Abstract: A method and apparatus are provided for remediation of near surface soils, pavements and other surfaces using a radiant heating plate, an insulating layer, and a vapor barrier above the radiant heating plate and below the insulation. The radiant heating plate transfers thermal energy to the surface primarily by radiation and therefore need not be in contact with the surface over large areas. The radiant heating plate may also serve as a vacuum barrier for collecting contaminant vapors emanating from the subsurface soil.

Abstract: This invention comprises a surface heating blanket assembly useful for soil remediation. The assembly principally comprises a metallic furnace belt with tubular electric heating elements inserted between the rungs thereof and making low resistance contact therewith. The furnace belt heater is capable of being rolled and dragged, and flexibly conforms to the earth's surface for maximum heat transfer to the soil. A layer of permeable insulation and an impermeable sheet may be placed on top of the heater. A vacuum may be pulled under the impermeable layer by means of a hole therethrough connected to a vacuum pump.

Abstract: A control system which minimizes the start up time of heaters and sustains long term automatic control is provided. This control system automatically converts control time constant current to constant power when the power reaches the power set and provides that after power interruptions, control will revert back to constant current until constant power control is again called for. The heater controlled by the control system of this invention is preferably a subterranean heater having a long heating element.

Abstract: Methods and apparatuses to measure RMS current, RMS voltage, and true power for zero-fired alternating current loads are provided. These methods and apparatuses are simple and inexpensive and provide updated measurements after each set of blocked or unblocked alternating current cycles.