# Help needed for soil calculation

#### RapidRide2

##### LawnSite Member
I 'm a Newbie,,, I need to fill in where an above ground swimming pool once was and then seed. I am pretty sure a dirt hauling place could calculate this for me , however I would like to learn for myself.

The old swimming pool hole is 21' diameter and 8'' deep. Can someone give me the formula on how much dirt i will need. If possible show me how it's calculated so i can use the formula for future references???? Thanks in advance.

#### chris638

##### LawnSite Member
Come on, that's a high school math question, not a landscape question. Pie x R squared x Depth. That will give you cubic ft. and divide by 27 to get cu. yds.

OP
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#### RapidRide2

##### LawnSite Member
Come on, that's a high school math question, not a landscape question. Pie x R squared x Depth. That will give you cubic ft. and divide by 27 to get cu. yds.
Thanks,, I knew piex3.14 however i didn't know to divide by 27 to get cu. yds. That's why i put it in the starting a landscaping and lawn section. I guess that's what i get for wanting to learn something.

#### FATWEASEL

##### LawnSite Senior Member
Thanks,, I knew piex3.14 however i didn't know to divide by 27 to get cu. yds. That's why i put it in the starting a landscaping and lawn section. I guess that's what i get for wanting to learn something.
Pie means nothing unless its cherry or pecan or..um..well...okay, we won't go there, but anyway....pi IS 3.14. 'r' is radius, half the distance across the circle or in your case 10.5 feet. Approximately 22 cubic feet is needed. I'm sure you'll use every bit of a full yard (27 cubic feet) to account for settling.

Andy

#### chris638

##### LawnSite Member
One yard wouldn't even touch it. Try 8.5 yds. 3.14 x 10.5 x 10.5 = 346 x 2/3. = approx. 230 divided by 27 = 8.5 cubic yds.

#### FATWEASEL

##### LawnSite Senior Member
DOH!!! 'r' squared Eh, what do ya want at 4am?

#### Runner

##### LawnSite Fanatic
Don't forget to allow for settling, either. Not trying to be a smart alek, but the measure will be taken with raw soil, that is fluffed. You can allow about 25% for settling.

#### lawnpro724

##### LawnSite Silver Member
I 'm a Newbie,,, I need to fill in where an above ground swimming pool once was and then seed. I am pretty sure a dirt hauling place could calculate this for me , however I would like to learn for myself.

The old swimming pool hole is 21' diameter and 8'' deep. Can someone give me the formula on how much dirt i will need. If possible show me how it's calculated so i can use the formula for future references???? Thanks in advance.
Do you mean 8' instead of 8" deep? If its 8' and 21' around you will need 130yds of topsoil to fill it in. In case you don't know how much that is its 170ton.

#### paul vroom

##### LawnSite Senior Member
Go to the top off this page, there is a "free tool" tab. Go to the mulch and soil calculator. It works awesome.

#### chris638

##### LawnSite Member
I haven't seen too many 8' deep above ground pools?????????????????