Day 5 - Mining Cookie lab, Mining & Forestry Notes

AP ? Of the Day

b) Acid drainage due to leaching of soil heaps by rainwater

Acid Mine Drainage Acid rock drainage occurs naturally within some environments as part of the rock weathering process BUT, this process is exacerbated by large-scale earth disturbances characteristic of mining and other large construction activities, usually within rocks containing an abundance of sulfide minerals.

Today… 1. Notes on Mining & Forestry (posted on web) 2. Complete the cookie mining lab Word of warning – these cookies are from LAST year’s lab. Some had ants on them. I wouldn’t eat them. Or those sugar cubes (you know who I’m talking to ). 3. After your group completes the lab, you have time to work on your chapter reading guides (posted on the website). 4. Remember – your test is NEXT time. Mrs. Davis will post an FRQ hint and maybe, if she has time, a review game! Check the website!

Mining What is mined? Minerals such as copper, silver, cobalt, aluminum, nickel, tungsten, magnesium, lead, uranium, potassium, and many others. Where from? The Earth’s lithosphere (crust) What else do we extract from the crust? Limestone, gypsum, gravel, salt, and gemstones

Minerals are a Non-Renewable Resource Most minerals are formed not in their pure form, but as ore Ore is a mixture of elements packed together Minerals are formed through geologic processes (such as cooling of molten magma)

Mineral Extraction Results In… 1. Habitat destruction due to removal of vegetation 2. Soil erosion 3. Acid runoff from extraction processes, contaminating soil and water 4. Air pollution as a result of fossil fuel combustion from machinery and smelting processes

Surface Mining How? Removes soil and rock covering mineral deposits Used when deposits are close to the surface Once extraction is complete, the hole is refilled with original rock/soil Impact Soil erosion Acid drainage Common use: gravel, sand, coal, oil sands

Mountain Top Removal How? Explosives are used to remove up to 400 vertical feet of mountain to expose coal seams Uses heavy equipment to move the overburden (rock or soil overlying a mineral deposit) downhill during strip mining for coal Common in the coal mines of the Appalachian Mountains Impact Deforestation Soil erosion Complete modification of local communities Common use: coal Top proven coal reserves (50%): US, former Soviet Union, China

Placer Mining How? Uses water to separate heavier minerals from lighter mud & debris Commonly used to extract deposits from river beds Impact Excessive debris in streams inhibiting biotic communities Erosion of stream banks Loss of riparian habitat Common use: gems, gold

Open-Pit Mining How? Digging to reach desired resource Terraced to allow vehicles in & out Commonly called quarries Impact Complete ecosystem destruction Acid drainage Common use: copper, iron, diamonds, gold, coal

Subsurface Mining How? Creates shafts deep underground to extract resources from pockets or seams of minerals Dynamite blasts, drilling and manual labor are used to remove excess rock Impact Health hazards to miners Acid drainage Common use: gold, copper, zinc, uranium, lead, nickel, coal

Hazards of Mining for Metals Heavy metal and acid contamination of surface and ground waters Potentially toxic to wildlife and animals

Mining Reclamation Reclamation = Restoration Costly because of the destructive nature of the mining Best reclamation = restoring vegetation to area previously mined Some are considered hazardous sites and require specialized clean-up as per the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Clean-up of Superfund sites is the job of the federal government and is paid for by a tax on the chemical and petroleum industries.

Forestry – The Challenge Balance humans use of wood products with the importance of forest ecosystems

Old Growth, Secondary Growth An old-growth forest — also termed primary forest, virgin forest, or primeval forest, is a forest that has attained great age without significant disturbance and thereby exhibits unique ecological features and might be classified as a climax community. A secondary forest (or second-growth forest) is a forest or woodland area which has re-grown after a major disturbance such as fire, insect infestation, or timber harvest, until a long enough period has passed so that the effects of the disturbance are no longer evident.

Deforestation Important facts Forests today are largely secondary growth Largest old-growth forest in the US is in Alaska Deforestation is happening on a grand scale in developing countries Impacts (world-wide) Loss of biodiversity Release of excess carbon into the atmosphere Reduced conversion of CO 2 into O 2 through photosynthesis Depletion of soil nutrients Desertification

Forestry Management Most harmful method: Clear Cutting This method takes all of the trees in an area leaving nothing standing. This can lead to all the deforestation problems on the previous slide – such as loss of biodiversity. Slightly better methods but both still leave most of the land bare: 1. Shelterwood systems – leave a low number of full grown trees to create shelter for emergent seedlings. A mix of small and large trees are selectively cut. 2. Seed-tree method – leaves only mature & seed producing trees so regrowth is assured. Best method: Selective Cutting: leaves most trees standing. Leaves trees of a variety of ages and reduces impact on habitats and ecosystems

Lab Time! Follow the directions. Every member of the group must actively participate – grades will reflect individual efforts. Have fun and good luck with your mining!