United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 84-42: Equipment Availability for Conditions During Outages Not Covered by Technical Specifications

                                                            SSINS No. 6835 
                                                            IN 84-42 

                                UNITED STATES
                        NUCLEAR REGULATORY COMMISSION
                    OFFICE OF INSPECTION AND ENFORCEMENT
                            WASHINGTON, DC 20555 

                                June 5, 1984

Information Notice No. 84-42:   EQUIPMENT AVAILABILITY FOR CONDITIONS 
                                   DURING OUTAGES NOT COVERED BY TECHNICAL 
                                   SPECIFICATIONS 

Addressees: 

All holders of a nuclear power plant operating license (OL) or construction 
permit (CP). 

Purpose: 

This information notice is provided to alert licensees to the importance of 
controlling equipment availability for conditions during outages not covered
by Technical Specifications. It is expected that recipients will review the 
information for applicability to their facilities and consider actions, if 
appropriate, to preclude similar problems occurring at their facilities. 
However, suggestions contained in this information notice do not constitute 
NRC requirements and, therefore, no specific action or written response is 
required. 

Description of Circumstances: 

On January 8, 1984, the Palisades Nuclear Plant experienced a complete loss 
of offsite and onsite ac power. The event was precipitated by the need to 
isolate a faulty switchyard breaker. To isolate the breaker, it was 
necessary to interrupt the offsite power supply to the plant. At the time of 
the event, Palisades was in a refueling outage with all fuel removed from 
the reactor and the no. 2 diesel generator (DG) inoperable. The service 
water pump powered from the no. 1 (operable) DG also was inoperable as a 
result of maintenance. 

When the shift supervisor interrupted the offsite power supply to the plant,
the operators did not realize cooling water to the operable DG was not 
available. The control room alarm indication, which should have warned the 
operators, was apparently masked by the large number of simultaneous alarms 
received when the offsite power was interrupted. Approximately 50 minutes 
later the DG overheated and was manually tripped. Once the DG was tripped, 
all station power was lost, with the exception of the station batteries and 
their associated dc and preferred ac buses. The loss of ac power caused a 
loss of plant communications, fire protection, security, and habitability 
systems as well as the fuel pool cooling system. (Compensatory measures were 
promptly taken upon loss of the normal security systems.) The loss of 
communications is considered the most serious consequence of this event. 
This loss of communications will be further addressed in a separate 
information  


8406050012 
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                                                            IN 84-42 
                                                            June 5, 1984 
                                                            Page 2 of 3 

notice (IN). The restoration of ac power was delayed as a result of an inop-
erable main transformer (out for maintenance) and a malfunction of one of 
the startup supply breakers. 

While operating procedures required two operable diesel generators,before 
removing offsite power, operating procedures did not specifically delineate 
equipment availability requirements for this defueled condition. The shift 
supervisor violated the procedure and proceeded with the evolution after 
evaluating fuel cooling. The fuel pool was known to heat up very slowly and 
to require days without active cooling before the high temperature alarm 
would be reached. The shift supervisor, however, failed to fully recognize 
the importance of the other support systems (e.g., communication, fire pro-
tection) to the *overall safety of the plant. The procedural requirements 
were reviewed as part of the evaluation of fuel cooling and it was 
determined their intent was to minimize risk to fuel integrity when the fuel 
was in the reactor vessel. 

Following the loss of onsite and offsite ac power, the Emergency Procedures 
were not implemented in a timely manner because the importance of the 
various support systems had not been recognized. 

The licensee initiated many corrective actions as a result of this event 
(see Palisades Licensee Event Report (LER) 84-001). Some of the more 
important corrective actions by the licensee include: 

1.   A review of the management control of equipment for plant conditions 
     not covered by the requirements of the Technical Specifications. The 
     review will specifically address electrical system requirements during 
     cold shutdown to ensure sufficient equipment remains available to 
     maintain the plant in a safe condition and to meet the commitments of 
     the Site Emergency, Security, and Fire Protection Plans. 

2.   Establishing minimum equipment availability for specific conditions not
     covered by the Technical Specifications. 

3.   Provide classroom training for all operators on the use and intent of 
     the Site Emergency Plan. 

4.   Integrate the use of the Site Emergency Plan into simulator training. 

5.   Discuss the need for strict adherence to operating procedures with all 
     operations personnel. 

NRC has previously identified concerns with operability of required 
equipment in IE IN 83-56, "Operability of Required Auxiliary Equipment," and 
IN 80-20, "Loss of Decay Heat Removal Capability at Davis-Besse Unit 1 While 
in a Refueling Mode." If you have any questions regarding this matter, 
please 

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                                                            IN 84-42 
                                                            June 5, 1984 
                                                            Page 3 of 3 

contact the Regional Administrator of the appropriate NRC Regional Office or
this office. 


                                   Edward L. Jordan, Director 
                                   Division of Emergency Preparedness 
                                        and Engineering Response 
                                   Office of Inspection and Enforcement 

Technical Contact:  H. Bailey, IE 
                    (301) 492-7078 

Attachment: 
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