Actually the first commercial nuke plant was\is the
Shippingport plant (down the ohio river from Pittsburgh) built in ‘57.
Was.
It was shut down in 1982 and completely decommissioned by 1987.
http://www.eia.doe.gov/cneaf/nuclear/page/nuc_reactors/superla.html
http://www.fas.org/irp/imint/doe_shippingport_01.htm