05000445/LER-2002-004, Re Inoperable Train/Channel in Safety Related System
| ML030030720 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 12/30/2002 |
| From: | Walker R TXU Energy |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 10200, CPSES-200203957, TXX-02209 LER 02-004-00 | |
| Download: ML030030720 (7) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 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)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat |
| 4452002004R00 - NRC Website | |
text
k TXU AS,41-TXU Energy Comanche Peak Steam Electric Station P.O Box 1002 (E01)
Glen Rose,TX 76043 Tel. 254 897 8920 Fax 254 897 6652 lance terry@txu corn C. Lance Terry Senior Vice President &
Principal Nuclear Officer Ref: 10 CFR 50.73(a)(2)(vii)
CPSES-200203957 Log # TXX-02209 File # 10200 December 30, 2002 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 SUBJECT: COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
DOCKET NO. 50-445 INOPERABLE TRAIN/CHANNEL IN SAFETY RELATED SYSTEM LICENSEE EVENT REPORT 445/02-004-00 Gentlemen:
Enclosed is Licensee Event Report (LER) 02-004-00 for Comanche Peak Steam Electric Station Unit 1, "Two Pressurizer Safety Valves Found With Unsatisfactory Lift Setpoints."
This communication contains no new licensing basis commitments regarding CPSES Units 1 and 2.
/A/
'y A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway Comanche Peak.
Diablo Canyon Palo Verde South Texas Project Wolf Creek
fo.
ft TXU
'1411.9 TXX-02209 Page 2 of 2 Sincerely, TXU Generation Company LP By:
TXU Generation Management Company LLC, Its General Partner C. L. Terry Senior Vice President and Principal Nuclear Officer By:
Red P
V/
Roger
. Walker Regulatory Affairs Manager RJK/clc Enclosure c -
E. W. Merschoff, Region IV W. D. Johnson, Region IV D. H. Jaffe, NRR Resident Inspectors, CPSES
Enclosure to TXX-02209 NRC FORM 366 US NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 31504104 (7i-201X)
EXPIRES 07t31t2004 the NRC may not conduct or Facility Name (1)
Docket Number (2)
Page (3)
COMANCHE PEAK STEAM ELECTRIC STATION UNIT 1 05000445 1 OF 5 Ttle (4)
TWO PRESSURIZER SAFETY VALVES FOUND WITH UNSATISFACTORY LIFT SETPOINTS Event Date (5)
LEt RNumber (6 R' nrt Date (7)
Other Facilities Involved (8)
Month Day Year Year Sequential Revision Month Day Year FacilityName Docket Numbers Number Number 10 30 02 02 004 00 12 30 02 05000 Operating Tis report is submtted pusuar to the requirements of 10 CFR * (Check all that appYl) (II)
Mode (9) 20.2201(b) 20 2203(a)(3)(1) 50 73(a)(2)()(C)
X 50.73(a)(2)(vii)
Power 20 2201 (d) 20 2203(a)(3)(h) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 0 20 2203(a)(1) 20 2203(a)(4) 50 73(a)(2)(ii)(13) 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 50.36(c)(2)(i)(A) 5073(a)(2)(iii) 50.73(a)(2)(ix)(A) 20 2203(a)(2)(ii) 50 36(c)(1)(ii)(A) 50 73(a)(2)(iv)(A) 50.72(a)(2)(x) 20 2203(a)(2)(iii) 50 36(c)(2) 50 73(a)(2)(v)(A) 73.71 (a)(4) 20 2203(a)(2)(iv) 50 46(a)(3)(ii) 50.73(a)(2)(v)(B) 73.71 (a)(5)
P 20 2203(a)(2)(v) 50 73(a)(2)(i)(A) 50 73(a)(2)(v)(C)
OTHER t
20 2203(a)(2)(vl)
X 50 73(a)(2)(i)(B) 50 73(a)(2)(v)(D)
Specify in Abstract below or
______VX____1>_
_in (If more space is required, use additional copies of SUMMARY OF THE EVENT, INCLUDING DATES AND APPROXIMATE TIMES On October 5, 2002, the Pressurizer Safety Valves (PSVs) were removed from the system and were sent off-site to NWS Technologies for surveillance testing in support of the ninth refueling outage on Comanche Peak Unit 1. Testing was performed using a procedure designed to comply with ASME/ANSI OM-1987 Part 1 and Westinghouse Owner's Group guidance, using saturated steam as the test medium.
On October 6,2002, the as-found lift of PSV 1-8010A was 2436 psig, which is 2.0% below the Technical Specification 3.4.10.1 setpoint of 2485 psig, which specifies a plus or minus 1%
range. On October 7, 2002, the as-found lift of PSV 1-8010B was 2446 psig, which is 1.6%
below the Technical Specification setpoint. PSV 1-8010C was found with an acceptable setpoint. Both of the unsatisfactory PSVs were reworked by the vendor and the as-left lift pressures were verified to be within Technical Specification limits. The PSVs were (If more space is requirae use addutonal copies of (If more space is requred use addeional copies of (If more space is required. use additional copies of NRC Form 366A) (17)
IV.
CAUSE OF THE EVENT
Based on a failure analysis evaluation, performed by CPSES Engineering Programs personnel based on experience with these valves, the root cause was determined to be setpoint drift. A specific cause of the setpoint drift could not be determined. The test results were within the 3% acceptance range of ASME/ANSI OM-1987 Part 1. Per past discussions with the valve vendor, deviations within this range are within the design requirements of the valve and do not indicate a material problem with the valves. This conclusion is further supported by the fact that the valves demonstrated satisfactory test results after adjustment.
V.
CORRECTIVE ACTIONS
Maintenance was performed by the vendor on both PSVs before retesting in order to restore them to the required lift setpoints. On October 23, 2002, the required surveillances were completed satisfactorily, with all three PSVs being tested satisfactorily to state-of-the-art requirements identified through the Westinghouse Owners Group program.
VI.
PREVIOUS SIMILAR EVENTS
Three previous similar events have been reported for CPSES pursuant to 10CFR50.73(a)(2)(vii), LER 445/91-026 on Unit 1, LER 446/94-018 on Unit 2, and LER 445/96-08 on Unit 1.
The initial event, LER 445/91-026, resulted from use of an inadequate test method, while the two subsequent events were a result of setpoint drift of a magnitude within the design requirements of the valves, similar to the current event.
NRC FUOM 366A (1-2001)