EDAFOLOGÍA, VOL 15. (1,1 2, 3), PP 33-52 2008


INVESTIGACIÓN Y CONFINAMIENTO DE SUELOS CONTAMINADOS POR HEXACLOROCICLOHEXANO EN EL POLÍGONO DE TORNEIROS –O PORRIÑO- (PONTEVEDRA)

VARELA-CASTEJÓN Calixto; MARTÍNEZ LOZANO Francisco; BLASCO HERGUEDAS, Oscar


Eptisa, Servicios de Ingeniería, S.A. Rúa Pablo Iglesias no2, Bajo. 15174 Vilaboa, Culleredo (A Coruña)


Abstract

In a residential area in O Porriño (Pontevedra, Spain-NO) was detected the presence of an area where waste from the production of lindane was dumped. Between 1998 and 2000, a research on the presence of contamination in soil and groundwater allowed the identification of the most affected areas by various isomers of hexachlorocyclohexane (HCH).
The human health risks analysis conducted indicated the presence of unacceptable levels of risk, so it was necessary an action to interrupt the routes of exposure to pollution. After shuffling diverse alternatives it was concluded that the most appropriate at that time was the placement of the soil in a security cell constructed in situ.
For the definition of the project, diverse numerical models of the behavior of groundwater and contamination were developed as a technical support to decision making about the design of the security cell. The confinement was finally executed by the construction of cement-bentonite panels up to a maximum depth of 30 meters (to embed them into the impermeable substrate) and a multilayer surface sealing composite from surface to depth: topsoil, soil, drainage geocomposite, bentonite geocomposite and geotextile.

Keywords: Lindane, HCH, aquifer, soil contamination, Torneiros, ModFlow, MT3D, security cell, numeric model