ROCKVILLE, Maryland — From the 17th floor of the Nuclear Regulatory Commission’s headquarters in Rockville, Maryland, Chairman Ho K. Nieh can see what he describes as a “memorial” to the nuclear energy renaissance that was expected in the early to mid-2000s, but that failed to materialize. 

It is a third agency building, just across the road, that was erected to support nearly double the number of employees than the commission has today, as regulators expected to see a flood of requests to build nuclear reactors across the United States.