Surveying the a monument system at Lawrence Berkeley Laboratory´s Advanced Light Source accelerator

Particle accelerators with demanding alignment requirements face a need for periodic re-surveying of their reference monument systems. At the ALS, significant foundation settling and the necessary relocation of some floor monuments mean that the entire system of over 100 monuments must be re-surveyed to an accuracy of 100 microns at two year intervals. Last Fall, the monument survey was conducted entirely by the in-house Survey and Alignment crew using a simplified instrument mounting system and an inexpensive commercial software package. Precision levels, plummets, theodolites, and an electronic distance measuring system were used with the innovative “Monopod” instrument mounting system in a cost effective approach to this critical task