The report indicates that a bad cement seal on the oil well allowed gas and other liquids to flow up the production pipe.

这份报告表示，油井上一个有问题的水泥塞使得天然气和其他液体通过生产管道涌向海面。

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Engineers had spent days pumping heavy drilling fluid into the leaking well head on the ocean floor in a high-pressure bid to smother the gushing crude and ultimately seal the well with cement.

工程师们数日来一直向海底的泄漏油井泵入大量的钻探泥浆，希望用高压堵住喷涌的原油，最后用水泥封死油井。

youdao

If a stable column of mud has been set up in the well, keeping the oil at bay through its sheer weight, the next step would be to set cement in the well and seal it off permanently.

如果一个稳定的泥浆柱能在油井里成型，并通过它十足的压力将石油限制在海湾范围，那下一步就是将井里的泥浆粘合好，使油井永久封闭。

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Workers later added cement to harden in the well to seal it permanently.

VOA: special.2010.08.07

The team then failed to run a test to establish that the cement seal was adequate.

ECONOMIST: BP casts the blame for the Gulf oil spill widely

Most of the technical issues covered in the report, such as the failure of a crucial cement seal and the misinterpretation of a key pressure test, have been raised by other investigations.

WSJ: Gulf Disaster Tied to BP's Lack of 'Operating Discipline'

Cement used to seal the well was provided by Halliburton.

BBC: BP: Gulf of Mexico oil spill 'shared responsibility'