Growth, Industrialization, Urbanization and Energy Use: 16-Civ-A3 Elementary Environmental Engineering, May 2018, Q5

Question 5 of 7: Growth, Industrialization, Urbanization and Energy Use

Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)

Notes on this paper

Paper format. National Exams, May 2018 — 16-Civ-A3 Elementary Environmental Engineering. Three hours; closed book with one candidate-prepared 8½ × 11 double-sided aid sheet; approved Casio or Sharp calculator only. Seven problems are printed, each worth 20 marks, and any five constitute a complete paper (maximum 100 marks). All seven are solved here, because the set is intended as a study resource rather than an exam script. Section marks are shown in brackets at the left margin of each question and are reproduced from the final-page Marking Scheme.

Reference texts.

Davis, M.L. & Cornwell, D.A., Introduction to Environmental Engineering, 5th ed., McGraw-Hill — material and energy balances, reactor kinetics, hardness, disinfection, water and wastewater unit processes.
Masters, G.M. & Ela, W.P., Introduction to Environmental Engineering and Science, 3rd ed., Pearson — mass/energy balances on power plants, air-emission estimation, growth–pollution linkages.
Mihelcic, J.R. & Zimmerman, J.B., Environmental Engineering: Fundamentals, Sustainability, Design, 3rd ed., Wiley — sustainability, life-cycle thinking, environmental impact assessment, professional ethics.
Metcalf & Eddy / AECOM, Wastewater Engineering: Treatment and Resource Recovery, 5th ed., McGraw-Hill — wastewater unit processes and plant upgrading.
Crittenden, J.C. et al. (MWH), Water Treatment: Principles and Design, 3rd ed., Wiley — coagulation/flocculation, filtration, membranes, adsorption, disinfection.
Engineers Canada / EGBC Code of Ethics; Canadian Council of Ministers of the Environment (CCME) and the Guidelines for Canadian Drinking Water Quality (GCDWQ), Health Canada — professional duty and water-quality benchmarks.

Check: Problem 4(ii) quotes a rate constant as “20 dm⁶/mol²” with no time unit, and states the fundamental reaction 2A + B ⇌ C. It is solved as a forward-rate second-in-A/first-in-B rate law with $k=20\ \text{dm}^{6}\,\text{mol}^{-2}\,\text{s}^{-1}$ (the only reading that makes $-r_A=k\,C_A^{2}C_B$ dimensionally a rate); the time unit is taken as seconds per NOTE 1. Because no feed flow rate is supplied, the well-posed deliverable is the flow-independent space-time $\tau$ (with $V=\tau\,v_0$ for any stated feed basis), not an absolute volume.

Question 5: Growth, Industrialization, Urbanization and Energy Use (20 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.

The answer is organised in the required 2 × 3 matrix: the two rows are the media (water demand, solid-waste production), the three columns are the growth drivers. Each cell states two impacts and two engineering solutions.

Two impacts and two engineering solutions per growth driver
	(i) Economic Growth	(ii) Industrial Expansion	(iii) Energy Use
Water Demands	Impacts: higher municipal withdrawal, stress on source and aquifer drawdown. Solutions: water-conservation/metering + leak reduction; water reuse/reclaimed water for non-potable demand.	Impacts: large process-water withdrawal and contaminated effluent to receiving waters. Solutions: closed-loop recycling / zero-liquid-discharge; on-site pre-treatment to meet sewer-use and effluent limits.	Impacts: thermoelectric cooling-water withdrawal and thermal discharge. Solutions: closed-cycle (cooling-tower) or dry cooling; shift to renewables that need little/no cooling water.
Solid Waste Production	Impacts: more municipal solid waste and packaging; shrinking landfill life. Solutions: source reduction + expanded recycling/composting (diversion); extended-producer-responsibility and pay-as-you-throw.	Impacts: hazardous and process wastes, sludges and by-products. Solutions: cleaner-production / by-product exchange (industrial symbiosis); secure hazardous-waste treatment and manifested disposal.	Impacts: coal ash, scrubber sludge and spent materials. Solutions: beneficial reuse of ash (cement/aggregate); waste-to-energy / anaerobic digestion with residue stabilisation.

Topic. Drivers of pollution (economic growth, industrialization, energy use) and the engineering hierarchy of responses across water and solid waste.

Key relations. Waste-management hierarchy: reduce > reuse/recycle > recover (energy) > treat > dispose. Water hierarchy: conserve > reuse > supply-side augmentation.

Why this works. Growth scales withdrawals and waste generation roughly with activity, so the highest-leverage responses reduce demand and close loops at the source rather than enlarging end-of-pipe capacity; treatment and disposal are the last resort.

Common pitfall. Offering only end-of-pipe treatment for every cell; under strict requirements, source reduction and recycling are required first because treatment/landfill capacity is finite.

Source. Masters & Ela, growth–pollution linkages; Davis & Cornwell, solid-waste and water-resource chapters; CCME waste-diversion guidance.