Fossil Fuels and the Environment Definition: complex hydrocarbons from dead organic matter. Stored suns energy, converted to chemical energy via incomplete decomposition.

Forms of Fossil Fuels 1)Crude Oil: found in sedimentary Deposits underground. -temperature and pressure cause organic deposits to chemically transform into oil. Reservoir Rock: porous geologic areas where oil is concentrated.Often consists of sandstone or limestone

Reservoir deposits are usually capped by a fine grained rock, which prevents the oil from coming to the surface.

Crude Oil Production Primary Production: pumping from wells under natural pressure in the oil field. -capable of only 25% recovery of the available reserve

Secondary, or Enhanced Production: high pressure water or steam is injected into secondary wells, to push the oil into the primary well. -various gasses are also used, such as carbon dioxide and nitrogen. -60% recovery is possible using these methods of drilling.

The Future of Oil The largest known reserves of oil are in The Middle East Although new reserves continue to be discovered, present reserves will most likely run out in the next few decades Assuming current levels of demand!

At the present rate of consumption, we years of proven oil reserves. Increased prices will make new reserves that are not now economically viable available in the future, but oil is still a non-renewable resource, with a finite availability.

But Wait!! What about CANADA??? Welcome to the ALBERTA TAR SANDS DEPOSIT

Proven Oil Reserves, 2000 Where the heck is CANADA?

Now look at 2007 data…

About two tons of tar sands are required to produce one barrel of oil. Roughly 75% of the bitumen can be recovered from sand. Though tar sands operations are required by law to return the areas in which they mine to the condition in which they found them, according to the report, "Most companies admit it is impossible to artificially return boreal forest to the same condition as they found it; instead reclaimed land will have much lower levels of carbon density and biodiversity than previously existed."

The Alberta government's Energy and Utilities Board (EUB) estimated in 2007 that about 173 billion barrels (27.5×10^ 9 m 3 ) of crude bitumen are economically recoverable from the three Alberta oil sands areas based on benchmark WTI market prices of $62 per barrel in 2006

2) Natural Gas: also a hydrocarbon, often found in association with oil deposits. Gas reserves are measured in cubic meters (m 3 ). The world reserve of recoverable gas is estimated at 140 trillion m 3.

Estimates of world consumption indicate that the reserves will last approximately 70 years. The U.S. has about a 30 year reserve of natural gas, at current levels of consumption. The U.S. has become a big importer of natural gas, because of increased consumption.

New discoveries at very deep depths may provide reserves for about 120 years. These reserves are economically risky to obtain, so may not be viable until fuel prices are high enough.

Until fairly recently, natural gas was considered a waste product of oil drilling, and was simply burned off. Natural gas is now considered a high value fuel, because it is clean burning and makes less pollution than other fossil fuels.

-Natural Gas consists mostly of methane (CH 4 ). It also contains small quantities of nitrogen, carbon dioxide, and sulfur compounds. Natural Gas is transported from areas outside the U.S. as Liquefied Natural Gas (LNG). How is Natural Gas Transported?

LNG is cooled to –260F, then transported in special insulated ships. It is then transferred to special depots, where it is then sent into pipelines to users.

3) Coal: solid, brittle, carbonaceous rock formed from ancient vegetation -Formed as a sediment, which is slowly covered over. -Current estimates indicate that coal reserves should years, at given usage rates

Types of coal: Anthracite (Hard coal):highest energy content, lowest sulfur content Bituminous Coal: lower energy content, Higher moisture and sulfur content Lignite (soft coal): lower energy content,higher moisture and sulfur content

Coal reserves are more evenly distributed globally than oil reserves. The United States has one of the largest reserves of coal in the world. Other reserves are in Asia and Europe

World Coal Reserves

Unfortunately, most of the coal reserves in the U.S. are soft coal or bituminous coal The burning of soft coal, with its high sulfur content, leads to sulfur dioxide pollution and acid rain. There are a few small deposits of anthracite, mostly in Pennsylvania

U.S. Coal Reserves

Environmental Effects of Coal Mining Most coal (60%) in the U.S. is “strip mined”, which is a form of surface mining. Strip mines are economically better, because many coal deposits are close to the surface, and strip mining is a cheap way to get at the coal.

Strip mining is very damaging to the Environment. Soil (overburden) is stripped away, exposing the coal deposit. The coal is then removed, and the ground is either left bare, or the overburden is then replaced, and restoration of the area is attempted.

An exposed seam of coal at the surface

A strip mine in Canada

Mountaintop mining in Virginia

In areas of high precipitation, acid runoff is a large problem. Acidic runoff forms from sulfur in the coal, and destroys waterways downstream from the mine.

Surface Mining Control and Reclamation Act of 1977 SMCRA grew out of a concern about the environmental effects of strip mining. SMCRA requires that mining companies post a bond sufficient to cover the cost of reclaiming the site. SMCRA prohibits surface mining altogether on certain lands, such as in National Parks and wilderness areas.