ML17191A599
| ML17191A599 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 04/10/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML17191A597 | List: |
| References | |
| 50-237-98-11, 50-249-98-11, NUDOCS 9804170111 | |
| Download: ML17191A599 (13) | |
See also: IR 05000237/1998011
Text
U.S. NUCLEAR REGULATORY COMMISSION
Docket Nos:
License Nos:
Report Nos:
Ucensee:
Facility:
Location:
Dates:
Inspectors:
Approved by:
9804170111 980410
ADOCK 05000237
G
REGION Ill
50-237; 50-249
50-237/98011 (DRS); 50-249/98011 (DRS)
Commonwealth Edison .
Dresden Nuclear Generating Station, Units 2 and 3
6500 N. Dresden Road
Morris, IL 60540
March 16-20 and 23-24, 1998
W. Slawinski, Senior Radiatfon Specialist
R. Paul, Senior Radiation Specialist
Gary L. Shear, Chief, Plant Support Branch 2
Division or Reactor Safety
EXECUTIVE SUMMARY
Dresden Generating Station, Units 2 and 3
NRC Inspection Reports 50-237/98011; 50-249/98011
This inspection consisted of a review of the radiological planning and work control processes,
the overall radiological performance, and the effectiveness of the as-low-as-is-reasonably-
achievable (ALARA) program and associated dose controls for the ongoing Unit 2 refueling
- outage. In these areas, the following conclusions were formed:
Although there was no significant dose producing emergent work and rework during the
outage, work scope additions after the outage dose goals were established contributed .
to some early accelerated outage work and associated dose. With the exception of
weaknesses associated primarily with the scaffolding construction program, the
planning, scheduling and implementation of the outage work process was sufficient
(Section R1 .1 ).
Radiological control of work activities was good with some exceptions related to
occasional drywell work coordination and oversight problems. ALARA initiatives,
engineering controls and job planning were effectively implemented, and efforts to
control dose, prevent intake of radioactive material and limit personnel contamination
events were successful (Section R1 .2).
Radiation worker (radworker) practices improved as the outage progressed and in
general, were better than previous refueling outages. Initiatives such as the greeter
program, increased emphasis on worker responsibility, first line supervisory oversight
and stronger radiation protection (RP) control point oversight, were instrumental in
reducing poor radworker practices. While the station's aggressive approach in
challenging craft workers about crew size and knowledge of the radiological work
environment had some positive effect on contractor work control and dose, continued
emphasis in this area is warranted (Section R4.1 ).
Radiological housekeeping and control and labeling of radioactive material was good \\n
most areas. However, general housekeeping in certain areas of the drywell was poor,
and a water drip from a known leaky valve in the drywell was apparently not addressed
until the*problem was brought to the licensee's attention by the inspectors. While
radiation area posting discrepancies were noted in the reactor building, areas were
posted and controlled in accordance with NRC requirements (Section R4.2).
The training of prospective contract (RP) staff was completed in accordance with station
procedures, and adequately prepared workers for assigned outage tasks (Section R5).
Administration of the RP program during the first half of the planned 40-day outage was
generally good, and was not adversely affected by the RP organization changes made
just prior to the outage, and the unexpected loss of several contract radiation protection
support staff early in the outage (Section R6).
2
DETAILS
IV. PLANT SUPPORT
R.1
Radiological Protection and Chemistry (RP&C) Controls
R1 .1
Radiological Planning for the Refueling Outage
a.
Inspection Scope (IP 83729)
The inspectors reviewed the overall radiological planning and dose goal development
for the Unit 2 refueling outage (D2R15). The review consisted of discussions with as-
low-as-i~reasonably-achievable (ALARA) and outage planning groups; review of the
planned outage work and work scope growth issues, certain work processes and
relevant procedures; and discussions with workers, work control groups and contract
craft management.
b.
