1973 Map of Ryegrass Flat

About this map

The Idaho National Engineering Laboratory dominates this landscape on the border of Butte and Bingham counties, serving as a high-technology industrial installation in the desert. The 1973 survey records a specialized infrastructure of research and containment, including the Auxiliary Reactor Area and the Water SPERT Tanks, or Special Power Excursion Reactor Test site. These facilities are linked by a formal grid of desert roads like Wilson Blvd and Fillmore Blvd, which contrast with the natural depression of Ryegrass Flat. This environment is characterized by the intersection of nuclear research and land management, where Industrial Waste Ponds and multiple Borrow Pits mark the earth near the Butte County line. The map provides a unique view of the laboratory’s footprint before later decommissioning and environmental remediation efforts changed the site’s layout.