STM Article Repository

Studies to investigate the potential of leaf litter and hydrogen peroxide to remediate a crude oil polluted soil were carried at the Research farm in Rivers State University Port Harcourt. The experiment had 14 treatments and 5 replicates. The treatments were as shown :T1:100 ml Crude Oil (C/O) + 100 ml Hydrogen peroxide (H2O2), T2:100 ml C/O + 100 g Leaf litter (l/l), T3:200 ml C/O + 200 ml H2O2, T4:200 ml C/O + 200 g l/l, T5:300 ml C/O + 300 ml H2O2, T6:300 ml C/O + 300 g l/l, T7:400 ml C/O +400 ml H2O2, T8:400 ml C/O + 400 g l/l, T9:500 ml C/O + 500 ml H2O2, T10:500 ml C/O + 500 g l/l, T11:no pollution + 500 ml H2O2, T12:no pollution + 500 g l/l, T13:500 ml C/O + no amendment and T14: (no pollution+no amendment) as control. Soil samples were analysed to ascertain the physico-chemical properties before pollution, after pollution and after remediation. The experiment lasted for 4 months. Results of physico-chemical parameters reduced to acceptable limits after amendment with both H2O2 and leaf litter in the soils. Phosphate content had irregular increases in all the treatments but T1, T2, T11 and T12 had the highest values of phosphate content (8.0-8.5) in the 1st, 2nd and 3rd month after remediation, while there was a decrease in phosphorus content after 4months of remediation. Total organic carbon increased on all the treatments in accordance with the levels of crude oil pollution. The highest Total Organic Carbon (TOC) values were seen in T9, T10 and T13 (51.1 – 53.4) while the least TOC values were recorded in unpolluted and remediated soils and the control with values within the ranges of (9.2 – 11.0). Crude oil adversely affected the potassium content which gradually increased with time. There was a great reduction in TOC content after 4 months of remediation with values within the ranges of (22-23). Phosphorus content had irregular increases in all the treatments up till the 3rd month after amendment and decreased at the 4th month of remediation. This implied that the remediating agents reduced the excess phosphorus content in the soil.