The process of extracting and separating gold in remote regions often results in environmental contamination with what?

Answer: mercury

Explanation:

A common method for gold extraction is by crushing the gold ore and mixing it with sand. Mercury is the added afterwards. An amalgam is formed which has a silvery appearance. This is the Gold - mercury amalgam. Some mercury may evaporate thereby contaminating the environment with mercury. The cyanide extraction process which involves reacting gold with hydrogen cyanide may also lead to cyanide contamination.