Alright, so here goes nothing. The shop I work at is in a cluster of at least ten other buildings, all owned and rented out by one man and, presumably, his wife. Our shop fronts the highway, with one to each side and one directly behind. We had a rather large(or at least I thought it was) problem yesterday in which the septic backed up and chaos ensued. We found out later that our shop and the one directly behind it use the same tank. I'm unsure of said tank capacity, but I do know it's right at the edge of the concrete pad the shop is built upon. Turns out the gentleman who just rented the other shop turned on the water and left, not realizing that this left a toilet running wide open all day. The water flowed through the toilet and into the septic....all day. Technically, shouldn't each shop have its own large capacity septic tank? Said shops are in a county jurisdiction, and sometimes certain things get a blind eye turned to them.