Pedzisa mutsara unotevera: Muna 1989, "Exxon Valdez" yakarova matombo muPrince William Sound,
kudurura zvinopfuura zvemafuta asina kugadzirwa pamhenderekedzo yegungwa. Nhasi, kurwisana kuri pakati pemifungo yokusimudzira nokudzivirira kunooneka munhaurirano ine gakava pamusoro pokucherwa kwemafuta muArctic National Wildlife Refuge uye mugodhi unonzi Pebble Mine.