A least squares method for identification of unknown groundwater pollution source

Abstract

The identification of unknown groundwater pollution sources is one of the most important premises in groundwater pollution prevention and remediation. In this paper, an exploratory application of a least squares method to identify the unknown groundwater pollution source is conducted. Supported by a small amount of observation data and the analytical solutions of the pollutant transport model, the initial concentration, the leakage location and the pollutant mass are identified by using the least squares method under a sand tank experiment and a gas station area. In the sand tank experiment, it is found that the fitting errors of three cross-sections are within 6%. In the gas station area, it is found that the results are nearly consistent with the site investigation information. The results indicate that the least squares method has considerable application values in the identification of groundwater pollution sources. HIGHLIGHTS A least squares method is conducted in a sand tank experiment and a gas station area.; The initial concentration, the leakage location and the pollutant mass are identified.; The relative errors between observed values and fitting values are within 6%.; Provide a new approach to identify unknown groundwater pollution sources.; The release history of the tank is speculated.;

Keywords

• groundwater
• identification
• least squares method
• multivariate nonlinear regression
• pollution source