Sustainability Report 2004

Environmental aspects

Industrial operations | Monitoring of effluents

Since 1978, Aracruz has been conducting environmental studies in the ocean adjacent to the underwater outfall from the Barra do Riacho Unit. The outfall consists of two pipes that release the effluent at a water depth of 17 m, as well as diffusers on their outlets that dilute the effluents to a level of 1/100.

Over the years, the monitoring program has been adapted to include feedback from data and the new configurations assumed by the industrial complex.

As of 1994, more detailed studies have demonstrated there is no consistent evidence that the release of Aracruz’s effluents has caused cumulative damage to or significant change of the marine ecosystem, even taking into account the increase in production by the Barra do Riacho Unit.

The Guaíba Unit monitors the impact of effluent discharge at three points of Guaíba Lake: upstream, at the point of discharge, and downstream. The effects of chronic toxicity and genotoxicity are evaluated at these points in terms of both surface water and sediments. The outfall discharges effluent into the lake’s navigation channel where outflow is highest, providing a faster rate of diffusion. Quarterly checks are also performed of reproductive conditions and abnormalities in fish collected from various points of Guaíba Lake. The results of physical-chemical monitoring and evaluations of toxicity and abnormalities in fish show no significant impact over the years. A reduction of around 20% in the generation of effluents was obtained during 2004 as a result of recycling water within the production process.