ML20003H359

Ro:On 810406 & 13,gamma Analyses of Weekly Milk Samples in Environ Radiological Monitoring Program Detected Excessive Cs-137 Activity.Cause Unknown.Extra Samples Being Taken. Summary of Releases,Environ Samples & Dose Projections Encl

ML20003H359
Person / Time
Site:	Brunswick
Issue date:	04/23/1981
From:	Dietz C CAROLINA POWER & LIGHT CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
BSEP-81-0869, BSEP-81-869, NUDOCS 8105050659
Download: ML20003H359 (3)

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Carolina Power & Light Company

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% .:l3 Brunswick Steam Electric Plant P. O. Box 10429 Southport, NC 28461 April 23,1981 FILE: B09-13516.2 SERIAL: BSEP/81-0869 Mr. James P. O'Reilly, Director U. S. Nuclear Regulatory Commission Region II, Suite 3100 101 Marietta Street N.W.

Atlanta, GA 30303 BRUNSWICK STEAM ELECTRIC PLA).T, UNIT NCS.1 & 2 LICENSE NOS. DPR-71 and DPR-62 DOCKET NOS. 50-325 and 50-324

'30-DAY NONROUTINE RADIOLOGICAL ENVIRONMENTAL EVENT REPORT

Dear Mr. O'Reilly:

Results of gamma analyses of weekly milk samples collected on April 6, 1981 and April 13, 1981, as part of Brunswick Steam Electric Plants Environmental Radiological Monitoring Program detected Cs-137 at concentration.s of 2481 7 pCi/l and 179 i 6 pCi/l respectively, at tilk sampling Station No. 35. The analysis on the sample of April 6,1981, wa completed on April 13, 1981. The analysis for April 13, 1981, was completed on April 16, 1981. Station No. 37 (control station) revealed Cs-137 activity on the March monthly composite of 9.04 i 4.12 pCi/l and an activity of <6.6 pCi/1 (MDA) on sample taken on April 13, 1981. The Cs-137 activity in these samples constitutes a 30-day reportable event in accordance with Brunswick Technical Specifications, A:, . dix B, "

Section 5.4.2b, pertinent to environmental sampling. ,

The source of this Cs-137 activity is unknown at this time. In our preopera-tional environmental sampling program we had unexplained high levels of Cs-137 in the milk of this cow. A summary of plant releases, environmental sampling data, and dose projections are included in an attachment to this report.

Extra samples ara being taken at and around this station in an effort to determine the source of this Cs-137 activity and will be included in a follow-up report.

Very truly yours, Y\

C. R. Dietz, General Manager Brunswick Steam Electric Plant AHC/mcg Attachment (OS3 cc: Mr. R. A. Hartfield jierV.Stello,Jr. ff 8105050659

EFFLUENT AND ENVIRONMEhTAL DATA

1. Unit Nos.1 and 2 Stack and Vent Release Data, Cs-137 February 1981 3.99 x 10" Ci March 1981 1.12 x 10" Ci

-6 March 31 - April 6,1981 1.496 x 10 Ci

2. Milk Sa=ple Results (Cs-137 Concentrations in pCi/1)

Sample Date Station No. 35 Station No. 37 February 1981 36.414.8 <MDA March 1981 105 1 5 9.0414.12 April 6,1981 24817 April 13, 1981 17916 <6.6 pCi/1 (<MDA)

The samples for the month of February and March are monthly composite gamma scans. The sampics for April 6,1981 and Ar .11 13,1981, were checked due to the high Cs-137 levels found in the March composite sample.

3. Fodder and Feed (pasture grass)

? April 6, 1981 Station No. 35 Isotope Activity in pCi/gm dry l

Zr-95 1. 2 t .12 Nb 95 2.081 08 Ru 103 .324 i .084 Cs-137 .0516 i *.0715 (<MDA)

Ce-141 .364 1 106 Ce-144 1.041 26 April 6, 1981 Station No. 37 Isotope Activity in pCi/gm Zr-95 .717 i .155 Ru-103 .234 1 060

. Cs-137 None detected Ce-141 .514 1 061 Ce-146 .980 1 264

4. Commercial Feed; Station No. 35 Cs-137 activity in pCi/kg-36.2

5. Soil Samples Cs-137 Activity Station No. 35 (Stevens Farm)

April 14,1981 - 1.34 i .04 pCi/gm Station No. 37 (Central Station)

April 6,1981 .373 i .023 pC1/g

6. Dose Projections Assuming a 248 pCi/1 concentration of Cs-137 and the NRC Regulatory Guide 1.109, milk consumption ingestion dose f actor for adults, the projected dose rate is 8.3 mrem per year to the liver. This is less than the design objective of 10CFR50, Appendix I.

7. Summary of Preoperational Cs-137 Activity in Milk at Station No. 35 Date Activity in pCi/1 Cs-137 September 6,1972 210 October 24, 1972 . 63 Cow Dry --

January 16, 1973 88 4

February 12, 1973 98 March 15, 1973 57 April 16, 1973 66 May 10, 1973 62 July 5, 1973 100 August 8,1973 - 190 September 4,1973 260 Cow Dry --

May 9,1974 100 June 6, 1974 100 July 11', 1974 120 August 8, 1974 160 September 5,1974 170 October 10, 1974 120 November 7,1974 88 December 5,1974 76 January 15, 1975 75 February 15, 1975 40 March 15, 1975 51 March 21, 1975 Initial Criticality, Unit No. 2 a

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