ML20203E700
| ML20203E700 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 02/18/1998 |
| From: | Hehl C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Cross J DUQUESNE LIGHT CO. |
| References | |
| 50-334-97-08, 50-334-97-8, 50-412-97-08, 50-412-97-8, EA-98-045, EA-98-45, NUDOCS 9802270111 | |
| Download: ML20203E700 (8) | |
See also: IR 05000334/1997008
Text
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February 18, 1998
EA No.: 98 045
Mr. J. E. Cross
President
Generation Group
. Duquesne Light Company
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Post Office Box 4
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Shippingport, Pennsylvania 15077
J8 JECT:
NRC INTEGRATED INSPECTION REPORT 50 334/97 08,50 412/97 08
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Dear Mr. Cross:
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The NRC has received your response dated January 9,1998, to NRC inspection report
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Nos. 50 334/97 08and 50 412/97 08. Concerning violation A, thank you for informing us
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of the corrective ** d preventive actions documented in your letter. These actions will be
examined during a future inspection of your licensed program.
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in your response you requested that the NRC withdraw violation B contained in the report
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-(item 50 334/97 08-05). After careful review of your submittel, we have concluded that
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_ your rationale and basis is inadequate to support withdrawing the violation for the
following reasons:
(1)
Your response stated, in part, that, *the method used for calibration of the Victoreen
(vendor) RMS follows vendor recommendations for performing periodic electronic
and radiation calibrations..." As indicated in Section R2.1 of our inspection report,
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the vendor instruction manual specifications for operating voltage specified an
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operating voltage range between 500 and 1400 volts. Contrary to this _
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specification, your organization established the operating voltage for the RM 1LW-
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104 (Unit 1 liquid waste effluent: Victoreen detector type 843 30) at 450 volts.
(2)-
Your response stated that ANSI N42.18 neither directs nor implies that the
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operating high voltage be set on a plateau. We disagree. Such a position is
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contrary to well established industry practices and fundamentals for radiation
detection instrument calibration. The commonly accepted industry guidance ANSI
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N42.18, Section 5.4.7.5 specifies the expected condition that operating voltage be
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established such that a 15% variation in opeisting voltage not cause more than a
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5% variation in detection capability. Your own calibration records (Attachments 1
and 2) clearly demonstrate that the esteblishment of operating voltage at 450 and
650 volts for the RM 1LW 104 and the RM 1RM 215A monitors, respectively,
permits a 15% variation in operating voltage to affect detection capability
- significantly, i.e., well beyond'a 5% variation.
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Mr. J. E. Cross
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(3)
Your ratior. ale to establish a different method does not 3ppear well conceived. You
stated that, "the primary disadvantages of using the detectorplateau method for
determining the photomultiplier tube operating high voltage is that the sensitivity of
each detector willbe different and the same detector inay have a different
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sensitivity after each calibration. This would result in recalculating detector
sensitivity after each calibration which could directly affect monitor alarm setpoints
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andinputs to telease calculations. " These f actors, v.hich you cite as
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' disadvantages,' provide the bas:s of why it is imperative to effectively establish
operating voltage r d determine individual detector sensitivity. Variations due to
aging and environmental conditions are expected over the operating life of the
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detector and other Instrument components. Accordingly, the principal purpose of
secondary calibration is to validate the detector efficiency obtained during primary
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calibration. Section 1.1.1 of your ODCM, describes the setpoint determination
method for Unit 1 effluent RMS. The ODCM requires that detector efficiency
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(cpml Cilml) be used to calculate alarm and high high alarm setpoints. However,
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by your methodology, detector efficiency would not be maintained in a acceptable
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range with any variation in operating high voltage.
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From our review, it is evident that your calibration methodology did not establish the
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operating voltago for these instruments in conformance with commonly accepted industry
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standards; and you provided no new information in support of the recognition or
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acceptability of any other calibration technique. This finding continues to constitute a
failure to establish inadequate procedures for calibration of radiation monitoring systems.
Accordingly, we find no basis to withdraw the violation, as originally cited. You are
required to respond to the violation, within 30 days of the date of this letter, in accordance
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with instructions previously provided. in your ret ponse, please confirm that 1RM 215A
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and RM 1LW 104 are in conformance with the detector efficiencies listed in vour ODCM,
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Table 1.1 la.
