The message
from Broadback contains these words:

I have a lot of sleepers forming retaining walls, with this hot weather
they are exuding a thick tar like substance, which I assume is creosote.
Any ideas of an economical way of either stopping this of covering the
sleepers? The damned stuff gets everywhere working or walking by them!
I am not concerned about the EEC directive, just the mess.

I had the same experience with some very old ones, which hadn't been
treated for at least 30 years and still bubbled tar on hot days. We cut
ours to size with a chainsaw, and the tar goes right the way through. I
don't think you'll ever get rid of it.

Janet.