Report to Congress on Abnormal Occurrences Fiscal Year 1997 Dissemination of Information

NUCLEAR REGULATORY COMMISSION

Report to Congress on Abnormal Occurrences Fiscal Year 1997

Dissemination of Information

Section 208 of the Energy Reorganization Act of 1974 (Pub. L. 93-

438) identifies an abnormal occurrence (AO) as an unscheduled incident

or event that the Nuclear Regulatory Commission (NRC) determines to be

significant from the standpoint of public health or safety. The Federal

Reports Elimination and Sunset Act of 1995 (Pub. L. 104-66) requires

that AOs be reported to Congress on an annual basis. During fiscal-year

1997, six events that occurred at facilities licensed or otherwise

regulated by the NRC and the Agreement States were determined to be

AOs. These events are discussed below. As required by Section 208, the

discussion for each event includes the date and place, the nature and

probable consequences, the cause or causes, and the action taken to

prevent recurrence. Each event is also being described in NUREG-0090,

Vol. 20, ``Report to Congress on Abnormal Occurrences, Fiscal Year

1997.'' This report will be available at NRC's Public Document Room,

2120 L Street N.W. (Lower Level), Washington, D.C., about three weeks

after the publication date of this Federal Register Notice.

97-1 Loss of Two of Three High Pressure Injection Pumps at Oconee

Nuclear Station Unit 3

One of the AO reporting criteria notes that a major deficiency in

design, construction, control, or operation having significant safety

implications requiring immediate remedial action can be considered an

AO.

Date and Place--May 3, 1997; Oconee Unit 3, a pressurized water

nuclear reactor plant designed by Babcock and Wilcox Company, operated

by the Duke Energy Corporation (formerly known as Duke Power Company),

and located about 8 miles north of Clemson, South Carolina.

Nature and Probable Consequences--On May 3, 1997, the Oconee Unit 3

reactor was shut down and the reactor coolant system (RCS) was being

cooled down for inspection of the high pressure injection (HPI)

discharge piping. The need for the inspection resulted from RCS leakage

from a weld crack in the HPI makeup piping on Unit 2. Reactor pressure

was approximately 270 psig, RCS temperature was approximately 205 deg.

F, one reactor coolant pump (RCP) was running, and the Low Pressure

Injection System was being used to cool down the RCS. Makeup water to

the RCS to compensate for the temperature decrease was being supplied

from the letdown storage tank (LDST) by one of the three HPI pumps.

Makeup to the LDST consisted of periodic batch additions as needed.

These plant conditions were below the point where the technical

specifications required that the HPI system must be operable; that is,

required to mitigate a small-break loss-of-coolant accident.

Plant cool-down evolutions appeared to be normal until the ``B''

HPI pump started to cavitate and makeup flow to the reactor coolant

system was lost. A RCP seal water (which is also supplied by the HPI

pump) low-flow signal automatically started the ``A'' HPI pump.

However, it also began to cavitate. (The third HPI pump is not designed

to automatically start on this signal and remained in the standby

condition.) The operators stopped both pumps and began troubleshooting

the problem. A Notification of Unusual Event was declared when it was

recognized that the pumps would be inoperable past the shift that was

on duty. Unit 3 pressure and temperature were stabilized and there was

no immediate concern that conditions would worsen.

Later investigations revealed that the potential for a more serious

situation existed if there had been a small break loss-of-coolant

accident, which is the design basis for the HPI system, prior to this

event. If such an accident had occurred, all three of the HPI pumps

would have automatically started and become inoperable very quickly. In

addition, the pumps may have become air bound and unavailable when the

pump suction was transferred to the Borated Water Storage Tank to

inject into the RCS. This would have significantly complicated recovery

from the accident, but would have been within the Emergency Operating

Procedure guidance and training provided to the operators. It would,

however, increase the probability of core damage. The length of time

that Unit 3 was in this degraded status could not be accurately

determined, but the condition may have existed since start-up in March

1997, when plant conditions required that the HPI system be operable.

