I really don't like the idea of making a weed killer
based on salt and/or vinegar!!!
Several years back someone posted on rec.gardens a
formula for "organic RoundUp". . . it was based on
salt and battery acid. Salt and vinegar is just a
variation of the same thing.
"Salting the earth" was a method of warfare used
by ancient Mediterranian empires to destroy their
enemies fields. It was effective but the idea is to
kill the weed - not to kill the soil.