This paper addresses foundation requirements to construct a new Geodetic/Geophysical Observatory at approximately five kilometers south of Matjiesfontein, in the southwestern Karoo. The observatory will host a Lunar Laser Ranger, Satellite Laser Ranger, and other collocated geophysical instruments, such as seismic and gravimeter stations, to be located in a specially designed vault. Field and laboratory tests and surveys show that the site is stable and capable of supporting the 5 ton weight of the Lunar Laser Ranger (LLR) structure that includes a one meter diameter optical telescope and mount to conduct laser-ranging experiments. The foundation requirements for auxiliary buildings and calibrating beacons required for the instrument and the envisaged experiments were also included in this study.