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Sediment Pond
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Sediment carried by rainfall is one of the greatest
potential environmental hazards of surface mining. Under the Surface
Mining Law ALL surface water flowing off disturbed areas of the mine
must be routed through sediment ponds. The ponds are designed to slow
the flow of water |
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Riprap
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One of the most commonly used erosion control
practices found in mine reclamation, highway construction, and
throughout the construction industry is rock riprap. Here at this
Southern Indiana reclaimed mine site riprap is used in the emergency
overflow of a permanent pond. If high rainfall occurs and more water
flows into the pond than the drain can handle, the excess will flow
safely over the riprap without causing erosion. This rock lining of the
drainage channel slows the flowing water and prevents erosion of the
soil under the rock.
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Jute Matting
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At this North Dakota mine reclamation site, a natural
drainage swale is lined with a jute mat to prevent erosion until the
grass becomes established. This is an erosion control practice that has
been used successfully for many years on farms all across the country
and is now commonly used in mine reclamation. This is a short-term
erosion control practice that is a safeguard in areas prone to flash
flooding or where it takes a long time to establish a dense grass cover.
The matting is placed over the prepared seedbed and "stapled"
to the ground to prevent it from washing down the slope. The mat holds
the soil in place and provides cover for the new grass seedlings as they
become established. |
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Concrete Drainage Channel
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At this reclaimed abandoned mine project, water flows
continuously down the channel to a stream at the bottom of the hill.
Because the continuous flow of water and steep grade would damage a less
resistant erosion control practice, a specialized mat was set in the
graded channel and filled with concrete. When the concrete dried it
formed a permanent channel for the water to flow. Although more
expensive than a grass or riprap water way, this practice provides
long-term erosion control for the fast moving water that drains off this
reclaimed land.
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Rock-lined Drain
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Large rock-lined drains have become one of the most
commonly used methods of channeling water down steep hillsides at mine
sites. Here on this Kentucky mine reclamation site, the operator has
carefully set flat rock on the bottom and sides of the water channel. As
one mine inspector said "if rock drains at all mines were
constructed like these we would eliminate almost all chance of erosion
occurring where collected water was drained from the reclamation
site." This rock-lined drain carries water down the steep hill and
into a pond at the bottom. Its wide (7- to 8-foot) flat bottom can carry
large flows of water and will continue to function many years after the
reclamation bond has been released. |
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Erosion Control Structures
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To prevent soil erosion during periods of heavy
rainfall and high stream flow, two concrete structures are constructed.
The concrete structures allow rapidly flowing water to drop in elevation
without causing erosion of the creek bed. At the bottom of the structure
concrete blocks are constructed to slow the flow of water and dissipate
the force of the water. These structures provide a permanent solution to
erosion control of the stream bed and provide a stable hydrologic
environment that will remain for many years.
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The Mine Site Today
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Today, after reclamation, the stream channel
in this rural Texas landscape remains functional, aesthetically
pleasing, and an important part of the natural environment. The
successful mine reclamation has resulted in a productive environment
that is difficult to distinguish from the surrounding unmined landscape. |
