Assessment of Hydrocarbons in Soil along Crude Oil Pipeline Route in Rivers State, Nigeria

The spillage of crude oil from the network of pipelines in the Niger Delta has been a source of concern. As a result, it became necessary to assess the extent of soil contamination along a pipeline route in Rivers State. The concentrations of TPH, PAHs and BTEX in soil along crude oil pipeline route were investigated. The pipelines are located in Idu communities, near Port Harcourt, Rivers State, Nigeria. Sampling of soils was done at two depths (0 – 15 cm and 15 – 30 cm) quarterly (January, April, July and October) at ten (10) stations and one control point, established at 1.5 km from the sampling stations. TPH, PAHs and BTEX in soils were analyzed using the GC-FID and Headspace respectively. The results obtained revealed that the soil was strongly contaminated with TPH and PAHs while BTEX was not detected. The concentrations (mg/kg) of TPH (371.83, 368.34, 353.00, 326.38 and320.84, 349.75, 303.39, 327.93) and PAHs (18.09, 25.94, 17.38, 17.96 and 12.10, 19.35, 12.86, 16.61) obtained in surface and subsurface soils respectively were not significantly different (p>0.05) across the four quarters of the year. However, there was significant difference (p<0.05) across the sampling stations. The degree of hydrocarbons contamination of soil was SS 7 > SS 8 > SS 10 > SS 6 > SS 5 > SS 4 > SS 9 > SS 1 > SS 3 > SS 2. The TPH and PAH concentrations obtained in soil exceeded their respective target values of the DPR in oil spilled soil nevertheless, below their respective intervention limits.