An ultrasonic near-surface inundation testing (UNIT) device includes a soil cell device, a head tank feeding fluid into the soil cell and a reservoir tank feeding fluid into the head tank. The soil cell device includes a substantially planar base, at least one removable top plate with at least one pressure equalization port, at least one bottom plate, at least one sample chamber holding a soil sample, bender ports and a bender sensor pair. The base connects to chamber posts. The top plate connects to the chamber posts and has a cell inlet receiving fluid from the head tank. The bottom plate connects to the chamber posts and has a cell outlet passing fluid to the reservoir tank. The sample chamber, including at least one removable chamber plate, is located between the top and bottom plates. The bender sensor pair extend into the sample chamber through the bender ports.