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Sincerely,
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Original Signed by:
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Charles W. Hehl, Director
Division of Reactor Projects
Docket Nos. 50 334;50 412
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Mr. J. E. Cross
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cc w/ encl:
~ Sushil C. Jain, Vice President, Nuclear Services
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R. LeGrand, Division Vice President, Nuclear Operations Group & Plant Manager
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- W. Kline, Manager, Nuclear Engineering Department
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B. Tulte, General Manager, Nuclear Operations Unit
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M. Perger, Acting Manager, Quality Services Unit
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J. Arias, Director, Safety & Licensing Department
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J. MacDonald, Manager, System and Performance Engineering
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cc w\\cy of Licensee's Response:
M. Clancy, Mayor
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Commonwealth of Pennsylvania
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State of Ohio
State of West Virginia
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Mr. J. E. Cross
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DJaidbutlort w/cy of Licensee Response:
Region 1 Docket Room (with concurrences)
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PUBLIC
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Nuclear Safety information Center (NSIC)
NRC Resident inspector
H. Miller, RA/W. Axelson, DRA
N. Perry, DRP
D. Haverhamp, DRP
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A. Linde, DRP
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J. Lieberman, OE
T. Walker, ORA
B. McCabe, OEDO
R. Correia, NRR
F. Talbot, NRR
DOCDESK
inspection Program Branch, NRR (IPAS)
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DOCUMENT NAME: G:\\ BRANCH 7\\BV9708. REP
T) resolve e copy of this document. Indicate in the box:
- C" = Copy without ettschment/ enclosure
'E' = Copy with attachment / enclosure
- 8fa = No
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0FFICIAL RECORD COPY
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ATTACHMENT I
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DUQUESNE LIGHT COMPANY
RTL # A9.655J
Beaver VP.!Iey Power Station
HP Form 4.5.11.1
12/1994
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COUNTER CAllBRATION RECORD-Plateau Plot Data
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SOURCE DATA
INSTRUMENT DATA
COUNTING DATA
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Isotope:
Ba-133
Type:
( M-LW-10d/ Counted By:_
Radiation Type:
Gamma
Sorial No.:
N/A
Badge #: 4.L Zr Dkte: I 25 V 7
Accountability
Probe Type:
843-30
Count Time:
/u.
Number:
442
Serial No.:
200
Plateau Determination
Plateau Check
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Voltage
Bkg opm
Grosa cpm
Not cpm
% CHANGE
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400
360
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450
380
220290
225910
132.8
500
380
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550
480
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DUQUESNE LIGHT COMPANY.
RTL # A9.65SJ
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Beaver Valley Power Station
HP Form 4.5.11.2
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12/1994
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COUNTER CAUBRATION RECORD-Plateau Plot Grash
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SOURCE DATA
INSTRUMENT DATA
COUNTING DATA
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Isotope:
Ba-133
Type:
g M-LW-10J Counted By: VW/
Radiation Type:
Gamma
Serial No.:
N/A
Badge #: A#i L @ ate:4 .Ef 't 7
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Accountability
Probe Type:
843-30
Count Time:
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Number:
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Serial No.:
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ATTACHMENT 2
DUQUESNE LIGHT COMPANY
RTL # A9.655J
Beaver Valley Power Station
HP Form 4.5.11.1
12/1994
Q.OUNTER CAllBRATION RECORD-Plateau Plot Data
SOURCE DATA'
INSTRUMENT DATA
COUNTING DATA
Isotope:
Type:
RM-215A
Counted By: A.C_a3(el1:
Radiation Type:
Beta
Serial No.:
Badge #: 2iGL Date: eu-^
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Accountability
Probe Typ6:
843-20A
Count Time:
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Number:
166
Serial No.:
N/A
Plateau Determination
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Voltage
Skg epm
Gross cpm
Net cpm
% CHANGE
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Operating Voltage:
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Date: C
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Reviewed By:
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DUQUESNE LIGHT COMPANY
RTL # A9.655J
Beaver Valley Power Station
HP Form 4.5.11.2
12/1994
COUNTER CAUBRATION RECORD-Plateau Plot Graoh
SOURCE DATA'
INSTRUMENT DATJ
COUNTING DATA
isotope:
Type:
RM-215A
Counted By: d , (1, k I (1
Radiation Type:
Beta
Serial No.:
N/A
Badge #: 1I6 B Date: ' tu %
Accountability
Probe Type:
-843-20A
Count Time:
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Number:
166
Serial No.:
N/A
Gross cpm
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VOLTAGE
Reviewed By:
Badge #: [29 \\
Date: 0
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Be er V.fley Power St. tion
$nippingport. P A 15077 0004
RONALD L LeGR AND
(412) 39NE22
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2."Se*,."l"'.'*."n'a'ei.niu.n..,
Januay 9. WM
U. S. Nuclear Regulatory Commission
Attention: Document Control Desk
Washington, DC 20555-0001
Subject:
Beaver Valley Power Station, Unit No. I and No. 2
BV-1 Docket No. 50-334, License No. DPR-66
HV-2 Docket No. 50-412, License No. NPF-73
Integrated Inspection Report 50-334/97-08 and 50-412/97-08
Reply to Notice of Violation
In response to NRC correspondence dated Novemoer 26,1997, and in accordance
with 10 CFR 2.201, the attached reply addresses the Notice of Violation transmitted with
the subject inspection report.
