Information Notice 1997-36, Unplanned Intakes by Worker of Transuranic Airborne Radioactive Materials and External Exposure Due to Inadequate Control of Work: Difference between revisions

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{{#Wiki_filter:K>UNITED STATES NUCLEAR REGULATORY
{{#Wiki_filter:K>
                                          UNITED STATES


COMMISSION
NUCLEAR REGULATORY COMMISSION


===OFFICE OF NUCLEAR REACTOR REGULATION===
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555-0001 June 20, 1997 NRC INFORMATION


NOTICE 97-36: UNPLANNED
WASHINGTON, D.C. 20555-0001 June 20, 1997 NRC INFORMATION NOTICE 97-36:             UNPLANNED INTAKES BY WORKER OF


INTAKES BY WORKER OF TRANSURANIC
TRANSURANIC AIRBORNE RADIOACTIVE


===AIRBORNE RADIOACTIVE===
MATERIALS AND EXTERNAL EXPOSURE DUE TO
MATERIALS


AND EXTERNAL EXPOSURE DUE TO INADEQUATE
INADEQUATE CONTROL OF WORK
 
CONTROL OF WORK


==Addressees==
==Addressees==
All holders of operating
All holders of operating licenses and construction permits. All licensees of nuclear power


licenses and construction
reactors in the decommissioning stage and fuel cycle licensees.
 
permits. All licensees
 
of nuclear power reactors in the decommissioning
 
stage and fuel cycle licensees.


==Purpose==
==Purpose==
The U.S. Nuclear Regulatory
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice to alert


Commission (NRC) is issuing this information
licensees to inadequate radiological work controls in highly contaminated areas. These


notice to alert licensees
inadequate controls created a substantial potential for personnel radiation exposures in


to inadequate
excess of NRC limits and resulted in unplanned intakes by workers of airborne radioactive


radiological
materials, including transuranics (alpha emitters). It is expected that recipients will review the


work controls in highly contaminated
information in this notice for applicability to their facilities and consider actions, as


areas. These inadequate
appropriate, to avoid similar problems. However, suggestions contained in this information


controls created a substantial
notice are not NRC requirements; therefore, no specific action or written response is


potential
required.


for personnel
==Description of Circumstances==
On November 2, 1996, the Haddam Neck plant was in a refueling and maintenance outage.


radiation
Before flooding the reactor cavity, the fuel transfer canal (FTC), the fuel transfer cart and


exposures
tracks, and the upender needed to be inspected and debris removed to ensure cleanliness.


in excess of NRC limits and resulted in unplanned
In preparation for the inspection and entry to the FTC, two workers (a maintenance


intakes by workers of airborne radioactive
supervisor and a reactor vendor representative) met with health physics (HP) supervisors and


materials, including
HP technicians (HPTs) to discuss the entry. As this work was not on the master outage


transuranics (alpha emitters).
schedule, this was the first notice to HPTs of the work. The governing work procedure


It is expected that recipients
provided no work scope detail. The meeting was not effective; there was no common


will review the information
understanding between the workers and the HPTs as to what work was to be done and the


in this notice for applicability
radiological conditions in the work area. The HPTs mistakenly believed that the workers


to their facilities
would principally walk along the FTC tracks but could periodically leave the tracks to pick up


and consider actions, as appropriate, to avoid similar problems.
debris (e.g., tie wraps) that had fallen down from the charging floor. The HPTs did not know


However, suggestions
that the workers would collect, by hand, paint chips, metal rust, and dried, dirtlike materials


contained
from the floors and walls.


in this information
%          40~)TU2      qq-o-36 417 oao


notice are not NRC requirements;  
tE 1 Cobalqw3;9                                    4;        --
therefore, no specific action or written response is required.Description
                                                                                    -j 3~        1 I


of Circumstances
34)- 1


On November 2, 1996, the Haddam Neck plant was in a refueling
IN 97-36 June 20, 1997 Just before the entry, the HPTs briefed the workers on the radiological conditions. Since the


and maintenance
FTC was decontaminated in August 1996, the workers were led to believe that the canal was


outage.Before flooding the reactor cavity, the fuel transfer canal (FTC), the fuel transfer cart and tracks, and the upender needed to be inspected
generally "clean." The licensee had not performed any prework contamination or radiation


and debris removed to ensure cleanliness.
surveys to support the job. Surveys later found that the FTC contained removable


In preparation
contamination of up to 800 microgrey/h [80 milliradlhr] (beta/gamma) and 500 Bq [30,000
disintegrations per minute) per 100 square centimeters (dpml100 cm2) alpha contamination.


for the inspection
In addition, a local hot spot on the canal floor, readily accessible to the workers, exhibited


and entry to the FTC, two workers (a maintenance
external radiation levels of 250 mSv/h [about 25 R/h] on contact and 80 mSvlh [about 8 R/h]
at waist level. The prework briefing of the workers was inadequate, and the workers were


supervisor
not informed of the actual radiological conditions. Additionally, the work was allowed to


and a reactor vendor representative)
commence under an invalid (because it did not allow FTC entry) radiation work permit
met with health physics (HP) supervisors


and HP technicians (HPTs) to discuss the entry. As this work was not on the master outage schedule, this was the first notice to HPTs of the work. The governing
(RWP), rather than a specific RWP for the FTC. As a result, no comprehensive, prework


work procedure provided no work scope detail. The meeting was not effective;
radiation or contamination surveys were performed. The decision not to issue respiratory
there was no common understanding


between the workers and the HPTs as to what work was to be done and the radiological
protection was based on previous air sample results (after the August 1996 reactor cavity


conditions
decontamination to support worker tours of the area). However, this dated sampling was not


in the work area. The HPTs mistakenly
representative of the extensive debris cleanup activity on November 2, 1996.


believed that the workers would principally
While in the FTC, the workers scraped up debris from the FTC and placed it in a plastic bag.


walk along the FTC tracks but could periodically
Unknown to the workers, this activity generated significant airborne radioactive materials and


leave the tracks to pick up debris (e.g., tie wraps) that had fallen down from the charging floor. The HPTs did not know that the workers would collect, by hand, paint chips, metal rust, and dried, dirtlike materials from the floors and walls.% 40~)TU2 qq-o-36 41 7 oao tE 1 Cobalqw3;9
created a high-intensity external radiation source.
4; --I-j 3~11 IN 97-36 June 20, 1997 Just before the entry, the HPTs briefed the workers on the radiological


conditions.
After completion of the work, one workers dosimeter alarmed upon exiting the reactor cavity.


