Accession Number : ADA317432

Title :   Critical Experiments to Determine Feasibility of Organic Contaminant Biodegradation in Cationic Surfactant Treated Media.

Descriptive Note : Final technical rept. 1 May 95-16 May 96,

Corporate Author : SRI INTERNATIONAL MENLO PARK CA

Personal Author(s) : Spanggord, Ronald J. ; Gordon, G. R. ; Mortelmans, Kristien E.

PDF Url : ADA317432

Report Date : SEP 1996

Pagination or Media Count : 35

Abstract : A soil column with 20 sampling ports was designed to assess the binding and potential microbial degradation of naphthalene in Columbus Air Force Base aquifer soil treated with the surfactant, hexadecyltrimethylammonium bromide (HDTMA). HDTMA was found to be toxic to most aerobic soil microorganisms when applied to the soil. However, when the HDTMA was bound to soil, the toxicity decreased and the microbial populations readily recovered to normal levels. Naphthalene was used as a test substrate and was found to readily bind to HDTMA treated soil under anaerobic conditions. When aeration was applied, microbial populations adapted to HDTMA at a faster rate than to the test substrate, naphthalene. This phenomenon caused naphthalene to be desorbed from the soil and naphthalene began to migrate behind metabolized surfactant. Naphthalene metabolism was not observed as assessed by chromatographic analysis of soil sample extracts collected along the column length. Metabolized surfactant was found to leach from the soil column. Under the conditions of this study, it appears that the surfactant technology may have limited utility in soils where pollutant-adapted microbial populations do not recover at sufficient speed to compete with surfactant utilization.

Descriptors :   *SOILS, *CONTAMINANTS, *BROMIDES, *MICROORGANISMS, *NAPHTHALENES, TEST AND EVALUATION, TOXICITY, RATES, SUBSTRATES, METABOLISM, POPULATION, LENGTH, SURFACE ACTIVE SUBSTANCES, BIODEGRADATION, AEROBIC PROCESSES, CHROMATOGRAPHIC ANALYSIS, AERATION, BIODETERIORATION, ANAEROBIC PROCESSES.

Subject Categories : Toxicology
      Microbiology
      Soil Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE