Site characterisation of LNAPL-contaminated fractured-rock aquifer
| dc.contributor.advisor | Van Tonder, G. J. | |
| dc.contributor.advisor | Steyl, G. | |
| dc.contributor.author | Gomo, Modreck | |
| dc.date.accessioned | 2018-03-15T10:04:50Z | |
| dc.date.available | 2018-03-15T10:04:50Z | |
| dc.date.issued | 2009-08 | |
| dc.description.abstract | English: Site characterisation aims to obtain fundamental data needed to describe the subsurface flow pathways and distribution of contaminants. The study describes the application of various geohydrological techniques as complimentary tools to characterise an LNAPL contaminated fractured - rock aquifer on the Beaufort West study area in South Africa. Field investigations were designed to define and determine the properties of the fracture preferential flow paths responsible for LNAPL transportation in a typical Karoo fractured - rock aquifer system. The research places emphasis on the integration of results to maximise the subsurface geological understanding in particular location of fracture features chiefly responsible for facilitating LNAPL migration and distribution. The core and percussion drilling explorations, cross - correlated with borehole geophysics, were valuable for geological subsurface investigations in particular locations of bedding fractures, which are often associated with high hydraulic conductive flow zones. Tracer and pump tests were conducted to determine hydraulic and mass transport parameters respectively. Hydraulically conductive bedding plane fracture flow zones were identified by integrating results from the geological core logs, borehole geophysics and aquifer tests. The chemical characterisation of the study area was conducted by means of organic hydrocarbon, inorganic water analyses and volatile organic carbon measurements in the soil during air percussion drilling. Based on the findings, the hydrogeological structure of the formation was conceptualised as a fractured sandstone aquifer, characterised by bedding plane fracture preferential flow paths at contact areas, with shale and mudstone formations. The study findings demonstrate the merit and value in the application of various geohydrological tools to complement one another for optimised site understanding. The findings and recommendations of the case study are not necessarily confined to LNAPL contaminated fractured - rock aquifers, but may also be applicable to other types of contaminants in fractured - rock aquifer formations. | en_ZA |
| dc.description.abstract | Afrikaans: Die doel van terrein karakterisering is om fundamentele data te verkry wat benodig word om die ondergrondse vloeirigtings en verspreiding van kontaminasie te beskryf. Die studie beskryf die toepassing van verskeie geohidrologiese tegnieke as komplimenterende middele vir die karakterisering van 'n LNWV (ligte nie-wateroplosbare vloeistowwe) besoedelde fraktuur-klip akwifeer in die Beaufort-Wes studie area in Suid-Afrika. Veldondersoeke is ontwerp om die eienskappe van fraktuur voorkeur vloeirigtings te definieer en bepaal. Hierdie vloeirigtings is verantwoordelik vir LNWV vervoer in 'n tipiese Karoo fraktuur-klip akwifeer stelsel. Die ondersoek plaas klem op die integrasie van resultate om die begrip van ondergrondse geologie te maksimeer, veral in terme van die ligging van frakture wat verantwoordelik is vir LNWV migrase en verspreiding. Die kern- en slagboorgat ondersoeke is gebruik en 'n kruis-vergelykking was gemaak met boorgat geofisika. Dit was waardevol in terme van ondergrondse geologiese ondersoeke, spesifiek met betrekking tot die ligging van stratifikasie frakture, wat dikwels geassossieer word met hoë hidroliese en massavervoer parameters. Hidrolies geleidende stratifikasie vlak fraktuur vloei sones is geidentifiseer deur die integrasie van resultate vanaf die kernaantekeninge, geofisiese en akwifeer toetse. Die chemiese karakterisering van die studieterrein is voltooi deur middel van organiese hidrokoolstof, anorganiese water analiese en deur die meting van vlugtige organiese koolstof in die grond gedurende lug slagboorwerk. Die bevindinge dui aan dat die hidrogeologiese struktuur van die formasie as 'n fraktuur sandsteen akwifeer gekonseptualiseer is. Dit word gekenmerk deur stratifikasie vlak fraktuur voorkeur vloeiroetes in kontakareas, met leiklip en modderklip formasies. Hiermee word die meriete en waarde van die bevindinge gedemonstreer in terme van die toepassing van verskeie geohidrologiese middels vir optimale terrein bepaling. Die bevindinge en aanbevelings van die studie is nie noodwendig beperk tot LNWV besoedelde fraktuur-klip akwifere nie; dit kan ook toepaslik gemaak word op ander tipes kontaminasie in fraktuur-klip akwifeer formasies. | af |
| dc.description.sponsorship | Water Research Commission (WRC) | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11660/8041 | |
| dc.language.iso | en | en_ZA |
| dc.publisher | University of the Free State | en_ZA |
| dc.rights.holder | University of the Free State | en_ZA |
| dc.subject | Bedding plane fracture | en_ZA |
| dc.subject | Borehole geophysical characterisation | en_ZA |
| dc.subject | Chemical characterisation | en_ZA |
| dc.subject | Contaminated site characterisation | en_ZA |
| dc.subject | Geohydrological tools | en_ZA |
| dc.subject | Hydraulic characterisation | en_ZA |
| dc.subject | Karoo fractured rock aquifer | en_ZA |
| dc.subject | Light - Non Aqueous Phase Liquids (LNAPLs) | en_ZA |
| dc.subject | Preferential flow path | en_ZA |
| dc.subject | Groundwater -- Pollution | en_ZA |
| dc.subject | Aquifers -- South Africa -- Western Cape | en_ZA |
| dc.subject | Hazardous waste site remediation -- South Africa -- Western Cape | en_ZA |
| dc.subject | Nonaqueous phase liquids | en_ZA |
| dc.subject | Enviromental geochemistry | en_ZA |
| dc.subject | Dissertation (M.Sc. (Institute for Groundwater Studies))--University of the Free State, 2009 | en_ZA |
| dc.title | Site characterisation of LNAPL-contaminated fractured-rock aquifer | en_ZA |
| dc.type | Dissertation | en_ZA |