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All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Nuclear Data Needs for Radiochemistry

There are many elements of interest to the weapons community that include light elements, activation products, fission products, actinides and heavy elements. Of course, that is the whole periodic table! In this memo we summarize a down-selected list, 22 of 118+ of elements that have or could serve as radiochemical diagnostic measurements. The simulations would need cross sections for nuclides (and metastable states) of these elements to be able to calculate values for comparison with debris measurements.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2021

Crack Stability in Breached Fuel

This report describes the fracture mechanics formalism to evaluate the stability of cracks in a fuel cladding. Recognized consensus-body linear elastic fracture mechanics (LEFM) was applied to identify the crack instability length, or the length at which unstable mechanical crack extension would occur, as a function of pellet swelling loading (radial strain and fraction conversion from UO 2 to U 3 O 8 ) at the local cracked cladding region for two postulated fracture toughness (K IC ) values of the cladding. The crack opening displacement (COD) and the crack opening area (COA) were also identified. This analysis informs evaluations for crack extension and the potential for pellet debris loss from the fuel rod for cases of pellet oxidation in dry storage canisters where inadvertent residual water may undergo radiolysis causing oxidizing conditions to pellets exposed to the canister environment through breached cladding.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Represent precipitation-induced geological hazards in Earth system models using artificial intelligence

Precipitation-induced geological hazards, such as debris flow, landslides, mudflow and rockfalls (hereafter referred to as landslides), pose serious threats to public safety in many areas through the world. As residential properties and infrastructure in the US have increasingly expanded into landslide-prone areas and the drivers of landslides (e.g., wildfires and hurricanes) are predicted to intensify under climate warming, losses and fatalities from landslides are likely to increase in the future. Although our understanding of geoenvironmental factors and mechanisms contributing to landslides has greatly improved, only moderate progress has been made in predicting landslides out of well-studied watersheds. Furthermore, explicitly representing various landslide-related processes in Earth system models (ESMs), from the buckling of local bearing elements in granular materials, to frictional sliding between grains, formation of microcracks in the soil matrix, rupture of capillary bridges, or breakage of plant roots3 is still very unlikely within the next decade, even with the help of exascale computers.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Systems Engineering Approach for Design and Implementation of a Gas Breech for Actinide Experiments at the JASPER Facility

The Joint Actinide Shock Physics Experimental Research (JASPER) Facility is located approximately 65 miles north of Las Vegas, Nevada at the Nevada National Security Site (NNSS). The primary mission is to conduct shock physics research on actinide materials in support of NNSA’s Stockpile Stewardship Program. JASPER experiment uses a two-stage light gas gun to accelerate projectiles into targets at velocities up to 8 km/s (17,000 mph). The first stage uses an ignited propellent to drive a piston to compress gas in the pump tube. At the second stage, the gas compression exceeds a specified pressure and a rupture valve at the end of the pump tube opens. This launches a projectile to impact the target. The target is housed inside the target assembly and the debris field is contained inside the primary target chamber (PTC). The PTC is placed inside the secondary confinement chamber (SCC) as an added protection against possible contamination. These major components are illustrated in Figure 1.JASPER is capable of generating and measuring data on the properties of radioactive chemical elements at high shock pressures, temperatures, and strain rates approximating the conditions in nuclear weapons by using a two-stage gas gun. The data is used to determine material equations-of-state and validate computer models of material response. The work advances predictive capability, thus ensuring confidence in the nuclear stockpile.

42 ENGINEERING↗
DOE OSTI2019

Closure Report for Corrective Action Unit 414: Clean Slate III Plutonium Dispersion (TTR) Tonopah Test Range, Nevada

The purpose of this CR is to provide documentation and justification for the clean closure of CAU 414 under the FFACO without further corrective action. This justification is based on historical knowledge of the site, previous site investigations, closureactivities conducted at the site, and the results of verification samples. Clean closure activities included excavating and disposing of radiologically contaminated soil and debris in the vicinity of ground zero, and collecting verification samples to support the corrective action of clean closure. Results confirmed that further corrective action is not required at CAU 414. Based on the corrective action activities conducted, clean closure of the site is complete; the closure objectives established in the CADD/CAP have been achieved; and no further corrective action at the site is required.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Analysis of microplastics in bivalves along Fourmile Branch

