UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION
MR. VIRGILIO: Bob, good morning. It’s Marty Virgilio.
WANO – Good morning, Marty. I’m here with [omitted] is our Director of WANO Center, Atlanta and President of Operations at INPO.
MR. VIRGILIO: Good morning, – Good morning, Marty. How are you?
MR. VIRGILIO: All right, how are you?
WANO – Great. Marty, I got a call from [omitted] to give you a call, and your center, and share the information that we have. So, I’m ready to do that, if you guys are.
MR. VIRGILIO: Yes, please.
[omitted] – Okay, I’ll start, a lot of this stuff, you probably know from last night, but what we understand, the main issue is that Unit 1 at Fukushima, they had a station black-out, loss of all AC power offsite and the diesels, too.
As a result, they were using isolation condensers, an isolation condenser plan to remove decay heat from the reactor.
They reached the heat capacity limit of the suppression pool and as a result, that’s what drove containment pressures up, from what we understand, to about 120 pounds is the last psi, if the last information we had from last night.
At that time, dose rates in the control room went up about a factor of 1,000. Our experts believe that’s about 15 milli-rem per hour, but that’s very unconfirmed, and eight times higher at the site boundary, at that time, which was just barely above zero.
Portable electric is at the site. We believe they have batteries that are hooked up to run the DC systems and the isolation condenser. They’ve requested four emergency diesel generators, and they’re on their way.
[omitted] – Cont… – They’ve also successfully vented primary containment.
Reduced the pressures by over 50 percent.
And so, we’re not sure if that explosion was related to that venting or not, but we do know it was in the secondary containment.
When the explosion took place, we understand that the dose rate at the site boundary increased to 100 MR per hour, and then shortly after that, it dropped to 7 MR per hour.