Spatially-distinct redox conditions and degradation rates following field-scale bioaugmentation for RDX-contaminated groundwater remediation
Autor: | Mark E. Fuller, Mandy M. Michalsen, Jonathan D. Istok, Katarzyna H. Kucharzyk, M.J. Gander, Aaron S. King, Fiona H. Crocker |
---|---|
Rok vydání: | 2019 |
Předmět: |
In situ
Bioaugmentation Environmental Engineering Environmental remediation Health Toxicology and Mutagenesis 0211 other engineering and technologies Pseudomonas fluorescens 02 engineering and technology 010501 environmental sciences 01 natural sciences Bioremediation Explosive Agents TRACER Environmental Chemistry Gordonia Bacterium Waste Management and Disposal Groundwater 0105 earth and related environmental sciences 021110 strategic defence & security studies biology Chemistry Triazines biology.organism_classification Pollution Kinetics Biodegradation Environmental Environmental chemistry Degradation (geology) Water Pollutants Chemical |
Zdroj: | Journal of hazardous materials. 387 |
ISSN: | 1873-3336 |
Popis: | In situ bioaugmentation for cleanup of an hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)-contaminated groundwater plume was recently demonstrated. Results of a forced-gradient, field-scale cell transport test with Gordonia sp. KTR9 and Pseudomonas fluorescens strain I-C cells (henceforth "KTR9" and "Strain I-C") showed these strains were transported 13 m downgradient over 1 month. Abundances of xplA and xenB genes, respective indicators of KTR9 and Strain I-C, approached injection well cell densities at 6 m downgradient, whereas gene abundances (and conservative tracer) had begun to increase at 13 m downgradient at test conclusion. In situ push-pull tests were subsequently completed to measure RDX degradation rates in the bioaugmented wells under ambient gradient conditions. Time-series monitoring of RDX, RDX end-products, conservative tracer, xplA and xenB gene copy numbers and XplA and XenB protein abundance were used to assess the efficacy of bioaugmentation and to estimate the apparent first-order RDX degradation rates during each test. A collective evaluation of redox conditions, RDX end-products, varied RDX degradation kinetics, and biomarkers indicated that Strain I-C and KTR9 rapidly degraded RDX. Results showed bioaugmentation is a viable technology for accelerating RDX cleanup in the demonstration site aquifer and may be applicable to other sites. Full-scale implementation considerations are discussed. |
Databáze: | OpenAIRE |
Externí odkaz: |