Tank baffle replacement

My outlet baffle is ng. I know how to replace it with pvc fittings. The problem is the opening over the outlet pipe is to small for the fittings to get through. Can I make the opening larger or will the tank top crack?



Thanks Frank

Im not sure if your talking about the back where the outlet is or something else. However I do take a sledge hammer or large pry bar and chip away the edges of the outlet all the time to make a 3 in hole fit a 4 in PVC T. If you are wanting to mess with a lid it all depends on rather or not you have 2 man hole openings, 4 lids, or a heavy duty solid one piece top.

The top of the tank looks like it is part of the tank cast as one piece. There are 3 openings, the middle one manhole opening, and 2 smaller openings over the inlet and out let pipes. Would someone go in the tank to repair the baffle? Or could I just enlarge the opening over the outlet pipe? The top of the tank is about 6 in. thick. I'm not planning on going in.

Thanks Frank

I would first install a concrete anchor, in the tank part you need to cut out. Secure a strong rope to it, and tie other end of rope to a tree, or something else. This is to prevent the piece from falling in tank.
Cut the top out. I would use a concrete saw, and maybe impact masonary drill bit.
Wouldn't want to sledgehammer it.
I just replaced my outlet baffle, and installed one, that had a pullout, washable filter. Will help to keep solids out of leach field.
My tank had no inlet baffle, which caused the inlet pipe to get clogged by the scum layer.
I installed a PVC inlet tee, and down pipe (baffle)