Septic systems put in the old fashioned way...by hand. Middle, Charlie and I havin at it. Right is Mike, Charlie and Bedin laying blocks. Left is the end product, before it collapsed and we had to dig it and lay the block again. This time I convinced them to put in baffles for lateral support. I'm experienced in things collapsing...aka big culverts. Don't over load those wall..sheer stress i tell ya! Anyway we gotter done and moved on to hole number two behind the chalets.