Observations and Findings
The licensee's dose goal for D2R15 was 225 rem, which appeared aggressive given the
scope of the work activities, and the 30 % greater Unit 2 drywell source term relative to
Unit 3. Also, no chemical decontamination of the Unit 2 reactor recirculation suction and
discharge piping was performed because the licensee's dose to cost benefit analysis
concluded it was not justified. The dose goal included estimated contributions from
rework, contingent and projected emergent work, and added scope work. Although the
projected dose included about nine rem for emergent and rework, no significant
emergent or rework took place to date. However, considerable work scope was added
since the projected dose was established in mid-December 1997. Specifically, work
scope estimated at about 15 to 20 rem was added to the D2R 15 dose, and included
drywell ventilation maintenance, drywell recirculation piping weld overlay, and isolation
condenser system and components maintenance. About midway through the outage,
the station was running about 13 rem over its dose goal because of an accelerated work
schedule at the beginning of the outage, and because greater than projected dose was
expended for drywell scaffold construction and insulation work. The accelerated
activities included some of the added scope work. Although this additional dose was not
accounted for in the dose goal projected in December 1997, the dose goals were not
changed due to the nature of the remaining work, and because the ALARA group
estimated that the station c;ould make up the dose difference by continuing to minimize
emergent work and rework. With approximately 80% of the outage work completed, the
station had recouped some of the additional dose expended earlier in the outage, and
was running about 5 rem over its goal at that time.
'
The most radiologically significant outage activities included scaffold construction
(estimated at 24 person-rem); drywell in service inspection activities (estimated at 11
person-rem); drywell control rod drive system pull/put maintenance work (estimated at
18 person-rem); drywell insulation removal, installation and maintenance (estimated at 7
person-rem); control rod drive system maintenance activities (estimated at 6 person-
3
rem); and condensate demineralizer system maintenance activities (estimated at 4
person-rem). As of April 2, 1998, with the outage about 80 % complete, the station had
accrued an annual dose of 224 rem, of which 181 rem was attributed to the outage.
Contingencies were in place for the major dose producing jobs, lessons learned from
previous outages were incorporated into the planning, and the radiation protection (RP)
group was adequately involved in the planning process.
For this outage, the licensee used the "minimal work request" process, which was
intended to allow minor work scope activities to be accomplished without having to
satisfy the more rigorous review and process controls and screening required for a
typical maintenance work request. This was the first time the station used the minimal
work pro"teSs, and it was in part responsible for problems associated with the scaffold
construction process encountered during the early part of D2R 15. The problems
consisted of erecting scaffolds without knowledge of load bearing requirements, and the
installation of scaffolds that were not necessary. It appeared there was no organized
flow path from scaffolding request to erection, and no mechanism to determine who
requested the scaffolding and its intended use. Some scaffold requests lacked the
necessary detail and had to be sent back to the requester, and some requests were
constructed based only on blueprint or an individuals historical knowledge of the plant,
rather than on a walkdown. To rectify these weaknesses, closer scrutiny of the requests
was being made, requests that lacked the necessary information were returned to the
requester, walkdowns of the areas to verify the location and necessity were conducted
when determined necessary, and the ALARA group was screening requests. Although
the licensee had not quantified the dose cost as a result of the problems identified with
the scaffolding process, as an example they identified that scaffolding which was *
- installed for the 1201-01 inboard reactor water clean up system isolation valve work was
not necessary, and cost about 600 person-rem.
c.
Conclusions
Although there was no significant dose producing emergent work and rework during the
outage, work scope additions after the outage dose goals were established contributed
to some early accelerated outage work and associated dose. With the exception of
weaknesses associated with the scaffolding erection and removal program, the
planning, scheduling and implementation of the outage work process was sufficient.
R1 .2
ALARA Plan Implementation and Oversight of Radiological Work
a.
Inspection Scope (IP 83729)
The inspectors reviewed the effectiveness of the licensee's radiological controls, work
practices and oversight of radiological work activities, and efforts to reduce dose and
- implement the ALARA program for D2R15. The inspectors interviewed workers and
members of work control groups; reviewed ALARA action plans, radiation work permits
(RWPs) and applicable procedures; attended pre-job meetings; and observed ongoing
work in various areas of the plant.
