ML17195A749
| ML17195A749 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 04/05/1985 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Reed C COMMONWEALTH EDISON CO. |
| References | |
| CAL-85-04, CAL-85-4, NUDOCS 8504110325 | |
| Download: ML17195A749 (3) | |
Text
.
e CONFIRMATORY ACTION LETTER e.
Docket No. 50-237 Commonwealth Edison Company_
ATTN: *Mr. Cordell Reed Vice President Post Office Box 767 Chicago, IL 60690 Gentlemen:
APR 5 1985 CAL 85-04 This refers to the discussion between Mr. R. Rybak of your staff and Mr. J. F. Streeter of my staff on April 5, 1985, regarding monitoring and surveillance actions you will take as a result of the damage sustained by several main steam piping mechanical snubbers on Dresden Unit 2 during the last operating cycle.
With regard to the matters.discussed,* we understand you will take the following actions:
- 1.
Monitoring system operability:
- a.
Periodic verification of the operability of the recently installed main steam (MS) \\transient monitoring system will be conducted in accordance with Special Procedure 85-4-76 or Technical Procedure DTS020-3.
- b.
An assessment will be made of the impact on the operability of the monit.oring system and a verbal report will be made to Region III within 2 working days should any component of the monitoring system become unable to perform its intended function.
A followup written report will be submitted to Region III within 30 calendar days.
- c.
Commence a,plant shutdown within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> if either 4 or more strain gages (SGs) are inoperable or the monitoring system is otherwise determined to be inoperable.
The monitoring system will be restored to an operable condition prior to resuming power operation.
2..
Response to SG signals:
- a.
A verbal report will be made to Region III within 2 working days followed by a written report within 30 calendar days if the following SG signal indications are obtained:
(1).At or above 15 Kips but less than 20 Kips.
(2)
At or above 20 Kips.
(The written report will include a safety evaluation.)
e-CONFIRMATORY ACTION LETTER e CAL 85-04 Commonwealth Edison Company 2
APR 5 1985
- b.
An*evaluation will be conducted to determine the cause of the signal when any of the.SG.signals reach or exceed the following force. levels:
MS Line B MS Line C MS Line D Snubber Force Snubber Force Snubber Force No.
Level No.
Level No.
Level 46 25 Kips 44 20 Kips 52 35 Kips 50 25 Kips 53 25 Kips 51 30 Kips
- c.
A plant shutdown will be commenced within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for main steam piping inspection when the force levels in Item 2.b are exceeded
- unless the evaluation determined the signal cause to be (1) instrument malfunction, (2) power supply transient, (3) electronic noise, or (4) personnel error.
- 3.
Within 6 months after returning Unit 2 to power operation:
- a.
The MS piping transient monitoring program will be enhanced by
. defining the linear variable displacement transducer (LVDT)
- b.
set levels which will be in addition to the SG set levels described in Item 2.b.
The present instrumentation will be modified such that all 12 recorder channels will print out when any of the SGs or LVDTs sense signals at set levels.
(The interruption of the MS piping transient monitoring program due to modification, hookup, calibration, and testing will not exceed a total cumulative time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> without notifying Region III.)
- c.
Prior to initiation of Items 3.a. and 3.b. these actions will be discussed with Region III.
- 4.
During the next Unit 2 refueling outage:
- a.
The following safety-related mechanical and hydraulic snubbers will be functionally tested:
Snubber No.
44' 51,. 53 1527 Type & Size PSA-35 PSA-10 Location Main Steam Lines C and D LPCI
CONFIRMATORY ACTION LETTER CAL 85-04 I'
-* Commonwealth Edison Company 3
APR 5 1985 17.
PSA-35 Recirc. Loop B Ring Header 36 PSA-35 Recirc. Loop B Pump Discharge 7, 8, 9 PSA-35 Recirc. Loop B Pump Body 1514 PSA-100 Torus Ring Header 1510' 1506 AD-55 Torus Ring Header 1301, 1302, 1303 Grinnell Hydraulic Isolation Condenser 2f".Bore Cylinder 2302 PSA-f HPCI Vent 1526 PSA-f LPCI Vent 1604, 1605 PSA-t Torus Drain 1530 PSA-i LPCI Vent
- b.
Any snubber or structure damage identified during inservice inspections and any snubber functional test failures will be verbally reported to Region III within 2 working days followed by a written report within 30 calendar days.
Please inform us immediately if your understanding of these actions are different from that stated above.
cc:
D. L. Farrar, Director of Nuclear Licensing D. J. Scott> Station Superintendent DMB/Document Control Desk (RIDS)
Resident Inspector, RIII Phyllis Dunton, Attorney General's Office, Environmental Control Division R. Kiessel, IE F. Cherney, MEB, NRR James G. Keppler Regional Administrator RIII t:
RIII I
Yin/jk D~n 04/03/ 5 No~s RIII IL c~-~imos at;}~
s2i:':i~~*
~~ll/lB