Hands-on proficiency setting up, operating, checking, and maintaining GPS/GNSS/RTK equipment, preferably Trimble, robotic total stations, levels, and field data collectors, including use of Trimble Access for control verification, point collection, 3D or model-based layout, stakeout, and line, grade, and elevation checks. + Develop and maintain site calibrations or localizations, control files, coordinate systems, digital terrain or elevation models, design surfaces, linework, and machine-control files needed to support GPS-enabled grade-control systems on excavators, dozers, graders, and other heavy equipment.