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Sand is the essential ingredient that makes modern life possible. Believe it or not, we use more of this natural resource than any other except water and air. Sand is the thing modern cities are made of. But now we are starting to run out.
That's mainly because the number and size of cities is exploding, especially in the developing world. Every year there are more people on the planet, and every year more of them move to cities. To build those cities, people are pulling untold amounts of sand out of the ground. Usable sand is a finite resource. Desert sand, shaped more by wind than by water, generally doesn't work for construction. To get the sand we need, we are stripping riverbeds, floodplains and beaches.
Extracting the stuff is an estimated $70 billion industry. It runs the gamut from multinational companies' deploying enormous ships to villagers carrying shovels and buckets. In places where onshore sources have been exhausted, sand miners are turning to the seas.
This often inflicts terrible costs on the environment. In India, river sand mining is killing countless fish and birds. In Indonesia, some two dozen small islands are believed to have disappeared since 2005 because of sand mining. Environmentalists tie sand mining in San Francisco Bay to the erosion of nearby beaches.
People are getting hurt, too. Sand mining has been blamed for accidental deaths in Saudi Arabia, South Africa and Gambia. In India and Indonesia, activists and government officials confronting black-market sand mining gangs have been killed.
Stronger regulations can prevent a lot of this damage, and do in most developed countries. But there's a downside. Sand is tremendously heavy, which makes it expensive to transport. If you forbid sand mining in your backyard—as many American communities are trying to do—then it has to be trucked in from somewhere else. That drives up the price. Concrete is relatively cheap; if the cost of making a new building or road were to double, it could hit the economy hard.
Not to mention the extra truck traffic and pollution. California state officials estimated that if the average hauling distance for sand and gravel increased to 50 miles from 25 miles, trucks would burn through nearly 50 million more gallons of diesel fuel every year.
It once seemed as if the planet had such boundless supplies of oil, water, trees and land. But none of those things are infinite, and the price we've paid so far for using them is going up fast. We're having to conserve, reuse, find alternatives for and generally get smarter about how we use those natural resources. That's how we need to start thinking about sand.
6. We can learn from the first two paragraphs that the rapid expansion of cities ______.
[A] has caused the population explosion
[B] has led to a large scale of migration
[C] has used up sand for construction
[D] has accelerated sand consumption
7. What do we learn about usable sand for construction?
[A] It is being extracted from all places possible.
[B] It has created an industry of high technology.
[C] It is now able to be exploited in the deserts.
[D] It is a limited resource shaped by wind.
8. Which of the following would be the most serious victim of sand mining?
[A] The ecosystems.
[B] The mining workers.
[C] The sand mining gangs.
[D] The environment activists.
9. Regulations to prevent sand mining damages may lead to ______.
[A] the disturbance of local communities
[B] unnecessary building of roads for transport
[C] higher construction and environment costs
[D] twice as much traffic and fuel consumption
10. It can be concluded in the last paragraph that ______.
[A] alternative resources can save the planet
[B] ways of using sand should be improved
[C] the price of sand is increasing rapidly
[D] we need to improve supplies of sand