During the process of secondary grading, small depressions may be established on an opportunistic basis. These features will enhance post-mining topographic diversity and act as seasonal surface water collection sites. Small depressions will serve as wildlife enhancement features and micro-topographic niches for establishment of music and/or hydria plant species. Although these depressions will not have specific design criteria, they will be small enough that they will occur within the limits of the approved AOC. These small depressions will also meet the following specific criteria:

•  Each depression or combination of directly adjacent depressions will be less than one acre foot total capacity,
• No depression will be deeper than 10 feet,
• All small depressions will be incised (below ground level),
• The maximum in slope for the small depression will be 6:1 and
• At bond release, small depression areas will be subject to vegetation sampling similar to any area within the bond release parcel.

Back to Small Depressions Guidance Introduction

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2/6/01