Spanish chemists are helping to clean up disused industrial sites.
Before abandoned contaminated industrial sites can be recovered, the distribution and availability of pollutants have to be known in detail.
Motivated by this, Manuel Valiente and Gustavo P?rez from Barcelona analysed an abandoned 40 hectare open-cast mine at Salsigne, France, for various heavy metals.
To do this, the researchers used a sequential extraction scheme (SES). In this process a sequential series of selective extractant reagents, each a more powerful extractant than the last, is employed to selectively dissolve or solubilise the different solid phases or mineralogical fractions of heavy metals. In a new approach, Valiente combined the SES results with chemometric data processing to better determine the pollution trends and distribution of heavy metals in the studied area.
This combined approach bodes well for assessing other contaminated industrial sites. As Valiente comments: ’The value of the information obtained can be appreciated in the risk assessment of such polluted sites, as well as in addressing specific solutions for their appropriate remediation.’