In the yard adjacent to my (new) home is a sewage pit. It appears that when the plumbing to the upper stories needed to be replaced (many years ago), rather than repairing properly, a hole was made in the cover of the pit to allow the pipe to drain into the pit.
Unfortunately the hole was made pretty large, and the bugs and smells are a problem.
This is a rough diagram of the problematic area:
blue = cover
red = vertical pipe
black = walls (some walls have windows)
green = open sewage
I can apply plaster/caulk to the open areas and edges, using wood or plastic to cover the larger areas, but that would be a nightmare if (when) access is needed.
How can I seal the hole (green area) without making access to the pipes difficult?