Quick Assessment of Contamination Threat to Groundwater after NAPL Spill

Environmental accidents occur frequently in China in recent years. A quick estimation of the extent and distribution of contamination after environmental accidents is important for immediate treatment of the contaminated sites. This paper proposed a methodology to estimate the velocity and maximum infiltration depth of NAPL after spill accidents to provide quick and quantitative information for the emergency treatment of the site. The proposed methodology uses only the basic information of the accident: contaminant type and its properties, groundwater level, soil type and average properties, and estimated infiltration area. By comparing the maximum infiltration depth of NAPL with the depth to groundwater, one can identify whether there is an immediate threat to groundwater. If there is such a danger, proper measures should be taken within the suggested time frame to prevent NAPL from entering the saturated zone.