ML19338F908
| ML19338F908 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 09/05/1974 |
| From: | Heider L YANKEE ATOMIC ELECTRIC CO. |
| To: | US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML19338F906 | List: |
| References | |
| WYR-74-20, NUDOCS 8010270610 | |
| Download: ML19338F908 (3) | |
Text
(
L-..
)~
Telephone 617 366-9011 rwz 7 0 390 0739 YAlllWE ATOTAIC ELECTRIC COPAPAllY ura 74-20 3
- -t 20 Turnpike Rood Westborough, Mossochusetts 01581 Yimm,.a1es
~~
September 5, 1974 United States Atomic Energy Commission Washington, D. C.
20545 Attention: Directorate of Regulatory Operations
Reference:
License No. DPR-3 (Docket No. 50-29)
Dear Sir:
Pursuant to the requirements of Section 20.405 of 10CFR20, the Yankee Atomic Electric Company submits the following 30 day report.
On August 6, 1974 a Yankee Atomic Electric Cc=pany e=ployee was exposed to radioactive airborne concentrations in excess of the limits as specified in 10CFR20, Appendix B, Table 1.
The exposure occurred during a control rod housing venting procedure.
This is a routine operation that is performed following reinstallation of the reactor vessel head. This operation had been done three weeks earlier with no increase in airborne activity.
The venting of the control rod housings co==enced at 1330 on August 6, 1974. Although health physics coverage was provided, Health Physics supervision judged'that respiratory protection was not necessary.
This was a violation of a Health Physics procedure which states that Respiratory Protection is required when venting systems containing main coolant water.
The following is a chronology of the event:
1330 hours0.0154 days <br />0.369 hours <br />0.0022 weeks <br />5.06065e-4 months <br /> - Venting started 1400 hours0.0162 days <br />0.389 hours <br />0.00231 weeks <br />5.327e-4 months <br /> - A bucket containing drained nain coolant was measured by the H.P. can and found to be reading % 300 cr/hr. At this point, a continuous air sample which had been running in the general vicinity since 1130 hours0.0131 days <br />0.314 hours <br />0.00187 weeks <br />4.29965e-4 months <br /> was moved into the venting area.
1425 hours0.0165 days <br />0.396 hours <br />0.00236 weeks <br />5.422125e-4 months <br /> - Air sample was changed. At the same time, the operator donned respiratory protection. The work was completed at 1500 hours0.0174 days <br />0.417 hours <br />0.00248 weeks <br />5.7075e-4 months <br />.
8010270 [/O
A
[~
i 4
% United States Atomic Energy Co==ission September 5, 1974 Attn: Directorate of Regulatory Operations Page Two 1515 hours0.0175 days <br />0.421 hours <br />0.0025 weeks <br />5.764575e-4 months <br /> - While checking out at the control point, the operator discovered he was contaminated. An analysis of the air sample and a ecm-putation of the time / activity value indicated the possibility of an overexposure.
Nose and throat swabs were taken. The nose swabs were N 400 dpm. The man was then decontaminated to background icvels.
The man was given a body burden count and a program of urine samples was initiated.
The calculated air activity sample was:
J C
2.04 x 10- pei/ml 3.54 x 10_7 pei/ml 58 C
7 54 Mn 1.69 x 10- uc /ml 2 20 x 10_7 pei/ml 59 Fe 7
51 Cr 5.04 x 10 pei/ml The G.I. Tract dose esticate for a single uptake by comparison with !TC was 24 tRem. The dose to the lung was determined to be 405 mrem. The results of the urine assay program were negative. The body burden analysis verified the calculated exposure results. Calculations for both the lung and G.I. tract were done for non-transportable radionuclides.
The exposure was caused 'uy a violation of an established procedure.
The individuals involved were debriefed after the incident; in addition, a general plant meeting was held for the purpose of discussing the incident with all plant e=ployees.
The venting procedure was subsequently modified to preclude the possi-bility of air release to the at=osphere.
Very truly yours, YANKEE ATOMIC ELECTRIC COMPANY L. H. Heider Manager of Operations HFB/kg i
h 4
, -... - ~. _ _ -. - - - -... - -.. -..
V"
^
[
o 6
'_ j c
i Addendum to the Yankee 30-day letter of the particulate release' incident of August 6i 1974.
t The calculated exposure to the man involved on August 6, 1974 is tabulated and reported below as required in Section 20.405(b)' of 10CFR20.
I r
}
1 l
1 4
4 i
l l
i 1
i I
F