Approximate Original Contour
phrasePronunciation: /əˈprɑksəmət əˈrɪdʒənəl ˈkɑntur/
Also written as: AOC — Approximate Original Contour
A reclamation standard requiring the restoration of mined land to surface configurations that closely resemble the pre-mining topography.
Full Definition
Approximate original contour is a fundamental principle in surface mine reclamation that mandates the restoration of disturbed areas to topographic configurations that approximate the natural landscape that existed before mining activities. This standard requires careful documentation of pre-mining conditions and engineering design to recreate landforms that support natural drainage patterns, minimize erosion, and provide suitable conditions for establishing the planned post-mining land use. The approximate original contour standard balances the practical limitations of earthmoving operations with the environmental goal of landscape restoration. Compliance with this requirement is typically demonstrated through detailed topographic surveys and engineering plans.
Plain English
A rule that says after mining is done, the land has to be put back to look pretty much like it did before the mining started.
In Editorial Context
A fundamental reclamation principle often used to evaluate the thoroughness and quality of restoration efforts, representing the regulatory commitment to landscape restoration.
Etymology & History
Established by the Surface Mining Control and Reclamation Act as a key reclamation performance standard
Originally applied strictly but interpretations have evolved to accommodate practical engineering limitations
Usage
"The editorial criticized the mining company's AOC variance request as undermining the intent of comprehensive landscape restoration."
Usage note: Commonly abbreviated as AOC in technical documents but should be spelled out for general audiences
Context: reclamation regulations, permit applications, compliance monitoring, environmental impact assessments
Region: US
Style guide notes: Always capitalize all three words when referring to regulatory standard; abbreviate as AOC only after first use; Chicago Manual requires full spelling in formal documents
In Context
- "The reclamation plan must demonstrate restoration to approximate original contour within acceptable variance limits."
- "Regulators granted a variance from approximate original contour requirements to create a beneficial water impoundment."
- "Achieving approximate original contour while improving drainage patterns requires careful engineering design."
Also known as
Contrasted with
Don't confuse with
AOC allows for reasonable approximation while exact restoration is rarely achievable or required
Common mistake: Interpreting as exact restoration rather than approximate; confusion about variance allowances; not understanding exceptions for improved land use
Related Terms
Broader term: Topographic Restoration
Frequently Asked Questions
What does 'approximate' mean in Approximate Original Contour standards?
Approximate allows for reasonable variations from exact pre-mining elevations while maintaining overall topographic character and drainage patterns of the original landscape.
When can mining operations receive variances from AOC requirements?
Variances may be granted when alternative configurations provide equal or better utility, are technically and economically feasible, and provide enhanced environmental benefits.
How is compliance with AOC requirements measured and verified?
Compliance is verified through topographic surveys comparing final contours to approved reclamation plans and pre-mining topographic data within specified tolerance ranges.
Why Test Candidates on This?
Essential regulatory concept that determines acceptable restoration standards and distinguishes between different reclamation approaches
Required skill level: Mid