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Microplastics (MPs, size ≤ 5 mm) have emerged as a significant worldwide concern, threatening marine and freshwater ecosystems, and the lack of MP detection technologies is notable. The main goal of this research is the development of a camera sensor for the detection of MPs and measuring their size and velocity while in motion. This study introduces a novel methodology involving computer vision and artificial intelligence (AI) for the detection of MPs. Three different camera systems, including fixed-focus 2D and autofocus (2D and 3D), were implemented and compared. A YOLOv5-based object detection model was used to detect MPs in the captured image. DeepSORT was then implemented for tracking MPs through consecutive images. In real-time testing in a laboratory flume setting, the precision in MP counting was found to be 97%, and during field testing in a local river, the precision was 96%. This study provides foundational insights into utilizing AI for detecting MPs in different environmental settings, contributing to more effective efforts and strategies for managing and mitigating MP pollution. [ABSTRACT FROM AUTHOR]

The accumulation of significant amounts of investigation‐derived waste (IDW) from investigations of per‐ and polyfluoroalkyl substances (PFAS) contamination at active and former military installations has generated the need for viable disposal methods, which are currently limited to incineration or landfilling. Soil washing has been proposed as a more environmentally friendly alternative method to remove PFAS sorbed to IDW media, potentially allowing more cost‐effective disposal of the media as nonhazardous waste. This systematic investigation of IDW washing explored the effect of water‐, methanol‐, and salt‐based solutions, which are typically used for ion exchange (IX) resin regeneration. These solutions were tested for PFAS removal using four different field IDW solids with different pHs, total organic carbon content, and anion exchange capacity. In long washes extending to a week, distilled water was found to be effective in the removal of short‐chain PFASs (perfluorcarboxylic acids with fewer than seven fluorinated carbon atoms and perfluorosulfonic acids with fewer than six fluorinated carbon atoms) and some long‐chain PFASs including perfluorooctanoic acid, but not perfluorooctane sulfonic acid (PFOS). PFOS was only removed using water:methanol solutions with salt. Optimized 30‐min washes containing water:methanol and salt effectively removed precursors, and short‐ and long‐chain PFAS. Kinetic, soil extraction, and leaching experiments revealed that PFAS can be removed within a matter of minutes, with greater than 70% PFAS removal on the first wash; however, longer‐chain PFASs required up to three washes to be removed. Important IDW wash solution relationships influencing PFAS desorption are discussed and PFOS is proposed as an indicator species for IDW washing effectiveness. Results demonstrate that adapting components of IX regeneration solutions to IDW wash solutions facilitates an alternative means to separate PFAS contaminants from IDW, advancing PFAS remediation efforts. [ABSTRACT FROM AUTHOR]