Topographic data, aerial imagery, and GPS data collected during uncrewed aircraft system (UAS) operations at Lower Darby Creek, Darby Township, Pennsylvania, March to August 2024

The U.S. Geological Survey deployed small uncrewed aircraft systems (sUAS) to collect aerial remote sensing data across sites within the Lower Darby Creek Superfund Site and the adjacent John Heinz National Wildlife Refuge (JHNWR) ~5 miles outside of Philadelphia, PA in March and August of 2024.  March datasets include aerial images from natural color (RGB) and thermal infra-red (TIR) sensors across the JHNWR and adjacent tributaries as well as the nearby Clearview Landfill within the superfund site.  August datasets include aerial images from natural color (RGB), thermal-infrared (TIR), multispectral sensors, and raw lidar over the Clearview Landfill only.  These datasets were processed to produce high resolution digital elevation models (DEM), image mosaics, and lidar point clouds (LPC).  Black and white cross-coded ground control points (GCPs) were surveyed using Real Time Kinematic (RTK) GPS and RTK-GPS enabled AeroPoints to georeference the model and orthomosaics during post-processing. The elevation and imagery products were produced to help partners at the Environmental Protection Agency (EPA) and U.S. Fish and Wildlife Service (USFWS) acquire accurate elevation data for target sites during the winter "leaf-off" period (March) and monitor changes in vegetation cover during peak growing season (August) building a baseline conditions dataset starting in August 2023.  The March field collection included more baseline lidar data for additional large swaths of the National Wildlife Refuge as well as the thermal imagery dataset, which is the only planned thermal survey, and as a result took several days to complete.  Although lidar was collecting during the August field effort, the focus was for vegetation at the Clearview Landfill and so only required one day of surveying. Future data collections are planned to support long-term monitoring of landscape change resulting from remediation efforts and potential storm impacts.