PRACTICAL APPLICATIONS OF AIRBORNE LIDAR DATA FOR ENVIRONMENTAL AND ENGINEERING GEOLOGY PROJECTS

Over the past decade there has been a significant increase in the use of airborne LiDAR (Light Detection and Ranging) data to create detailed topographic base maps and high-resolution (0.2 - 1 m vertical accuracy) digital elevation models (DEMs) for a variety of regional and site-specific projects. If the scope of data acquisition is properly defined and implemented, LiDAR is effective in all types of terrain and vegetation; however it is particularly useful in densely vegetated areas where conventional photogrammetry-based topographic maps and resulting DEMs have a relatively low accuracy. In addition, it is very cost-effective in steep or remote terrain that cannot be easily surveyed by conventional methods. In addition to the common use of LiDAR for assessing geohazards, it has been successfully used for variety of consulting environmental and engineering geology projects including:

• Baseline data for timber sale areas
• Karst sinkhole mapping
• Unexploded ordinance range mapping
• Structural geologic mapping of an inaccessible rock avalanche
• Mine tailing and landslide debris volume estimates
• Levee evaluation
• Detailed topography for surface water- groundwater interaction for a contaminant plume
• Wetlands hydrology

Lessons learned regarding acquisition and QA/QC review of LiDAR data, management of LiDAR vendors, managing large LiDAR data sets, and automation of LiDAR data processing will also be summarized.