ML20246N417
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| ML20246N417 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 07/12/1989 |
| From: | Durr J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Corbin McNeil PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| References | |
| NUDOCS 8907190367 | |
| Download: ML20246N417 (2) | |
See also: IR 05000352/1989080
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-JUL 12' 1989
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- Docket.Nos; 50-352.-
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, ;50.-353
' Philadelphia Electric Company.
' ATTN: Mr. C. ~ A. McNeill', ~Jr.
. Executive Vice' President
Nuclear- - !-
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. Correspondence ~ Control Desk
P. O. Box.7520' ,.
Philadelphia, PA. 19101-
Gentlemen:
-Subject: Combined Inspection 50-352/89-80 and 50-353/89-80
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This: refers to your letter dated May 8,1989,:in response to our = letter
dated March 23, 1989
'Thank'you for.'qforrring es of'the corrective and preventive. actions' documented
in your letter' . Those setions will be examined during a~ future inspection of-
.your licensed program.
;Your cooperation with us is appreciated.
Sincerely,
. Original Signed BY8
P. K. Eopen
Jacque P. Durr, Chief
. Engineering ' Branch
Division of Reactor. Safety.
.cc,w/ enc 1:
J. S. Kemper,'Sr., Senior Vice President - Nuclear Construction
G. _M. Leitch, Vice President - Limerick Generating Station
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S. J. Kowalski, Vice' President - Nuclear Enginee' ring
.
D. R. Helwig, General Manager - Nuclear Servcies
M. J. McCormick, Jr.,: Manager - Limerick Generating Station
W.' T. Ullrich, Manager . Limerick Unit 2 Startup
A. S~. MacAinsh, Manager '- Limerick Quality Division
l0 G. A Hunger, Jr. , Director - Licensing Section l T. B. Conner, Jr. , Esquire
E. J. Bradley, Esquire, Assistant General Counsel
H..D. Honan,-Branch Head -~ Nuclear Engineering Licensing
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.
Public Document Room (PDR)
l Local Public Document Room (LPDR) L Nuclear Safety Information Center (NSIC)
NRC Resident' Inspector
Commonwealth of Pennsylvania
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: PHILADELPHIA ELECTRIC COMPANY
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LIMERICK GENERATING ST ATION
j. P. O. BOX A
SAN ATOG A. PENNSYLVANIA A 19464
(215) 3271200 sat. 2000
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M. J. M cCO M MIC K. 'J a.. P.E.
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6 .-3.fl'.".'.."l."$*.".m... 'May 8, 1989 -
Docket Nos. 50-352
o
50-353
License No. NPF-39
Construction Permit No. CPPR-107
U.S. Nuclear Regulatory Commission
ATTN: Document Control Desk
-Washington, D.C. 20555
SUBJECT: Limerick denerating Station,-Units 1 and 2
Response:to Observed Weaknesses Noted in
Special Maintenance. Team Inspection
Report No. 50-352/89-80, 50-353/89-80
NRC letter dated March 23, 1989, transmitted Special
Maintenance: Team Inspection Report No. 50-352/89-80, 50-353/89-80
for the Limerick Generating Station, Units 1.and 2. .This letter
also requested that we address the noted weaknesses contained in
the report and outlined in Appendix 3.- The letter requested a
written response within.45 days to the noted items. Attached to
this letter is our-response to each observed weakness.
If you have any questions or require additional
information, please do not hesitate to contact us.
Very truly yours,
Ql 41 0
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M. V. McCormick, Jr.
Plant Manager
DBN: kap
Attachment
cc: W. T. Russell, Administrator, Region I, USNRC
T. J. Kenny, USNRC Senior Resident Inspector
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Attachment 1
Page 1 of 11
NRC Inspection Report
50-352/89-80
50-353/89-80
Item 1
NRC Observed Weakness
Communications with offrite engineering organizations could be
improved (Ref. II.4.1 {pg. 12}).
Response
Regarding the general issue of communications between the
station and the offsite engineering organization, an update to the
response provided to NRC Inspection Report 50-352/88-20 is provided
below.
-The Engineering Work Request (EWR) process, implemented at
Limerick in 1989 has provided engineering support for station
requests in such areas as Licensee Event Reports (LERs), Equipment
Qualification (EQ) evaluations, potential deportability and
operability evaluations, and specific design related questions. The
EWR process is being tracked and trended along with the !
