ML20155G223
| ML20155G223 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 04/24/1986 |
| From: | Taylor J DAIRYLAND POWER COOPERATIVE |
| To: | Zwolinski J Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.F.1, TASK-TM LAC-11563, NUDOCS 8605050093 | |
| Download: ML20155G223 (2) | |
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D DA/RYLAND h
[k COOPERAT/VE eo Box 817 2615 EAST AV SOUTH L A CROSSE WISCONSIN StFI)1 (0081 788 4000 April 24, 198G In reply, please refer to LAC-ll563 DOCKET NO. 50-409 Mr. John Zwolinski, Director BhR Project Directorate #1 Division of BWR Licensing U. S. Nuclear Regulatory Cosumission Washington, DC 20555
SUBJECT:
DAIRYLAND POWER COOPERATIVE LA CROSSE BOILING WATER REACTOR (LACBhR)
PROVISIONAL OPERATING LICENSE NO. DPR-45 ADDITIONAL REQUEST FOR EXEMPTION FROM NUREG-0737, ITEM II.F.1. ATTACINENT 1. TABLE II. F.1-1. DISPLAY
References:
- 2) DPC Letter, Linder to Zwolinskt
_.AC-10783, dated April 28, 1985
- 3) DPC Letter. Linder to Diggs, LAC-10848, dated May 9, 1985
- 4) Eberline Letter, Beard to P. Shafer, Response to LAC-8412, dated August 19, 1982
- 5) DPC Letter, Linder to Crutchfield, LAC-7930, dated November 18, 1981
- 6) DPC Letter, Linder to Crutchfield, LAC-7180, dated October 10, 1980
- 7) NRC Letter, W. Shafer to Taylor, I&E Inspection Report 86-003 (DRSS), dated March 28, 1986 8) 10 CFR 170.12
Dear Mr. Zwolinrki:
As indicated in' our previous correspondence to you (References 1 and 2), we requested an exemption from NUREG-0737 Item II.F.1 for the upper range of noble gas concentration. According to NUREG-0737. Item II.F.1, Attachment 1 Table II.F.1-1, the display shall be " continuous and recording as equivalent Xe-133 concentrations, or uCi/cc of actual noble gases."
Our letter (Reference 6) indicated that we were investigating the application of an Eberline SPING-4 to continuously monitor post-accident elevated stack noble gas releases.
The SPING-4 was installed in January 1981 (Reference 5).
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Mr. John Zwolinski, Chief April 24, 1986 5, Operating Reactors Branch No. 5 LAC-Il563 U. S. Nuclear Regulatory Commission page 2 The SPING-4 continuously monitors a sample of the stack gaseous releases and has a printer for recording data. However, the mid-range and high range noble gas channels read out in terms of gamma-Becquerel-MeV per cubic centimeter, instead of uCi/cc or Xe-133 equivalent. The SPING series noble gas instrumentation was originally calibrated to Xe-133 and Kr-85.
The SPING's mid-range and high range noble gas detectors are energy compensated Geiger Mueller tubes, and the monitoring system is incapable of directly converting the gamma-Bq-MeV/cc readings into uCi/cc or Bq/cc.
A knowledge of the isotopic mix and gamma-energy emitted per uCi or Bq of each isotope is required to convert this reading to concentration (Reference 4). This task can be handled by a larger " Report Generating" computer or by empirically derived conversion graphs and factors based upon expected post-accident noble gas mixtures at varying times after the reactor achieves subcriticality (Reference 4).
Currently, the latter method is used by our staff to convert indicated gamma-Bq,MeV/cc readings into approximate uCi/cc values.
The GM measurement is relatively flat with gamma-energy emissions per unit volume (gamma-Bq-MeV/ce), and the reading could be used directly along with release flow and atmospheric diffusion to calculate an approximate offsite dose rate (Reference 4).
Conversion factors for SPING indicated gamma-Bq-MeV/cc to uCi/cc are found in two LACBWR procedures, EPP-5 and Operating Manual Volume 10, Section 5.4.2.6.2(5) and Figure 5.2.
The procedural conversion from gamma-Bq-MeV to approximate uCi/cc, and subsequently Ci/sec, should meet the criteria of NUREG-0737, Item II.F.1, Attachment 1. Section 4(b), which states, "The design description shall include... description of procedures or calculational methods to be used for converting instrument readings to release rates per unit time, based on exhaust air flow and considering radionuclide spectrum distribution as a function of time of shutdown."
In this respect, we request an exemption from the requirement of NUREG-0737, Item II.F.1, Attachment 1 Table II.F.1-1 (Display).
As required by Reference 8, payment for this request for exemption from NUREG-0737, Item II.F.1 should be adequately addressed by Reference 3.
If you have any additional questions, please contact us.
Very truly yours, DAIRYLAND T COOPERATIVE C_
b c,q amesg. Taylor, Genera anager W
g JWT:PWS:dh cc - J. G. Keppler, Reg. Admin., NRC-DRO III NRC Resident Inspector J. Stang, Project Manager PC4-4