Much of it is in Arctic permafrost.
It sounds like the best place to use it is right where it is...The Great White North.
Extracting it may not be too bad, but transporting the ice and keeping it frozen could get costly.
Seems like you could stack it up like cordwood, right outside your igloo...or polar research facility. It would probably be a lot easier than hauling in propane.
I think the vast, vast majority is on the continental shelf in 1 - 5 thousand feet of water.
Not enough ambient pressure under the permafrost to stabilize it.