EFFECTS OF COSOLVENT ADDITIONS ON THE BIODEGRADABILIITY OF HIGH MOLECULAR WEIGHT PAH COMPOUNDS IN SOIL

ADDITION OF COSOLVENTS TO WATER INCREASES THE SOLUBILITY OF HYDROPHOBIC CONTAMINANTS BY SHIFTING THE ADSORPTION EQUILIBRIUM TO FAVOR HIGHER AQUEOUS PHASE CONCENTRATIONS. INCREASING THEIR WATER SOLUBILITY MAKES CONTAMINANTS MORE ACCESSIBLE FOR BIODEGRADATION. WHILE IT IS OFTEN SPECULATEDTHAT LOW RATES OR LACK OF BIODEGRADATION IS CAUSED BY LOW AQUEOUS SOLUBILITY, NO STUDIES HAVE BEEN PERFORMED TO DATE TO DETERMINE WHETHER COSOLVENTS CAN ELICIT A BIODEGRADATION RESPONSE IN SAMPLES THAT WERE PRESUMABLY SORPTION LIMITED. THE PROPOSED STUDY WILL DETERMINE THE EFFECTS OF COSOLVENTS ON BIODEGRADATION OF HIGH MOLECULAR WEIGHT POLYNUCLEAR AROMATIC HYDROCARONS IN SAMPLES WHERE NO BIODEGRADATION WAS PREVIOUSLY OBSERVABLE, PRESUMABLY DUE TO ORGANIC-PHASE PARTITIONING. THE RESULTS OF THE STUDY WILL THEORETICALLY PROVIDE A NEW COSOLVENT-ENHANCED BIOREMEDIATION PROCEDURE THAT IS ECONOMICALLY ADVANTAGEOUS OVER ALTERNATIVE TECHNOLOGIES WHERE BIOREMEDIATION ALONE IS INADEQUATE TO ACHIEVE ASSIGNED CLEANUP CRITERIA.