Thanks JimI. We live on a hillside so the slope continues up...and down. Posts for the retaining wall were 18 foot treated 6x6 cemented in the ground about 3-4'. Backside of the wall that was trenched had about 2-3' space and left compacted native ground undisturbed as much as possible. Treated 2x6 were lag bolted from the trenched area side. Put 'deadmen' on each post by using a long threaded eye bolt through each post with the threads coming out the arena side. In the 'eye' side of the bolt we bent heavy 10' rebar to hold onto it and bent an 'L' on the other end and anchored in cement. That way, during normal settling, we can crank on the nut on the arena side to pull the wall back in some. Haven't needed to do this in awhile as I think it's pretty much settled into place. We also put some roofing felt in the bottom of the trench with drain pipe on top. Backfilled with drain rock. I tell you what though, when using those long treated posts, no matter how straight you put them in, once they started drying and sun gets to them, they really get twisted. Guess thats one of the problems of doing something yourself and tend to notice it more than someone else. Another thing to remember, we put the 2x6 boards in wet and butted up tight. This pretty much allowed for maximum swelling and avoided any buckling caused from it. When they dry out though, I can see some half inch gaps between the boards so be sure to allow for this. Anything else, just ask