05000361/LER-2004-001, Re Personnel Error Results in Technical Specification Violation During Movement of Irradiated Fuel
| ML041250032 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 04/29/2004 |
| From: | Waldo R Southern California Edison Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LER 04-001-00 | |
| Download: ML041250032 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3612004001R00 - NRC Website | |
text
SOUTHERN CALIFORNIA EDISONt An EDISO.\\I I'7-RAIA'O 0.V,1L( Conipans Dr. Raymond W. Waldo Station Manager San Onofre April 29, 2004 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555
Subject:
Docket No. 50-361 Licensee Event Report No. 2004-001 San Onofre Nuclear Generating Station Unit 2 Gentlemen:
This submittal provides Licensee Event Report (LER) 2004-001 describing a personnel error that resulted in a Technical Specification violation during movement of irradiated fuel in the Unit 2 Fuel Handling Building. This event did not affect the health and safety of either plant personnel or the public.
Any actions listed in this LER are intended to ensure continued compliance with existing commitments as discussed in applicable licensing documents; this LER contains no new commitments. If you require any additional information, please so advise.
Sincerely, Enclosure cc:
B. S. Mallett, Regional Administrator, NRC Region IV C. C. Osterholtz, NRC Senior Resident Inspector, San Onofre Units 2 & 3 P.O. Box 128 San Clemente, CA 92672-0128 949-368-8725/PAX 88725 Fax 949-368-6183 waldorw@songs.sce.com
Abstract
On 3/6/04, Unit 2 was in a refueling outage and operators were preparing to reload the core. Prior to moving irradiated fuel in the Fuel Handling Building, operators placed PACU Train "A" in operation in accordance with LCO 3.7.14, Action B.1, because Train "B" was inoperable. The Train "A" PACU was placed in operation in parallel mode, in which the normal HVAC system remained in service. Parallel operation is allowed by the Bases to LCO 3.7.14, Action B. 1, if two channels of Fuel Handling Isolation Signal (FHIS) are operable. Fuel movement started at 1355 PST on 3/6/04. At 2230 PST on 316/04, Train "B" FHIS Radiation Monitor 2RT-7823 was removed from service for a scheduled electrical bus outage. At that time, Operators did not recognize that, with one FHIS channel inoperable, the normal HVAC should have been stopped and PACU Train "A" placed in isolate mode.
At 0650 PST, on 317/04, Operators discovered this error, suspended movement of irradiated fuel, and placed PACU Train "A" in isolate mode. SCE is reporting this event in accordance with 1 OCFR50.73(a)(2)(i)(B).
This event was caused by personnel error. Operators failed to review the procedural requirements for the movement of irradiated fuel prior to removing 2RT-7823 from service. Appropriate communications and personnel action have been taken. SCE plans to enhance applicable procedures.
NRC FORM 366 (7-2001)U.S. NUCLEAR REGULATORY COMMISSION (7-2001)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION
- 1. FACLITY NAME
- 2. DOCKET NUIBER S. LER NUM1ER PAE (3) 3 YEAR lSEQUENTIAL REVNO San Onofre Nuclear Generating Station (SONGS) Unit 2 05000-361 YER I
NUMBER 2 ofV 4 1
2004 1
- - 001 --
I0 2o Plant:
San Onofre Nuclear Generating Station (SONGS), Unit 2 Event Date:
March 6, 2004 Unit 2 Reactor Vendor:
Combustion Engineering Power:
0 percent
Background:
The function of the Fuel Handling Building (FHB) [ND] Post-Accident Cleanup Filter System (PACU) [VG] is to filter airborne radioactive particulates and gases from the area of the fuel pool following a postulated fuel handling accident. The PACU, in conjunction with normally operating systems, also provides environmental control of temperature in the fuel pool area.
Technical Specification (TS) 3.7.14, Fuel Handling Building Post-Accident Cleanup Filter System, requires two trains to be operable during movement of irradiated fuel assemblies within the FHB.
With one train of PACU inoperable, Action A requires the inoperable train be restored to an operable condition within 7 days. If Action A is not met, Action B requires either (1) placing the operable train of PACU into operation immediately, or (2) suspending the movement of irradiated fuel within the FHB immediately. SONGS is allowed to remain in Action B indefinitely.
The PACU has two modes of operation applicable to Action B. 1, as described in the Bases to TS 3.7.14:
- 1. In "Parallel" mode, the PACU operates concurrently with the normal FHB ventilation system (VG]. This mode of operation is allowed only if both Fuel Handling Isolation Signal (FHIS) [IL] channels are operable, including isolation logic circuits and associated Radiation Monitors, 2RT-7822 [RIT] and 2RT-7823.
