ML19321B129
| ML19321B129 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 07/11/1980 |
| From: | Peoples D COMMONWEALTH EDISON CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| IEB-80-17, NUDOCS 8007280074 | |
| Download: ML19321B129 (5) | |
Text
[T Commonwealth Edison a
/
' * - oni First Nationti Ptrza. Chicsgo, tilinois k
O h Address Riply to: Post Offica Box 767
\\D- - 1 Chicago, Illinois 60690 July 11, 1980
'JUL 15 t980 Mr. James G. Keppler, Director Directorate of Inspection and Enforcement - Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road 4
Glen Ellyn, IL 60137
Subject:
Quad Cities Station Units 1 and 2
-Additional Response to IE Bulletin 80-17 NRC Docket Nos. 50-254/265 Reference (a):
J. G. Keppler letter to C. Reed dated July 3, 1980 Oear Mr. Keppler:
This letter provides Commonwealth Edison's additional response for Quad Cities Units 1 and 2 to certain items in IE Bulletin 80-17, transmitted by Reference (a).
The attachment to this letter contains the response to Items 2 and 3 of the bulletin for Quad Cities Unit 1 and Items 4, 5, 6a and 6b for both Quad Cities Units 1 and 2.
Responses to remaining items of the bulletin will ce provided in accordance with the schedule identified therein.
Please address any questions concerning this matter to this office.
Very truly yours, h
LV &
D.L. Peopl s Direr. tor of Nuclear Licer sing cc:
Director, Division of Reactor Operations Inspection SUBSCRIBED and SWORN before(vne phis
//7/, day of y alt, 1980 G
Notsry'Public 5164A
,80072.80 07
o Attachment Quad-Cities Station Response NRC IE Bulletin 80-17 Item 2 Temporary procedure number 1358 was written to gather data (Unit 1 as required in Item 2 for Unit 1.
On July 5, 1980, a only) manual scram was performed at 100 MW thermal to gather cata.
On July 6, 1980, an automatic scram from IRM upscale was performed by down-ranging the IRMs at 25 MW thermal.
a.
Twenty-two control rods scram insertion times were obtained utilizing a multi-pen recorder.
This was the maximum number of rods that could be timed in this manner.
From this information, an all-rort insert time can be estimated from the slowest of these rods.
There was no feasible way to determine the actual all-rod insert time.
TIMES:
3.64 sec Manual Scram 3.16 sec Automatic Scram The faster time for the automatic scram could have resulted from the fact that the additional insert and withdrawal aided to free or loosen the rod motion thereby decreasing insertion time.
The identical rod was slowest "in" during both scrams.
The times listed above are compara~le to those found during hot scram o
timing surveillance.
Computer scans of control rod notch positions also verified all rods were inserted past 06.
A visual check was also done to verify this at the time of testing.
b.
Voltage was measured across the scram solenoids while the scram signal was present.
The voltages for all four groups of both channels were.ound to be zero.
" Iso, the group lights on the 901-> panel went out which is a positive indication of loss of voltage.
c.
An operator was stationed at the backup scram solenoids during both scrams.
The valves operated correctly and air was vented as designed.
d,h.
The filling and draining of the instrument volume was monitored by attaching a multi-pen recorder to monitor the magnetrol level switch contact actuation.
The following chronology for the manual and automatic scrams is provided to indicate the events as they occurred:
MANUAL AUTOMATIC t=0 Reactor Scram t=0 27.8 sec SDV not drained alarm 31 sec 38 :2 sec SDV high level Rod Block 39.1 sec 29.8 sec SDV high level Scram 30.5 sec 96 sec Reset scram in Control Room
- 1 min 5 sec 155 sec SDV drain opened 2 min 18 sec 159.8 sec SDV not drained alarm reset 2 min 25 sec 184.4 sec SDV high level Rod Block cleared 2 min 51 sec 195.8 sec SDV high level scram cleared 3 min 4 sec 297.7 sec SDV not drained alarm came up not recorded not recorded 304 sec SDV high level scram came up 16 min 30 see SDV not drained alarm reset not recorded 17 min 50 sec SDV high level scram cleared not recorded All alarms cleared
- 17 min 5 sec
- Values determined by stopwatch.
