suite 506 Washington, D.C.
20006 John A.
Levin, Esq.
Assistant Counsel Pennsylvania Public Utility Commission P. O.
Box 3265 Harrisburg, Pennsylvania 17120 Ms. Gail B.
Phelps 245 West Philadelphia Street York, Pennsylvania 17404 t