Microplastics are commonly found near wastewater treatment facilities with the source originating typically from fibers associated with laundry detergents. Fourmile branch would have limited laundry associated effluent and does not receive any input from water originating from upstream industry sources, therefore microplastics would have originated from Site operations or through atmospheric deposition which are both unexplored pathways. In order to assess environmental inventory effects on the biota, water samples were collected from sampling locations along Fourmile Branch on the Savannah River Site using plankton nets and grab samples at Fourmile Branch locations (i.e., FM-2B, FM-A7, and FM6). Fourmile Branch has a long history of receiving industrial effluents from site operations as well effluent from the site’s wastewater treatment plant. Water samples and the debris collected in the nets were rinsed with deionized water and sieved to remove the larger fractions of plastics (4000-2000 µm) and retain fractions <500 µm. The water samples were analyzed for the type and size of plastics by μ-Raman, mass spectrometry, and Fourier Transform Infrared Spectroscopy (FTIR) methods. Previously collected bivalves were prepared into thin sections and analyzed using microscopy.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Requirements Documents for the Large Mechanical Parts Precision Cleaner (LMPPC) in the Optics Assembly Building (OAB)

The National Ignition Facility (NIF) is the world's largest energetic laser whose missions include sresearch in inertial confinement fusion, experiments for the Stockpile Stewardship, and other high fluence laser research. Due to the high fluence of lasers, extreme environmental conditions, and radiation presence, all mechanical parts (metal, plastic, etc.) installed on NIF must be precision cleaned. Precision cleaned parts are also required in supporting facilities like the Optics Processing Facility (OPF). Small debris inside the laser beams or on optics can cause optic damage, interfere with diagnostics, and interfere with experiments.

42 ENGINEERING↗
DOE OSTI2022

U.S. Efforts in Support of Examinations at Fukushima Daiichi (November 2021 Meeting Notes with Updated Information Requests)

Information obtained from Fukushima Daiichi Nuclear Power Station (Daiichi) is required to inform future Decontamination and Decommissioning (D&D) activities, improving the ability of the Tokyo Electric Power Company Holdings, Incorporated (TEPCO Holdings) to characterize potential hazards and to ensure the safety of workers involved with cleanup activities. This information also has important implications for the safety and operation of U.S. commercial nuclear power plants. This document summarizes results from the Fiscal Year 2022 (FY2022) U.S. effort to review Daiichi information and extract insights to enhance the safety of existing and future nuclear power plant designs. This U.S. effort, which was initiated in 2014 by the Department of Energy Office of Nuclear Energy, is completed by a group of experts in reactor safety and plant operations that identify examination needs and evaluate recent Daiichi examination data to address these needs. Fukushima-related information and associated discussions during forensics meetings benefit operating, new, and advanced reactors. Significant safety insights are being obtained in several areas: system and component performance, radionuclide surveys and sampling, debris end-state location, combustible gas effects, and plant operations and maintenance. In addition to reducing uncertainties related to severe accident modeling progression, these insights have and continue to be used to update guidance for severe accident prevention, mitigation, and emergency planning. As discussed in this document, revised operator guidance was successfully used to improve operator response during a loss of off-site power event at the Duane Arnold Energy Center plant. Reduced uncertainties in modeling the events at Daiichi improve the realism of reactor safety evaluations that inform future D&D activities. U.S. evaluations of information from Fukushima and input regarding future examinations are of interest to several organizations within Japan. Meeting presentations by Japan describe how comments and recommendations documented in prior U.S. forensics effort reports, including consensus information requests developed by forensics effort participants, are considered in future Fukushima D&D activities. As discussed in this report, TEPCO Holdings considered these information requests in their D&D planning activities. An updated list of consensus information requests is included in this FY2022 report.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2022

