Bottom water suspended particulate matter (SPM) concentration (mg/L) at 1 m above the seafloor and successive distances (50 m to 1800 m) from the mining collector impact site in the Belgian-sponsored (GSR) contract area in the Clarion Clipperton Zone during the MANGAN 2021 (IP21) expedition. The data are from 16 optical backscatter sensors mounted on different benthic seafloor platforms (please see Vink et al. 2022 and Gazis et al. 2025). The sensors used are: stand-alone JFE Advantech Infinity Series ATUD-USB (JFE), stand-alone AQUAlogger® 310TY (Aqualogger), WetLabs ECO FLNTU (FLNTU) coupled on SBE16 and SBE19+ CTDs and Seapoint STM-S (Seapoint) coupled on SBE19+ CTDs. The JFE, FLNTU and Seapoint data are averaged to 5-minute intervals. The Aqualogger are averaged to 2-minute intervals. The acquisition settings are described in Vink et al. (2022), and the data processing and calibration to SPM concentration are described in Gazis et al. (2025). GEOMAR Helmholtz Centre for Ocean Research Kiel (GMR), Royal Netherlands Institute for Sea Research (NIOZ), Royal Belgian Institute of Natural Sciences (RBINS) and Jacobs University Bremen (JUB; now Constructor University) provided the sensors in the framework of the JPIO MiningImpact2 project.