It’s been a very busy year for Sniffer - especially the last quarter as our team has been darting around the US providing assessments to site owners interested in better understanding the integrity of their landfill’s cover system.
We finished 2020 with a trip to the Caribbean where we demonstrated the efficiency, effectiveness, and safety benefits of using the SnifferDRONE for surface emissions monitoring (SEM) amidst challenging conditions. We also demonstrated our capabilities of providing information on landfill elevated temperatures using an advanced radiometric thermal sensor.
Site Conditions
The subject municipal solid waste (MSW) landfills are located directly off the coast of the Caribbean Sea. With elevation as high as 150', the views of the coast from the top of the landfills were breathtaking. While it was all work / no play, we did enjoy the views, the sea breeze, and even had an opportunity to view a sunrise, and a sunset from these vantage points.
The work zone (footprint) defined by the waste boundary was approximately 60 acres for each site. The sites featured 2:1 slopes that were hazardous to scale and created challenging gusts and updrafts for drone operations from the winds off the coast. Additionally, exposed waste, deep and high vegetation, elevated temperatures with surface fires with ever-present trip, slip, and fall hazards made the operations even more hazardous and challenging.
Manual inspection for gas emissions has been performed in the past by technicians walking the sites. But, due to the site's hazards and challenging conditions, a complete inspection of the site within the waste boundary has not been possible.
One of the landfills where the team operated is directly off the runway of a major island airport. The airspace is classified as Class D (Delta) at 0 feet requiring Sniffer to submit an FAA waiver for any aerial work onsite. The FAA approved our waiver for operation under specific conditions and in coordination with the local air traffic controller (ATC) which allowed us to operate safely onsite.
Scope of Work
The consulting engineer and site owners hired the Sniffer Robotics team to conduct a comprehensive study of methane emissions using the company's SnifferDRONE technology. The desire was for the SnifferDRONE to reach areas that have not been inspected manually and to provide a more detailed analysis of the emissions.
Additionally, the customer requested Sniffer to conduct aerial operations using an advanced radiometric thermal sensor to identify, locate, and provide data associated with elevated surface temperatures within the work zone.
Final written reports providing details for emissions and thermal activity appropriate for analysis and remediation were required. Data and analysis was also to be provided dynamically via Sniffer's Geospatial Portal for a more in-depth review.
SnifferDRONE for Drone-Based Surface Emissions Monitoring (SEM)
It was thought, and we demonstrated, that the SnifferDRONE could minimize safety risks while providing a comprehensive methane emissions analysis of the sites.
In challenging conditions, the SnifferDRONE performed admirably. Normally sites are flown programmatically but these sites required the full attention of the pilot to maneuver around hazards. Therefore x, y pilot control was necessary during the operations but the AGL (z) direction of the drone was fully controlled by our onboard lasers. From the 4K camera mounted onboard the drone the pilot was able to view while flying ground-based obstacles or challenging surface conditions to avoid or areas for further methane emissions data collection by the SnifferDRONE.
The terrain hugging feature of the SnifferDRONE (designed by Sniffer) operated extremely well by appropriately and responsively altering the drone's AGL to maintain the weighted nozzle on the surface despite the severe changes in terrain due to vegetation and surface contours. The ability of the automated z-axis control of the drone can be seen in the video below, especially as the drone turns down the slope of the landfill at the end of the video.
As explained on this page, the SnifferDRONE collects data that can be presented as informational ("Big Picture") or with specific detail that can then be manually verified if required. For this site, we provided a hybrid version as shown in the image below where we identified elevated emissions and localized them to within a 20' radius.
The data collected during our operation was made available to our customer via our dynamic geospatial portal (hosted by ArcGIS) and features multiple layers of data including a high-resolution, basemap, an aggregated qualitative heat-map, specific data measurements plotted by GPS coordinates, and specific locations where high methane readings were recorded.
Radiometric Thermal Imaging
Sniffer was also tasked with performing thermal flyovers of the sites to help identify and locate hot zones. Sniffer has an FAA nighttime waiver that permitted our certified Part 107 remote pilot to fly at night. This allowed us to safely and most effectively conduct operations at the lowest temperature of the day so we can identify areas with the highest variation in temperature referred to as delta-T (∆T).
Our workflow consisted of flying the site in a pre-programmed and controlled manner over the site to collect imagery used to create a thermal reflectance map of the overall site. The result was a qualitative visual of the site from which we were able to identify problematic areas.
During the pre-programmed flights, and from the processed orthomosaic, we were able to identify specific locations that required further investigation and quantitative analysis. We then isolated these specific locations, recording GPS coordinates, surface temperature readings, and additional high-resolution imagery.
The next step was to isolate problematic areas to obtain more detailed imagery, GPS coordinates and quantitative thermal data. An example of one location is provided below.
All visual data was posted within our geospatial portal. From the portal, the customer is able to view all data and imagery together in one location with the ability to either view the information holistically or at a very specific location on the site.
While the conditions of these sites are extreme as compared to the conditions we find at most landfills, the performance of the SnifferDRONE and the team speaks volumes of our capabilities to deliver actionable information to our clients.