Information Notice 1994-19, Emergency Diesel Gemerator Vulnerability to Failure from Cold Fuel Oil

Emergency Diesel Gemerator Vulnerability to Failure from Cold Fuel Oil

ML031060595
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	03/16/1994
From:	Grimes B Office of Nuclear Reactor Regulation
To:
References
IN-94-019, NUDOCS 9403100310
Download: ML031060595 (10)

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATORY

WASHINGTON, D.C. 20555 March 16, 1994 NRC INFORMATION NOTICE 94-19: EMERGENCY DIESEL GENERATOR VULNERABILITY TO

FAILURE FROM COLD FUEL OIL

Addressees

All holders of operating licenses or construction permits for nuclear power

reactors.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information

notice to alert addressees to a safety problem that could lead to the common

mode failure of all emergency diesel generator units as a result of

temperature-related changes in the fuel oil. It is expected that recipients

will review the information for applicability to their facilities and consider

actions, as appropriate, to ayoid similar problems. However, suggestions

contained in this information notice are not NRC requirements; therefore, no

specific action or written response is required.

Description of Circumstances

Vermont Yankee

During the electrical distribution safety functional inspection conducted from

July 6 to August 7, 1992 (Inspection Report 50-271/92-81), the NRC team found

that the Vermont Yankee emergency diesel generators may be vulnerable to

excessive viscosity problems and the formation of wax crystals in cold fuel.

The team expressed concern about the operability of the emergency diesel

generators during those times when the actual outdoor temperature falls below

the minimum temperature used in the procurement specification for the pour

point of the oil. The pour point characteristic of the fuel oil is usually

slightly lower than the cloud point characteristic. The cloud point is

defined as the temperature at which a cloud of wax crystals appears in the

fuel oil and begins to precipitate. When such a cloud appears, the capability

to transfer the fuel oil from the storage tank to the emergency diesel

generator engine cylinders might be degraded because of wax crystals clogging

fuel oil filters and plating out on the walls of the fuel oil piping. This

could result in the common mode failure of both emergency diesel generator

units.

The licensee final safety analysis report specified a design outdoor

temperature of -11VC [120F]. The licensee technical specifications require - /Z

compliance with American Society for Testing and Materials (ASTM) Standard

D-975-68. This standard stipulates that for cold weather operation, the pour

point of the emergency diesel generator fuel oil should be 6'C [l0F] below

9403100310 pl 5t Mv° q 1oK

iJ<94-19 March 16, 1994 the ambient temperature at which the engine is to be operated except where

fuel oil heating facilities are provided. The inspection team observed no

heat tracing on the fuel oil storage tank, which is located outside, and that

the heat tracing on the fuel oil transfer piping was not energized with a

safety-related source of power. Therefore, on the basis of the design outdoor

temperature, the pour point of the fuel oil should be no higher than -17C

[20F]. The licensee procured fuel oil with a pour point of -18C [O'F].

Consequently, the inspection team agreed that on the basis of the design

outdoor temperature, the requirements of the licensee fuel oil procurement

specification met those of the ASTM standard and hence those of the technical

specification.

Even so, the inspection team questioned whether the licensee can assure the

operability of the fuel oil transfer system and hence the emergency diesel

generator because the licensee final safety analysis report noted that the

minimum recorded outdoor temperature during a nine year observation period was

-36-C [-33F].

Point Beach

During the electrical distribution safety functional inspection from March 12 to April 6, 1990 (Inspection Report 50-266/90-201), the NRC team found a

similar potential vulnerability of emergency diesel generators to excessive

viscosity problems in cold fuel oil. A licensee calculation to determine the

ability of the fuel oil to drain by gravity from the outside storage tanks to

the day tanks indicated that under very low temperatures (-9°C [150F]), no

drainage would occur because the ambient temperature would be less than the

cloud point of the fuel oil in the storage tanks and the above-ground piping.

Moreover, the calculation showed that the minimum average temperature at which

fuel could drain to one day tank was only -180C [ODF]. The licensee tested

the drainage for about 15 minutes in warm weather, but this did not

demonstrate flow during extremely cold weather. The licensee now uses a fuel

oil blend (No. 1 and No. 2) that corresponds to a cloud point of -240C

[-12'F). In addition, in very cold weather, fuel oil in the bulk tanks is

recirculated and the temperature is monitored. In extreme conditions, tank

trucks are kept on site and parked in a heated warehouse as necessary.

Discussion

Manufacturers of emergency diesel generators normally specify the type of fuel

oil to be used in their engines and refer either to ASTM Standard D-975, Federal Specification VV-F-800, or their own detailed specifications. In

either case, the heating, burning, physical, and chemical characteristics of

the fuel are established to ensure proper operation of the emergency diesel

generator units. These fuel oil specifications provide specific values for

cloud point, pour point, and viscosity. Both the pour point and viscosity

affect the capability of the fuel oil system to transfer fuel oil from a

storage tank to the emergency diesel generator engine cylinders.