Non-Powered Dam Retrofit Exemplary Design for Hydropower Applications

Non-powered dams (NPDs) represent complex systems, situated at the intersection of natural stream environments and the built environment. The presence and operations of NPDs affect stream constituents (e.g., fish, recreational craft, sediment, water) and serve one or more engineered purposes (e.g., recreation, flood control, water supply, irrigation, tailings and debris control, navigation). By definition, NPDs do not provide hydropower generation. However, every NPD contains some untapped hydropower resource potential, represented by the pre-existing hydraulic head created by the dam and presence of flowing water. Adding power generation to an NPD requires retrofitting the NPD, which could involve the addition of any new component or function beyond that currently installed. Because this research is funded by the US Department of Energy Water Power Technologies Office, adding hydropower to NPDs is among the primary objectives for research investment. However, NPD retrofitting extends beyond the purview of hydropower additions. This report provides background information regarding NPD development in the United States, including an overview of the US NPD population, development potential, and recent development. It also summarizes challenges and opportunities facing NPD retrofit development, highlights the importance of maintaining or improving stream and dam functionality, notes key NPD characteristics, describes NPD retrofit methods, and identifies innovation areas for spurring future NPD retrofit development. Section 4 describes retrofit exemplary design principles and concepts that could apply to a wide range of NPD projects. These principles and concepts inform an NPD Retrofit Exemplary Design Specification (REDS), as included in Appendix A. The NPD REDS is heavily influenced by prior work under the standard modular hydropower technology acceleration research initiative, especially the work documented in the Exemplary Design Envelope Specification for Standard Modular Hydropower Technology (Witt et al., 2017). Whereas this prior work focuses on a particular technology class that applies most intentionally for new stream-reach development (i.e., greenfield sites), the NPD REDS contained herein applies more broadly to the NPD resource class and is technology-agnostic (i.e., the specific technologies intended to be described are not explicitly prescribed). This report serves as a part of early-phase research on NPD retrofit development, aimed toward spurring additional, follow-on efforts to specifically address development challenges, capitalize on development opportunities, and inspire innovation. As documented in the landmark “Hydropower Vision” report (DOE 2016), “transformative technical innovations able to meet the co-objectives of environmental sustainability and low-carbon energy will be critical to enabling additional hydropower growth.” This report serves as an important step in steering transformation of US non-powered dam infrastructure.

13 HYDRO ENERGY↗
DOE OSTI2022

Direct Laser Impulse (DLI) System Alignment: Requirements Engineering Project

The National Ignition Facility (NIF) is the world’s largest and most energetic laser, and it is comprised of 192 laser beams that must align onto one target for the purpose of learning about Internal Confinement Fusion (ICF) and High Energy Density (HED) physics. A new NIF capability under development is the Direct Laser Impulse (DLI). The DLI capability will provide a test environment where high pulsed laser energy is delivered to a three-dimensional target. Achieving this delivery to target relies on a precision alignment and positioning of the two redirected NIF beams, as shown in Figure 1. When aligned, the two combined beams—with a frequency converted from infrared (IR) to green laser light, at a fluence (energy per unit area) of roughly 20 joules per square centimeter—will be capable of delivering up to 30 kilojoules of direct, unfocused energy to a one cubic foot target. The 40-cm x 40-cm aligned impulse area at the DLI target interaction plane (TIP) is achieved by using a beam path comprised of pickoff and transport mirrors, frequency conversion crystals, optics serving as environmental barriers, and debris shields. A separate aligned diagnostic beam path is also required for impulse to TIP characterization. Final in-situ alignment is required for the two populated diverted NIF beam paths onto the DLI target as well as the diagnostic optical beam path. Existing NIF alignment subsystems do not offer references that meet DLI’s unique demand. The new DLI Red Box, which has been designed to allow for alignment, has been shown to require deviation from the intended configuration and operational use case to obtain adequate functionality. A systems engineering evaluation has identified a solution that meets the stakeholder requirements while optimizing key performance parameters. The solution, referred to in this document as the Red Box “+” Rotated, was determined to be an improved version of the current DLI Red Box. This system offers improved system repeatability and alignment stability while maintaining similar interfaces and decreasing the demand for engineer/operator interaction.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2022

Removable, Sequestration Coatings for Mitigating Hazardous Contaminants Related to Deactivation and Decommissioning Activities

