Evaluation of Strength Properties of Bio-remediated Crude Oil Contaminated Soil using Bacillus pumilus for Use as Liner and Cover Material in Municipal Solid Waste Containment Applications

Evaluation of Strength Properties of Bio-remediated Crude Oil Contaminated Soil using Bacillus pumilus for Use as Liner and Cover Material in Municipal Solid Waste Containment Applications | 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 Evaluation of Strength Properties of Bio-remediated Crude Oil Contaminated Soil using Bacillus pumilus for Use as Liner and Cover Material in Municipal Solid Waste Containment Applications Hinafulo Simon Joel, Thomas Stephen Ijimdiya, Kolawole Juwonlo Osinubi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8755825/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 15 You are reading this latest preprint version Abstract This study evaluates the effectiveness of Bacillus pumilus -induced calcite precipitate to enhance the engineering performance of bio-remediated crude oil-contaminated soils for waste containment applications. Remediated soil samples were bio-treated with Bacillus pumilus (B) – cementation reagent (C) mixtures. Trial mix ratios of 75% B – 25% C, 50% B – 50% C, and 25% B – 75% C with B. pumilus suspension densities in the range 1.5 × 10⁸ − 2.4 × 10⁹ cells/ml and a fixed cementation reagent concentration. The 50% B – 50% C ratio yielded optimum improvement and was adopted in this study. The cementation reagent was prepared and applied to soil samples compacted using three energy levels namely, British Standard light (BSL), West African Standard (WAS), and British Standard heavy (BSH). The bio-cementation with B. pumilus (1.5 × 10⁸ to 2.4 × 10⁹ cells/ml) cementation solutions under gravity infiltration on the post-remediated soil specimens showed slight improvements with liquid limit reducing from 43.8% to 41.1%, plastic limit increased from 36.3% to 37.5%, and the plasticity index increased from 7.3% to 7.4%. UCS values reached 225.4, 264.4, and 385.1 kN/m² for BSL, WAS, and BSH compaction, respectively, recorded exceeded the minimum requirement of 200 kN/m². The findings confirm that bio-cementation using B. pumilus can effectively enhance the strength and plasticity characteristics of bioremediated oil-contaminated soils, supporting their suitability as liner and cover materials in waste containment systems. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 26 Mar, 2026 Reviews received at journal 15 Mar, 2026 Reviews received at journal 14 Mar, 2026 Reviewers agreed at journal 10 Mar, 2026 Reviews received at journal 10 Mar, 2026 Reviews received at journal 10 Mar, 2026 Reviewers agreed at journal 06 Mar, 2026 Reviewers agreed at journal 06 Mar, 2026 Reviewers agreed at journal 06 Mar, 2026 Reviewers agreed at journal 05 Mar, 2026 Reviewers invited by journal 05 Mar, 2026 Editor invited by journal 24 Feb, 2026 Editor assigned by journal 20 Feb, 2026 Submission checks completed at journal 19 Feb, 2026 First submitted to journal 19 Feb, 2026 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-8755825","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":603797260,"identity":"8a442991-6b11-41ff-9cd1-cb10bb18ba38","order_by":0,"name":"Hinafulo Simon Joel","email":"","orcid":"","institution":"Ahmadu Bello University","correspondingAuthor":false,"prefix":"","firstName":"Hinafulo","middleName":"Simon","lastName":"Joel","suffix":""},{"id":603797264,"identity":"78da487f-9210-4715-9632-1ed371a2ad5e","order_by":1,"name":"Thomas Stephen Ijimdiya","email":"","orcid":"","institution":"Ahmadu Bello University","correspondingAuthor":false,"prefix":"","firstName":"Thomas","middleName":"Stephen","lastName":"Ijimdiya","suffix":""},{"id":603797266,"identity":"3543fc45-581b-4e98-8882-2d6ea3ba8e39","order_by":2,"name":"Kolawole Juwonlo Osinubi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA60lEQVRIiWNgGAWjYBACCYYDDAwJQMTG3sAGEmBsIF4LzwGitUBAAoNEApFaJBsPH/7wcMfhPD7Jx88e8zDYyG44wHv4BT4t0gzH0iQSzxwuZpNOMzfmYUgz3nCAL80CnxY5hjNmDIlthxPbpBPMpHkYDiduOMBjZkBAi/EHsBbJ49+AWv4T1iLNcMZAAqxFggdkywGQFuMH+LRINoD80pZezMaTU244xyDZeOZhHjN8Ohgkbhw+/PFnm3WefPvxbQ/eVNjJ9h3vMf6AX88BZB7IE8wMbBLY1UIBfwOmGDN+W0bBKBgFo2CkAQALmkvkFvpLfQAAAABJRU5ErkJggg==","orcid":"","institution":"Ahmadu Bello University","correspondingAuthor":true,"prefix":"","firstName":"Kolawole","middleName":"Juwonlo","lastName":"Osinubi","suffix":""}],"badges":[],"createdAt":"2026-02-01 11:39:33","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8755825/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8755825/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104441411,"identity":"1529ff3f-2f90-465c-8c7a-825335691952","added_by":"auto","created_at":"2026-03-11 18:25:06","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":656773,"visible":true,"origin":"","legend":"","description":"","filename":"HINAFULOJ.RevisedPaper21392025ITS20NOV25R130DEC25611.