ML19281A277
| ML19281A277 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 02/28/1979 |
| From: | Counsil W CONNECTICUT YANKEE ATOMIC POWER CO. |
| To: | Grimes B Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19281A279 | List: |
| References | |
| NUDOCS 7903090276 | |
| Download: ML19281A277 (2) | |
Text
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CONNECTICUT YANKEE AT O M I C POWER COMPANY BERLIN. CONNECTICUT P O BOX 270 HARTFOND CONN ECTICUT 06tOI L
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203 666 6911 February 28, 1979 Docket No. 50-213 Mr. Brian K. Grimes Assistant Director for Engineering and Projects Division of Operating Reactors U.
S. Nuclear Regulatory Commission Washington, D. C.
20555
Reference:
(1)
W. G. Counsil letter to B.
K. Grimes dated January 18, 1979.
Gentlemen:
lbddam Neck Plant Radiological Ef fluents Technical Specifications By Reference (1), Connecticut Yankee Atomic Power Company (CYAPCO) proposed a license amendment to incorporate Radiological Ef fluent Technical Specifications into Appendix A of its operating license No. DPR-61.
In addition, revisions to Appendix B and the Of fsite Dose Calculation Manual (ODCM) were also provided.
Subsequent to the date of Reference (1), CYAPCO has performed a more detailed review of the ODCM.
Section 5.3.1 of NUREG-0133, Requirements for Implementing 10CFR Part 50, gives guir'ance on calculating quarterly doses due to gaseous effluents.
The models given include the use of annual average X/Q's for these quarterly dose calculations.
This guidance was utilized in the initial writing of the Haddam Neck ODCM.
While reviewing this guidance and the ODCM, it was determined that the use of annual average X/Q's would be inappropriate in some cases.
This is a result of seasonal variations in predominant wind direction and stability.
For example, during the summer months, the wind may blow predominantly in a par-ticular direction, yet very infrequently in that direction during the remainder of the year.
Thus, the third quarter X/Q may be significantly greater than the annual average X/Q.
Assuming that a third quarter dose calculation using annual average X/Q's yields a result of 2 mrad, the detailed calculation re-quired for the semi-annual effluent report, using real time meteoro'_ogy, may yield a result of 8 mrad.
This would exceed the allowable quarterly limit, yet would not have been identified by the surveillance required t o ensure this limit is met.
OMop6
. Since real time meteorology is logistically impractical for use on a monthly basis, the suggested model change reflects the use of maximum quarterly average X/Q observed during three years of data, rather than the maximum annual average X/Q.
The revised pages of the ODCM required to implement this change are provided as Attachment 1.
Because the Attachment updates the information provided in Reference (1), the fee forwarded pursuant to 10CFR170 with Reference (1) is applicable to this instance. Accordingly, no payment is enclosed.
Very truly yours, CONNECTICUT YANKEE ATOMIC POWER COMPANY f
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W. G. Counsil Vice President Attachment