Willie, I just installed 100' of Logstor pipe, 25' is sitting on the ground under a mobile home, the rest is burind about 5' deep in gravel. I just left it on the ground and have had no issues yet. My other line is a homemade one using 1" HyrdonX, insulated with 3/4" thick commercial closed cell foam(the grey stuff) wrapped with red Tyvek tape then run inside of 4 white PVC with glued connections. It is sloped into my basement so that if it leaks I will know right away. It's only a 40' run. I used separate runs for supply and return so that I could put new lines in if there was an issue. Everything is working great so far and I'm very happy with what I did. The homemade pipe ended up being close to the price of the logstor but I way overdid it and could have done it much cheaper.
Home Depot stocks the sewer pipe and is only $15 for 4", I think you can also get 5" at plumbing supply place if the logstor won't fit inside the 4" . The only reason I suggest putting it in sewer pipe is to stop rodent damage, the little frickers will chew anything.
I'm building a couple of houses near you. I just finished one on Petrolia Line and just about finished one on Bentpath Line.