- Key facts
- It's a stretch, but imagine you're an Eskimo living 1,500 years ago
- Where does petroleum come from?
- How much energy does petroleum provide?
- How much petroleum is there, and how long will it last?
- Geography is against us
- Where might new oil reserves be found?
- Two unconventional sources of oil: oil shales and tar sands
- Growing worldwide competition for a dwindling resource
- If supplies are dwindling, why watch petroleum go up in smoke?
- Environmental effects of petroleum
- Petroleum exploration versus conservation of endangered species
- The bottom line
Environmental effects of petroleum
Petroleum causes pollution at every stage, from mining and recovery to refining, transporting, and using it as fuel. Drilling wells can cause direct pollution via oil spills. Drilling also often involves injecting watery liquids into the wells; later released as drilling muds, these cause their own toxic pollution.
The notorious Exxon Valdez oil spill taught us that transporting oil by tanker ships can lead to disaster. Transporting oil by pipeline or truck can also lead to spills, because pipes break and trucks sometimes have accidents.
Crude oil—oil as it comes out of the ground—is many chemicals mixed together, and these must be separated into gasoline, kerosene, diesel fuel, heating oil, and heavier materials. This is what a refinery does: Like a giant chemistry set, it heats crude oil and separates its chemicals according to their density. The strong odors that make passersby wrinkle their noses are petroleum chemicals that the refinery has released into the environment—chemical pollutants. Travelers nearing the end of the New Jersey Turnpike on their way to the tunnels into New York City know exactly what I'm talking about.
These are just an indication of the potential for refineries to leak chemicals into the air, soil, and groundwater; to suffer accidental fires and breakages that produce more pollution; and to create sites that are heavily toxic for future generations.
Effects of the Exxon Valdez Alaskan oil spill are still with us
On March 24,1989, the tanker Exxon Valdez spilled 10.8 million gallons of crude oil into Prince Edward Sound, Alaska. Although it was not the largest spill ever, the oil slick extended over 3,000 square miles and inflicted heavy damage. The wildlife affected have been estimated to include 250,000 to 500,000 seabirds, at least 1,000 sea otters, about 12 river otters, 300 harbor seals, 250 bald eagles, and 22 killer whales.43 Nearly 19 years later, the spill still affects Alaska's fisheries, and lawsuits over its effects include the Alaskan Eskimos' $2.5 billion suit for damages.44 Costs of this kind are not usually counted in tallying the total costs of petroleum.