ML20084E616

RO:720831 & 0901 Unplanned Release of Radioactive Passes Occurred During Removal of Spent Resins from Spent Resin Tanks.Cause Not Stated.Written Procedure for Handling Resin Revised & Precaution Included Re Vent Header Pressure

ML20084E616
Person / Time
Site:	Ginna
Issue date:	12/28/1972
From:	Amish K ROCHESTER GAS & ELECTRIC CORP.
To:	Oleary J US ATOMIC ENERGY COMMISSION (AEC)
References
NUDOCS 8304150163
Download: ML20084E616 (2)

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December 28, 1972 Mr. John P. O' Leary, Director

. Directorate of Licensing U.S. Atomic Eneroy Commission Washington, D. C. 20545 l,

Subject:

R. E. Ginna Nuclear Power Plant Unit No.1 Docket 50-244 p!

Dear Mr. O' Leary:

C- 2 Between 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> on August 31,1972 and 1100 hours0.0127 days <br />0.306 hours <br />0.00182 weeks <br />4.1855e-4 months <br /> on September 1,1972 an unplanned release of radioactive gasses occurred at the Ginna Station.

l This is documented by an increase in the count rate on the plant vent monitor -

! and by the loss of gas volume from the #2 gas decay tank which was in service. During this period no other releases were in progress. One auxiliary -

i building exhaust fan, the gross activity monitor, the iodine activity monitor .

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j and the particulate monitor were in operation.

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The release rate was below Technical Specifications and involved no exposure of individuals. Calculation of the twenty-four hour average release rate as 7 provided in the Technical Specifications Section 3.9.2.3 for this mixture 1 y indicates 0.00264 Ci/second. The limit value is calculated to be 0.0402 Ci/ ~

second as determined by Technical Specifications Section 3.9.2.1. The ...

release was approximately six (6) percent of the limit value. During this period 228 curies were released as compared to the present normal of 5 C1/24

-hour period. The curies released were determined from the computer log print-1 out of the plant vent gas monitor. The concentration of the gasses determined

at the vent monitor is compared to a weekly vent sample analyzed by the plant a j health physicc and chemistry section. This sample had been taken in the

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morning pricr to the release and showed the plant vent gas monitor to be in . .

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calibration. The gasses released, as well as the normally vented gas, all -

pass through charcoal and HEPA filters and no measureable iodine or partic-ulate was released. -

The incident occurred during removal of spent resins from the Spent Resin Tanks.

Nl While venting the tank to the cover gas system a three (3) psig pressure was geo developed in the vent header for a short period of time. This increased pressure g applied to the gas cover of the charging pump leakoff collection tank was .. ..

@ sufficient to start a siphoning effect on this tank. The collected water in this 4 Nn tank was emptied through its overflow drain to the sump tank and thence directly 0 by pipe to the auxiliary building exhaust and did not present a hazard to oper-n oc ating personnel. When the siphoning was discovered and stopped, the charging pump leak-off tank returned to normal operation, the gas loss stopped, and the

$$ plant vent gas monitor returned to its former normal reading.

om g Thi.s was the first time in the plant history that the spent resin removal from the yu a,e L

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., December 28, 1972

,a Mr. John I'. O' Leary l - .

Spent Rosin Tanks was performed. As a result of this incident, the written plant procedure (S4.4) for handling resin has been revised and precaution against exceeding a vent header pressure of two (2) psig has been included.

4 This precaution is identified in two different steps of the operating instruc-tion checkoff, if the pressure is exceeded the instruction requ;res that the

leak-off collection tank be checked to ensure that the seal is not overflowing.

J A vent header pressure gauge has been installed at the spent resia control e station to assist the operator in monitoring the vent header pressure while

) performing the release of gas from the spent resin tank. In addition, the auxiliary operator will monitor the waste gas system during the operation.

! This incident has been under discuscion with the compliance inspector in 1 the ensuing period and is presented as a matter of information.

Very truly yours,

[L Keith W. Amish I

i xc: Mr. J. P. O'Rollly E

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