Hydrogeochemistry of arsenic in an aquifer under an industrial site

We investigated an industrial plant located within the city of Bordeaux, Southwestern France: the superficial fill aquifer is contaminated by various chemicals due to the manufacture of the fungicide "bouillie bordelaise" (copper sulfate). The contamination by acid, copper and sulfate is most likely due to the industrial processes involved in the chemical treatment of copper and to the use of pyrite for the production of sulfuric acid. The presence of arsenic in the aquifer is assumed to originate from the use of low grade pyritic minerals for the production of this acid. The objective of the study is to investigate the mechanisms controlling the solubility and, therefore, the potential transport of arsenic in a contaminated aquifer.