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LER 94-007-01:on 940308,determined That Portions of EDG Fuel Oil Transfer Sys,Including Storage Tank T-10 & Associated Piping Not Tornado Protected.Caused by Partial Design Info. Design Basis Documents Will Be updated.W/940725 Ltr
	ML18059B120
Person / Time
Site:	Palisades
Issue date:	07/25/1994
From:	Roberts W, Rogers D; CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
	LER-94-007, LER-94-7, NUDOCS 9407280164
	Download: ML18059B120 (7)
	v • d • e

consumers Power David W. Rogers Plant Safety and Licensing Director POWERiNii lllllCHlliAN"S PROliRESS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway, Covert, Ml 49043 July 25, 1994 Nuclear Regulatory Commission Document Control Desk

Washing~on, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -

LICENSEE EVENT REPORT 94-007 EOG FUEL OIL SUPPLY DOES NOT MEET LICENSING BASIS - SUPPLEMENTAL REPORT . . .

Licensee Event Report (LER) 94-007-01, is attached. This supplemental report acknowledges the NRC's July 7, 1994 letter agreeing with our justification for continued operation until permanent repairs can be made to the fuel oil transfer system. This report also extends the completion date for mddiftcations to-protect the transfer pumps from a s~iche until July 31, 1994

as was previously described in our letter of June 30, 1994 which identified commitment delays.

This event was originally reported in accordance with 10CFR50.73(a)(2)(ii)(B) as a condition qutside the design basis. *

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Plant Safety and Licensing Director CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades Attachment

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9407280164 940725 PDR ADOCK 05000255 S PDR A CMS ENERGY COMPANY

NRC Form 366 (9*83) e U.S. NUCLEAR REGULATORY COMMISSION APPROVED OMB NO. 3160-0104 EXPIRES: 8/31 /86 LICENSEE EVENT REPORT (LERI FACILITY NAME Ill - DOCKET NUMBER (2) PAGE 131 Palisades Plant o I Io Io Io I I sI 5 2 5 1 I OF o. Ia TITLE 141 EDG FUEL OIL SUPPLY DOES NOT MEET LICENSING BASIS - SUPPLEMENTAL REPORT

- *. EVENT DATE 16) LER NUMBER 161 REPORT DATE 161 OTHER FACILITIES INVOLVED (8)

MONTH DAY YEAR YEAR

- SEQUENTIAL NUMBER Ii RE\1SION NUMBER MONTH DAY YEAR FACILITY NAMES N/A 0161010101 I ol3 ola 9 4 914 01011 0 I 1 011 215 914 N/A 0161010101 I THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR I: fCMt:k °""or more of me following/ 111 l OPERATING N MOOE 19) 20.402(b) 20.406(c) 60.73.loll2Hivl 73.71(b)

POWER LEVEL 110) o Io 10 20.4061*ll1Hil 20.4061*ll1lliil -- 60.36(c)(1) 60.361cll2l 60.731*ll2)(v) 60.731oll2llvii) 73.71(c)

OTHER (Specify in Abotroct

-=

20.4061*111 )(iii) x 60.731*ll2lli)

- 60.731oll2llviii)(A) below end in Text, 20.406(0)(1 )(iv) 20.4061*111 )(v) 60.731*ll2llii) 60.7 31*ll2lliii) - 60.731oll2llviiil1Bl 60.731*ll2llxl NRC Form 366A)

LICENSEE CONTACT FOR THIS LER 1121 NAME TELEPHONE NUMBER

,William L. Roberts, Staff Licensing Engineer :TA1c1°~ I1 I s I ~ I - I a I s I I 3 1 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 113)

MANUFAC* REPORTABLE MANUFAC- REPORTABLE

. : .*I CAUSE SYSTEM COMPONENT TUR ER TO NPROS

*

CAUSE SYSTEM COMPONENT TUR ER TO NPRDS*

I I I I I I I I I I I I I I .*.**********.*******.*.******** ,.

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I I I I I I I I .I I I I I I n

SUPPLEMENTAL REPORT EXPECTED 114) MONTH DAY YEAR ***************

EXPECTED YES. Vf yu, complete EXPECTED ~UBMISS/O~ DATE) . - .

lxl NO ..