An extension of the due date of the response until
January 9,1998, was requested of the NRC staff on December 24,1997.
Duquesne Light has performed a detailed review of the circumstances surrounding
alleged Violation B.
Based on the details provided in the attached response to this
violation, Duquesne Light respectfully requests that this violation be withdrawn.
If there are any questions concerning this response, please contact Mr. J. Arias at
(412) 393-5203.
Sincerely,
,{~ .,a ,/,' w/ fi
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Ronald L. LeGrand
Attachment
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Mr. D. S. Brinkman, Sr. Project Manager
Mr. P. W. Eselgroth, Chief, Reactor Projects Branch No. 7, Region I
Mr. D. M. Kern, Sr. Resident Inspector
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AhMMihn:NRG Region 1 Administrator
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DUQUESNE LIGHT COMPANY
Neclear Power Division
Beaver Valley Power Station, Unit Nos. I and 2
Reniv to Notice of Violation
Integrated Inspection Report 50-334/97-08 and 50-412/97-08
Letter Dated November 26,1997
VIOLATION A (Severity Level IV, Supplement IV)
Description of Violation (50-334/97 08-04)
Unit 1 Technical Specification (TS) 6.8.1.a requires that, " Written procedures shall be
established, implemented, and maintained covering...the applicable procedures
recommended in Appendix "A" of Regulatory Guide 1.33, Revision 2, February 1978,"
which includes radiation protection procedures. This requirement is partially
implemented by the site Health Physics Manual, which requires in Chapter 1, Part II,
Section E.2.g, that individuals shall comply with the provisions of their radiological work
permit (RWP) and any supplementary posted material for work in the radiologically
controlled area (RCA). Alllicensee RWPs require the user to review the radiological
conditions of their work area by reviewing the posted area survey maps.
Contrary to the above, workers were fotr
during the period of October 6-8,1997, in the
radiologically controlled areas (prima;y auxiliary and containment buildings), who had
not reviewed their survey maps prior to entry and were unaware of the radiological
conditions in their work and travel areas in the RCA.
Reason for the Violation
The primary cause of the violation is that management did not develop and communicate
adequate standards to ensure compliance. A review of site procedures determined that
there was a lack of specific guidance to be provided to workers regarding requirements
for knowledge of radiological conditions in low dose rate travel areas. A secondary cause
was that workers were complacent or had a lack of concern about their dose and the dose
rates in low dose rate areas. This is partially attributed to the lack of adequate standards.
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Reply to Notice of Violation
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NRC Integrated Inspection 50-334/97-08 and 50-412/97-08
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Page 2
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Corrective Actions Taken and the Results Achieved
The following were immediate corrective actions, some of which are interim and will be
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discontinued when other corrective actions are completed that will provide a similar level
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of compliance. These actions ensured workers were aware of the radiological conditions
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in their work and travel areas.
Developed and issued a Standard of the Week for two consecutive weeks that
included the expectation that workers are responsible to be knowledgeable of the
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radiological conditions of their work and travel areas.
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Instituted interim direct verbal worker briefings at strategic Radiologically Controlled
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Area (RCA) entry points. These briefings informed workers of the radiological
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conditions in their work and travel areas and included the location of any applicable
ALARA low dose waiting areas.
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Com.aunicated details of the deficiency and the revised interim controls to station
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managers and requested they achieve compliance from all individuals under their
cognizance.
- Added a supplement to radiation worker training that included management
expectations that workers are responsible to be knowledgeable of the radiological
conditions in their work and travel paths.
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The following corrective actions were taken in addition to the immediate corrective
actions listed above:
Revised the responsibilitu for Health Physics updating of posted survey maps to
ensure more timely and efficient updating.
Upgraded and simp}ified the posted survey maps at the entrances to RCAs to make
them easier for the worker to read and understand.
