ML18065A769

LER 96-008-00:on 960513,fire Door Not Maintained Open in Accordance W/Design Basis.Cause Under Investigation. Engineering Evaluation Performed & Revised Documents, Surveillance & Test procedures.W/960612 Ltr

ML18065A769
Person / Time
Site:	Palisades
Issue date:	06/12/1996
From:	Engle D, Smedley R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-96-008, LER-96-8, NUDOCS 9606180562
Download: ML18065A769 (5)

Text

consumers Power POWERING MICHIGAN'S PROGRESS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway, Covert, Ml 49043 June 12, 1996 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT INFORMATIONAL LICENSEE EVENT REPORT 96-008, FIRE DOOR NOT MAINTAINED OPEN IN.ACCORDANCE WITH DESIGN BASIS DOCUMENT Informational Licensee Event Report (LER)96-008 is attached. This event was originally reported by telephone to the NRC on May 13, 1996, as reportable in accordance with 10 CFR 50.72(b)(1 )(ii)(B) as a condition outside the plant design basis. We have since determined that the design basis document, which was referenced in the May 13, 1996 report, was incorrect. It incorrectly stated fire door 81 A had to remain in the open position to meet design requirements.

Fire door 81 A, which separates the two Mechanical Equipment Rooms (MER), was discovered in the closed position. The Design Basis Document (DBD) for the Control Room Heating, Ventilation and Air Conditioning System (HVAC) stated that the door had to remain open to assure that the two MERs remain pressurized at all times to prevent infiltration of outside air into the HVAC system and affect the habitability of the Control Room. The Control Room HVAC envelope includes the Control Room, Viewing Gallery, Technical Support Center and the two MERs. Upon further engineering evaluation, the Control Room HVAC System was determined to function as designed to maintain the Control Room HVAC envelope pressurized in accordance with the design basis, with fire door 81A in the open or closed position.

9606180562 960612 PDR ADOCK 05000255 S PDR A CMS ENERGY COMPANY

2

SUMMARY

OF COMMITMENTS This letter contains two new commitments as follows:

1. Perform an engineering evaluation and revise the affected documents to show door 81A may remain in the closed position.

2. Revise the surveillance test procedure to assure door 81 A will remain closed in the normal and emergency operating modes.

Richard W. Smedley Manager, Licensing CC Administrator, Region Ill, USNRC Project Manager, NRR, USNRC NRC ~esident Inspector - Palisades Attachment

NRC FORM 366 (4195)

U.S. NUCLEAR REGULATORY COMMISSION

• APPROVED BY OMB NO. 3160..0104 EXPIRES 4130/98 ESTIMATED BllUlEH PER RESPONSE TO COllPL Y Wini THIS IWIOATORY INFORMATION COU.ECT10N REQUEST: 50.0 HRS. REPORTED LESSONS LEARNED ARE INCORPORATED LICENSEE EVENT REPORT (LER) INTO lliE LICENSING PROCESS AHO FED BACK TO INDUSTRY. FORWARD COllllENTS

. REGARDING BURDEN ESTIMATE TO lliE INFORMATION AHO RECORDS llNIAGEllENT BRNICH (T-8 F33), U.S . ..ic:LEAR REGUIATORY COlllllSSION, WASHINGTON, DC :zo55S.

0001, AHO TO lliE PAPERWORK RECUCTION PROJECT (315Q.0104, OFFICE OF (See reverse for required number of digits/characters for each block) 11.<HAGEllENT NID BUOGET, WASHINGTON, DC 20503 FACILITY NAME (1) DOCKET NUMBER (2) Page (3)

PALISADES NUCLEAR PLANT 05000255 1of3 TITLE(4) INFORMATIONAL LICENSEE EVENT REPORT 96-008, FIRE DOOR NOT MAINTAINED OPEN IN ACCORDANCE WITH DESIGN BASIS EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

MONTH DAY YEAR YEAR I SEQUENTIAL NUMBER REVISION NUMBER MONTH DAY YEAR FACILITY NAME FACILITY NAME DOCKET NUMBER 05000 DOCKET NUMBER 05 13 96 96 - 008 - 00 06 12 96 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check one or more) (11)

MODE (9) N 20.2201(b) 20.2203(a)(2)(v) 50.73(a)(2)(1) 50. 73(a)(2)(iii)

POWER 20.2203(a)(1) 20.2203(a)(3)(1) 50. 73(a)(2)(ii) 50.73(a)(2)(x)

LEVEL (10) 100 20.2203(a)(2)(1) 20.2203(a)(3)(ii) 50.73(a)(2)(iii) 73.71 20.2203(a)(2)(ii) 20.2203(a)(4) 50. 73(a)(2)(iv) x OTHER 20.2203(a)(2)(iii) 50.36(c)(1) 50.73(a)(2)(v) Specify in Abstract below or 20.2203(a)(2)(ivl 50.36(c)(2l 50. 73(a)(2)(viil in NRC Form 366A LICENSEE CONTACT FOR THIS LER (12)

NAME DALE E. ENGLE, LICENSING ENGINEER TELEPHONE NUMBER (Include Area Code)

