FPL generates incident reports to NRC … by gimleteye

A dead American crocodile was recently sucked onto the intake grill of the Turkey Point nuclear plant, FPL reported to the Nuclear Regulatory Commission. On August 11th, only a few days after the NRC approved running the two nuclear plants with hotter cooling water, there was another problem at the plant warranting a report to the NRC:

MANUAL REACTOR TRIP ON LOSS OF INSTRUMENT AIR FOLLOWED BY SAFETY INJECTION

"This is an non-emergency notification to the NRCOC [Nuclear Regulatory Commission Operations Center] in accordance with 10 CFR 50.72(b)(2)(iv)(B) for a valid actuation of the reactor protection system (RPS) (four hour notification) and 10 CFR 50.72(b)(3)(iv)(A) for a valid Engineered Safeguards (ESF) actuation (eight hour notification) due to auxiliary feedwater (AFW) initiation , safety injection (SI) initiation, and emergency diesel generator (EDG) auto start.

"On 8/11/14 at 1028 EDT, Unit 3 experienced a manual reactor trip due to a loss of instrument air. Auxiliary feed water automatically initiated as expected. Unit 3 is currently in Mode 3 and stable. Instrument air has been restored.

"At 1305 a safety injection signal [SI] occurred due to main steamline high differential pressure during a plant cooldown to 470 degrees Fahrenheit. High head safety injection (HHSI) pump, residual heat removal (RHR) pumps, and emergency diesel generators (EDGs) auto started as expected due to the safety injection signal. Based on plant conditions, the HHSI and RHR pumps did not inject into the reactor coolant system."

The plant was stabilized after the reactor trip, however, the loss of instrument air resulted in a loss of letdown and PZR level continued to slowly increase to approximately 91%. All rods fully inserted and normal offsite power was maintained.

Operators initiated a plant cooldown to stabilize and lower PZR level using the S/G atmospheric steam dumps. Unequal opening of the S/G atmospheric steam dumps caused the SI to occur due to main steamline high differential pressure. No RCS injection occurred and all SI equipment operated as expected and has been subsequently secured. Unit 3 is stable in mode 3 at 490 degrees Fahrenheit and RCS pressure is 1940 psig. There was no effect on Unit 4 which continues to operate at 100% power. The loss of instrument air is being investigated.

The licensee has notified the NRC Resident Inspector.

Confidentiality is assured for any insider comments/information on FPL Turkey Point operations.