Headquarters Daily Report APRIL 30, 1998 *************************************************************************** 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 - HEADQUARTERS APRIL 30, 1998 MR Number: H-98-0065 NRR DAILY REPORT ITEM GENERIC COMMUNICATIONS Information Notice 98-16, "INADEQUATE OPERATIONAL CHECKS OF ALARM RATEMETERS," will be issued on April 30, 1998. This notice is being issued to all industrial radiography licensees to alert them to an incident where two alarm ratemeters failed to alarm when workers approached an exposed source because inadequate daily checks failed to detect weak batteries. The licensee's operating procedures failed to include all of the instructions in the vendor's manual for performing operational checks. Contacts: Robert G. Gattone, RIII J. Bruce Carrico, NMSS 630-829-9823 301-415-7826 E-mail: rgg@nrc.gov E-mail: jbc@nrc.gov _ HEADQUARTERS MORNING REPORT PAGE 2 APRIL 30, 1998 MR Number: H-98-0066 NRR DAILY REPORT ITEM SIGNIFICANT EVENTS Subject: Inoperable Ice Condensers at DC Cook Units 1 & 2, Classified As A Significant Event The NRR/AEOD/RES Events Assessment Panel on April, 7, 1998, classified the inoperability of the ice condensers at the DC Cook nuclear power plant as a Significant Event for the Performance Indicator Program. The significant event classification was based on the breakdown of the licensee's program for assuring continued operability of the ice condensers to perform their design function of maintaining post-LOCA containment pressure within the design basis. The ice condenser inside the containment of each DC Cook unit is composed of 1944 baskets, each 12 inches in diameter and 48 feet tall, filled with ice. Post-accident steam released from the reactor coolant system flows into the ice condenser where much of its heat energy is removed by direct contact with the ice, such that the steam is condensed back into water. This effect reduces the pressure inside containment to within design limits. NRC and licensee inspection activities in January, February and March 1998 showed several conditions that raised questions concerning the operability of the ice condenser: - In both units, 10 - 20 % of the steam flow passages between baskets were blocked by frost and ice - lower portions of some ice baskets were devoid of ice - the bottoms of some ice baskets had been structurally damaged, and testing indicated that these baskets might be unable to maintain their structural configuration under accident conditions - screws were missing from section couplings and lower rims of the baskets - the licensee reported that trash, such as plastic, wire and wood, had been frozen into the ice; it was collected when ice was melted from some of the baskets, and might have caused pluggage of the containment sump screens when the ice melted following a loss-of-coolant accident - the licensee had been selecting a non-representative sample of ice baskets when performing ice weight surveillances The licensee plans to melt out the ice from both ice condensers and make the necessary repairs. NRC Region III has issued Inspection Report 50-315/98005(DRS); 50-316/98005(DRS) dated April 10, 1998, which addresses the NRC inspection activities related to these ice condenser matters. HEADQUARTERS MORNING REPORT PAGE 3 APRIL 30, 1998 MR Number: H-98-0066 (cont.) There are seven other nuclear power reactors with ice condenser containments operating in the United States. All are located in NRC Region II and have been alerted to the problems at DC Cook. Region II is developing an ice condenser inspection plan for application to those plants. Contact: James Gavula, Region III (630) 829-9755 E-mail: JAG1@nrc.gov John Stang, NRR/DRPW/PDIII-2 (301) 415-1345 E-mail: JFS2@nrc.gov Robert A. Benedict, NRR/DRPM/PECB (301) 415-1157 E-mail: RAB1@nrc.gov _ REGION II MORNING REPORT PAGE 3 APRIL 30, 1998 Licensee/Facility: Notification: Southern Nuclear Operating Co. MR Number: 2-98-0021 Farley 1 2 Date: 04/30/98 Ashford,Alabama Dockets: 50-348,50-364 PWR/W-3-LP,PWR/W-3-LP Subject: MANAGEMENT CHANGES AT FARLEY Discussion: Southern Nuclear Operating