OK, a bit of recap for those interested.
Plan A involved my homebrew water drill. 1st 12 ft went in readily using constant water and 20lb sledge. Unfortunately, operator error and I bunged up my screw in connection. Used backhoe for next 6 ft section, which should have brought me to edge of drive. Even digging foot or so under the concrete did not expose the end. Finally gave up and pulled out what I could, but 1st 12 ft remain in the ground.
Plan B a modification, mainly using power of the backhoe to push (pull) pipe, this time starting from other end. Note able to have a continual water connection using backhoe
Cottage John fabricated a cutter for lead end. Would rotate clockwise with large pipe wrench periodically.
Basic tool, but in 4ft lengths. Post pounder fit over trailing end to exert bh pressure to both 3/4 pipe and 1 1/2 pvc.
Put in 4 sections (16 ft) from the undercut side of drive. Paid particular attention that guide sled was well aligned and level.
Attempt to drive 5th section resulted in bent pipe. Took a break, a bit of comfort in that section connection was still accessible and thinking I could possibly replace that 1 section or worst case pull back complete line. John arrived about then and I updated him. He asked if he could explore a bit with shovel as I prepped for above options. Less than 10 minutes later he exclaimed he found the end of pipe. It was about 6 inches in from my dig. PVC pipe maybe 1.5 ft short from where it needed to be.
Cleaned out clay around end, disconnected cutter piece and attached a hook to pull.
A length of chain and backhoe eased it to desired position.
Freed up exit end of 3/4 pipe and moved to other end.
3/4 pipe gently extracted from pvc sleeve. Water flush to clean out some dirt before inserting 1” poly. Expect plumber will replace with his own. I just wanted to make sure pvc was clear.
Now to apply those lessons to remaining line.
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