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, 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, 05000000, Zimmer, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant, Skagit, Marble Hill
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:

room cooling

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

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

the

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

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

failure resulting from interaction with a non-safety system.

the diesel

The potential for this type of design problem may not be limitedIEtoInformation

room HVAC. Previous pneumatic problems have been discussed in

Pneu- Notices 86-50, "Inadequate Testing to Detect Failures of Safety-Related

"Excessive Pneumatic

matic Components or Systems," June 18, 1986 and 86-51, Leakage in the Automatic Depressurization System," June 18, 1986. Some effects

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

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

Room Cooling," November 19, 1985.

notice.

No specific action or written response is required by this information

Regional

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

Administrator of the appropriate regional office or this office.

Edward L. Jordan, Director

Division of Emergency Preparedness

and Engineering Response

Office of Inspection and Enforcement

Jim Stewart, IE

(301) 492-9061 Attachment: List of Recently Issued IE Information Notices

• See Previous Concurrences

01/ /Z87

• DEPER:IE *DEPER:IE *PSB: IE DMk JERosenthal

JCStewart AWDromerick DGable RLBaer

01/14/87 01/15/87 01/15/87 O1/.9./87 O1rZ3/87 ,,./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 Degraded Motor Leads in 2/4/87 All power reactor

Limitorque CD Motor facilities holding

Operators an OL or CP

87-07 Quality Control of Onsite 2/3/87 All power reactor

Dewatering/Solidification facilities holding

Operations by Outside an OL or CP

Contractors

87-06 Loss of Suction to Low- 1/30/87 All power reactor

Pressure Service Water facilities holding

System Pumps Resulting From an OL or CP

Loss of Siphon

87-05 Miswiring in a Westinghouse 2/2/87 All Westinghouse

Rod Control System power reactor

facilities holding

an OL or CP

87-04 Diesel Generator Fails 1/16/87 All power reactor

Test Because of Degraded facilities holding

Fuel an OL or CP

87-03 Segregation of Hazardous 1/15/87 All NRC licensees

87-02 Inadequate Seismic Quali- 1/15/87 All power reactor

fication of Diaphragm facilities holding

Valves by Mathematical an OL or CP

Modeling and Analysis

87-01 RHR Valve Misalignment 1/6/87 All PWR facilities

Causes Degradation of holding an OL or CP

ECCS in PWRs86-110 Anomalous Behavior of 12/31/86 All BWR facilities

Recirculation Loop Flow holding an OL or CP

in Jet Pump BWR Plants86-109 Diaphragm Failure In Scram 12/29/86 All BWR facilities

Outlet Valve Causing Rod holding an OL or CP

Insertion

OL = Operating License

CP = Construction Permit

IN 87-XX

January, 1987 Discussion:

cooling

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

review of

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

room HVAC requirements is completed, the licensee will either remove

mode

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

failure due to interaction with a non-safety system.

diesel

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

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

Pneu- Notices 86-50, "Inadequate Testing to Detect Failures of Safety-Related

matic Components or Systems", June 18, 1986 and 86-51, "Excessive Pneumatic

effects

Leakage in the Automatic Depressurization System", June 18, 1986. Some85-89, of loss of HVAC on electronics was discussed in IE Information Notice

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

Room Cooling", November 19, 1985.

notice.

No specific action or written response is required by this informationRegional

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

Administrator of the appropriate regional office or this office.

Edward L. Jordan, Director

Division of Emergency Preparedness

and Engineering Response

Office of Inspection and Enforcement

Jim Stewart, IE

(301) 492-9061 Attachment: List of Recently Issued IE Information Notices

D:DEPER:IE

ELJordan

01/ /87 c5 DEPER: IE PSB:IE DEPER:IE DEPER:IE DD:DEPER:IE

- JCStewart A Omerick DGabltt RLBaer JERosenthal SASchwartz

01/{N+/87 01/,/Q87 014q' /87 01/ /87 01/ /87 01/ /87