Environmental effects on plants caused by geothermal resource development were studied. Neutron activation method was found
most suitable for this kind of multi-element analysis, and 24 elements could be identified and determined without any chemical
separation. When the amounts of chemical elements detected in plants were plotted against the distance from the source well,
clear correlations sould be observed for Na, Cl, Rb, Cs, As and Sb. Those turned out to be the elements especially concentrated
in the geothermal hot water. From the present studies it was concluded that plants growing within the radius of 300 to 400
meters from the source well were affected by chemical pollutants carried over by mist particles.