systems it may be used alternatively in conjunction with a destruction system comprising controlled air incinerators coupled between the ground site being detoxified and the off gas system of fig7 particularly in the case where combustion within the hood 28 is not being carried out alternatively ground chemicals may be recovered in a cryogenically cooled condenser or air exchange condenser prior to delivery to the off gas system of fig7 various combinations of gas treating systems of this type can be employed as an alternative embodiment a continuous conduction system may be employed with the electrode configuration depicted in fig1 and 2 wherein an electrically conductive heavy oil is sprayed inserted or injected into the ground for supporting conduction between the electrodes before power is applied a higher current lower voltage source of power is required in such case because of the higher current levels the voltage utilized is suitably between 1 000 and 4 000 volts for supporting a current in the ground between electrodes of between 1600 amps and 450 amps the electrically conductive fluid is suitably sprayed on or inserted into the soil to be treated so that it is absorbed evenly into the soil and the electrodes are then inserted into the soil the electrical conductivity of the fluid will allow sufficient current to pass among the electrodes to dissipate substantial heat in the soil this method is suitable for heating volumes of.