Site Work Estimator Job Description. G.A. Peak Excavating, Inc. is seeking an experienced Site Work Estimator in the Bucks, Montgomery, Chester and Lehigh County areas. The Site Work Estimator must be able to perform various duties throughout the year. The Estimator is expected to use his/her experience to create project estimates and/or help facilitate projects by communicating with the field personnel, senior project management, and ownership. ...