The Reactor in Cambridge's Backyard

It's been around for more than 20 years and no one has said a word about it. It's been a tool for medical, biochemical and physical research in Cambridge the whole time.

But since the accident at the Three Mile Island plant in Pennsylvania, more people have been calling the Massachusetts Institute of Technology (MIT) information office to find out about the nuclear research reactor at MIT in Cambridge's backyard.

A Wasteland

"We know that there's so much conservatism in this area, we do stop and ask ourselves safety questions again," Otto Harling. director of MIT's nuclear research laboratory, said yesterday. "We're not near the ragged edge at all as far as safety is concerned."

Harling said the MIT reactor studies beta and gamma particles themselves, rather than using them for energy, and its reactor produces only one-600th of the wattage of a commercial plant.

The cooling system, such a problem at Harrisburg, is not so crucial at MIT because the reactor there never gets that hot.

"Our core doesn't need pumps to cool it if we lose power for any reason. We do have an emergency water injection system, but the air itself surrounding it should be enough," Harling said.

The three-fold safety system causes problems of its own, though. "Anyone who's in charge of a reactor is sweating all the time trying to keep it running because there's so much redundancy in the circuits. Every time Cambridge power hiccoughs, we have to stop and check for a problem in our equipment," Harling said.

In fact, the core's products are cool enough to generate steam safely. Thomas Jones, MIT vice president for research, said yesterday the reactor body fills with hot but not scalding water. "The energy at that temperature isn't very useful, but it's very safe," he said. "In fact, if people had been energy-conscious then as they are now, we could have used the energy to heat these buildings."

Harling stresses that the system is hermetically sealed--even used-up fuel rods, which become highly radioactive waste, stay in the reactor core as long as possible to cool off.

When too many of these fuel rods pile up, though, they are moved to racks in a deep swimming pool for storage until MIT ships them to Barnwell, S.C., every year or so. The rods must be kept a certain distance apart to avoid a critical mass, which could set off a nuclear reaction. Reactor officials face a new problem since dump sites like Barnwell are increasingly hard to find.

A bill now before the state legislature would prohibit construction of similiar storage pools for radioactive waste.

And a Cambridge referendum if passed on the November ballot would request the state and federal governments not to license the construction or operation of any new nuclear power plants. But for now the anti-nuke furor hasn't reached MIT.