Office/Division Program
OSRR
Project Number
1156
Research Completion Date (POP End)
Research Performing Organization
New Jersey Institute of Technology
Research Principal Investigator
Dr. Michel Boufadel
Research Contracting Agency
Research Contract Award Value
$575,000.00
Description
BSEE Response Research Branch is undertaking the DSD Instrument Evaluation project to better understand how surface water dispersant monitoring, as specified by the NCP SubPart J Monitoring Rule, can be practically implemented with existing technology, with specific emphasis on detection of oil and dispersed oil droplets in depths of 1 to 5 meters.
The three main objectives of this project are:
(1) laboratory validation to test the accuracy of the instruments; (2) tank deployment to test many operational aspects of the instruments, such as the towing capabilities, carriage systems, data processing, etc.; and
(3) field evaluation to test the instruments on a vessel at sea.
Latest progress update
NA
Final Research Abstract
Project 1156 Surface Water Droplet Size Distribution Instrument Laboratory Validation, Tank Deployment, and Field Evaluation
ABSTRACT
Monitoring the use of dispersants on surface oil slicks has been an element of oil spill response in the US since the 1990s. The monitoring has been performed under the guidance of the Special Monitoring of Applied Response Technologies (SMART). The US Environmental Protection Agency (US EPA) released a new Rule specifying monitoring requirements under Subpart J of the National Contingency Plan for dispersant use in response to major oil discharges. The new Subpart J entails, among other things, the measurement and reporting of droplet size distribution (DSD) of oil and dispersed oil. The Laser In-Situ Scattering and Transmissometry (LISST-Black) produced by Sequoia Scientific, and Towed Silhouette Camera (Towed SilCam) produced by SINTEF (Norway) are novel instruments for detecting DSD in oil spill response, whose performance on a fast repeatable and reliable data acquisition is of significant interest. This research conducted two scales of experiment to evaluate the performance of the two instruments, including: 1) a lab-scale experiment with plastic beads at various sizes; and 2) a mesocosm wave tank experiment with crude oil and dispersant. Their results were compared to those collected by a ShadowGraph camera produced by Bellamare (bellamare-us.com), a LISST-200x, and several stand-alone fluorometers. The lab-scale experiment revealed consistent and reliable results obtained by Towed SilCam and the ShadowGraph for individual-sized bead measurement. But when two or three sized beads were used, the Towed SilCam underestimated the bead sizes. LISST-Black overestimated the values of small-sized (<100 μm) beads as there could be overlapping in the laser path. The 200 m long x 20 m wide x 2.5 m deep wave tank results indicated that the peak or near-peak readings from the Towed SilCam and ShadowGraph were comparable. The LISST-Black and LISST-200x data were also similar for chemically dispersed oil. These experiments provided data to help illustrate the optimized DSD detecting ranges for the three instruments. The findings have immediate implications on the application of the Subpart J rule and oil spill response.
Key Words: oil spill response, surface oil monitoring, droplet size distribution, fluorometry, dispersant.
Boufadel MC, Ji W, Qu Z, Liu R. (NJIT, Newark NJ), 2024. Surface water droplet size distribution instrument laboratory validation, tank deployment, and field evaluation written abstract. Sterling (VA): US Department of the Interior, Bureau of Safety and Environmental
Enforcement. 2 p. Report No. 1156 Contract No.: 140E0123C0007. https://doi.org/10.70149/0000001156
ABSTRACT
Monitoring the use of dispersants on surface oil slicks has been an element of oil spill response in the US since the 1990s. The monitoring has been performed under the guidance of the Special Monitoring of Applied Response Technologies (SMART). The US Environmental Protection Agency (US EPA) released a new Rule specifying monitoring requirements under Subpart J of the National Contingency Plan for dispersant use in response to major oil discharges. The new Subpart J entails, among other things, the measurement and reporting of droplet size distribution (DSD) of oil and dispersed oil. The Laser In-Situ Scattering and Transmissometry (LISST-Black) produced by Sequoia Scientific, and Towed Silhouette Camera (Towed SilCam) produced by SINTEF (Norway) are novel instruments for detecting DSD in oil spill response, whose performance on a fast repeatable and reliable data acquisition is of significant interest. This research conducted two scales of experiment to evaluate the performance of the two instruments, including: 1) a lab-scale experiment with plastic beads at various sizes; and 2) a mesocosm wave tank experiment with crude oil and dispersant. Their results were compared to those collected by a ShadowGraph camera produced by Bellamare (bellamare-us.com), a LISST-200x, and several stand-alone fluorometers. The lab-scale experiment revealed consistent and reliable results obtained by Towed SilCam and the ShadowGraph for individual-sized bead measurement. But when two or three sized beads were used, the Towed SilCam underestimated the bead sizes. LISST-Black overestimated the values of small-sized (<100 μm) beads as there could be overlapping in the laser path. The 200 m long x 20 m wide x 2.5 m deep wave tank results indicated that the peak or near-peak readings from the Towed SilCam and ShadowGraph were comparable. The LISST-Black and LISST-200x data were also similar for chemically dispersed oil. These experiments provided data to help illustrate the optimized DSD detecting ranges for the three instruments. The findings have immediate implications on the application of the Subpart J rule and oil spill response.
Key Words: oil spill response, surface oil monitoring, droplet size distribution, fluorometry, dispersant.
Boufadel MC, Ji W, Qu Z, Liu R. (NJIT, Newark NJ), 2024. Surface water droplet size distribution instrument laboratory validation, tank deployment, and field evaluation written abstract. Sterling (VA): US Department of the Interior, Bureau of Safety and Environmental
Enforcement. 2 p. Report No. 1156 Contract No.: 140E0123C0007. https://doi.org/10.70149/0000001156