Remedies for soil and groundwater pollution: An overview

Most urban cities are experiencing population growth and increased industrial activities. This has brought most urban soil and groundwater environments under stress. There are reports of soil and groundwater pollution through landfills, gas and oil pipelines, industrial spills and leakages from underground storage tanks (USTs). Pollutants range from heavy metals to volatile organic compounds (VOCs), light non-aqueous phase liquids (LNAPL) (floaters) and dense non-aqueous phase liquids (DNAPL) (sinkers). Remediation methods depend on such factors as type, mobility and extent of contamination, pollutant spread, pedology, physiography, geology and hydrogeology of the area. Furthermore, remediation method would depend on available technology, economic, institutional and environmental laws. Field oriented methods are described with documentations that must accompany them. Finally, this overview concludes with a discussion of the problems of follow-up monitoring and future challenges of remediation methods.