A number of politicians in northwestern Greece have grown weary of the pollution and health risks resulting from local coal mining. They are looking into an energy overhaul based on renewables. Driving through the northern Greek towns of Kozani, Ptolemaida, Amyntaio and Florina reveals a side of Greece that most tourists do not get to experience. There is no beach or sea in sight - instead, mines, coal piles and coal-burning power plants dot the landscape. The plants are run by the Public Power Corporation of Greece (DEI), which is mostly publicly owned. Environmental problems plague the region. About 80 percent of its power plants were built decades ago. They produce large amounts of pollution that breach EU environmental protection standards. This has led local governments to demand penalty payments from DEI. Greenpeace has also blamed the corporation for an increased death rate in the region. In 2007, a study by the Aristotle University of Thessaloniki found cancer to be the cause of about one-third of all deaths in Ptolemaida. According to Amyntaio Mayor Ioakim Iossifidis, DEI has also neglected its duty to restore vegetation in areas that have been mined. "The state, but especially DEI, have not played by the rules," he said. "The re-naturalization of mined surfaces is obligatory under the law."  Iossifidis added in spite of this, DEI continues to receive mining permits. He said cleaning up of the area damaged by mining would cost more than 5.75 billion euros ($7 billion), a bill noone can afford.