ML17199F588
| ML17199F588 | |
| Person / Time | |
|---|---|
| Site: | Dresden, Quad Cities, 05000000 |
| Issue date: | 12/26/1985 |
| From: | Zwolinski J Office of Nuclear Reactor Regulation |
| To: | Farrar D COMMONWEALTH EDISON CO. |
| References | |
| GL-83-08, GL-83-8, NUDOCS 8601060548 | |
| Download: ML17199F588 (5) | |
Text
- , -..
Docket Nos. 50-237/249/254/265 Mr. Dennis L. Farrar Director of Nuclear Licensing Commonwealth Edison Company Post Office Box 767 Chicago, Illinois 60690
Dear Mr. Farrar:
December 26, 1985
SUBJECT:
MODIFICATION OF VACUUM BREAKERS ON MARK I CONTAINMENTS (GENERIC LETTER 83-08)
Re:
Dresden Nuclear Power Station, Unit Nos. 2 and 3 Quad Cities Nuclear Power Station, Unit Nos. 1 and 2 By letter dated July 12, 1983 you responded to Generic Letter 83--08. dated February 2, 1983.
We are continuing the review and find that we need the information requested in the enclosure to this letter in order to complete our review regarding the vacuum breakers.
Please respond to this request on a schedule to be negotiated with your project managers.
You should be aware that I would like to see this effort resolved in a timely manner.
This request for information was approved by the Office of Management and Budget under clearance No. 3150-0011.
Comments on burden and duplication may be directed to the Office of Mana~ement and Budget, Reports Management~
Room 3208, New Executive Office Building, Washington, D. C.
20503.
Enclosure:
As stated cc w/enclosure:
See next page DBL:PD#l~
CJamersor(J 18./ J3/85
- R~
DBL:PD#l RGilbert:jg
)1/."J.3 /85
. 8601060548 851226 l ~~R
- A DOCK 05~~~~~
~ _ L...
Sincerely, ORIGINAL SIGNED BY John A.
Zwo~inski, Director BWR Project~Directorate #1 Division of *BWR Licensing DISTRIBUTION Docket NRC PDR Loca 1 PDR.
PD#l ROG RBernero OELD RBevan GHolahan EJordan BGrimes JPartlow JZwol inski CJamerson ACRS ( 10)
RGi lbert
- wton9}..
DBL: PD#}o.J RBevan ~
/'Y/?-}/85 DBL:PD#~
JZwolinski j-Z,. h q-/85
. ~-
. Mr. Dennis L. Farrar Conmonwealth Edison-Company cc:
Mr. B. c.- O'Brien President Iowa-Illinois Gas and
- *.. Electric Company
. 206 East Second Avenue Davenport, Iowa 52801 Robert *G. Fitzgibbons, Jr.
Isham, Lincoln.& Beale Three First National Plaza Suite 5200 Chi ca go, 11 li noi s 60602 Mr. Nick Kalivianakis
- Plarit Stiperintendent Qtiad Cities Nuclear Power Station
- 22710 - 206th Avenue - North
- Cordova, Illinois. 61242 Resident Inspector U. S. Nuclear Regulatory Commission 22712 206th Avenue North Cordova, Illinois 61242
- Chairman Rock Island County Board of Supervisors
. Rock Island County Court House.
Rock Island, Illinois 61201 Mr. Gary N. Wright Nuc1ear Facility Safety*
Illinois Department of Nuclear Safety 1035 Outer Park Drive, 5th Floor Springfield, Illinois 62704
- Regional Administrator, Region III.
U. S. Nuclear Regulatory Conm~ssion 799 Roosevelt Road Glen Ellyn, Illinoi~ 60137 Mr *. Doug Scott Plant Superintendent Dresden Nuclear Power Station Rural Route #1.
Morris, Illinois 60450-
./
Dresden Nuclear Power Station Units 1, 2 and 3 and Quad Cities Nuclear Power Station, Units 1 and 2 U.S. Nuclear RegulatoryCorranission Resident Inspectors Qffice Dresden Station Rura 1 Route #1
- Morris, Illinois 60450
- Chairman Board of Supervisors of Grundy
-. *County Grundy County Courthouse Morris, Illinois 60450
- 4**"
REQUEST FOR ADDITIONAL INFORMATION RELATED TO THE MODIFICATION OF VACUUM BREAKERS ON MARK I CONTAINMENT COMMONWEALTH EDISON COMPANY DRESDEN NUCLEAR POWER STATION, UNIT NOS. 2 AND 3 QUAD CITIES NUCLEAR POWER STATION, UNIT NOS. 1 AND 2 DOCKET NOS. 50-237/249/254/265 The resl.i-1 ts <?f the s:taff review of the Dresden 2 and 3 and Quad Ci ties 1 and 2 (D/QC) torus-to-drywell vacuum breaker modification identified several areas where further infonnation is needed before' the staff can complete its review.
