Depending on the size of the chunks of concrete, you must expect long term settlement(years) when using "dirt". Sand will settle much quicker and give you a better idea on the amount of extra fill needed. You should always avoid "dirt", organics, silt and many clays if you expect a reasonable grade over a few months (with rain/snow) to get an idea of the amount needed to get reasonably level to invest in a lawn.
With the wrong fill, you could end up with a very long term maintenance problem to create a nice space with a level lawn.
Thanks Dick. This is what I was hinting at and I should have been more direct.
I also removed in ground pool last summer. Planted seed in the whole back yard and the grass is not growing well over the pool site but is everywhere else. Any ideas?
The fill may have been quite sandy (so the grass above needs much more watering) or too clay-ey (so the grass above gets waterlogged).
Did you apply fertilizer yet?
States can help recovery from hurricanes and tornadoes by not requiring due digence or prompt and timely correction of substandard conditions, and by providing continued liability insurance where companies drop homeowners.