<prompt> Bhala okuqhubekayo kwalesi sigaba - Lokhu kuchitheka kukaphethiloli kungokwesithathu ngobukhulu e-United States, kudlulwa kuphela i-Deepwater Horizon ne-Exxon Valdez  <response>: ukuchitheka kukawoyela. Kwaholela ekwandisweni koMnyango Wezangaphakathi endaweni yokulondoloza esiteshini futhi kwafaka isandla ekwakhiweni kwe-Environmental Protection Agency. 