Damage from Gold Mining in the Amazon – Madre de Dios, Peru

We used to think only big commercial mining operations could have a significant environmental impact.  These images gave us a schooling.  The cumulative impact from many small, artisanal mining operations can result in just as big a mess as a conventional open-pit mine.  As reported in The Guardian and captured on video by the Carnegie Institution for Science, mercury contamination from illegal and unregulated gold-mining sites in the Madre de Dios region of Peru is flowing downstream and polluting the water sources that indigenous people depend on:

Aerial view of many small-scale artisanal gold-mining operations in the Madre de Dios region of the Peruvian Amazon. Source: The Guardian.

A Landsat-8 satellite image taken in April 2013 clearly shows the landscape disruption associated with mining activity, spanning an area over 11 miles long and up to 4 miles wide. Sediment-laden runoff in this area of high rainfall (it is a rainforest, after all) is rushing uncontrolled into adjacent rivers, coloring them pale muddy brown:


Landsat-8 satellite image taken in April 2013, showing landscape impact of illegal gold mining operations and sediment-laden runoff in adjacent rivers – a harbinger of the mercury contamination affecting indigenous people downstream. Intact forest is dark green. Land cleared for agriculture or by logging is pale green.


Measurement of the area impacted by mining; this does not include adjacent areas of deforestation (pale green) that probably indicate rapid settlement and farming accompanying the influx of miners.

Stepping back a bit, a higher-elevation view clearly shows the downstream transport of sediment — possibly contaminated with mercury — from the mining area:

Vertical overview of mining area and downstream transport of pale brown sediment (north is to the right in this view).


Panoramic view toward the north, overlooking the active gold-mining area (foreground) and showing sediment runoff downstream. Landsat-8 satellite image taken in April, 2013.

Landslide at Bingham Canyon Mine – Satellite Image

The spectacular landslide that shook the earth at the Bingham Canyon copper-gold mine in Utah on April 10 has been captured in an equally spectacular high-resolution satellite image taken on April 18.  The image below is a humble reduced-resolution version; to see the real thing in all it’s lovely detail, check out this week’s WorldView Report from DigitalGlobe:

High-resolution satellite image taken April 18, 2013, showing landslide in Bingham Canyon mine near Salt Lake City, Utah. Source: WorldView Report from DigitalGlobe.

This issue of WorldView also has an image of the fertilizer facility — and surrounding neighborhood — near Waco, Texas that was leveled in a deadly explosion, caught here on a cell-phone video.  Watch this in full-screen mode to get a feel for how catastrophic this was — and maybe a new appreciation for the lifesaving value of good zoning laws.

Landslide at Bingham Canyon Mine, Utah

If you haven’t seen photos of the massive landslide that struck Utah’s Bingham Canyon copper-gold mine on April 10, check out the story and accompanying photo gallery at the Deseret News, and these spectacular photos at the Kennecott Utah Copper page on Facebook.


Aerial shot of landslide in Bingham Canyon copper-gold mine near Salt Lake City, Utah. Photo courtesy Kennecott Utah Copper via Facebook.

Happily, nobody was hurt in this astonishing incident; mine operators had plenty of warning this section of the pit was failing. But some of the massive mining equipment was damaged, and mining activity was halted for a few days.  Check out these giant mining trucks, looking like scattered Matchbox toys under the pile of debris:

Mining trucks partly buried by landslide. Photo courtesy Deseret News.

Here’s an aerial overview of the mine and landslide.  The mining pit is about2-1/2 miles across at it’s widest, and more than half a mile deep:

Aerial view of landslide. Photo courtesy Deseret News.

I’ve attempted to re-create the view above using the pre-landslide imagery in Google Earth:

Pre-landslide view from Google Earth.

Stepping back a bit, it’s interesting to see how close this mining operation is to residential neighborhoods on the western outskirts of Salt Lake City; especially the 9,000 acre (14 square mile) tailings impoundment located on the banks of Great Salt Lake about 15 miles north of the mining pit.  Earthworks details some of the environmental problems and public health risks in this brief report [PDF].

You can explore this area with high-resolution imagery from 2010 in Google Earth and Google Maps.  And here is a super-detailed view of the area that failed from Bing Maps — maybe you mining engineers out there can identify the fault or other structural weakness that lead to the failure.  Let us know if you see anything interesting!

North is to the right in the pre-landslide Google Earth images below:


Panoramic overview of the Bingham Canyon mining operation, looking west. Salt Lake City suburbs fill the lower third of the view. Great Salt Lake at upper right.
Vertical view from 2010 imagery showing the active mining pit.


Vertical view from 2010 imagery showing the 9,000-acre tailings impoundment.  Note residential area at lower left, between SkyTruth logo and the impoundment.


Mining in Alaska – New Interactive Map

The folks at Ground Truth Trekking just released a nifty interactive map called Alaskan Hardrock Mining Exploration, showing the locations of active hardrock mines and hardrock mining prospects in Alaska.

Until we saw this map we had no idea there was so much potential mining activity across the state. You can read a lot more about that on GTT’s Alaska Metals Mining site.

Like our SkyTruth Alerts map, you can zoom in to a specific place and sign up to get an email when new hardrock mining activity pops up in that area of interest:


Oak Flat Land Exchange; Proposed Wasterock Storage Piles


I’ve been recently asked to demonstrate the visual impacts of some potential wasterock dumps in Superior Arizona. We’ve acquired the plans for the wasterock dumps. The plans were drawn by Golder Associates in 2010 for Resolution Copper Mining, a company pushing for the privatization of public land for the purpose of copper mining. So we did a little bit of research and learned about the proposed Land Exchange and Conservation Act. With the approval of this Act, Resolution Copper Mining will swap a portion of their private land in exchange for public property, including Oak Flat and Apache Leap. This land was set aside for public use by President Eisenhower in the 1950’s. It has become a well known place for climbing, hiking, and camping and is considered sacred by the local tribes. Anti-mining groups believe that the mining operation will likely destroy much of the area. It will also generate huge volumes of wasterock– earth and rock that is removed to get to the copper ore. Resolution is proposing to build a giant storage impoundment just north of town, to hold the wasterock.

Rendering of proposed Resolution Copper wasterock storage piles. Town of Superior Arizona at right.

Based on these plans, I have rendered a 3D model of the large (permanent) and intermediate (temporary) wasterock dumps using Google Sketchup. I then placed them in Google Earth. We’ve created an image gallery, illustrating how large the wasterock dumps are and what they might look like from various perspectives in town.