Headquarters Daily report JUNE 28, 1994 *************************************************************************** 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 I JUNE 28, 1994 Licensee/Facility: Notification: Maine Yankee Atomic Power Co. MR Number: 1-94-0072 Maine Yankee 1 Date: 06/28/94 Wiscasset,Maine 6/23 SRI TELECON Dockets: 50-309 PWR/CE Subject: POWER REDUCTION TO LESS THAN 2% DUE TO CHLORIDE INTRUSION IN THE STEAM GENERATORS Reportable Event Number: N/A Discussion: On June 19, 1994, a service water leak developed in the non-nuclear safety portion of the related discharge piping. This leak caused the service water sump in the turbine building to overflow, and salt water to enter the adjacent condensate sump. The service water piping leak was stopped with a temporary repair, and both sumps were pumped dry. During this period, condensate pump P-27B was being overhauled, and its drain and vent valves were opened. The overflow of salt water into the condensate sump resulted in salt water entering the condensate pump via the open drain line. However, the licensee had not recognized the intrusion of salt water into the pump prior to returning it to service on June 22. Early on June 23, a chemistry sample of the steam generators indicated a chloride concentration of 2764 ppb in steam generator 2. Operators initiated maximum blowdown in an attempt to reduce the chloride concentration. Condensate pump 27B was isolated after a condensate sample indicated high chlorides (about 31,000 ppb) in the hotwells. A power reduction at a rate of 20% per hour was commenced at 3:50 AM on June 23. At 9:22 AM, the unit was placed in hot standby (below 2% power). The plant continued cleanup activities in all steam generators to reduce the chloride levels below the EPRI guidelines. Station administrative controls require that chloride levels be at less than 100 ppb at or below 30% power and below 20 ppb at power levels above 30%. On June 28, after the chloride levels were reduced to below 100 ppb, the plant increased power to 10% and the main generator was synchronized to the grid at 7:25 AM. Cleanup activities continue and the plant will remain below 30% power until the chloride levels in the steam generator are reduced to below 20 ppb. Maine Yankee is continuing their investigation of the chloride intrusion into the steam generators. Regional Action: The resident inspectors are monitoring the power escalation and cleanup activities and the licensee's followup actions. Contact: Jimi Yerokun (207)882-7519 William Lazarus (610)337-5231 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION IV JUNE 28, 1994 Licensee/Facility: Notification: Wolf Creek Nuclear Oper. Corp. MR Number: 4-94-0060 Wolf Creek 1 Date: 06/28/94 Burlington,Kansas Resident Inspector Dockets: 50-482 PWR/W-4-LP Subject: LICENSEE MEETING WITH THE RESIDENT INSPECTOR Reportable Event Number: N/A Discussion: On June 27, 1994, Westinghouse advised the licensee of a design problem with new fuel that Wolf Creek has received. In response to core periphery flow vibration causing fuel failures at Beaver Valley and Salem, Westinghouse redesigned the fuel assembly by rotating some of the grid straps 90 degrees thus reorienting the mixing vanes. Individuals on the AP-600 advanced reactor program recently requested Westinghouse to perform some additional DNB studies. These studies revealed that this rotation of the grid straps affected flow enough to impart as much as a 16.5 percent DNB penalty. This fuel is currently in use at Millstone Unit 3 and at two Korean nuclear units. The following four sites are currently receiving this newly designed fuel in preparation for future refuelings: Wolf Creek, D.C. Cook, Braidwood, and Byron. Options for the receipt of the new fuel include shipping it back to Westinghouse for rework and use of the fuel in conjunction with a reanalysis and possible derate of the unit. Regional Action: The resident inspector and Regional staff will monitor licensee actions. Contact: Melanie Miller (817)860-8127