ConocoPhillips China, a subsidiary of the US oil giant, operates an oilfield in Bohai Bay in partnership with Chinese offshore oil producer China National Offshore Oil Company （CNOOC）, where a massive oil slick was detected on June 4 this year. The spill from the oilfield, which the United States＇ ConocoPhillips operates with China＇s state-run oil giant CNOOC, has polluted a total area of almost 4,250 square kilometers. The figures,