CHICAGO & RIO DE JANEIRO--(BUSINESS WIRE)--Fitch Ratings has affirmed the long-term local and foreign currency Issuer Default Ratings (IDRs) of Samarco Mineracao S.A. (Samarco) at 'BBB' and the National Scale Rating at 'AAA(bra)'. A full list of rating actions follows at the end of this release. Samarco benefits from its ownership under two industry leaders, Vale S.A. (Vale; 'BBB+'/Outlook Stable) and BHP Billiton Limited/Plc (BHPB; 'A+'/Outlook Negative), with each company owning 50% of Samarc