. Issued a letter to Health Physics personnel describing the c'orrective actions taken and
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those planned to be taken to address the deficiency.
' Issued a letter from the Plant Manager to station radiation workers reinforcing
management expectations of worker responsibilities with regard to their knowledge of
radiological conditions in their work and travel areas.
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- Reply to Notice of Violation
NRC Integrated Inspection 50-334/97-08 and 50-412/97-08
- Page 3
- Corrective Actions to Prevent Further Violations
- The following additional corrective actions will be implemented:
Incorporate additional management expectations for worker knowledge of radiological
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conditions in their work and travel areas into radiation worker training. This will be
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- completed by January 31,1998.
Revise Health Physics Manual (HPM) procedures to describe the methods to be
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followed to ensure timely posting and updating of survey maps. The HPM will also
be revised to describe the requirements for the workers to familiarize themselves with
the radiological conditions in their work and travel areas. These will be completed by
February 28,1998.
)
Provide workers retuming for the next refueling outage (2R07), that are not required
to receive radiation worker requalification training, information about management
expectations regarding worker knowledge of radiological conditions in their work and
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travel areas. This will be completed by the start date for 2R07.
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Conduct e.n effectiveness review of the corrective actions throughout the first half of
1998, inclusive of 2R07 completion. This will be completed by June 30,1998.
Date When Full Comoliance Was Achieved
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With the institution of the direct verbal worker briefimgs at strategic RCA enny points,
full compliance was achieved.
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Reply to Notice of Violation
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-NRC Integrated Inspection 50-334/97-08 and 50-412/97-08
Page 4
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VIOLATION B (Severity Level IV, Supplement IV)
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Descriotion of Violation (50-334/97-08-05)
Unit' l Technical Specification (TS) 6,8.'t.a requires that, " Written procedures be
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established, implemented and maintained covering...the applicable procedures
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recommended in Appendix "A" of Regulatory Guide 1.33, Revision 2, February 1978,"
which includes procedures for radiation monitoring system (RMS) operation.
Contrary to the above, the licensee failed to establish adequate RMS calibration
instructions in regard to determining RMS operating high voltage. Specifically, operating
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high voltage was not established on a plateau for RM-lRM-215A (Unit 1 Containment
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Particulate) and RM-ILW-104 (Unit 1 Liquid Waste Effluent). This was contrary to
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vendor manual "Victorcen Installation, Operation, and Maintenance, lastruction Manual
Beta Scintillation Detectors Models 843-20,843-20A, and 843-20B" and "Victorcen
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Instructional Manual Gamma Scintillation Detector Model 843-30" respectively; and was
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contrary to RMS calibration standards and industry guidance documents.
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Discussion of the Allened Violation
Duquesne Light Company (DLC) has evaluated the alleged violation and the related
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discussion in NRC Inspection Report 50-334/97-08 & 50-412/97-08 and does not concur
with the violation. The method used for calibration of the Victoreen (vendor) Radiation
Monitoring System (RMS) follows vendor recommendations for performing periodic
electronic and radiation calibrations of the monitors, and utilizes approved site specific
Maintenance Surveillance Procedures and Health Physics Manual procedures. These
procedures use a calibration method described in the vendor's system manual which was
provided with the purchase of the Beaver Valley Power Station (BVPS) Unit 1 Radiation
- Monitoring System (RMS). The site calibration procedures have incorporated vendor .
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improvements in the method for maintaining source geometry during calibration of the
units since the initial issue of vendor's system manual. DLC has obtained written
confirmation from the vendor that use of the calibration method provided with the system
manual including the use of the standard geometry fixture is correct.
With regard to the specific vendor manuals cited in the _ violation (Victoreen Installation,
,
Operation, and Maintenance, Instruction Manual Beta Scintillation Detectors Models
- 843-20, 843-20A, and 843-20B and Victorcen Instructional Manual Camma Scintillation
Detector Model 843-30), DLC has obtained written confirmation trc.n the vendor that the
- manuals are intended for general use, where detector is typically used for detection of a -
single isotope.1This is not the case for a process radiation monitor, where the detection
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Reply to Notice of Violation
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NRC Integrated Inspection '0-334/97-08 and 50-412/97-08
-Page5
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and measurement ofisotopes with characteristic decay energies from 80 Kev to 3 Mev
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are required. This is the detecticn range for the BVPS Unit 1 RMS.
