Septic tank removal question....

[Richard]

House is maybe 10 years old. We added onto house last year which dictated our tank be 'moved'. Moved is defined as, caving in the original tank, filling it with concrete and simply installing a new tank maybe 40' away and redirecting the output from the house to the new tank.

My yard is a slope. Because of this, I do not have an even 12" or 24" of dirt over my old tank. It's more like I have 36" of dirt covering one end and 2" of dirt covering the other end (because of the slope of the yard)

The amount of dirt covering is not an issue for my question.

Today, the old tank has been pumped out, caved in, and filled with concrete and I think gravel.

There is a little #$(*&#_$#(@*& corner of it that is just below grade and I've been very annoyed with that.

got me thinking....

What are the pros/cons of simply digging up the old tank and hauling the pieces of it away & filling in the hole with dirt?

I would not have to remove 100% of the tank, just the upper couple feet so I could get more dirt between the remains and my grass.

 

[J_J]

I see no reason why you could not do that , if you want to. It will just be the effort , time, and money. Can you break up the walls yourself? Maybe a back hoe with a hydraulic breaker.

 

[jinman]

Richard, the only reason I can think of caving in a tank and filling with concrete is that it is probably what most of us would consider the easiest solution to ensure the void was safely filled, erosion will not occur, and we don't have to find a disposal location for the tank. If we all had Brutus to help, I think maybe we might just jerk that tank out of the ground and carry it to a location not likely to be a problem where we could crush and bury it. I don't see any problem with your removing it except to say that you will have to refill in a way that won't erode and you'll have another disposal job on your hands. Brutus will be happy to accommodate I am sure.

 

[WVBill]

What are the pros/cons of simply digging up the old tank and hauling the pieces of it away & filling in the hole with dirt?

I wonder where you would haul it away to. In today's world it might be considered "hazardous waste" (untreated sewage).

Sounds like a fun job with the backhoe, though.

 

[Topstrap]

By filling in with concrete do you mean after collapsing in the top they brought in a concrete truck and filled it with concrete or you mean they just collapsed in the top and left the pieces in the empty tank and then hauled in some gravel to fill in the rest? I install septic systems in Ohio and sometimes we just break the top and sides in and fill with limestone but usually not with a gravel which would hold water. They like us to try and break the bottom up so it won't hold any water. Most of the time if we can I try to dig out the old tank after crushing it in and haul it away and dump over a hill. We've never had a problem with it being called hazardous waste since the tank was pumped before crushing.

You should be able to uncover the top corner of the tank that you want removed and break it apart with a hoe since the sides are not very thick but the corner may be a bit stubborn so try to break it apart on the sides or end to get the corner to break off easier. If it was a 2 compartment tank it might still have the divider in it not completely broken up which might make it harder for you to break that corner off. I'm surprised that whoever crushed in the top when you added the new one did not do a better job of getting it all well below ground level. When they are close to the surface in the middle of summer that concrete heats up and will kill all the grass above it so we try to keep even new tanks at least a foot under ground on the shallow end and add another riser if needed.

Topstrap

 

[hitekcountry]

The new addition dictated the moving of the septic tank which leads me to believe that the old tank is too close to the new part of the house, and that would explain the requirement to fill it with concrete.
,,,Depending upon the distance,,, of the tank to the foundation, you may want to be careful what you do. If the tank is too close to the foundation, digging it out could weaken your foundation and cause all sorts of problems.

 

[MarkV]

The new addition dictated the moving of the septic tank which leads me to believe that the old tank is too close to the new part of the house, and that would explain the requirement to fill it with concrete.
,,,Depending upon the distance,,, of the tank to the foundation, you may want to be careful what you do. If the tank is too close to the foundation, digging it out could weaken your foundation and cause all sorts of problems.

Good point. I seem to remember Richard saying the old tank was near the foundation of the addition. I wouldn't dig if within 4' of the new footings.

MarkV

 

[Dargo]

Oh man, talk about bad memories. When I was in college (still living at home in the summers) I learned that you don't flush condoms down the toilet. I plugged up my parent's tank with them by flushing the....evidence. When the pump truck showed up and opened the one concrete lid, there they were, mostly floating right on top. Busted! To make a long story short, the pumping wasn't completely effective in removing all of them since they were stuck to a divider and outlet. I was told to go get them out by my dad. To see what I was in for, I laid down on the ground and used a flash light to look inside the tank. That's when the next concrete cover let go, right under my chest, and in I went.

Since the tank was in bad shape, the 'expert' pump driver suggested replacing the old tank. Yup, you got it. I spent the next day with an 8 pound sledge busting up that old tank and hauling it away a pickup load at a time. That's a job I'd really, really prefer to not do ever again. The sides are somewhat thin, but that 1/2" thick layer of, well, you know, made for a soft splatter on each hit with the sledge hammer. To say that doing such a job stinks is an understatement. If mine ever needs replaced, I'll either just fill it in or hire it out if it needs to be removed. Oh, digging out the field bed lines the rest of that week was no picnic either. Yeah, I had to dig them out too because my mistake plugged some of the lines. I also got to shovel out the nasty river rock that was around those old lines and replace all of it as well. In case you were wondering, my parent's yard is less than a half acre and they had no place to put the new system except where the old one was. Gees, that's been over 25 years ago now. If it goes out again now my dad will just have to pay someone else to do the job. I'm out on that deal.

 

[Bedlam]

Good to see you practiced "safe ***' LOL

 

[Richard]

I've had company for couple days... pardon the absence.

The new addition dictated the moving of the septic tank which leads me to believe that the old tank is too close to the new part of the house, and that would explain the requirement to fill it with concrete.
,,,Depending upon the distance,,, of the tank to the foundation, you may want to be careful what you do. If the tank is too close to the foundation, digging it out could weaken your foundation and cause all sorts of problems.

Actually, I think this was the main issue, being too close to the new foundation.

Although I do not remember any measurements, I DO think it had something to do with the footers. Mind you... the footers are uphill from the tank so the part of the tank nearest the footers is nicely under dirt. It's the part downhill that is annoying me.

I have recently added some dirt there to see what happens but since my yard is still messed up from all this, I've been wondering about "doing it right" (digging tank out).

I guess the real chances of me doing this are only 5%. I was wondering if it would be considered a hazardous material at worst... and if not, "icky" at best.

I forgot about the footer issue....that alone is probably decent reason to leave it alone.