Non-Conformance Report (NCR) and Engineering Review Request Form
(ERRF) processes using the Nuclear Engineering Task Tracking (NETT)
system. Over 600 individual Limerick requests have been responded
to by Engineering between January and April 1989.
The status of the tracking and trending is reported monthly in
the Senior Management Report (SMR) and includes information
regarding timeliness of responses, total requests processed and the
current backlog of requests. This report is discussed monchly with
the nuclear group vice-presidents and their direct reports.
Six deu cated engineering personnel have been located onsite and
additional engineering resources are located at the
Architect / Engineer's (A/E's) Pottstown, Pennsylvania office. An i
Engineering project management staff, located at the site, {
coordinates and tracks each individual request using the NETT j
process and ensures effective communications between the station and ]
the offsite engineering organizations. Members of the staff attend j
the daily routine plant meetings (e.g. morning meeting, TRIPOD, j
PORC) and provide needed support. Our goal is to locate i
approximately ten individuals from the engineering organization at I
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the site by the end of December 1989.
The station engineering personnel have been trained on how to
properly complete an EWR to ensure that station requests for
engineering support clearly identify needs and expectations. This
will help provide effective use of the EWR thereby,providing
effective communications. l
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, Attachment 1
Page 2 of 11
NRC Inspection Report .
50-352/89-80 .
50-353/89-80 )
o i l l . Periodic meetings between station and engineering management 1 !
were held on a bi-weekly basis during the outage and are presently !
scheduled to continue to be held on a monthly basis after the 1
outage. These meetings have been effective in prioritizing and j
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resolving problems which require engineering support.
Potentially reportable issues identified by the offsite i
engineering organization are communicated to the station regulatory
personnel by way of a Deportability Evaluation Form (REF). Station .
management can then evaluate the need for compensatory or other
required actions, to make any required notifications, and to request
additional engineering support utilizing the EWR process. This
mechanism has provided effective communications between the offsite l 1
engineering organization and station personnel such that potential
deportability / equipment operability concerns are raised to station !
operations personnel in a timely manner. !
Some examples of recent effective engineering support and
com.nunication between the offsite engineering organization and
station personnel especially in the area of maintenance include 1)
investigation and evaluation of the jet pump riser nozzle crack and
design of modifications to install crack monitoring equipment, 2)
development of the test procedure and design of the required
modifications for the main turbine torsional testing, 3)
investigation and evaluation of indications on the Low Pressure
Turbine blades, 4) design of a modification to relocate the
Suppression Pool Temperature Monitoring System (SPTMS) temperature
probes, 5) the project task force which is reviewing and resolving
problems identified during the review of the 10CFR50 Appendix R
related fire protection issues, and 6) the establishment of periodic
Service Water System Reliability Group meetings involving
engineering and station personnel.
In conclusion there is clear evidence that there are improved
communications between the offsite engineering organizations and the
station staff.
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Attachment 1
Page 3 of 11
NRC Inspection Report
50-352/89-80
50-353/89-80
Item 2
NRC Observed Weakness: .
The operability of the HPCI room unit coolers was a concern in
view of the ESW piping corrosion and no periodic performance test
for these coolers. (Ref. II.4.2 (pg. 14})
Response
During the Unit 1 Second Refueling Outage the NRC inspector
observed several activities related to Emergency Service Water (ESW)
system valve and pipe replacements including the High Pressure
Coolant Injection (HPCI) system room unit cooler supply piping.
This planned modification work was-being done to increase supply
piping sizes to several ESW components to allow for aging
degradation of this piping. During this pipe replacement,
significant pipe corrosion was observed in the removed piping. The
NRC inspector questioned the future operability of the HPCI room
unit coolers in light of the observed corrosion.
4
During the pipe replacement work, pipe friction coefficients
were estimated and incorporated into a computerized ESW system flow
network model. Engineering and the Architect / Engineer analyzed the
ESW model using the new data and new piping sizes and determined
that a successful two unit ESW flow balance could be achieved.
The two unit flow balances were performed during the Unit 1
Second Refueling / Unit 2 Tie-In Outage and proved ESW is capable of
providing adequate flows to all components in both units including
the HPCI room coolers for all six acceptance criteria modes. An
additional mode proved both ESW loops could independently support
eight diesel generators while providing the required' flows to both
units' safety related heat exchangers.
