Construction Management and Water

Hong Kong Institute of Vocational Education

Department of Construction

Introduction of Environmental Engineering

Assignment 1: EIA, Construction Management and Water

Instruction: Answer question 1 and any other 3 questions on A4-sized single lined paper.

Deadline:

week 7 lecture

Q1. Briefly describe what construction management is, hence; briefly state how

EIA influences on the construction of a landfill project.

Q2. Define the following terms in relation to water engineering.

(a) Alkalinity

(b) Colour

Q3. The following test results were obtained from a wastewater sample taken

ata wastewater treatment plant.

Data:

 Wastewater sample size = 300 mL

 Weight of the filter paper = 1.2433 g

 Test results:

 Weight of residue and the filter paper after drying at 105oC = 1.267 g

 Weight of residue and the filter paper after ignition at 550oC = 1.259 g

Determine the concentration in mg/L of suspended solids and

suspendedvolatile solids. All the samples used in the solids analyses were

evaporated,dried or ignited to constant weight.

Q4. A water sample has a BOD5 value of 800 mg/L at 25oC. Calculate

theultimate BOD (Lo) of the sample. Given that the reaction rate constant

at20oC is 0.23 per day.

Q5. A BOD analysis was carried out. A wastewater sample of 30mL with a

DOof zero was mixed with 270 mL of dilution water with a DO of 10

mg/L.The sample was then put in the incubator for 5 days at 20 oC. The

final DOof the diluted sample and the diluted water were 4.0 mg/L and 9.2

mg/Lrespectively. However, it was discovered that the incubator was set at

30oCrather than at 20oC. Determine the 5-days BOD of the sample at

20oC.Given that the rate constant, k20, is 0.2d-1.

Q6. State the purpose of grit removal in wastewater treatment.