ARCO ARCO was formed by the merger of East Coast–based Atlantic Refining and California-based Richfield Oil Corporation in 1966; the company’s name is an acronym of the two companies’ names. A merger in 1969, brought in Sinclair Oil Corporation. Website Contact Organizer Contact Organizer Contact Person Name* Contact Person Email* Contact Person Message* Contact Person Phone No* Cancel Send Current Events Upcoming Events Past Events There are currently no events. There are currently no events. There are currently no events.