Pingo!!
What they are almost certainly seeing is a melted PINGO. In areas of permafrost (like most of Canada) the ice underground can form hills up to a 1000ft high. They are basically a big chunk of ice covered in soil.
If the temperature in the are warms enough, the ice melt and you end up with a crater full of water. You can see an almost identical feature here:
http://icecubicle.net/2010/03/24/phenom-pingos-of-the-far-north/
http://icecubicle.files.wordpress.com/2010/03/pingo-ice-lens-shattered.jpg