Eng. Alfredo Carlos Cardoso Rocca, Master on Hydraulic and Sanitation Engineering by Politechnical Scholl of Engineering of São Paulo University, Manager of the Contaminated Sites Division - ESC of the Environmental Protection Agency of São Paulo State – CETESB, Av. Professor Frederico Hermann Jr. 345, CEP 05459-900, São Paulo (SP), Brazil, Email: alfredor@cetesb.sp.gov.br.

São Paulo State is the most developed and industrialized of Brazilian States, corresponding to almost 40% of internal gross production and more than 30% of exportations of the country. Due to its development, mainly before 1970, when environmental care and sustainability were not a concern, some sites have been contaminated by improper storage, manipulation and disposal of chemicals. These contaminations affected the air, soil, waters, sediments and vegetation.

CETESB, the environmental protection agency of São Paulo, have been taking care of contaminated sites since 1980, when the first cases have been discovered, due its environmental control actions. More recently, with the increment in the number of contaminated sites and the evidence of exposed people, the company have intensified and improved its performance in the management of contaminated sites.

Up to December of 2004, it has been detected 1336 contaminated sites in São Paulo State: 931 (69%) due to fuel storage; 237 (18%) to industrial activity; 92 (7%) to commercial activity; 61 (5%) to waste disposal and 15 (1%) to contingence. The main contaminants are: petrolleum fuels; aromatic solvents, metals, halogenated solvents and PAHs.

To manage contaminated sites, CETESB has developed the following tools: establishment of orientation values for soil and groundwater; announcement of management procedures to be followed by all stakeholders; publishing of a technical manual for contaminated sites management.

The management of contaminated sites is based on a sequence of activities that includes: preliminary evaluation of sites were it has been developed activities that may pollute soil and groundwater; confirmatory investigation of the sites suspected of contamination; detailed investigation and risk assessment of the contaminated sites; definition and project of remediation; execution of remediation, closure and monitoring.

At present, the sites are in the following stages of management:  710 (54%) - detailed investigations in course; 123 (9%) - remedial technology defined; 484 (36%) - remedial actions in course and 19 (1%) - remediation works concluded.

Regarding the remedial technologies that are being applied in the sites were remedial actions are taking place we have: Pump and Treat (271 sites); Free phase recovery (205 sites); soil vapor extraction (171 sites); soil/waste removal (124 sites); hydraulic barrier (35 sites); biorremediation (24 sites); monitored natural attenuation (23 sites); chemical oxidation (6 sites).

Efforts are being made in the state to approve a specific law for contaminated sites and to create a financial fun to support remediation action in the sites.

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