The plan has been criticized for tilting toward fossil fuel production, including a push to drill for oil in the Arctic National Wildlife Refuge in Alaska.

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He insists that in the push to drill the well quickly, the drillers lost circulation and got stuck, and had to regroup and drill a sidetrack well.

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Eventually, though, the drill will go deep enough to push rock powder into the drill's sample-gathering chamber.

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That was as deep as one could look into the earth with the available geological tools--and also about as far into the ground as anyone knew how to drill a well and push pipe into the hole.

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So, the command was given to drill a second hole that was deep enough to push some cuttings into the tool's sample acquisition chamber.

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