Several years ago I built a 3 foot high x 24 foot long retaining wall with a stair case in the middle. This required me to dig 11" inches down for 6" of base plus 5" of the wall to be under ground. Compacting the 6" of base in the channel was back breaking because backing up the compactor and attempting to turn the compactor 5" below ground was nearly impossibe.
For a wall this high made of 5" High x 12" Wide x 9" Deep block, would hand tampering be OK?
Also, can leveling sand be used for a wall this high? I got the other wall straight as an arrow last time, but it took a full day just to lay the first course down.