To ensure the ESW system will continue to meet its required
demands and support operability, several actions have been and will
be taken. A solution to the general ESW piping corrosion issue is
described under item 3 of this attachment. Quarterly flow balancing
of the ESW system will be performed and piping and components will ,
be periodically inspected. In addition, the Technical Specification
required quarterly ESW pump performance test will be performed and
pump capacity performance will be monit: red and evaluated. A
further description of the quarterly flow balancing and component
inspection program is described below.
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. . Attachment 1-
Page-4 of 11
NRC Inspection Report
-50-352/86-80
50-353/89-80
Routine ESW flow balances tests RT-1-Oll-251-0 and
RT-1-011-252-0 will be performed quarterly. The procedures were
based on the flow balances performed as part of the two unit flow '
balance test program. They have beenspecifically-designed to
closely monitor ESW components with marginal performances observed
in'the two unit flow balance test program. .-Every quarter, potential
' problem' components will be tested. Included in this category.will
be all Residual Heat Removal (RHR) system. pump seal coolers, RHR
motor oil coolers, the Unit 1 HPCI room coolers, and the Unit 2
Reactor Core Isolation Cooling (RCIC) system room coolers. These
. components are more'likely to become ' problem' components because of
their piping configurations. The remaining components will be
tested a minimum of once during each cycle as part of the scheduled
. quarterly tests. Acoustic flow monitors will be used to verify the
accuracy of the procedure. Acoustic flow testing will be performed
on any component with unusually high differential pressure (DP)
readings and on coolers with a past history of fouling. This
redundant verification will ensure that we maintain a close watch on
potential problems.
Every refueling outage, Maintenance will perform visual
inspections of ESW and Service Water pipe and components via the
Preventive. Maintenance Program. Once again, ESW components
identified to have a. potential problem such as RHR seal coolers,
Unit'l HPCI room coolers.and Unit 2 RCIC room coolers will be
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inspected each refueling outage. In addition, any component that
experienced poor performance in the quarterly flow balances will be
inspected. The piping associated with the inspected coolers will
also be inspected. Flow balances will establish a constant
reference point of ESW flow versus total system dynamic head. Each
quarter this will be compared with past results and the data
obtained will be used to monitor pipe fouling. Low DP readings on
heat exchangers during the flow balances could also indicate low
flow conditions due to flow restrictions. The computerized ESW
system flow network model will be utilized in the ESW monitoring
program. The monitoring program will enable us to predict system
performance and potential problems. The monitoring program will be
continually evaluated and modified as necessary to ensure continued
system operability.
Item 3
NRC Observed Weakness: l
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A comprehensive solution to the ESW piping corrosion issue was
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not yet well defined. (Ref. II.4.2 {pg. 15})
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Attachment 1
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.Page 5 of 11
NRC Inspection Report
50-352/89-80 ,
50-353/89-80
Response
Based.on observations of service. water system components prior
to-commercialfoperation of Unit 1, a service water / circulating water
(cooling tower) chemical treatment program was developed. The
program was developed to limit corrosion, deposition and
microbiological fouling in circulating water, service water.and
portions of ESW. This treatment system was installed and made
operational shortly after commercial' operation (after receipt of the
required NPDES permit from the Pennsylvania Department of
Environmental Resources). Provisions for corrosion rate monitoring,
using corrosion coupons, were included in the scope of this
installation. It was recognized that, although reductions in
corrosion rates were expected, further corrosion protection could.be
achieved with clean pipe surfaces. We therefore began to
investigate cleaning alternatives in parallel with instituting the
corrosion treatment program and periodically monitoring the
effectiveness of the program using the corrosion coupons, an
instantaneous corrosion monitor, and individual component
inspections (conducted as components are isolated and opened due to
maintenance activities).
Due to the amount of piping involved in these systems, and the
isolation / availability constraints and outage schedule limitations
associated with mechanical cleaning, chemical cleaning techniques
.were pursued. A chemical cleaning technique was identified and
. testing was' conducted, using samples of service water piping removed
from Limerick. Although this two step chemical cleaning process
(deposit softening followed by mild acid wash) was demonstrated to
be effective in a similar application at another utility, it was not
effective in removing Limerick's deposits. Investigations into
chemical cleaning techniques continued into cycle 2 for Unit 1. An
alternate cleaning program has been identified similar to the
previously_ tested two step program, which based on recent successful
application in a similar application has proven effective. We plan
to test this program using ESW piping samples removed during the
second Refueling Outage.
