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Title: Natural analogue studies as supplements to biomineralization research

Abstract

Chemical reactions can alter the chemistry and crystal structure of solid objects over archeological or geological times, while preserving external physical shapes. The reactions resulting in these structures offer natural analogues to laboratory experiments in biomineralization and to biologically influenced alteration of nuclear waste packages, and thus, they offer the only available way of validating models that purport waste package behavior over archaeological or geological times. Potential uses of such analogues in the construction and validation of hypothetical mechanisms of microbiological corrosion and biomineralization are reviewed. Evidence from such analogues suggests that biofilms can control materials alteration in ways usually overlooked. The newly hypothesized mechanisms involve control by biofilms of the cation flow near the solid surface and offer plausible mechanisms for the formation of mixed-cation minerals under conditions that would lead to dealloying in abiotic experiments; they also account for the formation of unusual minerals [such as posnjakite, Cu{sub 4}SO{sub 4}(OH){sub 6{center_dot}}H{sub 2}O] and mineral morphologies unusual in corrosion [malachite, Cu{sub 2}CO{sub 3}(OH){sub 2}, rarely forms botryoidally under corrosion conditions and its occasional presence on archaeological objects that appear to have undergone microbiological corrosion may be related to biofilm phenomena].

Authors:
 [1]
  1. Nuclear Regulatory Commission, Washington, DC (United States)
Publication Date:
Research Org.:
Nuclear Regulatory Commission, Washington, DC (United States). Div. of Regulatory Applications; Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses
OSTI Identifier:
146989
Report Number(s):
NUREG/CP-0147; CONF-9107285-; CNWRA-93-020
ON: TI96001409; TRN: 96:001447
Resource Type:
Conference
Resource Relation:
Conference: Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste, San Antonio, TX (United States), 22-25 Jul 1991; Other Information: PBD: Sep 1995; Related Information: Is Part Of Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste: Proceedings; Kovach, L.A. [ed.] [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Regulatory Applications]; Murphy, W.M. [ed.] [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses]; PB: 120 p.
Country of Publication:
United States
Language:
English
Subject:
05 NUCLEAR FUELS; 42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; HIGH-LEVEL RADIOACTIVE WASTES; RADIOACTIVE WASTE DISPOSAL; UNDERGROUND DISPOSAL; PACKAGING; NATURAL ANALOGUE; USA; RADIOACTIVE WASTE MANAGEMENT; CONTAINERS; PERFORMANCE; CORROSION

Citation Formats

McNeil, M.B. Natural analogue studies as supplements to biomineralization research. United States: N. p., 1995. Web.
McNeil, M.B. Natural analogue studies as supplements to biomineralization research. United States.
McNeil, M.B. 1995. "Natural analogue studies as supplements to biomineralization research". United States. doi:. https://www.osti.gov/servlets/purl/146989.
@article{osti_146989,
title = {Natural analogue studies as supplements to biomineralization research},
author = {McNeil, M.B.},
abstractNote = {Chemical reactions can alter the chemistry and crystal structure of solid objects over archeological or geological times, while preserving external physical shapes. The reactions resulting in these structures offer natural analogues to laboratory experiments in biomineralization and to biologically influenced alteration of nuclear waste packages, and thus, they offer the only available way of validating models that purport waste package behavior over archaeological or geological times. Potential uses of such analogues in the construction and validation of hypothetical mechanisms of microbiological corrosion and biomineralization are reviewed. Evidence from such analogues suggests that biofilms can control materials alteration in ways usually overlooked. The newly hypothesized mechanisms involve control by biofilms of the cation flow near the solid surface and offer plausible mechanisms for the formation of mixed-cation minerals under conditions that would lead to dealloying in abiotic experiments; they also account for the formation of unusual minerals [such as posnjakite, Cu{sub 4}SO{sub 4}(OH){sub 6{center_dot}}H{sub 2}O] and mineral morphologies unusual in corrosion [malachite, Cu{sub 2}CO{sub 3}(OH){sub 2}, rarely forms botryoidally under corrosion conditions and its occasional presence on archaeological objects that appear to have undergone microbiological corrosion may be related to biofilm phenomena].},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1995,
month = 9
}

Conference:
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  • Colloids may be important as a geochemical transport mechanism for radionuclides at geological repositories if they are (1) present in the groundwater, (2) stable with respect to both colloidal and chemical stabilities, (3) capable of adsorbing radionuclides, especially if the sorption is irreversible, and (4) mobile in the subsurface. The available evidence from natural analogue and other field studies relevant to these issues is reviewed, as is the potential role of mobile microorganisms ({open_quotes}biocolloids{close_quotes}) on radionuclide migration. Studies have demonstrated that colloids are ubiquitous in groundwater, although colloid concentrations in deep, geochemically stable systems may be too low to affectmore » radionuclide transport. However, even low colloid populations cannot be dismissed as a potential concern because colloids appear to be stable, and many radionuclides that adsorb to colloids are not readily desorbed over long periods. Field studies offer somewhat equivocal evidence concerning colloid mobility and cannot prove or disprove the significance of colloid transport in the far-field environment. Additional research is needed at new sites to properly represent a repository far-field. Performance assessment would benefit from natural analogue studies to examine colloid behavior at sites encompassing a suite of probable groundwater chemistries and that mimic the types of formations selected for radioactive waste repositories.« less
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