ML20086J852
| ML20086J852 | |
| Person / Time | |
|---|---|
| Site: | Byron  |
| Issue date: | 11/21/1991 |
| From: | Kovach T COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9112120102 | |
| Download: ML20086J852 (3) | |
Text
---
Commonwealth Edison 100 opus Place
- l D wners Grove, minds 60515 November 21,1991 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC' 20555
Subject:
- Byron Nuclear Power Station Units 1 and 2 Respo.nse to Notice of Violation Inspection Report Nos. 50-454/91022; 50-455/91022 NRC Docket Numbers 50-454 and 50-455
Reference:
H. Miller letter to Cordell Reed dated October 22nd transmitting NRC Inspection Report -
50-454/91022;50-455/91022 Enclosed is Commonwealth Edison Company's (CECO) response to the Notice of Violation (NOV) which was transmitted with the reference letter and Inspection Report. The NOV cited are Severity Level IV violation. The violation concerned the tailure to collect Type A leakage rate test data within the required timeframe. CECO's response is provided in the following attachment.
In addition, page 15 of the inspection report states, in part. "During the 1991 Unit 1 Type A test, the inner door shaft seal on the emergency airlocks... " should read "During the 1991 Unit 1 Type A test, the inner door seals on the personnel airlocks.. " Please note this correction.
if your staff has any questions or comments concerning this letter, please refer them to Denise Saccomando, Compliance Engineer at (708) 515-7285.
Very truly yours, y
n Nuclegl1 censing Manager Attachment cc:
A. Bert Davis, NRC Regional Administrator - Rll!
A. Hsia, Project Manager - NRR l
W. Kropp. Senior Resident inspector
[
4NLD/1292/7
\\
/Eo/
e RESPONSE TO NOTICE OF VIOLATION 50-454/91022;455'91022 YLQ!aTION 10 CFR Part 50, Appendix J, Section Ill.A.3.a requires, in part, that all Type A tests be conducted in accordance with the provisions of the American National Standard N45.4-1972 " Leakage Rate Testing of Containment Structures for Nuclear Reactors" March 16,1972. Section 7.8 of this standard requires in part, that pressure, temperature, and humidity observations be made within the containment structure and recorded during the course of the leakage rate test at hourly or more frequent intervals.
Contrary to the above, on September 14.1991, during the conduct of the Type A leakage rate test, data was not recorded from 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> until 2114 hours0.0245 days <br />0.587 hours <br />0.0035 weeks <br />8.04377e-4 months <br />.
B_FAS_ON FOR THE VIOLATION During the performance of the Integrated Leak Rate Test (ILRT) there was a loss of electrical power to the Data Acquisition System (DAS) and the Precision Pressure Monitors (PPMs). The mainframe computer obtains data from the DAS and PPMs at' ten minute intervals. This data is used by the ILRT test personnel to calculate the containment leak rate.
Station operating personnel selectively de-energized breakers in an effort to support the ILRT and a simultaneous maintenance activity. The ILRT instrumentation was understood to be powered from a local electrical outlet. The operating personnel inadvertently opened breakers which supplied power to the DAS and PPMs causing an interruption in data acquisition from 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> to 2112 hours0.0244 days <br />0.587 hours <br />0.00349 weeks <br />8.03616e-4 months <br />.
ILRT testing personnel are required by procedure to record the obtained data in the
. test document every hour. The loss and subsequent restoration of power caused the required time to be exceeded by 12 minutes which is contrary to the requirements of
' Appendix J.
CDBBEGILVE_ST_EESIHAT_HAVE BEE" TAKEN ANDBESULTSACHIEVED An immediate investigation resulted in the appropriate breakers being restored and power was returned to the DAS and PPfAs.
ILRT test personnel recognized the requ; red time for data acquisitior had been exceeded by 12 minu;es and called an NRC Region til representative at 2200, on 9/14/91. A discussion ensued as to the acceptability of continuing the test or if it was necessary to restart the test. The NRC meresentative stated that it would be acceptable to continue the test if continv. of all test data parameters could be shown before the loss of power and after pow -,or a tion ZNLD/1333/2
7
- Sets of' data taken at ten (10) minute intervals were acquired after power restoration.
All of the thermistors and dewcells were tracking as expected, without signs _of the transient. However, the two pressure channels were reading lower than expected.
Both pressure channels recovered to the expec ted pressure decay curves one hour after power restoration.
At.2245 on 9/14/91, a second NRC representa*ive contacted the ILRT test personnel for test status. The ILRT testing personnel provided the current status including the _
recovery from the loss of power. The second NRC representative then concurred that the test could be continued if the pressure channels continued to follow the expected pressure decay curve. It was recommended that this update be passed on to the first NRC contact for concurrence. The ILRT personnel made the contact and received concurrence that the test did not need to be restarted.
The test was completed after successtut acquisition of additional data and demonstration by station personnel that loss of power did not adversely affect the test results.
C_QSB ECIlXEJIE P_SlHATRI.LL B E E K E N_T.O_AVOlD_EU BIB E B_VIO LATIO N 1/2 BVS 6.1.2.a-1. Primary Containment Type A Integrated Leakage Rate Test (ILRT),
will be revised to contain procedural steps defining the power sources to the instrumentation and safeguards to prevent unintentional mispositioning of breakers.
Additionally. the revision will require that test equipment operability is verified by test personnel at _15 minute intervals to ensure proper instrumentation support during the-statistical leak rate and verification test executions. _This revision and training of appropriate operating and testing personnel will be completeo by 8/30/92, which is prior to the next ILRT performance.
An Uninterruptable Power Supply (UPS) will be purchased to ensure power is supplied to the ILRT instrumentation for short durations. This UPS will also provide a filtering function to minimize problems to the equipment caused by power spikes. The UPS will be installed and appropriate training of testing personnel completed by 8/30/92.
DATE WHEN FULL COMPLIANCE WILL_BE ACHIEVEQ Full compliance was achieved on 9/14/91 following successful completion of the test ZNLD/1333 3 e.
s
- --