ORP (Oxidation-Reduction Potential)

orp on a FieldMeasurement measures the electron activity of the groundwater — whether it is oxidizing or reducing. This is a purge stabilization parameter and an important geochemical indicator: negative ORP values indicate anaerobic conditions where certain contaminants are more mobile or degradable. Compliance staff monitor orp during purging to confirm stabilization and report it in long-term monitoring trend analyses to characterize aquifer conditions.