Leaking problem for lube shop

On rainy days, we have problem with our pit getting some leaks around the walls. I have no clue where they may be coming from. But seeing that it only happens when rain falls, I thought mabye rain water might be sipping through some cracks and joins on the concrete pavement on either sides of entrance or exit.

I called few people to come and check it out, but not seem to have a solid answer.

Is this leak around pit walls a common problem? And what is the typical remedy?

More than likely it is just ground water seeping in through the block. I have a pit that was dug deeper than it was supposed to be and they hit the water table. It leaks all the time unless it hasn't rained in quite some time. Probally not much to worry about.

Make sure any grassy land around the building is graded so it slopes away.

I once owned a old lube in Florida with water leaking into the pit. Problem was shallow water table combined with inferior pit design and construction as well as having a clay-lined pond too close to the facility. Remodeling the sidewalls and floor was not cost feasible. My solution was to install a sump pump and transfer the water to the oil/water interceptor.

I managed a lube shop years ago - it had a small pit and a sump in the corner. There were no leaks when it rained - it was just there for spills or when the pit was washed down.