Transporte advectivo de cloretos: estudo de caso

Abstract

Presaming contamination of the Rio da Batateira aquifer through waste water injeted into the Macacos creek in Juazeiro do Norte, we used MODFLOW and MT3D to investigate groundwater flow conditions and the impacts from the creekon groundwater. The creek turned perennial due to coast water domestic and from small industries in the neighourhood. As a tracer for contamination we used chloride. Computational simulations show: (i) depression cones produced through pumping within a well field are more pronouced for wells close to the creek; (ii) groundwater flow velocity is of the order of 10-5 m/s (0,9 m/day) and the highest values occur, due to intense pumping, in the área of the well field; (iii) the plume of contamination advances predominatly vertically due to pumping and induced recharge of the aquifer through the creek; (iv) the high level of aquifer contamination through chloride can be reduced to natural concentrations in a span of abaut one year in the case of stopping the injection of coast water into the Macacos creek.