Figure 2: Different sources of mixing scenarios
  1. Sink classification

    Classification of sinks to contaminant cascades
Chin et al. [27] proposed an indicator to identify the sinks’ contaminant cascades and limiting contaminants. For a problem with ’k’ contaminants with ’N’ internal sources, assuming a single sink (SK1), the real freshwater target is shown in Eq (3) – see the derivation in Appendix A- Eq (A13). To identify the preferred source ranking for the specific sink, the ratio of sink concentration to the source concentration play an important role. It has been proposed that the largest source concentration of contaminant ’k’ (Ck,SR_max) is used because it also shows exactly the prioritisation of sources if more than two sources are used. For example, if the coefficient of FSR1,SK1 is more negative than FSR2,SK1, then SR1 should be prioritised. The maximum source concentration can also be treated as a normalisation constant.