The 1/10^th scaled Refractive Index Matched PebbLe bEd (RIMPLE) facility has been designed and partially constructed. The facility purpose is to study flow phenomena during a Pressurized Loss of Forced Cooling (PLOFC) and Depressurized Loss of Forced Cooling (DLOFC) accident scenarios in Modular Pebble Bed Reactors (MPBRs). The facility utilizes a 60% sodium iodide solution and 6.25 mm borosilicate glass balls for index of refraction matching. With the index matched between fluid and solid, high resolution imaging techniques like Particle Image Velocimetry (PIV) and Laser Doppler Velocimetry (LDV) can be used to image the flow in the pebble bed around the pebbles. Of particular interest is the flow fields in the bulk region, the wall region, at the interface between the pebble bed and upper core region, and in the upper plenum. The design and planned experimental campaign will be presented.