20 years ago they probably used rubber. Put rubber insulation on the
pipe(just the big one) If you want, you can dig under the pipe with a
claw hammer, gently. Or you can lift the pipe, gently and put the
insulation around the pipe. It isn't rocket science, Just don't be
abusive to the pipe. Reasonable care should sufice nicely. Don't
sweat it :-)

Stretch