Another question I don't see answered in the article: is there any risk for existing life by heating a huge amount of dirt? Will at some point surface and possibly influence local weather / thermal winds? Or should I just get my tin hat off?
If the underlying stored heat leaks to the surface then it may indeed melt the snow and you'll have "snow-free" parking, but that won't be the end of the story, as all that resulted water will most likely turn your parking lot into an ice rink.
snow-free means you're losing heat to the environment vs keeping it contained. I would imagine if properly designed you could stand on top of the completed dirt pile without feeling any temperature delta with the air.