Publication Title Application of 2-D Electrical Resistivity Tomography and Modeling for Sand Exploration at Evbarue, Edo State, Nigeria
Publication Type journal
Publisher IOSR Journal of Applied Geology and Geophysics
Paper Link www.iosrjournals.org
Publication Authors Irunkwor, T. C, Eghobamien, L.O and Abanjo, N
Year Published 2022-09-30
Abstract Vertical electrical sounding and 2-D electrical resistivity tomography was applied to investigate the availability of sand and estimate the volume of exploitable sand deposit in a municipality in the Western Niger Delta. Vertical electrical sounding (VES) and 2-D resistivity tomography was investigated using the Petrozenith PZ-03 terrameter with the Schlumberger and Wenner arrays respectively. The VES and 2-D resistivity survey results were respectively interpreted with IPI2WIN and DIPROWIN softwares. Resistivity results delineated 3 layers of lateritic topsoil, sandy clay, and sand. The VES and 2-D tomography mapped and identified sand deposits of varying resistivity values ranging from 1362?m to 4040?m at a depth range of 1.5m to 39.6m. The sand deposit was characterized by medium to coarse grained sand that is moderately sorted. An estimated volume of 867,122m3of sand is available for mining from the 138,912,944 tonnes of sand deposit which is considered sufficient enough to be of economic value. Since mining this volume of sand will have adverse environmental effects on the river micro-ecology and the community, it is advised that conscious steps be taken to minimize ecological and environmental effects, and the river flow be directed away from sensitive and vulnerable banks in order to avoid erosion and bank instability.
Publication Title Electrical Resistivity Investigation for Aquifer Vulnerability to Surface Contaminants at Dumpsites in Western Niger Delta Download PDF
Publication Type journal
Publisher International Journal of Innovative Science and Research Technology
Paper Link www.ijisrt.com
Publication Authors Irunkwor, T. C and Abanjo, N
Year Published 2022-08-08
Abstract Vertical electrical sounding, 2-D resistivity imaging and Dar-zarrouk parameters were used to investigate leachate plume generation, migration and the strength of the overlying protective capacity to prevent contamination of the groundwater aquifer at a municipality in the Western Niger Delta. Twelve vertical electrical sounding was investigated using the Mini-Res Resistivity Meter with the Schlumberger array. Dar-zarrouk parameters were employed to determine the protective capacity of overburden rock and the vulnerability of the aquifer to surface contaminants. The VES result was interpreted with Winglink software and delineated 5 layers of lateritic topsoil, sandy-clay, fine coarse-sand, medium coarse-sand and coarse sand. The VES and 2-D tomography mapped and identified 2 distinct zones of low resistivity values of 91?m and 394?m at depth of 5m to >28m indicating area of leachate contaminant plume;and zone of high resistivity value of 422?m and 5102?m suspected to be dumpsite gases. The Dar-zarrouk parameters showed that the total longitudinal conductance is low ranging from 0.01 Siemens at VES 4 to 0.09 Siemens at VES 6 which is less than the critical value of 1.0 Siemens suggesting that the overburden protective capacity do not have significant clay/shale impermeable beds. The total transverse resistance at each VES station varied from 286.55?m2 (at VES 9) to 4,949.18?m2 (at VES 6) interpreted as layers of high transmissivity indicating that the aquifer materials are porous and permeable to fluids flow. The aquifer overburden protective capacity and vulnerability ratings are respectively poor and extremely high vulnerability. The low values of overburden protective capacity of the sandy-clay layer and the high transmissivities of the vadose zones and the aquifers will aid the seepage and migration of contaminants within and around the dumpsites subsurface layers. Proper hydrogeophysical characteristics of the area should be considered before citing and drilling of boreholes.
Publication Title Assessment of Natural Radionuclides and Radiological Health indices in Soil of Oil Producing Communities, Rivers State, Nigeria Download PDF
Publication Type journal
Publisher International Journal of Advances in Engineering and Management (IJAEM)
Paper Link www.ijaem.net
Publication Authors Irunkwor, T. C, Abanjo, N and Ogboi, K. C
Year Published 2022-09-09
Abstract The natural radionuclides and radiological health indices associated with the use of soil in communities with history of oil spillage, gas flaring, oil bunkering and operation of illegal artisanal oil refining activities in Rivers State was here assessed and measured with gamma ray spectroscopy. The results showed that the mean activity concentration of radionuclides in soil samples ranged from 17.77±4.20Bq/kg to 31.84±3.20Bq/kg for 238U, 22.75±3.30Bq/kg to 33.82±4.70Bq/kg for 232Th and 110.44±9.60Bq/kg to 483.15±18.20Bq/kg for 40K, and are within permissible standard, but are higher than the mean activity in the control. Results further revealed that there was statistically significant difference at p<0.05 in the mean variations of the activity concentrations of natural radionuclides in the soil within the five communities and the control. The radiological hazard indices are all within tolerable values except for Bunu-Tai community whose annual gonadal equivalent dose was about 19.6% or 1.19 times higher than the international permissible value of 300mSv/y. Remediation measure is therefore recommended to minimize the risk of radiation from enhanced natural radionuclides in the soil.
