Odd Find For Drain Pipe

72chevy4x4

I was digging out footing for a concrete slab today and dug up a drain line-well at first it seemed to be the thin walled pvc storm drain line. After realizing it flows to the septic tank and doing a little digging, it comes from the washing machine drain line (concrete slab house). It comes out of the slab as a 1.5 (or 2") cast iron, then switches off to a 2.5" standard drain line via a concrete clump acting as the transition, then two feet later another concrete clump transition's to the 4" thin wall storm drain which leads to the septic.

Needless to say it's crap and I pulled it out and told the HO not to use the washer until I call back. Is it ok to thread a 2.5" pvc line inside the existing 4" thin wall that leads to the septic? Another question, can the drain line go through the wall of a monolithic concrete slab (extends 2' under grade and 12" thick on edges)? The cast iron is a little rusty-was it common to run this outside the house? I'm wondering if this use to drain into the yard and the previous HO thought it would be ok to rig whatever he had lying around. Is there recourse for a HO who finds garbage like this?

KillerToiletSpider

On slab septic homes, the underground is almost always run in the slab, and old cast iron is also rusty, it is the nature of ferrous pipe to be rusty. Hook a 4X2 mission coupling onto the cast and tie it back into the 4" line leading to the septic.

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The plumber

Thread pvc????? I'd put in a 4" combo turning toward the septic then a 4x2" combo turning toward the house. Put a 4x2 reducing bushing in the first combo/2" pipe and a 2" c.t to tie on to the two inch coming out of the house. 4" c.t on the other side of the 4x2 combo going to septic. This will let the plumber that comes out next week know it is 2" coming out of the house and 4" after the cleanout to the septic so they know what size blade to use. When you put the combos together it should make a u.

Add a 4" cleanout even if they have a 2" on the wall. If you've ever cleaned a 4" pipe with a 2" blade you know there's 50/50 chance you'll be back in 30 days to clear it again.

Driftwood

This may have been a grey water dump in the grass ! Drains run under the slab , and rise up insolated from the concrete.
Suggest You have the home owner bring in a plumber and get it permitted.
This could bit You !

72chevy4x4

I think it was a grey water dump and a previous owner rigged it up before selling it to the current HO (2 yrs ago). I looked up the pipe and it is "4 inch sewer and drain Coex solid". I'm not terribly familiar w/ sewer/septic practices, but is this stuff ok to use or will a plumber need to swap it all out?

Driftwood

Chevy,today I pull a permit in S F .Here it would be c .i. check with local bild. Dept. Sounds like You'll have inspectors on job. No sense pi$$ing them off, call a plumber. This is a tar baby for You ! Good luck Tool

The plumber

This would be the way to go. I wanted to say that, but I figured I'd give him a break. I'll bet the line has negative fall, it's probably not vented in the septic, and every joint is probably connected with concrete. This is the crap you run in to outside of city limits.
Call a plumber

neolitic

Think I'd make it a plumber with a backhoe, if there isn't already a hoe on the job.
Good luck.

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(Sorry....it seems there really are dumb questions)

72chevy4x4

I already have permits pulled for the addition and inspectors will be on the site-not trying to pull one over on anyone but do like to learn from experience regarding what is proper and not. The plumber is on his way-thanks guys!

Driftwood

You'll be working with these inspectors,You need Their respect and good will.