18-Env-A1 Principles of Environmental Engineering · May 2016
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
National Exams — May 2016 — 04-Env-A1 / Principles of Environmental Engineering. 3 hours duration; closed book with an 8×11 in double-sided aid sheet; Casio or Sharp approved calculator only. Any five questions constitute a complete paper (first five answers marked); all seven are solved below for completeness. Each question is worth 20 marks.
Reference texts. Davis & Cornwell, Introduction to Environmental Engineering (6th ed.); Metcalf & Eddy, Wastewater Engineering: Treatment and Resource Recovery (5th ed.); MWH’s Water Treatment: Principles and Design (3rd ed.); Guidelines for Canadian Drinking Water Quality (Health Canada); Canadian Council of Ministers of the Environment (CCME) water-quality and landfill guidelines; Canadian Environmental Protection Act, 1999 (CEPA); Impact Assessment Act, 2019 (Canada); Andrews, Canadian Professional Engineering and Geoscience (professional ethics).
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 3×3 table below cross-references each growth driver — urban growth (i), water use (ii) and industrial expansion (iii) — against the three concern areas the question specifies (wastewater generation, water treatment, mobile source emissions), giving two impacts and two engineering solutions in each cell.
| Concern Area | (i) Urban Growth | (ii) Water Use | (iii) Industrial Expansion |
|---|---|---|---|
| Wastewater Generation | Impacts: more combined-sewer overflow/surcharging; higher nutrient (N/P) loading from added connections. Solutions: sewer separation/CSO storage; tertiary biological N/P removal upgrade. | Impacts: higher per-capita generated volume; more concentrated loads in low-flow/drought periods. Solutions: water-efficient fixture mandates cutting generated volume; equalization basins to buffer concentration swings. | Impacts: process wastewater with metals/solvents entering the sewer; shock loading from batch discharges upsetting biological treatment. Solutions: mandatory industrial pretreatment program (sewer-use bylaw); equalization + continuous effluent monitoring. |
| Water Treatment | Impacts: greater peak-day demand straining plant/distribution capacity; higher turbidity/organics from impervious-surface runoff. Solutions: staged capacity expansion + demand-side management; source-water protection buffers + enhanced coagulation. | Impacts: source depletion (aquifer drawdown, reduced baseflow) concentrating contaminants; higher chemical/energy demand to treat larger withdrawn volumes. Solutions: tiered pricing/demand management to curb withdrawal; water reuse/reclamation to offset new supply. | Impacts: raw-water contamination risk from spills/cooling-water discharge near the intake; competing demand for process/cooling water. Solutions: source-water protection zoning + spill contingency planning; industrial water reuse/closed-loop cooling. |
| Mobile Source Emissions | Impacts: more vehicle-km travelled raising NOx/PM/VOC; worsened congestion increasing idling emissions. Solutions: transit-oriented development + active-transportation infrastructure; signal synchronization/congestion pricing. | Impacts: emissions from water-supply infrastructure construction/pumping; extra delivery trips in under-served growth areas lacking piped supply. Solutions: energy-efficient VFD pumping on a low-carbon grid; piped-network extension displacing tanker delivery. | Impacts: heavy-duty freight traffic raising diesel PM/NOx; fugitive VOC emissions from industrial fleets/loading. Solutions: low-emission/electrified freight and idling bylaws; rail/intermodal freight shift to cut truck-km. |
