05000397/LER-2007-001, Regarding Automatic Depressurization System Logic Signal Instrument Inadvertently Disabled
| ML071420042 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 05/15/2007 |
| From: | Oxenford W Energy Northwest |
| To: | Document Control Desk, Plant Licensing Branch III-2 |
| References | |
| GO2-07-085 LER 07-001-00 | |
| Download: ML071420042 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(b)(2)(ii) |
| 3972007001R00 - NRC Website | |
text
W. Scott Oxenford ENERGYTechnical Services ENERGY P.O. Box 968, Mail Drop PE04 Richland, WA 99352-0968 Ph. 509-377-4333 F. 509-377-2354 wsoxenford@energy-northwest.com May 15, 2007 G02-07-085 10 CFR 50.73 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001
Subject:
COLUMBIA GENERATING STATION, DOCKET NO. 50-397 LICENSEE EVENT REPORT NO. 2007-001-00
Dear Sir or Madam:
Transmitted herewith is Licensee Event Report No. 2007-001-00 for Columbia Generating Station. This report is submitted pursuant to 10 CFR 50.73(a)(2)(i)(B). The enclosed report discusses items of reportability and corrective actions taken.
There are no commitments being made to the NRC by this letter. If you have any questions or require additional information, please contact Mr. GV Cullen at (509) 377-6105.
Respectfully, Vice Pr*
ent, Technical Services Mail Drop PE04
Enclosure:
Licensee Event Report 2007-001 -00 cc: BS Malleft - NRC RIV CF Lyon - NRC NRR INPO Records Center NRC Sr. Resident Inspector - 988C (2)
RN Sherman - BPA/1 399 WA Horin -Winston & Strawn CE Johnson - NRC RIV/fax
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 6130/2007 (6-2004)
, the NRC may digits/characters for each block) not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Columbia Generating Station 05000397 1 OF3
- 4. TITLE Automatic Depressurization System Logic Signal Instrument Inadvertantly Disabled
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR FACILITY NAME DOCKET NUMBER NUMBER NO 0500 March 21 2007 2007 - 001 - 00 May 15 2007 FACILITY NAME DOCKET NUMBER 0500
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
Mode 1 El 20.2201(b)
El 20.2203(a)(3)(i)
El 50.73(a)(2)(i)(C)
El 50.73(a)(2)(vii)
El 20.2201(d)
E-20.2203(a)(3)(ii)
El 50.73(a)(2)(ii)(A)
[E 50.73(a)(2)(viii)(A)
[E 20.2203 (a)(1)
El 20.2203(a)(4)
[I 50.73(a)(2)(ii)(B)
El 50.73(a)(2)(viii)(B)
El 20.2203(a)(2)(i)
El 50.36(c)(1)(i)(A)
El 50.73(a)(2)(iii)
[I 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL E-20.2203(a)(2)(ii)
[I 50.36(c)(1)(ii)(A)
El 50.73(a)(2)(iv)(A)
[I 50.73(a)(2)(x) 100%
El 20.2203(a)(2)(iii)
E-50.36(c)(2)
[1 50.73(a)(2)(v)(A)
[1 73.71(a)(4)
El 20.2203(a)(2)(iv)
[I 50.46(a)(3)(ii)
E-50.73(a)(2)(v)(B)
El 73.71(a)(5)
El 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A)
[E 50.73(a)(2)(v)(C)
El OTHER El 20.2203(a)(2)(vi)
[
50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D)
Specify in Abstract below or in (If more space is required, use additional copies of NRC Form 366A)
Plant Conditions
At the time of discovery, Columbia Generating Station was operating in mode 1 at 100%
power. There were no other structures, systems, or components inoperable at the time that contributed to the condition.
Event Description
On March 2 1st, 2007, at approximately 0214, it was discovered that a pressure sensing instrument [PS] had been isolated and out of service during the time it was required to be operable by plant Technical Specifications. The instrument provides a low pressure Emergency Core Cooling System (ECCS) [BO] pump running permissive signal for initiation of Division I of the Automatic Depressurization System (ADS) and is specified in Function 4.e of Table 3.3.5.1-1 in Technical Specifications Limiting Condition for Operation (LCO) 3.3.5.1.
The instrument was discovered isolated during surveillance testing and maintenance records indicate it had potentially been isolated for as long as 32 days. This is longer than the 8-day Completion Time allowed for Required Action G.2 of Technical Specifications LCO 3.3.5.1 to restore operable status.
Immediate Corrective Action
The pressure instrument was promptly restored to service upon discovery of the condition.
Correct pressure instrument valve configuration was verified for all channels in both divisions of ADS.
Cause
Several instances associated with surveillance testing were identified which presented opportunities for the instrument to be isolated by plant technicians or operators. However, no specific evidence or interview information could exclude or identify the specific instance when the inadvertent isolation occurred. Because of this, further cause analysis to identify the specific human error and its causes is not possible.
The cause of the required pressure sensing instrument being inadvertently isolated and out of service is considered to be related to human performance. A discussion pursuant to § 50.73(b)(2)(ii)(J) to support understanding of human performance factors to the extent they apply is provided.
Procedural deficiencies associated with the mispositioned valve included an inservice test procedure that had human factor deficiencies because it did not provide specific valve manipulation instructions or specify a location for connecting and disconnecting a test gauge used for measuring pump discharge pressure. Additionally, a surveillance procedure was found to have human factor deficiencies in that the noun identifier in the procedure for the instrument isolation valve was different 26158 R3U.S. NUCLEAR REGULATORY COMMISSION (1-2001)
LICENSEE EVENT REPORT (LER)
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE YEAR SEQUENTIAL REVISION Columbia Generating Station 05000397 NUMBER NUMBER 3 OF 3 2007-001-00 than the one used on the valve identification tag.
A minor human-system interface deficiency was noted in that the mis-positioned isolation valve had two labels. One label displayed the valve number and one displayed the noun name of the valve.
This creates an additional step when applying the touch-read-read error prevention tool.
Circumstantial aspects of this event are that the personnel involved are non-licensed equipment operators and instrument technicians and there was no indication of any time or situational pressures involved with the testing activities.
Assessment of Safety Consequences
There were no safety consequences associated with this event.
During the entire time the pressure instrument was inadvertently isolated and out of service, redundant instruments were operable to provide initiation capability of both ADS subsystems.
Further Corrective Actions Actions will be taken to correct the human factor deficiencies in the procedures and the human-system interface deficiency associated with the valve labeling.
Previous Similar Events
There have been no previous similar events in which an instrument providing an input to the ECCS system actuation logic had been inadvertently valved out of service for a period of time that exceeded Technical Specifications requirements.
EIIS Information (Denoted as [XX])
Emergency Core Cooling System [BO]
Pressure Switch [PS]
26158 R3