Sharpening his attack on Pranab Mukherjee, BJP-backed presidential nominee PA Sangma today said Rashtrapati Bhavan was being used as a "dumping ground" for the "failed" former Finance Minister. Mr Sangma is contesting against Mr Mukherjee in the presidential polls. "Raisina Hill is being used as a dumping ground for the failed Finance Minister," Mr Sangma, who was in Mumbai to mobilise support for his presidential bid, told reporters.