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Basic Technical IVT Commonly tested

Capping Layer

noun

Pronunciation: /ˈkæpɪŋ ˈleɪər/

A protective barrier material placed over contaminated or exposed mine waste to prevent water infiltration, oxidation, and contaminant leaching. Common capping materials include compacted clay, synthetic liners, and composite soil covers.

Plain English

A protective covering placed over mine waste to prevent water from carrying pollutants into the ground.

Etymology & History

Origin languageEnglish
RootCap from Middle English 'cappe' + layer from Old English 'leger'
First recorded use1980s
Usage frequencyVery common

Usage

"Engineers installed a two-meter capping layer of compacted clay over the tailings to minimize acid generation."

Style guide notes: Avoid hyphenating; write as two words unless used as adjective 'capping-layer design'.

Also known as

cap system cover system waste cover

Contrasted with

exposed surface uncovered waste

Related Terms

Frequently Asked Questions

What materials are used for mine capping layers?

Clay, geotextiles, synthetic liners, soil amendments, and compost form effective multi-layered cap systems.

Why is capping necessary in mine reclamation?

Caps isolate waste from oxygen and water, preventing chemical reactions that generate acidity and dissolve contaminants.

Why Test Candidates on This?

Essential for evaluating containment strategies and understanding multi-barrier approaches in environmental remediation.

Required skill level: Mid

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