A fair amount of drug found in fish in Arctic plain (6)

I believe the answer is:

tundra

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(Other definitions for tundra that I've seen before include "Area with frozen subsoi" , "Arctic region of permafrost" , "Vast flat treeless zone" , "Treeless frozen Arctic plain" , "where you might see caribou" .)

I've seen this clue in the Irish Times (Crosaire) and The Irish Times.

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