MELBOURNE (Standard&Poor's) Sept. 19, 2012—Standard&Poor's Ratings Services said today that its 'BB-' corporate credit and issue ratings on Australia-based mining company Fortescue Metals Group Ltd. (Fortescue) remain unchanged. The ratings are still on CreditWatch with negative implications, where they were placed on Sept. 12, 2012. This is despite the company's announcement that it has secured an underwritten commitment for a senior secured credit facility of up to US$4.5 billion. The facility will be used to refinance all existing bank facilities (about US$3.6 billion) and for general corporate purposes. In addition, the new facility has a five-year tenor and doesn't have any earnings-based covenants. The company's new facility is a positive development as it will remove the