05000219/LER-2002-001, Plant Operations Outside of Technical Specifications Due to a Degraded System
| ML021580298 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 05/23/2002 |
| From: | Degregorio R AmerGen Energy Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 2130-02-20139 LER 02-001-00 | |
| Download: ML021580298 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(ii) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(iv), System Actuation 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability |
| 2192002001R00 - NRC Website | |
text
AmerGen SM AmerGen Energy Company, LLC An Exelon/British Energy Company Oyster Creek US Route 9 South P.O. Box 388 10 CFR 50.73(a)(2)(i)
Forked River, NJ o8731-0388 May 23, 2002 2130-02-20139 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington DC 20555
Subject:
Oyster Creek Nuclear Generating Station Docket No. 50-219 Licensee Event Report 02-001:
Plant Operations Outside of Technical Specifications Due To A Degraded System Enclosed is Licensee Event Report LER 02-001. This event did not affect the health and safety of the public.
If any additional information or assistance is required, please contact Mr. John Rogers of my staff at 609.971.4893.
Very truly yours, Ron J. D Vice President, Oyster Creek RJD/JJR cc:
Administrator, Region I NRC Project Manager Senior Resident Inspector
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (4-95)
APPROVED BY OMB NO. 3150-0104 EXPIRES 04/30/98 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS MANDATORY INFORMATION COLLECTION REQUEST: 50.0 HRS. REPORTED LESSONS LEARNED ARE INCORPORATED INTO T LCENSING PROCESS AND FED BACK TO INDUSTRY.
FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION AND RECORDS MANAGEMENT BRANCH (T-6 F33), U.S. NUCLEAR LICENSEE VENREGULATORYER)COMMISSION, WASHINGTON, DC 20555-0001, AND TO THEI LICENSEE EVENT RtPORT (LER)
PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.
FACILITY NAME (1)
DOCKET NUMBER (2)
PAGE (3)
Oyster Creek Unit 1 05000-219 1 of 4 Plant Operations Outside of the Technical Specifications due to a Degraded System EVENT DATE (5)
LER NUMBER (6)
REPORT DATE (7)
OTHER FACILITIES INVOLVED (8)
MONTH Y
AR YEAR SEQUENTIAL REVIS IMONT FACILITY NAME DOCKET NUMBER N
BNUMBER ONlE
___05000 03 26 02 02 01 00 05 23ACILITYNAME OCKET NUMBER 05000 OPERATING N
- - THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 8: (Check one or more) (11)
MODE (9) 20.2201(b) 20.2203(a)(2)(v)
X 50.73(a)(2)(i) 150.73(a)(2)(vmi)
POWER 100
__ 20.2203(a)(I) 20.2203(a)(3)(i) 50.73(a)(2)(ii) 150.73(a)(2)(x)
LEVEL (10) T l
20.2203(a)(2)(i)
- 20. 2203(a)(3)(ii)
T50.73(a)(2)(iii) 173.71 20.2203(a)(2)(ii) 20.2203(a)(4) 50.73(a)(2)(iv)
I JOTHER 20.2203(a)(2)(iii) 50.36(c)(1) 50.73(a)(2)(v) r-g 20.2203(a)(2)(iv)
I l50.36(c)(2) l 50.73(a)(2)(vii)
LICENSEE CONTACT FOR THIS LER (12)
NAME rELEPHONE NUMBER (Include Area Code)
John Rogers 1
609.971.4893 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
CAUSE
SYSTEM COMPONEN MANUFACTU REPORTAB
CAUSE
SYSTEM COMPONEN IMANUFACTUR IREPORTABIL T
RER LE T
ER E
l l
l TO EPIX
____l____
TO NPRDS; B
IL EHTR GE y
SUPPLEMENTAL REPORT EXPECTED (14)
EXPECTED SIINO 1
SUBMISSION Pete EXPECTED SUBNESSION DATE)-
1DATE (15)
ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)
At 7:00 AM on March 23, 2002, a sufficient volume of water had condensed in the Offgas Radiation Monitor sample chamber to cause the monitor to read unacceptably low. This resulted in the monitor being incapable of performing its intended function of isolating the Off Gas Line if Technical Specification release limits were exceeded.
The sample chamber heat trace had failed allowing moisture to accumulate in the sample chamber.
The system engineer, in response to a maintenance request, developed a troubleshooting plan which included a procedure to remove moisture from the sample chamber. On April 9, 2002, at 5:49 PM, draining was commenced on the sample chamber. Upon the draining of the chamber, indications returned to normal. The system was declared operable at 7:25 PM.
The cause of the Technical Specification violation was a failed sample chamber heat trace. The heat trace was restored to an operable condition. The safety significance of this occurrence was minimal. Although the Air Ejector Offgas Radiation Detection System was inoperable, the Stack Radioactive Gaseous Effluent Monitoring System was in operation. No unexpected activity was noted. Weekly samples performed by the chemistry department of air ejector offgas did not show an increase in offgas activity.
