Further developments of the L/N ratio after almost 30 years of use

In 1996, at the ISWA conference, Phil Mulvey presented a paper on landfill monitoring introducing an indicator of landfill leachate breakthrough known as the L/N ratio. This indicator substantively reduced the cost of landfill monitoring. Most landfills across Australia now use the L/N ratio albeit calling it the Mulvey ratio, though it is often poorly interpreted for the local setting. In the almost 30 years since publication, as increasing amount of data from vastly different landfill sites becomes available, Phil has further refined how to the use the ratio and how it should be interpreted.

He has also considered the impact of PFAS feedstock on landfill leachate monitoring. Phil presented the theory behind the ratio, the updated amendments, and how to interpret the ratio.