Contamination by NOx type Pollutants in the Leach Ate from the Andralanitra Garbage Dump (Antananarivo Madagascar)

The study concerns the analysis of physic-chemical parameters in order to establish the state of pollution of a garbage dump site. The interpretation of the data is done by standardized principal component analysis. Thus, leachate samples were taken at 9 study stations in wet and dry periods. The results show that among the parameters studied, there is a high content of BOD5 (592,035 mg/L), EC (16,786 mS/cm) and COD (1373,684 mg/L). The concentration level of nitrates and nitrites greatly exceeds the norm; for the old landfill, the NO2- contents vary from 191,527 mg/L to 875,206 mg/L and the NO3- ranging from 384,926 mg/L to 1584,021 mg/L, we thus observe the influence of humidity on the concentrations of physic-chemical parameters. Furthermore, the chemical composition and mass concentrations of pollutants at the sites are highly dependent on the nature of the waste and the degree of pollution differs from one site to another. The considerable increase in the content of these pollutants is favored by bacterial activities during the transformation of the organic matter present in the leachate. However, the importance of the degree of contamination of the landfill favoring the pollution of the receiving environment is confirmed.