Which industry is listed as a source of industrial wastewater?

• A. Residential laundry
• B. Tannery
• C. Public park irrigation
• D. Municipal street runoff

Answer: (B)

Industrial wastewater comes from manufacturing and other processes where used water contains pollutants. A tannery fits this because it’s an industrial operation that treats hides with chemicals like lime, sulfides, and chromium salts, producing wastewater loaded with organic matter, color, and heavy metals. Domestic activities such as residential laundry generate household wastewater rather than industrial effluent; public park irrigation uses water for watering, not discharging process effluent; and municipal street runoff is stormwater that washes surface pollutants but isn’t wastewater from an industrial process. Therefore, the tannery is the industry listed as a source of industrial wastewater.