ML18152A710

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LER 87-034-00:on 871126,specific Activity Sample of Reactor Coolant Showed Dose Equivalent I-131 of 1.19 Uci/Cc.Caused by Fuel Element Defect in Reactor Core.Required Tech Spec 4.1.2B implemented.W/871222 Ltr
ML18152A710
Person / Time
Site: Surry Dominion icon.png
Issue date: 12/22/1987
From: Benson D
VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
87-039, 87-39, LER-87-034, LER-87-34, NUDOCS 8712310213
Download: ML18152A710 (4)
v • d • e


Text

POW 28-06-01 NRC Form 366 U.S. NUCLEAR REGULATORY COMMISSION (9-83)

APPROVED OMa NO. 3150-0104 LICENSEE EVENT REPORT (LER) EXPIRES: 8/31/88 FACILITY NAME (1) DOCKET NUMBER (21 PAGE (3)

TITLE (41 Surrv Power Station, Unit 1 IO Is I O IO IO I 21 81 d 1 loF nI 3 Iodine Spike Due To Defective Fuel Element EVENT DATE (5) LEA NUMBER (6) REPORT DATE (71 OTHER FACILITIES INVOLVED (81 MONTH DA'i YEAR YEAR f:::::::::: SEQUENTIAL!::::::::: REVISION MONTH DAY YEAR FACJ LITY NAMES DOCKET NUMBERISI

!:::::::::: NUMBER t::::::::: NUMBER d314 olo 11: sl7

,112168 7 817-OPERATING MODE (8)

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THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 20.402(b)

....._ 20.405(c) 212

§: (Check one or more of the follo"(ing) 111) 50.73(a)(2){iv) 73.71(b)

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20.4051*)(1 ){i) 20.405(a){1)(ii) -- 60.38(c)(1) 50.38(c)(2) -- 50.73lo)(2llvl 50.73(o)(2)(vii) 73.71 (cl OTHER (Specify in Abstr*ct b~low snd in Text, NRC Form llllllltiilllll~

20.406l*H1 Hiiil 50.73(a)l2)(i) 50.73(a)l2)(viii)IA) 366A) 20.405(a)(1)(1v) 20.40510)11 )(v) - 60.73(1)(2){ii) 50.73(1)(2)(iiil LICENSEE CONTACT FOR THIS LEA (121 50.73(a){2)lviii)(BI 50.73(ol 12Hx)

"Special Report" NAME TELEPHONE NUMBER AREA CODE D. L. Benson, Station Manager COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

MANUFAC- MANUFAC-CAUSE SYSTEM COMPONENT SYSTEM COMPONENT TURER TURER I I I I I I I I I I I I I I I I I I I I I I I I I I I I SUPPLEMENTAL REPORT EXPE'CTED (141 MONTH OAY YEAR EXPECTED n YES (If yas, complete EXPECTED SUBMISSION DA TE)

SUBMISSION DATE 1151 I I I ABSTRACT {Limit to 1400 spaces, i.e., approximately fiftetJn single-space typewritten lines) (161 On November 26, 1987, at 0415 hours0.0048 days <br />0.115 hours <br />6.861772e-4 weeks <br />1.579075e-4 months <br />, following a Unit 1 shutdown for repairs to Steam Generator 'C 1 secondary manway, the specific activity sample of the reactor coolant showed a dose equivalent I-131 of 1.19 microcuries/cc. This exceeds the dose equivalent I-131 Technical Specification of less than 1.0 microcuries/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 microcuries/cc.

