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right size of excavator for septic tank replacement

coolcatman1

Active Member
Joined
Aug 27, 2009
Messages
27
Location
aurora colorado
my parents are going to have to replace their septic tank soon and i am going to do the excavation what size hoe will lift the old tank out of the hole and unload the new tank off the truck and set it in the hole without problems? i may have to re do the leach feild as well but we don't know yet
 

special tool

Senior Member
Joined
Jun 15, 2008
Messages
878
Location
Bethel, Ct.
Well - you have a few considerations...What is the width for your fields?For example, we need to be 2 feet wide in some places and 3 feet wide in others near me.

What size is your old tank?
A 1000 gallon heavy duty weighs almost 12,000 pounds.
Then you have to dig around it and affix the sling....
As for tank setting, usually in an accesible area, the tank comes on a boom truck ready to drop into your PERFECTLY PREPARED hole.

A 200 (or Cat 320) is always a good compromise.;)
 

dozerdave

Well-Known Member
Joined
Jun 18, 2009
Messages
182
Location
Philippines
Hi coolcatman1,

Any chance you could pump out the old tank and backfill it and leave the old tank in place.
 

DigDug

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Joined
Dec 11, 2005
Messages
577
Location
Maine
A 200 size machine is the answer to your question.

But... is it possible to pump out and crush the old tank on site? This can be done with a rubber tire backhoe , then have the tank co. set the new one in hole with there crane truck.

You may get by with a 120 size machine if your old and the new tank coming are a two piece tank.

You could use a mini excavator if your old tank can be pumped and filled with sand then dig a new hole close by and order a plastic tank.

Just some options.

Good luck , doug
 

Hendrik

Senior Member
Joined
Mar 5, 2009
Messages
1,232
Location
Adelaide South Australia
Might pay to get a professional in, remember lifting a septic out of the ground is going to tougher than you think. Even though it may weigh X amount, the suction effect is going to increase that.
Then you have to consider that an ex will lift a fair bit in close and down low but once the load is raised, swung away or rotated, things will not be same.
Have you any experience in sort of thing?
And remember to make sure that nobody is near the tank when it is lifted.
 

powerjoke

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Joined
Aug 2, 2009
Messages
1,125
Location
Missouri
Occupation
owner/operator/estimator/mechanic/grunt/ditchdigge
Might pay to get a professional in,

BEST REPLY HERE!!!!

there are laws in place and license's that are needed here in the states for stuff like this

Pj
 

powerjoke

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Aug 2, 2009
Messages
1,125
Location
Missouri
Occupation
owner/operator/estimator/mechanic/grunt/ditchdigge
sorry, I shouldnt have been such an A-hole on the last post, but to answer the Q' you can dig a entire septic system with a shovel if thats all you have and you have enough time, if your asking a Q' like this it kinda makes me wonder :confused:

Pj
 

Paul W

Well-Known Member
Joined
Jan 19, 2007
Messages
49
Location
Ackley, Iowa
Hendrik is right.... Get a pro. I install systems on a regular basis......Here's what I would do. Get tank pumped then lift lid off and fill tank with sand, plumb straight through the tank (you may have to break out part off the baffle to do this). Put lid back on. Now install new tank... Tank problem solved! Dont use a plastic tank, just asking for problems. Might be a good idea to check with your local Sanitarian to see if you can do this without proper licensing. Most areas require it....Or, hire a pro.
 

STC73

Active Member
Joined
Jun 12, 2009
Messages
30
Location
Oak View, Calif.
I do tanks quite often with a Cat 420D backhoe. I demo the tank in the original hole then remove it and haul it off. Then regrade the hole and stabilize the bottom with 3/4 crush. We had a Cat 314 mini-ex that was real nice to use for tanks and new lines. (It had the split boom) Ive also done them with a Cat 304 mini-ex and a Cat 287 track skid steer because of the lack of room. Had to demo the concrete tank and replace it with a plastic because the tank truck had no way possible to get even close.... But like the rest said watch yourself on permits, etc. I know your probably trying to save them money but it can end up biting them in the azz. good luck!
 

rino1494

Senior Member
Joined
Feb 21, 2006
Messages
831
Location
NEPA
If you must lift out the old one and set the new one, then a 200 size would be best. I have set 1000 gallon tanks with my 315, but it is a little hairy. You gotta be careful. If you use a 150 size hoe, I know that you will not be able to pick it off of the truck.
 

coolcatman1

Active Member
Joined
Aug 27, 2009
Messages
27
Location
aurora colorado
ok i was thinking a cat 320 i got a buddy that installs septic systems quite frequently and he is going to help so hes my pro but he said it would be cheapest if i did the excavation
 

