This project involved the abatement, demolition, enhanced reactor entombment, and site restoration activities at a decommissioned reactor site in Piqua, Ohio.   The first 45.5 megawatt, organically cooled and moderated, thermal reactor was built by the U.S. Atomic Energy Commission (AEC) as a demonstration project in 1963.  The Reactor Building consisted of an above ground containment dome that extended 68-feet high above grade, with a 44‑foot below ground portion that contained an entombed thermal reactor that was decommissioned in 1969. Northwest Demolition was contracted under our sister company (RSI), who managed the full scope of work, which included asbestos and paint abatement, universal waste, concrete work, demolition, and final site improvements.

The site consisted of two facility structures, a three-story Administration Building and the Reactor Containment Building (RCB), which housed the entombed reactor core and associated 8’ thick concrete ‘bioshield’.  After all interior components of the RCB were stripped out, the bioshield was encapsulated with waterproofing xypex concrete.  After the additional protective concrete was cured, the subgrade interior of the RCB was backfilled to grade before the containment dome and associated polar crane was completely removed by NWDD.  Reconstruction activities consisted of earthwork backfilling of the reactor hull and administration building basement, paving, and revegetation.