ML20203E700

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Ack Receipt of 980109 Response Re Insp Rept 50-334/97-08 & 50-412/97-08 & Nov.Licensee Request for Withdrawal of Violation B Has Been Denied.Response to Violations Required within 30 Days of Date of Ltr
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)
v • d • e


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 i

Post Office Box 4 j

Shippingport, Pennsylvania 15077

J8 JECT: NRC INTEGRATED INSPECTION REPORT 50 334/97 08,50 412/97 08

NOTICE OF VIOLATION l

Dear Mr. Cross: l

!

The NRC has received your response dated January 9,1998, to NRC inspection report  !

Nos. 50 334/97 08and 50 412/97 08. Concerning violation A, thank you for informing us I

of the corrective ** d preventive actions documented in your letter. These actions will be  ;

examined during a future inspection of your licensed program.  :

,

in your response you requested that the NRC withdraw violation B contained in the report j

-(item 50 334/97 08-05). After careful review of your submittel, we have concluded that l

_ 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, t

t. 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-  !

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 -

operating high voltage be set on a plateau. We disagree. Such a position is ,

contrary to well established industry practices and fundamentals for radiation

detection instrument calibration. The commonly accepted industry guidance ANSI .

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

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 2 1

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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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j sensitivity after each calibration. This would result in recalculating detector

sensitivity after each calibration which could directly affect monitor alarm setpoints

i andinputs to telease calculations. " These f actors, v.hich you cite as  ;

j ' 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 i

detector and other Instrument components. Accordingly, the principal purpose of

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secondary calibration is to validate the detector efficiency obtained during primary

calibration. Section 1.1.1 of your ODCM, describes the setpoint determination

4 method for Unit 1 effluent RMS. The ODCM requires that detector efficiency

- (cpml Cilml) be used to calculate alarm and high high alarm setpoints. However,

. by your methodology, detector efficiency would not be maintained in a acceptable

l 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

! operating voltago for these instruments in conformance with commonly accepted industry

i standards; and you provided no new information in support of the recognition or

l 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

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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,

! Table 1.1 la.

4

Sincerely,

! Original Signed by:

i Charles W. Hehl, Director

Division of Reactor Projects

Docket Nos. 50 334;50 412

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- _ . _ _ _ _ _ _ . _ _ - _ . _ _ _ . , _ _ . _ . _ . - . _ . _ _ ~ ~ . . _ . ~ _ _ _ . _ _ _ . . . _ _ _ . _ _ . _ _ . _ , _ _ _ . _ . , _ . . _ _ _ . . . _ _ . _ . _ _ ,

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Mr. J. E. Cross 3 l

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cc w/ encl:  ;

~ Sushil C. Jain, Vice President, Nuclear Services i

R. LeGrand, Division Vice President, Nuclear Operations Group & Plant Manager j

- W. Kline, Manager, Nuclear Engineering Department l

B. Tulte, General Manager, Nuclear Operations Unit i

M. Perger, Acting Manager, Quality Services Unit  !

J. Arias, Director, Safety & Licensing Department i

J. MacDonald, Manager, System and Performance Engineering l

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cc w\cy of Licensee's Response:

M. Clancy, Mayor  !

.

Commonwealth of Pennsylvania ,

State of Ohio

State of West Virginia

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Mr. J. E. Cross 4

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DJaidbutlort w/cy of Licensee Response:

Region 1 Docket Room (with concurrences) ,

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PUBLIC '

Nuclear Safety information Center (NSIC)

NRC Resident inspector

H. Miller, RA/W. Axelson, DRA

N. Perry, DRP

D. Haverhamp, DRP

'

A. Linde, DRP i

J. Stolz, PDI 2, NRR  :

D. Brinkman, PM, PDl 2, NRR  !

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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OFFICE Rl/DRP 1 R 1fML I Rl/ORyJd l Rl/ $P , I I I

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J@lle'~ DHolodf/ - CHsW # #

DATE Mtit/.9Br/n/rr 02/ I /98 02/ G /98 02/ /f'/98 02/ /98

0FFICIAL RECORD COPY

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ATTACHMENT I

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l DUQUESNE LIGHT COMPANY RTL # A9.655J

Beaver VP.!Iey Power Station HP Form 4.5.11.1

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12/1994

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COUNTER CAllBRATION RECORD-Plateau Plot Data

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I SOURCE DATA INSTRUMENT DATA COUNTING DATA  !

