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At a guess, I'd say about 2 feet of snow or more and the rain layers are where again I'm guessing, it's rained and then frozen, with more snow on top, thus the frozen rain is as hard as rock.
They dug out 29 inches of snow on one of the greens, the green has no ice and is soft, then they have marked an ice layer from rain on 9th Jan and a 4 1/2 inch layer of solid ice at the top formed from rain on 29th Jan.
They do this to see how long it may take to thaw out once spring arrives.