Since the FTC was decontaminated
The plastic bag of debris was surveyed for the first time and read 200 mSv/h [about 20 R/h]
on contact (it was placed in shielded storage). A later survey of the bag indicated 600 mSv/h


in August 1996, the workers were led to believe that the canal was generally "clean." The licensee had not performed
[about 60 R/h] on contact and about 40 mSv/h [about 4 R/h] about 30 centimeters away. The


any prework contamination
workers wore no additional dosimetry other than their electronic alarming and standard chest


or radiation surveys to support the job. Surveys later found that the FTC contained
thermoluminescence dosimeters (TLDs). The workers found significant contamination, while


removable contamination
whole-body frisking. Nasal smears of the workers indicated 3333 Bq 1200,000 dpmJ


of up to 800 microgrey/h
(beta/gamma) shortly after exiting the cavity. Subsequent to the event, the licensee


[80 milliradlhr] (beta/gamma)  
determined (by analysis and reconstruction) the workers' deep-dose equivalent (DDE), the
and 500 Bq [30,000 disintegrations


per minute) per 100 square centimeters (dpml100 cm 2) alpha contamination.
shallow-dose equivalent (SDE, whole body), the maximum doses to the extremities, and the


In addition, a local hot spot on the canal floor, readily accessible
lens dose equivalent (LDE) from the collection and handling of the debris. None of the


to the workers, exhibited external radiation
worker's external doses were in excess of the limits, with the maximum assigned doses


levels of 250 mSv/h [about 25 R/h] on contact and 80 mSvlh [about 8 R/h]at waist level. The prework briefing of the workers was inadequate, and the workers were not informed of the actual radiological
(mSv) of 4.73 [473 mrem], DDE; 4.73 [473 millirem], SDE; 11.6 [1164 mreml, extremity; and


conditions.
3.97 [397 mrem], LDE.


Additionally, the work was allowed to commence under an invalid (because it did not allow FTC entry) radiation
With the workers out of the cavity, an HPT checked the FTC air sample using a hand-held


work permit (RWP), rather than a specific RWP for the FTC. As a result, no comprehensive, prework radiation
frisker and found that the sample exhibited an elevated count rate, indicating the presence of


or contamination
potential airborne radioactive material. This air sample later indicated about 0.8 derived air


surveys were performed.
concentration (DAC) beta and 24 DAC alpha. The general area air sample was not


===The decision not to issue respiratory===
representative (not in the breathing zone of the workers) of the concentrations encountered
protection


was based on previous air sample results (after the August 1996 reactor cavity decontamination
by the workers during the debris cleanup.


to support worker tours of the area). However, this dated sampling was not representative
A backup air sample of the reactor cavity was started, well away (non-representative) from


of the extensive
the FTC. The sample was also checked in the field with a different (but defective) hand-held


debris cleanup activity on November 2, 1996.While in the FTC, the workers scraped up debris from the FTC and placed it in a plastic bag.Unknown to the workers, this activity generated
IN 97-36 June 20, 1997 frisker, which erroneously indicated no airborne radioactive materials were present. Other


significant
HPTs in the area were then notified (misinformed) that the air within the reactor cavity was


airborne radioactive
clean. The inspector later found that the licensee had failed to establish and implement an


materials
effective program to adequately check for proper operability of the frisker in containment.


and created a high-intensity
On the basis of the erroneous negative air sample result, HPTs authorized two other workers


external radiation
to enter the reactor cavity and clean the reactor vessel stud holes. These workers


source.After completion
unknowingly spent about 15 minutes in an area with elevated airborne radioactive material


of the work, one workers dosimeter
levels and subsequently exited the reactor cavity. Their subsequent whole-body counts


alarmed upon exiting the reactor cavity.The plastic bag of debris was surveyed for the first time and read 200 mSv/h [about 20 R/h]on contact (it was placed in shielded storage).
showed no significant intakes.


A later survey of the bag indicated
The licensee's subsequent counting of the backup air sample prompted identification of the


600 mSv/h[about 60 R/h] on contact and about 40 mSv/h [about 4 R/h] about 30 centimeters
inoperable frisker and subsequent evacuation of the reactor cavity and initiation of an


away. The workers wore no additional
investigation. The backup air sample was found to indicate airborne radioactivity


dosimetry
concentrations of 3.5 DAC beta and 108 DAC alpha. The air sample collected near where


other than their electronic
the two workers were working on the reactor vessel studs was later found to indicate


alarming and standard chest thermoluminescence
1.5 DAC beta and 53 DAC alpha. In spite of these air sample results (high alpha DACs),
their non-representative nature (not near the FTC), and the stay-times of the workers and


dosimeters (TLDs). The workers found significant
their work practices in the FTC (handling contaminated debris), the licensee did not recognize


contamination, while whole-body
the potential for excessive personnel exposure until about a week after the event.


frisking.
Discussion


Nasal smears of the workers indicated
In the Haddam Neck event, inadequate radiological evaluations and controls led to unplanned


3333 Bq 1200,000 dpmJ (beta/gamma)
internal exposures with a substantial potential for worker overexposures. Of more concern
shortly after exiting the cavity. Subsequent


to the event, the licensee determined (by analysis and reconstruction)
was that until identified by an NRC inspector five days after the event, the licensee failed to
the workers' deep-dose


equivalent (DDE), the shallow-dose
recognize the potential for significant internal doses from transuranic radionuclides known to


equivalent (SDE, whole body), the maximum doses to the extremities, and the lens dose equivalent (LDE) from the collection
be present in the FTC. The presence of these alpha-emitting nuclides was evident from


and handling of the debris. None of the worker's external doses were in excess of the limits, with the maximum assigned doses (mSv) of 4.73 [473 mrem], DDE; 4.73 [473 millirem], SDE; 11.6 [1164 mreml, extremity;
loose surface contamination sampling (smears) and air samples. This failure led to untimely
and 3.97 [397 mrem], LDE.With the workers out of the cavity, an HPT checked the FTC air sample using a hand-held frisker and found that the sample exhibited


an elevated count rate, indicating
initiation of in-vitro bioassays (fecal sampling) for the transuranic material intake to assess


the presence of potential
personnel exposures. While the whole-body counting (WBC) indicated a relatively low


airborne radioactive
intake/dose from cobalt-60, the licensee failed to use the high alpha-to-beta gamma ratios


material.
(from the air and smear samples) to identify the potential for significant internal doses to


This air sample later indicated
workers from the transuranic component. When the NRC inspector noted the WBC result for


about 0.8 derived air concentration (DAC) beta and 24 DAC alpha. The general area air sample was not representative (not in the breathing
the gamma emitters (power plant WBC's do not detect alpha radiation) and took into account


zone of the workers) of the concentrations
the relative workplace abundance and typical DAC alpha-to-beta gamma nuclide ratios, he


encountered
informed the licensee of the transuranic concern.


by the workers during the debris cleanup.A backup air sample of the reactor cavity was started, well away (non-representative)
The licensee then initiated fecal sampling to account for doses from all nuclides (including
from the FTC. The sample was also checked in the field with a different (but defective)
hand-held


IN 97-36 June 20, 1997 frisker, which erroneously
alpha emitters). The licensee contracted outside consultants to perform a detailed analysis of


indicated
the event and calculate the workers' internal dose. On the basis of this effort, the licensee


no airborne radioactive
reported a maximum 9.13 mSv [913 mrem] committed effective dose equivalent (CEDE) and


materials
58.7 mSv 15873 mrem] total organ dose equivalent (TODE) to the bone surface. None of the


were present. Other HPTs in the area were then notified (misinformed)
reported doses are In excess of regulatory limits. However, the NRC staff is still reviewing
that the air within the reactor cavity was clean. The inspector


later found that the licensee had failed to establish
the licensee's methods, assumptions and models for the internal dose assessment.


