Adding dirt over septic tank/lines

[andrewj]

I had my septic tank installed before my grade was where I wanted it...Now I'd like to bring my grade up about 4 feet to the back door so I won't have a deck/porch...but that will mean placing an additional 4 feet of dirt agains the house, and sloping it downward toward the existing grade. It won't be enough dirt to cave in the concrete lid, but it will make opening the tank difficult if we ever have to do that.

The pipe to pump the tank - I can just extend that.

Anyoen see problems with my plan?

 

[Scooby074]

I dont see any problems as long your finished grade is under your house siding. It shouldnt have any effect on the tanks function.
Id just put a concrete crock with a cover over your cleanout hole. Seal the bottom face of the crock where it meets the tank with
tar, and seal around the inside where it meets as well. Dont scrimp with the tar.

Ive done this several times when i worked for a septic contractor.

EDIT: Assuming your system is similar to the ones we use here. Im a little confused about the pipe to pump bit. Do you not have an access plug on both ends of your tank?

 

[Skyco]

I don't understand the "pipe to pump the tank" bit. When I have mine pumped they open the access so they can move the pump truck wand around and get all the accumulated solids in the bottom of the tank.
Are you saying you have a fixed pipe in the tank for pump out? Seems like that wouldn't be a very effective method.

 

[LBrown59]

I had my septic tank installed before my grade was where I wanted it...Now I'd like to bring my grade up about 4 feet to the back door so I won't have a deck/porch...but that will mean placing an additional 4 feet of dirt agains the house, and sloping it downward toward the existing grade. It won't be enough dirt to cave in the concrete lid, but it will make opening the tank difficult if we ever have to do that.

The pipe to pump the tank - I can just extend that.

Any 1 see problems with my plan?

I got a similar problem .
My septic drain is about 10 to 15 feet to low down in a big deep hole I'm wanting to fill in.

 

[Lil_FarmerJim]

The pipe to pump thing is a pre-plumbed pump out. Rather than having to dig up the hatch to get to the tank some areas require that a pipe be pre-plumbed down into the tank to make it easier for the honey dipper to do his work and get out. Depending on how it was done can leave you with an odd looking loine white pipe sticky up in your yard.

As for all that additional soil on top of your tank, that would concern me. Generally, or so my buddy tells me, they don't like more then a foot or so of soil on top the tank. (For fear of collapse and ease of access.)

Jim

 

[Scooby074]

The pipe to pump thing is a pre-plumbed pump out. Rather than having to dig up the hatch to get to the tank some areas require that a pipe be pre-plumbed down into the tank to make it easier for the honey dipper to do his work and get out. Depending on how it was done can leave you with an odd looking loine white pipe sticky up in your yard.

As for all that additional soil on top of your tank, that would concern me. Generally, or so my buddy tells me, they don't like more then a foot or so of soil on top the tank. (For fear of collapse and ease of access.)

Jim

Interesting about the pump out,. I can see why they did it, but its good to be able to look directly into the tank and check the inlet and outlet and level. On top of that when it comes time to pump some times you got to stir the sludge from the bottom.

Not sure what code is anymore,but Ive seen upto 3' or so over the tanks here with no issue. I dont know if id go 4-5' though.

 

[skipro3]

When you get ready to fill in over your septic, pull the lid and add tubular sections to the hole in your tank. Septic dealers sell these tank lid extensions in sections of about 1 foot tall each. Stacking enough to put the lid about a foot below final grade is what you need to do.

 

[biggerten]

I used a riser to get mine above grade, here's a shot of my tank dug up so that I could insulate it, have had trouble with it freezing. I placed about 6" of loose styrofoam, followed by a layer of 2" rigid polyurethane sheet above the tank. I also cut disks out of another sheet of polyurethane, and glued them together to make a 12" thick 'plug' for the access hole.

 

[metalsmith]

As far as the line from the dwelling to the tank is concerned if its quality pipe such as schedule 40 even 10ft of cover is not a problem. For the tank several feet cover should not affect a concrete tank but as mentioned above use tank port extensions to bring the lids up to grade. You did not mention if a leach field is in the area of new fill, if it is check your local codes for maximum cover for the type of soil you have and do not exceed that. Leech fields not only wick water out into the soil but evaporates large amounts of water to the air. With to much cover you cut off that evaporation, along with reducing needed air into the field necessary for bacteria digestion. Both of these conditions will cause the system to overload and fail.

 

[jgrinn]

As Metalsmith stated: You have to watch how much fill you put over your leach field!!