SUBMISSION DATE 1161

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ABSTRACT Wmit to 1400 speces, i.e., eppro>cimetoly fifteen $ingltt-spece typewritten line~) 116)

On March 8, 1994 the plant was ii"! cold shutdown. During an evaluation of the emergency diesel generator (EDG) fuel oil supply system it was determined that portions of the emergency diesel generator fuel oil transfer system, including the storage tank, T-10 and associated piping, is not tornado protected. It was also established that this condition did not meet the origin.al General Design Criteria (GDC-2). It has also been determined that the storage tank and associated piping has not been maintained as safety related since plant construction and the diesel fuel oil transfer system is not fully protected from the effects of a design basis seiche as determined in .the Systematic_ Evaluation Program (SEP)_.

The cause of the event is incomplete design basis information. -. - . ,_

Corrective action for this event includes providing interim measurers to ensure a continuous diesel fuel oil supply is available to the EDGs in the event of a design basis event. Additional physical protection and procedures for a transfer of diesel fuel oil to the EDGs will be in place prior to plant startup.

NRC Form 366A U.S. NUCLEAR REGULATORY COMMISSION 19-831 APPROVED OMB N0.*3160-0104 EXPIRES: 8/31/86 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME 11 l DOCKET NUMBER 121 LER NUMBER 131 PAGE 141 SEQUENTIAL REVISION YEAR NUMBER NUMBER Palisades Plant 0 I 5 I0 I0 I0 I2 I5 I5 9 I4 - 0 I0 I7 - 0 I0 0 I2 OF 0 I6 EVENT DESCRIPTION On March 8, 1994 the plant was in cold shutdown. During an evaluation of the emergency.

diesel generator (EOG) [EK] fuel oil supply system [DC] it was determined that portions of the emergency diesel generator fuel oil transfer system, including the storage tank, T-10 [DC;TK] and associated piping, is not tornado protected. It was also established that this condition did not meet the original General Design Criteria (GDC-2). It has also been determined that the storage tank and associated* piping has not been maintained as safety related since plant construction and the diesel fuel oil transfer system is not fully protected from the effects of a design basis seiche as determined in the Systematic Evaluation Program (SEP).

A fully qualified diesel fuel oil transfer system has become more important as load changes to the emergency diesel generators have resulted in an increase in the fuel oil usage rate and thus a corresponding increase in the quantity of fuel that must be stored to meet design requirements.

Additionally, the increased fuel usage rate impacts the.need to replace the fuel oil in the diesel generators' day tanks in a shorter time frame.

Although the above situations exist, it is concluded that the current design is sufficient to ensure safe shutdown in the event of a design basis accident provided certain compensatory measures are taken. I ' .

These compensatory measures are*to increase the reliability of the EDGs in a tornado and in a flooding event resulting from a seich~. Consideration will be given to long term actions to improve the EOG fuel oil transfer system and to provide a fully qualified 7-day fuel oil supply.

CAUSE OF THE EVENT*

The cause of this event is incomplete design basis information.

ANALYSIS OF THE EVENT.

There are two emergency diesel generators at Palisades designed to provide a dependable onsite power source capable of starting and supplying the essential loads to safely shut down the .pJaot _

and maintain it safely shut down in all plant conditions. The generators have sufficient capacity to supply the minimum necessary engineered safeguards loads with only one generator operating.

NRC Form 366A U.S. NUCLEAR REGULATORY COMMISSION (9*831 APPROVED OMB NO. 3160*

0104 EXPIRES: 8131186 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME '(1 l DOCKET NUMBER 121 LER NUMBER 131 PAGE 14)

SEQUENTIAL REVISION YEAR NUMBER NUMBER Palisades Plant Each diesel generator is supplied fuel oil by its diesel belly tank, an adjacent day tank and a.

common transfer system. The transfer system consists of an underground fuel oil storage tank, T-10, a single supply line and two transfer pumps, P-18A and P-188. One of the two transfer pumps, P-18A, has automatic controls and is supplied power from a non-safety related but reliable power source. The other pump, P-188, has manual controls but is fed from a safety related power supply. Operator action is therefore required to start either pump following a loss of off-site power. A 7-day fuel oil supply for one EDG is provided by the storage and transfer system. The storage requirements are met by the combined capacities of the day tank and underground storage tank.