and implement
IN 97-36 June 20, 1997 For reactor facilities that have experienced fuel defects, experience has shown that long after


an effective
the defective fuel has been removed, significant alpha contamination may remain in generally


program to adequately
inaccessible locations, such as the FTC equipment drains and sumps, and other refueling


check for proper operability
areas. Even minor disturbance of the contaminated surfaces can result in the release of


of the frisker in containment.
alpha-emitting radionuclides, whose DACs are orders of magnitude more restrictive and


On the basis of the erroneous
limiting (at much lower concentrations) compared with the normal beta-emitting and gamma- emitting isotopes usually encountered in reactor plant environments (fission, corrosion, and


negative air sample result, HPTs authorized
wear products). Additionally, alpha contamination may be incorporated into a


two other workers to enter the reactor cavity and clean the reactor vessel stud holes. These workers unknowingly
contamination/corrosion layer on the interior surfaces of system components that carry


spent about 15 minutes in an area with elevated airborne radioactive
primary fluids or steam. Surveys for loose surface contamination may not identify the fixed


material levels and subsequently
alpha contamination, but abrasive work (e.g., grinding or welding) may result in alpha- emitting airborne radioactive materials. This latter characteristic may be particularly important


exited the reactor cavity. Their subsequent
at reactor facilities undergoing decommissioning.


whole-body
As a result of this event, the licensee performed root cause analyses. On the basis of these


counts showed no significant
analyses and the findings of an independent review team, the licensee has initiated certain


intakes.The licensee's
corrective actions, which include the following:
1.     All work presenting a significant radiological challenge (within designated high-risk


subsequent
areas) was suspended until a work approval program was instituted. This program


counting of the backup air sample prompted identification
now requires review of all RWPs by the plant Radiation Protection Manager (RPM)
        and the Work Services Director, and RWP approval by the RPM or the Radiological


of the inoperable
Protection Supervisor.


frisker and subsequent
2.      The work control program now includes an RWP procedure requiring clear


evacuation
descriptions of authorized work and controls, improved procedures for high-risk


of the reactor cavity and initiation
evolutions, and representative prework surveys.


of an investigation.
3.      The license stopped the use of in-field counting and checks for air samples as a basis


The backup air sample was found to indicate airborne radioactivity
for reducing or relaxing radiological work controls.


concentrations
4.      All work in high alpha-intake risk areas requires the use of respirators until


of 3.5 DAC beta and 108 DAC alpha. The air sample collected
representative air sampling justifies work without respiratory protection.


near where the two workers were working on the reactor vessel studs was later found to indicate 1.5 DAC beta and 53 DAC alpha. In spite of these air sample results (high alpha DACs), their non-representative
Events involving unplanned intakes of airborne radioactivity at nuclear power plants occur


nature (not near the FTC), and the stay-times
generally during maintenance and refueling outages, are infrequent, and typically result in


of the workers and their work practices
intakes by workers of radioactive material that are well within the limits of 10 CFR Part 20.


in the FTC (handling
However, as indicated in the event describe in this notice, the potential for significant


contaminated
unplanned personnel exposures does exist at nuclear power plants (see related


debris), the licensee did not recognize the potential
correspondence).


for excessive
===Related Communications and Correspondence===
The following related communications and correspondence are noted:
        NRC Inspection Report No. 50-219/96-12, dated December 19, 1996.


personnel
K>~
                                                                          IN 97-36 June 20, 1997 *      NRC Information Notice 90-47, "Unplanned Radiation Exposures to Personnel


exposure until about a week after the event.Discussion
Extremities Due to Improper Handling of Potential Highly Radioactive Sources," dated


In the Haddam Neck event, inadequate
July 27, 1990.


radiological
*      NRC Information Notice 92-75, "Unplanned Intakes of Airborne Radioactive Material


evaluations
by Individuals at Nuclear Power Plants," dated November 12, 1992.


and controls led to unplanned internal exposures
This information notice does not require any specific action or written response. If you have


with a substantial
any questions about the information in this notice, please contact one of the technical


potential
contacts listed below.


for worker overexposures.
Marylee M. Slosson, Acting Direct r


Of more concern was that until identified
Division of Reactor Program Management


by an NRC inspector
Office of Nuclear Reactor Regulation


five days after the event, the licensee failed to recognize
Technical contacts:    Ronald L. Nimitz, RI


the potential
(610) 337-5267 E-mail: rln@nrc.gov


for significant
William J. Raymond, RI


internal doses from transuranic
(860) 267-2571 E-mail: wjr@nrc.gov


radionuclides
James E. Wigginton, NRR


known to be present in the FTC. The presence of these alpha-emitting
301-415-1059 E-mail: jew2@nrc.gov


nuclides was evident from loose surface contamination
Attachment: List of Recently Issued NRC Information Notices


sampling (smears) and air samples. This failure led to untimely initiation
I/d P'      r-          t


of in-vitro bioassays (fecal sampling)
Attachment
for the transuranic


material intake to assess personnel
IN 97-36 June 20, 1997 LIST OF RECENTLY ISSUED


exposures.
NRC INFORMATION NOTICES


While the whole-body
Information                                        Date of


counting (WBC) indicated
Notice No.            Subject                      Issuance  Issued to


a relatively
97-35          Retrofit to Industrial              06/18/97  All industrial radiography


low intake/dose
Nuclear Company (INC)                          licensees


from cobalt-60, the licensee failed to use the high alpha-to-beta
IR100 Radiography Camera


gamma ratios (from the air and smear samples) to identify the potential
to Correct Inconsistency


for significant
in 10 CFR Part 34 Compatibility


internal doses to workers from the transuranic
97-34          Deficiencies in Licensee            06/12/97  All holders of OLs or CPs


component.
Submittals Regarding                          for test and research


When the NRC inspector
Terminology for Radio-                        reactors


noted the WBC result for the gamma emitters (power plant WBC's do not detect alpha radiation)
logical Emergency Action
and took into account the relative workplace


abundance
Levels in Accordance


and typical DAC alpha-to-beta
With the New Part 20
97-33          Unanticipated Effect                06/11/97  All holders of OLs or CPs


gamma nuclide ratios, he informed the licensee of the transuranic
of Ventilation System                          for nuclear power reactors


concern.The licensee then initiated
on Tank Level Indica- tions and Engineering


fecal sampling to account for doses from all nuclides (including
Safety Features Actua- tion System Setpoint


alpha emitters).
95-36,          Potential Problems                  06/10/97  All holders of OLs or CPs