This project is a collaborative effort between InnoSense LLC (ISL) and Oak Ridge National Laboratory (ORNL) aimed at mitigating the mercury (Hg) contamination problem at the Y-12 National Security Complex (NSC). The report summarizes the research and technology development work of the Phase IIB Project, led by Dr. Uma Sampathkumaran at ISL for the period of July 31, 2017–October 31, 2021. The Y-12 site cleanup includes technologies for safe and cost-effective facility demolition, soil remediation, and on-site treatment and disposal of mercury bearing wastes. One of the technology demonstration goals was a reactive strippable coating for targeted pre-demolition and de-contamination to limit Hg mobilization and the volume of debris requiring treatment for disposal. Toward this, ISL has developed a water-based reactive strippable coating (Trap & See-Hg™) to sequester elemental Hg(0) and mercuric Hg(II) species in the coating. The coating provides multiple benefits including (1) Hg vapor suppression, (2) sealing in the hazardous contaminants, (3) visually locating the contaminant through color changes, and (4) remediating the contaminated surfaces upon coating removal. Through collaboration between ORNL and ISL in Phase II work, the team successfully demonstrated the Trap & See-Hg technology to (1) visually locate the presence of Hg on concrete, soil and drywall surfaces, (2) effectively sequester all mercury species (elemental, soluble and insoluble Hg) from lab-generated and ex-situ soil and brick/rubble samples collected from the Y 12 site with 80 to 95% efficiency to capture/reduce Hg vapor concentration, (3) be applied by manual and robotic spray applicators and cure at room ambient, (4) remain a cohesive and peelable coating upon drying, and (5) sequester Hg0 from walls in the alpha-2 building basement at Y-12 during a small scale in-situ field trial. In Phase IIB, ISL’s effort was focused on refining the coating formulations with additives containing passive and reactive sorbents, colorimetric indicator, and thixotropic agents to achieve the desired performance. The paints were then evaluated at ORNL for applicability to metal and concrete surfaces of different sizes and shapes, and soil rubble, Hg-sorption capacity and achieving sag-free coating on surfaces when applied by a manual spray applicator. Ambient cure of the coating resulted in a dry thickness of 16–20 mil. The coatings were removed from smooth or rough surfaces with low to moderate force. Both lab-generated Hg-contaminated samples and soil and brick/rubble samples containing a range of Hg concentrations (collected from the Y-12 site by UCOR) were used in this project. Optimized formulations were applied to these samples and evaluated for ability to suppress Hg vapors, sequester Hg 0 and Hg(II) species and color mapping of mercury species on the test surface. The ORNL team initially identified three to four potential sites at Y-12 and ORNL for potential demonstration. However, the pandemic closed any possible avenues for on-site demonstration of the robotic spray applicator. The metal and concrete samples with low to high Hg content provided by UCOR from an ongoing demolition were subsequently used for ex-situ sample characterization and analysis at ORNL over a period of 25 days. The coatings suppressed Hg vapors with an efficiency of 95–99% from heavily contaminated metal and 60% from concrete substrate. Analysis of total Hg in the peeled paints indicates sorption capacities ranging from 12 µg Hg/g of paint from concrete to 1.2 mg Hg/g of paint from the metal substrates while peeled paints from soil samples could capture a total Hg from 2.3 mg Hg/g to 66 mg/g paint. Toxicity characteristic leaching procedure (TCLP) tests recovered total mercury leached at 0.15±0.0008 µg/L for concrete to 126.81±0.67 µg/L and 377.25±5.67 µg/L for the two metal substrates, to allow for informed decisions on downstream disposal considerations. Together, this Phase IIB demonstrated the potential value of the Trap & See-Hg for Hg uptake, vapor suppression, and color mapping, and may thus be used to enhance worker safety during site cleanup, facility demolition, and downstream waste disposal at Y-12 NSC.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

