Brownfield Soil Analysis with Laser-Induced Breakdown Spectroscopy

Throughout Miami-Dade County, "brownfields" —areas considered unsafe for development due to high levels of pollutants and contaminants —disrupt and burden residential communities. Low-income communities such as Little Haiti and Homestead are particularly affected, often as a result of industrial developments left abandoned or neglected. To revitalize these communities, brownfields must be safely redeveloped. The soil in these areas can contain arsenic, lead, and other heavy metals that threaten ecosystems and residents. Laser-Induced Breakdown Spectroscopy (LIBS) can be a powerful tool for identifying trace amounts of heavy metals; when the Nd:YAG 1064 nm laser ionizes the surface of a sample, unique spectra are emitted. We analyzed soil samples from undeveloped and redeveloped brownfield sites in Miami-Dade to determine whether potentially hazardous heavy metals were present in the soil. To achieve results with minimal background noise, we prepared samples using a blend of KBr binder and soil and optimized the optical alignment of our LIBS system. This project is part of a broader research effort to introduce high school students to meaningful physics research and ecological work, ensuring that Miami-Dade County's urban areas are being safely redeveloped while uplifting the next generation of physics researchers.