The licensee contracted
Supp. 1        with Post-Fire Emer-                          for nuclear power reactors


outside consultants
gency Lighting


to perform a detailed analysis of the event and calculate
97-32          Defective Worm Shaft                06/10/97  All holders of OLs or CPs


the workers' internal dose. On the basis of this effort, the licensee reported a maximum 9.13 mSv [913 mrem] committed
Clutch Gears in                                for nuclear power reactors


effective
Limitorque Motor- Operated Valve


dose equivalent (CEDE) and 58.7 mSv 15873 mrem] total organ dose equivalent (TODE) to the bone surface. None of the reported doses are In excess of regulatory
Actuators


limits. However, the NRC staff is still reviewing the licensee's
97-31          Failures of Reactor                06/03/97  All holders of OLs or CPs


methods, assumptions
Coolant Pump Thermal                          for pressurized-water


and models for the internal dose assessment.
Barriers and Check                            reactor plants


IN 97-36 June 20, 1997 For reactor facilities
Valves in Foreign


that have experienced
Plants


fuel defects, experience
OL = Operating License


has shown that long after the defective
CP = Construction Permit


fuel has been removed, significant
IN 97-37 June 20, 1997 the fire to spread to that room and could have resulted in the loss of the A switchgear as


alpha contamination
well.


may remain in generally inaccessible
The Pilgrim licensee enhanced the fire protection design in the turbine building by installing


locations, such as the FTC equipment
containment curbs at the fire doors leading to the A essential switchgear room and the


drains and sumps, and other refueling areas. Even minor disturbance
stairway leading to the radwaste holding tanks, and modified the iso-phase bus duct by


of the contaminated
installing an 8-inch diameter downcomer drain line on each of the three phases. Each drain


surfaces can result in the release of alpha-emitting
line is routed to drain into the oil leak retention pit, and will be equipped with a rupture disc


radionuclides, whose DACs are orders of magnitude
designed to open under 2 psig of static oil pressure in the drain line down-comer.


more restrictive
This information notice requires no specific action or written response. If you have any


and limiting (at much lower concentrations)
questions about the Information in this notice, please contact one of the technical contacts
compared with the normal beta-emitting


and gamma-emitting isotopes usually encountered
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.


in reactor plant environments (fission, corrosion, and wear products).
original signed by S.H. Weiss for


Additionally, alpha contamination
Marylee M. Slosson, Acting Director


may be incorporated
Division of Reactor Program Management


into a contamination/corrosion
Office of Nuclear Reactor Regulation


layer on the interior surfaces of system components
Technical contacts:      Patrick Madden, NRR


that carry primary fluids or steam. Surveys for loose surface contamination
301-415-2854 E-mail: pmm@nrc.gov


may not identify the fixed alpha contamination, but abrasive work (e.g., grinding or welding) may result in alpha-emitting airborne radioactive
David Skeen, NRR


materials.
301-415-1174 E-mail: dls2nrc.gov


This latter characteristic
Attachment: List of Recently Issued NRC Information Notices


may be particularly
Tech Editor has reviewed and concurred on 5/19197 DOCUMENT


important at reactor facilities
NAME: G:XDLSUN97-XX.PLG              *SEE PREVIOUS CONCURRENCES


undergoing
OFC      TECH                  C:SPLB              C:PECB                D:(A)DRPM


decommissioning.
==CONTACT==
S


As a result of this event, the licensee performed
NAME      DSkeen*              LMarsh*            AChaffee*            MSloss


root cause analyses.
PMadden*__                  _      _
  DATE      06/02/97            05/27/97            06/13/97              //797      /
            05/27/97


On the basis of these analyses and the findings of an independent
IN 97-XX


review team, the licensee has initiated
June XX, 1997 the fire to spread to that room and could have resulted In the loss of the A switchgear as


certain corrective
well.


actions, which include the following:
The Pilgrim licensee enhanced the fire protection design In the turbine building by installing
1. All work presenting


a significant
containment curbs at the fire doors leading to the A essential switchgear room and the


radiological
stairway leading to the radwaste holding tanks, and modified the Iso-phase bus duct by


challenge (within designated
installing an 8-inch diameter downcomer drain line on each of the three phases. .Each drain


high-risk areas) was suspended
line is routed to drain into the oil leak retention pit, and will be equipped with a rupture disc


until a work approval program was instituted.
designed to open under 2 psig of static oil pressure in the drain line down-comer.


This program now requires review of all RWPs by the plant Radiation
This information notice requires no specific action or written response. If you have any


Protection
questions about the information in this notice, please contact one of the technical contacts


Manager (RPM)and the Work Services Director, and RWP approval by the RPM or the Radiological
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.


Protection
Marylee M. Slosson, Acting Director


Supervisor.
Division of Reactor Program Management


2. The work control program now includes an RWP procedure
Office of Nuclear Reactor Regulation


requiring
Technical contacts:      Patrick Madden, NRR


clear descriptions
301-415-2854 E-mail: pmm@nrc.gov


of authorized
David Skeen, NRR


work and controls, improved procedures
301-415-1174 E-mail: dls@nrc.gov


for high-risk evolutions, and representative
Attachment: List of Recently Issued NRC Information Notices


prework surveys.3. The license stopped the use of in-field counting and checks for air samples as a basis for reducing or relaxing radiological
DOCUMENT NAME: G:XDLSklN97-XX.PLG                      *SEE PREVIOUS CONCURRENCES


work controls.4. All work in high alpha-intake
OFC        TECH                C:SPLB              C:P,                  D:(A)DRPM


risk areas requires the use of respirators
==CONTACT==
 
S_
until representative
  NAME      DSkeen*              LMarsh*A                  ffe.             MSlosson
 
air sampling justifies
 
work without respiratory
 
protection.
 
Events involving
 
unplanned
 
intakes of airborne radioactivity
 
at nuclear power plants occur generally
 
during maintenance
 
and refueling
 
outages, are infrequent, and typically
 
result in intakes by workers of radioactive
 
material that are well within the limits of 10 CFR Part 20.However, as indicated
 
in the event describe in this notice, the potential
 
for significant
 
unplanned
 
personnel
 
exposures
 
does exist at nuclear power plants (see related correspondence).
 
Related Communications
 
and Correspondence
 
The following
 
related communications
 
and correspondence
 
are noted: NRC Inspection
 
Report No. 50-219/96-12, dated December 19, 1996.


K>~IN 97-36 June 20, 1997
PMadden*
* NRC Information
  DATE      06102197            05/27/97              A97                    1/97
            05127197 OAFFICIAL KRECOKR W        TYj


Notice 90-47, "Unplanned
0&          bll-P-8


Radiation
IN 97-XX


Exposures
June XX, 1997 the fire to spread to that room and could have resulted in the loss of the A switchgear as


to Personnel Extremities
well.


