Unfortunately, I was unable to embed this timeline into this page, so you’ll have to leave to take a look. But it’s my attempt to lay out the whole history in one place.
ACID MINE DRAINAGE
A simple, and simplified, view of how acid mine drainage works:
Naturally-occurring acidity and metal loading. Whenever discussing acid mine drainage, heavy metal loading, and mine-related pollution, particularly in a place with geology like that in the Silverton Caldera and Upper Animas River Watershed, one must always remember that before any miners set foot in the area, the streams were already tainted. Cement Creek always ran orange from time to time, thanks to the iron hydroxides that are so abundant in the local geology, and lower Mineral Creek probably always ran milky green thanks to naturally-occurring aluminum. Fish never would have been able to live in those stream segments and never will, regardless of how thoroughly mine-related sites are cleaned up.
One study, conducted by Durango hydrologist Win Wright for the US Geological Survey, found that some natural springs, that had not been affected by mining at all, were highly acidic (low pH) and heavily loaded with toxic metals. The following graphs are from that study. Look closely. The first one shows that natural springs can be more acidic than nearby mines. The second shows that some springs contain higher concentrations of iron and aluminum than mine drainage. And the third says the same thing regarding zinc.
This natural acidity and metal loading has often been used as an argument against cleaning up mines. Why spend all that cash on cleanup when you’re still going to have toxic water entering the streams and hurting the bugs and the fish? Why purify the water from the Gold King and the American Tunnel if you’re just going to dump it into the murky, always-toxic Cement Creek?
Here’s why: It’s not about Cement and Mineral Creeks, and it’s not about achieving some elusive “pristine” state of water quality, it’s about reducing the overall metal loads in the Animas River. If you remove 300 pounds of zinc per day from water dumping into Cement Creek, you’re also removing that 300 pounds from places downstream where fish do survive, and will benefit from even incremental improvements in water quality. Another thing to consider is that these naturally-tainted springs have very low flows in relation to many mines, so the actual volume of metals emanating from them is relatively low.
Knowing which springs are naturally acidic and metal-loaded is important, because it helps scientists formulate a picture of what pre-mining water looked like, and therefore they know what can be achieved by remediating mines. It also helps them decide which mines to focus on.
The placement of the American Tunnel and Sunnyside Mine workings, in relation to the Gold King, is crucial to understanding how bulkheading — or plugging — the American Tunnel may have affected the drainage from the Gold King. These diagrams will help readers with the latter chapters of River of Lost Souls.
GOLD KING MINE PHOTOS
DURANGO SMELTER AND URANIUM MILL
CARBON (a.k.a. MOVING) MOUNTAIN
The peak and mean flows of the Animas River have been slowly declining over the past century and a half. Does that mean we won’t ever see another flood like the one that tore through the region in 1911? These streamflow figures are from the Durango gage in the middle of town.
SLIME WARS and MINE TAILINGS
The “Slime Wars” may have ended in the San Juan Mountains, but they rage on in other parts of the nation and the world on a far, far bigger scale. Some of the worst mine disasters in recent decades — catastrophes that make the Gold King spill look puny — have involved tailings dam breaches. The United Nations Environment Program put out a report in December 2017 looking into this issue. It’s disturbing and important reading. Below are a few of the graphics from the report that help give an idea of how enormous the problem is.