The above data appear inconsistent and were unexpected.
Recognizing the need for further investigations, another test was performed.
Water was admitted slowly into the instrument volume utilizing a test connection (used for calibration of the level instruments).
The following data were acquired:
FILL TIMES -
3 gal 2:05 min 25 gal 5:20 min 50 gal 10:25 min DRAIN TIMES -
50 gal 20 sec 25 gal 46.9 sec i
j 3 gal 34.7 sec As shown in all three cases, inconsistent and questionable results were gathered upon draining the J
volume.
A possible explanation of the instrument behavior can be associated with the drain line piping configuration.
The upper or vent instrument legs are connected to the two-inch pipe which drains the SDV to the instrument volume.
The act of draining the volume apparently results in the erratic performance of the instruments.
Inte-ruption of the draining allowing level to equalize, or the slow filling of the volume yielded results as would be predicted.
This phenomena has been referred to General Electric Company and to the CECO Station Nealear Engineering Department.
This sequence of events is not an adverse safety concern, because the si'w filling of the volume would be the more realistic situation, since the SDV drain and vent valves are normally open during reactor operation and the system has been adequately demonstrated to be mechanically installed and electrically connected as designed.
~ e,f.
Stroke times of the vent and drain valves were obtained prior to the test scrams.
These times werd as follows:
Opening Closing Scram Closing Time 1-302-22 Less than 1 sec 1.5 sec 5.5 sec 1-302-21A Less than 1 sec 8
sec 11.5 sec 1-302-21B Less than 1 sec 1
sec 4.5 sec g.
A water sample was taken after each of the scrams and analyzed for total suspended solids Manual Scram 4 ppm Automatic Scram 3 ppm i
step was verified by the technique as outlined in our response to Item 1.
(Ref.
R. F. Janecek letter to J. G. Keppler dated July 10, 1980).
The instrument volume did not cool sufficiently between the two scrams to enable use of this procedure.
During the Unit One startup the test was satisfactorily performed, which also began the testing required by Item 5.
J.
A scram was not required to determine the scram reset delay times.
The procedure to acquire the needed data was to manually close the individual scram relays while monitoring the voltage across the reset contacts.
The period of time in which voltage was zero represents the reset times required.
Channel A Groups 1 & 4 ----- 15 sec Channel A Groups 2 & 3 ----- 15 see Channel B Groups 1 & 4 ----- 19 sec Channel B Groups 2 & 3 ----- 20 sec k.
All data acquired have been reviewed and are acceptable.
The results are comparable to data obtained from scram timing surveillance.
Item 3 At the conclusion of each of the two scrams, the vent (Unit 1 valves were observed to open.
This verification was per-only) formed after the scram was cleared, the water sample taken, ano the instrument volume draining was done.
The l
scram discharge volumes were verified to be drained during the Unit 1 startup.
A procedure change is to be made to require that after each reactor scram,_a verification is made that no significant amount of water is in the SDV.
)
l
Item 4 A review of the Quad Cities Station scram procedure, QGP 2-3, has been conducted by the Station a'd General Electric Company.
Based on G.E. guidelines and discussions covering existing and proposed procedural steps, a new procedure (QGA-19) has been written to cover those actions necessary when control rods fall to fully insert during a scram.
Steps have been added to QGP 2-3 to provide an entry point into QGA-19.
The Browns Ferry occurrence and the new QCA-19 procedure and revised QGP 2-3 procedure are being reviewed by licensed operators.
Training of the Shift Engineers, Shift Foremen, Control Room Operators, and licensed Equipment Operators should be completed by July 13, 1980.
Full training of other licensed Station personnel should be complete by August 2, 1980.
Item 5 Temporary procedure 1355 is being performed daily on both units.
Results to date have been acceptable.
The interval will be extended to weekly pending continued successful results.
Consideration is being given to making this procedure permanent.
Item 6a Prompt notification (within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) by Red Phone, with written follow-up (14 day LER) will be provided for HPCI, RCIC, SBLC, and RHRS-Suppression Pool Cooling being less than fully operable (when required to be operable).
Item 6b Existing procedures spec;fy those actions necessary to initiate suppression pool cooling for high pool temperatures.
5164A
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