By Christina B. Farnsworth. It's been used in war. It will soon be part of cell phone technology. And now Global Positioning Satellite (GPS) technology has utility for home builders too. Glenn Martin, vice president of project management for Standard Pacific Homes (North California East Bay division), is pioneering what may soon become business as usual.

Martin works with a grading contractor that uses a satellite technology grading control system called SiteVision, one of several systems available from Trimble Navigation.

Thus far, Standard Pacific has used the system in two locations: Sanctuary Valley in Fairfield, Calif., in the rolling foothills of Solano County, midway between San Francisco and Sacramento; and Montecito in Concord, Calif., in the foothills of Mount Diablo, the San Francisco Bay area's landmark peak.

SiteVision lessens the impact of heavy earthmoving equipment in such areas because the bulldozers follow an accurate GPS map displayed on a screen inside the cab. The result is grading that more closely resembles natural land contours.

The U.S. Department of Defense operates the GPS system and makes it available to other industries. A GPS receiver inside the bulldozer cab receives signals from several satellites. The information downloads to a computer that calculates the exact position in three dimensions within 0.1 foot (1.2 inches).

Martin is pleased with the system's speed and accuracy, and anticipates savings down the road.