The 200-acre West Lake Landfill Site is located at 13570 St. Charles Rock Road in the Earth City Industrial Park in Bridgeton, Missouri. It is surrounded by commercial/industrial and agricultural land on the eastern edge of the Missouri River flood plain. From 1939 to 1985, limestone was quarried on site. Beginning in 1962, parts of the site property were used for landfilling of municipal solid waste and construction debris. Two areas became radiologically contaminated in 1973 when soils mixed with uranium ore processing residues were used as daily cover in the landfilling operation. An adjacent property has also been impacted by erosional migration of radiologically contaminated material from the landfill. This property, known as the Buffer Zone or the Crossroad Property, was subsequently purchased by the landfill operator. It is considered part of the site and is enclosed within the site's perimeter security fence. Also located on the site is the Bridgeton Sanitary Landfill, which ceased operations in 2005. This sanitary landfill did not receive any radiologically contaminated soil.