f Application of electrical tomography in environmental study of oil pipeline zone in Luthuanian karst region

The geological and hydrogeological and geomorphological conditions have been investigated along the oil pipeline dislocated in the Northern Lithuanian karst region. The pipeline crosses a region of geological and natural preservation - a zone of intense karstification. A particularly distinct karst structure is being seen between Roveja and Apascia rivers. Karstic subsurface represênts a vulnerable environment, where potable groundwater aquifer can be easily polluted. The objectives were to evaluate already caused and potential damage to nature as weIl as ecological hazards factors in various places along the 18 km long pipeline profile. Electrical tomography measurements have been performed along more than 50 profiles of this region. Also borehole drilling was involved for further interpretation of geoelectrical modeis. 32 control wells up to 20 m deep and 6 wells up to 35 m deep have been drilled.