Bottom line: there is a big problem with dumped, fueled reactors in shallow water.
To quote the article:
"Information now provided to the Norwegian daily Aftenposten by Russia’s authorities catalogue “enormous quantities†of Soviet-era nuclear reactors and radioactive waste dumped into the Kara Sea over the course of decades, far worse than previously known, and which include the experimental K-27 submarine that was eventually scuttled in 1981 once repairs to its liquid metal nuclear power plant were deemed impossible to complete".