Byron Nuclear Generating Station - Safety

Safety

As of the second quarter of 2007, Byron Nuclear Generating Station scored in the "green" in every NRC inspection category but one. The NRC has four levels of inspection findings, the levels are color-coded and the colors equate with risk levels. Green inspection findings represent very low risk significance. Higher levels, from white, to yellow, to red, show increasing levels of risk. For any inspection findings greater than green, the NRC conducts follow-up inspections. Unit One scored "green" in every category, while Unit Two scored "white," a step down from "green," on the inspection of the heat removal system. The inspection covered several other significant areas, including unplanned scrams, the alert and notification system and the emergency AC power system. From 2001–2005, no inspections of Byron Nuclear Generating Station found any condition that merited a greater than "green" designation, during the same time period inspection found 71 green conditions at the Byron plant.

Byron, like most U.S. nuclear plants, has been the subject of various actions by the NRC. Escalated Enforcement Actions represent one type. From 1997–2007 the Byron plant has received five such actions, two of which resulted in a total of $150,000 in fines. A $100,000 fine was issued on February 27, 1997 due to problems with excessive silt build up in two separate locations at the Byron facility; the NRC fined the plant $50,000 for each problem. The NRC levied an additional $55,000 in fines in October 1997 when the plant failed technical specifications surveillance guidelines. Specifically, they violated rules that require the Emergency Core Cooling System (ECCS) pump casing and discharge piping high points be vented once every 31 days. The potential safety consequence of the violation affiliated with the second fine was considered "low." As of 2007, the last NRC Escalated Enforcement Action against the Bryon Station came in 2005 when an engineer deliberately falsified surveillance reports to show he had completed work that was incomplete, though the plant could have been fined up to $60,000 the NRC chose not to impose the fine.

A small fire occurred at the plant on the morning of February 24, 2006. The fire was confined to the Unit 1 Refueling Water Storage Tank (RWST) heater. Initial attempts to extinguish the fire were unsuccessful, following those attempts a breaker was opened and the heater was allowed to deenergize which extinguished the fire. Units 1 and 2 were operating at 100%, but neither reactor was shut down as a result of the fire. As a result of the fire the plant declared an "unusual event," the least serious of the four categories of emergency declarations by the Nuclear Regulatory Commission.

On January 30, 2012, the Byron Unit 2 was shutdown and depressurized after suffering a power outage affecting power generation at the unit. Steam was vented from the non-nuclear, secondary side of the plant to aid in the cooling process while the turbines remained offline. A small amount of radioactive tritium was released into the local environment during the initial venting procedure, but was deemed no threat to the public by the Nuclear Regulatory Commission.