Bottom plate over interior drain tile
I used anchors similar to a "HILTI 3/8" X 3" HLC hex nut sleeve anchors" that I purchased from Home Depot when I finished my basement 10 years ago. The 3" size only went about 1-1/2" into the concrete and hold very well. I blew out the drilled hole and added a little silicone sealant just to be sure no water would come up the hole I drilled. Everything worked out well. If the PVC pipe is below where you will be drilling, that 1-1/2" to 2" deep hole should not come close to any drain pipe. This worked for me.