Desperate to develop its own mineral deposits, resource-hungry India is trying to revive investment by taking aim at illegal miners like the sand mafia -- from a few hundred feet in the air.The government will deploy flying camera drones to track renegades who for years have been extracting everything from sand to coal to iron ore without permits. Unsanctioned diggers pay no tax, violate the mineral rights of others and employ rudimentary methods blamed for widespread environmental damage. They’re also hard to catch, working in remote areas and sometimes getting help from corrupt officials.“What happens in most of the cases is that when we reach those areas, people get a whiff of it and they run away, they remove their workers, they remove everything,” said Piyush Sharma, technical secretary at Indian Bureau of Mines in Nagpur , about 810 kilometers (500 miles) east of Mumbai in the center of the country. “Drones will be effective in a way that we will have pictures, which can be used as evidence.”Rogue miners have gotten so bad that the government in 2012 shut down all the iron ore pits in a western state that was the source of half India’s exports of the mineral. A judicial panel estimated illegal operators in Goa had siphoned off 349.4 billion rupees ($5 billion) of ore while dumping toxic waste in rivers and farmland and destroying forest habitat. The ban turned the country from the world’s third-largest exporter of iron ore to a net importer.One of the biggest mineral thefts is sand dredged from ocean beaches and river beds. Unlicensed extraction has caused flooding and threatened marine life like the endangered Gangetic dolphin. But demand for it as a building material in cement and concrete has soared with the expanding economy . In the year that starts April 1, the government plans to spend $59 billion to modernize railways, airports and roads. It also plans to build 10 million homes for the poor by 2019 and provide electricity to about 240 million people who don’t have it.Sand thieves aren’t the only problem. As growth in Asia’s second-largest economy fueled a surge in demand for imported raw materials, there’s been a lack of investment in domestic mineral reserves. Excessive delays in getting permits led foreign companies like Rio Tinto Group and South Korea’s Posco to withdraw huge projects in frustration, and Bangalore-based Deccan Gold Mines Ltd. hasn’t mined a single ounce of the metal after 13 years of trying.Using unmanned aerial surveillance of mines can help restore confidence in the government’s ability to protect mineral rights and control activity, according to Balvinder Kumar, India’s secretary of mines. In addition to tracking the illegal miners and their trucks, the government will have another tool in helping to monitor authorized operations, determine lease boundaries and aid in exploration.“In some of the states, illegal mining is a matter of concern as it is taking place on a very massive scale,” Kumar said by telephone from New Delhi. “Drones can help us find out how much material has been mined by a company and whether correct royalties or taxes have been paid to the government.”That’s a big improvement to the current system for monitoring mines and tracking cheats that relies on local complaints and unconfirmed reports, with few ways for the government to follow up to see if action was taken, according to the ministry. The government also began a mining surveillance program in October that employs satellite and remote-sensing technology to help curb illegal activities, according to the Indian Bureau of Mines.Last month, Tata Steel Ltd.’s Noamundi iron ore mine became the first in the country to use drone technology on an area spread over 1,160 hectares (2,866 acres) in the state of Jharkhand.State-run exploration agencies and the Indian Institute of Technology are studying drone use over river beds to identify potential trouble spots. Companies also can use thermal cameras in the drones to monitor mines at night, and the technology can provide images that make it easier to map exploration areas that might otherwise take months to complete on foot.The surveillance upgrade is just part of India’s bid to encourage more mineral investment. In 2015, the government of Prime Minister Narendra Modi decided to switch to competitive auctions for allocating resource rights, after years of discretionary or free allotments led to bruising corruption scandals. While most companies don’t like having to re-bid on deposits they find, the government says it wants a more transparent model. The process for getting licenses also was simplified.Those are the kinds of changes that Piyush Goyal, who helped to revive the country’s coal production, expects will lure more legal investments in domestic mineral extraction. Goyal, who is the minister of state with independent charge of power, coal, new and renewable energy and mines, predicts spending will surge more than sevenfold to 1 trillion rupees over five years, doubling mine output and reducing dependence on foreign raw materials.India imports almost all of the copper concentrate it uses and is one of the world’s biggest buyers of steel, aluminum, iron ore, gold and coal, Mines Ministry data show. But the country has yet to fully tap mineral riches that the government estimates are on par with those of major exporters like Canada, Australia, Brazil, South Africa, Chile and Mexico, according to the Central Statistical Organization.Only about 13 percent of 575,000 square kilometers with geological potential in India have been explored in detail so far, with minimal private sector involvement, according to the Federation of Indian Mineral Industries.Many of those countries are already using drone technology, as are other industries. Indonesia used them at tin mines and to track production at oil-palm and rubber plantations. China employs drones to monitor pollution, while some farmers use them to spread herbicides and photograph plants, according to the digital association Bitkom.“Drones are being recognized as the technology of the future,” said Sharma, the technical secretary at the Indian Bureau of Mines.