Halon-1301 – further evidence of its performance as an age tracer in New Zealand groundwater

• DOI: 10.5194/hess-2017-80
• Publication Date: 2017-03-15T07:52:36Z
• Authors: Monique Beyer; Uwe Morgenstern; Rob van der Raaij; Heather Martindale
• Keywords: TRACER

Abstract. We recently discovered a new groundwater age tracer, Halon-1301, which can be used to date recharged after the 1970s. In previous study, we showed that Halon-1301 reliably inferred at majority of studied sites. At those sites, ages from agreed with SF6 and tritium, two reliable widely applied tracers. A few samples, however, reduced concentrations preventing meaningful interpretation its concentration. These were likely result degradation or retardation in aquifer. However, couldn’t provide full evidence for this due limited number analysed samples (18 total). assess potential as tracer larger dataset under specific conditions, including highly anoxic young significantly degrade gain more information on magnitude occurrence causes concentrations. 302 SF6, tritium CFCs CFC-11, CFC-12 CFC-113. Comparison these tracers allows assessment performance compared other well established The are taken different environments New Zealand include oxic waters mean residence times ranging