Giving Compass' Take:

• Acid mine waste has become a big concern — but cleaning up this type of pollution is not easy or cheap. As Massive Science reports, new biotechnology innovations could provide the answer. 

• Are there ways to address the root causes of mining waste? Which research projects need the most support?

• Here's more on the role microbes play in cleaning our environment.

Staring down into the hollowed-out corpse of Parys Mountain, the rock walls are streaked in layers of vivid red, orange, yellow, and grey. Piles of rubble tower as far as the eye can see. Corrosive acid pools the color of dried blood drain into local streams. The abandoned mine has a poisonous legacy that stretches back 4,000 years – heavy metals have been extracted here since the early Bronze Age. Once the largest copper mine in the world, the site in North Wales stopped producing in the 1950s because it became cheaper to import copper ore from other countries. Abandoned for decades, it’s still one of the biggest heavy metal pollution sources in Britain.

This toxic landscape is the result of millennia of metal sulfide ore mining. The Parys ore deposit is an ancient hydrothermal vent field, layered with minerals containing a complex and rich metal content. Ores at Parys contain lead, zinc, and a whole host of other metals, in addition to the more usual iron, sulfur, and copper. When people dig into the ore in a mine, it’s exposed to oxygen and water. This starts a cascade of chemical and microbiological interactions that releases and dissolves the metals into water, making it extremely acidic as it flows out into the surrounding streams, soil, and nearby coast. Metal pollution from the water leaves measurable traces in sediments, plants, and and local wildlife.

Read the full article about toxic microbes and pollution by Rose Jones at Massive Science.