NRC FORM 366 (4-95)U.S. NUCLEAR REGULATORY COMMISSION (4-95)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1)
DOCKET (2)
LER NUMBER (6)
PAGE (3) 05000 I SEQUENTIAL REV 05000NUMBE Oyster Creek,Unit
- - 219 l02 --
01 00 2
of 4
TEXT (If more space is required, use additional copies of NRC Form 366A) (17)
DATE OF DISCOVERY On April 25, 2002, a review of system performance determined the Technical Specification Limit for the Offgas Radiation Monitor Out of Service time had been exceeded on March 26, 2002.
IDENTIFICATION OF OCCURRENCE At approximately 7:00 AM on March 26, 2002, a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Technical Specification out of service allowance expired but a reactor shutdown was not commenced. This occurrence is considered reportable under 10 CFR 50.73(a)(2)(i).
CONDITIONS PRIOR TO DISCOVERY The plant was operating at 100% power with all temperatures and pressures normal for full power operation.
DESCRIPTION OF OCCURRENCE Before main condenser (EIIC - COND) air ejector offgas is discharged to the environment, a sample stream is passed through a six-foot section of four inch, internally polished, stainless steel pipe. Two ion chamber radiation detectors (EIIS - IL) monitor this sample chamber. At 7:00 AM on March 23, 2002, a sufficient volume of water had condensed in the Offgas Radiation Monitor sample chamber to cause the monitor to read unacceptably low. Although both detectors passed all Technical Specification required surveillances, the water resulted in the monitor being incapable of performing its intended function of isolating the offgas line if the Technical Specification release limits were exceeded. On April 7, 2002, the operators questioned the lower than normal Offgas Radiation Monitor readings and a Corrective Action Program document was issued. An inspection of the Air Ejector Offgas Sample Line for air leaks (which were thought to be the cause of the indications) was conducted. No air leaks were discovered. The downward trend continued and on April 9, 2002, at 1:28 PM, the Shift Manager declared the system inoperable, entered a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Technical Specification out of service allowance, and documented the abnormal radiation trend in a maintenance request.U.S. NUCLEAR REGULATORY COMMISSION (4-95)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1)
DOCKET (2)
LER NUMBER (6)
PAGE (3) 05000 NUMBER R
Oyster Creek, Unit 1
- - 219 02 --
001 00 3
of 4
TEXT (If more space is required, use additional copies of NRC Form 366A) (17)
DESCRIPTION OF OCCURRENCE (Cont.)
The system engineer, in response to the maintenance request, developed a troubleshooting plan which included a procedure to remove moisture from the sample chamber and initiated an Action Request to check the sample chamber heat trace (ElIC - EHTR). On April 9, 2002, at 5:49 PM, draining was commenced on the sample chamber. Indications returned to normal and the system was declared operable at 7:25 PM.
Subsequently, on April 25, 2002, an evaluation of monitor performance was completed and it was concluded that the monitor had become inoperable on March 23, 2002 at 7:00AM and continued in excess of the Technical Specification out of service allowance.
FAILURE DATA General Electric; electrical heat trace.
APPARENT CAUSE The failure of the sample chamber heat trace in the Air Ejector Off Gas sample system resulted in moisture collecting in the sample chamber. As water collected in the chamber, a decrease in offgas radiation indications occurred due to the displacement of the monitored gas away from the detectors.
A contributing cause was determined to be insufficient administrative controls to evaluate component degradation.
ANALYSIS OF OCCURRENCE AND SAFETY ASSESSMENT The safety significance of this occurrence was minimal. Although the Air Ejector Offgas Radiation Detectors were inoperable, the Stack Radioactive Gaseous Effluent Monitoring System was in operation. No unexpected activity was noted. Weekly samples performed by the chemistry department of air ejector offgas did not show an increase in offgas activity. Additionally the main steam line radiation detectors were in operation and did not indicate any fuel element failure. The plant remained within the Technical Specification Release Limits at all times. There was no unexpected radioactive release and thus there was no effect on the health and safety of the public.(4-95)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1)
Oyster Creek, Unit 1 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)
CORRECTIVE ACTIONS
Immediate Corrective Actions Upon recognizing that the detection system was degraded, the sample chamber was drained and enhanced monitoring was commenced.
Short Term Corrective Actions It was determined that the cause of the water buildup was a failure of the sample chamber heat trace.
New administrative controls have been initiated to evaluate detection system performance. If monitoring of these additional parameters indicates that the detection system performance has degraded, the sample chamber will be drained.
The heat trace was replaced and the radiation monitoring system restored to full operability on May 8, 2002.