(616) 764-2848 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TONPRDS TONPRDS SUPPLEMENTAL REPORT EXPECTED (14) MONTH DAY YEAR x I YES If yes, COMPLETE EXPECTED COMPLETION DATE

. I NO EXPECTED SUBMISSION DATE (15) 09 01 96 ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)

On May 13, 1996, at 1445, with the plant operating at 100% power, during the review of the Design Basis Document (DBD) for the Control Room Heating, Ventilation and Air Conditioning (HVAC) System, it was discovered that door 81A, which separates the two ventilation system Mechanical Equipment Rooms (MERs), was in the closed position, contrary to the DBD. The DBD incorrectly stated that the door had to remain open to assure that the two MERs remain pressurized at all times to prevent the infiltration of outside air into the Control Room HVAC System and thus affect the habitability of the Control Room. On May 15, 1996, a new fusible link was installed to return door 81A to an open position in accordance with the DBD. We have since determined that the design basis document which was referenced and resulted in the May 13, 1996 report was incorrect. It incorrectly stated fire door 81A had to remain in the open position to meet the design requirements.

NRC FORM 366a 4195

• LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION

• U.S. NUCLEAR REGULATORY COMMISSION I

FACILITY NAME 11 l DOCKET12l LER NUMBER 16l PAGE 13)

• ----.-~** ...........--'

YEAR SEQUENTIAL REVISION NUMBER NUMBER 2 OF 3 PALISADES NUCLEAR PLANT 05000255 96 008 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

EVENT DESCRIPTION In 1984, a new Heating, Ventilation and Air Conditioning (HVAC) System was installed to meet the requirements of NUREG 0737. This system provides conditioned air to the Control Room, Viewing Gallery, Technical Support Center and the two Mechanical Equipment Rooms (MERs). The HVAC System consists of.redundant trains of HVAC equipment with each train-located in a separate MER The MERs are in adjacent rooms and share common ducts to the Control Room and other areas. Door 81A separates the two MERs and the Design Basis Document (DBD) stated the door had to act as both a fire barrier (closed position) and as a ventilation flow path (open position) during normal operation of the HVAC System. The DBD stated the door had to remain open to assure that the two MERs remained pressurized at all times (except during a fire) to prevent the infiltration of outside air into the Control Room HVAC System and, thus, affect the habitability of the Control Room. During the installation of the Control Room HVAC, door 81A was installed with a fusible link which allowed the door to provide both functions.

On May 13, 1996, at 1445, with the plant operating at 100% power, during the review of the DBD, it was discovered that door 81A, which separates the* ventilation system MERs, was in the closed position, contrary to the statements of the DBD. The fusible link which is required to hold the door in the open position had been removed.

SAFETY SIGNIFICANCE The Control Room HVAC System performs two safety-related functions: 1) maintains Control Room temperature suitable for occupancy and operabili_ty of safety-related equipment, and 2) maintains positive pressure in the Control Room envelope in emergency conditions to ensure a habitable environment. During the period from 1984 to 1990, surveillance testing was performed which only documented the Control Room maintained positive presswe. Pressure in the MERs was not measured.

Due to system configuration, the two MERs need to remain pressurized to maintain the Control Room pressure. Actually, we have now determined that the two MERs are pressurized even when door 81A is either open or closed. Therefore, even though the pressure was measured only in the Control Room and not in the MERs, a loss of pressure retaining capability in either MER would have affected the Control Room pressure and would have caused a failure of the surveillance test.

In 1990, the surveillance test procedure was revised to have door 81 A open during performance of the test. This was done to ensure the maximum volume was included in the test boundary, thus providing the greatest challenge to the operating HVAC train. The test was also revised to include measuring and documenting pressure in the combined MERs (with door 81A open), as well as in the Control Room, while the HVAC System is in the emergency operating mode.

NRC FORM 366a 4195 LICENSEE EVENT REPORT (LER)

• • U.S. NUCLEAR REGULATORY COMMISSION TEXT CONTINUATION I

. - FACli-.ITY NAME 11 \ OOCKET121 LER NUMBER 16\ PAGE 13\

YEAR SEQUENTIAL REVISION NUMBER NUMBER 3 OF 3 PALISADES NUCLEAR PLANT 05000255 96 008 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

On Friday, May 17, 1996, data was collected and evaluated which demonstrated positive pressure is maintained in the two MERs and the Control Room when door 81A is closed. Therefore, because positive pressure was maintained with the door 81A closed and previously performed surveillance testing.would have indicated a lack of pressure retaining capabilities in the system envelope if positive pressure had not been maintained, we have determined that this event has no safety significance.

CAUSE OF THE EVENT The cause of this event is still under investigation and will be provided in a supplement to this Licensee Event Rep9rt.

• CORRECTIVE ACTIONS The engineering process and organizational changes that have occurred since 1984 would have

.prevented the root.causes of this condition. However, the following corrective actions will be performed.*

1. Perform an engineering evaluation and revise the affected documents to show door 81A may remain in the closed position. '

2. Revise the surveillance test procedure to assure door 81A will remain closed in the normal and emergency operating modes.