Monitoring of ground subsidence in Orlando coal ash landfills using Sentinel-1 PSInSAR

Globally, coal is a major mineral used in energy production, and Coal ash is produced in energy production. Coal ash pollutes the environment and causes health problems for humans. Therefore, it is important to store coal ash, most of the coal ash is stored in landfills. Landfills ground subside over time, and ground subsidence is one of the main factors in landfills stability. Therefore, it is important to understand the stability of coal ash landfills, so we would like to monitor coal ash landfills through remote sensing methods. In this study, the Stanton Energy Center, a coal-fired power plant in Orlando, Florida, in the southeastern United States, was selected as a research area. The Stanton energy center stored coal ash in a landfill next to the power plant and installed solar panels on top of the coal ash landfill in 2017. In this study, the Sentinel-1 satellite provided by the European Space Agency (ESA) was used, and ascending data was obtained between June 2018 and 2022. Digital Elevation Model (DEM) used for image processing used LIDAR DEM images with 1 m spatial resolution provided by the United States Geological Survey (USGS). PSInSAR image preprocessing used SNAP software provided by European Space Agency (ESA), and PSInSAR process used Standard Method of Persistent Scatterers (StaMPS). The PSInSAR result using Copernicus 30 DEM in the coal landfill area confirmed about 50 mm subsidence for 5  years in the LOS direction, and the PSInSAR result using Lidar DEM confirmed about 45 mm subsidence for 5 years in the LOS direction. In addition, the PSInSAR results in a stable area located near the landfill confirmed that there was little subsidence in the LOS direction for 5 years.