05000285/LER-1976-019, Suppl 1 to LER 76-19/03L:on 761001,five of 10 Valve Setpoints Drifted from Tech Spec Tolerance of Plus or Minus 1%.Caused by Change in Environ Condition.Valves Will Be Inspected During Refueling Outage

Suppl 1 to LER 76-19/03L:on 761001,five of 10 Valve Setpoints Drifted from Tech Spec Tolerance of Plus or Minus 1%.Caused by Change in Environ Condition.Valves Will Be Inspected During Refueling Outage

ML20087K036
Person / Time
Site:	Fort Calhoun
Issue date:	10/14/1976
From:	William Jones, Mehaffey R, Moyers S OMAHA PUBLIC POWER DISTRICT
To:	Howard E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20087K039	List: 05000285/LER-1976-019, Suppl 1 to LER 76-19/03L:on 761001,five of 10 Valve Setpoints Drifted from Tech Spec Tolerance of Plus or Minus 1%.Caused by Change in Environ Condition.Valves Will Be Inspected During Refueling Outage
References
FC-304-76, LER-76-19-03L, NUDOCS 8403230237
Download: ML20087K036 (5)

LER-2076-019, Suppl 1 to LER 76-19/03L:on 761001,five of 10 Valve Setpoints Drifted from Tech Spec Tolerance of Plus or Minus 1%.Caused by Change in Environ Condition.Valves Will Be Inspected During Refueling Outage

Event date:
Report date:
2852076019R00 - NRC Website

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Q LICENSEE EVENT RE@T 50_285/76-19 supplement No. 1 CONTHOL ULOCK:l l l l l l l (PLEA 9E PRINT ALL REQUIRED INFORMATION) 1 6 A E LCINSE NUM0fR vE TV E

@] l n I el F1 cl al il 7 Ob I o I o l-lo Io Io Io I o 1-10 lo l lh11 1111Ill Io13I 14 15 25 20 30 31 32 CAftGOHV T 00Cuti NUMUER (VENT DATE REPOnT DATE

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b6 l U69 y60 b l5 lo l-l0 l2l815l l110l0 l1 l 7 l 6l 01 68 69 74 l1 l 0 l 1l h l 7l 6l 75 80 EVENT DESCRIPTION

@ lDuring unit shutdown for refuelinc main steam safety valves were checked for relief l 7 UD 80

@E lnressure. Five of the ten valvec' cetpoints had drifted from Technical Specification l 7 11 9 80 h ltolernnee of plua or minun one percent. The valves will be inspected during the l 7 u9 e0 3E l refueling outace and their operation evaluated. (LER 50-285/76-19 Supplement No. 1) l 7 11 9 60 8I 7 UD I mest 80 1( E CODE COMPONENT CODE GUI ER M f U R VOLATON

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7 00 to 11 lV l A lL l V l El XI 12 -

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44 47 48 CAUSE DESCRIPTION DD l Valve relief prensure drifted due to possible cha' ige in environmental condition from l 7 ft 9 00 ll lthe settin6 temperature. Engineering Evaluation / Assistance Request Number 76 h9 has 7 n9 -

l e0 ll lbeen written to investigate the problem.

l FACILifY METHOD OF STATUS  % POWER OTHER STATUS DrSCOVERY DISCOVERY DEECRIPTON 7 8 9

@ 10 l0l0l0l l NA l W l Relief Pressure Test l 12 13 44 45 46 80 ACimiY CoditNT

• RELEASED AMOUNT OF ACTMTV H [2] OF RELEASE l NA lyz_J l l NA LOCATON OF RELEASE l

7 6 9 10 11 44 45 80 PERSONNEL EXPOSURES -

NUMDER TYPE DESCRIPTON DE l0 l o1 ol ( ZJ l nA l 7 . 8, 9 11 12 13 . .u 80 PERSONNEL INJUR ES .

NUMDfA DESCRIPT ON 810101 ol l NA . .

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/189 11 12 .; .

80 OFFSITE CONSEQUENCES ':

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~7 89 80 LOSS OR DAMAGE TO FACILITY Tver otSCnPTON

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80 PUDLICITY ,

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@ l NA 9403230237 761014 PDR ADOCK 05000285 l 7 8s a PDR 80 ADDITIONAL FACTORS 'J' '

@ l See Attachments 1, 2 and 3.' l 7 0U 30 l

E1 7.cU i 00 m S. M. Moyern/R. F. Me hn f re y . 402-h26-h011 .

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LER 50-285/76-19 Supplement No. 1

• Page Two A'IfACIDENT NO.1 Safety Analynis .

Technical Specification Section 2.1.6(3) requires eight of ten safety valves to be operable with the lift settings between 1000 psia and 1050 psia with a tolerance of j; 1.0% of the nominal nameplate setpoint.

The as found settings showed nine of ten safety valves to be operable with lift settings between 1000 psia and 1050 psia. However, five safety valves vere found to have drifted more than the j; 1.0% of nominal nameplate, as tabulated below:

. Safety Valve Setpoint As Found MS-275 1050 psia 1042

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FE-276 10h0 psia 1065 .

MS-277 1025 psia 10k0 MS-278 1015 psia 1020 MS-279 1050 psia 1048 ,

- M3-280 1040 psia 1038

. MS-281 1025 psia 1040 .

NS-282 1015 psia 1013

_ MS-291 1000 psia 1022 MS-292 , 1000 psia 1028

. The basis for th safety analysis is that the valve relief capacity be greater than 4.7 x 10g/b/hr to prevent overpressurization of the steam system at. loss of load conditions from rated power condition of 1h20 MWT although -

5 of 10 safety valves drifted greater than j; 1.0%, 9 safety valves were available to provide the required flow between 1000 psia and 1050 psia.

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(^; O v U LER 50-285/76-19 .

Supplement flo.1 Page Three ATTACIIME:IT NO. 2 Corrective Action The safety valve drift was found during unit :nutdown for refueling. The valves will be inspected durin6 the outage and vill be reset prior to unit power operation. In addition, Engineering Evaluation / Assistance Request Number 76-49 has been written to further investigate the problem.

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j LER 50-285/76-19 Supplement No. 1 .-

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ATTACH!ENT NO. 3 I

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i j This is the second failure of the main s' team safety valves - the first i-failure was reported in LER 50-285/76-19 i

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Omaha Public Power District ..~~

1023 HANNEY a OMAHA. NEDRASNA 68102 8 TELEPHONE S36 4000 AREA CODE 402 October 20, 1976 FC-304-76  % Jf I?icii

,//-3.d&p6 u,s, Mr. E. Morris Howard U. S. Nuclear Regulatory Commission

$5 Won %

Region IV c4 @ /.

611 IWan Plaza Drive - ,/ ,

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gj Suite 1000 ~ ~ '

Arlington, TX 76012

Reference:

Fort Calhoun Station Unit No. 1 Docket No. 50-285 In accordance with the Fort Calhoun Station's Technical Specifica-tions, the Omaha Public Power District, as holder of facility operating license DPR 40, submits three copies of the following licensee event supplement report for 50-285/76-19 to satisfy the requirements of Regula-tory Guide 1.16.

Sincerely, fl *(i[b W.C.fJones Section Manager Operations WCJ/WDD:rge Enclosure .

cc: Director, Office of Management Information and Program Control U. S. Nuclear Regulatory Commission Washington, DC 20555 (3)

Director, Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission -

9 Washington, DC 20555 (30)

Mr. L. C. Shalla SARC Chairman PRC Chairman '

Fort Calhoun File (2)