Top soil minimum- 2 inches

Sodding soil minimum- 4 inches

What is a debris basin?

Why would it be needed?

Debris basin- place where runoff leaves the site

Needed if large construction projects expose a lot of bare soil and provisions need to be made to catch the sediement produced

Reduce road gradients- usually makes steep banks

Bridges, culverts and other waterway structures

Soild foundation and adequate drainage

Vegetation

Easy to establish, and erosion resistant

not grow tall enough to obstruct vision

If terracing is implemented, then have plants with deep roots

1. Surface mining- removes soil/rock that covers the deposit, one strip at a time, and deposits soils from current mining area to the previous strip section

2. Shaft mining- digging vertical shaft from above the deposit to the surface. Beams supporting may rot over time and cause a collapse

How do spoils become highly acidic?

How is this treated?

Spoils from coal mines often make lots of sulfuric acids when they are oxidized. Makes soil pH 2 or 3 which can pollute the local water source and surrounding soil.

Easiest- bury the sulfides deep enough to keep them anaerobic.

More expensive- add enough lime to neutralize soil to keep it from killing other plants and animals

1. Coal- 41%

2. Sand and gravel- 26%

Stone- 8%

In alluvial deposits on valley floors or in terraces

But some result from glacial deposits

Why are metal deposits associated with foothills and mountains?

What did the PL 95-87, surface and mining control and reclaimation act specify?

That restoration processes begin within 10 years after surface mining has ceased.

Runoff must be controlled during mining operation to keep toxins and sediment out of water sources

(usually requires a sediment pond)

1. compaction from equipment and traffic

2. piles created on near by surfaces

3. eroded areas that are unprotected can be affected by the wind, causing sandblasting, and continue to expand the eroded area until measures are taken

1. cover the soil 1 meter with non compacted soil (mine soil). It doesnt have organic matter, so it might have compaction and crusting problems

2. use spoils material and add organic matter/plant residue/manure, compost/peat, and loosen compacted layers with a chisle.

3. add sewage sludge into mine spoils, but must be mixed

What 5 steps are needed to reclaim a gully?

1. Divert the water away from the head to the gully to a safe disposal area (diversion can be removed after gully is stablized)
2. head and sides of gully need to be smoothed
3. channel slope should be smoothed to .05% max
4. establish a grassed waterway in the area that will carry the water- wide enough to carry the largest flow
5. fence area to exclude animals until vegetation is well established

Describe a grassed/vegetated waterway

When are they used?

nautal or constructed drainageways that are thick with grass cover. Some are constantly too wet for grasses and stone lining needs to be installed

tough to resist runoff erosion and tolerate submergence

Used to prevent gully formation or outlets for terraces or diversions

v-shaped, parabolic and trapezoidal

designed to carry most amount of sediment

max runoff rate from a 10 yr storm

and build oversize to allow sediment accumulation

What would need to be done to stabalize the banks of an eroding stream bank?

put up fences to keep out livestock

remove fallen debris (trees, shrubs) or adjacent trees

grade bank to make slope 1.5:1 or less

vegetative cover, maybe, that is erosion resistant and water tolerant

weathered rock fragments with enough fine materials to make it flow like a mudflow when saturated with water

turn into a stony material

water- lubricant

gravity- driving force

earthquake/ movement- trigger

mainly occur on slopes

providing drainage keeps excess water from accumulating

lots of vegetation cover

structural support

strong winds blow across an area that serves as a sand source

cover down wind vegetation

how to curtail the effects of sand dunes?

have a vegetation cover

have a mechanical shelterbelt to reduce wind velocity

plant salt-tolerant vegetation, as plants not seeds, and use fertilizers in the spring

possibly add sant to area to create a steady state of sand, either in the front or the back depending on geog

is it possible to stablize a sand dune too well?

how to stablize dunes of the great lakes?

start: windward side of the dune

Plant a variety of vegetation in several rows

how to stabalize inland dunes?

(2 techniques)

1. Irrigation- level dunes to less than 5%, fertilize according to tests, and plant alfalfa, corn, wheat or potatoes. Leave crop residues until next growing season.

2. Non-irrigation- plant salt resistant plants prior to rainy season

Why would a dune need leveling?

reduce the slope gradient

make the deposits thinner

permit deep plant roots to reach finer-textured soils

areas of high elevation

growing season is 60 days

wind is strong

most precipitation is snow

soil usually thin, rocky and infertile

occur at high latitudes, cold temp

short growing season

soils are shallow and usually under permafrost