One year later: Obama's EPA was "deeply sorry.". Karen Hudson-Edwards #Birkbeck, University of London.


05-05-2016 Nature-Science

(Photo: ‪#AnimasRiver spill 2015-08)

Twitter: @batchelorshow

One year later: Obama's EPA was "deeply sorry.". Karen Hudson-Edwards #Birkbeck, University of London.


“…There are many examples of historical and contemporary mine wastes posing threats to the environment. For example, in August 2015, waste water and tailings from the #GoldCreekMine flooded into Cement Creek and the Animas River in #Colorado, USA, turning them bright yellow. The spill was caused by the attempted remediation of historical mine wastes (7).

“Contemporary #tailings dam spills often affect river basins that have a legacy of historical contamination. On 25 April 1998, the Aznalcollar spill released ~4 to 5 million m3 of liquid and tailings bearing arsenic, copper, lead, and zinc to the Río Guadiamar in southwestern Spain (1). The tailings from the spill were removed from the floodplain during several cleanup operations, but later research revealed older contaminated alluvium underneath. As the river channel readjusted following the 1998 spill, this historically contaminated sediment was eroded and carried downstream toward #DoñanaNationalPark, a #UNESCO World Heritage Site (8).

“Perhaps the most infamous historical mine wastes are those in the Río Tinto Mining District in #Andalusia, Spain. Here, more than 5000 years of mining and natural weathering of the sulfide ores have created a strongly acidic (pH < 3) 90-km-long river that bears #arsenic, iron, copper, #cadmium, nickel, lead, and #zinc. Huge piles of waste rock have built up at its headwaters, and redand yellow-colored alluvium is found along its banks. Gross metal fluxes from historical wastes of the #RíoTinto Mining District have a substantial impact on global and local element fluxes: According to calculations by Braungardt et al., 8.1% of the dissolved zinc flux and 1.6% of the dissolved copper flux in global rivers come from the Río Tinto (9). Resuspended mine waste dust from the Río Tinto area supplies 32% of the antimony, arsenic, bismuth, cadmium, copper, lead, and zinc to the local atmosphere (4), although the mean composition of these elements is below the daily EU limit value of 50 µg m−3….”

Jul 17, 01:41 AM
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NCdad - 11 days ago

A superb program ! I really enjoy programs such as this where you interview experts in a field that concern us all but is seldom in the public limelight until a tradegy occurs. This should be part of everyone's education and not just learn of it only if one takes the course in college.