Cause or Causes--Loss of the HPI pumps occurred when all of the

water was inadvertently pumped from the LDST because of faulty level

indication. The erroneous level indication was caused by the loss of

approximately one-half of the water in the level detector reference leg

because of a slight leak in the instrument fitting. This loss of the

reference leg water caused the tank level instrument to indicate a

water level higher than the actual level, a condition that may have

existed since February 1997, the last time the reference leg was

verified to be full. It also caused the loss of the low-level alarm. As

a result of these conditions, the operators did not provide makeup

water to the tank when it was needed, resulting in the HPI pump

continuing to run until the tank was empty. The LDST level detection

system consists of two level instruments connected to a common

reference leg. Thus, the condition affected both level detectors

equally.

In addition, the control room operators did not properly monitor

and detect the inaccurate LDST level indications. They did not notice

that for a short period of time the indicated level stopped decreasing

and continuously showed the tank to be approximately half-full at the

same time water was being pumped from the tank.

Actions Taken to Prevent Recurrence

Licensee--Corrective actions included (1) the addition of a second

reference leg to the LDST to provide separate level indications, (2)

enhanced operator training and procedures, and (3) the performance of

an HPI System Reliability Study that is to be completed by December 31,

1997.

[[Page 25881]]

NRC--Escalated enforcement, which incorporated this issue, resulted

in the determination that a Severity Level II violation existed, and

the licensee was assessed a $330,000 civil penalty. Information Notice

97-38, ``Level-Sensing System Initiates Common-Mode Failure of High-

Pressure-Injection Pumps,'' was issued on June 24, 1997, to alert other

licensees to this event.

This event is closed for the purpose of this report.

* * * * *

Other NRC Licensees--(Industrial Radiographers, Medical

Institutions, Industrial Users, etc.)

97-2 Overexposure of a Worker at Mallinckrodt, Inc., in Maryland

Heights, Missouri

One of the AO criteria notes that any unintended radiation exposure

to an adult (any individual 18 years of age or older) resulting in an

annual shallow-dose equivalent to the skin or extremities of 2500 mSv

(250 rem) or more will be considered for reporting as an AO.

Date and Place--May 14-15, 1997; Mallinckrodt, Inc.; Maryland

Heights, Missouri.

Nature and Probable Consequences--On May 14, 1997, an employee was

removing radioactive waste from the hot cell where rhenium-186 (Re-186)

was used. The employee was performing this task manually, using gloves,

instead of remotely. When he left the area, he attempted to perform a

personal contamination survey but the survey meter immediately went off

the scale. He assumed that the high count rate was due to background

radiation from an adjacent radioactive material transport cart and,

subsequently, forgot to resurvey himself in a low background area

before he left the facility that evening. Upon arrival at work the next

day, he was told that his urine sample, which he had submitted before

going home the previous night, indicated iodine-131 (I-131) radiation

contamination and that he was restricted from working with radioactive

material. At that time, he performed a personal contamination survey

and detected significant levels of contamination on his left thumb

which subsequently was identified as Re-186. The I-131 contamination

level did not exceed the AO criteria for exposure to radiation from

licensed material.

The licensee estimates that the individual received a shallow-dose

equivalent of 6090 millisievert (609 rem) to an area of about 0.75

square centimeters (0.12 square inches) on the palm side of the thumb

of his left hand. Lower levels of contamination were found on the back

of his right hand and fingers. On May 15, 1997, the employee had

undergone decontamination to the extent that only approximately 4

percent of the activity remained.

The licensee surveyed the offsite locations where the employee had

been after leaving work on May 14, 1997. Low levels of Re-186

contamination were found on three locations inside the employee's

vehicle and on various items in the bathroom and kitchen of his home.

The employee's vehicle and home were decontaminated. The employee was

examined by a physician who identified no immediate health effects.

However, according to a report from an NRC consultant, a small

possibility exists for skin cancer to develop in the exposed area of

the thumb.

