“Methane emissions from abandoned [oil and gas] wells will increase total emissions to double that of the oil and gas industry’s current output. … Fossil fuel producers have run off with their cash and left the public purse to clean up their mess.” (http://www.theecologist.org/News/news_round_up/2677596/disused_oil_and_gas_wells_wells_a_major_source_of_methane.html)

Well – adverb; in a good, proper, appropriate way, so as to bring about a fortunate outcome.