If this is the single line from the house to the septic tank and it is only
18 inches deep it is worth a little investigating. In an area that the truck
will NOT drive over, dig down to the pipe. Be careful because 45 years ago a
lot of clay pipe was in use and it will be brittle. If the pipe is cast
iron, you should take care because stress can crack it and the 5 foot
lengths will add to its fragilness. If it is vitrified clay (glazed clay) it
can shatter under the load, do not let him drive over it unless you are
prepared to replace it. If the pipe is black fiber "No-Co-Rode" pipe, it
probably will hold up as it has a little bit of play. If the pipe is black
polyethylene, you will have no trouble. I cannot think of any other types of
pipe in use 45 years ago. If the best intentions fail, and whatever pipe you
have fails, you should be able to easily replace it with modern 4" PVC sewer
and drain pipe.

"Steve" wrote in message
...
Hi,

I need to take down a large tree in my backyard where the only way to
do it is either through a climber (very expensive) or by bucket truck
(much cheaper and I liked the owner). $2,000 vs $600

The main issue is that there is no way to avoid crossing the septic
system. Mine is about 45 years old.

I once heard you can't drive over any part of the septic system. What
he plans to do it to use ground protection mats to create a path to
the tree. He says it is not good to drive directly over the tanks,
but it would be fine to go over the pipes using these mats. In
particular this would be the pipe between the house and the tank (not
the leach fields). I estimate the pipe is buried only about a foot
and a half. He says that because of the round shape it can take a
great deal of pressure without breaking.

This is a site with mats like he is describing:
http://www.alturnamats.com/

Does this sound ok and safe to do or should I go the more expensive
route and get a climber?

Thanks,
Steve