Experimental Set-up for the Study of Chemical Fractionation and Aerosol Dynamics

Experimental investigations of chemical fractionation/phase partition and aerosol dynamics in high-temperature environment were reviewed and discussed. Particle composition and size distribution are the key data for aerosol dynamics predictive model and simulation. However, there were no particle size distribution available from the previous works. Nucleation, condensation, and coagulation are three key physical processes driving the fractionation or phase partition thereby the aerosol dynamics. A new approach was proposed to experimentally observe fractionation/phase partition and provide data for validating the predictive model for aerosol dynamics in the simulation of bomb debris formation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Nuclear Data Needs for Radiochemistry

There are many elements of interest to the weapons community that include light elements, activation products, fission products, actinides, and heavy elements. Of course, that is the whole periodic table! In this memo we summarize a down-selected list, 22 of 118+ of elements that have or could serve as radiochemical diagnostic measurements. The simulations would need cross sections for nuclides (and metastable states) of these elements to be able to calculate values for comparison with debris measurements.

36 MATERIALS SCIENCE↗
DOE OSTI2022

H-Canyon Jumper Gasket Sealing Evaluation

H-Canyon Documented Safety Analysis approved December 2019 credits the leak integrity of H-Canyon (HCA) process tanks, piping, and jumpers in preventing the release of radioactive material in a post seismic environment. Demonstration of leak tightness capability for this equipment was achieved through substantial analytical effort. However, one potential weak point that affects leak integrity exists at the gasketed joint between Hanford Connectors (HC) and nozzles. Review of the HCA Crane Log over a three-year period indicates the HCs periodically leak. Savannah River National Laboratory (SRNL) was requested to perform gasket compression tests that evaluate gasket relaxation characteristics, i.e., creep, and provide improvements to the HC installation process that can reduce or eliminate the frequency of leaks at HCs. A HC torque value of 312 ft-lbf is the target value used because it is the minimum torque value, with 95% confidence, when an unlubricated HC is impacted for standard sealing period of 9 seconds. In the HCA pipe-jumper connections are installed remotely by using HCs. HCs inherently add to the uncertainty of a gasketed joint because a calibrated torque value cannot be applied. The gasket material is a special material made of asbestos-fiber impregnated with Teflon. This material has been used for decades and generally performs well but does leak intermittently as gaskets creep and preloaded torque is lost. Gasket types are either snap-ring (SR) or lampshade (LS). Both gasket types cover the same seating area. The SR gasket is designed to remain with the jumper when the jumper is removed leaving the nozzle faces clean of any debris. SR gaskets are initially installed when the jumper is fabricated. Changing gaskets is time consuming and the radioactive environment presents risks to personnel. When jumpers are removed LS gaskets could be used to better seal the connection to reduce down time and ALARA concerns. That is, an LS gasket would be remotely positioned over the nozzle and the HC reinstalled. Testing also included two situations not typical of plant operation. One situation was the use of the non-standard double-layered gaskets (DG), and the other situation was the use of a LS without removal of the installed SR gasket. The DG was used when the supply of LS gaskets ended, so that testing could continue. It was of interest to demonstrate this gasket’s creep response because the DG, which was two gaskets glued together, was thicker than the LS gasket and the thicker material was expected to elicit a greater creep characteristics. The second situation of using two gaskets together by installing an LS gasket without removing the installed gasket is not allowed by the ASME Codes. However, by demonstrating the creep history of such a gasket arrangement it could be considered as an option that could possibly seal a connection while significantly reducing operational down time and personnel risk. Forty tests were conducted, and the overall results demonstrate the initial applied force and how the gasket changes with time. The change in sealing force, in terms of torque, was then measured to obtain a force history as the gaskets creep. This report documents the results of those tests as well as the method used to perform the tests.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2023

U.S. Efforts in Support of Examinations at Fukushima Daiichi - November 2022 Meeting Notes and Information Request Status

