The sheer excavated walls were monitored weekly to verify that the wall surfaces hadn't shifted, which would be a safety concern for workers in the deep pit who are constructing the reservoir structure. The company used a Topcon GLS-1500 laser scanner to collect the data for the monitoring operations. With its portability and one-person operation, the GLS-1500 features an on-board data collector with an LCD display and a 21-key keyboard, which means it has the ability to function as a stand-alone laser scanner with no connection to a computer.