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Title: Stabilization of Plutonium in Subsurface Environments via Microbial Reduction and Biofilm Formation

Abstract

Plutonium has a long half-life (2.4 x 104 years) and is of concern because of its chemical and radiological toxicity, high-energy alpha radioactive decay. A full understanding of its speciation and interactions with environmental processes is required in order to predict, contain, or remediate contaminated sites. Under aerobic conditions Pu is sparingly soluble, existing primarily in its tetravalent oxidation state. To the extent that pentavalent and hexavalent complexes and small colloidal species form they will increase the solubility and resultant mobility from contamination sources. There is evidence that in both marine environments and brines substantial fractions of the plutonium in solution is present as hexavalent plutonyl, PuO2 2+.

Authors:
; ; ;
Publication Date:
Research Org.:
Los Alamos National Laboratory (LANL), Los Alamos, NM
Sponsoring Org.:
USDOE
OSTI Identifier:
925441
Report Number(s):
CONF-ERSP2007/1024817
R&D Project: ERSD 1024817; TRN: US0802290
Resource Type:
Conference
Resource Relation:
Conference: Annual Environmental Remediation Science Program (ERSP) Principal Investigator Meeting, April 16-19, 2007, Lansdowne, VA
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; AEROBIC CONDITIONS; BRINES; CONTAMINATION; PLUTONIUM; SOLUBILITY; STABILIZATION; BIOREMEDIATION; PLUTONIUM OXIDES; RADIONUCLIDE MIGRATION

Citation Formats

Hakim Boukhalfa, Gary A. Icopini, Sean D. Reilly, and Mary P. Neu. Stabilization of Plutonium in Subsurface Environments via Microbial Reduction and Biofilm Formation. United States: N. p., 2007. Web.
Hakim Boukhalfa, Gary A. Icopini, Sean D. Reilly, & Mary P. Neu. Stabilization of Plutonium in Subsurface Environments via Microbial Reduction and Biofilm Formation. United States.
Hakim Boukhalfa, Gary A. Icopini, Sean D. Reilly, and Mary P. Neu. Thu . "Stabilization of Plutonium in Subsurface Environments via Microbial Reduction and Biofilm Formation". United States. doi:. https://www.osti.gov/servlets/purl/925441.
@article{osti_925441,
title = {Stabilization of Plutonium in Subsurface Environments via Microbial Reduction and Biofilm Formation},
author = {Hakim Boukhalfa and Gary A. Icopini and Sean D. Reilly and Mary P. Neu},
abstractNote = {Plutonium has a long half-life (2.4 x 104 years) and is of concern because of its chemical and radiological toxicity, high-energy alpha radioactive decay. A full understanding of its speciation and interactions with environmental processes is required in order to predict, contain, or remediate contaminated sites. Under aerobic conditions Pu is sparingly soluble, existing primarily in its tetravalent oxidation state. To the extent that pentavalent and hexavalent complexes and small colloidal species form they will increase the solubility and resultant mobility from contamination sources. There is evidence that in both marine environments and brines substantial fractions of the plutonium in solution is present as hexavalent plutonyl, PuO2 2+.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Apr 19 00:00:00 EDT 2007},
month = {Thu Apr 19 00:00:00 EDT 2007}
}

Conference:
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  • The overarching goal of this research project is to investigate and optimize the mechanisms for in situ immobilization of Pu species by naturally-occurring bacteria. Specific research objectives are: (a) investigate the mechanism of bacterial accumulation and immobilization of plutonium species by biofilm formation under aerobic conditions and (b) to demonstrate the direct and indirect stabilization of Pu via dissimilatory reduction by Geobacter metallireducens.
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