Event Notification Report for December 02, 2005

OFFSITE NOTIFICATION - ELEVATED LEVELS OF TRITIUM FOUND IN GROUNDWATER

"This notification is being made pursuant to 10 CFR 50.72(b)(2)(xi) for a press release issued by Exelon Nuclear at 10:00 AM CST on December 2, 2005 regarding elevated levels of tritium found in groundwater on the Braidwood Station site property near the plant's north boundary. An environmental monitoring program at the Braidwood Generating Station has found higher than normal concentrations of tritium close to an underground pipe inside the plant's northern boundary, and the station has begun a remediation program. An Exelon Nuclear environmental team is drilling test wells on and just beyond the Braidwood property line in order to determine how much tritium may have moved beyond the plant boundaries and ultimately to clean up the tritium. Exelon Nuclear has notified NRC regional personnel, appropriate state agencies, local and state elected officials and four property owners who are potentially affected.

"The tritium was found in shallow groundwater 8 to 15 feet deep on company property. It poses no health or safety risk to the public and does not threaten drinking water wells in the area. Tritium is a naturally occurring isotope of hydrogen that emits a very low level of radiation and is a natural part of water. It is found in more concentrated levels in water used in nuclear reactors. The closest private residential wells to the site showed no tritium above natural background levels. A sample of water from a pond 50 yards north of the plant property line showed tritium levels of about 2,400 picocuries per liter, above background levels but less than one-eighth of the federal drinking water limit. The residential and pond test samples were taken with the consent of property owners and the results received on Dec. 1.

"The underground pipe that passes near the monitored site in the past has carried water containing tritium from the plant to the Kankakee River, where it was periodically discharged under federal guidelines as part of normal plant operations. No tritiated water is currently in the pipe and no tritium is currently being introduced into the ground. Braidwood has not released levels of tritium that exceeded federal limits."

The licensee notified the NRC Resident Inspector, State and local agencies and has issued a press release.

REACTOR POWER OPERATION IN EXCESS OF OPERATING LICENSE CONDITION

"This notification is being made pursuant to Braidwood Station Unit 1, Operating License Condition 2.G, which requires a 24 hour notification to the NRC Operations Center for reactor power operation in excess of 3586.6 megawatts thermal (100 percent rated power), i.e., a violation of Operating License Condition 2.C (1)- Braidwood Station will, following this notification, provide a written report within thirty days in accordance with the procedures described in 10 CFR 50.73(b), (c), and (e).

"Braidwood Station, Unit 1 experienced a Feedwater temperature transient on November 18, 2004, which caused reactor power to momentarily increase and peak at approximately 101.2% as indicated on the excore nuclear instrumentation system. The duration that reactor power remained above 100% was approximately one minute. Subsequent to the event, a number of peer reviews were conducted to validate that power did not exceed 102%. The results of these reviews questioned the methodology used to determine the power level at the time of the transient. Industry was consulted regarding methodologies appropriate for power level measurement during transient conditions. At 1700 on December 2, 2005, an independent Exelon task force concluded, using a conservative methodology, that reactor power level during this transient did exceed 100% for approximately one minute and was limited to a peak of approximately 103.5% and that the appropriate reports, as specified in the Operating License, should be initiated.

"This overpower transient, caused by the loss of a Feedwater heater string, is bounded by the Feedwater design basis transient described and analyzed in UFSAR, Section 15.1.1, "Feedwater System Malfunctions Causing a Reduction in Feedwater Temperature, therefore, the event did not place Braidwood Unit 1 in an unanalyzed condition that significantly degraded plant safety. No safety limits were exceeded and there was no impact on the health and safety of the public. The licensee has notified the Resident Inspector."

The licensee notified the NRC Resident Inspector.

SAFETY PARAMETER DISPLAY SYSTEM (SPDS) FAILURE ON UNIT TWO

"At 0049 hours on 12/2/2005 the Unit 2 [safety parameter display system] SPDS system failed. The cause of the failure is under investigation and is expected to exceed 8 hours.

"ERDS remains operable but several points are not available. For example 23 of 58 ERDS points are unavailable while SPDS is out of service, The ERDS system can transmit the remaining points.

"Loss of Emergency Assessment Capability - A review of the ability of the Emergency organization to function without SPDS was performed. Alternate sources for many of the points in SPDS were identified and are contained on an Emergency Plan format in PICSY (plant integrated computer system). Those points not available from PICSY can be obtained from the control room. With these compensatory actions and the communications in place between the facilities, there will not be a major loss of emergency assessment capability.

"Since the Unit 2 SPDS computer system will be unavailable for greater than 8 hours, this is considered a Loss of Emergency Assessment Capability and reportable under 10CFR50.72(b)(3)(xiii)."

The NRC Resident Inspector was notified by the licensee.

* * * UPDATE (Gordy Robinson verbal notification to Joe O'Hara at 0719 EST on 12/2/2005): * * *

" As of 0530 EDT on 12/02/05, Unit 2 SPDS was restored to Operable status following replacement of the CPU Board for the Remote Data Concentrator (RDC). NRC Resident was notified." R1DO (Todd Jackson) notified.

AGGREEMENT STATE - ABANDONED WELL LOGGING SOURCE

The following information was received from the State of Louisiana, Department of Environmental Quality, via facsimile:

"Precision Energy Services abandoned two sources in Well Logging operations. The logging tool was initially stuck on December 2, 2005 and abandoned on December 7, 2005. A 20 Ci source of Americium-241 (Beryllium) and a 2 Ci source of Cs-137 were abandoned at a depth of 6197 Feet. All abandonment procedures were followed. Deflection devises and cement were filled to a depth of 5902 Feet."

Louisiana Event Report ID Number: LA 050010.

THIS MATERIAL EVENT CONTAINS A "CATEGORY 2" LEVEL OF RADIOACTIVE MATERIAL

Category 2 sources, if not safely managed or securely protected, could cause permanent injury to a person who handled them, or were otherwise in contact with them, for a short time (minutes to hours). It could possibly be fatal to be close to this amount of unshielded radioactive material for a period of hours to days. These sources are typically used in practices such as industrial gamma radiography, high dose rate brachytherapy and medium dose rate brachytherapy.

Although IAEA categorization of this event is typically based on device type, the staff has been made aware of the actual activity of the source, and after calculation determines that it is a Category 2 event.

Note: the value assigned by device type "Category 3" is different than the calculated value "Category 2"