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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Grosa cpm Not cpm % CHANGE i

Voltage Bkg opm

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400 360 97390 97030 XXXXXXXX

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450 380 220290 225910 132.8

500 380 267606 26,7226 18.3 i

j 550 480 418584 418104 56.5

600 560 422228 421668 0.9

. 650 500 424530 424030 0.6

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Operating Voltage: __

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DUQUESNE LIGHT COMPANY. RTL # A9.65SJ

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Beaver Valley Power Station HP Form 4.5.11.2

, l 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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4 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

Accountability Probe Type: 843-30 Count Time: / m,J

Number: 442 Serial No.: 200 Gross epm

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VOLTAGE

Reviewed By: Badge #: h Date: /23/0 7

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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: Cs-137 Type: RM-215A Counted By: A.C_a3(el1:

Radiation Type: Beta Serial No.: ' '

_... Badge #: 2iGL Date: eu-^ .

Accountability Probe Typ6: 843-20A Count Time: / r.d

Number: -

166 Serial No.: N/A Plateau Determination

/ Plateau Check

Voltage Skg epm Gross cpm Net cpm % CHANGE

550 0 114 114 )O000000(

600 0 4304 4304 3675.4

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650 20 20058 20038 365.6

700 20 35944 35924 79.3

750 20 44846 44826 24.8

800 40 46310 46270 3.2

850 00 47254 47174 2.0

900 220 48516 48296 2.4

Operating Voltage:

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Reviewed By: N Badge #: /d#f \ Date: C 7[f&

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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: Cs-137 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: le

Number: 166 Serial No.: N/A Gross cpm

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VOLTAGE

Reviewed By: Badge #: [29 \ Date: 0 Y 94

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  • Be er V.fley Power St. tion

$nippingport. P A 15077 0004

RONALD L LeGR AND (412) 39NE22

2."Se*,."l"'.'*."n'a'ei.niu.n.., Januay 9. WM **"*

L-98-003

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/ ,ofi

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Ronald L. LeGrand  !

Attachment

c: Mr. D. S. Brinkman, Sr. Project Manager

Mr. P. W. Eselgroth, Chief, Reactor Projects Branch No. 7, Region I l

Mr. D. M. Kern, Sr. Resident Inspector j

AhMMihn:NRG Region 1 Administrator y

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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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j/ Reply to Notice of Violation

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NRC Integrated Inspection 50-334/97-08 and 50-412/97-08

Page 2

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l Corrective Actions Taken and the Results Achieved

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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

of compliance. These actions ensured workers were aware of the radiological conditions

[ 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. ,

-* 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

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

L 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

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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

! conditions in their work and travel areas into radiation worker training. This will be -

- completed by January 31,1998.

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  • Revise Health Physics Manual (HPM) procedures to describe the methods to be

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

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to receive radiation worker requalification training, information about management

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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.

  • 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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-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)

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Unit' l Technical Specification (TS) 6,8.'t.a requires that, " Written procedures be

established, implemented and maintained covering...the applicable procedures ,

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 l

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  ;

vendor manual "Victorcen Installation, Operation, and Maintenance, lastruction Manual

Beta Scintillation Detectors Models 843-20,843-20A, and 843-20B" and "Victorcen

! Instructional Manual Gamma Scintillation Detector Model 843-30" respectively; and was ,

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 . '

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

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

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,

" Power Requirements" under Standards of Performance, is intended to address the effects

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- on instrument accuracy ofline voltage and frequency variations; not operating high

i. voltage variations. Also, this section appears to be directly related to a previous section

in the standard under Specification of Performance,5.3.2.4.2, Power Variations, which a

addresses line voltage.

l The violation also refers to " industry guidance documents," which apparently refers to

l the discussion of EPRI TR-102644 in the inspection report. DLC perfonned a search of

i applicable regulations and NRC guidance documents and could not locate any NRC

endorsement of this document. Likewise, DLC has not endorsed this document in its

RMS calibration pro:,edures.

! 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

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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,

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

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requests that the violation be withdrawn.

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

! 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

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isotopes over a wide energy range (80 Kev to 3 Mev). Calibration methods developed .

and recommended by the vendor and used at BVPS standardizes the response of the RMS

E . 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 ,

' NRC Integrated Inspection 50-334/97 08 and 50-412/97 08

Page 6

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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 .

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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

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gain changes above or below the selected operating high voltage. However, for a non-

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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

j a significant change in output count rate. However, in consultation with the vendor, any

l such changes would be readily apparent in the nominal monitor readings. Also, as noted

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in the inspection repon, performance of the BVPS Unit 1 RMS with respect to high

- 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.

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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.

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. 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

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Method" permits not utilizing generation and use of plateau data.

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