It took me a while to figure out what was the nuke which blew up that close to Murmansk, but then I recalled the Soviets tried to use nukes to enhance mining speed. Needless to say, that didn't go so well.
As a result of those tests, there were certain health inspections on Northern Finnish people, and the dose of some plants was carefully monitored back then - I do believe they are still monitoring the worst fall-out areas, but it isn't considered a health concern any more.
Never understood the need to blow up perfectly good paradise islands with nukes, though.
And yes, the total was more than I thought it would be, didn't realize that there have been more than two thousand tests.