title: Dating of 'young' groundwaters using environmental tracers: advantages, applications, and research needs.
abstract: Many problems related to groundwater supply and quality, as well as groundwater-dependent ecosystems require some understanding of the timescales of flow and transport. For example, increased concern about the vulnerabilities of 'young' groundwaters (less than ~1000 years) to overexploitation, contamination, and land use/climate change effects are driving the need to understand flow and transport processes that occur over decadal, annual, or shorter timescales. Over the last few decades, a powerful suite of environmental tracers has emerged that can be used to interrogate a wide variety of young groundwater systems and provide information about groundwater ages/residence times appropriate to the timescales over which these systems respond. These tracer methods have distinct advantages over traditional approaches providing information about groundwater systems that would likely not be obtainable otherwise. The objective of this paper is to discuss how environmental tracers are used to characterise young groundwater systems so that more researchers, water managers, and policy-makers are aware of the value of environmental tracer approaches and can apply them in appropriate ways. We also discuss areas where additional research is required to improve ease of use and extend quantitative interpretations of tracer results.
authors.affiliation: Water Resources Programme, International Atomic Energy Agency, Vienna International Centre, Vienna, Austria. b.newman@iaea.org
authors.forename: Brent D
authors.initials: BD
authors.lastname: Newman
authors.forename: Karsten
authors.initials: K
authors.lastname: Osenbrück
authors.forename: Werner
authors.initials: W
authors.lastname: Aeschbach-Hertig
authors.forename: D Kip
authors.initials: DK
authors.lastname: Solomon
authors.forename: Peter
authors.initials: P
authors.lastname: Cook
authors.forename: Kazimierz
authors.initials: K
authors.lastname: Rózański
authors.forename: Rolf
authors.initials: R
authors.lastname: Kipfer
mesh_terms: D004781:Environmental Exposure / Q000032:analysis*; D006291:Health Policy; D007390:International Agencies; D007554:Isotopes / Q000032:analysis*; D011050:Policy Making; D012106:Research / Q000331:legislation & jurisprudence / Q000639:trends; D012107:Research Design; D014872:Water Movements; D014873:Water Pollutants / Q000032:analysis*; D014881:Water Supply / Q000032:analysis*
chemical_list: D007554:Isotopes; D014873:Water Pollutants