I am digging an adit through perma frost. Any body have suggestions as to the most efficient way to dig it. I have loaded it heavily with explosives, which did a decent job, but drilling is a major pain in the arsenal. The problem comes from the ground freezing behind the bit. I use a lot of water to keep the hole open for the cuttings and steel removal, but the water freezes on the floor, making an ever thickening skating rink. Mind you, this is at the portal and I haven't dug all the way through the frost yet. Been thinking about installing a hydronic loop to keep the ice down, so I can continue with the D & B program.