The reactor is expected to close to tours for at least the next two years to replace its roof and make other repairs and improvements to the 80-year-old reactor building.

The reactor is expected to close to tours for at least the next two years to replace its roof and make other repairs and improvements to the 80-year-old reactor building.

There were no precise construction blue prints and workers on the top secret project did not know what they were building, but B Reactor was completed and went critical in September 1944. The ...