Information obtained from Fukushima Daiichi Nuclear Power Station (Daiichi) is required to inform future Decontamination and Decommissioning (D&D) activities, improving the ability of the Tokyo Electric Power Company Holdings, Incorporated (TEPCO Holdings) to characterize potential hazards and to ensure the safety of workers involved with cleanup activities. This information also has important implications for the safety and operation of U.S. commercial nuclear power plants. This document summarizes results from the Fiscal Year 2023 (FY2023) U.S. effort to review Daiichi information and extract insights to enhance the safety of existing and future nuclear power plant designs. This U.S. effort, which was initiated in 2014 by the Department of Energy Office of Nuclear Energy, is completed by a group of experts in reactor safety and plant operations that identify examination needs and evaluate recent Daiichi examination data to address these needs. Fukushima-related information and associated discussions during these meetings benefit operating, new, and advanced reactors. Significant safety insights have been and are continuing to be obtained in several areas: system and component performance, radionuclide surveys and sampling, debris end-state location, combustible gas effects, and plant operations and maintenance. In addition to reducing uncertainties related to severe accident modeling progression, these insights have and continue to be used to update guidance for severe accident prevention, mitigation, and emergency planning. Furthermore, Daiichi-related activities, such as code modeling improvements and analysis, testing, and new technology deployment efforts, have the potential to offer additional benefits to the operating fleet and new LWR and non-LWR designs. U.S. evaluations of obtained examination information and input regarding future Daiichi examinations are of interest to several organizations within Japan. Since its inception, the U.S. has provided consensus input for high priority time-sequenced examination tasks and supporting research activities. In their Mid-to-Long-term Examination Plan for 1F investigations, TEPCO included all remaining U.S. consensus information requests and additional information requests they identified. TEPCO periodically provides reports on the status of these requests (reflecting D&D priorities, new insights from investigations, and new technologies that become available). Hence, U.S. experts agreed that it was appropriate for TEPCO to track and prioritize these information requests as D&D progresses. U.S. experts will continue to review and comment on the information obtained from examinations and, as needed, provide additional details and relevant background material to support future examinations. As documented in this report, several other items, such as additional details on information requests pertaining to ex-vessel examinations, relevant references from prior research, additional documents to provide insights regarding recent investigation findings, and reviews of recently released documents, were agreed to during the FY2023 meeting.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2021

Record of Technical Change for Addendum to the Closure Report for Corrective Action Unit 113: Area 25 R-MAD Facility, Nevada National Security Site, Nevada

This addendum to the Closure Report for Corrective Action Unit 113: Area 25, Reactor Maintenance, Assembly, and Disassembly Facility, Building 3110, Nevada Test Site, Nevada, DOE/NV--891-VOL I-Rev. 1, dated July 2003, provides details of demolition, waste disposal, and use restriction (UR) modification for Corrective Action Unit 113, Area 25 R-MAD Facility. Demolition was completed on July 15, 2010, when the last of the building debris was disposed. Final field activities were concluded on August 30, 2010, after all equipment was demobilized and UR signs were posted. This work was funded by the American Recovery and Reinvestment Act.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Riverine Plastic Pollution: Field Sampling Protocol and Implementation in U.S. Rivers

Riverine plastic pollution is increasingly being recognized as a serious environmental concern. The flux of plastic from U.S. rivers into the oceans is estimated to be on the order of hundreds of tons per year. Plastic pollution has been detected in all major U.S. rivers but the observations did not measure metrics that could be used for mass flux calculations. The Department of Energy is addressing the problem of riverine plastic pollution with the Waterborne Plastics Resource Assessment and Debris Characterization (WaterPACT) project. Phase one of the WaterPACT project includes the development of a sampling protocol, field sampling events that implement the protocol, and numerical modeling studies. The field sampling will quantify and characterize the plastic pollution and the numerical modeling studies will analyze the movement of the plastic pollution by rivers. This report details the WaterPACT sampling protocol and its implementation in four major U.S. rivers. The WaterPACT sampling protocol was implemented in the Mississippi, Columbia, Delaware, and Los Angeles rivers with at least three sampling events in each river. The rivers represent four types ranging from the large Mississippi with its vast agricultural watershed to the small Los Angeles with its highly engineered urban waterway. The three sampling events covered a variety of discharge conditions from low drought flow to extreme storm events. The data obtained by the WaterPACT sampling of the four rivers will be combined to provide an invaluable dataset to researchers studying the source and chemical composition of plastic pollution and modelers estimating the flux of plastic being transported to and released into the oceans.

13 HYDRO ENERGY↗