ML19241B035

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Responds to NRC 790430 Ltr Re Violations Noted in IE Insp Repts 50-269/79-08,50-270/79-08 & 50-287/79-08.Corrective Actions:New Calibr Technique Has Been Approved & Space Efficiency Factors Determined for Swipe Detectors
ML19241B035
Person / Time
Site: Oconee  Duke Energy icon.png
Issue date: 05/24/1979
From: Parker W
DUKE POWER CO.
To: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19241B033 List:
References
NUDOCS 7907110579
Download: ML19241B035 (3)


Text

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DUKE Powen COMPANY

[ Powen Ucit.DINO 422 SocTn Cucucu STurer, CILAHLoTTr. N. C. 2e242 wiwau o ,*anca.sa.

May 24, 1979 T E. E *= C ai t. Am E A 704 Vetr Pat S' CENT 373-4083 St ra s. Paoovctica.

Mr. James P. O'Reilly, Director U. S. Nuclear Regulatory Commission .

Region II  :> r 101 Marietta Street, Suite 3100 ~

', 'y' Atlanta, Georgia 30303

7. m

-t o

?U T

Re: RII:DMM 50-269/79-8 -

50-270/79-8 c.n 50-287/79-8 c:e Dear Mr. O'Reilly.

With regard to Mr. J. T. Sutherland's letter of April 30, 1979, which transmitted IE Inspection Report 50-269/79-8, 50-270/79-8, 50-287/79-8, Duke Power Company does not consider the information to be proprietary.

Please find attached responses to the deviation item and the infraction item.

Very truly yours, 7William O. Parker, Jr.

0./ .

pgM RLG:ses Attachment 312 244 5

790110'77p 7

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i DUKE POWER COMFANY OCONEE NUCLEAR STATION Response to IE Inspection Report 50-269/79-8, 50-270/79-8, 50-287/79-8 INFRACTION Technical Specification 6.4.1 requires the station to be operated and maintained in accordance with approved procedures.

Contrary to the above, f om March 1978 through March 1979, the Ge (L1) efficiency calibrations were obtained using a procedure other than EP/0/B/1003/09, which had been approved.

RESPONSE

The GeLi detectors were calibrated using a new technique because the NBS radio-isotopes necessary for a complete GeLi aetector calibration were not cvailable.

An outside vendor was used to calibrate.. the GeLi detector in the Charlotte En-vironmental Lab and then this detector was used as a standard for the Duke system.

A procedure for system GeLi detector calibration was approved on March 6, 1979.

Sources have been requisitioned so that (1) the new technique for calibration can be verified and (2) procedure HP/0/B/1003/09 - Calibration Procedure for GeLi Detectors on the ND 6620 Multichannel Analyzer - an be used for calibra-tion. The equipment will be calibrated using HP/0/B/luuj/09 when the new sources are received. The calibration should be completed by July, 1979.

DEVIATION ANSI Standard N323-1978, Radiation Protection Instrumentation Test and Calibra-tion, Section 4.3.2 states, " Calibration shall be performed with a standard source of sources providing radiation fields similar to those in which the instrument will be used."

Contrary to the above, the licensee utilized a Sr source for calibration of a GM-counterusedforcountgggsmearscontaminatedwithradionuclideshavingmuch lower beta energies than Sr. This procedure may lead to underestimation of contamination levels.

RESPONSE, Immediate corrective action consisted of increasing the efficiency factors on all swipe counters (8-y) by a factor of three until the average beta energies could be determined and standards could be prepared for checking the ef ficiency f actors.

Swipe. were taken at several locations in the station to determine the radio-nuclide composition of the contamination present. The isotopes found were largely Co-58/60 and Cs-134/137 which have a weighted average beta energy of approximately 0.18 MeV. Since this energy is slightly greater than the averageNew beta energy for efficiency fac-Cs-134, Cs-134 was chosen to determine the efficiency factors.

tors were determined for all swipe detectors on March 20, 1979.

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. -2 The swipe counters were all calibrated with a Cs-134 source in a two-inch stainless steel planchet. Periodic swipe checks will be made to determine if the average beta energy has changed.

2A6 312