4
b:
Observations and Findings
Work packages, ALARA plan implementation and the associated radiological controls
for the following jobs were reviewed by the inspectors:
Drywell main steam safety relief valve maintenance
Control rod drive system removal activities
Torus desludging and inspection
Various other drywell, reactor and turbine building activities
The inspectors noted good use of dose reduction techniques and ALARA and
engineering controls for the outage. Examples of ALARA and engineering controls
included hydrolyzing numerous piping systems, including the reactor building equipment
drain tank line around the torus catwalk; full scale under vessel mock up training for the
control rod drive and reactor head detensioning work; and establishment of hold poi11ts
for high dose risk work. Other examples of engineering controls included use of high
efficiency particulate air (HEPA) filtered temporary ventilation units at several work sites;
considerable use of remote monitoring equipment including use of cameras for the
drywell, condensate demineralizer, and refuel floor work; wireiess remote monitoring
equipment and teledosimetry during in vessel and other work; and extensive use of lead
shielding blankets, especially in the drywell.
Coordination and oversight of radiological work was provided by ALARA engineers
assigned to specified areas of the plant, and periodic or continuous radiation protection
technician (RPT) job coverage for high risk activities. ALARA engineers were assigned
to the drywell, reactor and turbine buildings, the refuel floor and balance of plant.
Inspector attendance at ALARA pre-job briefings disclosed that worker roles and
responsibilities were clearly discussed, rndiological information was appropriately
exchanged, and that good interaction between work groups and radiation protection
(RP) staff occurred. Inspector observation of control rod drive (CRD) removal activities,
a torus dive to conduct inspection work and the preparations for a dive in the reactor
cavity indicated good work oversight. The radiological controls for these evolutions were
implemented in accordance with the ALARA plans and applicable procedures. Although
overall radiological control of work activities was generally good, some weaknesses in
work coordination and oversight were noted. For example:
Coordination of work activities at the drywell control point was occasionally
unorganized, particularly when several work activities were to commence
concurrently. The inspectors noted that at times, drywell control point briefings
were conducted for multiple work groups simultaneously, creating congestion
and the potential for an inadequate exchange of radiological information during
the briefing.* Moreover, on March 23, 1998, no drywell coordinator was assigned
for the day shift, when the designated ALARA engineer did not report to work .
5
. v
On March 19, 1998, the licensee identified a five-fold increase in radiation levels
on a nozzle in the drywell, over six hours after the elevated levels were created
by the removal of insulation. Although the insulation removal work was known
by RP to have taken place and post removal surveys were planned, poor RPT
communications and job turnover, and inadequate work oversight caused the
surveys to be overlooked for several hours. While no work took place in the area
before the elevated dose rates were identified, the potential for unnecessary
worker dose existed. The problem was compounded when *post insulation
removal survey results were not verified, and the area was unnecessarily posted
and controlled as a locked high radiation area.
The *licensee recognized these problems and later modified the briefing process at the
drywell control point to eliminate congestion and enhance RP to work group
communication. RPT job turnover was also expanded to include an ALARA engineer or
RP supervisor in the turnover process.
c.
Conclusions
Radiological control of work activities was good with some exceptions related to
occasional drywell work coordination ~nd oversight problems. ALARA initiatives,
engineering controls and job planning were effectively implemented, and efforts to
control dose, prevent intake of radioactive material and limit personnel contamination
events were successful.
R4
Staff Knowledge and Performance in RP&C
R4.1.
Review of Radiation Worker Performance
a.
Inspection Scope (IP 83750/83729)
The inspectors reviewed the licensees initiatives to improve radiation worker (radworker)
practices during the D2R15 refueling outage. The inspectors observed work practices
at numerous work sites and in general throughout the station.
b.
Observations and Findings
Although several poor work practices were documented by the licensee and observed
by the resident NRC inspectors early during the outage, during this inspection, the
inspectors generally observed good radworker practices. It was also noted that
radworker practices were better than those observed by the inspectors during the
D3R14 refueling outage in 1997. Workers properly donned and removed protective
clothing and demonstrated a good knowledge of electronic dosimetry alarm set points,
awareness of radiological conditions, and appropriate use of low dose waiting areas.