Due to Improper Handling of Potential
The Pilgrim licensee enhanced the fire protection design in the turbine building by installing


Highly Radioactive
containment curbs at the fire doors leading to the A essential switchgear room and the


Sources," dated July 27, 1990.* NRC Information
stairway leading to the radwaste holding tanks, and modified the iso-phase bus duct by


Notice 92-75, "Unplanned
installing an 8-inch diameter downcomer drain line on each of the three phases. Each drain


Intakes of Airborne Radioactive
line is routed to drain into the oil leak retention pit, and will be equipped with a rupture disc


Material by Individuals
designed to open under 2 psig of static oil pressure in the drain line down-comer.


at Nuclear Power Plants," dated November 12, 1992.This information
This information notice requires no specific action or written response. If you have any


notice does not require any specific action or written response.
questions about the information in this notice, please contact one of the technical contacts


If you have any questions
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.


about the information
Marylee M. Slosson, Acting Director


in this notice, please contact one of the technical contacts listed below.Marylee M. Slosson, Acting Direct r Division of Reactor Program Management
Division of Reactor Program Management


===Office of Nuclear Reactor Regulation===
Office of Nuclear Reactor Regulation
Technical


contacts:  
Technical contacts:     Patrick Madden, NRR
Ronald L. Nimitz, RI (610) 337-5267 E-mail: rln@nrc.gov


William J. Raymond, RI (860) 267-2571 E-mail: wjr@nrc.gov
(301) 415-2854 E-mail: pmmenrc.gov


James E. Wigginton, NRR 301-415-1059 E-mail: jew2@nrc.gov
David Skeen, NRR


Attachment:  
(301) 415-1174 E-mail: dlsenrc.gov
List of Recently Issued NRC Information


Notices I/d P' r -t
Attachment: List of Recently Issued NRC Information Notices


Attachment
DOCUMENT NAME: G:\DLS\lN97-XX.PLG


IN 97-36 June 20, 1997 LIST OF RECENTLY ISSUED NRC INFORMATION
OFC        TECH                C:SPLB              C:PECB                D:(A)DRPM


NOTICES Information
___ __   
 
Date of Notice No. Subject Issuance Issued to 97-35 97-34 97-33 Retrofit to Industrial
 
Nuclear Company (INC)IR100 Radiography
 
===Camera to Correct Inconsistency===
in 10 CFR Part 34 Compatibility
 
Deficiencies
 
in Licensee Submittals
 
Regarding Terminology
 
for Radio-logical Emergency
 
===Action Levels in Accordance===
With the New Part 20 Unanticipated
 
Effect of Ventilation
 
System on Tank Level Indica-tions and Engineering
 
Safety Features Actua-tion System Setpoint Potential
 
Problems with Post-Fire
 
Emer-gency Lighting Defective
 
Worm Shaft Clutch Gears in Limitorque
 
Motor-Operated Valve Actuators Failures of Reactor Coolant Pump Thermal Barriers and Check Valves in Foreign Plants 06/18/97 06/12/97 06/11/97 06/10/97 06/10/97 06/03/97 All industrial
 
radiography
 
licensees All holders of OLs or CPs for test and research reactors All holders of OLs or CPs for nuclear power reactors All holders of OLs or CPs for nuclear power reactors All holders of OLs or CPs for nuclear power reactors All holders of OLs or CPs for pressurized-water
 
reactor plants 95-36, Supp. 1 97-32 97-31 OL = Operating
 
License CP = Construction
 
Permit
 
IN 97-37 June 20, 1997 the fire to spread to that room and could have resulted in the loss of the A switchgear
 
as well.The Pilgrim licensee enhanced the fire protection
 
design in the turbine building by installing
 
containment
 
curbs at the fire doors leading to the A essential
 
switchgear
 
room and the stairway leading to the radwaste holding tanks, and modified the iso-phase
 
bus duct by installing
 
an 8-inch diameter downcomer
 
drain line on each of the three phases. Each drain line is routed to drain into the oil leak retention
 
pit, and will be equipped with a rupture disc designed to open under 2 psig of static oil pressure in the drain line down-comer.
 
This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about the Information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
Office of Nuclear Reactor Regulation (NRR) project manager.original signed by S.H. Weiss for Marylee M. Slosson, Acting Director Division of Reactor Program Management
 
===Office of Nuclear Reactor Regulation===
Technical
 
contacts: Patrick Madden, NRR 301-415-2854 E-mail: pmm@nrc.gov
 
David Skeen, NRR 301-415-1174 E-mail: dls2nrc.gov
 
Attachment:
List of Recently Issued NRC Information
 
Notices Tech Editor has reviewed and concurred
 
on 5/19197 DOCUMENT NAME: G:XDLSUN97-XX.PLG
 
*SEE PREVIOUS CONCURRENCES
 
OFC TECH C:SPLB C:PECB D:(A)DRPM


==CONTACT==
==CONTACT==
S NAME DSkeen* LMarsh* AChaffee*
S__                _  _  _  _  __                          _  _  _  _  _
MSloss PMadden*__
  NAME       DS                    LMarsh go-,         AChaffee              MSlosson
_ _DATE 06/02/97 05/27/97 06/13/97 //797 /05/27/97 IN 97-XX June XX, 1997 the fire to spread to that room and could have resulted In the loss of the A switchgear


as well.The Pilgrim licensee enhanced the fire protection
DATE                  5797      ,97                    /97                  /97 OFFICIAL RECORD COPY]


design In the turbine building by installing
'
                                                                                      IN 97-XX


containment
Month XX, 1997 The Pilgrim licensee enhanced the fire protection design in the turbine building by installing
 
curbs at the fire doors leading to the A essential
 
switchgear
 
room and the stairway leading to the radwaste holding tanks, and modified the Iso-phase
 
bus duct by installing
 
an 8-inch diameter downcomer
 
drain line on each of the three phases. .Each drain line is routed to drain into the oil leak retention
 
pit, and will be equipped with a rupture disc designed to open under 2 psig of static oil pressure in the drain line down-comer.
 
This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about the information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
Office of Nuclear Reactor Regulation (NRR) project manager.Marylee M. Slosson, Acting Director Division of Reactor Program Management
 
===Office of Nuclear Reactor Regulation===
Technical
 
contacts: Patrick Madden, NRR 301-415-2854 E-mail: pmm@nrc.gov
 
David Skeen, NRR 301-415-1174 E-mail: dls@nrc.gov
 
Attachment:
List of Recently Issued NRC Information
 
Notices DOCUMENT NAME: G:XDLSklN97-XX.PLG
 
*SEE PREVIOUS CONCURRENCES
 
OFC TECH C:SPLB C:P, D:(A)DRPM
 
==CONTACT==
S_NAME DSkeen* LMarsh*A ffe. MSlosson PMadden*DATE 06102197 05/27/97 A 97 1 /97 05127197 OAFFICIAL
 
KRECOKR W TYj 0& bll-P-8 IN 97-XX June XX, 1997 the fire to spread to that room and could have resulted in the loss of the A switchgear
 
as well.The Pilgrim licensee enhanced the fire protection
 
design in the turbine building by installing
 
containment
 
curbs at the fire doors leading to the A essential
 
switchgear
 
room and the stairway leading to the radwaste holding tanks, and modified the iso-phase
 
bus duct by installing
 
an 8-inch diameter downcomer
 
drain line on each of the three phases. Each drain line is routed to drain into the oil leak retention
 
pit, and will be equipped with a rupture disc designed to open under 2 psig of static oil pressure in the drain line down-comer.
 
