Shimla, July 27 After 17 years, one of the state's biggest mining projects is back on track. The National Mineral Development Corporation (NMDC) last week got government approval for its proposal to extract and sell steel-grade limestone from deposits in Arki of Solan district. A Government of India navratna PSU, NMDC had first struck a deal with the state government to mine limestone from Arki in 1991, but when its tie-ups with steel manufacturing units like SAIL did not work out because of economics of transporting limestone to steel factories down south, the project was shelved. Now, the NMDC has struck a deal with Gujarat Ambuja Cements Limited (GACL) to supply limestone to its cement factory in Suli. "The state's approval to the sale of limestone to Ambuja will pave the way for investment of several hundred crores in the state, besides huge royalty and taxes,' said Principal Secretary (Industries) Subhash Chand Negi. The state would get an estimated Rs 11 crore royalty per annum once the full capacity of deposit is exploited. The success of the project depends upon setting up of a rare industrial feat in the state, by which the transportation of limestone from quarries would be done through a cable conveyer system (overhead ropeway) over a distance of 10 kilometres from Arki to the GACL plant at Suli, near Darlaghat in Solan district. Later, the cable system would be extended to GACL's second cement plant near Ropar, with a 40-kilometre-long cable conveyor system (road distance being 130 kilometres). The state Industries Department has given permission for the project, but with a rider that the cable conveyor system would be mandatory for transportation of limestone. "The cable conveyor system would cost nearly Rs 750 crore and will be eco-friendly,' said Negi. When The Indian Express approached the NMDC officials for comments, they refused to reveal anything, saying that a delegation headed by their Chief Managing Director is expected to meet Chief Minister Prem Kumar Dhumal regarding the project later this week. The initial cost of the project in 1991 was Rs 282.47 crore. A major setback came when SAIL India backed out of the initial deal in 1993 because of poor economics involved in transportation to its Bokaro steel plant. All this while, Himachal also lost out on substantial revenue and collateral benefits in terms of jobs and development. As per the project, the extracted limestone will be sent through cable conveyor system to GACL at Suli near Darlaghat in Solan district in the first phase. Later, when the cable conveyor system comes up after six to seven years, the limestone transportation would be through Bharatgarh near Ropar in Punjab, from where some limestone would go to steel plants and some to the GACL cement plant at Ropar. The mining lease granted to NMDC on 233 hectares given by Himachal in 1991 would expire on August 2011. The Himachal government has given an ultimatum that if the operations are not started soon, the lease would not be renewed.