Although there were some observations of persons loitering in elevated radiation fields
in the reactor building, especially near the entrance/exit area between Units 2 and 3 on
the main floor, there were no observations of loitering in the Unit 2 drywell or most other
6
"
job sites. While loitering in the reactor building improved later during the inspection,
isolated examples continued to be observed by the inspectors.
During this outage the licensee was aggressive in attempting to control craft worker
crew size, number of workers used to walk down jobs, and in controllin.g loitering. The
inspectors noted that at the drywell and other control points, the RP staff routinely
challenged workers and their supervisors concerning job location, knowledge of dose
rates .and crew size.
On March 18, 1998, the inspectors attended a safety meeting conducted by the craft
general supervisors and the ALARA supervisor, to discuss station ALARA expectations.
The ALARA supervisor emphasized the importance of controlling crew size, the need for
the judictous use of workers, and how effective controls in these areas impacted on
overall station dose. The ALARA coordinator also indicated that although coordination
and cooperation between the station and craft workers was generally good, better
cooperation was expected in order to achieve the ALARA goals. During that meeting,
the ALARA coordinator indicated that because of the station's high source term, the
station would continue to challenge the craft to limit crew size and to act aggressively to .
reduce dose. This was the first outage the general contractor worked at the Dresden
Station and consequently, they were not cognizant*of the stations high source term and
its signifitant effect on dose. Craft personnel indicated during the meeting that generally
the size and use of work groups was appropriate; however, they recognized that
improved efforts to meet ALARA goals were needed.
The licensee reestablished an around the clock greeter program, initiated originally
during an outage in late 1996. The intent of the greeter program was to improve ALARA
practices by ensuring workers were aware of radiological conditions in their respective
work areas. The greeters were positioned at the main access control to the
radiologically posted area (RPA) and quizzed workers regarding their planned activities,
the radiological work environment, and verified that required dosimetry and safety
equipment was worn. Observation of greeter activities indicated that workers were
routinely challenged by the greeters and that greeters were knowledgeable of their
responsibilities.
c.
Conclusions
. Radworker practices improved as the outage progressed and in general, radworker
practices improved compared to previous refueling outages. Initiatives such as the
greeter program, increased emphasis on worker responsibility, first line
supervisory oversight and stronger RP control point oversight, were instrumental in
reducing poor radw6rker practices. While the inspectors also noted that the station's
aggressive approach in challenging craft workers about crew size and knowledge of the
radiological work environment had some positive effect on contractor work control and
dose, continued emphasis in this area is warranted .
7
R4.2
Plant Walkdowns and Other Observations
a.
Inspection Scope (IP 83750)
The inspectors made frequent walkdowns of the radiologically posted areas (RPAs)
inside the power block, and visually assessed material condition, housekeeping and
radworker practices.
b.
Observations an~ Findings
The inspectors noted a number of hoses and cabling on the floor of the main level of the
drywell and the accumulation of other materials and equipment cluttering the area.
Additionally, during a drywell walkdown on March 23, 1998, the inspectors observed
water dripping onto the steel ladder leading up to the second level, and onto electrical
conduit trays. Although the licensee indicated that a catch basin diverting the water drip
from a known leaky valve was apparently mispositioned, it appeared that effective
corrective actions were not taken to better control the leak before the inspectors brought
the matter to the licensee's attention.
Radiological housekeeping in the reactor building was generally good, and workers used
appropriate contamination control practices such as securing hoses and other items that
crossed contamination area boundaries. During walkdowns, the inspectors noted. that
radioactive materials were appropriately labeled and controlled. High and locked high
radiation areas were posted and controlled in accordance with NRC requirements .
However, the inspectors noted inconsistency with some of the radiation area postings
between Unit 2 and 3 reactor buildings, and questioned the adequacy of certain Unit 2
radiation area postings. Specifically, some areas in the Unit 3 reactor building were
posted as "elevated dose rates - no loitering," while areas in Unit 2 with the same
general radiation fields did not have similar postings .. Also, radiation area postings did
not always clearly indicate the location of the radiation field, and postings were not
always appropriately positioned to alert workers approaching the area from all potential
ingress points. The inspectors further noted that the licensee had not yet developed
specific criterion for uniformly posting radiation areas with elevated dose-rates, although
the issue was identified to the licensee during the Unit 3 refueling outage in 1997. RP
management planned to review these matters at the conclusion of the Unit 3
maintenance outage in June 1998, and .develop guidelines to ensure posting
consistency and clarity. Independent inspector surveys verified that selected areas of
the drywell, reactor and turbine buildings were properly posted, and that results
coincided with the licensee's surveys.
