Influence Modeling of muddy phosphate mining waste discharge on hydrodynamics in the Beninese-Togolese coastal waters and transport of waste phases

Influence Modeling of muddy phosphate mining waste discharge on hydrodynamics in the Beninese-Togolese coastal waters and transport of waste phases | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Influence Modeling of muddy phosphate mining waste discharge on hydrodynamics in the Beninese-Togolese coastal waters and transport of waste phases Daouda SAMA, M’bènibé GMAKOUBA, Pamane KPIAGOU, Lipoublida DJAGRE, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6298265/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The Kpémé plant (Togo) discharges phosphate-rich muddy waste laden with heavy metals (Cr, Cd, Hg, etc.) into the coastal ocean. These discharges, composed of heavy apatite-rich phases and light clay-rich phases, disrupt hydrodynamics, degrade water quality, contaminate ecosystems, and threaten human health via bioaccumulation. This study employs the Delft3D suite (FLOW, WAVE) to model the transport of waste phases (density, particle size) and their impacts along the Beninese-Togolese coastline. Simulations integrate bathymetric data (GEBCO), meteorological inputs (ERA5), in situ measurements, and span two key seasons (May and August 2024) to predict dispersion, sedimentation, and ecological risks. The assessed extended seasons revealed distinct hydrological contrasts along the Beninese-Togolese coast. Current velocities and wind-driven wave heights were higher during the cold season (depth-averaged velocities up to 0.272 m/s; significant wave heights up to 0.70 m), promoting enhanced dispersion of light clay-rich phases toward deeper waters. Sediment transport increased during the cold season, with average depth flow rates rising by + 76.77 m³/s compared to the warm season. Heavy apatite-rich phases accumulated nearshore (0.97–305.90 m³/s), particularly along Togolese coastal zones, while light clay-rich phases migrated toward oceanic depths (0.61–39.28 m³/s), forming extensive turbid plumes. Sediment transport elevated turbidity, degraded benthic habitats, and dispersed heavy metals. Seasonal dispersion of waste phases was amplified during the cold season. Heavy apatite-rich phases predominantly impacted coastal zones, whereas light clay-rich phases contaminated deep-sea ecosystems. This modeling underscores the urgent need for mitigation strategies (e.g., waste pretreatment, monitoring) to safeguard biodiversity and public health. Phosphate sludge waste Coastal hydrodynamics Delft3D modeling Sediment transport Heavy metals Full Text Additional Declarations No competing interests reported. Supplementary Files ESM1.docx ESM2.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6298265","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":450479588,"identity":"1203eabf-f234-4403-9d4f-a4556378b81b","order_by":0,"name":"Daouda 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These discharges, composed of heavy apatite-rich phases and light clay-rich phases, disrupt hydrodynamics, degrade water quality, contaminate ecosystems, and threaten human health via bioaccumulation. This study employs the Delft3D suite (FLOW, WAVE) to model the transport of waste phases (density, particle size) and their impacts along the Beninese-Togolese coastline. Simulations integrate bathymetric data (GEBCO), meteorological inputs (ERA5), in situ measurements, and span two key seasons (May and August 2024) to predict dispersion, sedimentation, and ecological risks. The assessed extended seasons revealed distinct hydrological contrasts along the Beninese-Togolese coast. Current velocities and wind-driven wave heights were higher during the cold season (depth-averaged velocities up to 0.272 m/s; significant wave heights up to 0.70 m), promoting enhanced dispersion of light clay-rich phases toward deeper waters. Sediment transport increased during the cold season, with average depth flow rates rising by +\u0026thinsp;76.77 m\u0026sup3;/s compared to the warm season. Heavy apatite-rich phases accumulated nearshore (0.97\u0026ndash;305.90 m\u0026sup3;/s), particularly along Togolese coastal zones, while light clay-rich phases migrated toward oceanic depths (0.61\u0026ndash;39.28 m\u0026sup3;/s), forming extensive turbid plumes. Sediment transport elevated turbidity, degraded benthic habitats, and dispersed heavy metals. Seasonal dispersion of waste phases was amplified during the cold season. Heavy apatite-rich phases predominantly impacted coastal zones, whereas light clay-rich phases contaminated deep-sea ecosystems. This modeling underscores the urgent need for mitigation strategies (e.g., waste pretreatment, monitoring) to safeguard biodiversity and public health.\u003c/p\u003e","manuscriptTitle":"Influence Modeling of muddy phosphate mining waste discharge on hydrodynamics in the Beninese-Togolese coastal waters and transport of waste phases","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-02 09:19:29","doi":"10.21203/rs.3.rs-6298265/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"414fdca9-b0d0-4599-a6af-62e2465ddb73","owner":[],"postedDate":"May 2nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-07-03T06:08:44+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-02 09:19:29","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6298265","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6298265","identity":"rs-6298265","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}