ML19322B613
| ML19322B613 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 04/30/1976 |
| From: | Parker W DUKE POWER CO. |
| To: | |
| References | |
| NUDOCS 7912040639 | |
| Download: ML19322B613 (2) | |
Text
'
q DUKE POWER COMPANY q
~~/
Powen Bustatwa a_,
w 4aa SocTn Caulcu SruzzT, CHARLoTTz, N. C. aca4a w s LLI AM O. PA R et C R. J R.
WCE PetSicth?
TELEM*QNC; ARCA 704 Sf tau Pacouctione 375 4083 April 30, 1976 Mr. Norman C. Moseley, Director U. S. Nuclear Regulatory Commission Suite 818 230 Peachtree Street, Northwest Atlanta, Georgia 30303 Re: Oconee Nuclear Station Docket Nos. 50-269, -270, -287
Dear Mr. Moseley:
Pursuant to the requirements of Oconee Nuclear Station Technical Specification 6.6.2.2.c & d, this report is submitted describing a condition in which a measured level of radioactivity exceeded the control level by greater than ten times and describing conditions in which measured levels of radioactivity exceeded the control levels by greater than four times, but less than ten times.
On April 27, 1976, analytical results of water samples collected on a monthly frequency from March 2, 1976 through March 31, 1976 were reviewed..
Given below is a summary of the pertinent results of the radioactivity concentration of these samples.
All are surface samples and, except for one monthly composite sample as noted, all are grab samples.
Sample Location Date Collected uCi/ml 000.3 Bridge North 03/02/76 Cs-137 < 6.9E-9 of site (Control)
Gross Beta (0.0 1 6.3)E-9 I-131 (0.0 1 6.2)E-11 Co-58 < 8.2E-9 000.7 Hwy. 183 Bridge 03/02/76 Cs-137 (4.6 1 1.1)E-8 Co-58 (2.7 1 0.2)E-7 Gross Beta (1.9 1 0.1)E-7 I-131 (1.2 1 0.1)E-8 000.7 Hwy. 183 Bridge 03/31/76 Co-58 (3.8 t 1.0)E-8
-(Monthly Composite)
Gross Beta (6.7 1 0.9)E-8 I-131 (4.1 10.2)E-8
..,....-.e..
- ~ - - + - -
-~~--*e
- " " - -- ' * ~
4 lig/Istman LCTJishly April 30, 1976 9
~
.r,g n 005.2 Hwy. 27 Bridge 03/02/76 Co-58 (3.5 i 1.3)E-8 Gross Beta (6.1 10.9)E-8 I-131 (5.2 1 0.2)E-9 013, 5.8 Miles South 03/02/76 Gross Beta (2.4 1 0.7)E-8 of Keowee Dam I-131 (5.8 1 0.8)E-8 Radioactivity concentrations in the water samples collected are dependent upon the corrosion and fission product concentration in liquid effluents.
For the period of January through March 1976, 4.88 curies of corrosion and fission products were released from the station in liquid effluents.
For this period, 6
the maximum tailrace concentration was 2.83 x 10 uCi/ml, and the average was 8
1.43 x 10 uCi/ml. Of this 4.88 curies released, 1.293 curies was Iodine-131, representing 27 percent of the total activity The maximum tailrace concentration y
Of Iodine-g31 during this period was 7.5 x 10 pCi/ml, and the average was 3.79 x 10 uCi/ml.
From sample data, it can be seen that these results are between the maximum and average calculated concentrations as would be expected.
The station's annual objective (Technical Specification 3.9) in making effluent releases is to maintain the annual average concentration of corrosion and fission products in 11guid effluents upon release from the Restricted Area 8
to no more than 2 x 10 Ci/ml.
10CFR20,jppendixB,TableII, Column 2,allowsanannualaverageconcentration i
of 3 x 10 Ci/ml which the Oconee Technical Specifications specify as an instantaneous release limit.
Although the instantaneous release limit was exceeded, releases are well within the objective annual average concentration values.
These concentrations are high due to the previousl,' reported error in the method for calculating effluent release rates as disclosed in Reportable Occurrence R0-269/76-4, April 21, 1976.
The method for calculating effluent release rates has been corrected.
In the future, the concentrations of radioactivity in surface water samples should level off or decrease due to this correction.
Very truly yours, William O. Parker, Jr.
EDB:mmb
_.