In addition, during a design review prior to the Unit 1 First
Refueling Outage, we recognized that due to normal aging (corrosion
degradation) of the pipe, there would not be sufficient system flows j
to support 2 unit operations and some ESW supply piping would need '
to be replaced. During the First Refueling Outage, sections of
piping in the 'A' loop of ESW were replaced with larger diameter
piping. Inspection and testing of the piping replaced during this
outage indicated that a corrosion problem existed in small ESW
lines, specifically the one-inch diameter piping to the RHR pump
seal coolers and RER motor oil coolers, but was not evident in the
larger diameter piping inspected or replaced.
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Attachment 1
Page 6 of 11
NRC Inspection Report
50-352/89-80
50-353/89-80
During the Second Refueling Outage, secticns of piping of the
'B' loop of ESW were replaced for the aging concern described above.
The new piping was passivated with a high concentration of corrosion
inhibition chemicals prior to wetting. Passivation is a chemical
treatment applied to the inner metal surface of the piping to
inhibit corrosion. The removed sections of pipe contain similar
amounts of corrosion as contained in the 'A' loop piping removed 18
months earlier with the exception of the HPCI room unit cooler
piping. The 'A' loop piping replaced during the first refueling
outage was inspected and found to contain a very small amount of
corrosion after 18 months of service. Evaluation of the corrosion
monitoring data and the observations made during the second
Refueling Outage indicate that the corrosion rate within the ESW
piping has been reduced. Samples of the deposits obtained from the
ESW piping were analyzed and the results indicate that the fouling
problem is caused by general iron corrosion products and not from
silt / mud deposition, microbiological fouling or microbiological 1y
influenced corrosion.
Based upon the chemical analysis results, ESW system
inspections, and several tests involving the service water system
(which normally supplies the ESW piping and components), we have
determined the causes of the ESW system fouling to be the following:
'l . Ineffective layup practices during plant construction and
testing phase which resulted in prolonged periods of exposure
of the piping to raw water in stagnant or intermittent flow
conditions. This resulted in high corrosion rates and
deposition / accumulation of the corrosion products on the pipe
surface.
2. An effective cleaning program was not identified and
implemented coincident with the chemical treatment program.
This limited the effecti"oness of the chemical treatment.
3. Although the cooling tower corrosion treatment program does l
provide some corrosion protection of ESW, isolation of )
certain ESW components and low or intermittent flow '
conditions when in standby mode further limit this
protection.
Chemical treatment of the service water and ESW systems has been
recently upgraded to provide enhanced dispersant and anti-corrosion
chemicals. Initial results of this upgraded treatment program
indicate even lower corrosion rates than achieved during the !
previous treatment program. A study is in progress to determine the ;
feasibility of a targeted biocide and corrosion inhibitor program to !
address the corrosion problems during stagnant / intermittent !
operating conditions present in the ESW and Residual Heat Removal l
Service Water (RHRSW) systems. A Service Water System Reliability
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Attachment 1
Page 7 of.ll
NRC Inspection' Report
50-352/89-80
50-353/89-80
Group, composed of onsite and offsite engineering and technical
: personnel, was initiated in December,-1988, to identify and address
specific Service Water and ESW problems.
. These actions will provide the comprehensive solution to the ESW
piping corrosion issue.
Item 4
NRC Observed Weakness:
Deletion of QC witness points in certain maintenance procedures
without specific guidance (Ref. II.4.4 {pg. 18}).
Response::
The weakness identified as the process for deleting QC witness
points =was recognized by NQA during the NRC inspection and
appropriate 1 corrective measures were taken at that time. As stated
in the Inspection Report, the problem stemmed from the efforts to
increase accountability for quality at the worker level and sharpen
the focus of QC on the more critical aspects of the work activities.
