05000280/LER-2003-002, From Surry, Unit 1 Regarding Manual Steam Generator Level Control Results in Power Ascension Reactor Trip

From Surry, Unit 1 Regarding Manual Steam Generator Level Control Results in Power Ascension Reactor Trip

ML030920098
Person / Time
Site:	Surry  (DPR-032)
Issue date:	03/26/2003
From:	Blount R Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
03-198, SPS:BAG/TJN R2 LER 03-002-00
Download: ML030920098 (6)

LER-2003-002, From Surry, Unit 1 Regarding Manual Steam Generator Level Control Results in Power Ascension Reactor Trip

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2) 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)(v), Loss of Safety Function
2802003002R00 - NRC Website

text

1 OCFR50.73 Virginia Electric and Power Company Surry Power Station 5570 Hog Island Road Surry, Virginia 23883 March 26, 2003 U. S. Nuclear Regulatory Commission Serial No.:

03-198 Attention: Document Control Desk SPS: BAG/TJN R2 Washington, D. C. 20555-0001 Docket No.: 50-280 License No.: DPR-32

Dear Sirs:

Pursuant to 10CFR50.73, Virginia Electric and Power Company hereby submits the following Licensee Event Report applicable to Surry Power Station Unit 1.

Report No. 50-280/2003-002-00 This report has been reviewed by the Station Nuclear Safety and Operating Committee and will be forwarded to the Management Safety Review Committee for its review.

Very truly yours, Richard H. Blount, Site Vice President Surry Power Station Enclosure Commitment contained in this letter:

Two Root Cause Evaluation (RCEs) were initiated to determine the causes of these events. The approved recommendations from the RCEs necessary to prevent recurrence will be implemented through the corrective action program.

cc: United States Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW, Suite 23 T85 Atlanta, Georgia 30303-8931 Mr. R. A. Musser NRC Senior Resident Inspector Surry Power Station

NRC FORM 366 U.S. NUCLEAR REGULATORY APPROVED BY OMB NO. 3150-0104 EXPIRES 7-31-2004 (7-2001)

C the NRC may not conduct or sponsor, and a person Is not required to respond to, the information collection FACILITY NAME (1)

DOCKET NUMBER (2)

PAGE (3)

SURRY POWER STATION, Unit 1

.05000 - 280 1 OF4 TITLE (4)

Manual Steam Generator Level Control Results in Power Ascension Reactor Trip EVENT DAT (5)

LER NUMBER (6) l

[ REPORT DAT FT1 I

OTHER FACILITIES INVOLVED (8

)

MONTH DAY YEAR YEAR SEQUENTIAL REVISION MONTH DAY YEAR FACILITY NAME DOCUMENT NUMBER NUMBER NUMBER 05000-01 25 2003 2003

-- 002-00 03 26 2003 FACILITY NAME DOCUMENTNUMBER l l l 11 05000-OPERATING 1 1 THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Checkall that apply) (11)

MODE (9) l N l

l 202201(b) 20 2203(a)(3)(if) 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)

POWER 20.2201(d) 20.2203(a)(4) 50.73(a)(2)(IiI) 50 73(a)(2)(x)

LEVEL (10) 27 20.2203(a)(1) 50.36(c)(1)i)(A)

X 50.73(a)(2)(iy)(A) 73 71(a)(4) 20.2203(a)(2)(i) 50 36(c)(1)(ii)(A) 50.73(a)(2)(v)(A) 73.71 (a)(5) 20.2203(a)(2)(fI) l 50.36(c)(2) 50.73(a)(2)(v)(B)

OTHER 20 2203(a)(2)(iii) l 50 46(a)(3)(ii) 50.73(a)(2)(v)(C)

Specify In Abstract below or

_v In (If more space is required, use additional copies of (If more space is required, use additional copies of NRC Form 366A) (17)

Conclusions from these RCEs will be evaluated and the approved recommendations from the RCEs necessary to prevent recurrence will be implemented through the corrective action program.

7.0 SIMILAR EVENTS

LER 50-281/96-04-00, Turbine/Reactor Trip Due to High Level in the Steam Generator With power escalation in progress for Unit 2, the operators began transferring from manual feedwater flow control to automatic control. At 16% reactor power, a high-high SG 'B' level signal caused a turbine trip and subsequent reactor trip. The root cause of the trip was design interface. Specifically, manual SG level control at low power, combined with other equipment malfunctions, challenged the operating team to the point where the SG level could not be successfully controlled. A design change was implemented to replace the feed regulating valve on Unit 1 as is noted in the above discussions.

8.0 MANUFACTURER/MODEL NUMBER The TDAFWP governor that was replaced was a Woodward PG-PL.

9.0 ADDITIONAL INFORMATION

None