ML19326D856
| ML19326D856 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 07/15/1980 |
| From: | TENNESSEE VALLEY AUTHORITY |
| To: | |
| Shared Package | |
| ML19326D854 | List: |
| References | |
| NUDOCS 8007230452 | |
| Download: ML19326D856 (2) | |
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LCO VIOLATION' REPORT,
BROWNS FERRY NUCLEAR PLANT Description of Violation On July 6, 1980, the river temperature exceeded the maximum limitation of 90.0 F from 5:00 p.m. CDT until 6:15 p.m. CDT at the downstream monitor.
The maximum downstream temperature of the reservoir which occurred during this period was 90.2 F at 5:29 p.m. CDT.
Cause of Violation The pr
'c
.* coi' uter program underastimated the maximum downstream
.ne period of violation by 0.2 F.
Because of the temperas.
c underest-J a rapid increase in the downstream temperature, the planc..'_. not react quickly enough to avoid the violation.
Analysis of Violation An analysis of the reservoir temperature before and after the violation indicates that the Environmental Technical Specification limit regarding temperature increase was exceeded. This information is shown on the attached graph. Since the violation only lasted for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 15 minutes and the m ximum limit was only exceeded by 0.2 F, no significant adverse environmental impact was experienced in Wheeler Reservoir due to plant-induced heating.
Corrective Action When it was noted at 1:38 p.m. CDT that.he temperature continued to g
approach the maximum limit of 90.0 F, platt personnel began using the cooling tower for one unit. The second unit was put on the cooling towers at 3:55 p.m. CDT after noticing that the downstream temperature was 89.7 F and till rising. At 3:55 p.m. CDT, the station load was reduced by 50 megawatts. Since the downstream temperature continued to rise, plant personnel reduced the station load by an additional 50 megawatts at 4:38 p.m. CDT.
As a result of these actions,_the duration and magnitude of the downstream temperature violations were minimized.
Recommendation to Avoid Future Violations If the predictive computer program estituttes that the downstream e
reservoir temperature will reach 90.0 F, mitigative action will be taken sooner.
Attachme'at 800723o4 %
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a DOhNSTREtV1 RIVER TEMPERATURE AND DELTA TDIPERATURE JULY 6, 1980
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90.2 F @ 1729 hours0.02 days <br />0.48 hours <br />0.00286 weeks <br />6.578845e-4 months <br /> Temperature b
90.0 F Limit 0
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