Without formal guidance to accomplish this, QC witness points were
inconsistently applied and, in some instances, appropriate QC
witness points had been deleted from certain procedures along with
those that were. unnecessary. During the NRC inspection, a~ review
was initiated by the QC Division which determined that of
approximately 700 Maintenance Procedures, seventy-seven (77) were
revised without the specific guidance being in place. These seventy
seven procedures were reviewed and eleven (11) required revision to
reinstate the appropriate QC witness points which were inadvertently
deleted. The eleven procedures including the emergency diesel;
engine and motor control center preventive maintenance procedures
identified by the NRC inspector were appropriately revised prior to
performance of any work activities utilizing them. i
As committed to during the inspection, formal guidance for
y determining QC points for specific work activities has been l proceduralized. Maintenance Guideline No. 28, titled
" Identification of Quality Control Witness Points" and a supplement
to the QC Inspection Program Procedure, Supplement NQA-4-SlA,
" Determination of QC Action Points", provide the formal guidance to
the maintenance procedure writer and QC procedure reviewer for
determining when QC witness points are to be included in the
electrical and mechanical preventive maintenance procedures.
Supplement NOA-4-SlA is expected to be formally issued by June 30,
1989.
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Attachment'1
Page 8 of 11
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NRC Inspection Report
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50-352/89-80
50-353/89-80-
' Item-5'
NRC Observed Weakness: F
Low' Level-QA/QC involvement in the ESW piping corrosion issue.
(Ref. .II.4.4 {pg. 19))
. Response
The ESW piping system corrosion problem had been previously
identified during flow balancing of the ESW system during
pre-operational testing. A flow network analysis was performed-to.
aid in flow balancing and modifications were initiated to ensure.
that no unacceptable flow restrictions existed as the ESW piping
aged. . These modifications were identified and substantiated by
written Safety Evaluations and Plant Operating Review Committee
revi'ews.
During the course of on going ESW piping modifications, QC-
inspection personnel questioned the acceptability of the ESW piping
corrosion.
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However, in the absence of specific cleanliness .
acceptance criteria in the governing specification, and in light'of
the on-going. modifications, flow network ' analysis -and engineering
study, NQA management ' and QC supervision felt that the ESW corrosion'
problem was adequately identified and controlled and concluded that
it was not necessary to issue nonconformance reports..
In order to avoid recurrence in situations where the involvement
of the' appropriate personnel would not be as evident, supplement to
NOA-QC inspection procedures are being developed to more clearly.
define' cleanliness acceptance' criteria for plant operating systems.
These crite ia sill include loss of cross-sectional area that could
impair or pronibit mechanical piping system components.such as' check
! valves, coolers or heat exchangers from performing their. intended
function. The supplemental inspection procedures are expected to be
issued by. June 2, 1989. These criteria will be used to determine
the acceptability of internal cleanliness conditions.of plant piping
systems and if not met will be the basis for issuance of Equipment
Trouble Tags (ETT's) or Nonconformance Reports (NCR's) in accordance
with procedure NOA-24 " Control of Hardware Non-Conformances" (now
NGAP NA-03N001).
In addition, a committee has been appointed by the NOA-General
Manager to revise NOA-24 (NGAP NA-03N001) to ensure that ambiguity
will not exist in the procedure regarding nonconforming conditions
and the issuance of NCR's. The procedure revision is expected to be
completed by September 30, 1989.
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Attachment 1
Page 9 of 11
NRC Inspection Report
50-352/89-80
50-353/89-80
These, or any other nonconformances that are found to be
repetitive, shall be considered a significant nonconformance in
accordance NQA-24. As such, a Corrective Action Request shall_be
initiated to management attention in accordance with existing
procedure NOA-25, " Corrective Actions," to request a root cause
analysis and to determine corrective action to prevent recurrence.
Item 6
NRC Observed Weakness:
The lack of preparation of a Maintenance Procedure to support
lapping operations for D/G crankshaft bearings. (Ref. III.S.0 {pg.
25}).
Response:
The need for a bearing journal lapping procedure was previously
identified during the construction phase of Limerick Unit 2.
Bearing inspections were scheduled to be performed on all four Unit
1 emergency diesel generators (D/G's) during the Unit 1 second
refueling outage and during this inspection, journal lapping is not
normally required. In addition, there were no vibration problems
indicating that the journal bearings would need replacing and
journal lapping was not expected to be necessary during the second
refueling outage. Therefore, incorporation of journal lapping
instructions into permanent procedures was determined to be of a
lower priority than revision and enhancement of other procedures
required to support the Unit 1 Refuel Outage. During the overhaul
of the D12 D/G, journal lapping was identified to be required arid a
lapping procedure was generated shortly thereafter.
