The organic and inorganic compounds in polluted groundwater are listed in this paper. Some metal iron and nonmetal iron, total dissolved substance and salt accumulate in the groundwater while physical and chemical reaction begin between leachate and soil. This reaction leads to increase in conduction of soil, decrease in resistivity and increase in reflection geoelectrical signals of soil. The results show about 10 Ω·m resistivity values in soil and about 0.40 Ω·m in leachate in two landfill sits in north of China. The results of HDC, TEM and GPR are compared and found that result of HDC is pronounced. Hydrocarbon (freedom CH₄,C₂H₆ absorbed by soil) and fluorescent spectrum are useful geochemical methods for detection of leakage compounds from oil and gas storage reservoirs. We present that anomaly of CH4 is of economy, efficiency and no restriction by the site. But the false signal from animal and plant decomposed must be considered carefully.