“…for 36 Cl -, are taken from the literature (Tertre et al, 2018). Using the initial and boundary conditions from equations 2, 3 and 4, semi-analytical solutions to determine the cumulative activity in downstream reservoirs are given in literature , by Didierjean et al (2004). The semi-analytical solutions were implemented in CEA's Interpretation Model of Diffusion Experiments (I-Mode) tool (Radwan et al, 2006).…”