Problem 1 (Problem 11-1, pg. 594)¶
A contaminated site has been surveyed and a contaminated region $100~ft. \times 150~ft. \times 15~ft.$ was delineated. The average concentration of total petroleum hydrocarbons (TPH) in soil is $10,000~\frac{mg}{Kg}$
Determine:
- The total mass of contaminants at the site in kilograms. Assume the soil has a specific gravity, $SG _{soil} \approx 2.0$
- Estimate total volume of petroleum hydrocarbons released assuming 50% of the hydrocarbins are lost to volatization, biodegredation, and dissolution (report the answer in gallons). Assume the hydrocarbons were gasoline with a constant specific gravity, $SG_{\text{gasoline}} \approx 0.8$
- Estimate the residual saturation of the hydrocarbon-soil system. Assume soil porosity is, $n=0.35$
In [2]:
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Problem 2 (Problem 11-2, pg. 594)¶
A sampling program at a Supermanfund site indicated the following DNAPL zones:
- A pool of free phase DNAPL in a stratigraphic depression in an unfractured clay. The pool is 200 $ft^2$ in area and 5 $ft$ thick.
- A zone of residual DNAPL extending directly underneath an old disposal pit 100 $ft^2$ in area. The residual zone extends through the 5 $ft$ thick unsaturated zone and 15 $ft$ through the saturated zone until it reaches the DNAPL pool.
Supporting data:
| Residual saturation in the unsaturated zone: | 0.10 |
| Residual saturation in the saturated zone: | 0.35 |
| Saturation in the free-phase zone: | 0.70 |
| Average porosity in water zone: | 0.30 |
Determine:
- The total volume of DNAPL at the site
- The recoverable volume using ordinary pumping.
In [1]:
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Problem 3 (Problem 11-4, pg. 595)¶
Gasoline is found in a monitoring well with $SG=0.80$. A total depth of 6 $ft$ of gasoline is found in the well.
Determine:
- Estimated thickness of free-phase LNAPL in the formation.
In [4]:
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