Morning Report for January 11, 1999
Headquarters Daily Report JANUARY 11, 1999 *************************************************************************** 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 JANUARY 11, 1999 Licensee/Facility: Notification: Northeast Utilities MR Number: 1-99-0003 Millstone 3 Date: 01/11/99 Waterford,Connecticut 1/8/99 SRI PHONE CALL Dockets: 50-423 PWR/W-4-LP Subject: UPDATE CONCERNING SMALL UNMONITORED RELEASE OF RADIOACTIVITY INTO NIANTIC BAY Reportable Event Number: 35219 Discussion: As previously reported in morning report 1-99-0001, a small amount of radioactivity was inadvertently released into Niantic Bay from the Unit 3 "A" waste test tank (WTT). The leak occurred when a 3/4" instrument line froze, and subsequently thawed, allowing leakage past a pressure instrument's damaged O-ring and gasket. A berm, which was constructed around the WTT, failed to keep the leakage from reaching the yard drain system, and eventually Niantic Bay. Although the licensee had a permit to release the contents of the WTT to Niantic Bay through an authorized and monitored release path, the leakage through the yard drain system, which is an unauthorized and unmonitored release path, was reportable to the State of Connecticut. Independent NRC assessment of the licensee's analysis and dose projection confirmed that there was no actual health and safety consequence associated with this leak. Based on the licensee's measurements of the concentrations of radionuclides in the WTT at the time of the leak (predominately tritium, with trace concentrations of other radionuclides), and conservative assumptions with respect to dilution and exposure pathways, the NRC confirmed that the dose projection to a maximumly exposed individual was 0.000000219 millirem whole body, and 0.00000207 millirem organ. The regulatory limit specified in the licensee's technical specifications is 3 millirem whole body in a year, and 10 millirem organ in a year. In comparison, the average United States individual receives about 360 millirem whole body per year from background sources. Accordingly, no on-site or off-site radiological risk is expected from this event. Regional Action: Routine Resident Inspector Followup. Contact: Richard Urban (610)337-5271 John White (610)337-5114 _
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Page Last Reviewed/Updated Wednesday, March 24, 2021