From the standpoint of uranium enrichment capability, the Qom plant appears to be relatively small. It is capable of holding only about 3,000 spinning centrifuges.*
Due to its size, it makes more sense if it is simply part of a larger archipelago of plants, according to Gary Milhollin, director of the Wisconsin Project on Nuclear Arms Control.
If there are more secret enrichment plants, Iran could move more quickly towards a nuclear arsenal, Mr. Milhollin noted.