The DDT is soluble in DMSO, so it is already possible to separate from soil.

The problem has been that the DDT isn't really useful, so you're still left over with DDT tainted DMSO. Hence, most cleanup efforts focus on sequestration of soil.

The electrolysis step creates benzene and other hydrocarbons, making a useful byproduct. This means there's a better incentive to treat it rather than store it.

So, you’re essentially washing the soil in DMSO, and DDT is more soluble in DMSO? — curious, what does it take to wash all that soil?