A Little Mercury Never Hurt Anybody, Right?

May 17, 1983:

The U.S. Department of Energy declassifies documents showing world's largest mercury pollution event in Oak Ridge, Tennessee (ultimately found to be 4.2 million pounds), in response to the Appalachian Observer's Freedom of Information Act request.

In 1983, the Department of Energy declassified a report showing that significant amounts of mercury had been released from the Oak Ridge Reservation into East Fork Poplar Creek between 1950 and 1977. A federal court ordered the DOE to bring the Oak Ridge Reservation into compliance with federal and state environmental regulations.

This story claims that the actual pollution was more than an order of magnitude smaller:

For decades at the Y-12 National Security Complex in East Tennessee, mercury from making hydrogen bombs flowed into East Fork Poplar Creek.
After its atomic bomb making in World War II, the Oak Ridge plant began work in the early 1950s on different processes to separate isotopes of lithium. The goal was to selectively concentrate the lighter lithium-6 isotope for use in fusion-type weapons that became known as hydrogen bombs.
Mercury was essential and Oak Ridge historian Bill Wilcox said there were big releases.
Environmental scientist Mike Ryon said by the mid-80s the creek showed little sign of any life.
There are varying reports of how much mercury likely entered the creek, but it's estimated at somewhere between 240,000 and 280,000 pounds.
Since 1982 the creek has been posted as a hazard because of the mercury pollution and that is not likely to change anytime soon. But now lots of fish and cleanup efforts are ongoing.

Either way, that is comparable to a hell of a lot of compact fluorescent bulbs.