The proposed second airport near Mumbai would come up by 2012 at an estimated cost of about Rs 4,000 crore, and would have a capacity to handle nearly 55 million passengers every year.The greenfield airport, which is likely to come up in the Copra-Panvel area, would be built through public-private partnership with private sector partner getting 74% and the remaining retained by Airports Authority of India, Maharashtra government and City and Industrial Development Corporation (CIDCO)."We hope to start and complete the bidding process in 2007. The land required is about 1,140 hectares for the core airport activity and the estimated cost will be between Rs 3,200-4,000 crore", Civil Aviation Minister Praful Patel told reporters after a meeting with Maharashtra Chief Minister Vilasrao Deshmukh today.Deshmukh said the International Civil Aviation Organisation (ICAO) has already given its techno-feasibility clearance to the Navi Mumbai airport.The two leaders also reviewed the situation relating to the development of the Nagpur airport as a national multi-modal hub to cater to domestic cargo and passenger traffic.Patel said additional land and infrastructure was required to expand the Nagpur airport for the purpose and an MoU would shortly be signed between Maharashtra Industrial Development Corporation (MIDC) and AAI.