Problem with Batteries would be Acid contamination rather than
worrying about the lead. Leave the lead alone and it is fine.
Acid contamination can be neutralized with baking soda. Gasoline
is a solvent and travels everywhere underground. Lead from
batteries normally would have some value in salvage. Solution
to battery problem is to collect them and dispose/recycle of
them properly. You ought to see the problems we have with wells
and such here in the US cities from gasoline contamination from
gasoline stations. We have one waste site in town that after
pumping the contamination out for five years when they opened
the site the smell of gasoline was so bad that they had to
route traffic away from the site as it was a potential explotion
hazard. I do not deny hazards from cart batteries but it can be
controlled much easier than gasoline. Don't forget people have
to change oil in four stroke carts so here is another potential
source of pollution. With all due respect please stay all
electric please.