Question 5 of 18: Five Steps for a Realistic In-Plant Waste Survey

Question 5: Five Steps for a Realistic In-Plant Waste Survey (5 marks)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

(1) Review the process flow diagram and plant layout to understand every unit operation and where water enters and leaves each one. (2) Identify and locate every waste-generating source — process discharges, cooling water, wash-down water, spills and leaks, boiler/cooling-tower blowdown — including intermittent and batch sources that a casual walk-through would miss. (3) Measure flow rates at each source and establish a sampling program that spans a full representative operating cycle (all shifts, batch cycles, and, where relevant, seasonal production variation), using composite rather than single grab samples wherever flow varies. (4) Analyze the collected samples for the parameters relevant to the plant's process and discharge requirements (BOD₅, COD, SS, pH, temperature, specific toxic constituents). (5) Compile a water/mass balance and report the findings, reconciling measured flows and loads against the plant's own water-use records to check for consistency before the survey's data is used for design.