- 2. In "Isolate" mode, the normal FHB ventilation system is secured and the operable PACU remains operating in a recirculation configuration. This mode of operation is required if one FHIS channel is inoperable while moving irradiated fuel.
Description of the Event:
On March 6, 2004, Unit 2 was preparing to commence the reactor core reload during the Cycle 13 Refueling Outage. At approximately 0415 PST, prior to initiating movement of irradiated fuel within the FHB, PACU Train "A" was placed in operation in parallel mode because the PACU Train 'B" was inoperable. Both FHIS radiation monitors were operable at that time.
At approximately 1355 PST on March 6, 2004, Operators began moving irradiated fuel within the FHB. Later on the same day, at approximately 2230 PST, the Train "B" FHIS Radiation Monitor 2RT-7823 was removed from service in support of a scheduled electrical bus outage. The Train "A" PACU continued operating in the parallel mode.
At 0650 PST, on March 7, 2004, movement of irradiated fuel within the FHB was suspended after the Shift Technical Advisor (utility, licensed) recognized the PACU configuration did not satisfyU.S. NUCLEAR REGULATORY COMMISSION (7-2001)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION
- 1. FACILITY NAME I
DOCKET NUMBER I
- 6. LER NUMBER PAGE 131 S
YEAR SEQUENTLAL REV NO San Onofre Nuclear Generating Station (SONGS) Unit 2 05000-361 1
NUMBER 13 of 4 112004 1
- - 001 -
I0 LCO 3.7.14, Action B.1. Operators immediately placed the Train "A" PACU in the isolate mode.
Fuel movement in support of the core reload resumed shortly thereafter.
SCE is reporting this occurrence in accordance with 10 CFR 50.73(a)(2)(i)(B).
Cause of the Event
This event resulted from personnel error. The Control Operator (utility, licensed) and Control Room Supervisor (utility, licensed) who were preparing to remove FHIS Radiation Monitor 2RT-7823 from service incorrectly concluded that the requirements for movement of irradiated fuel within the FHB were unaffected by the inoperability of a single FHIS channel. Although the operators discussed the existing plant configuration, they failed to review the Operating Instruction that establishes the requirements for movement of irradiated fuel within the FHB. Had the operators reviewed the procedure, they would have been directed to place the operating PACU in the isolate mode.
Corrective Actions
The following immediate actions have been taken:
The supervisor involved with this event has been counseled; A required reading assignment on this event was issued to all operators; and The Limiting Conditions for Operation Action Requirement (LCOAR) template for the PACU has been improved to provide explicit direction for meeting the requirements for fuel movement with one train inoperable.
Additionally, applicable Operating Instructions will be enhanced to:
- Clarify the restrictions for PACU operation described in the Bases to TS 3.7.14;
- Explicitly define the operating requirements of the PACU with one train inoperable; and
- Prescribe actions to be taken when the status of the PACU or FHIS trains change when fuel movement is in progress or imminent.
Planned actions will be completed prior to the Unit 3 Cycle 13 Refueling Outage, which is currently scheduled to begin in September 2004.U.S. NUCLEAR REGULATORY COMNMISSION (7-2001)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION
- 1. FACLITY NAME
- 2. DOCKET NUBER
- 6. LER NUMEER PAGE (3)
SanYEAR SEQUENTIAL N REV NO San Onofre Nuclear Generating Station (SONGS) Unit 2 I05000-361 2004 NMBE f
4 of 4
Safety Significance
The PACU is used to mitigate the consequences of a fuel handling accident in the FHB.
However, this event had minimal safety significance because:
The fuel handling accident analysis does not credit the PACU operation for dose mitigation; One train of PACU was operating to mitigate a fuel handling accident; One FHIS channel was operable and able to isolate the FHB if a fuel handling accident occurred; and
- This event was not caused by nor did it result in a Safety System Functional Failure (SSFF). This event did not impact the ability to shut down the Unit or mitigate the consequences of an accident.
Additional Information
SONGS reported a similar event at Unit 3 in LER 2001-002. On January 20, 2001, during refueling, SCE personnel initiated transfer of irradiated fuel from the FHB to the containment with PACU Train "B" inoperable. At that time, Train WA" was not placed into operation, as required by LCO 3.7.14, Action B.1. The event occurred because the TS requirements had not been correctly reflected in applicable Operating Instructions. For the case reported herein, the procedures were correct but not consulted by the individual operators.