ML19338D593

Special Rept 80-4:on 800623,unit Received Safety Injection Signal from High Steam Flow & lo-lo Tave Signal or Lo Steam Generator Pressure.Approx 540 Gallons Borated Water Injected Into RCS at 190 F.Originally Reported as 5,400 Gallons

ML19338D593
Person / Time
Site:	Sequoyah
Issue date:	09/17/1980
From:	TENNESSEE VALLEY AUTHORITY
To:
References
RO-80-4, NUDOCS 8009230524
Download: ML19338D593 (4)

Text

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f TENNESSEE VALLEY AUTHORITY CH ATTANCOGA. TENNESSEE 374ot 1750 Chestnut Street Tower II i

September 17, 1980 Mr. James P. O'Railly, Director U.S. Nuclear Regulatory I'-4 asion Office of Inspection and Enforcement Ragion II 101 Marietta Street, Suite 3100 Atlanta, Georgia 30303

Dear Mr. O'Reilly:

TENNESSEE VALLEY AUTHORITY - SEQUOYAH NUCLEAR PLANT UNIT 1 - DOCKET NO. 50-327 - PACILITY OPERATING LICENSE DP'R SPECIAL REPORT 804 The enclosed special report provides infor: nation concetning da e.aargency I

core cooling system injection to the reactor coolant system. ?ais report is submitted in accordance with Segacyah unit 1 Terknie=1 Specification 6.9.2 and 3.5.3.

Very truly yours, TENNESSEE VAILEY AUTHORITY J. R. Calhoun Director of Nuclaar Power Enclosure (3) cc (Enclosure):

I Director (3)

Office of Management Information an.1 Program Control U.S. Nuclear Regulato / Commission Washinoton, DC 20555 \\

Director (40)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Connaission Washington, DC 20555 Mr. Bill Lavallee Nuclear Safety Analysis Center Palo Alto, california 94303

$O Mr. W. T. Cottle, NRC Inspector, Sequoyah 3

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Special Report 80-4 Sequoyah Nuclear Plant Unit 1 ECCS INJECTION TO REACTOR COOLANT SYSTEM Plant Status Date: June 23, 1980 Mode 3 Reactor Pressure 1725 psig Reactor Temperature 538 F

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Event Description and Probable Consequences Unit 1 received a Safety Injection (SI) signal from High Steam flow and either Lo-Lo Tave signal or Lo Steam Generator pressure. Approximately 540 gallons of borated water was injected into the RCS at 190 F.

This event was originally reported as having injected 5400 gallons of borated water into the RCS. In reviewing the incident it has been de-termined that approximately 540 gallons of water was actually pumped into the RCS during the two-minute safety injection.

Sequoyah Technical Specification LCO 3.5.2 sequires that the current value of the usage factor be included in the Special Report if the usage factor exceeds 0.7.

Usage factors for the nozzles are not available at this time because the primary piping was designed to the USAS B31.1 Power Piping Code which does not require fatigue analysis.

However, IE Circular 78-05 states that Westinghouse informed Public Service Electric and Gas Company that 50 safety injections using 400F water would not result in excessive stress at the safety injec-tion nozzles on the Salem I Plant. Salem I is similar to Sequoyah.

Based en IE Circular 78-05, conversations with Westinghouse, and a preliminary evaluation, it is our opinion that the usage factor for the affected nozzles has rot exceeded 0.7.

I Cause Description and Lorrective Actions 0

The Reactor Coolant System Temperature fell below 541 F (Lo-Lo Tave) to 5380F. The operator opened all four MSIV's which brought in the Hi Steam flow signal.

The safety injection was terminated, two minutes af ter the SI signe.1 was activated, and the reactor coolant system was restored to pre-initiation conditio a.

Operations personnel have been cautioned to sre carefully observe plant conditions that could lead to a safety injection during abnormal plant operations.

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Special Report 80-4 Sequoyah Nuclear Plant Unit 1 ECCS INJECION TO REACOR COOLANT SYSTEM Plant Status Date: June 23, 1980 Mode 3 Reactor Pressure 1725 psig Reactor Temperature 538 F

~

Event Description and Probable Consequences Unit i received a Safety Injection (SI) signal from High Steam flow and either Lo-Lo Tave signal or lo Steam Generator pressure. Approximately 540 gallons of borated water was injected into the RCS at 190 F.

This event was originally reported as having injected 5400 gallons of borated water into the RCS. In reviewing the incident it has been de-termined that approximately 540 gallons of water was actually pumped into the RCS during the two-minute safety injection.

Sequoyah Technical Specification LCO 3.5.2 requires that the current value of the usage factor be included in the Special Report if the usage factor exceeds 0.7.

Usage factors for the nozzles are not available at this time because the primary piping was designed to the USAS B31.1 Power Piping Code which does not require fatigue analysis.

However, IE Circular 78-05 states that Westinghouse informed Public Service Electric and Cas Company that 50 safety injections using l

400F water would not result in excessive stress at the safety injec-tion nozzles on the Salem I Plant. Salem I is similar to Sequoyah.

Based on IE Circular 78-05, conversations with Westinghouse, and a preliminary evaluation, it is our opinion that the usage factor for the affected nozzles has not exceeded 0.7.

Cause Description and Corrective Actions The Reactor Coolant System Temperature fell below 5410F (Lo-Lo Tave) to 5380F. The operator opened all four MSIV's which brought in the Hi Steam flow signal.

The safe' ion was terminated, two minutes after the SI signal was activate., and the reactor coolant system was restored to pre-initiation conditions. Operations personnel have been cautioned to more carefully observe plant conditions that could lead to a safety injection during abnormal plant operations.

Special Report 80-4 Sequoyah Nuclear Plant Unit 1 ECCS INJECTION TO REACIOR COOLANT SYSTEM Plant Status Date: June 23, 1980 Mode 3 Reactor Pressure 1725 psig Reactor Temperature 538 F Evenc Description and Probable Consequences Unit i received a Safety Injection (SI) signal from High Steam flow and either Lo-Lo Tave signal or Lo Steam Generator pressure. Approximately 540 gallons of borated water was injected into the RCS at 190 F.

This event was originally reported as having injected 5400 gallons of borated water into the RCS. In reviewing the incident it has been de-termined that approximately 540 gallons of water was actually pumped into the RCS during the two-minute safety injection.

Sequoyah Technical Specification LCO 3.5.2 requires that the current value of the usage factor be included in the Special Report if the usage factor exceeds 0.7.

Usage factors for the nozzles are not available at this time because the primary piping was designed to the USAS B31.1 Power Piping Code which does not require fatigue analysis.

However, IE Circula: 78-05 states that Westinghouse informed Public Service Electric and Gas Company that 50 safety injections using 400F water would not result in excessive stress at the safety injec-tion nozzles on the Salem I Plant. Salem I is similar to Sequoyah.

Based on IE Circular 78-05, conversations with Westinghouse, and a preliminary evaluation, it is our opinion that the usage factor for the affected nozzles has not exceeded 0.7.

Cause Description and Corrective Actions 0

The Reactor Coolant System Temperature fell below 541 F (Lo-Lo Tave) to 5380F, The operator opened all four MSIV's which brought in the Hi Steam flow signal.

The safety injection was terminated, two minutes af ter the SI signal was activated, and the reactor coolant system was restored to pre-initiation conditions. Operations personnel have been cautioned to more carefully observe plant conditions that could lead to a cafety injection during abnormal plant operations.

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