A massive sludge flood caused by the rupture of a red sludge reservoir at an alumina plant in western Hungary has affected several towns near Ajkai, 100 miles (160 kilometers) southwest of Budapest. The sludge contains a highly toxic mixture of heavy metals. A Greenpeace team examined the causes of the toxic spill and its effects on the land, water, and air and have sent samples to two private labs for analysis. Parts of the town of Kolontár which had been evacuated is now open for citizens to move back to their houses, but the cleaning process is still not finished.