Drill, Baby drill.

Some oilfields in CA, the water that comes out with the oil is pretty much fresh, unlike the brine you usually get.  The benzene's just part of the petroleum spectrum that the water gets being in contact with the crude oil for millions of years. It usually measures, along with its buddies toluene, ethelbenzene, and xylene, in the tens of parts per million. Not much of that will get into your tomatoes. The heavy metals, on the other hand, along with the sodium chloride and calcium/magnesium carbonate, will build up in the soil until nothing will grow.

This just shows how desperate we are for water.