Hydrocarbon contamination from oil spills presents geoenvironmental and geoengineering challenges,notably in Eleme,Nigeria.This study integrates electrical resistivity tomography(ERT),soil total petroleum hydrocarbon(...Hydrocarbon contamination from oil spills presents geoenvironmental and geoengineering challenges,notably in Eleme,Nigeria.This study integrates electrical resistivity tomography(ERT),soil total petroleum hydrocarbon(TPH)analysis,and geotechnical testing for treated spill site monitoring and characterization over six months.Four 100 m ERT lines,L1 to L4,with spacings at 1.5 m,3 m,6 m,9 m,12 m,and 15 m,were established for the first and second sampling phases.Twenty-one soil samples,12 TPH,and 9 mechanical analyses,were obtained from 5 boreholes,BH1 to BH4,for the study site and the BH5 control site across the phases at 0.5 m,3.0 m,and 5.0 m depths along ERT lines.ERT results reveal resistivity reductions averaging 18%in shallow zones of active degradation,correlating with an average 41%TPH-decrease.Specific gravity averaged 2.49 in the spill soils,compared to 2.58 in control samples,reflecting hydrocarbon-induced density reductions of 3.5%.Particle size showed spill soils contained>50%fines,increasing water retention and reducing permeability by 30%.Consolidation tests highlighted increased compressibility,with settlements of 1.89 mm in spill soils versus 1.01 mm in control samples,indicating a 47%increase in settlement from hydrocarbon reduction.Correlation analysis shows slower consolidation at BH3(−0.62 Cv)with moderate settlement increase(0.25),while BH4 exhibits much higher compressibility(0.95)but minimal Cv impact(0.23),indicating increased structural weakness with higher residual TPH.Spill degradation reduced TPH by 19%-64%in shallow zones,with persistent contamination at deeper layers exceeding the regulatory limits,emphasising the need for ongoing monitoring and targeted remediation for long-term stability and sustainability.展开更多
The Niger Delta region of Nigeria is heavily impacted by petroleum explora-tion,refining activities,and industrial emissions,contributing to widespread aerial petro-pollutant contamination.This study investigates the ...The Niger Delta region of Nigeria is heavily impacted by petroleum explora-tion,refining activities,and industrial emissions,contributing to widespread aerial petro-pollutant contamination.This study investigates the hydrochemi-cal dispersion and geospatial correlation of atmospheric petroleum hydrocar-bons(TPH)deposited through rainfall within selected locations in Rivers State,Nigeria.Thirty-four rainwater samples were collected from seven distinct sub-regional study locations:Obigbo,Komkom,Obiama,Okoloma,Egberu,Umu Agbai,and Obete.Hydrochemical analyses were conducted using gas chroma-tography-flame ionization detection(GC-FID)to quantify total petroleum hy-drocarbons(TPH),with detailed compositional profiling of aliphatic hydro-carbons(C8-C40)and polycyclic aromatic hydrocarbons(PAHs).The disper-sion analysis employed Hexbin density mapping,Contour visualization,and spatial interpolation techniques to delineate pollution hotspots,revealing sig-nificant contamination gradients across the study region.The correlation ma-trix assessed interrelationships between hydrocarbon fractions and geographic positioning,identifying strong positive correlations(r>0.9)between TPH and total aliphatic hydrocarbons(TAH),suggesting transportation and industrial emissions as primary sources.PAHs exhibited localized concentration spikes,particularly near gas flaring zones and commercial hubs,implicating fossil fuel combustion,industrial activities,and long-range pollutant transport as domi-nant contamination mechanisms.Geospatial analysis indicates higher hydro-carbon deposition in the Western and Northern regions,with Obigbo and Okoloma experiencing the most significant contamination.The study high-lights rainfall as a key vector for atmospheric petrochemical deposition,with implications for water quality,ecosystem health,and human exposure risks.These findings emphasize the need for stricter environmental monitoring,reg-ulatory enforcement of industrial emissions,and strategic efforts to mitigate hydrocarbon pollution in petroleum-producing regions.展开更多
基金funded by the Petroleum Technology Development Fund(PTDF),Nigeria.(Award No.:PTDF/ED/OSS/PHD/NOA/1714/20).
