Explain the concept of 3Rs and waste management hierarchy?
What is the aim of integrated solid waste management program?
Bring out the difference between a natural attenuation landfill and an engineered landfill.
Explain the important details required for deciding landfill site.
Discuss in detail the multicriteria method for landfill site selection.
What is the importance of waste characterization?
What are the factors influencing leachate quality and quantity?
How to estimate leachate and gas generation rate?
With a neat figure, explain a conceptual liner and cover in landfill.
What is the major role of soil in a waste containment facility?
What are the requirements of compacted liner?
Explain in steps the design philosophy of waste containment liner system.
Starting from the basics, derive the differential equation for defining contaminant transport for reactive contaminant. Every phenomena governing differential equation need to be discussed in detail.
With neat figures, explain laboratory method for establishing a) hydrodynamic dispersion coefficient, b) retardation coefficient, c) diffusion coefficient of unsaturated soil with low water content d) partition coefficient.
What are the major differences between physisorption and chemisorption?
Explain the batch method for establishing sorption characteristics of the soil-contaminant system.
Explain the physical significance of sorption characteristics and its importance in contaminant transport modeling.
What are the different isotherms used for establishing sorption characteristics?
What are the different contaminant transport phenomena?
What is diffusion and when it is expected to dominate contaminant transport phenomena?
What is retardation coefficient and how it is helpful in determining ionic velocity?
A column test was conducted to determine dispersion coefficient. The soil used was a silty clay with specific gravity 2.7. The diameter and height of the saturated soil column is 5 cm and 7cm, respectively with a water content of 35%. Calculate the pore volume of the soil column. An advective flux equal to 0.003 kg/day/m² of 1000 mg/l SrCl₂ has flown through the soil column for 5 hrs. Determine the total pore volume and number of pore volume for 5 hrs. The longitudinal hydrodynamic dispersion coefficient is 1.267 x 10-9 m²/s with a tortuosity coefficient of 0.7. The molecular diffusion coefficient of Sr⁺² is 7.9 x 10^-10 m²/s. Determine the longitudinal dispersivity for the soil-contaminant system.
A batch test was conducted for 3 soil samples A, B, C with an initial concentration of 100 mg/l of SrCl₂. 5 g of each of the soil sample is mixed with 50 ml, 100 ml, and 250 ml of SrCl₂ and the values of Ce for A are 10, 8 and 6 mg/l, for B it is 12, 10 and 8 mg/l and for C it is 4, 3, 2 mg/l respectively. Compare the reactivity of the soil-contaminant system of the three soils and comment on the role of liquid to solid ratio on the sorption capacity of the three soil. Make any suitable assumptions.
Specific discharge in the field is given as 1.68x10-8 m/s. Bulk density of fully saturated porous medium is 1.6 g/cc with volumetric water content of 0.4. Partition coefficient of lead obtained by linear isotherm is 10 ml/g. Determine average velocity of lead. What will be the velocity of lead if it is assumed as non-reactive with porous medium?
A drainage pipe became blocked during a storm event by a plug of sand and silty clay as shown in figure Q3.1. When the storm ceased, water level above ground is 1 m. Permeability of sand is 2 times that of silty clay.
1. Obtain variation of head components and total head for the length of drainage pipe
2. b) Calculate pore water pressure at centre of sand and silty clay
3. Find average hydraulic hydraulic gradient in both soil plugs.
Determine the quantity of flow and seepage velocity for constant head set ups given below (Fig. Q3.2) in SI units.