Cause or Causes--The cause of the event was a procedural deficiency

in handling waste from the Re-186 hot cell. Normally, radioactive waste

in other hot cells at the facility was handled with remote tools.

However, in this case, procedural controls did not require remote

handling of the waste. Once the employee completed the work, poor

radiation work practices were exhibited as he cross-contaminated his

hands when he removed his gloves. In addition, the worker did not

investigate the detection of high count rates during his first attempt

to perform a contamination survey.

Actions Taken to Prevent Recurrence

Licensee--The staff was instructed on the importance of conducting

proper personal contamination surveys and the proper use of protective

clothing. The use of Re-186 was suspended until improvements to

existing waste disposal procedures could be evaluated and implemented.

Plans were made (1) to compile all existing contamination protection

procedures into one contamination protection procedure, (2) to evaluate

the use of a portal type monitoring system, and (3) to post personal-

monitoring reminder signs at all laboratory exits.

NRC--NRC conducted a special safety inspection, proposed a $55,000

civil penalty on December 17, 1997, and the licensee paid the civil

penalty on January 20, 1998.

This event is closed for the purpose of this report.

* * * * *

Agreement State Licensees

AS 97-1 Multiple Transuranic Overexposures to a Worker at Isotope

Products Laboratories in Burbank, California

One of the AO criteria notes that any unintended radiation exposure

to an adult (any individual 18 years of age or older) resulting in an

annual total effective dose equivalent (TEDE) of 250 millisievert (mSv)

(25 rem) or more; or an annual sum of the deep dose equivalent (DDE)

(external dose) and committed dose equivalent (CDE) (intake of

radioactive material) to any individual organ or tissue other than the

lens of the eye, bone marrow, and the gonads of 2500 mSv (250 rem) or

more will be considered for reporting as an AO. In addition, another AO

criterion states that a serious deficiency in management or procedural

controls in major areas will be considered for reporting as an AO.

Date and Place--Between January 1 and December 31, 1995; Isotope

Products Laboratories; Burbank, California.

Nature and Probable Consequences--A radiochemist was assigned to

make transuranic and other types of sources. The transuranics utilized

included the isotopes of plutonium-238 (Pu-238), Pu-239, Pu-240,

americium-241 (Am-241), and curium-244 (Cm-244). During January 1995,

while making a Cm-244 source, it was discovered that the exhaust fan of

the fume hood where the source was being fabricated was not working. An

analysis of room air samples confirmed the loss of Cm-244 into the

working area.

Bioassay results disclosed that the fecal and urine samples

provided by the radiochemist contained Cm-244 and Am-241. The licensee

hired dosimetry and radiation protection consultants as directed by the

State Agency. Careful analysis of the bioassay data by these

consultants, which included dose summation and retrospective time

correction for various intakes, suggested that during 1995 the

radiochemist received a TEDE of 383.20 mSv (38.32 rem) and a CDE of

6900 mSv (690 rem) to the bone surfaces. The specific exposures were as

follows: (1) committed effective dose equivalent (CEDE) of 271.8 mSv

(27.18 rem) from Cm-244, (2) CEDE of 80 mSv (8 rem) from Am-241, (3)

CEDE of 4.4 mSv (0.44 rem) from Pu-238, Pu-239, and Pu-240, and (4) DDE

of 27.0 mSv (2.70 rem) from external radiation.

The State Agency discovered this incident during a routine

inspection on December 5, 1995, and was initially reported to NRC in

January 1996. During

[[Page 25882]]

a follow-up inspection, the State Agency learned that another Cm-244

incident took place and was significant. The State Agency also learned

of other exposure incidents that indicated the licensee had a deficient

contamination control program, an inability to conduct internal dose

assessments, and inadequate management oversight. The State provided

additional information on these events to NRC in 1997.

Cause or Causes--The licensee's radiation protection program was

inadequate and lacked important elements needed to ensure the radiation

safety of its workers. Some of these inadequacies were the lack of (1)

work permits, (2) glove boxes for certain types of work, and (3)

radiation procedural controls.

