This project will be a turnkey Design-Build (D-B) contract with all design and construction work being performed by the Contractor. The Contractor will provide all investigation, verification of site conditions and dimensions, design, research, travel, plant, materials, equipment, labor, instruments, tools, subcontractors, supervision, and management to complete all work required by these contract documents. The work in this contract shall include design and construction of a new 2-ply Modified Bituminous Membrane roof system to replace the existing Built-up roof assembly on the Ft. Gibson Powerhouse Roof, new roof drainage, as well as options for new guard rails and new roof ladders.