The site of a warehouse expansion in Tampa, Florida was underlain by sand overlying limestone. The performance criteria required ground improvement to densify the upper sand in order to maintain a maximum total settlement of 25 mm (1 inch) for an applied subgrade pressure of 110 kPa (2300 psf). Considering the objectives, displacement grout columns were selected as the ground improvement technique. The efficacy of the displacement grout columns for densifying the upper sands was verified by a pre-production test program that included cone penetration tests and a large-scale plate load test.