This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about the information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
Office of Nuclear Reactor Regulation (NRR) project manager.Marylee M. Slosson, Acting Director Division of Reactor Program Management
 
===Office of Nuclear Reactor Regulation===
Technical
 
contacts:
Patrick Madden, NRR (301) 415-2854 E-mail: pmmenrc.gov
 
David Skeen, NRR (301) 415-1174 E-mail: dlsenrc.gov
 
Attachment:
List of Recently Issued NRC Information
 
Notices DOCUMENT NAME: G:\DLS\lN97-XX.PLG
 
OFC TECH C:SPLB C:PECB D:(A)DRPM___ __
 
==CONTACT==
S__
_ _ _ _ __ _ _ _ _ _NAME DS LMarsh go-, AChaffee MSlosson DATE 5797 ,97 /97 /97 OFFICIAL RECORD COPY]
'IN 97-XX Month XX, 1997 The Pilgrim licensee enhanced the fire protection


design in the turbine building by installing
containment curbs at the fire doors leading to the A essential switchgear room and the


containment
stairway leading to the radwaste holding tanks, and modified the iso-phase bus duct by


curbs at the fire doors leading to the A essential
installing an 8-inch diameter downcomer drain line on each of the three phases. Each drain


switchgear
line is routed to drain into the oil leak retention pit, and will be equipped with a rupture disc


room and the stairway leading to the radwaste holding tanks, and modified the iso-phase
designed to open under 2 psig of static oil pressure in the drain line down-comer.


bus duct by installing
This information notice requires no specific action or written response. If you have any


an 8-inch diameter downcomer
questions about the information in this notice, please contact one of the technical contacts


drain line on each of the three phases. Each drain line is routed to drain into the oil leak retention
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.


pit, and will be equipped with a rupture disc designed to open under 2 psig of static oil pressure in the drain line down-comer.
Marylee M. Slosson, Acting Director


This information
Division of Reactor Program Management


notice requires no specific action or written response.
Office of Nuclear Reactor Regulation


If you have any questions
Technical contacts: Patrick Madden, NRR


about the information
(301) 415-2854 E-mail: pmm@nrc.gov


in this notice, please contact one of the technical
David Skeen, NRR


contacts listed below or the appropriate
(301) 415-1174 E-mail: dls@nrc.gov


Office of Nuclear Reactor Regulation (NRR) project manager.Marylee M. Slosson, Acting Director Division of Reactor Program Management
Attachment: List of Recently Issued NRC Information Notices


===Office of Nuclear Reactor Regulation===
DOCUMENT NAME: G:IDLSUIN97-XX.PLG
Technical


contacts:  
OFC      TECH                C:SPLBAA            C:PECB                D:(A)DRPM
Patrick Madden, NRR (301) 415-2854 E-mail: pmm@nrc.gov


David Skeen, NRR (301) 415-1174 E-mail: dls@nrc.gov
CONT,,                      B


Attachment:
NAME      DSkee                LMarsh v            AChaffee              MSlosson
List of Recently Issued NRC Information


Notices DOCUMENT NAME: G:IDLSUIN97-XX.PLG
PMadden    fdL.


OFC TECH C:SPLBAA C:PECB D:(A)DRPM CONT,, B NAME DSkee LMarsh v AChaffee MSlosson PMadden fdL.DATE I?/97 I2197 I //97 / /97 OFFICIAL RECORD COPY]}}
DATE     I?/97               I2197               I //97                 / /97 OFFICIAL RECORD COPY]}}


{{Information notice-Nav}}
{{Information notice-Nav}}

Revision as of 04:39, 24 November 2019

Unplanned Intakes by Worker of Transuranic Airborne Radioactive Materials and External Exposure Due to Inadequate Control of Work
ML031050563
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, 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, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant, Crane  
Issue date: 06/20/1997
From: Slosson M
Office of Nuclear Reactor Regulation
To:
References
IN-97-036, NUDOCS 9706170322
Download: ML031050563 (10)
v • d • e


K>

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555-0001 June 20, 1997 NRC INFORMATION NOTICE 97-36: UNPLANNED INTAKES BY WORKER OF

TRANSURANIC AIRBORNE RADIOACTIVE

MATERIALS AND EXTERNAL EXPOSURE DUE TO

INADEQUATE CONTROL OF WORK

Addressees

All holders of operating licenses and construction permits. All licensees of nuclear power

reactors in the decommissioning stage and fuel cycle licensees.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice to alert

licensees to inadequate radiological work controls in highly contaminated areas. These

inadequate controls created a substantial potential for personnel radiation exposures in

excess of NRC limits and resulted in unplanned intakes by workers of airborne radioactive

materials, including transuranics (alpha emitters). It is expected that recipients will review the

information in this notice 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.

Description of Circumstances

On November 2, 1996, the Haddam Neck plant was in a refueling and maintenance outage.

Before flooding the reactor cavity, the fuel transfer canal (FTC), the fuel transfer cart and

tracks, and the upender needed to be inspected and debris removed to ensure cleanliness.

In preparation for the inspection and entry to the FTC, two workers (a maintenance

supervisor and a reactor vendor representative) met with health physics (HP) supervisors and

HP technicians (HPTs) to discuss the entry. As this work was not on the master outage

schedule, this was the first notice to HPTs of the work. The governing work procedure

provided no work scope detail. The meeting was not effective; there was no common

understanding between the workers and the HPTs as to what work was to be done and the

radiological conditions in the work area. The HPTs mistakenly believed that the workers

would principally walk along the FTC tracks but could periodically leave the tracks to pick up

debris (e.g., tie wraps) that had fallen down from the charging floor. The HPTs did not know

that the workers would collect, by hand, paint chips, metal rust, and dried, dirtlike materials

from the floors and walls.

% 40~)TU2 qq-o-36 417 oao

tE 1 Cobalqw3;9 4; --

-j 3~ 1 I

34)- 1

IN 97-36 June 20, 1997 Just before the entry, the HPTs briefed the workers on the radiological conditions. Since the

FTC was decontaminated in August 1996, the workers were led to believe that the canal was

generally "clean." The licensee had not performed any prework contamination or radiation

surveys to support the job. Surveys later found that the FTC contained removable

contamination of up to 800 microgrey/h [80 milliradlhr] (beta/gamma) and 500 Bq [30,000

disintegrations per minute) per 100 square centimeters (dpml100 cm2) alpha contamination.

In addition, a local hot spot on the canal floor, readily accessible to the workers, exhibited

external radiation levels of 250 mSv/h [about 25 R/h] on contact and 80 mSvlh [about 8 R/h]

at waist level. The prework briefing of the workers was inadequate, and the workers were

not informed of the actual radiological conditions. Additionally, the work was allowed to

commence under an invalid (because it did not allow FTC entry) radiation work permit

(RWP), rather than a specific RWP for the FTC. As a result, no comprehensive, prework

radiation or contamination surveys were performed. The decision not to issue respiratory

protection was based on previous air sample results (after the August 1996 reactor cavity

decontamination to support worker tours of the area). However, this dated sampling was not

representative of the extensive debris cleanup activity on November 2, 1996.