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The violation refers to "RMS calibration standards," which apparently refers to the
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inspection report reference to ANSI N42.18. DLC has reviewed this document and
concludes that this standard neither directs nor implies that the operating high voltage be -
set on a plateau. Specifically, DLC has concluded that ANSI N42.18, Section 5.4.7.5,
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" Power Requirements" under Standards of Performance, is intended to address the effects
on instrument accuracy ofline voltage and frequency variations; not operating high
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voltage variations. Also, this section appears to be directly related to a previous section
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in the standard under Specification of Performance,5.3.2.4.2, Power Variations, which
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addresses line voltage.
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The violation also refers to " industry guidance documents," which apparently refers to
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the discussion of EPRI TR-102644 in the inspection report. DLC perfonned a search of
applicable regulations and NRC guidance documents and could not locate any NRC
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endorsement of this document. Likewise, DLC has not endorsed this document in its
RMS calibration pro:,edures.
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In addition, an independent third party evaluation of the alleged violation was performed
at the request of DLC. This evaluation assessed the calibration methodology used at
BVPS and concluded that the specific count rate method of calibration is acceptable and
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that setting the voltage on a plateau for scintillation detectors using photomultiplier tubes
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is unnecessary,
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in conclusion, RMS calibrations are performed in accordance with vendor
recommendations and technical documentation, and applicable regulations using
approved site specific procedures. Based on the above discussion, DLC respectfully
requests that the violation be withdrawn.
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Discussion of Radiation Monitor System Calibration Method
~ DLC performed a detailed review of the methods used for calibrating the BVPS radiation
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monitoring systems in an effort to ensure that the current practice used at BVPS is
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correct. The following discussion summarizes this review is being provided as additicaal
information.
The process and effluent RMS is calibrated to measure the concentration of radioactive
isotopes over a wide energy range (80 Kev to 3 Mev). Calibration methods developed .
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and recommended by the vendor and used at BVPS standardizes the response of the RMS
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. scintillation detectors in a manner that provides traceability to the original detection
geometry primary isotopic calibration. The method used, as described by the vendor, is
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called the " Specific Count Rate Method"(SCRM). The vendor acknowledges that there
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Reply to Notice of Violation
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' NRC Integrated Inspection 50-334/97 08 and 50-412/97 08
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are two additional methods that can be employed to establish a phot'omultiplier tube
(PMT) operating point for scintillation detectors, " Detector Plateau Method" and
" Specific Pulse Height Method."- However, the vendor did not and does not recommend
the use of either of these methods for the calibration of the BVPS Unit 1 RMS.
The SCRM recommended by the vendor requires setting the low discriminator to a
standardized value ' The detector is then placed in a specific geometry and exposed to a
reference transfer source traceable to the primary calibration. The PMT high voltage is
then varied until a specific count rate is produced from the detector. Additional sources
of different energies are then used to verify the energy response linearity and the source
strength linearity of the detector. This method is similar to the " Detector Plateau .
>
'
Method," but with the added feature of using a specific count rate to select the operating
high voltage and eliminating the ambiguity associated with selecting an operating high
voltage from a plateau. The primary benefit of using the SCRM is that all detectors in the
same geometry will have the same gain, or sensitivity and "as-found" and "as-left"
analysis may be performed as part of the calibration, to demonstrate the detector was
operating properly since the last calibration.
The primary disadvantages of using the " Detector Plateau Method" for determining the
PMT operating high voltage is that the sensitivity of each detector will be different and
,
the same detector may have a different sensitivity after each calibration. This would
result in recalculating detector sensitivity after each calibration which could directly
affect monitor alarm setpoints and inputs to release calculations. Setting the operating
high voltage on a plateau would minimize count rate changes due to voltage drift or PMT
gain changes above or below the selected operating high voltage. However, for a non-
'
monenergetic application (gross activity detection), such as that desired in a nuclear
,
power plant, selection of an operating high voltage based on a plateau would not ensure
the low energy response of the system.
As noted in the inspection report, a small change in operating high voltage could result in
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a significant change in output count rate. However, in consultation with the vendor, any
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such changes would be readily apparent in the nominal monitor readings. Also, as noted
in the inspection repon, performance of the BVPS Unit 1 RMS with respect to high
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- voltage based on "as-found" and "as-left" data indicate that the high voltage power
supplies are highly stable and that typically there is little if any high voltage drift.
'
In summary, during factory primary calibrations, the vendor did not and does not attempt
to find a plateau and does not select PMTs to obtain specific response characteristics.
. Because of the variables involved in calibrating scintillation detectors to operate over a
,
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. wide energy range, selection of an operating high voltage using the " Specific Count Rate
.
Method" permits not utilizing generation and use of plateau data.
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