College of Geo-exploration Science and Technology��Jilin University��Changchun 130026��China

In order to study the dielectric property of light non-aqueous phase liquid ( LNAPL) contaminated soil��the authors simulate LNAPL contaiminated soil by quartz sand ( particle size 0. 106 �� 0. 212 mm) ��diesel and water under laboratory condition��and then use the open-ended coaxial probe method to detect the dielectric constant in the contaiminated soil by high frequency electromagnetic wave ( 200 MHz �� 3 GHz) and analyze the change regulation of soil-water volume content with the relative dielectric constant�� The experimental results showed that relative dielectric constant of non-saturated quartz sand raised with the increasing of volumetric water content and oil content��but the variation of dielectric constant was not obvious with the increasing of oil content when the sand was saturated�� The relative dielectric constant of the contaminated non-saturated soil increased first��and tended to stable later as time prolonged��