[Rockhounds] The Toxic Legacy of the Gold Rush

[Kreigh Tomaszewski]

It’s a beautiful, 60-degree day, the sky a cloudless blue. Spunn Road is
lined by stately houses looking down on the historic main street of
Jackson, California, the high peaks of the Sierra Nevada mountains visible
in the distance. There’s a slight bend in the road—and there it is. A
chain-link fence topped with barbed wired blocks access to a few
dilapidated buildings and a 50-foot-tall rusting steel structure that, in
another life, hoisted rock from the depths below. There’s a sign on the
fence: TOXIC HAZARD KEEP OUT.

Argonaut Mine is located in the middle of the literal Mother Lode at the
heart of California’s Gold Country region. It operated on and off from the
1850s until World War II. After that, the mine sat largely vacant as the
town of Jackson grew around it. Today, the only obvious remains are the
buildings and, visible across the valley, the remnants of the neighboring
Kennedy Mine, which just beat out Argonaut for the title of the deepest
mine in the state.

At Kennedy, the miners constructed an elaborate series of multi-story
wooden wheels one can still visit today to lift the mine waste, called
tailings, and dump it in the valley below. At Argonaut, they dumped the
waste—full of arsenic, lead, and other heavy metals brought up from
underground, as well as cyanide and mercury the miners added to help
extract the gold—a few blocks away.

>From the road, all that’s visible of the tailings area today is a large,
muddy vacant lot, marked by no more than a small sign on a flimsy-looking
fence. One can see where part of the fence was replaced last year after a
drunk kid plowed through it.

But the brown muck here is acidic and has average levels of arsenic, an
element that can cause cancer, diabetes, cardiovascular disease, and skin
lesions, of 400 parts per million. The level at which the state requires a
site to be cleaned up is 100 parts per million. John Hillenbrand, a
geologist with the Environmental Protection Agency, says he once recorded a
value of 90,000 parts per million. Mercury and lead levels are also well
above acceptable values.

https://gizmodo.com/california-gold-rush-abandoned-mines-toxic-superfund-1850428984