95zIV

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Mar 11, 2006
Messages
795
Location
Cincinnati, OH
Occupation
RR Contractor Super.
You might want to check with your tank providers too. If you can get a truck to it then they might pull it out and take it away for you(for a charge of course). I did a couple of those when I delivered, just dig around the tank and make sure there is plenty of room to work around it. They'll also have the proper lifting devices too. Your buddy is right it will be cheaper if you do your own digging as long as you pay attention to your grades. As for permits and such I'd just go to the town offices and talk to the person in charge of that kinda work. A lot of places don't care who puts it in as long as a engineer will sign off on it, and that's where the cost will be is getting a engineer to design a system for you and then just follow the specs that they give you. As for machine size unless you get a two piece tank anything smaller then a 315 cat or equivalent is dangerous if you aren't experienced. A low profile or heavy duty tank can run right around 12,000. A standard seamless 1,000 is around 10,000 or so. Then you've got the lifting equipment and the height to make the pick.
 

powerjoke

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Aug 2, 2009
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Missouri
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I still havent figured out how in the hell any of you can give any advice yet!

is it plastic or steel or concrete? ,....how many gallon is it?

I have set 1250 gallon tanks with my Mini-Ex before. but they were plastic!

Pj
 

Willis Bushogin

Senior Member
Joined
Nov 6, 2007
Messages
855
Location
NC
Occupation
owner
septic system

You might want to check with your tank providers too. If you can get a truck to it then they might pull it out and take it away for you(for a charge of course). I did a couple of those when I delivered, just dig around the tank and make sure there is plenty of room to work around it. They'll also have the proper lifting devices too. Your buddy is right it will be cheaper if you do your own digging as long as you pay attention to your grades. As for permits and such I'd just go to the town offices and talk to the person in charge of that kinda work. A lot of places don't care who puts it in as long as a engineer will sign off on it, and that's where the cost will be is getting a engineer to design a system for you and then just follow the specs that they give you. As for machine size unless you get a two piece tank anything smaller then a 315 cat or equivalent is dangerous if you aren't experienced. A low profile or heavy duty tank can run right around 12,000. A standard seamless 1,000 is around 10,000 or so. Then you've got the lifting equipment and the height to make the pick.

Ive been doing septic system installations and repairs for almosr 15 years. I agree with most of the info here ESPECIALLY GET SOMEONE TO DO IT FOR YOU. I have tried twice to remove a tank, that was just 6 months old (different jobs) first came out with a lot of digging, the suction on the bottom was great, it took almost 4 hrs to get it out, the tank truck lifted it.
Second, we hooked the tank truck to it again and messed with it forever and when, it came out, it was in pieces. I never again messed with removing tanks, until I crushed them. The cost factor is too great, compared to the cost of the tank. I talked to my friends that are in the business and everyone of them said, dont try to remove the tanks, not worth it. If the permit calls to replace the tank, we do like others stated, crush it and fill it and dig a hole close to it and set it to the elevation required to the house plumbing. The tank supplier, will set the tank, then comes the drain field, HUMMMM
First time HUMMMMM
I was luckly when I stated and had a guy that worked for me, had 5 years experience and he taught me the ins and outs

Laser level, did I say laser level, yep, laser level
Most trenches are 3ft (some 2ft, some 18") 3ft trenches are best dug, with a 3ft bucket, it can be dug with anything smaller, but a pain. If its a rock system, have you got a sled to install the pipe and rock? Im hoping you are not going to say batter boards.
If you just happen to install the system and it fails to pass inspection (lets say there is no more room to install a system, then more than likely the property could be condemned) could happen. You cant dig a system up, fill it in and start over, its a soil thingee (in my area anyway)
OK, I could write forever, but save yourself a bunch of headaches, money, etc and get someone to install it for you. There is not that much profit it this, for you to rent all this stuff and try to do it yourself. The way we make money is
we own our own backhoe
we own our dump trucks, to haul rock for the system
we have the experience and can install it pretty fast

I dont know what kind of system, they are making you install, but in my area
(mostly sandy soil) a 1000 gal tank, Distribution box and piping, 3- 75ft lines, at least 18" deep, crush and fill old tank, the cost is about $3200.
This would take me about 8-10 hours to do, in best conditions.
Without putting a sharp pencil, to this, Im guessing the final profit would be around $500-$700 Final question, can you rent a machine, worry about the system not passing, hiring help, hire dump trucks, buy rock, buy supplies, etc.
for this amount of money. Its not a good gamble and Im not a installer that cares whether a homeowner installs his own system. But you asks the question and this is our replies
Good luck and sorry for the long answer
 

coolcatman1

Active Member
Joined
Aug 27, 2009
Messages
27
Location
aurora colorado
ok thanks i dont know if this has any influence on your answers to my question but my neighbor and ex boss has a dump truck and a 320 cat that he will let me borrow so cost on rental is not a factor the labor will be me my brother and my neighbor so that will cost me a few cases of beer :beerchug so thats what 50 bucks maybe plus diesel fuel is it still cheaper to hire someone and my freind that does septics systems will make sure its up to code before anything is buried
 

Willis Bushogin

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Joined
Nov 6, 2007
Messages
855
Location
NC
Occupation
owner
Not trying to sound like a Butt, but sounds like you have already made up your mind.
Did I tell you about the time I borrowed my friends excavator, mine was working. It run hot and cost me $5500 to have it rebuilt.
Im finished
Good Luck
 