8712310213 871222 PDR ADOCK 05000280 S DCD NRC Form 386

POW 28-06-01 NIICl'*111Ja1A e e

  • U.I. NUCLEAII IIEOULATORY COMMISSION IM31 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION APPROVED 0MB NO. 3150--0104 EXPIRES: 8/31/1111 FACILITY NAMI 111 DOCKET NUMIEII 121 UII NUMHIICII PAGI 131 Surry Power Station, Unit 1 o I5 I o I o I o I 2 I 8 I o 8 I7 - n I ~ I n - n I n n I ., OF nl ':I TIXT f/1,,.. - * - - - - - N / t C FotmBA'1/ 1171 1.0 Description of the Event On November 26, 1987, at 0415 hours0.0048 days <br />0.115 hours <br />6.861772e-4 weeks <br />1.579075e-4 months <br />, following a Unit 1 shutdown for repairs to the secondary manway on

'C' Steam Generator, the specific activity sample of the reactor coolant showed a dose-equivalent I-131 level of 1.19 microcuries/cc. This exceeds the dose equivalent I-131 limit of 1.00 microcuries/cc specified in Technical Specification 3.i.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 10CFRlOO limits following a postulated Steam Generator Tube Rupture (SGTR). Since the dose-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.

Therefore, the health and safety of the public were not affected.

3.0 Cause The iodine spike was caused by a known, but not specifically located, fuel element defect in the.

reactor core. Post shutdown conditions errhanced the release of fission products, specifically I-131. This caused an increase in reac~or coolant specific activity.

4.0 Immediate Corrective Actions 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 microcuries/cc.

N"C FO .. M:IMA

  • U.S.GPO: 1118e-0-824-538/41111 11-131

POW 28-06-01 e e U.I. NUCLIAII IIIGULATOIIY COMMI.ION LICENSEE EVENT REPORT (LERI TEXT CONTINUATION A"IIOVEO OMI NO. 31IO-C104 lll1'111EI: I/JI/a PACILITY NAMI 111 DOC1t1T NUMIIII 121 LIii NUMIIII Ill PAGI 131 Surry Power Station, Unit 1 O l510IOIOl 1IRln n hlu II_.,. --//#IC --.c*,1117!

R 17 .... -n In nl 30F Oj 3 TIXT,,, _ -

Supplemental Information:

The following supplemental information required by Technical Specification 3.1.d.4 "Special Report" 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:

November 23, 1987 @ 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> 100% power.

November 24, 1987 @ 0800 hours0.00926 days <br />0.222 hours <br />0.00132 weeks <br />3.044e-4 months <br /> 100% power.

November 24, 1987 @ 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> 97% power.

November 25, 1987 @ 1405 hours0.0163 days <br />0.39 hours <br />0.00232 weeks <br />5.346025e-4 months <br /> 100% power.

November 25, 1987@ 2001 hours0.0232 days <br />0.556 hours <br />0.00331 weeks <br />7.613805e-4 months <br /> - started 150 mw/hr rarnpdown from 100% for repairs to 'C' Stearn Generator Secondary Manway.

November 26, 1987@ 0135 hours0.00156 days <br />0.0375 hours <br />2.232143e-4 weeks <br />5.13675e-5 months <br /> - Reactor Shutdown.

2. Fuel burnup by core region as of November 26, 1987.

Fuel Batch Burnup S2/8A 35147 MWD/MTU S1/8B 30665 MWD/MTU Sl/9A 33641 MWD/MTU Sl/9B 34137 MWD/MTU S2/9B 33746 MWD/MTU S2/10A 31204 MWD/MTU Sl/llA 14544 MWD/MTU Sl/llB 14116 MWD/MTU Cycle 9 Burnup: 12024 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:

November 26, 1987 @ 0105-Routine Sample: .0365 microcuries/cc November 26, 1987 @ 0415-Post Shutdown Sample: 1.19 microcuries/cc November 26, 1987 @ 0750-Post Shutdown Sample: 1.02 microcuries/cc November 26, 1987 @ 1120-Post Shutdown Sample: 0.82 microcuries/cc Event Duration: Approximately 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />.

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e VIRGINIA ELECTRIC AND POWER COMPANY Surry Power Station P. 0. Box 316 Surry, Virginia 23883 December 22, 1987 U.S. Nuclear Regulatory Commission Serial No.: 87-039 Docmnent Control Desk Docket No.: 50-280 016 Phillips Building Licensee No.: DPR-32 Washington, D.C. 20555 Gentlemen:

Pursuant to Surry Power Station Technical Specifications, Virginia Electric and Power Company hereby submits the following Special Report for Surry Unit 1.

REPORT NUMBER 87-034-00 This report has been 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

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