ZONE I SOIL DECONTAMINATION THROUGH IN SITU VAPOR STRIPPING PROCESSES

THE REMEDIATION OF CONTAMINATED SOILS AND GROUNDS TO ENSURE PROTECTION OF PUBLIC HEALTH AND THE ENVIRONMENT IS DIFFICULTAND COSTLY. THERE IS A CRITICAL NEED FOR THE DEVELOPMENT OFTECHNOLOGIES WHICH ARE BOTH TECHNICALLY SOUND AND COST- EFFECTIVE. THE POTENTIAL REMOVAL OF ROGANIC CHEMICALS FROM UNSATURATED SOILS VIA VAPOR PHASE TRANSPORT APPEARS TO SHOW GREAT PROMISE. THIS APPROACH HAS APPLICABILITY BEYOND THE SO-CALLED "VOLATILE ORGANICS", SINCE, IN THE UNSATURATED SOILS AIR AND WATER ARE BOTH PRESENT, AND HIGH MOLECULAR WEIGHT, LOW WATER SOLUBILITY ORGANICS HAVE RELATIVELY HIGH HENRY'S CONSTANTS AND CORRESPONDINGLY HIGH MASS TRANSPORT COEFFICIENTS ACROSS THE WATER/AIR INTERFACE. INVESTIGATIONS OF THE FEASIBILITY OF STRIPPING ORGANIC CONTAMINANTS FROM UNSATURATED SOILS ARE PROPOSED. PHASE I CONSISTS OF LABORA- TORY STUDIES TO CONFIRM FEASIBILITY AND ELUCIDATE PROCESS DYNAMICS. THREE CHEMICALS AND TWO SOIL TYPES WILL BE EXAMINED. THE TOTAL MASS OF CHEMICAL STRIPPED AS A FUNCTION OF TIME BE DETERMINED. THESE DATA WILL IDENTIFY THE POINT AT WHICH VAPOR STRIPPING REACHES DIMINISHING RETURNS AND THECORRESPONDING AMOUNT OF CHEMICAL WHICH IS STILL PRESENT IN THE SOIL SYSTEM. PHASE II WILL PROVIDE ADDITIONAL LABORATORYSTUDIES TO PROVIDE FOR THE DEFINITION OF CRITICAL PROCESS CONTROL PARAMETERS AND FIELD STUDIES AT ACTUAL SITES OF SOILCONTAMINATION.