Actions Taken To Prevent Recurrence

Licensee--After the licensee's consultants conducted their review

and comprehensive audit of the existing radiation protection program,

they made recommendations to ensure future compliance with the license

and regulations. The licensee hired a competent radiation safety

officer, and the radiochemist was assigned duties that did not involve

the handling or processing of radioactive materials.

State Agency--The State Agency completed its investigation and is

committed to closely tracking the licensee's radiation protection

program to ensure continued compliance.

This event is closed for the purpose of this report.

* * * * *

AS 97-2 Overexposure of a Radiographer and an Untrained Technician at

Wolf Creek Mine in Walker County, Alabama

One of the AO criteria notes that any unintended radiation exposure

to an adult (any individual 18 years of age or older) resulting in an

annual total effective dose equivalent (TEDE) of 250 millisievert (mSv)

(25 rem) or more; or an annual sum of the deep dose equivalent (DDE)

(external dose) and committed dose equivalent (CDE) (intake of

radioactive material) to any individual organ or tissue other than the

lens of the eye, bone marrow, and the gonads of 2500 mSv (250 rem) or

more will be considered for reporting as an AO. In addition, another AO

criterion states that a serious deficiency in management or procedural

controls in major areas will be considered for reporting as an AO.

Date and Place--July 1, 1996; Wolf Creek Mine, Walker County,

Alabama.

Nature and Probable Consequences--A radiographer, employed by

Certified Testing and Inspection of Cottondale, Alabama, and a

technician, employed by Ultron, Inc., of Mt. Vernon, Illinois, were

performing industrial radiography at the Wolf Creek Mine in Walker

County, Alabama, when they became so distracted by problems with

excessively exposed film that they forgot they had an exposure in

progress and entered the high radiation area without making a survey

and changed the film with the source in the unshielded exposed

position. The radiographer had received prior radiation safety

training, however, the technician, an employee of Ultron, Inc., had not

received prior radiation safety training. The radiography film and the

device used to support the source and the film during exposures were

being supplied to the radiographer by Ultron, Inc.

Consequently, both individuals received unintended radiation

exposure. The State Agency estimated that the radiographer received a

dose of 530 millisievert (mSv) (53 rem) to his head and 48 mSv (4.8

rem) to the center of his body and the Ultron, Inc., technician

received a dose of 110 mSv (11 rem) to his head and 28 mSv (2.8 rem) to

the center of his body. Neither individual reported any acute radiation

symptoms.

The radiography film supplied by Ultron, Inc., had faster and

different exposure characteristics than the film usually used by

Certified Testing and thus was being overexposed during processing in

the darkroom. The darkroom, which was supplied by Certified Testing,

utilized a homemade ``safe light,'' which had been made a safe light by

the application of red spray paint. The radiographer did not realize

beforehand that the light would not be ``safe'' for the film supplied

by Ultron, Inc.

Cause or Causes--The radiographer entered a designated high

radiation area with his alarm ratemeter turned off and without

following his normal practice of cranking in the source and surveying

the guide tube and camera. The radiographer interpreted the silence

from the alarm ratemeter as an indication of safe conditions.

Unfortunately, when turned off, the alarm ratemeter gives the same

indication as it does when indicating safe conditions. In addition, the

radiographer did not utilize a collimator to reduce the exposure to

himself and the Ultron, Inc., technician.

Actions Taken To Prevent Recurrence

Licensee--The licensee stated that the radiographer did not develop

any symptom of acute radiation exposure and that its personnel were

reinstructed in the importance of performing surveys and using a

collimator. The licensee committed to the State Agency to verify the

training of all technicians, including those of the company that hires

the licensee to perform radiography.

State Agency--The State Agency cited the Licensee for the following

four violations: (1) excessive exposure to a radiation worker, (2)

excessive exposure to a member of the public (the Ultron, Inc.,

technician representative), (3) failure to prevent unauthorized entry

into the High Radiation Area, and (4) failure to exercise ALARA by

using a collimator. A civil penalty was considered but not imposed. The

State Agency recommended that both individuals contact the State and

seek medical attention if any symptoms of acute exposure should appear.

This event is closed for the purpose of this report.

* * * * *

AS 97-3 Radiopharmaceutical Misadministration at Mad River Community

Hospital in Arcata, California

One of the AO criteria states that a medical misadministration that

results in a dose that is equal to or greater than 10 gray (Gy) (1000

rad) to any organ (other than a major portion of the bone marrow, to

the lens of the eye, or to the gonads) and represents a dose or dosage

that is at least 50 percent greater than that prescribed in a written

directive will be considered for reporting as an AO.

Date and Place--February 28, 1996; Mad River Community Hospital;

Arcata, California. The State initially reported this event to NRC in

December 1996.

Nature and Probable Consequences--A patient was prescribed a dosage

of 3.7 megabecquerel (MBq) (0.1 millicurie [mCi]) of iodine-131 (I-131)

for a thyroid scan and uptake procedure. However, the patient was

administered a dosage of 262.7 MBq (7.1 mCi) of I-131. As a result, the

patient's thyroid received a dose of about 9100 centigray (cGy) (9100

rad), instead of the prescribed dose of 130 cGy (130 rad).

The licensee stated that such a dose may induce a hypothyroid state

requiring the patient to take thyroid hormone.

Cause or Causes--The wrong dosage was administered on the

assumption that the patient was prescribed a whole body thyroid scan

for a cancer metastatic disease evaluation.

Actions Taken To Prevent Recurrence

Licensee--Procedures for scheduling a whole body scan for thyroid

cancer metastases were revised to include a detailed patient

preparation and history.

[[Page 25883]]

The revised procedures required that the approving radiologist sign the

I-131 administration policy before ordering a radiopharmaceutical. In

addition, the nuclear medicine technologist attended a continuing

education program at San Francisco General Hospital, which included a

segment on the effects of studies involving therapy dosages.

State Agency--The State Agency conducted numerous follow-up

inspections to ensure that the licensee's actions taken to prevent

recurrence had been implemented.

This event is closed for the purpose of this report.

* * * * *

AS 97-4 Radiopharmaceutical Misadministration at Tuomey Regional

Medical Center in Sumter, South Carolina

One of the AO criteria notes that a medical misadministration that

results in a dose that is equal to or greater than 10 gray (Gy) (1000

rad) to any organ (other than a major portion of the bone marrow, to

the lens of the eye, or to the gonads) and represents a dose or dosage

that is at least 50 percent greater than that prescribed in a written

directive will be considered for reporting as an AO.

Date and Place--December 11, 1996; Tuomey Regional Medical Center;

Sumter, South Carolina.

Nature and Probable Consequences--A patient was prescribed a dosage

of 74 megabecquerel (MBq) (2.0 millicurie [mCi]) of iodine-131 (I-131)

for a treatment of Graves disease. However, the patient was

administered a 388.5 MBq (10.5 mCi) dosage of I-131. As a result, the

patient's thyroid received a dose of 40,400 centigray (cGy) (40,400

rad) instead of the prescribed dose of 7700 cGy (7700 rad).

The licensee stated that the administered dose of I-131 to the

patient's thyroid is not expected to have major health effects.

Cause or Causes--The wrong dosage was administered to the patient

because the written order for the I-131 procedure was misread by the

administering technologist.

Actions Taken To Prevent Recurrence

Licensee--The licensee will have the written order on hand before

ordering radiopharmaceuticals from the pharmacy and will have a second

person verify the dosage before administration to the patient.

State Agency--The State Agency accepted the licensee's report and

corrective action as appropriate. No further action was requested.

This event is closed for the purpose of this report.

* * * * *

Dated at Rockville, Maryland this 5th day of May, 1998.

For the Nuclear Regulatory Commission.

John C. Hoyle,

Secretary of the Commission.

[FR Doc. 98-12390 Filed 5-8-98; 8:45 am]

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