While in the FTC, the workers scraped up debris from the FTC and placed it in a plastic bag.

Unknown to the workers, this activity generated significant airborne radioactive materials and

created a high-intensity external radiation source.

After completion of the work, one workers dosimeter alarmed upon exiting the reactor cavity.

The plastic bag of debris was surveyed for the first time and read 200 mSv/h [about 20 R/h]

on contact (it was placed in shielded storage). A later survey of the bag indicated 600 mSv/h

[about 60 R/h] on contact and about 40 mSv/h [about 4 R/h] about 30 centimeters away. The

workers wore no additional dosimetry other than their electronic alarming and standard chest

thermoluminescence dosimeters (TLDs). The workers found significant contamination, while

whole-body frisking. Nasal smears of the workers indicated 3333 Bq 1200,000 dpmJ

(beta/gamma) shortly after exiting the cavity. Subsequent to the event, the licensee

determined (by analysis and reconstruction) the workers' deep-dose equivalent (DDE), the

shallow-dose equivalent (SDE, whole body), the maximum doses to the extremities, and the

lens dose equivalent (LDE) from the collection and handling of the debris. None of the

worker's external doses were in excess of the limits, with the maximum assigned doses

(mSv) of 4.73 [473 mrem], DDE; 4.73 [473 millirem], SDE; 11.6 [1164 mreml, extremity; and

3.97 [397 mrem], LDE.

With the workers out of the cavity, an HPT checked the FTC air sample using a hand-held

frisker and found that the sample exhibited an elevated count rate, indicating the presence of

potential airborne radioactive material. This air sample later indicated about 0.8 derived air

concentration (DAC) beta and 24 DAC alpha. The general area air sample was not

representative (not in the breathing zone of the workers) of the concentrations encountered

by the workers during the debris cleanup.

A backup air sample of the reactor cavity was started, well away (non-representative) from

the FTC. The sample was also checked in the field with a different (but defective) hand-held

IN 97-36 June 20, 1997 frisker, which erroneously indicated no airborne radioactive materials were present. Other

HPTs in the area were then notified (misinformed) that the air within the reactor cavity was

clean. The inspector later found that the licensee had failed to establish and implement an

effective program to adequately check for proper operability of the frisker in containment.

On the basis of the erroneous negative air sample result, HPTs authorized two other workers

to enter the reactor cavity and clean the reactor vessel stud holes. These workers

unknowingly spent about 15 minutes in an area with elevated airborne radioactive material

levels and subsequently exited the reactor cavity. Their subsequent whole-body counts

showed no significant intakes.

The licensee's subsequent counting of the backup air sample prompted identification of the

inoperable frisker and subsequent evacuation of the reactor cavity and initiation of an

investigation. The backup air sample was found to indicate airborne radioactivity

concentrations of 3.5 DAC beta and 108 DAC alpha. The air sample collected near where

the two workers were working on the reactor vessel studs was later found to indicate

1.5 DAC beta and 53 DAC alpha. In spite of these air sample results (high alpha DACs),

their non-representative nature (not near the FTC), and the stay-times of the workers and

their work practices in the FTC (handling contaminated debris), the licensee did not recognize

the potential for excessive personnel exposure until about a week after the event.

Discussion

In the Haddam Neck event, inadequate radiological evaluations and controls led to unplanned

internal exposures with a substantial potential for worker overexposures. Of more concern

was that until identified by an NRC inspector five days after the event, the licensee failed to

recognize the potential for significant internal doses from transuranic radionuclides known to

be present in the FTC. The presence of these alpha-emitting nuclides was evident from

loose surface contamination sampling (smears) and air samples. This failure led to untimely

initiation of in-vitro bioassays (fecal sampling) for the transuranic material intake to assess

personnel exposures. While the whole-body counting (WBC) indicated a relatively low

intake/dose from cobalt-60, the licensee failed to use the high alpha-to-beta gamma ratios

(from the air and smear samples) to identify the potential for significant internal doses to

workers from the transuranic component. When the NRC inspector noted the WBC result for

the gamma emitters (power plant WBC's do not detect alpha radiation) and took into account

the relative workplace abundance and typical DAC alpha-to-beta gamma nuclide ratios, he

informed the licensee of the transuranic concern.

The licensee then initiated fecal sampling to account for doses from all nuclides (including

alpha emitters). The licensee contracted outside consultants to perform a detailed analysis of

the event and calculate the workers' internal dose. On the basis of this effort, the licensee

reported a maximum 9.13 mSv [913 mrem] committed effective dose equivalent (CEDE) and

58.7 mSv 15873 mrem] total organ dose equivalent (TODE) to the bone surface. None of the

reported doses are In excess of regulatory limits. However, the NRC staff is still reviewing

the licensee's methods, assumptions and models for the internal dose assessment.

IN 97-36 June 20, 1997 For reactor facilities that have experienced fuel defects, experience has shown that long after

the defective fuel has been removed, significant alpha contamination may remain in generally

inaccessible locations, such as the FTC equipment drains and sumps, and other refueling

areas. Even minor disturbance of the contaminated surfaces can result in the release of

alpha-emitting radionuclides, whose DACs are orders of magnitude more restrictive and

limiting (at much lower concentrations) compared with the normal beta-emitting and gamma- emitting isotopes usually encountered in reactor plant environments (fission, corrosion, and

wear products). Additionally, alpha contamination may be incorporated into a

contamination/corrosion layer on the interior surfaces of system components that carry

primary fluids or steam. Surveys for loose surface contamination may not identify the fixed

alpha contamination, but abrasive work (e.g., grinding or welding) may result in alpha- emitting airborne radioactive materials. This latter characteristic may be particularly important

at reactor facilities undergoing decommissioning.

As a result of this event, the licensee performed root cause analyses. On the basis of these

analyses and the findings of an independent review team, the licensee has initiated certain

corrective actions, which include the following:

1. All work presenting a significant radiological challenge (within designated high-risk

areas) was suspended until a work approval program was instituted. This program

now requires review of all RWPs by the plant Radiation Protection Manager (RPM)

and the Work Services Director, and RWP approval by the RPM or the Radiological

Protection Supervisor.

2. The work control program now includes an RWP procedure requiring clear

descriptions of authorized work and controls, improved procedures for high-risk

evolutions, and representative prework surveys.

3. The license stopped the use of in-field counting and checks for air samples as a basis

for reducing or relaxing radiological work controls.

4. All work in high alpha-intake risk areas requires the use of respirators until

representative air sampling justifies work without respiratory protection.

Events involving unplanned intakes of airborne radioactivity at nuclear power plants occur

generally during maintenance and refueling outages, are infrequent, and typically result in

intakes by workers of radioactive material that are well within the limits of 10 CFR Part 20.

However, as indicated in the event describe in this notice, the potential for significant

unplanned personnel exposures does exist at nuclear power plants (see related

correspondence).

Related Communications and Correspondence

The following related communications and correspondence are noted:

NRC Inspection Report No. 50-219/96-12, dated December 19, 1996.

