Happy birthday Three Mile Island
Thirty years ago this day at 4:00AM, the
reactor vessel at Three Mile Island suffered a coolant leak and subsequent partial core meltdown.
The thing to remember is that the safety system worked perfectly (the scram rods deployed and the reactor core was shut down, what happened was that the residual heat caused the low coolant level to react with the cladding on the fuel rods and there was an explosion of gas.
Although the inside of the containment vessel is still very hot, it is a "
containment vessel" after all and it did its job perfectly. There was a minimal release of radioactivity -- people in the surrounding area got less of an exposure than they routinely get when flying in a jet airplane.
One last thing to consider it that the accident happened thirty years ago. The reactor had been in operation for five years. At that time it took about ten years between the time that a reactor was planned and when it came online. That means that TMI was based on a design from around 1960.
Our engineering and technology has come a long way. At that time, each reactor was a brand new design.
Many companies now build standardized systems -- want 2,000MW? Use two of our 1,000MW cores. If something goes wrong with one of those standard designs, say a bearing on a pump fails earlier than predicted; you go through and overhaul those bearings on every single reactor out there. This allows you to isolate and eliminate potential failure modes on the other units.
Nuclear is the way to go -- tons of fuel out there, it is mature technology and a lot less polluting than coal.
Posted by DaveH at March 28, 2009 11:00 AM