When vinegar is used as a herbicide, does it act systemically?

I am about to prepare a drainfield site (i.e. from our septic tank) for
planting with shallow-rooted ground cover. It is currently grassed, and
because of being a drainfield site (and also a front lawn!) the grass
grows luxuriantly and needs cutting every week. Shallow-rooted ground
cover will be much better, less demanding in terms of maintenance. So
the question is: how to kill the grass without harming or disturbing the
soil?

It seems the alternatives are spraying with Roundup (Glycosphate) or
spraying with vinegar. I would prefer to use vinegar because I
understand that the residue actually enriches the soil. However, if
vinegar doesn't work systemically we could find that new grass appears
from unkilled roots after the groundcover has been planted, and that
would be a problem.

I have read that traces of Glycosphate CAN still be found in soil two
years after spraying. This may disturb the delicate drainfield. It may
also retard the growth of groundcover. Also, our drainfield-lawn is on
a slope at the bottom of which is a line of hedge and bushes so if toxic
glycosphate residue remains in the soil for up to two years it may well
drift downhill in that time and retard the established hedge and bushes.

I would like to use vinegar on the grass, provided it has a permanent
effect on the roots.

Has anyone experience or knowledge of this?

Eddy.