My apologies...…... I'm glad you asked for more info on the machine. Here, I was in such a rush to post, I gave you the info on our other machine. The one with the tamper is Kobelco 140sr. Weight is around 33,000 lbs, and 93 HP.
As for the foundation.....Yes, they are claiming I caused some damage by operating the tamper within 2 foot of the corner, and there is indeed a crack in the floor in that corner. I was hoping to find other cracks in this floor, but unfortunately that didn't happen..... So much for the "Crack in every Bag" theory))), but its hard to say if that crack was there prior to my work.
The foundation was laid in 2014, and is a monolithic (s) style, where the parameter is 12" - 14 " deep, and the pad is 6" thick. This is not below the frost line in PA, but whoever did the job, it does look good. The only crack in the floor happens to be where I ran the tamper. The crack is in the 6" floor portion, but does not extend into the thicker footer portion of the pour. From the inside, the cracks forms a perfect Isosceles Triangle with the back and side walls.
The soil in this area is a medium to tight texture, with some clay and a little rocky. Drainage is pretty good. On a scale of 1-10, I'd give it a 8.
I hope my description makes sense.
Again, I apologize for the misinformation at first.
ps. Thanks for the "welcome"
This situation has been rather stressful, but I hope to become a familiar face around here.