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LONG TERM ASSESSMENT AND CHARACTERISATION OF HYDROCARBON CONTAMINATED SITE IN BARUWA, LAGOS STATE.UDUEBOR MICHEAL A.CVE/06/7988FEBRUARY, 2015Supervisor: prof. s.a. ola1My name is UDUEBOR MICHEAL A. with matric number CVE/06/7988.I am here to present my propositional seminar on the research topic LONG TERM ASSESSMENT AND CHARACTERISATION OF HYDROCARBON CONTAMINATED SITE IN BARUWA, LAGOS STATE..1INTRODUCTIONHYDROCARBON CONTAMINATION2INTRODUCTIONSince the inception of the discovery of crude oil and its derivatives, hydrocarbon contamination originating from the activities of man have entered the subsurface environment through spillage, land application and waste disposal practices, either on purpose or by accident.3We are all fully aware of hydrocarbon contamination into the subsurface either through to spillage, land application and waste disposal practices which occur either on purpose or by accident.3INTRODUCTIONThe presence and transport of these contaminants constitute a potential threat to human health and ecosystems hence, protection of public health and ecosystems rely on the ability to predict the transport and distribution of contaminants in the vadose and saturated zones (van de Weerd, 2000).

4These contaminants constitute a potential threat to human health4AIM AND OBJECTIVESRESEARCH FOCUS5AIM AND OBJECTIVESThe aim of the study is to characterize the Light Non Aqueous Phase Liquids (LNAPL) contamination through the use of existing geohydrological field techniques within the area with a view to accessing the current level of contamination within the area in comparison with previous ground data obtained from the study site in 2006 and determine the degree of remediation by natural attenuation that has taken place between 2006 and 2014.

66AIM AND OBJECTIVES The specific objectives include:Hydrological characterization of the site and free hydrocarbon product levels characterization of selected wells within the area.Determination and correlation of stratigraphy for the study site using field geotechnical investigation with a view to understanding the effect of the stratigraphy on the flow of the contaminant.

77AIM AND OBJECTIVESDetermination of the current pathway of contaminant migration within the subsurface of the study area.Determine natural attenuation levels of hydrocarbon within the area, using previous data obtained

88JUSTIFICATIONWhy This Research?99JUSTIFICATIONAdequate and continuous monitoring of hydrocarbon contaminated sites proves to be the essential key to understanding the behavior of the contaminant once within the subsurface. Any remediation efforts to be carried out within the area would rest heavily on the results gotten from monitoring.1010JUSTIFICATIONThe need for a detailed characterisation on LNAPL contaminated sites, with the objective of providing valuable information prior to remediation exercises and improvement of knowledge is the core motivation for this study.The study would serve as a knowledge base for remediative action within the area and also provide scientific data for the site.

1111SCOPE OF THIS STUDYThe Extent of This Research12SCOPE OF THIS STUDYThe scope of this study would involve the assessment of the current levels of contamination within the area and comparison of data gotten with that of previous assessments carried out by Adekunte (2007) and Balogun (2008). It would cover locations previously utilized by both and also include newer locations to further improve the characterization of the site.

1313LOCATION OF THE STUDY AREALocation of the Research14LOCATION OF THE STUDY AREAThe Baruwa area is located in Ipaja, between the popular Iyana-Ipaja Bus-stop and the Ikotun Area of Alimosho Local Government Council of Lagos State, South West Nigeria. It is about 2.5km from Iyana-Ipaja Bus Terminal and is bounded by Gowon Estate and Abesan Estate to the right and left respectively while coming from Iyana-Ipaja Bus Terminal.1515Map of Lagos, outset showing the location of Baruwa.

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17EXPECTED CONTRIBUTION TO KNOWLEDGEAddition to Knowledge18EXPECTED CONTRIBUTION TO KNOWLEDGE This study is expected to:broaden the knowledge base as regards site characterization and monitoring within the study location this is essential for any meaningful assessment leading to remediative action within the area.provide sufficient data for analyzing the contamination plume, migration and subsoil mass affected.

1919EXPECTED CONTRIBUTION TO KNOWLEDGEvalidate in-situ natural attenuation within the area as hypothesized by Ojuri (2009). 2020MATERIALS AND METHODOLOGYResearch Process21MATERIALS The study would employ collection of field data from the contaminated site in Baruwa, Lagos employing equipment and methods to sufficiently characterize the hydrocarbon contamination within the area.

22MATERIALSGlobal Positioning System (GPS) A GPS device, etrex Garmin II plus would be used to determine the position of observed wells within the area globally. This data is necessary for proper location and identification of the wells.

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MATERIALSOil/Water Interface Meter The Oil/Water Interface meter would be employed to the measure thickness of free hydrocarbon on groundwater in water supply wells. The Solinst Oil/Water Interface Meter gives clear and accurate measurements of product level and thickness in the wells

24MATERIALSPortable Hydrocarbon Analyzer (PHA) The PHA-100 portable hydrocarbon analyser would be used to measure ppm levels of TPH in vapour or water in the field and in real time (in-situ).

25METHODOLOGY Characterization of the study area would be conducted utilizing the following adjusted methodology as prescribed by United States Environmental Protection Agency (US EPA) (2001).

A brief summary of the work to be carried out is given below each heading.

26METHODOLOGYDesktop StudyA review of the site contaminant history would be conducted; this includes potential LNAPL sources at the site and the affected receptors. Historical groundwater levels and quality would be obtained from previous studies within the area (Adekunte (2007), Balogun (2008)) as part of the local geohydrological review. 2727METHODOLOGYSite Survey (Walkover and Visual inspection)This would be conducted to verify the validity of the information collected during the desktop study. Emphasis would placed on fixing the exact positions of the wells (utilizing a GPS tracker), linking previous test carried out on the existing wells within the area.

2828METHODOLOGYHydrological (Water Table) and Free LNAPL Product CharacterizationA water table characterization exercise would be conducted as an extension of earlier studies to determine the number of wells that are still available for testing within the area and their characteristic depth to liquid and to bottom. Also free LNAPL thicknesses would be measured within the wells

2929METHODOLOGYChemical CharacterizationChemical analyses would be conducted for the study area. Dissolved hydrocarbon compound analysis (TPH, BTEX and Contaminant Equivalent) would carried out using the PHA-100 Hydrocarbon Analyzer. Contamination levels would also be measured in vapor within the wells

3030METHODOLOGYSite Conceptual Contamination ModellingA conceptual model would be developed utilizing data collated from desk study and field work. Models would be processed utilizing softwares not limited to Google Earth (pro), ArcGIS., Surfer, MODFLOW, GeoStudio and SV Office, all Geospatial, Geotechnical and Hydrogeological engineering softwares to sufficiently characterize the contamination within the area.

3131PROJECT SCHEDULERESEARCH DURATION32Sequence of WorkSequence of WorkDuration (Weeks)Desk Study, Field Testing Plan Mapping3Field Tests, Analysis of Results10Collation, Correlations, Discussions, Report Writing8Thesis Report, Final Seminar5Total1633Sequence of WorkWeeks12345678910111213141516Desk Study, Field Testing Plan MappingField Tests, Analysis of ResultsCollation, Correlations, Discussions, Report WritingThesis Report, Final Seminar34THANK YOU FOR LISTENING35