95zIV

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Mar 11, 2006
Messages
795
Location
Cincinnati, OH
Occupation
RR Contractor Super.
This just goes to show how reading and comprehension are two different things:

sorry, I shouldnt have been such an A-hole on the last post, but to answer the Q' you can dig a entire septic system with a shovel if thats all you have and you have enough time, if your asking a Q' like this it kinda makes me wonder :confused:

Pj

No where in this post does he ask what can dig the hole. All he asks is, well read the post, comprehend it, and it's not that bad a question. It has been asked more then once on here and by people who have been in the digging business for years just never been involved in anything like this.

my parents are going to have to replace their septic tank soon and i am going to do the excavation what size hoe will lift the old tank out of the hole and unload the new tank off the truck and set it in the hole without problems? i may have to re do the leach feild as well but we don't know yet
 

Hendrik

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Joined
Mar 5, 2009
Messages
1,232
Location
Adelaide South Australia
ok thanks i dont know if this has any influence on your answers to my question but my neighbor and ex boss has a dump truck and a 320 cat that he will let me borrow so cost on rental is not a factor the labor will be me my brother and my neighbor so that will cost me a few cases of beer :beerchug so thats what 50 bucks maybe plus diesel fuel is it still cheaper to hire someone and my freind that does septics systems will make sure its up to code before anything is buried
Well ask your mate who does septics how much the bloody thing weighs, get your mate with the 20 ton machine to look up the load specs for the machine and work it out.

OK lets calm down, smash up the old septic and bury it, cart it off, recycle it in a garden feature, whatever and lets think about the new tank, which should have a weight rating. You can even ask the manufacturer and then you look up the manual for the ex and think about it. You can probably exceed the manufacturers rating by a little bit, as long as you lift up and move the truck and then lower and move it closer to the ex, wear the seatbelt. DO NOT ATTEMPT TO MOVE AN EXCAVATOR WITH A LOAD GREATER THAN THE MANUFACTURERS RECOMMENDATION.
Once the load is lower and closer to the machine it is safer, basically if the ex can lift it off a truck it can shift it close to itself but once again if you move the load away from the ex things change.
Basically I am scared because you are asking a question which is answered in the operators manual, this does not make me confident that you can do this job without an experienced hand guiding you. You say you have a experienced friend to help you? Why does this experienced friend not know what can and can't be done? Has this friend ever installed a septic tank this size?
I am not saying you can't do this but make sure that you think and plan it through carefully, having someone crushed under a septic tank is bad, very bad.
If you have doubts get a pro to help.
I do not want to discourage you from doing things but I also do not want to see you end up getting hurt or hurting others.

Oh yeah, I seem to remember someone saying that as a general rule an excavator can lift 20% of it's own weight safely but that could be a faulty memory?
And also remove any attachments off the ex, eg bucket, quick hitch or thumb.
 
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powerjoke

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Aug 2, 2009
Messages
1,125
Location
Missouri
Occupation
owner/operator/estimator/mechanic/grunt/ditchdigge
This just goes to show how reading and comprehension are two different things:

your right, below I have put the keyword in bright large letter's so maybe you wont overlook it this time ;)

No where in this post does he ask what can dig the hole. All he asks is,

you really dont know do you :beatsme

well read the post, comprehend it,

I did,.....did you?

and it's not that bad a question.

Lmao, yeah right

It has been asked more then once on here and by people who have been in the digging business for years

So.....your saying this hole mess could have been avoided if the OP had used the SEARCH feature :eek:

just never been involved in anything like this.

I can tell you haven't,


Just below is a copy of the OP, What do you suppose Excavation means?....you better google it before you reply because I bet your gonna get it wrong! how did you figure he was going to "re-do" the lateral field and get the tank out of the ground without penetrating the soil?

my parents are going to have to replace their septic tank soon and i am going to do the excavation what size hoe will lift the old tank out of the hole and unload the new tank off the truck and set it in the hole without problems? i may have to re do the leach Field as well but we don't know yet

Finally the OP said it was a 1000gal concrete tank and I assume he is talking about the OLD tank?, now a guy can give advice. where as if it were a 750gal steel tank(very likely, that's why it needs replaced) I still say you could get it out with a decent size mini-hoe. it punch holes in it and smash it up, drag it out, and as far as the offloading of the new tank.....all the concrete tanks I have ever bought has been set by the supplier, so again CoolCat shouldn't need a 50klb hoe tracking up mom and dad's yard, Kinda overkill if you ask me but I have to fix what messes I make in situation's like this.

Coolcat: Sorry for trashing your thread buddy, and it sounds like you have your situation figured out and I hope all goes well, Take and post pic's we all like pictures.

95: Dont be a butt-head lol

EDIT: something else I remember from many year's ago, there was a gas station that went out of business and a guy removed the tanks with a shovel and a garden hose ;) so the Mini-hoe is more than enough lol. has anyone ever tried to float a septic tank out of the ground?

PJ
 
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