Historic analysis of heavy metals' concentration in reprocessed amalgamation tailings in Mexico

ENVR 176

Irma G. Gavilan1, Elvira S. Santos, elvirass@servidor.unam.mx1, Arturo Gavilán-García, agavilan@ine.gob.mx2, Mario Yarto, myarto@ine.gob.mx2, R. Rosiles, rosiles@servidor.unam.mx3, Sara T. Suarez1, and Jesus Olmos Sr.1. (1) Environmental Division, Chemistry School, UNAM, Ciudad Universitaria 04510, Coyoacan, Mexico, (2) Dirección de Investigación sobre Sustancias Químicas y Riesgos Ecotoxicológicos, Instituto Nacional de Ecología, Periférico Sur 5000, Col. Insurgentes Cuicuilco, Delegación Coyoacán, Mexico, D.F, 04530, Mexico, (3) Lab. de Toxicología, Fac. de Medicina Veterinaria y Zootecnia, UNAM, Ciudad Universitaria, México D.F, 04510, Mexico
Since 1920, small tailing reprocessing companies have lixiviated tailings using a diluted solution of CaS2O3 to extract precious metals from ancient tailings in Zacatecas, Mexico. This empiric process has low extraction efficiency, having an important residual heavy metals' concentration in the reprocessed tailings. There is no scientific evidence regarding the risk to health or environment of the available species of the metals left in the reprocessed tailings and their dispersion routes. The main goal of this study is to establish the heavy metal concentration profile in a reprocessed tailings disposal site where tailings have been stored since 11 years ago and, from this, identify the mobility of pollutants to other environmental compartments. This study consisted in the analysis of the concentration of arsenic, mercury, lead and silver in 34 soil samples by atomic absorption spectrometry. With this, the distribution of contaminants was identified and the dispersion pattern calculated.
 

General Papers
6:00 PM-8:00 PM, Wednesday, 13 September 2006 Moscone Center -- Hall D, Poster

Division of Environmental Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006