In Operation LAC, US Army engineers sprayed St Louis with radioactive particles, biological, and chemical agents over the course of several decades to see how long term NBC and fallout damage affected civilian population centers, and the human body.

The sprayed a dangerous bacteria to mimic anthrax, zinc sulfide (highly radioactive), and various chemical weapons from planes, and from dispersal trucks parked on the downward slope of the mountain overlooking the city.

The targets were primarily schools, hospitals, elderly care facilities, and residential areas, as they contained the largest amount of targets.

This was part of a larger experiment as well. Other targeted cities include, San Francisco, Minneapolis, Corpus Christi, Springfield, Detroit, Toledo, Toronto, and Vancouver these are the ones the Army had admitted to as they covered up most of the operation.

Other tested areas include vague references to “All states east of the Rocky’s”, “Entire Mississippi delta”, “Native American reservations”, and “The entire Canadian border”.

They also covered the entire North Eastern coast of Britain.

I’m aware of a nuclear landfill, but that doesn’t sound as nefarious as all the other stuff here.