When the well reaches a pool, oil usually rises up the well because of its density difference with water beneath it or because of the pressure of expanding gas trapped above it.

当井和一个水池相接时，油通常会从井里上升，因为它与井下的水的密度不同，或者因为停留在它上方的膨胀气体的压力。

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The gas industry, for example, USES several million gallons of freshwater when "fracking" a well, and the water is not recycled for drinking, thanks to the additives that are used.

以天然气产业为例，抽一口井，需要使用几百万加仑的水，由于使用了添加剂，用后又不回收做饮用水。

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Though BP has sought to do just that as it captures crude from its breached well, some of the gas has escaped containment efforts and has wound up in the water.

虽然在提取原油时，BP公司力求将油井漏出的甲烷收集或烧掉，但还是有些气体泄漏逃离，融入到水中。

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They allege that the company's drilling polluted their water with chemicals,metals and methane, the main constituent of natural gas, causing explosions as well as gastrointestinal and neurological illness.

VOA: standard.2010.01.02

There have been documented cases of leaking gas ruining nearby well water, of air pollution and of problems from the waste the drilling generates.

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Flowing hazardous chemicals(fracking fluid) poisoning land throughout how many miles of ground and surface water from the Gas Well Site?

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Contractors are moving gas and water pipes, as well as phone and electricity cables in Leith, so they will not be damaged when the trams are operational.

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