Attempting to remodel basement myself. I have removed a couple of non-load bearing walls to open up the space. I have come across a raised portion of the floor where I believe the original furnace was placed when the home was built (1961). This raised portion is about 2 ft x 3 ft and the poured concrete floor is sloped up the meet the top all the way around. The slope was created when the floor was poured and is not seperate from the floor so chipping it off is not possible. The "bump" is about 2 to 3 inches higher than the rest of the floor. Do I have to pour a new slab across my entire basement (costly) or can this "bump" be ground down and if so how?