Image of the Day: Toxic Sludge in Hungary Viewed from Orbit, 9 October 2010
Caption by Michon Scott
12 October 2010 On October 4, 2010, an accident occurred at the Ajkai Timföldgyár alumina (aluminum oxide) plant in western Hungary. A corner wall of a waste-retaining pond broke, releasing a torrent of toxic red sludge down a local stream. Several nearby towns were inundated, including Kolontar and Devecser, where the sludge was 2 meters (6.5 feet) deep in places. Four people were killed immediately, likely from drowning, and several more were missing. Dozens of residents were hospitalized for chemical burns. On October 9, 2010, the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-color image of the area. The alumina plant appears along the right edge of the image, and incorporates both bright blue and brick red reservoirs. The breach of the retaining wall is apparent. Sludge cut a channel through the northwest corner of the waste reservoir and spread onto nearby fields. The sludge forms a red-orange streak running west from the plant. The New York Times reported that the stream nearest the plant empties into larger rivers. The BBC reported that authorities were pouring plaster into the Marcal River in hopes of preventing the sludge from reaching the Danube River. The red sludge is a byproduct of refining bauxite into alumina, which is used in the manufacture of aluminum and other products. The World Wide Fund for Nature (WWF) suggested that heavy metals in the sludge could soak into the ground and be absorbed by vegetation, potentially causing environmental effects for decades. In the short term, the sludge swept away cars, filled homes, swamped agricultural fields, damaged bridges, and forced hundreds to evacuate.
