18-Env-B5 Industrial & Hazardous Waste Management · May 2016
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Reference texts: Nemerow & Dasgupta, Industrial and Hazardous Waste Treatment, 2nd ed.; Metcalf & Eddy, Wastewater Engineering: Treatment and Resource Recovery, 5th ed.; Davis & Cornwell, Introduction to Environmental Engineering, 6th ed.; LaGrega, Buckingham & Evans, Hazardous Waste Management, 2nd ed.; CCME, Guidelines for the Management of Biomedical Waste in Canada (1992); Canadian Environmental Protection Act (CEPA), 1999; Basel Convention on the Control of Transboundary Movements of Hazardous Wastes (1989); Canadian Nuclear Safety Commission (CNSC) regulations on radioactive waste; provincial hazardous waste regulations (e.g. BC's Environmental Management Act and Hazardous Waste Regulation).
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) On-site collection and treatment — a dedicated on-site leachate treatment plant (biological treatment for organics, followed by physical/chemical polishing for metals and residual colour) before discharge. (2) Collection and haulage/discharge to a municipal wastewater treatment plant — leachate is collected, stored and either piped or trucked to the municipal sewer under a discharge permit, relying on the municipal plant's existing treatment capacity. (3) Leachate recirculation — pumping collected leachate back into the waste mass (a "bioreactor landfill" approach), which accelerates waste stabilization and gas generation while reducing the net volume requiring off-site management, though it must eventually be balanced against a final treatment/discharge step as the leachate strength changes over the landfill's life.
