gradecontrol

Grade control is a term used to describe processes and systems that ensure the correct grade or ore quality is achieved in a given area. In mining, grade control refers to the ongoing collection and interpretation of geological data to guide daily production decisions, delineating ore from waste and maintaining alignment with design parameters. The practice uses drill core samples, blast-hole cuttings, face samples, trenching, and mapping, integrated with mine models such as block models or grade shells. Grade-control teams compare measured grades with plan grades and adjust short-term mine plans, blasting sequences, and equipment scheduling. Regular reconciliation compares actual mined material with model predictions to improve estimation accuracy over time.

In civil engineering and construction, grade control describes methods to manage surface elevation and slope to conform to design specifications. This includes survey control points, grade staking, and data from GPS, laser levels, total stations, or 3D machine-control software. Equipment such as GPS-enabled dozers and graders can automatically adjust blade height to maintain the designed grade while moving.

Benefits of grade control include improved accuracy, reduced rework, lower dilution, and better resource utilization. Challenges can include data quality and timeliness, calibration of equipment, and the need for integrated data management and communication among geology, surveying, and operations teams. Grade control approaches are selected to balance speed, cost, and precision appropriate to the specific project or operation.