ML18152A845

LER 88-004-00:on 880216,reactor Coolant Dose Exceeded Tech Spec Limit.Caused by Fuel Element Defect in Reactor Core. Level of dose-equivalent I-131 Monitored at Least Every 4 H Until Level Returned to Less than 1 mCi.W/880304 Ltr

ML18152A845
Person / Time
Site:	Surry
Issue date:	03/04/1988
From:	BENSON D L VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
88-005, 88-5, LER-88-004, LER-88-4, NUDOCS 8803140290
Download: ML18152A845 (4)

Text

POW 28-06-01 NRC Form 366 (9-831 LICENSEE EVENT REPORT (LER) U.S. NUCLEAR REGULATORY COMMISSION APPROVED 0MB. NO. 3150-0104 EXPIRES: 8131188 FACILITY NAME (11 PAGE (31 Surrv Power Station Unit 1 !DOCKET NUMBER (21 o 15 I o Io I O I? I R In , loF o I 3 TITLE (41 Iodine Soike Due To Defective Fuel Element EVENT DATE 161 LER NUMBER (61

• REPORT DATE (71 OTHER FACILITIES INVOLVED (81 MONTH DAY YEAR YEAR {}: SE~~~~r~AL (t MONTH DAY YEAR FACILITY NAMES. DOCKET NUMBER(SI ol21IG a a sls-olol4-oloob ol4*sls OPERATING THIS REPORT IS SUBMITTED PURSUANT TO .THE REQUIREMENTS OF 10 CFR §: (Ch*ck on* or more of the follovying/

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LICENSEE CONTACT FOR THIS LER !121 NAME TELEPHONE NUMBER AREA CODE D. L. Benson, Station Manager 81 01 4 31 5 I 7 I -13 I 1 I 8 I 4 CAUSE SYSTEM COMPONENT I I I I I I I I COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13) TURER I I I I I I R~60~ltitE iif:iiiii!i!i!i!i!ii!i!ii!i:i!i!!!!!!ii!!!:!i!iii!i!:

CAUSE SYSTEM I 1 COMPONENT MANUFAC-TURER I I I I I I I I I I I I SUPPLEMENTAL REPORT EXPECTED (141 MONTH DAY YEAR EXPECTED SUBMISSION I YES (If yes, complete EXPECTED SUBMISSION DATE/ DATE (151 I ABSTRACT /Limit ro 1400 spaces, i.e., *pproxim*tely fifteen single-spac*

typ*writton lines/ (161 NRC Farm 386 (9-831 On February 16, 1988 at 1430 hours0.0166 days <br />0.397 hours <br />0.00236 weeks <br />5.44115e-4 months <br />, following a Unit 1 reactor trip, the specific activity sample of the reactor coolant showed a dose equivalent I-131 of 1.17 microcuries/cc.

This exceeds the dose equivalent I-131 Technical Specification of less than 1.0 microcurie/cc specified in Section 3.1.d.2 and is being reported in accordance with the special reporting requirements outlined in Technical Specification 3.1.d.4. The iodine spike was caused by a known, but not specifically located, fuel element defect in the reactor core. Post shutdown conditions enhanced the release of fission products, specifically I-131. This caused an increase in reactor coolant specific activity.

The immediate corrective action was to implement the actions required by Technical Specification Table 4.1.2B. Specifically, the level of dose-equivalent I-131 was monitored at least every four hours until the level returned to less than 1.0 microcurie/cc.

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\\ NRC Form 366A 19-831 FACILITY NAME 111 e LICENSEE EVENT REPORT (LERI TEXT CONTINUATION DOCKET NUMBER 121 POW 28-06-01 U.S. NUCLEAR REGULATORY COMMISSION APPROVED 0MB NO. 3150-0104 EXPIRES: 8/31/88 LER NUMBER 161 PAGE 131 Surry Power Station, Unit 1 o 1s Io Io Io I 2 I al o al a -o I ol 4 -o I n nl? oF n I -::i TEXT /If motW _.,. io ,aquhd, u* !MldltioMI NRC Fann 31511A '1/ 1171 NRC FORM 366A 19-83) 1.0 Description of the Event On February 16, 1988, at 1430 hours0.0166 days <br />0.397 hours <br />0.00236 weeks <br />5.44115e-4 months <br />, following a Unit 1 reactor trip, the specific activity sample of the reactor coolant showed a dose equivalent I-131 level of 1.17 microcuries/cc.