8
..
c.
Conclusions
Radiological housekeeping and control and labeling of radioactive material was good in
most areas. However, housekeeping in certain areas of the drywell was poor, and a
water drip from a known leaky valve in the drywell was apparently not adequately
addressed until brought to the licensee's attention by the inspectors. While radiation
area posting discrepancies were noted in the reactor building, areas were posted and
controlled in accordance with NRC requirements.
RS
Staff Training and Qualifications in RP&C
a.
Inspection Scope (IP 83750/83729)
The inspectors interviewed contract radiation protection technicians (CRPTs) and RP
supervisors regarding the training and qualifications required for CRPTs working the
refueling outage.
b.
Observations and Findings
Prior to hiring CRPTs, RP supervision reviewed candidate resumes and contacted
previous employers of selected candidates to verify experience and references.
Industry standardized qualification criteria was established for senior and junior CRPTs.
,Training requirements for prospective CRPTs included successful completion of the
licensee's standardized core training at its Professional Training Center {PTC) within the
previous two years, and a minimum score of 80% on the standardized Northeast Utilities
Health Physics Theory Exam within the previous three years. As part of the on-the-job-
training process, CRPTs were required to demonstrate proficiency in conducting
radiation surveys, and successfully complete other task performance evaluations.
CRPTs were also required to complete station radiation protection and administrative
procedure training, and selected CRPTs completed task specific training related to diver
coverage, radioactive material shipping and the unconditional release program. Written
tests were administered and\\or task performance was demonstrated to verify that
procedure and task specific training was successfully completed. A matrix maintained
by the licensee documented key training and qualification information for each CRPT,
and was used by outage management to ensure that only qualified CRPTs were
assigned specified tasks. Video or hands-on mockup training was provided to those
workers involved in CRD removal\\replacement work, installation of temporary lead
shielding and certain reactor vessel. disassembly operations.
Inspector discussions with contract RP staff involved in outage activities indicated that
the training adequately prepared the workers for assigned tasks.
c.
Conclusions
The training of prospective contract RP staff was completed in accordance with station
procedures, and adequately prepared workers for assigned outage tasks .
9
R6.
RP&C Organization and Administration
a.
Inspection Scope (IP 83750/83729)
The inspectors reviewed the RP organization and the RP staffing plan for the refueling
outage, and recent changes made to the routine RP organization.
b.
Observations and Findings
In February 1998, the station's Radiation Protection Manager (RPM) accepted the Unit 1
Plant Manager position, and the assistant RPM was named acting RPM. The RPM and
assistant RPM had been in their positions for approximately two years and one year,
respectively. Additionally, just prior to the current refueling outage, the Lead RP
Operations Supervisor was relieved of that position and assi9ned as the technical
assistant to the acting RPM. Due to these organizational changes, the licensee
designated experienced RP and health physics (HP) personnel as shift HP Managers,
responsible for day and night shift outage execution, both reporting to the acting RPM.
The RP organization was augmented for the refueling outage by 98 contract RP
personnel, including nine contract ALARA engineers and 61 senior CRPTs. However,
within the first two weeks of the outage, the station lost twelve CRPTs, including eight
se_nior CRPTs. As a result, CRPT work hours were increased from 60 to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> per
week. RP management planned to continue the extended work hours for both station
and CRPTs until critical path work was completed. During the inspection, the licensee
was in the process of replacing the contract staff loses with RPTs from its sister stations.
Although approximately 12% of the CRPT staff was lost during the early phases of the
outage, adequate job coverage continued and the RP program was not significantly
impacted.
c.
Conclusions
Administration of the overall RP program during the first half of the planned 40-day
outage was generally good, and not adversely affected by the RP organization changes
made just prior to the outage, and the unexpected loss of several CRPTs early in the
outage.
