NRC’s Jaczko Responds to Rep. Markey on the Sr-90 Issue at Vermont Yankee

It’s been a few weeks since I posted about Entergy responding to Rep. Edward Markey (D-Mass.) on the strontium-90 (Sr-90) issue at the Vermont Yankee nuclear plant. NRC Chairman Gregory Jaczko has since weighed in, on the NRC’s behalf, with a letter he sent to the congressman.

Of note, the chairman’s letter echoes what Entergy officials and the Vermont Department of Health (VTDH) have been saying all along:

Because there are multiple potential sources of Sr-90, including nuclear weapons testing by multiple countries in the middle of the last century, it is very difficult to draw conclusions about the source of any particular Sr-90 contamination that is found in the environment unless there is additional supporting evidence.

Because of this fact, Jaczko believes that Entergy’s Laurence Smith, manager of communications, is fair in one of his statements that “There is absolutely no evidence to suggest that Vermont Yankee is the source for the strontium-90.” He writes:

The quoted licensee statements in your question are not without foundation based on the above information.

The chairman also continues by explaining that the NRC’s methods of analyzing the data employ a somewhat different “band of uncertainty” than the VTDH, and concludes that:

The VTDH results are too close to the level of uncertainty to be considered by themselves a conclusive indication of the presence of Sr-90. When taken together, these factors lead us to conclude that there is no need for further study of possible Sr-90 contamination from Vermont Yankee at this time.

If there is ever an indication of Sr-90 releases above the legal limit or contamination at Vermont Yankee, the chairman reassures the congressman that the:

NRC will take action, as appropriate, at that time.

Given that the state’s department of health and the Nuclear Regulatory Commission have come back to the congressman with similar explanations, I wonder if we can now consider this issue to be null?

Read the full letter here.

Sunday Update

UPDATE AS OF 11:30 A.M. EDT, SUNDAY, APRIL 10:
Management of water continues to be a top priority at Tokyo Electric Power Co.'s Fukushima Daiichi nuclear power plant.

TEPCO has begun to install steel sheets and a silt barrier at the intake structure for reactor 2 to prevent further spreading of radioactive water that is leaking from the power plant, Kyodo news service has reported. Plans are under way to install similar barriers at other locations near the plant in an effort to contain contaminated water within the plant's bay. Last week, TEPCO used a sealant to block a leak from a concrete enclosure near reactor 2.

Meanwhile, 60,000 tons of contaminated water must be removed from the reactor 1, 2, and 3 turbine buildings and nearby underground enclosures, the International Atomic Energy Agency reported. The water will be pumped into the condensers of each reactor and into a radioactive water storage tank. TEPCO made room in the tank by discharging low-level radioactive water into the Pacific Ocean. TEPCO also has ordered temporary storage tanks for the site.

Injection of cooling water into reactors 1, 2 and 3 continues. Workers are spraying water into the spent fuel pools for reactors 1-4 as needed. TEPCO also continues to inject nitrogen gas into the primary containment of reactor 1. The nitrogen will prevent possible ignition of hydrogen that may be accumulating in the containment.

The utility is now using remote-controlled bulldozers and power shovels to remove radioactive rubble from around the plant. Operators are using cameras on the equipment and elsewhere on the site to control the equipment from hundreds of yards away. The rubble will be stored at the plant site.

The Japan education ministry is expected this week to release radiation exposure safety guidelines for school children in areas outside the evacuation zone surrounding the power plant, the Japan Atomic Industrial Forum reported. The guidelines will require schools to suspend classes, stop outdoor lessons, or ensure students wear face masks if radiation surpasses certain levels.