Module 3: Control, Reconnaissance, and Field Survey - Worked Examples

A client spreadsheet lists four corner coordinates but does not identify datum, projection, zone, control source, or how the coordinates were produced.

Before setting parcel corners, a crew checks its GNSS setup against two independent known points in the same declared reference frame, projection, and metre coordinate system. For this fictional training project only, the written specification requires each horizontal residual to be at most $0.030$ m. This value is an illustrative project requirement, not a universal DENR or NAMRIA tolerance.

An expected rear corner lies under dense tree canopy beside a concrete wall. The rover repeatedly loses initialization and produces inconsistent positions.

A monument is observed twice after independent rover reinitialization. The second position differs from the first by 0.012 m east and 0.016 m north.

A crew sets on verified control point A and backsights verified point B before observing property evidence.

A site prevents direct observation of two rear corners from the GNSS control. The crew runs a total-station traverse through the parcel.

A concrete monument is found near the expected front corner and appears undisturbed.

A found monument is about 0.60 m from the office-predicted location while the rest of the parcel appears consistent.