Facility/process review — obtain the plant layout, process flow diagrams and material balances for every production unit.
Water balance — account for every water input (process, cooling, wash-down, boiler feed, domestic) and every output (product, evaporation, discharge streams).
Identification of individual waste streams by source — locate and label each discharge point at the unit-operation level, not just the combined outfall.
Flow measurement — continuous or representative-period metering of each identified stream (and the combined flow, for cross-check).
Sampling and characterization — chemical/physical analysis of each stream (BOD5, COD, TSS, pH, temperature, specific contaminants).
Records review — raw-material usage, chemical purchase records, production schedules/rates, and existing monitoring data.
Personnel interviews — operators and process engineers often know about intermittent or batch discharges that a short-duration survey would miss.
Identification of waste-reduction opportunities — source reduction, segregation, recycling/reuse and recovery, evaluated stream-by-stream.
Cost data collection — current water, sewer-surcharge and waste-disposal costs, to support an economic case for any recommended change.