Unless licensees establish that stored emergency diesel generator fuel oil has

the proper cloud, pour and viscosity characteristics, the common mode failure

94-19 March 16, 1994 of all emergency diesel generator units could occur. This is particularly

true when fuel oil storage tanks and fuel transfer piping are outside and

above ground where they are subject to large changes in ambient temperature.

Emergency diesel generator fuel oil that is procured to specifications that do

not properly establish the lowest expected temperature (cloud and pour point)

requirements is especially susceptible. In conducting the routine 1-hour

monthly surveillance runs or outage surveillance tests, the licensee may not

operate the emergency diesel generator long enough to observe the effect of

the cold fuel oil. Most of the fuel oil used during these tests will be from

day tanks, which are at a higher temperature because they are located in the

emergency diesel generator rooms. In contrast, an accident may require

continuous operation of the emergency diesel generator for several days. The

warmer fuel in the day tanks would be depleted. The emergency diesel

generator would then be required to perform on fuel oil at a temperature that

approximates the outside temperature. Improperly specified (procured)

emergency diesel generator fuel oil for which the lowest expected use

temperature is not taken into account could lead to a common mode failure of

all the emergency diesel generator units.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Gene Lazarowitz, RI

(215) 337-5392 Vern Hodge, NRR

(301) 504-1861 Attachment:

List of Recently Issued NRC Information Notices

AttaL_&ent

IN 94-19 March 16, 1994 Page 1 of I

LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

94-18 Accuracy of Motor- 03/16/94 All holders of OLs or CPs

Operated Valve Diag- for nuclear power reactors.

nostic Equipment

(Responses to Sup- plement 5 to Generic

Letter 89-10)

94-17 Strontium-90 Eye Appli- 03/11/94 All U.S. Nuclear Regulatory

cators: Submission of Commission Medical Use

Quality Management Plan Licensees.

(QMP), Calibration, and

Use

94-16 Recent Incidents Resulting 03/03/94 All U.S. Nuclear Regulatory

in Offsite Contamination Commission material and fuel

cycle licensees.

94-15 Radiation Exposures during 03/02/94 All U.S. Nuclear Regulatory

an Event Involving a Fixed Commission licensees author- Nuclear Gauge ized to possess, use, manu- facture, or distribute

industrial nuclear gauges.

94-14 Failure to Implement 02/24/94 All holders of OLs or CPs

Requirements for Biennial for nuclear power and non- Medical Examinations and power reactors and all

Notification to the NRC licensed reactor operators

of Changes in Licensed and senior reactor

Operator Medical Conditions operators.

92-36, Intersystem LOCA 02/22/94 All holders of OLs or CPs

Supp. I Outside Containment for nuclear power reactors.

Unanticipated and Un- 02/22/94 All holders of OLs or CPs

intended Movement of for nuclear power reactors.

Fuel Assemblies and

Other Components due to

Improper Operation of

Refueling Equipment

OL - Operating License

CP - Construction Permit

IN 94-19 V.JiMarch 16, 1994 of all emergency diesel generator units could occur. This is particularly

true when fuel oil storage tanks and fuel transfer piping are outside and

above ground where they are subject to large changes in ambient temperature.

Emergency diesel generator fuel oil that is procured to specifications that do

not properly establish the lowest expected temperature (cloud and pour point)

requirements is especially susceptible. In conducting the routine 1-hour

monthly surveillance runs or outage surveillance tests, the licensee may not

operate the emergency diesel generator long enough to observe the effect of

the cold fuel oil. Most of the fuel oil used during these tests will be from

day tanks, which are at a higher temperature because they are located in the

emergency diesel generator rooms. In contrast, an accident may require

continuous operation of the emergency diesel generator for several days. The

warmer fuel in the day tanks would be depleted. The emergency diesel

generator would then be required to perform on fuel oil at a temperature that

approximates the outside temperature. Improperly specified (procured)

emergency diesel generator fuel oil for which the lowest expected use

temperature is not taken into account could lead to a common mode failure of

all the emergency diesel generator units.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager. Odginal

Brian K. Grimes, Director Brian K.Grimes

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Gene Lazarowitz, RI

(215) 337-5392 Vern Hodge, NRR

(301) 504-1861 Attachment:

List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCES

This information notice was reviewed and commented upon by the Point Beach

Project Manager on 01/24/94.

