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Information Notice No. 94-13, Supplement 1: Unanticipated and Unintended Movement of Fuel

Assemblies and Other Components due to Improper Operation of Refueling Equipment

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555

June 28, 1994

NRC INFORMATION NOTICE 94-13, SUPPLEMENT 1: UNANTICIPATED AND UNINTENDED

 MOVEMENT OF FUEL ASSEMBLIES AND

 OTHER COMPONENTS DUE TO IMPROPER

 OPERATION OF REFUELING EQUIPMENT

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 supplement to alert addressees to an event involving unauthorized

movement of a defective spent fuel rod. It is expected that recipients will

review the information for applicability to their facilities and consider

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

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

specific action or written response is required.

Background

The NRC issued Information Notice (IN) 94-13, "Unanticipated and Unintended

Movement of Fuel Assemblies and Other Components Due to Improper Operation of

Refueling Equipment," to alert addressees to problems that could result from

inadequate oversight of refueling operations and inadequate performance on the

part of refueling personnel. IN 94-13 described various refueling events that

occurred at Vermont Yankee, Peach Bottom, Susquehanna, and Nine Mile Point.

These events demonstrate the importance of proper controls over, and operation

of, refueling equipment during use. A recent event at the Waterford Steam

Electric Station (Waterford) demonstrates the potential for fuel damage or

personnel hazards which could result from fuel-handling equipment that is not

properly stored and not secured from unauthorized use.

Description of Circumstances

On February 18, 1994, the Waterford plant was operating at 100-percent power

when a senior reactor operator found an unknown object hanging from the

fuel-handling machine in the fuel-handling building. Health physics

technicians measured radiation levels in the spent fuel pool area and found

them to be normal. Licensee personnel remotely secured the object with vise

grips and determined that underwater radiation levels were .2 to .7 Sv/hr

[20 to 70 R/hr] at 15 centimeters [6 inches] from the object. A Combustion

Engineering employee identified the object as a fuel rod encapsulation tube.

No visual damage was apparent on the tube. The licensee posted a security

guard in the spent fuel pool area and reported the event to the NRC.

9406220075. IN 94-13,

Supplement 1 June 28,

1994 Page 2 of 3

The licensee reviewed fuel storage records and determined that the tube

contained a defective fuel rod that had been removed from an irradiated fuel

assembly several years earlier. At that time, the tube had been placed in a

center guide tube in a grid cage stored in the spent fuel racks. The licensee

reviewed computer access records for the fuel-handling area and interviewed

relevant personnel about the event. Personnel who may have had access to the

fuel-handling machine completed questionnaires regarding the event. The

licensee determined that the refueling director had used the fuel-handling

machine the day before the object was discovered and had parked the

fuel-handling machine at a location directly over the fuel rod encapsulation

tube. However, the refueling director had not used the hoist and was not sure

that he would have noticed if the encapsulation tube was hanging from the

hoist at the time he used the machine. Surveillance records indicated that

the fuel rod encapsulation tube must have become attached to the fuel-handling

tool sometime between February 11 and 18, 1994.

Design drawings of the cap of the fuel rod encapsulation tube showed that the

outer diameter of the cap was about equal to the inner diameter of the end of

the fuel-handling tool. Apparently, the cap had become bound in the

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fuel-handling tool when the hoist was lowered to the top of the spent fuel

rack and, when the hoist was raised, the tube was completely removed from the

grid cage.

Although contractors had performed the fuel-handling operations for previous

refueling outages, Waterford personnel were scheduled to perform the fuel

handling for the March 1994 refueling outage. The licensee speculated that

one of the people assigned to fuel-handling activities for the March outage

may have inadvertently lifted the encapsulation tube while practicing the use

of the hoist. Personnel were required to notify health physics staff before

accessing the refueling machine; however, health physics records showed that

no one had made such a notification during this time. No keys or special

knowledge was needed to access the controls of the fuel-handling machine.

Electrical power could be obtained by closing two electrical breakers and

pushing one switch that were located on the machine. The licensee questioned

several employees, but no one admitted to unauthorized use of the

fuel-handling machine.

As an interim corrective action, the licensee deenergized the computer that

controls the fuel-handling machine by opening a breaker in a locked power

control center. The licensee planned to (1) develop a means to prevent the

fuel rod encapsulation tube from being inadvertently lifted by the

fuel-handling tool, (2) add a precaution to the operating procedure warning

operators not to lower the fuel-handling tool over the storage location, and

(3) add hoist manipulations to the lesson plans for proficiency training.

Discussion

Procedures governing the use of equipment for handling fuel and core

components may not prevent unauthorized or unintended operation of that

equipment. Precautions such as locking out breakers that energize the

fuel-handling equipment and the placement of placards in highly visible areas

declaring that unauthorized operation of fuel-handling equipment is forbidden

. IN 94-13, Supplement

1 June 28, 1994

Page 3 of 3

may help ensure that the equipment is not used without proper authorization.

Additionally, storing the fuel-handling machine in an area where accidental

movement of the hoist or grapple will not impact stored fuel or other

components may contribute to the prevention of inadvertent fuel movement or

damage. Management attention and oversight of the operation of fuel and core

component handling equipment is important to ensure that fuel and core

components are protected from damage or unauthorized movement and that plant

personnel are protected from unnecessary exposure to radiation.

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

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

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

/s/'d by AEChaffee

 Brian K. Grimes, Director

 Division of Operating Reactor Support

 Office of Nuclear Reactor Regulation

Technical contact: Dale A. Powers, RIV

 (817) 860-8195

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