These.:areas surranarized below were delineated in the staff's generic evaluation
. of the methodology proposed to predict vacuum breaker valves opening and closing
- impact velocities, letter from D. Vassallo to H. Pfefferlen, dated December 24, 1984 (copy attached).
- 1.
- Is the chugging ~ource rate used in the D/QC evaluation the same as the on~ developed in CDI Report (#84-3)? If.not the same, ~rovide the *
. chugging source rate.with the supporting justif.ication.
- 2.
Did the D/QC calculation apply the 1.07 load factor to account for the uncertainty in calculating the underpressure (Section IV' of the staff's generic evaluation)?
- 3.
Have the D/QC calculations used the dr,YWell model which results in the most conservative prediction (Section V of the generic evaluation)?
I
**----~-----~*****-*-
- -*~*--* *- -*------*-*---------**.. --.-
~.
~U-~R R~~~~~~~T~~OMMISSION..* *.. *
.. WASHINGTON, D. C. 20555 Mr. H. c. Pfefferlen, Manager BWR Licensing Programs General Electric Company
. *
- 175 Curtner Avenue, MC 682
.*San Jose, California 95125
Dear Mr. Pfefferlen:
December 24, 1984.
SUBJECT:
.*£VALUATION OF f40DEL FOR PREDICTING DRYWELL.
TO WETWELL VACUUM BREAKER VALVE DYNAMICS.
- ATIACHMENT *...
- _The* staff issued Generic letter 1!3-08 dated February 2, 19B3, 1:0 all
_.,,applicants and licensees of plants with Mark J contafoments requesting
- submittal of information related to a potential failure mode of the
. drywell-to-torus vacuum breakers during the ch~gging and condensation oscillatf on phases of a Loss-of-Coolant Accident (LOCA). - As stated i*n *the
-.... * **..,eneric letter, this 1ssuP was discovered at the time the. generic phase.of C
~
the Mark I Containment Long-Term Program was near completion, however, the.
. :- -1 *
..
- fi'.ark I Owners Group coirm1tted to resolve this issue although not
~necessarily as 'l)art of the NUREG-0661 long Tenn Program. **
..... ~
-. To nsolve the generic aspects of this issue the following reports were * *.
prepared by Continuum Dynamics Inc. (COi) for the General Electric Company
.* and the Mark I Owners Group:
-. COi TECH NOTE 82-31, *Mark I Vacuum Breaker Improved Dynamic Model -
. * -.. ~.
_ *. * -.. Model Development and Validation* transmitted by your letter tlated * * *: *
- _, *
- October 28
- 1982
='?
....... :t. :";-*:
- CDI Report No. 84-3, **Mark I Wetwell to Orywell Vacuum Breaker Load.*
.. *ftethodology* transmitted by your letter dated March 2, 1984
- These reports describe the models to~ used*to compute the vacuum breaker valve response to chugging and condensation events in Mark I plants.
Based on our review of these reports and the additional information provided in your letters dated September 26, 1984 and November 6, 1984, we have concluded that the valve dynamic modP.1 conservatively predicts the.
- opening end closing velocities for the valve and, therefore, is acceptable for use.in the analyses and/or qualification of Mark I wetwe11-to-drywe11 ANO 85fH~48S92
.. *.*: ~... _*_..
~- '.
Mr. H....
-vacuum breaker valves subject to the restr1ct1o~s set forth in.SPcti~n V of the enclosed Safety Evaluation (SE).
-~,..
Sincerely, nic s*. Vassallo, Chief_.
Operating Reactors Branch 12 Division of.L 1censing
~
',~\\
_J
~----*
- .*~ -. *.--*:*
Enclosure:
As stated
.*. ~.
.. _-:*:'.. i*.. :_ *..
- ~:*_.. :... *.. *; _....
.... ~*-.. '....
- ~ :.. '*
-.;.-..~*--:_*.-_-:..
,_