OFFICE *OGCB:DORS:NRR *EB:DRS:RI *EB:DRS:RI *EB:DRS:RI *RPB:ADM

NAME CvHodge GLazarowitz WHRuland JDurr Tech Ed

DATE 1_05/11/93 j05/11/93 105/11/93 05/11/93 J12/09/92 EMCB:DE:NRR* EMCB:DE:NRR* l C/EMCB:DE:NRR AD:DE:NRR AC/OGCB:DORS:NRR

KIParczewski RAHermann JStrosnider* MWHodges* AJKugler*

02 /15/! 4 02/15/ 94 02/18/94 02/18/94 02/23/94 LI

Du;enN

t6/I/ /94-2 Document Name : 94-19. IN

V -L IN 94-XX

January xx, 1994 requirements is especially susceptible. In conducting the routine 1-hour

monthly surveillance runs or outage surveillance tests, the licensee may not

operate the emergency diesel generator long enough to observe the effect of

the cold fuel oil. Most of the fuel oil used during these tests will be from

the day tanks, which are at the warmer emergency diesel generator room

temperature. In contrast, an accident may require continuous operation of the

emergency diesel generator for several days. The warmer fuel in the day tanks

would be depleted. The emergency diesel generator would then be required to

perform on fuel oil at a temperature that approximates the outside

temperature. For plants in the northern and Midwestern parts of the country, this could be about -30°C. Improperly specified (procured) emergency diesel

generator fuel oil for which the lowest expected use temperature is not taken

into account may lead to a common mode failure of all the emergency diesel

generator units.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Gene Lazarowitz, RI

(215) 337-5392 Vern Hodge, NRR

(301) 504-1861 Attachment: List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCES

This information notice was reviewed and commented upon by the Point Beach

Project Manager on 01/24/94.

OFFICE *OGCB:DORS:NRR *EB:DRS:RI *EB:DRS:RI *EB:DRS:RI *RPB:ADM

NAME CVHodge GLazarowitz WHRuland JDurr Tech Ed

DATE 05/11/93 ,05/11/93 105/11/93 05/11/93 12/09/92 J

. .,

C/OGCB:DORS:NRR ID/DORS:NRR I

GHMarcus BKGrimes

01/ /94 01/ /94 Document Name: EMDIEZEL. IN FO - ScO1O, I P

i

V-~ IN 94-XX

February xx, 1994 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Gene Lazarowitz, RI

(215) 337-5392 Vern Hodge, NRR

(301) 504-1861 Attachment:

List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCES

This information notice was reviewed and commented upon by the Point Beach

Project Manager on 01/24/94.

OFFICE *OGCB:DORS:NRR *EB:DRS:RI *EB:DRS:RI *EB:DRS:RI *RPB:ADM

NAME CVHodge GLazarowitz WHRuland L krr Tech Ed

DATE 05/11/93 05/11/93 05/11/93 11/93 12/O9/92 EMCB:D NRR EMCB:DER A R *AC/OGCB:DORS:NRR

KIP ewski RAHer=n ni der s _ oJKugler

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02/l7/ 02/)/Z94 02/ g/94 02/_ 94 02/___94 D/DORS:NRR --d-2

. '371-12-41 BKGrimeQ-

02/ /94 Document Name: EDG-COLD.INF

IN 94-XX

February xx, 1994 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Gene Lazarowitz, RI

(215) 337-5392 Vern Hodge, NRR

(301) 504-1861 Attachment: List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCES

This information notice was reviewed and commented upon by the Point Beach

Prolect Manaser on 01/24/94.

OFFICE

NAME

DATE

• OGCB:DORS:NRR

CVHodge

05/11/93 I *EB:DRS:RI

GLazarowitz

,05/11/93

• EB:DRS:RI

WHRuland

,05/11/93

• EB:DRS:RI

JDurr

J05/11/93

• RPB:ADM

Tech Ed

12/09/92_J

- - 1 AC/OGCB:DORS:NRR D/DORS:NRR

AJKugler VI BKGrimes T

02/3/94 02/ /94 Document Name: EDG-COLD.INF

IN 93-XX

May xx, 1993 This Information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Gene Lazarowitz, RI

(215) 337-5392 Vern Hodge, NRR

(301) 504-1861 Attachment: List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCES

OFFICE *OGCB:DORS:NRR *EB:DRS:RI *EB:DRS:RI *EB:DRS:RI *RPB:ADM

NAME CVHodge GLazarowitz WHRuland JDurr Tech Ed

DATE 05/11/93

.

105/11/93

.1

05/11/93 ,05/11/93 112/09/92 C/OGCB:DORS:NRR D/DORS:NRR

GHMarcus BKGrimes p)ie

1,I wour743

01/ /93 01/ /93 Document Name: EMDIESEL.IN

IN 93-XX

January xx, 1993 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Gene Lazarowitz, RI

(215) 337-5392 Vern Hodge, NRR

(301) 504-1861 Attachment: List of Recently Issued NRC Information Notices

Document Name: EMDIESEL.IN

• SEE PREVIOUS CONCURRENCES

D/DORS:NRR C/OGCB:DORS:NRR

BKGrimes GHMarcus

01/ /93 01/ /93 OGCB:DOdS:NRR EB:DRS:RI EB:dRS.R EB:DRS-R 1 *RPB:ADM

CVHodge GLazarowitz WHRuland JDurr e- wo, 5 TechEd

03'/I1 /93 037/i/93/ 03-/11 /93 Of/li/93 v 12/09/92