This exceeds the dose equivalent I-131 limit of 1.0 microcurie/cc specified in Technical Specification 3.1.d.2 and is being reported in accordance with the special requirements outlined in Technical Specification 3.1.d.4. 2.0 Safety Consequences and Implications The limitations on*the specific activity of the reactor coolant ensures that the resulting two hour dose at the site boundary will not exceed a small fraction of the 10CFR100 limits following a postulated Steam Generator Tube Rupture (SGTR). Since the equivalent I-131 peak was below the Technical Specification upper limit of 10 microcuries/cc, the reactor coolant gross activity was below the value analyzed in the UFSAR for a SGTR with 1% failed fuel. T~erefore, the health and safety of the public were not affected.

3.0 cause

The iodine spike was caused by a known, but specifically located, fuel element defect in the reactor core. Post shutdown conditions enhanced release of fission products, specifically I-131. caused an increase in reactor coolant specific activity.

4.0 Immediate

Corrective Actions not the This The immediate corrective action was to implement the action*s required by Technical Specification Table 4.1.2B. Specifically, the level of dose-equivalent I-131 was monitored at least every four hours until the level returned to less than 1.0 microcurie/cc.

• U.S.GPO: 1986-0*624-538/455 e NRC Form 3841A (9-831 LICENSEE EVENT REPORT (LER) TEXT CONTINUATION U.S. NUCLEAR REGULATORY COMMISSION APPROVED 0MB ND. 3150-0104 EXPIRES: B/31 /88 FACILITY NAME (11 DOCKET NUMBER (21 LER NUMBER (61 Surry Power Station, Unit 1 TEXT /If_,,._..

b ,eqund, ,,_ ~itioMI NRC Farm .-...**J 1171 Supplemental Information:

The following supplemental information required by Technical Specification 3.1.d.4 11 Special Report 11 is included:

1. Reactor Power History 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> prior to the event: February 14, 1988 @ 0000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> 100% power. February 14, 1988 @ 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> 100% power. February 15, 1988 @ 0000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> 100% power. February 15, 1988 @ 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> 100% power. February 16, 1988 @ 0000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> 100%power.

February 16, 1988@ 1143 hours0.0132 days <br />0.318 hours <br />0.00189 weeks <br />4.349115e-4 months <br /> -Reactor Trip. 2. Fuel burnup by core region as of February 16, 1988. Fuel Batch S2/8A Sl/8B Sl/9A Sl/9B S2/9B Sl/lOA Sl/llA Sl/llB Cycle 9 Burnup: Burnup 36102 MWD/MTU 31644 MWD/MTU 35453 MWD/MTU 35472 MWD/MTU 35028 MWD/MTU 34103 MWD/MTU 17705 MWD/MTU 17137 MWD/MTU 14572 MWD/MTU 3. Prior to the reactor shutdown, the unit had normal letdown rate of 105 gpm. 4. No degassing operations were performed prior to the event. 5. Duration of I-131 Spike: February 16, 1988@ 0455-Routine Sample: .0420 microcuries/cc February 16, 1988@ 1430-Post Shutdown Sample: 1.17 microcuries/cc February 16, 1988@ 1725-Post Shutdown Sample: 0.75 microcuries/cc Event Duration:

Approximately 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />. NRC FORM 386.A (8,831 PAGE 131

• U.S.GPO: 1988*0*1124*538/455

'..,, March 4, 1988 U.S. Nuclear Regulatory Commission Document Control Desk 016 Phillips Building Washington, D.C. 20555 Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY Surry Power Station P. 0. Box 316 Surry, Virginia 23883 Serial No.: Docket No.: Licensee No. : 88-005 50-280 DPR-32 Pursuant to Surry Power Station Technical Specifications, Virginia Electric and Power Company hereby submits the following Licensee Event Report for Surry Unit 1. REPORT NUMBER 88-004-00 This report bas heen reviewed by the Station Nuclear Safety and Operating Committee and will be reviewed by Safety Evaluation and Control. Very truly yours, David L. Benson Station Manager Enclosure cc: Dr. J. Nelson Grace Regional Administrator Suite 2900 101 Marietta Street, NW Atlanta, Georgia 30323