Spencer started her journey by analysing the toxicity of these kinds of landfill sites and their effect on the surrounding salt marsh habitats at a site on the Medway estuary, on the other side of the Thames.

Spencer 在开始她的旅程时，通过分析这些垃圾填埋场对泰晤士河对岸梅德韦河口附近盐沼栖息地的毒性和影响，展开了她的研究。