http://www.cleanenergy.org/2011/02/01/epas-blind-spot-hexavalent-chromium-in-coal-ash/

SACE | Southern Alliance for Clean Energy

EPA’s Blind Spot: Hexavalent Chromium in Coal Ash

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A report from Earthjustice, Environmental Intrgrity Project and Physicians for Social Responsibility documenting the danger of hexavalent chromium form coal ash. ChromReport.pdf