An additional diesel fuel oil storage tank (T-926) also exists. No credit has been taken in the*

licensing basis for T-926. Because of its rugged construction in a concrete encasement, tan~ T-926 has been judged (engineering judgement) as able to withstand the effects of a design basis tornado or tornado missile, seismic event, or seiche. The transfer piping from T-926 is, however, located in structures which would not withstand these events.

The Palisades licensing basis has always assumed some dependence on the ability to procure off site sources of fuel oil. The original FSAR and Technical Specifications bases both point to capability to provide refilling of the EOG day tanks from outside the diesel generator rooms. This dependence was also considered during the Systematic Evaluation Program in the NRC's evaluation of Topic Vll-3, dated December 31, 1981.

There has been ongoing evaluation of the EOG fuel *oil supply as follow-up to the NRC's EDSFI and as pc;irt of our Configuration Control Project. In 1993 concerns were raised in-house about our ability to provide a 7-day diesel fuel oil supply.* This question arose following a bounding worst case calculation which concluded that the diesel generator fuel oil consumption rate would result in consumption of the EOG belly and day tanks in 11. 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months versus 27. 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months assumed in the FSAR and Technical Specifications bases. The issue was resolved when analyses were performed which concluded that an on-site 7-day diesel fuel oil supply was available. The FSAR was revised to incorporate the 11.2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months .

The 11.2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months was recently proven to be overly conservative and incorrect. New test data from I a special test April 22, 1994 show that the fuel consumption rate is at or below the original I manufacturers data. 1-

NRC Form 366A U.S. NUCLEAR REGULATORY COMMISSION Ul-831 APPROVED OMB NO. 3160*

0104 EXPIRES: 8/31 /86 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME (1) . DOCKET NUMBER (21 LER NUMBER (31 PAGE (41 SEQUENTIAL REVISION YEAR NUMBER NUMBER Palisades Plant 0 I5 I0 I0 I0 I2 I5 I5 9 I4 - 0 I0 I7 - 0 I1 0 I4 OF 0 I6 .

IA seismic walk-down and an evaluation of the diesel fuel oil transfer system in conjunction with*

!other seismic evaluation (SOUG) walkdowns was conducted. The result of the walkdown and evaluation was that the transfer system from the T-10 tank was determined to be seismically qualified. The transfer system from the T-926 tank was evaluated a.nd judged to be inadequate due to threaded pipe fittings and because the piping is routed through structures that are not seismically qualified ...

Continuation of evaluation of the documentation related to the diesel fuel oil transfer system from the T-1 O storage tank to the EOG day tanks resulted in the recent determination that the tank was originally intended to be protected from tornado and tornado missile damage in accordance with the original GDC-2 requirements. During original construction the design, to include a concrete cover on T-10, was changed and the cover was not installed. Our evaluation has now determined that the tank and transfer system does not meet the original requirements. Further evaluation was conducted to compare the. design to the original General Design Criteria in an effort to identify all* other potential GDC issues related to the diesel fuel oil transfer system.

Other evidence was found that indicates the diesel fuel oil storage and transfer sy.stem from the T-1 O tank was originally meant to be safety related but it has never been treated as such.

The original criteria for flooding of the T-10 tank and transfer system appear to have been considered and met. During the Systematic Evaluation Program (SEP Topic 11-3.A, 11-3.B, and 11-3.C; NRC SER supplement received by letter dated October 7, 1982) in 1982 a new flood level, as a result of a seiche, was developed by the NRC. The new flood level which is the present licensing basis assumes a maximum monthly mean lake level of 582.6 feet and a *probable maximum-flood level of 593.5 feet. Since during the SEP the diesel. fuel oil transfer system was considered to be non-safety related, flooding of the transfer pumps was not reviewed in this issue evaluation. With this new flood level, consideration of the effects of the seiche have now been reconsidered. To fully qualify the diesel fuel oil transfer system from the effects of the licensing basis flood, the pumps need to be protected from the flooding effects of the seiche.

