ENVIRONMENTAL MONITORING OF THE NORTH PORTO-ALEGRE LANDFILL, BRAZIL

In 1990, the administration of Porto Alegre, Brazil, declared a state of public emergency because its large landfills were not fit for opera tion. Almost 1 000 t/d of domestic, industrial, and hospital wastes we re being sent to the Porto Alegre landfill. Potential hazards to the l ocal water resources have resulted because the landfill, besides recei ving these wastes indiscriminately, was nor equipped with a drainage o r leachate treatment system. In addition, the waste disposal was not c onducted orderly, thus rendering monitoring of the area practically un feasible. Because of the difficulties in finding new suitable sites fo r waste disposal, the city administration opted to recover its northen landfill using an accelerated solid waste stabilization technique. Th is work assesses the results from the monitoring during the first 3 ye ars of implementation of this technique. Chemical oxygen demand (COD), biochemical oxygen demand (BOD5), dissolved oxygen (DO), pH, nitrogen ous series, phosphate, conductivity, alkalinity, total residue, and he avy metals (Al, Ag, Ba, Cd, Cu, Cr, Fe, Hg, Mn, Ni, Pb, and Zn) were d etermined in the surface water, groundwater, and leachate. Biogas samp les taken directly from the flares installed in the various cells were analyzed for CH4, CO2, CO, H-2, O-2, and N-2.