The oil pollution of the environment is unfortunately very often reported not only by the Environmental Protections Agency, but also by tourists and environmental NGO. This is a serious problem for the nowadays society, due to their harmful effects even at low concentrations toward the public health. The main sources for oil pollution of ground and surface waters are: oil extraction, transportation and accidental spills in water. The main objective of this study is the development of an inexpensive transducer for the detection of petroleum products, allowing the monitoring of the above mentioned compounds from the ground waters. The working principle of this transducer is based on the modification of the electric permittivity of sorbent media (dielectric) as a result of capillary ascension of petroleum products into the sorbent matrix.