Safety Significa,nce To provide assurance that the treatment of the diesel fuel oil transfer system as non-safety related over the years has not affected the reliability of the system, an evaluation of the system material condition was conducted of the active and passive system components. This evaJl!atLQD. _

considered the available data including surveillance and operating procedures, maintenance, testing and operational information that would provide reliability information on the system .

components. No records of excavation of the underground components, as an indication of corrosion, were located, but no evidence of component deterioration was located either.

NRC Form 366A U.S. NUCLEAR REGULATORY COMMISSION (8-831 APPROVED OMB NO. 3160-0104 EXPIRES: 8/31 /86 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME (11 DOCKET NUMBER 121 LER NUMBER (31 PAGE (41 SEQUENTIAL REVISION YEAR NUMBER NUMBER Palisades Plant 0 5 0 0 0 2 5 5 9 4 -o 0 7 -o 0 5 OF. 0 6 The conclusion of the evaluation is that the diesel fuel oil transfer system is reliable and functional. Sufficient surveillance, maintenance and operational activities provide this assurance even though the system has not been maintained as safety related over the years.

It has been concluded that the current design is sufficient to ensure safe shutdown in a design basis accident provided certain compensatory measures are taken. The measures are to increase the reliability of the EOGs in a tornado and in a flooding event resulting from a seiche. The major action is to provide a manually connected transfer hose and air pump to transfer oil from the T-926 tank to the diesel generator day tanks. In the interim, until the diesel fuel oil transfer pumps are protected from the flooding effects of a seiche, this manual transfer capability will be available in the unlikely event of a tornado missile or seiche. Further longer term actions to improve .the EOG fuel oil transfer system will be required in order to provide a fully qua*

fuel oil supply. -<

The fuel oil transfer* system meets the Technical Specifications requirements for operable I equipment and fuel oil supply and is enhanced by the completed corrective actions. CPCo I, determined that operation of the diesel generator fuel supply with interim measures implemented I does not present an undue risk to the public health and safety. The interim measures are the I short term actions presented in this LER and were completed prior- to plant startup. I CORRECTIVE ACTIONS On May 23, 1994, Palisades submitted a justification for- continued operation (JCO) with the electric diesel generator fuel supply system using. temporarily installed equipment to meet GOC-2.

At the request of the NRC staff, supplementary information regarding the JCO was provided on June 3, 1994. The JCO is intended to be effective until modifications are complete which enable the EOG fuel supply system to meet the original Palisades licensing basis by having a permanently installed seven day fuel supply that complies with GOC-2. The modifications will be completed as soon as possible but no later than the end of the refueling outage following the 1995 -refueling outage.* On June 7, 1994, the NRC concluded that continued operation with the interim compensatory measures and commitments is acceptable until the permanent modifications are implemented.

Short Term Actions completed prior to plant start-up

Provide barriers around T-10 for routine protection from vehicles.

Provide procedures and equipment to transfer oil from T-926 directly to the diesel generator day tanks.

Provide a barrier at the T-926 connection to T-10.

Provide a memo to the plant staff defining the safety related aspects of the T-10 tank and the diesel fuel oil transfer system.

NRC Form 366A U.S. NUCLEAR REGULATORY COMMISSION (9-831 APPROVED OMB NO. 3160-0104 EXPIRES: 8/31 /86 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (31 PAGE (41 SEQUENTIAL REVISION YEAR NUMBER NUMBER Palisades Plant 0 I 5 I o. I 0 I 0 I 2 I 5 I 5 9 I4 - 0 I0 I7 - 0 I1 0 I6 OF 0 I6 Long Term Actions

Protect the fuel oil transfer pumps from potential flooding from a seiche. This action will be completed by July 31 ~ 1994.

Evaluate the system to determine the modifications required to upgrade it to a fully qualified 7-day diesel fuel oil supply.

Clarify the FSAR as to the licensing basis of the system by the next FSAR update.

Update design basis documents.

ML18059B120

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