深井水为深层地下水，即第一层不透层以下的地下水。深井水现已成为人类的主要饮用水源。在美国５０％的人口和农村人口的９０％饮用地下水［１］，我国城市１／３的水源亦是深井水，以深井地下水为水源的简易集中供水已成为我国农村改水的主要形式。据１９９３年全国农村饮用 Deep well water is deep groundwater, which is groundwater below the first permeable layer. Deep well water has now become the main source of human drinking water. In the United States, 50% of the population and 90% of the rural population consume groundwater [1]. One-third of urban water sources in China are also deep well water. Simple and centralized water supply with deep groundwater has become the main form of water diversion in rural areas in China. According to the 1993 rural drinking in the country