Co., Inc. (SNC) announced on April 28, 1998, that effective May 30, 1998, Richard Hill, General Manager, Plant Farley, will become General Manager, Nuclear Support, Farley Project, and relocate to Birmingham. Mike Stinson, currently Assistant General Manager, Operations, will assume Hill's position as General Manager, Plant Farley. Don Grissette, Operations Manager, will become Assistant General Manager, Operations, and Randy Johnson, Maintenance Manager, will become Operations Manager. Regional Action: For information only. Contact: ROBERT CARRION (404)562-4522 _ REGION IV MORNING REPORT PAGE 4 APRIL 30, 1998 Licensee/Facility: Notification: Texas Utilities Electric Co. MR Number: 4-98-0022 Comanche Peak 1 Date: 04/29/98 Glen Rose,Texas Resident Inspector Dockets: 50-445 PWR/W-4-LP Subject: Reactor Trip Breaker Failure Discussion: On April 26, 1998, while in Mode 3 preparing for startup, a Westinghouse DS-416 reactor trip breaker failed to close during rod drop testing. Licensee investigation revealed that a washer, which was part of the shunt trip attachment, had been placed on the wrong side of the shunt trip latch pivot pin retaining clip. The washer migrated across the pivot pin to a point where it jammed against the close cam when the breaker motor attempted to charge the closing spring. The motor failed to charge the closing spring and the breaker would not close. The reactor trip breakers at Comanche Peak are designed to charge the closing spring after the breaker trips open (known as a 6a wiring scheme). Because of this scheme, the improper washer placement would not prevent a shunt trip of the breaker. If the motor completes charging of the closing spring, then the physical arrangement of the pivot pin, the close cam, and the washer would ensure that the shunt trip pivot pin is free to trip open the breaker. However, the DS-416 breaker is also used in numerous other 480 volt applications both safety and nonsafety. In the majority of these other applications, the breaker motor charges the closing spring after the breaker is shut (7a wiring scheme). In these cases, an improperly positioned washer could bind against the close cam and bind the shunt trip pivot pin. In these cases, a shunt trip of the breaker may not occur. The shunt trip assembly is part of the power operating mechanisms(POMs). The POMs, Model No. 567F759G02, on the reactor trip breakers and the reactor trip bypass breakers had been replaced during the recent outage with new ones purchased from the vendor. The defective POM was received from the vendor assembled incorrectly. The licensee replaced the defective POM with one from the warehouse, and verified that the POMs in the other three reactor trip/bypass breakers and in the warehouse were correctly assembled. The licensee is also inspecting other breakers throughout the plant for proper assembly of the POMs. To date no other incorrectly assembled POMs have ever been identified by the licensee. Regional Action: The resident inspectors observed the licensee's inspection of the breakers and are following the licensee's actions on the resolution of the problem. Contact: Harry A. Freeman (254)897-1500 Ronald A. Kopriva (817)860-8104 Joseph I. Tapia (817)860-8243 _ REGION IV MORNING REPORT PAGE 5 APRIL 30, 1998 Licensee/Facility: Notification: Nebraska Public Power District MR Number: 4-98-0023 Cooper 1 Date: 04/30/98 Brownville,Nebraska Senior Resident Inspector Dockets: 50-298 BWR/GE-4 Subject: MANAGEMENT CHANGES AT NEBRASKA PUBLIC POWER DISTRICT (COOPER NUCLEAR STATION) Discussion: Effective April 30, 1998, Paul J. Caudill, the Senior Manager of Safety/Site Support, was named as the interim Senior Engineering Manager. Mr. Caudill will hold this position until a permanent replacement is identified. The new Senior Manager of Safety/Site Support has not been named. James P. Pelletier, former Senior Engineering Manager will remain with Nebraska Public Power District as an assistant to John H. Swailes, Vice President of Nuclear Energy. All positions are located on site. Regional Action: For information only. Contact: Elmo Collins (817)860-8291 _