Headquarters Daily Report SEPTEMBER 16, 1997 *************************************************************************** REPORT NEGATIVE NO INPUT ATTACHED INPUT RECEIVED RECEIVED HEADQUARTERS û REGION I û REGION II û REGION III û REGION IV û PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION I SEP. 16, 1997 Licensee/Facility: Notification: New York Power Authority MR Number: 1-97-0049 Indian Point 3 Date: 09/16/97 Buchanan,New York SRI PC Dockets: 50-286 PWR/W-4-LP Subject: REACTOR TRIP DUE TO A FAILED RELAY CONTACT DURING SURVEILLANCE TESTING Reportable Event Number: 32930 Discussion: On September 15, at about 4:29 p.m., the reactor tripped from 30 percent power while performing testing of the pressurizer pressure instrumentation. The licensee's investigation into the cause of the trip revealed a high resistance contact in a BFD-66 relay in the reactor protection system (RPS). The high resistance in this normally closed contact provided a low pressurizer pressure input to the Reactor Protection System. However, no other indications were available to indicate that this condition existed because the other contacts associated with the relay operated properly. When the low pressurizer pressure bistable of another RPS channel was placed in the trip condition for the surveillance test the RPS two of four logic was satisfied and caused the Reactor Protection System to activate. The plant was placed in the hot shutdown condition without complication. Equipment performed as required in response to the trip. The licensee is conducting a post transient review of the trip. The plans to return the unit to service included checking resistances across relay contacts associated with all reactor protection system logic matrices. A subsequent evaluation to determine whether additional checks are required is pending the outcome of these checks. Regional Action: The resident inspector responded to the site following observed the licensee's troubleshooting activities and continue to follow licensee's actions. Contact: John Rogge (610)337-5146 _ REGION IV MORNING REPORT PAGE 2 SEPTEMBER 16, 1997 Licensee/Facility: Notification: Houston Lighting & Power Co. MR Number: 4-97-0070 South Texas 1 Date: 09/15/97 Wadsworth,Texas By phone call from resident insp. Dockets: 50-498 PWR/W-4-LP Subject: UNIT 1 CONTROL ROD TESTING Discussion: On September 13, 1997, South Texas Project Unit 1 was removed from service for a refueling/maintenance outage. As part of this evolution, rod drop testing was performed to gather additional information on the previously identified conditions described in NRC Bulletin 96-01, "Control Rod Insertion Problems." During the test, seven rod cluster control assemblies (RCCAs) failed to fully insert. Three of the assemblies inserted to a position 6 steps (3 3/4 inches) withdrawn, three assemblies inserted to a position 12 steps (7 1/2 inches) withdrawn, and the remaining assembly stopped between 22-38 steps (13 3/4 - 23 3/4 inches) withdrawn. These results were predicted by previous mid-cycle rod drop data and were not unexpected with one exception. The magnitude of previous results did not exceed 12 steps withdrawn and the one rod that remained between 22 and 30 steps withdrawn indicates a worsening of the condition with time. All 7 assemblies were subsequently driven to rod bottom utilizing the control rod drive system. During this process, one nonaffected rod failed to insert when the moveable gripper mechanism became misadjusted. The licensee will be removing and replacing RCCA's as appropriate. All of the data obtained from the rod testing is currently being review by the licensee. Regional Action: The resident inspectors were on site during the rod drop testing and are continuing to review the licensee's evaluation of the rod drop data. NRR has been informed of the preliminary results, and plans to discuss future start up and rod drop testing plans with the licensee. Contact: Joseph I. Tapia (817)860-8243 Ronald A. Kopriva (817)860-8104 _ REGION IV MORNING REPORT PAGE 3 SEPTEMBER 16, 1997 Licensee/Facility: Notification: Entergy Operations, Inc. MR Number: 4-97-0071 River Bend 1 Date: 09/16/97 St Francisville,Louisiana Senior Resident Inspector Dockets: 50-458 BWR/GE-6 Subject: UNEXPECTED INCREASE IN REACTOR COOLANT TEMPERATURE Discussion: On September 13, 1997, with the plant in Cold Shutdown (Mode 4), the licensee began testing the alternate decay heat removal (ADHR) function of the newly installed suppression pool cleanup system. Initially, reactor coolant temperatures indicated 129 degrees F at the shut down cooling heat exchanger inlet. At 11:47 a.m. (CDT), shutdown cooling was secured. At 1:24 p.m. (CDT), when operators placed ADHR in service, they noted that the ADHR heat exchanger inlet temperature had increased to 210 degrees F, while the temperature at the RWCU indicated 160 degrees F. They concluded that the plant may have re-entered Mode 3 (RCS temperature greater than 200 degrees F). At approximately 4 p.m., ADHR indicated 140 degrees F while RWCU indicated 109 degrees F. An important difference between ADHR and normal shutdown cooling is that ADHR discharges directly into the core via low pressure coolant injection Path C, whereas, normal shutdown cooling discharges into the feedwater sparger in the downcomer annulus. There are no temperature instruments monitoring the temperature inside the core. The ADHR temperatures may have indicated coolant mixed from the core when ADHR circulation was placed in service. The licensee implemented a Significant Event Response Team (SERT) to determine the cause of the event, evaluate the impact on plant conditions, and determine the safety significance. Regional Action: The resident inspectors are reviewing the licensee's investigation results. Contact: E. E. Collins (817)860-8291 W. F. Smith (504)635-3193 _