ML17252A991

Letter Reporting 03/21/1973 and 03/23/1973 Conditions Relating to the Discovery of Radwaste Above Ground Storage Tanks to Contain 4.05 and 1.00 Curies Respectively, Which Exceeds Technical Specifications - Dresden Units 2 and 3

ML17252A991
Person / Time
Site:	Dresden
Issue date:	03/30/1973
From:	Worden W P Commonwealth Edison Co
To:	Giambusso A US Atomic Energy Commission (AEC)
References
WPW Ltr. # 253-73
Download: ML17252A991 (2)

Text

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*--... .' *-* ----*---------* .. ; .. ' -: J 50-237 Commonwealth Edison Company . _Mr. A. Giambusso Deputy Director for Reactor Projects Directorate of Licensing U. s. Atomic Energy Commission Washington, D. c. 20545 CHICAGO, llllNOIS 60690 Dresden Nuclear Power Station R. R. #1

• Morris, Illinois March 30, 1973 60450

SUBJECT:

LICENSE DPR 19-25. DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3, SECTION 6. 6.B. 3 OF THE TECHNICAL SPECIFICATIONS.

Dear Mr. Giambusso:

• 'This is to *report *a condit*ton *rel-a*ting *to the -o.£ the station in which on March 21 and 23, 1973, Radwaste above ground storage tanks were found to contain and 1.00 curies respectively, which exceeds the Technical Specification limit as stated in Section 3.8.D. PROBLEM AND INVESTIGATION . The following circumstances led to the "C" Waste Sample Tank content of 4.05 curies on March 21, and the Waste Surge Tank content of 1.00 curies on March 23, 1973: The Waste Collector Tank was processed to "C" Waste Sample Tank through "B" Waste Collector Filter bypassing the demineralizer due to the high conductivity of the water. The high_conductivity water was apparently the result of water carryover from the Waste Concentrator. On March 21, 1973, at 2055, the sample on "C" Waste Sample Tank indicated an activity of 3.6xl07 uuCuries/liter which corresponds to 4.05 curies. The "C" Waste Sample Tank was then pumped to an underground tank, "B" Waste Neutralizer, on March 22 at 1730. By March* 23 at 0710, the entire "C" Waste Sample.Tank had been pumped to the Waste Neutralizer for processing through the Waste Concentrator.

Mr.n A. Giambusso ,, "..:..,. ..

• March 30, 1973 On.March 23, the Waste Collector Tank was processed to 11C11 Waste Sample Tank and sampled. The sample analysis showed the tank activity to be l.56xl06 uuCi/liter which corresponds to less than the Technical Speci* fication limit of .7 curies. However, the conductivity of this water was unacceptable for storage. 11C" Waste Sample Tank was then pumped to the Waste Surge Tank. It appears that resi<iual on the bottom of the Waste Surge Tank caused the total activity of this tank to be 1.00 curies when the sample was analyzed at 1730 hours0.02 days <br />0.481 hours <br />0.00286 weeks <br />6.58265e-4 months <br /> March 23. A portion of the water in the Waste Surge Tank was processed through a filter and demineralizer which reduced the tank curie content to 0.27 curies as shown by the sample *analysis on *March 24,

• 1:973. a*t 1715. The presence of 4.05 and 1.00 .curies in the 11c11 Waste Sample Tank and Waste Surge Tank at different times did not present a hazard to the public since the contents of the tanks were not released to the river and radioactivity was reduced to less than Technical Specification limits. within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> following collection and analysis of the samples. Had a failure of the above ground tanks occurred, as described in Admendment #9,Section V.C.l of the S.A.R., and the radioactivity contained in the tanks been released to the aquatic environment, the limits as specified in 10 CFR 20.106 would not have been exceeded when averaged over one year. CORRECTIVE ACTION In order to minimize the potential for future incidents of this nature, a procedure will be issued by April 3, 1973, requiring sample analysis and calculations of curie content prior to processing to.above ground radwaste storage tanks without the use of either a waste collector filter or the radwaste demineralizer. WPW:do cc: . WPW Ltr. File Sincerely, W. P. Worden Superintendent