K>~

IN 97-36 June 20, 1997 * NRC Information Notice 90-47, "Unplanned Radiation Exposures to Personnel

Extremities Due to Improper Handling of Potential Highly Radioactive Sources," dated

July 27, 1990.

by Individuals at Nuclear Power Plants," dated November 12, 1992.

This information notice does not require any specific action or written response. If you have

any questions about the information in this notice, please contact one of the technical

contacts listed below.

Marylee M. Slosson, Acting Direct r

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical contacts: Ronald L. Nimitz, RI

(610) 337-5267 E-mail: rln@nrc.gov

William J. Raymond, RI

(860) 267-2571 E-mail: wjr@nrc.gov

James E. Wigginton, NRR

301-415-1059 E-mail: jew2@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

I/d P' r- t

Attachment

IN 97-36 June 20, 1997 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

97-35 Retrofit to Industrial 06/18/97 All industrial radiography

Nuclear Company (INC) licensees

IR100 Radiography Camera

to Correct Inconsistency

in 10 CFR Part 34 Compatibility

97-34 Deficiencies in Licensee 06/12/97 All holders of OLs or CPs

Submittals Regarding for test and research

Terminology for Radio- reactors

logical Emergency Action

Levels in Accordance

With the New Part 20

97-33 Unanticipated Effect 06/11/97 All holders of OLs or CPs

of Ventilation System for nuclear power reactors

on Tank Level Indica- tions and Engineering

Safety Features Actua- tion System Setpoint

95-36, Potential Problems 06/10/97 All holders of OLs or CPs

Supp. 1 with Post-Fire Emer- for nuclear power reactors

gency Lighting

97-32 Defective Worm Shaft 06/10/97 All holders of OLs or CPs

Clutch Gears in for nuclear power reactors

Limitorque Motor- Operated Valve

Actuators

97-31 Failures of Reactor 06/03/97 All holders of OLs or CPs

Coolant Pump Thermal for pressurized-water

Barriers and Check reactor plants

Valves in Foreign

Plants

OL = Operating License

CP = Construction Permit

IN 97-37 June 20, 1997 the fire to spread to that room and could have resulted in the loss of the A switchgear as

well.

The Pilgrim licensee enhanced the fire protection design in the turbine building by installing

containment curbs at the fire doors leading to the A essential switchgear room and the

stairway leading to the radwaste holding tanks, and modified the iso-phase bus duct by

installing an 8-inch diameter downcomer drain line on each of the three phases. Each drain

line is routed to drain into the oil leak retention pit, and will be equipped with a rupture disc

designed to open under 2 psig of static oil pressure in the drain line down-comer.

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

questions about the Information in this notice, please contact one of the technical contacts

listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.

original signed by S.H. Weiss for

Marylee M. Slosson, Acting Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical contacts: Patrick Madden, NRR

301-415-2854 E-mail: pmm@nrc.gov

David Skeen, NRR

301-415-1174 E-mail: dls2nrc.gov

Attachment: List of Recently Issued NRC Information Notices

Tech Editor has reviewed and concurred on 5/19197 DOCUMENT

NAME: G:XDLSUN97-XX.PLG *SEE PREVIOUS CONCURRENCES

OFC TECH C:SPLB C:PECB D:(A)DRPM

CONTACT

S

NAME DSkeen* LMarsh* AChaffee* MSloss

PMadden*__ _ _

DATE 06/02/97 05/27/97 06/13/97 //797 /

05/27/97

IN 97-XX

June XX, 1997 the fire to spread to that room and could have resulted In the loss of the A switchgear as

well.

The Pilgrim licensee enhanced the fire protection design In the turbine building by installing

containment curbs at the fire doors leading to the A essential switchgear room and the

stairway leading to the radwaste holding tanks, and modified the Iso-phase bus duct by

installing an 8-inch diameter downcomer drain line on each of the three phases. .Each drain

line is routed to drain into the oil leak retention pit, and will be equipped with a rupture disc

designed to open under 2 psig of static oil pressure in the drain line down-comer.

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

questions about the information in this notice, please contact one of the technical contacts

listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.

Marylee M. Slosson, Acting Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical contacts: Patrick Madden, NRR

301-415-2854 E-mail: pmm@nrc.gov

David Skeen, NRR

301-415-1174 E-mail: dls@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

DOCUMENT NAME: G:XDLSklN97-XX.PLG *SEE PREVIOUS CONCURRENCES

OFC TECH C:SPLB C:P, D:(A)DRPM

CONTACT

S_

NAME DSkeen* LMarsh*A ffe. MSlosson

PMadden*

DATE 06102197 05/27/97 A97 1/97

05127197 OAFFICIAL KRECOKR W TYj

0& bll-P-8

IN 97-XX

June XX, 1997 the fire to spread to that room and could have resulted in the loss of the A switchgear as

well.

The Pilgrim licensee enhanced the fire protection design in the turbine building by installing

containment curbs at the fire doors leading to the A essential switchgear room and the

stairway leading to the radwaste holding tanks, and modified the iso-phase bus duct by

installing an 8-inch diameter downcomer drain line on each of the three phases. Each drain

line is routed to drain into the oil leak retention pit, and will be equipped with a rupture disc

designed to open under 2 psig of static oil pressure in the drain line down-comer.

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

questions about the information in this notice, please contact one of the technical contacts

listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.

Marylee M. Slosson, Acting Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical contacts: Patrick Madden, NRR

(301) 415-2854 E-mail: pmmenrc.gov

David Skeen, NRR

(301) 415-1174 E-mail: dlsenrc.gov

Attachment: List of Recently Issued NRC Information Notices

DOCUMENT NAME: G:\DLS\lN97-XX.PLG

OFC TECH C:SPLB C:PECB D:(A)DRPM

___ __

CONTACT

S__ _ _ _ _ __ _ _ _ _ _

NAME DS LMarsh go-, AChaffee MSlosson

DATE 5797 ,97 /97 /97 OFFICIAL RECORD COPY]

'

IN 97-XX

Month XX, 1997 The Pilgrim licensee enhanced the fire protection design in the turbine building by installing

containment curbs at the fire doors leading to the A essential switchgear room and the

stairway leading to the radwaste holding tanks, and modified the iso-phase bus duct by

installing an 8-inch diameter downcomer drain line on each of the three phases. Each drain

line is routed to drain into the oil leak retention pit, and will be equipped with a rupture disc

designed to open under 2 psig of static oil pressure in the drain line down-comer.

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

questions about the information in this notice, please contact one of the technical contacts

listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.

Marylee M. Slosson, Acting Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical contacts: Patrick Madden, NRR

(301) 415-2854 E-mail: pmm@nrc.gov

David Skeen, NRR

(301) 415-1174 E-mail: dls@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

DOCUMENT NAME: G:IDLSUIN97-XX.PLG

OFC TECH C:SPLBAA C:PECB D:(A)DRPM

CONT,, B

NAME DSkee LMarsh v AChaffee MSlosson

PMadden fdL.

DATE I?/97 I2197 I //97 / /97 OFFICIAL RECORD COPY]


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