16-Civ-B5 Water Supply and Wastewater Treatment, May 2016: worked solutions

Paper format. National Examination, May 2016 — 98-Civ-B5 Water Supply and Wastewater Engineering. Three hours; closed book, one two-sided aid sheet and an approved calculator permitted. Question 1 is compulsory and the candidate attempts any three of Questions 2–5; every question carries 25 marks, so a complete paper is 100 marks. All five questions are worked here, because this set is a study resource rather than a timed sitting.

Reference texts.

Metcalf & Eddy / AECOM, Wastewater Engineering: Treatment and Resource Recovery, 5th ed. — activated sludge kinetics, secondary clarifier loading, nitrogen chemistry, sludge processing.
Crittenden, Trussell, Hand, Howe & Tchobanoglous, MWH's Water Treatment: Principles and Design, 3rd ed. — chlorine chemistry and breakpoint, granular media filtration, UV disinfection.
Davis & Cornwell, Introduction to Environmental Engineering, 5th ed. — water-quality indicators, hardness chemistry, sedimentation theory, residuals management.
Mihelcic & Zimmerman, Environmental Engineering: Fundamentals, Sustainability, Design, 3rd ed. — mass balances, reaction kinetics, nutrient cycling.
APHA/AWWA/WEF, Standard Methods for the Examination of Water and Wastewater — Methods 2130 (turbidity), 2340 (hardness), 5210 (BOD), 9222 (membrane-filter coliforms).
Health Canada, Guidelines for Canadian Drinking Water Quality; CCME, Canadian Environmental Quality Guidelines; Environment and Climate Change Canada, Wastewater Systems Effluent Regulations (SOR/2012-139).

Check: representative design data. Questions 1 to 4 are discussion questions and the source paper prints no numbers at all in them. Every number that appears in those four answers is a representative Canadian municipal value chosen by the solver so that each definition or mechanism can be made concrete and checkable; each is labelled where it is used, and all of them. Only Question 5(b) uses data given by the examiner. The graded content of Questions 1–4 is the reasoning, not the arithmetic.

16-Civ-B5 Water Supply and Wastewater Treatment: May 2016