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8755825/v1_covered_521f52f6-7340-4aa3-8d86-9bb8dd28ce17.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Evaluation of Strength Properties of Bio-remediated Crude Oil Contaminated Soil using Bacillus pumilus for Use as Liner and Cover Material in Municipal Solid Waste Containment Applications","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"discover-soil","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Soil](https://link.springer.com/journal/44378)","snPcode":"44378","submissionUrl":"https://submission.nature.com/new-submission/44378/3","title":"Discover Soil","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8755825/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8755825/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study evaluates the effectiveness of Bacillus \u003cem\u003epumilus\u003c/em\u003e-induced calcite precipitate to enhance the engineering performance of bio-remediated crude oil-contaminated soils for waste containment applications. Remediated soil samples were bio-treated with Bacillus \u003cem\u003epumilus\u003c/em\u003e (B) \u0026ndash; cementation reagent (C) mixtures. Trial mix ratios of 75% B \u0026ndash; 25% C, 50% B \u0026ndash; 50% C, and 25% B \u0026ndash; 75% C with B. \u003cem\u003epumilus\u003c/em\u003e suspension densities in the range 1.5 \u0026times; 10⁸ \u0026minus;\u0026thinsp;2.4 \u0026times; 10⁹ cells/ml and a fixed cementation reagent concentration. The 50% B \u0026ndash; 50% C ratio yielded optimum improvement and was adopted in this study. The cementation reagent was prepared and applied to soil samples compacted using three energy levels namely, British Standard light (BSL), West African Standard (WAS), and British Standard heavy (BSH). 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The findings confirm that bio-cementation using B. \u003cem\u003epumilus\u003c/em\u003e can effectively enhance the strength and plasticity characteristics of bioremediated oil-contaminated soils, supporting their suitability as liner and cover materials in waste containment systems.\u003c/p\u003e","manuscriptTitle":"Evaluation of Strength Properties of Bio-remediated Crude Oil Contaminated Soil using Bacillus pumilus for Use as Liner and Cover Material in Municipal Solid Waste Containment Applications","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-11 18:24:52","doi":"10.21203/rs.3.rs-8755825/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-26T11:55:15+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-15T06:18:03+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-15T02:28:42+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"7584271913868917347602811049702864270","date":"2026-03-11T00:19:59+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-10T12:21:27+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-10T04:59:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"90812389904457833847923312101558367704","date":"2026-03-06T09:07:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"304894284786653077478108805588134603538","date":"2026-03-06T06:19:27+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"58851414324451270525675431778606644682","date":"2026-03-06T05:42:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"312605438416254739278933916648761775942","date":"2026-03-05T16:23:32+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-05T16:12:26+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-02-24T07:01:46+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-20T09:55:28+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-19T15:18:17+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Soil","date":"2026-02-19T12:34:11+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-soil","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Soil](https://link.springer.com/journal/44378)","snPcode":"44378","submissionUrl":"https://submission.nature.com/new-submission/44378/3","title":"Discover Soil","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4194a234-4bb5-4a5b-a590-5c9e024b18a7","owner":[],"postedDate":"March 11th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-12T15:54:40+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-11 18:24:52","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8755825","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8755825","identity":"rs-8755825","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}