It seems that's the same bay as for Petropavlovsk-Kamchatsky, which with a population of 180,000 is Kamchatska's largest city. So this is very close to what amounts to a large population for Kamchatka. The Russians have always been cavalier about pollution and, as much as it may be hard to believe for some Americans, even more cavalier than here in the US. Not the Russian people of course but their political systems…
Well the western US is generally considered to be a delicate arid ecosystems that is really easy to mess up permanently. A lot of it was really messed up from timber cutting, mining, and cattle ranching in the 1800's.
And it only looks like it's recovered because no one remembers what it was like before. There is a valley where the Mormons found a rich verdant prairie. And of course they plowed it under and grew the best crop of wheat they ever saw. And the next winter the winds blew the topsoil away.