i owned a two-man ground hog in my younger days, similar engine......no more......from here on out its a small bobcat or kubota (rental) w/ posthole digger if i have a lot of holes, and a digging bar and posthole digger if just a couple holes. its very very very easy to tweak the back w/ those ground hogs.....glad to hear you are still ambulatory.
if all yer heavy equipment guys are off site, perhaps its better (easier?, cheaper?) to wait and let pond fill, stabilize, monitor water chemistry (pH meters are relatively cheap), then add ag lime to water if needed?......lime experts?
