Take out your soil lab Prepare for some notes! APES 12/7 & 12/8 Take out your soil lab Prepare for some notes!

Soil Lab Analysis Compare answers to your pre and post- lab questions Be prepared to ask me for clarification in 5 minutes!

Soil Properties and Degradation by Mining

Particle Size Biggest  Smallest Sand, Silt, Clay Fine particles have higher cohesion; that’s why water can’t get through clay as well Using a soil triangle: start at clay side and go horizontally; then to silt side and go downward diagonally; finally to sand side and diagonally left.

Other Physical Properties You should know porosity and permeability using the lab as the teaching tool. Porosity = how much water soil holds; permeability = how fast water flows through

Chemical Properties 1. pH 2. Cation Exchange Capacity = ability of soil to absorb/release pos. charged ions (cations) Plants need Na+, K+, Mg2+, Ca2+ Clay has a high CEC (b/c of neg. particles) BUT if there’s too much clay, it absorbs water and drowns plant roots FYI, humus also has high CEC

Chemical Properties 3. Base Saturation = ratio of base:acid in soil Bases are acceptors of extra H+; high ratio means lots of bases present to take in extra H+ from acids that might harm plant roots We have lots of limestone in NW soil to counteract acids (high base saturation)

Soil! Now we know all about it… Let’s see how we’re destroying it  Method #1: Mining

Minerals and Ores Earth’s crust is 88% iron, silicon, aluminum, and oxygen Valuable, rarer elements are found in uneven clusters because of variable distribution of rock types Mineral = naturally occurring, crystalline solid Ore = valuable, concentrated accumulation of minerals in rocks

Important Ores Metallic minerals- valuable for ability to conduct electricity, structural purposes, etc. (i.e, copper, gold, lead, rare earth metals for batteries) Salt, sand Fossil fuels (carbon-based)

MANGANESE COAL IRON MICA

What do we mine for? Energy Metallic Non-metallic Ferrous Non-ferrous Limestone Coal Iron Gold Nitrate Petroleum Manganese Silver Potash Natural Gas Chromite Copper Dolomite Pyrite Lead Mica Tungsten Bauxite Gypsum Nickel Tin Cobalt Magnesium

Costs of Mining Why is mining so terrible for the soil and underlying bedrock? Let’s explore!

Mining Simulation Lab Materials Group Roles Field Geologist (looks for ore) Accountant (keeps track of $$$) Miner (digger/transporter) 2 Process engineers (deshell ore) 2 Env. Engineers (clean up) Bucket with your mining site Small cup (your truck) Forceps Wooden skewers Paintbrushes Data table

Rules and Regulations You are trying to mine as many ores as possible to turn a profit You cannot touch anything directly with your fingers except for animals We will mine for 15 days (each minute = 1 day) a. 30 sec of daylight for mining, 30 seconds of dark for clean- up/accounting You must keep your mine shell-free or you will be fined At the end of the 15 days, you will do your final accounting and clean up (you will be fined $10 if you don’t follow the Surface Mining Control and Reclamation Act of 1977 that says you must restore your land to its pre-mining state)

Pre-Lab Planning (15 min.) Decide on a company name and write it on the board Make a data table to track your profits and expenses (one only-won’t be turned in) Sketch your pre-mined site in section 3 of your lab book Decide on up-front expenses: Buy a mine site for $5 or $2 + 10% final profit? Buy a reclamation bond for $5 (insurance to avoid fine at end)? Buy trucks and extra tools? Remove rocks, houses, animals? (see costs)

Let’s Play! Accountants: record your pre-opening expenses

Due Next Time…. Lab Questions 3, 6, 10, 12, 13, 14 Mining FRQ

Mining Basics How are sites selected? consider env. cost, potential profits, amt. and stability of overburden (materials that must be removed to reach the mineral) Types of Mining Surface Mining (strip mining, open-pit mining, mountaintop removal, placer mining( Subsurface mining

Surface Mining Strip Mining: removal of mineral deposits in horizontal strips Land is clear-cut and overburden is removed by explosives/heavy equipment Mineral deposits removed by huge power shovels Overburden is replaced Land cannot be returned to original state, and heavy equipment compacts soil. Long-term damage.

Iron-Ore Mine, Liberia Iron-ore mines like this one have altered the landscape of Liberia. The Liberian Civil War (1989-1996) and the declining world demand for iron ore led to the complete shutdown of Liberian iron-ore mining in the early 1990s. Coal Mine in Appalachia

Surface Mining 2. Mountaintop removal Entire top of a mountain is removed by explosives, causing it to fall into surrounding valleys Common in coal mining in Eastern U.S. Permanently buries streams, alters topography

Surface Mining 3. Open-Pit Mining A huge hole is dug using explosives and heavy equipment; ore is removed Pit is abandoned and often fills with water Pit becomes acidic and polluted with heavy metals due to mine waste left behind Acid Mine Drainage: Sulfur compounds are oxidized by air, dissolve in rain water to form sulfuric acid run-off!

One of North America’s largest open-pit copper mines, located in Kennecott, Utah.

Surface Mining 4. Placer Mining Searching for ores in river sediments (i.e. California Gold Rush of mid-1800’s Rivers are diverted, dammed to make extraction easier Mercury is used to chemically remove gold from ores, polluting rivers https://www.youtube.com/watch?v=TbI_ZArJ22U

Subsurface Mining Deep, vertical shafts are drilled with horizontal branches Less surface env. degradation, but can cause collapse, explosions (methane and coal dust) Not just for coal!- any ore too far down to remove overburden

Types of Coal Mining Often called mountaintop removal

Downsides of Subsurface Mining Labor Intensive Filling in mines after they are empty Health of workers  Black lung disease, high rates of cancer from particulate matters Danger of accidents

Major Coal Mining Accidents http://www.cnn.com/2013/07/13/us/u-s-mine-disasters-fast-facts/ China is by far the most dangerous! 2010 collapse in Chile

Environmental Impacts Clear-cutting of forests Destruction of soil horizons Soil compaction Stream/river destruction, diversion, pollution Acidic and metallic waste-water pollution Solid waste, toxic dust and emissions 75% if all solid waste in U.S. comes from mines! This waste is called “tailings” or mining spoils- unwanted waste material

Animas River Spill (8/2015) https://www.rt.com/usa/319439-epa-caused-colorado-mine-spill/

Important Legislation in U.S. 1. Surface Mining Control and Reclamation Act of 1977 (SMCRA) Land must be reclaimed after surface mining Clean up any pollution **Various levels of enforcement** 2. General Mining Law of 1872 Encourages exploration of mineral resources Corporations can buy large tracts of public land for cheap! Minor modifications, but critics argue companies aren’t paying enough taxes on royalties or cleaning up well.