Hey, they are just spark plugs ! Here in Canada they dump radioactive metals in Ontario lake and then proclaim that the beaches are safe to use. So, I guess in your case it was accident with truck carrying spare parts, LOL !
Quickly,get those new specs John,I counted 42 old spark plugs .Generations from now,whilst on his lunch break,an overworked Krasnovian Schlazbut will be strolling along an alluvial level and make the find of his life,in these discarded items.Who are we to deprive him of such pleasures.Whilst working in a storehouse near The Globe,I used to beachcomb on The Thames at lunchtime and made some amazing finds,clay pipes mostly,but condoms too.