Publication Title Assessment of Natural Radioactivity and Radiological Hazard indices in Cassava Cultivated in Oil Producing Area, Rivers State, Nigeria Download PDF
Publication Type journal
Publisher International Journal of Applied Science and Research
Paper Link https://doi.org/10.56293/IJASR.2022.5444
Publication Authors Irunkwor, T. C, Abanjo, N and Ogboi, K. C
Year Published 2022-09-05
Abstract The natural radioactivity and radiological hazard indices associated with the consumption of cassava crops grown in five communities with history of oil spillage, gas flaring, oil bunkering activities and operation of illegal artisanal oil refining in Rivers State was assessed and measured with gamma ray spectroscopy. Five samples of cassava crop and five samples of soil were collected from the five communities. The results obtained were used to evaluate the soil-to-cassava transfer factor (TF) due to ingestion of cassava crops/staple foods by inhabitants in the area. The mean activity of soil samples ranged from 17.77±4.20Bq/kg to 31.84±3.20Bq/kg for 238U, 22.75±3.30Bq/kg to 33.82±4.70Bq/kg for 232Th and 110.44±9.60Bq/kg to 483.15±18.20Bq/kg for 40K, and is within permissible standard, but is higher than the mean activity in the control. The mean activity of cassava samples ranged from 6.50±1.30Bq/kg to 29.70±6.20Bq/kg for 238U, 5.80±2.20Bq/kg to 16.50±6.80Bq/kg for 232Th and 383.20±28.10Bq/kg to 482.30±35.80Bq/kg for 40K and is found higher than those of the control samples, and the international permissible limits. The study revealed that although some of the radiological hazard indices in the cassava samples were below the allowable standards, the estimated committed annual effective dose and excess lifetime cancer risk due to ingestion of cassava crops/staple foods is respectively over 2.9 times and 5.9 times higher than the international permissible limit of 0.29mSv/y. The rate of radionuclides transferred from soil-to-cassava has mean TF of 232Th < 238U <40K. It is therefore recommended that a community based awareness programme on the issue of environmental contamination from extraneous activities, its health impacts due to consumption of cassava crops/staple foods in the area and possible prevention be organized by the various government agencies involved in environmental protection.
Publication Title 2-D RESISTIVITY IMAGING AND HYDROGEOCHEMICAL ANALYSIS FOR LEACHATE MIGRATION AT DUMPSITES IN SOUTH-SOUTH NIGERIA Download PDF
Publication Type journal
Publisher International Journal of Environmental Sciences
Paper Link www.iprjb.org
Publication Authors Irunkwor, T. C and Abanjo, N
Year Published 2022-09-11
Abstract Vertical electrical sounding, 2-D tomography and hydrogeochemical analysis was applied to investigate dumpsite leachate plume generation, migration and its impact on the surrounding soil and groundwater aquifer at a municipality in the Western Niger Delta. Twelve vertical electrical sounding (VES) was investigated using the Mini-Res Resistivity Meter with the Schlumberger array. The VES survey result was interpreted with Winglink software. Five hand-dug well water and 5 tap/borehole water samples was collected for hydrogeochemical analysis using the sterile plain bottles and 1-litre plastic bottles. Resistivity results delineated 5 layers of lateritic topsoil, sandy clay, fine coarse-sand, medium coarse-sand and coarse sand. The VES and 2-D tomography mapped and identified 2 distinct zones viz:zone of low resistivity of 91?m and 394?m at depth of 5m to >28m indicating area of leachate contaminant plume and zone of high resistivity value of 422?m and 5102?m suspected to be dumpsite gases such as NH3, CH4, SO2 and CO2. The 2-D resistivity imaging also revealed that the generated dumpsite leachate contaminant plume was migrating from the Northern part of the burrow-pit dumpsite towards its Eastern part and to the Northern part of the dumpsite at Scot road/Sakponba road. Hydrogeochemical parameter results showed that colour, pH, iron, Lead and coliform bacteria exceeded permissible standard indicating that the leachate plume has migrated to the groundwater aquifer. Closed municipal landfill whose base is made of concrete and paved surfaces should be adopted in the area to prevent leaching of poisonous substances into groundwater aquifer.
Publication Title Determination of Elemental Concentration of Natural Radionuclide in Soils of Industrial Communities, South- South Nigeria Download PDF
Publication Type journal
Publisher United International Journal for Research & Technology
Paper Link UIJRT.COM.
Publication Authors Irunkwor T. C. and Abanjo N.
Year Published 2022-09-13
Abstract The elemental concentration of natural radionuclides in soil of some communities in South-South Nigeria with history of oil spillage, gas flaring, oil bunkering and operation of illegal artisanal oil refining activities was determined and measured with gamma ray spectroscopy. The activity concentration values of radionuclides in soil were converted to elemental concentration values. The result showed that the mean value of elemental concentrations in the soil samples ranged from 1.44±0.34 to 2.58±0.26ppm for uranium, 5.60±0.81 to 8.33±1.16ppm for thorium and 0.35±0.03 to 1.54±0.06% for potassium. These mean elemental concentration values are respectively lower than the worldwide standard of 2.7ppm, 11ppm and 1.3ppm in the soil of the five sampled communities except for the potassium value in the soil at Bunu-Tai that was higher than the permissible standard by 0.24%. The Th/U elemental ratio in the soil samples at Eleme and Bunu-Tai communities are respectively 4.68 and 4.84 and are over 1.6 times higher than the theoretical standard value of 3.0 for normal continental crust indicating an enrichment of thorium and depletion of uranium radionuclides in these communities. The Th/U elemental ratio in the soil samples at Ban-Ogoi, Bodo and Giokoo communities are respectively over 1.4 times lower than the 3.0 standard for normal continental crust showing a depletion of thorium and enrichment of uranium in those communities. Relative depletion/enrichment of natural radionuclides occurred in soils of the sampled communities arising from alteration of natural processes by anthropogenic/metamorphic activities.