RS
Miscellaneous RP&C Issues
R8.1
(Closed) Violation 50-237/95015-09: 50-249/95015-=09: An operations department
worker failed to ensure that the Unit 2 drywell gate was secured following egress from
the area. Corrective actions included disciplinary action for the involved worker, and
operations department tailgate training. Since no similar problems occurred since a
similar event in February 1996, it appears that the licensee's corrective actions were
effective. This item is closed.
R8.2
(Closed) Violation 50-237/97010-02: 50-249/97010-02: Failure to conduct an evaluation
of the radiological environment prior to conducting decontamination work in.the Unit 2
10
torus bays. The incident resulted in a small intake of radioactive material to one worker .
The inspectors noted that the corrective actions taken to prevent recurrence included a
review of the training program for high risk work (Station Procedure No. DAP 12-09) by
all station radiation protection shift supervisors; discussion of the event with all
decontamination laborers onsite; and training for decontamination laborers and laborer
supervisors. These corrective actions appear effective. This item is closed.
V. Management Meetings
XI
Exit Meeting Summary
The inspectors presented the preliminary inspection results to members of licensee
management orrMarch 24, 1998, and further discussed the inspection findings with the acting
RPM during a telecon on April 2 1998. The licensee acknowledged the findings presented and
did not identify any of the documents reviewed as proprietary .
11
PARTIAL LIST OF PERSONS CONTACTED
G. Abrell, Regulatory Assurance
L. Aldrich, Acting Radiation Protection Manager
C. Howland, Unit 1 Plant Manager
J. Kuczynski, Acting Technical Lead Health Physicist
W. Lipscomb, Site Vice President Assistant
W. Long, Scaffold Coordinator
D. Miller, Unit 1 Lead Radiation Protection Shift Supervisor
J. Moser, Lead Operational Health Physicist
P. O'Conner, Trades Project Superintendent
M. Pacilio, Station Outage Manager
P. Quealy, Unit i Health Physics Supervisor
C. Richards, Assessment Superintendent
P. Swafford, Station Manager
D. Winchester, Manager, Quality and Safety Assessment
Opened
None
Closed
INSPECTION PROCEDURES USED
Occupational Radiation Exposure
Occupational Radiation Exposure During Extended Outages
Follow up - Plant support
ITEMS OPENED AND CLOSED
50~237/95015-09
Failure to maintain a high radiation area in the drywell locked.
50-249/95015-09
50-237/97010-02
50-249/97010-02
Failure to condud an adequate evaluation, leading to an intake of
radioactive material.
12
'*
LIST OF ACRONYMS USED
A LARA
CRPT
Radworker
As-Low-As-ls-Reasonably-Achievable
Control Rod Drive
Contract Radiation Protection Technician
High Efficiency Particulate Air
Professional Training Center
Radiation Worker
Radiation Protection
RPA
RP&C
Radiologically Posted Area
Radiation Protection & Chemistry
Radiation Protection Technician
Radiation Work Permit
PARTIAL LIST OF DOCUMENTS REVIEWED
D2R 15 ALARA Outage Plan
Station Procedure
No. DRP 6210-01 (Rev 01)
Station Procedure
No. DAP 12-04 (Rev 29)
Station Procedure
No. DAP 18-04 (Rev 06)
Station Procedure
No. DAP 12-09 (Rev 14)
Station Procedure
No. DAP 18-04 (REV 06)
RWP No. 987201 (Rev 0)
and Associated ALARA Plan *
RWP No. 987119 (Rev 0)
and Associated ALARA Plan
RWP No. 987206 (Rev 0)
and associated ALARA Plan
RWP No. 987114 (Rev 0)
and Associated ALARA Plan
Radiation Protection Requirements For Divers Engaged in
Underwater Work
Control of Access to High Radiation Areas
Management of Planned Outages
Dresden Station ALARA Program
Management of Planned Outages
D2R15 Reactor Disassembly/Reassembly and Related
Activities
D2R15 Drywell CRD System Pull/Put Maintenance
Activities
D2R15 Torus Internals Activities
D2R15 Drywell Main Steam Safety, Electromatic and
Target Rock Valve Maintenance
13