文摘Hydrocarbon contamination from oil spills presents geoenvironmental and geoengineering challenges,notably in Eleme,Nigeria.This study integrates electrical resistivity tomography(ERT),soil total petroleum hydrocarbon(TPH)analysis,and geotechnical testing for treated spill site monitoring and characterization over six months.Four 100 m ERT lines,L1 to L4,with spacings at 1.5 m,3 m,6 m,9 m,12 m,and 15 m,were established for the first and second sampling phases.Twenty-one soil samples,12 TPH,and 9 mechanical analyses,were obtained from 5 boreholes,BH1 to BH4,for the study site and the BH5 control site across the phases at 0.5 m,3.0 m,and 5.0 m depths along ERT lines.ERT results reveal resistivity reductions averaging 18%in shallow zones of active degradation,correlating with an average 41%TPH-decrease.Specific gravity averaged 2.49 in the spill soils,compared to 2.58 in control samples,reflecting hydrocarbon-induced density reductions of 3.5%.Particle size showed spill soils contained>50%fines,increasing water retention and reducing permeability by 30%.Consolidation tests highlighted increased compressibility,with settlements of 1.89 mm in spill soils versus 1.01 mm in control samples,indicating a 47%increase in settlement from hydrocarbon reduction.Correlation analysis shows slower consolidation at BH3(−0.62 Cv)with moderate settlement increase(0.25),while BH4 exhibits much higher compressibility(0.95)but minimal Cv impact(0.23),indicating increased structural weakness with higher residual TPH.Spill degradation reduced TPH by 19%-64%in shallow zones,with persistent contamination at deeper layers exceeding the regulatory limits,emphasising the need for ongoing monitoring and targeted remediation for long-term stability and sustainability.
文摘The Niger Delta region of Nigeria is heavily impacted by petroleum explora-tion,refining activities,and industrial emissions,contributing to widespread aerial petro-pollutant contamination.This study investigates the hydrochemi-cal dispersion and geospatial correlation of atmospheric petroleum hydrocar-bons(TPH)deposited through rainfall within selected locations in Rivers State,Nigeria.Thirty-four rainwater samples were collected from seven distinct sub-regional study locations:Obigbo,Komkom,Obiama,Okoloma,Egberu,Umu Agbai,and Obete.Hydrochemical analyses were conducted using gas chroma-tography-flame ionization detection(GC-FID)to quantify total petroleum hy-drocarbons(TPH),with detailed compositional profiling of aliphatic hydro-carbons(C8-C40)and polycyclic aromatic hydrocarbons(PAHs).The disper-sion analysis employed Hexbin density mapping,Contour visualization,and spatial interpolation techniques to delineate pollution hotspots,revealing sig-nificant contamination gradients across the study region.The correlation ma-trix assessed interrelationships between hydrocarbon fractions and geographic positioning,identifying strong positive correlations(r>0.9)between TPH and total aliphatic hydrocarbons(TAH),suggesting transportation and industrial emissions as primary sources.PAHs exhibited localized concentration spikes,particularly near gas flaring zones and commercial hubs,implicating fossil fuel combustion,industrial activities,and long-range pollutant transport as domi-nant contamination mechanisms.Geospatial analysis indicates higher hydro-carbon deposition in the Western and Northern regions,with Obigbo and Okoloma experiencing the most significant contamination.The study high-lights rainfall as a key vector for atmospheric petrochemical deposition,with implications for water quality,ecosystem health,and human exposure risks.These findings emphasize the need for stricter environmental monitoring,reg-ulatory enforcement of industrial emissions,and strategic efforts to mitigate hydrocarbon pollution in petroleum-producing regions.
