Assessment of the Transportation of Abandoned Mine Water Contaminants to the Surrounding Aquifers. A Case of Mlolongo Open-Pit Lake, Kenya

Assessment of the Transportation of Abandoned Mine Water Contaminants to the Surrounding Aquifers. A Case of Mlolongo Open-Pit Lake, Kenya | 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 Assessment of the Transportation of Abandoned Mine Water Contaminants to the Surrounding Aquifers. A Case of Mlolongo Open-Pit Lake, Kenya Ronnice Chepkoech, Bernard Ouma Alunda, Antony Mutua Nzioka This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5912174/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 27 Oct, 2025 Read the published version in Discover Water → Version 1 posted 14 You are reading this latest preprint version Abstract This study investigated the water quality of Open-pit Lake and the potential transportation of contaminants to the surrounding aquifers over time. The objectives included determining key water quality parameters, and modelling contaminants' spatial distribution and migration to understand their impact on the surrounding aquifers. Among the measured chemical water quality parameters, calcium (Ca), potassium(K), aluminium (Al), sulphates (SO₄ ²⁻ ), chlorides (Cl ⁻ ), nitrite (NO₂ ⁻ ), nitrate (NO₃ ⁻ ), and nitrogen (N) were within WHO threshold recommended limits. However, sodium (Na), ammonia (NH₄ ⁺ ), manganese (Mn), fluoride (F ⁻ ), carbonates (CO ₃ 2⁻ ), iron (Fe), and phosphates (PO 4 3− ) exceed WHO recommended threshold limits. The potential migration and transportation of contaminants were then modelled using MODFLOW and MT3DMS codes. The hydrological, geological, and concentration of contaminants were used as input parameters for the Processing MODFLOW Pro and MT3DMS models. The spatial distribution and travel distance of the selected three contaminants; sodium (Na), carbonates (CO ₃ 2⁻ ), and nitrate (NO₃ ⁻ ) from Mlolongo Open-pit Lake to the surrounding aquifers was simulated. The findings show that the spatial distribution and travel distance increase with time, with shallow aquifers being more vulnerable than deeper aquifers. In addition, the projection of the concentration of contaminants in the surrounding aquifers shows that the concentration of the contaminant increases with time and stabilizes after some time due to dilution and increased travel time. The Processing MODFLOW Pro validation results show a Mean Root Squared Error (RMSE) of 0.2240, indicating a minimal difference between the modelling results and the actual observed values, and thus, a lower modelling error. open-pit lake water quality transportation of contaminants aquifers Full Text Additional Declarations No competing interests reported. Supplementary Files Supplementary.docx Cite Share Download PDF Status: Published Journal Publication published 27 Oct, 2025 Read the published version in Discover Water → Version 1 posted Editorial decision: Revision requested 03 Mar, 2025 Reviewers agreed at journal 02 Mar, 2025 Reviews received at journal 01 Mar, 2025 Reviewers agreed at journal 28 Feb, 2025 Reviewers agreed at journal 28 Feb, 2025 Reviews received at journal 27 Feb, 2025 Reviewers agreed at journal 24 Feb, 2025 Reviewers agreed at journal 21 Feb, 2025 Reviewers agreed at journal 20 Feb, 2025 Reviewers invited by journal 14 Feb, 2025 Editor invited by journal 14 Feb, 2025 Editor assigned by journal 14 Feb, 2025 Submission checks completed at journal 13 Feb, 2025 First submitted to journal 27 Jan, 2025 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. 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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-5912174","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":416012050,"identity":"4d72d642-6e8a-4e4c-a9dd-ae1e3ec45091","order_by":0,"name":"Ronnice Chepkoech","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABF0lEQVRIiWNgGAWjYDACCQYGxgYgbQDmAUk2/uYDIHEZ4rXwSRxLAInzEKkFCOQYcsBsnFr4ZzcfezijwkbeXPrwsccFBXZybAxnPr+6UWPBw8B++OgGbJbcOZZuuOFMmuHOvrR04xkGycZszL3brHOOAR3Gk5Z2A4sWA4kcM8mHbYcTDM7wmEnzGBxIbGM4u804hw2oRYLHDLuW/G9ALf/hWurbGHKeGef8w6clh01yY9sBuJYENoYc5se5bbi1SNxIMzeccSYZ6B+2NKCWZMM2iWNmzLl9EjxsOPzCPyP52cOeCjt5gzPMx6R5/tjJy/c3P/6c861Ojp/98DFsWoCADVNEArs4Hi3MH3CrHgWjYBSMghEIAJL1XNcTDNw2AAAAAElFTkSuQmCC","orcid":"","institution":"Taita Taveta University","correspondingAuthor":true,"prefix":"","firstName":"Ronnice","middleName":"","lastName":"Chepkoech","suffix":""},{"id":416012053,"identity":"9cb2dfe7-8eb1-471f-b2c7-6ba75983ac94","order_by":1,"name":"Bernard Ouma Alunda","email":"","orcid":"","institution":"Taita Taveta University","correspondingAuthor":false,"prefix":"","firstName":"Bernard","middleName":"Ouma","lastName":"Alunda","suffix":""},{"id":416012055,"identity":"8ced4ee0-befd-41ab-9d99-02f9aa485cab","order_by":2,"name":"Antony Mutua Nzioka","email":"","orcid":"","institution":"Samgen Project Korea Branch","correspondingAuthor":false,"prefix":"","firstName":"Antony","middleName":"Mutua","lastName":"Nzioka","suffix":""}],"badges":[],"createdAt":"2025-01-27 12:23:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5912174/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5912174/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s43832-025-00278-y","type":"published","date":"2025-10-27T15:57:14+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":95039915,"identity":"877bbde1-5ed6-4aee-9b88-f469d0259b69","added_by":"auto","created_at":"2025-11-03 16:05:40","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1085225,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscriptwithtablesandfigures.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5912174/v1_covered_5347b0b9-2d08-4bea-908b-17d7293cbd31.pdf"},{"id":76419451,"identity":"61d492b4-d4a5-44e3-a2ac-524d910d759d","added_by":"auto","created_at":"2025-02-17 03:43:42","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":17255,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementary.docx","url":"https://assets-eu.researchsquare.com/files/rs-5912174/v1/d481f7879ecb92a0ad5c9e6e.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Assessment of the Transportation of Abandoned Mine Water Contaminants to the Surrounding Aquifers. 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