Forrest made headlines in 2011 for protesting the construction of a Montana railroad that would have facilitated coal extraction from the state because the proposed route passed through his ranch.

FORBES: Forrest Mars, Jr.

Gerwyn Williams, from UK Methane, has previously said coal bed methane extraction was already used safely worldwide.

BBC: Keynsham residents against natural gas extraction plans

It affects all "extraction" industries, including natural gas, coal, copper, diamonds and possibly timber.

FORBES: Seeing Through Big Oil

Suncor has run into an extra rich piece of ore with a high coal component, he said, which caused problems in the extraction process.

FORBES: Magazine Article