Castle completed a $1.4 million earthwork and site utility scope for the construction of a $101 million mixed used development. The 1.53-acre site includes 237 apartments, subsurface parking, and street-level retail and restaurants in the downtown business district of Clayton, MO. The site required mass excavation, storm, water, and sanitary lines, and site and utility demolition. Castle also performed structural excavation for the concrete contractor.  

In order to install a new downstream defender drainage system more than 20 feet deep, the Castle team used a slide rail shoring system prior to the installation. The slide rail shoring system helped protect the deep excavation as work was performed adjacent to an historic building.