Journal lapping instructions are expected to be incorporated
into the appropriate permanent Maintenance Procedure (s) prior to
July 31, 1989.
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Item 7
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NRC Observed Weakness: l
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Slow implementation of the PRA into the prioritization of )
maintenance work. (Ref. III.5.0 (pg. 27J) '
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Attachment 1
Page 10 of 11 3
NRC Inspection Report
50-352/89-80 1
50-353/89-80 j
Response:
Several factors inhibited early extensive use of the
Probabilistic Risk Assignment (PRA) in the maintenance process and
at Limerick in general. These included:
1) The lack of a comprehensive, living PRA that reflected the
as-built plant, and,
2) The lack of a user friendly PRA tool that would simplify and
expedite use of the.PRA.
The following describes actions taken over the past few years to
eliminate these factors:
1) The PRA originally performed in 1980 was reviewed during the
plant licensing process and updated in September 1982. Before
widespread use could be made of the PRA, the system models had
to be revised to reflect as-built designs. Also, station
operating procedures, that were non-existent in 1982, had to be
incorporated. The PRA was updated in August 1986 to reflect
Unit 1 as-built design and most of the emergency operating
procedures (i.e. the Transient Response Implementation Plan
(TRID) procedures). A second update was completed in November
1988 tict completed the incorporation of the TRIP procedures and
reflected two unit operation. Completion of this update
addresses the first factor providing Limerick with a
comprehensive, living PRA that reflects the as-built plant and
supports applications.
2) PRA applications in the past were limited due to the available
computer software that was difficult and cumbersome to use. In
1987, the Nuclear Engineering Department PRA Branch purchased a
personal computer (PC) workstation that streamlined the process
of modifying and using the PRA. The conversion of the PRA to
the workstation model was completed by November 1988. The PRA
work station was used to develop the PRA parameters (i.e. what
systems and equipment are PRA important and how they affect Core
Damage Frequency) to be utilized by the station PRA programs and
will be used by engineering to answer specific PRA based
questions from the station. The PRA workstation addresses the
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second factor; it is the tool that was needed to simplify PRA
use and provide better responsiveness to PRA requests.
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Attachment 1
Page 11 of 11
NRC Inspection Report
50-352/89-80
50-353/89-80
With the above described improvements completed in November of
3988, Limerick has been able to develop several programs involving
the PRA. Specific to the prioritization of maintenance work, these
programs include Administrative Guidelines (AG) AG-42, "PRA
Applications in Plant Maintenance" and AG-43, " Guideline for the
Performance of System Outages." Following extensive training of
Limerick personnel, these programs became effective in January 1989
and have since then been implemented.
Item 8
NRC Observed Weakness:
The lack of adherence to an administrative procedure (A-26) resulted
in traceability problems of mechanical tools. (Ref. III.7.0 {pg.
36))
Response:
This problem had been identified prior to the inspection and the
Maintenance Request Form (MRF) had been changed in late 1988 to
allow recording of up to 15 tools versus 5 allowed on the old form.
On February 9, 1989, the next day following identification of the
problem by the NRC inspector, a meeting was held with the
maintenance department personnel. The importance of recording all
tools used during maintenance activities on the MRF was stressed in
the meeting. Continuing training for Maintenance personnel will
address the need to include calibrated tool serial numbers on the
MRF in order to provide traceability.
A review of all out of tolerance (OOT) tools is being performed.
Prior to January 1, 1988, Quality Assurance (QA) personnel recorded
all calibrated tools used on sa'.'ety related equipment in parallel to
the work activity. A similar traceability problem is net likely to
have occurred prior to January 1, 1988 nor after the meeting held on
February 9, 1989 and therefore the review will encompass the OOT
reports from the calibration facility received from January 1, 1988
to February 15, 1989. This review will compare the OOT tool
reports, the tool usage log and the referenced MRF's to ensure that
the OOT tools are properly identified on the MRF and that the affect
of the OOT tools have been evaluated. This review includes the nine
MRF's identified during the NRC inspection. Any deficiencies
identified during this review will be evaluated and corrected. In
addition, a maintenance guideline is being prepared for the control
of calibrated tools. All corrective actions are expected to be
completed by September 1, 1989.
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