The Effect of Nutrients, Compost, and Local Bacteria in Bioremediation of Petroleum Contaminated Soil

Abstract

Petroleum hydrocarbon contamination in soil can be overcome by chemical, physical, and biological techniques. Biological  approach to cope with petroleum hydrocarbon pollution is known as bioremediation. Bioremediation research using laboratory scale land-farming technique has been carried out. The initial activity of this bioremediation study was enrichment and bacterial multiplication of indigenous bacteria in polluted area as a mixed bacterial consortium. Treatments were performed on 3 level of total petroleum hydrocarbon (TPH) at about 5, 8, and 11%, in original contaminated soil as well as biostimulation by the addition of nutrients, compost, and bioaugmentation by enriched microbes within 19 weeks. From week 4 to 19,  pH of soil in the reactors was between 5.0 to 8.5 with soil temperature between 30.0-40.5°C. The moisture content fluctuated from 4.86% to 47.21%. The population of microbes performed weekly from log 8.70 to 23.76 CFU/g-dried-soil. The production of CO2 gas fluctuated, the highest CO2 production value achieved from C1 treatment (nutrients and compost at TPH 5%) compared with other treatments. The TPH degradation depended on treatment of initial TPH, nutrient, and compost.The largest percentage of TPH degradation were  obtained from the treatment of  N3 (nutrients and TPH 11%) at 52.1%. Bioaugmentation using local microbes did not affect on TPH degradation. Therefore, bioaugmentation was not needed if compost has been added. Keywords:bacteria, bioremediation, compost, contaminated soil, nutients, petroleum hydrocarbon