ML19344D168
| ML19344D168 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 03/03/1980 |
| From: | CONNECTICUT YANKEE ATOMIC POWER CO. |
| To: | |
| Shared Package | |
| ML19344D167 | List: |
| References | |
| NUDOCS 8003110461 | |
| Download: ML19344D168 (1) | |
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g( u ATTACHMENT I EVENT DESCRIPTION On February 21, 1980 with the hypochlorite system operating in a normal mode (one pump in service), the strokc settings on the two hypochlorite injection pumps were cut back from 60% to 40% due to decreased chlorine demand in the plant condensers. It appears that the second hypochlorite injection pump was placed into auto service at this time.
Both hypochlorite pumps were found to be in service on 2/22/80, delivering an average of 35 gallons of 12% hypochlorite per 14 minute injection cycle, above the average of 21 gallons that should have been injected per cycle.
It is likely that total chlorine limits were exceeded on this day, but no actual measurements were availabic.
One hypochlorito pump was taken out of servico. A corroborating test was set up for the following day (2/23/B0) based upon inclement weather conditions on 2/22/B0 and on the opinion that chlorine concentration limits were not thought to havs been exceeded.
The test was conducted on 2/23/80 with both hypochlorite pumps in service for one cycle.
The total chlorine concentration in the plant discharge was determined to be 0.4 ppm.
From these results it was felt that the 0.1 ppm total chlorine limit had been exceeded during the time period that two hypochlorite pumps were in service.
CAUSS The cause of the exceeded total chlorine limit was attributed to the second hypochlorite injection pump being placed into service, delivering a greater hypochlorite volume.
ASSES 5 MENT The Environmental Services Group at Northeast Utilities 'as consulted on this matter and it was their concerted opinion that ths wtal chlorine levels attained would have no adverse effect on river bicea.
CORRECTIVE ACTION Taas were placed oa each of the hypochlorite injection pur.aps to provent operation of two pumps simultaneously, and a change is being made to procedure NOP 2.20-4, entitled, " Start-Up and Operation of Hypochlorite Systoa", to have an additional. caution stating that only one hypochlorito injection pump shall ha in service at one time. An investigation on the use of electrical interlocks which preclude opcration of both pumps will also be performed.
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