The Shoreline Cleanup Assessment Technique (SCAT) was created as a systematic way to survey shorelines affected by spilled oil. SCAT begins in the early stages of a response to assess initial shoreline conditions and continues throughout cleanup activities until final signoff. Traditional SCAT teams survey shorelines by boat or on foot, but some areas, like sensitive marsh environments, are difficult to access using these methods. New methods for conducting SCAT surveys were employed during a recent oil spill response to a wellhead blowout in the marshes of Louisiana’s Pass A Loutre State Wildlife Management Area.

 After initial overflights were conducted from traditional aircraft to define the incident impact area, multiple UAS missions were flown over the site to collect orthomosaic imagery of all the shorelines and marsh habitats affected. A battery-charging station allowed the UAS team to continually fly with minimum downtime, covering 1800 acres of marsh in just 14 hours over 2 days. Images were processed into orthomosaics while still in the field and then uploaded into the Common Operating Picture (COP) to help direct response operations. Additionally, the UAS orthomosaics successfully captured floating oil and sheens on the water between marshes.

Due to the success of the reconnaissance UAS missions, it was decided that the SCAT process would also be conducted by collecting UAS orthomosaics over the impacted shorelines. Trained SCAT teams reviewed the orthomosaics in a GIS and characterized the presence of oil by editing attributes in an online feature service representing the shoreline, a process similar to conducting traditional SCAT surveys in the field by recording observations on paper forms. The process was reviewed by experienced SCAT personnel and lessons learned during this incident will be used to make improvements for future responses.