In the 1970s, over 700,000 tires, held together by steel, were dumped off the coast of Florida to create an artificial reef. The steel later rusted apart, detaching the tires and causing an environmental disaster.
Before Chernobyl, the Soviets had another massive nuclear disaster which contaminated over 20,000 square km. The area was turned into a preserve to cover up the accident. The CIA knew of the accident, but also covered it up in order to protect the fledgling US nuclear industry from hysteria.
To preserve the harvest, Mao Zedong had all sparrows killed (along with rats, flies and mosquitoes) because they ate grain. The result was an ecological disaster that resulted in the birds’ natural prey devouring the harvest.
There is a lake in Russia that is so radioactive it can kill you within one hour if you stand near it.
Picher, Oklahoma is considered the most toxic place in the United States. The town has been ravaged by industrial mining; so much so that a majority of it’s inhabitants have fled and it’s current population is 20. There have been numerous reports of sinkholes appearing overnight as mine shafts collapse. Often, underground water, highly acidic and concentrated with heavy metals, come bubbling into these sinks and turns them into toxic ponds.