How to seal HT pipes for cable entries?

Why don't any animals get in? They can crawl through the empty conduit, can't they? What speaks against expanding foam?

That's underground after all. No one finds the way ... If you want to be on the safe side, fill it with liquid mortar.

I would rather be afraid that I accidentally throw something in there.

If you want to be on the safe side, fill it with liquid mortar.

But I need a lot of mortar for that. Why not construction foam?

The animals chew through the construction foam…

Okay, then I will put in foam sealant and then liquid mortar on top of that. I don’t need to flood the entire pipe.

I would stuff in newspaper and then seal it at the top with only 1 cm of earth-moist mortar. In case of an emergency, it can then be quickly reopened without having to pull out the expanding foam.