Headquarters Daily report MARCH 16, 1995 *************************************************************************** REPORT NEGATIVE NO INPUT ATTACHED INPUT RECEIVED RECEIVED HEADQUARTERS X REGION I X REGION II X REGION III X REGION IV X *************************************************************************** PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION II MARCH 16, 1995 Licensee/Facility: Notification: Florida Power & Light Co. MR Number: 2-95-0030 Saint Lucie 1 Date: 03/16/95 Florida Dockets: 50-335 PWR/CE Subject: FAILED ROSEMOUNT PRESSURE TRANSMITTERS DUE TO GAS PERMEATION Reportable Event Number: N/A Discussion: On March 15, 1995, the vendor informed the licensee and the NRC that the cause for two Rosemount pressure transmitter failures was hydrogen permeation of the isolating diaphragms. The permeation was the result of improperly fabricated sensing modules, which contained monel diaphragms, as opposed to 316 stainless steel (which the design called for). Monel is highly susceptible to permeation from hydrogen, and the hydrogen present in the reactor coolant system appeared to lead to the failure mode. The failed pressure transmitters were manufactured by Rosemount, model number 1153. Serial numbers indicated that the transmitters had been refurbished by the vendor due to a susceptibility to oil leakage. A review of the transmitter output indicated that the failures involved a gradual increase in output over an approximate 5 minute period, culminating in an output plateau near the upper end of the transmitters' ranges. The two failures occurred approximately 10 minutes apart. Transmitter outputs remained constant following the event, and only abated when output leads were lifted and relanded. Loop calibrations were subsequently performed, and both transmitters showed extremely slow response. The transmitters were subsequently replaced. The vendor is currently attempting to bound the possible population of nonconforming transmitters. Regional Action: The resident inspectors are following the licensee's and vendor's actions. Region II has provided this information to NRR. Contact: K. LANDIS (404)331-5509 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION II MARCH 16, 1995 Licensee/Facility: Notification: Entergy Operations, Inc. MR Number: 2-95-0031 Grand Gulf 1 Date: 03/16/95 Port Gibson,Mississippi Dockets: 50-416 BWR/GE-6 Subject: PRELIMINARY INFORMATION FOR THE GRAND GULF REACTOR SCRAM Reportable Event Number: 28540 Discussion: A Division II half scram was inserted to allow an I/C surveillance on APRM Channels B (06-IC-1C51-SA-0001-2, APRM Monitor Calibration). No half-scram existed on Division I prior to commencement of surveillance testing. Within a minute, Low CRD Air Header Pressure alarm annunciated. Control rods started to drift in as indicated by Rod Drift alarms on the main control panel. Almost immediately the reactor automatically scrammed. The operator did not have time to insert manual scram in response to the drifting rods. Reactor scrammed at 4:26 a.m. on 3/16/95 due to low reactor vessel water level (Level 3). Low water level was probably caused from the 'shrink' that would be expected as the power decrease when the drifting rods collapses the voids in the core. Plant response following the scram was normal. Reactor vessel level was maintained at 30" by feedwater control system on startup level control valve. The plant will remain in shutdown (Mode 3) pending completion of the investigation into the cause for the scram. Regional Action: Resident inspectors responded to the site shortly after the scram occurred and will continue to monitor the licensee's activities. Contact: FLOYD CANTRELL (404)331-5534