ML19332B257
| ML19332B257 | |
| Person / Time | |
|---|---|
| Site: | Fort Saint Vrain  |
| Issue date: | 09/18/1980 |
| From: | PUBLIC SERVICE CO. OF COLORADO |
| To: | |
| Shared Package | |
| ML19332B255 | List: |
| References | |
| NUDOCS 8009260374 | |
| Download: ML19332B257 (1) | |
Text
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-1 This report contains the highlights of the Fort St. Vrain, Unit No. 1 activi-ties, operated under the provisions of the Nuclear Regulatory Commission Operating License, DPR-34.
This report is for the month of April,1980.
1.0 NARRATIVE SU'ttARY OF OPERATING EXPERIENCE A'iD MAJOR SAFETY RELATED MAINTENANCE 1.1 Summarv On April 1, 3980, the reactor power was increased f rom 45% to 60%,
190 megawatts electrical, and held approximately at this level pending cleanup of the primary coolant oxidants.
"D" circulating water pu=p expansion bellows ruptured and required isolation pending repair.
Experienced problems with the reverse osmosis unit in that the re-jection rate was unacceptable. The unit was chemically cleaned, and the membrane seals were replaced on April 2, which corrected the problem.
On April 2,1980, problems developed with the backup bearing water system, which was traced to improperly working control valves.
The problem was corrected and backup bearing water system was placed in service.
On April 4,1980, reactor power was being =aintained at 68%
when total oxidants increased sharply to approximately 50 ppm.
Electrical load was reduced to 185 megawatts. The sudden increase in oxidants is believed to be caused by a calfunctioning helium recovery compressor. The buffer flows to all circulators were re-duced and the recovery compressors vented. By April 5, primary coolant oxidants were reduced to 40 ppm, with reactor power being
=aintained at 56%.
During this period, "B" circulator buf fer knock-out pot required draining frequently. One attempt to drain the knock-out pot resulted in tripping "B" circulator off line.
"B" circulator was recovered for normal operation.
At this time, (April 7), it was decided to take "B" circulator dcun to ir.vestigate what ef fects it might have on the ability to reduce total oxidants.
On April S,1980, while operating at 150 megawatts electrical, a loop shutdown was received during an attempt to restar: "3" circu-lator.
The recovery of the loop was severely hampered Ly fre'quent loss of power to secondary coolant drain pac.'. valves.
This loss of power was caused by blown fuses. A testing system. which is still in progress, was initiated to determine the cause.
The loop was recovered and reactor power was increased to support 65 megawatts electrical load on April 9,19S0.
Region outlet temperatures were being controlled below.200*F until total oxi-dants decreased belcw 10 ppm.
Reactor pover was changed over the few days between 30% and 65* as dictated by pri:2ry coolant next i
cxidant levels.
The "3" and "C" circulaters were removed frem i
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