ML19275A937

From kanterella
Jump to navigation Jump to search
Nonroutine 10-Day Rept 75-05 Re 750904 Unplanned Radioactive Release to Auxiliary Bldg Sump.Caused by Improperly Positioned Waste Gas Sys Delay Tank valve.Xe-133 Released to Atmosphere within Tech Specs Limits
ML19275A937
Person / Time
Site: Three Mile Island Constellation icon.png
Issue date: 09/05/1975
From: Colitz J
METROPOLITAN EDISON CO.
To:
References
NUDOCS 7910240946
Download: ML19275A937 (2)


Text

'

/ . /

4r b'i;;ru A

  • TRO PO LI TAN EDI SON CC M PANY suosioisar or centeauusuc vriu ries canona riou FICE DOX 480 MID DLETOW N. PeNNSYLV ANIA 17057 TELEPHONE 717-944 4041 Septestber 5,1975 10 Day Nonroutine Report No. 75-05 Mr. J.P. O'Reilly Directorate of Regulatory Operations Region I 631 Park Avenue King of Prussia. Pa. 19406 Operating License DPR-50 Docket 50-289

Subject:

Unolanned Release of Radioactive Material at Three Mile Island through the Plant Vent from the Auxiliary Building.

Dear Mr. O'Reilly:

Tiits telegram is to confirm the conversation between Mr. i.ee Spessued (Region I-NRC), and J.J. Colitz (TMI Unit 1 Superintendent) at 1400 hours0.0162 days <br />0.389 hours <br />0.00231 weeks <br />5.327e-4 months <br /> 5 September 1975.

On 4 Septe.ber 1975 between 1530 and 1800, an inadvertent release of radioactive material occurred over a period of approximately 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and 30 minutes.

The inadvertent radioactive material release occurred due to a drain pot drain valve ('4G-V14) associated with the Waste Gas System Delay Tank being left in the open position following the routine draining of the drain pot. All gas leakage, as a result of the open drain valve, was routed directly to the Auxiliary Building sump and then released to the atmosphere via the Auxiliary Building Ventilation System. Analysis of the radiation effluent monitor (R:1-A8) re-corder charts and local Auxiliary Building samoles indicated the radioactive

~. cerial released was prModnately 133Xe (99%), and that the instantaneous noble gas release rate was 4.3 x 10+3 N3 /Sec. which is below the technical

pecification limit of 1.2 x 10+5 M 3/Sec. The average releast. rate over tne 2 hcur and 30 minute pericd of this release was 2.14 x 10+3 MJ/Sec. with a total release of noble gas of 5.75 curies.

This incident may have caused the release of radioactive materials in concentration reportable under caragranh 20.403 (b) (2) of 10 CFR 2n.

7910240 jh^

f ,

Y

Mr. J.P. O' Reilly Septemdery 5, 1975 Page c Following RMS indication that an unolanned re'. case was in progress, an .

imediate investigation to detennine the source was initiated. The in-vestigation revealed that WCG-V14 was open. WDG-V14 was imediately closed and the unplanned radioactive release was tenninated.

Appropriate corrective action will t:e instituted following review of the existing procedural steps relating to 'daste Gas Delay Tank - Drain Tank -

operation.

Very truly yours.

$A uJ.J. Colitr Unit l' Superintendent JJC/dmn 9

, .  ?