We have a septic tank clean-out pipe at our house, but it is under some large trees and I cannot get the TC in far enough to use the hose to dump. So, I bought enough PVC pipe to reach out far enough so that I can use the hose. The pipes were glued together and two L-shaped pieces placed on the pipes, one at each end and pointing in opposite directions. When not in use, I place this pipe on a stand made from 4x4's way in the back of my property. The septic clean-out has a screw-on lid.
This works fine for me, but my distance is only 25ft, not as long as yours is.