How much contaminant escapes through a barrier in 30 days?

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SUMMARY

The discussion centers on calculating the amount of contaminant escaping through a soil barrier used for waste cleanup. The soil has a porosity of 0.23, bulk density of 1.87 Mg/m3, and permeability of 9.6 x 10-8 m/s, with a hydraulic head of 1.8m. The contaminant concentration is initially 125 mg/l, and the partition coefficient is 25 l/kg. The solution involves calculating the mass of solids to the volume of water and utilizing a spreadsheet to model the contaminant escape over 30 days, focusing on discrete bed-volume transits.

PREREQUISITES
  • Understanding of soil properties: porosity, bulk density, and permeability
  • Knowledge of contaminant transport principles in groundwater
  • Familiarity with partition coefficients in environmental engineering
  • Basic spreadsheet modeling skills for data analysis
NEXT STEPS
  • Study the principles of contaminant transport in groundwater
  • Learn how to calculate mass transfer using partition coefficients
  • Explore spreadsheet modeling techniques for environmental data
  • Review "Earth Science: The Water Planet" by McGraw Hill, focusing on groundwater concepts
USEFUL FOR

This discussion is beneficial for environmental engineers, structural engineers involved in waste management, and students seeking to understand contaminant transport in soil systems.

Sadeq
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hi all
i am structural engineer, and i tok an environment course because the course options was limted
i have a question to solve but the problem i feel stupied because my back ground in this area is zero
so please help me
the question is

A soil has a porosity of 0.23, a bulk density of 1.87 Mg/m3 and a permeability of 9.6 x10-8
m/s. It is being used as a clean-up barrier 450mm thick underneath a waste deposit that covers 50 x 120 m plan area. There is a hydraulic head of 1.8m across the barrier. If the contaminant concentration in the fluid which passes through the barrier is, initially, 125 mg/l, calculate how much contaminant escapes through the barrier in 30days. The partition coefficient is 25 l/kg. Ignore diffusion and dispersion effects in this case and assume that the thickness of the barrier acts uniformly.
Hints:
1) you will (probably1) need to calculate the ratio of the mass of solids to the volume of water in the soil.
2) you may consider the flow through the barrier as being a number of discrete transits, each comprising one bed-volume which suddenly replaces the previous bed-volume, waits without moving for the length of time indicated by the transit time, and then is suddenly displaced by the next bed volume.
3) I suggest you work out the contaminant that escapes for the first bed-volume; then work out the volume escaping in the second bed-volume. After that you will be able to set up a spreadsheet-based solution for as many bed-volumes as you need.



please help me ,because i feel lost
 
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It's not within my comfort zone but it seems to be covered well in a textbook,
"Earth Science: The Water Planet" issued by McGraw Hill, chapter 3 Groundwater.

(Google hints)
 
Thank you very much.
I don't have an access for this book.
The main problem this not my major ,so please guide me

I will be thankful fro you for whole of my life