Environmental isotopes as indicators of groundwater recharge, residence times and salinity in a coastal urban redevelopment precinct in Australia

Simple item page
dc.contributor.authorHepburn, Een_AU
dc.contributor.authorCendón, DIen_AU
dc.contributor.authorBekele, Den_AU
dc.contributor.authorCurrell, MJen_AU
dc.date.accessioned2021-11-25T01:55:10Zen_AU
dc.date.available2021-11-25T01:55:10Zen_AU
dc.date.issued2019-12-04en_AU
dc.date.statistics2021-10-14en_AU
dc.description.abstractFishermans Bend is an urban redevelopment precinct situated on the Yarra River estuary in Melbourne, Australia. Understanding the hydrogeological system is important for characterising the impacts from legacy contamination and for monitoring the effects of urbanisation on groundwater flow systems and quality. Stable isotopes of water (δ18O, δ2H) and carbon (δ13C), radioisotopes (3H, 14C) and other geochemical indicators were used to assess sources of water and salinity in the shallow groundwater. Groundwater in the upper aquifer was predominantly Ca-HCO3− dominant, with fresh to brackish salinity—189–3,680 mg/L total dissolved solids (TDS). Localised areas of Ca-SO42− and Na-HCO3− dominant groundwater were impacted by industrial activities and legacy landfills, respectively. Stable isotopes (e.g. δ18O −5.7 to −2.9‰) and tritium activities (1.75–2.45 TU) within the aquifer indicate meteoric water recharged by modern rainfall with short residence times. Carbonate dissolution from shell material, and decay of organic waste and methanogenesis in landfill-leachate-impacted bores were shown to enrich δ13C values up to −4.2‰. In contrast, groundwater in the adjacent/lower aquitard was Na-Cl dominant and saline (19,600–23,900 mg/L TDS), with molar ratios reflective of ocean water, indicating relict emplaced salts. This is consistent with 14C dating of shell material, indicating deposition in a Holocene marine environment. The presence of tritium above background levels (0.20–0.35 TU) in the groundwater, however, suggests a component of modern recharge. Salinity fluctuations within the aquitard at times of peak river level suggest the modern water source is ingress from the adjacent Yarra River. © 2021 Springer Nature Switzerland AG.en_AU
dc.description.sponsorshipFunding for this work was provided by the Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE).en_AU
dc.identifier.citationHepburn, E., Cendón, D. I., Bekele, D., & Currell, M. (2020). Environmental isotopes as indicators of groundwater recharge, residence times and salinity in a coastal urban redevelopment precinct in Australia. Hydrogeology Journal, 28(2), 503-520. doi:10.1007/s10040-019-02077-xen_AU
dc.identifier.issn1435-0157en_AU
dc.identifier.issue2en_AU
dc.identifier.journaltitleHydrogeology Journalen_AU
dc.identifier.pagination503-520en_AU
dc.identifier.urihttps://doi.org/10.1007/s10040-019-02077-xen_AU
dc.identifier.urihttps://apo.ansto.gov.au/dspace/handle/10238/12295en_AU
dc.identifier.volume28en_AU
dc.language.isoenen_AU
dc.publisherSpringer Nature Limiteden_AU
dc.subjectVictoriaen_AU
dc.subjectAustraliaen_AU
dc.subjectRiversen_AU
dc.subjectEstuariesen_AU
dc.subjectGround wateren_AU
dc.subjectStable isotopesen_AU
dc.subjectCarbon isotopesen_AU
dc.subjectSanitary landfillsen_AU
dc.subjectTritiumen_AU
dc.subjectSeasen_AU
dc.subjectSaltsen_AU
dc.subjectSalinityen_AU
dc.titleEnvironmental isotopes as indicators of groundwater recharge, residence times and salinity in a coastal urban redevelopment precinct in Australiaen_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