Information Notice 1987-09, Emergency Diesel Generator Room Cooling Design Deficiency

Emergency Diesel Generator Room Cooling Design Deficiency

ML031140530
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, 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, 05000000, Zimmer, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant, Skagit, Marble Hill, Crane
Issue date:	02/05/1987
From:	Jordan E NRC/IE
To:
References
IN-87-009, NUDOCS 8702060413
Download: ML031140530 (4)

SSINS No.: 6835 IN 87-09

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF INSPECTION AND ENFORCEMENT

WASHINGTON, D.C.

20555

February 5, 1987

ZE INFORMATION NOTICE NO. 87-09:

EMERGENCY DIESEL GENERATOR ROOM COOLING

DESIGN DEFICIENCY

Addressees

All nuclear power reactor facilities holding an operating license or a con- struction permit.

Purpose

This notice is to alert recipients of a potentially significant problem involv- ing degradation of emergency diesel generators (EDGs) following and caused by a

loss of offsite power (LOOP).

It is expected that recipients will review this

information for applicability to their facilities and consider actions, if

appropriate, to preclude a similar problem occurring at their facilities.

However, suggestions contained in this information notice do not constitute NRC

requirements; therefore, no specific action or written response is required.

Description of Circumstances

On December 24, 1986, the Carolina Power and Light Company determined that a

reportable condition existed at the two Brunswick Steam Electric Plants in

which a loss of offsite power could cause a common-mode loss of all four EDGs.

Using probabilistic risk assessment methodology during a review of the EDGs in

November 1986, the licensee discovered that the EDG room cooling air supply

would isolate during a LOOP.

At Brunswick, the outside air for EDG room cooling is drawn through two intakes

with a duct from each intake plenum to each of the four EDG rooms. This air is

for room ventilation only; the combustion air for the diesel engine is supplied

separately.

Each of the eight ducts has a pneumatically operated damper and

two fusible link fire dampers. The fire dampers were retrofit items.

The

original air-operated damper was designed by United Engineers and Contractors

Inc. to fail close upon loss of non-safety instrument air pressure. This air

supply is provided by an air compressor that is powered by the non-safety

balance of plant electrical supply and is not provided with standby ac or dc

power.

Should a LOOP occur, the non-safety instrument air pressure would

decrease and allow the air-operated dampers to close.

The temperature of the

EDG room would increase, depending on the ambient temperature and heat from the

diesel engine.

The qualified EDG control panel temperature of 104OF could be

exceeded, which might cause degradation and failure of the electrical and

electronic components in the control panels. This in turn might disable the

EDG when it is needed to mitigate the LOOP.

IN 87-XX

January, 1987 Discussion:

The licensee has locked the air-operated damper open to permit EDG room cooling

regardless of the non-safety instrument air status. After a review of the EDG

room HVAC requirements is completed, the licensee will either remove the

air-operated dampers or modify them to eliminate the potential for common mode

failure resulting from interaction with a non-safety system.

The potential for this type of design problem may not be limited to the diesel

room HVAC. Previous pneumatic problems have been discussed in IE Information

Notices 86-50, "Inadequate Testing to Detect Failures of Safety-Related Pneu- matic Components or Systems," June 18, 1986 and 86-51, "Excessive Pneumatic

Leakage in the Automatic Depressurization System," June 18, 1986. Some effects

of loss of HVAC on electronics was discussed in IE Information Notice 85-89,

"Potential Loss of Solid-State Instrumentation Following Failure of Control

Room Cooling," November 19, 1985.

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the Regional

Administrator of the appropriate regional office or this office.

Edward L. Jordan, Director

Division of Emergency Preparedness

and Engineering Response

Jim Stewart, IE

(301) 492-9061 Attachment:

List of Recently Issued IE Information Notices

• See Previous Concurrences

• DEPER:IE

JCStewart

01/14/87

• DEPER:IE

AWDromerick

01/15/87

• PSB: IE

DGable

01/15/87 DMk

RLBaer

O1/.9./87 JERosenthal

O1rZ3/87

01/

/Z87

,,./8~c

Attachment 1

IN 87-09

February 5, 1987

LIST OF RECENTLY ISSUED

IE INFORMATION NOTICES

Information

Date of

Notice No.

Subject

Issue

Issued to

87-08

87-07

87-06

87-05

87-04

87-03

87-02

Degraded Motor Leads in

Limitorque CD Motor

Operators

Quality Control of Onsite

Dewatering/Solidification

Operations by Outside

Contractors

Loss of Suction to Low-

Pressure Service Water

System Pumps Resulting From

Loss of Siphon

Miswiring in a Westinghouse

Rod Control System

Diesel Generator Fails

Test Because of Degraded

Fuel

Segregation of Hazardous

Inadequate Seismic Quali- fication of Diaphragm

Valves by Mathematical

Modeling and Analysis

RHR Valve Misalignment

Causes Degradation of

ECCS in PWRs

Anomalous Behavior of

Recirculation Loop Flow

in Jet Pump BWR Plants

Diaphragm Failure In Scram

Outlet Valve Causing Rod

Insertion

2/4/87

2/3/87

1/30/87

2/2/87

1/16/87

1/15/87

1/15/87

1/6/87

12/31/86

12/29/86

All power reactor

facilities holding

an OL or CP

All power reactor

facilities holding

an OL or CP

All power reactor

facilities holding

an OL or CP

All Westinghouse

power reactor

facilities holding

an OL or CP

All power reactor

facilities holding

an OL or CP

All NRC licensees

All power reactor

facilities holding

an OL or CP

All PWR facilities

holding an OL or CP

87-01

86-110

86-109 All BWR

holding

All BWR

holding

facilities

an OL or CP

facilities

an OL or CP

OL = Operating License

CP = Construction Permit

IN 87-XX

January, 1987 Discussion:

The licensee has locked the air operated damper open to permit EDG room cooling

regardless of the non-safety instrument air status. After a review of the EDG

room HVAC requirements is completed, the licensee will either remove the

air-operated dampers or modify them to eliminate the potential for common mode

failure due to interaction with a non-safety system.

The potential for this type of design problem may not be limited to the diesel

room HYAC.

Previous pneumatic problems have been discussed in IE Information

Notices 86-50, "Inadequate Testing to Detect Failures of Safety-Related Pneu- matic Components or Systems", June 18, 1986 and 86-51, "Excessive Pneumatic

Leakage in the Automatic Depressurization System", June 18, 1986. Some effects

of loss of HVAC on electronics was discussed in IE Information Notice 85-89,

"Potential Loss of Solid-State Instrumentation Following Failure of Control

Room Cooling", November 19, 1985.

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the Regional

Administrator of the appropriate regional office or this office.

Edward L. Jordan, Director

Division of Emergency Preparedness

and Engineering Response

Jim Stewart, IE

(301) 492-9061 Attachment:

List of Recently Issued IE Information Notices

c5 DEPER: IE

- JCStewart

01/{N+/87 A Omerick

01/,/Q87 PSB:IE

DGabltt

014q' /87 DEPER:IE

RLBaer

01/ /87 DEPER:IE

JERosenthal

01/ /87 D:DEPER:IE

ELJordan

01/

/87 DD:DEPER:IE

SASchwartz

01/ /87