Identification of sources and processes in a low-level radioactive waste site adjacent to landfills: groundwater hydrogeochemistry and isotopes

Simple item page
dc.contributor.authorCendón, DIen_AU
dc.contributor.authorHughes, CEen_AU
dc.contributor.authorHarrison, JJen_AU
dc.contributor.authorHankin, SIen_AU
dc.contributor.authorJohansen, MPen_AU
dc.contributor.authorPayne, TEen_AU
dc.contributor.authorWong, HKYen_AU
dc.contributor.authorRowling, Ben_AU
dc.contributor.authorVine, Men_AU
dc.contributor.authorWilsher, KLen_AU
dc.contributor.authorGuinea, Aen_AU
dc.contributor.authorThiruvoth, Sen_AU
dc.date.accessioned2021-12-16T06:15:13Zen_AU
dc.date.available2021-12-16T06:15:13Zen_AU
dc.date.issued2014-11-25en_AU
dc.date.statistics2021-10-29en_AU
dc.description.abstractMultiple tracer-element and isotope approaches were applied at a 1960s-era low-level radioactive waste burial site located in the Lucas Heights area on the southwest urban fringe of Sydney, Australia. The site is situated among other municipal and industrial (solid and liquid) waste disposal sites causing potential mixing of leachates. Local rainfall contains marine-derived major ion ratios that are modified during infiltration depending on waste interactions. The local geology favours the retention of contaminants by ion-exchange processes within the clay-rich soils and the shale layer underlying the burial site. Local soils experience periodic infiltration and wetting fronts that can fully saturate the waste trenches (bathtub effect) while surrounding soils are mostly unsaturated with discontinuous perched lenses. Within the trenches, the degradation of organic matter results in localised methanogenesis, as suggested by enriched δ2H and δ13CDIC values in adjacent subsurface water. Movement of contaminants from the trenches is indicated by Na+, Br? and I? concentrations, variations in 87Sr/86Sr, enriched δ13CDIC values and evolution of δ34S of dissolved sulfate in perched water bodies above the shale. Although transport is limited by the low transmissivity of the clay-rich soils, migration and mixing processes are indicated by the variation of concentrations with distance from the trenches, disappearance of δ2H enrichments, mixing with other sources of Sr and sulfate isotope fractionations. The depth distribution of waste-derived contaminants (specifically 3H and Be) between the perched water surrounding the trenches, and the underlying shale and sandstone layers, indicates limited downward transport of contaminants. Past removal of the shale layer in an adjacent site, Harrington's Quarry, has facilitated the mixing of some municipal waste leachates (characterised by circum-neutral pH, high alkalinity, low sulfate, high 3H, high Be, enriched δ2H and δ13CDIC) into the underlying groundwater system as suggested by high TDS, Cl?/Br? ratios, Be and 3H found in deeper wells. This study demonstrates the applicability of using trace elements, stable- and radio-isotopes to document the existing geochemistry and the contaminant transport from the waste trenches. The multiple tracer approach addresses the complexities of transport at the site and differentiates various municipal, industrial and radioactive waste sources. © 2014 Informa UK Limiteden_AU
dc.description.sponsorshipSpanish government grant (CGL2009-11096)en_AU
dc.identifier.citationCendón, D. I., Hughes, C. E., Harrison, J. J., Hankin, S. I., Johansen, M. P., Payne, T. E., Wong, H., Rowling, B., Vine, M., Wilsher, K., Guinea, A., & Thiruvoth, S. (2015). Identification of sources and processes in a low-level radioactive waste site adjacent to landfills: groundwater hydrogeochemistry and isotopes. Australian Journal of Earth Sciences, 62(1), 123-141. doi:10.1080/08120099.2015.975155en_AU
dc.identifier.issn0812-0099en_AU
dc.identifier.issue1en_AU
dc.identifier.journaltitleAustralian Journal of Earth Sciencesen_AU
dc.identifier.pagination123-141en_AU
dc.identifier.urihttps://doi.org/10.1080/08120099.2015.975155en_AU
dc.identifier.urihttps://apo.ansto.gov.au/dspace/handle/10238/12501en_AU
dc.identifier.volume62en_AU
dc.language.isoenen_AU
dc.publisherTaylor & Francis Groupen_AU
dc.subjectRadioactive wastesen_AU
dc.subjectRadioactive waste disposalen_AU
dc.subjectGround disposalen_AU
dc.subjectWaste burialen_AU
dc.subjectIsotopesen_AU
dc.subjectGround wateren_AU
dc.subjectNew South Walesen_AU
dc.subjectGround wateren_AU
dc.subjectANSTOen_AU
dc.titleIdentification of sources and processes in a low-level radioactive waste site adjacent to landfills: groundwater hydrogeochemistry and isotopesen_AU
dc.typeJournal Articleen_AU
Files
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
1.63 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Journal Articles