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.

识别未知的地下水污染源是预防和修复地下水污染的最重要前提之一。本文在最小二乘方法的探索性应用中，对未知的地下水污染源进行了识别。在少量观测数据和污染物迁移模型的解析解的支持下，采用最小二乘法在沙罐实验和加油站区域内确定初始浓度，泄漏位置和污染物质量。在砂罐实验中，发现三个横截面的拟合误差在6％以内。在加油站区域，发现结果与现场调查信息几乎一致。