Cheaper suggestion....
Another, probably cheaper suggestion:
Aim a good-sized rock at it, or send a nuclear warhead.
Make a big hole.
See if the resulting crater looks more like basalt or ice -- should be some differences in morphology, and should expose some fresh ice if that's what under the dust.
If it appears to be ice, follow up with a Zamboni to clean all that dust off it it and make it nice and smooth.... :)
(A saturn V, by the way, has more than enough capability to place a Zamboni with soft-landing system on Mars. Or a nuclear-powered Winnebago. Just amazing how BIG those things were).