Mumbai, July 10 -- The state forest department has allowed a branch of the Oil and Natural Gas Commission (ONGC) to carry out a 3D seismic survey for hydrocarbon exploration over an area of 15,212.8 hectares of forest land in Dhule and Nandurbar districts of northern Maharashtra. The ONGC's Dehradun based Geophysical Services and Frontier Basins will drill 4,754 holes, 32 per square km, with a 2.95 inch diameter, and will study the earth's surface and search for deposits of hydrocarbons like petrol and natural gas by creating and recording seismic waves. The order, issued on Wednesday by an undersecretary of the forest department, Ganesh Jadhao, says that the legal status of the forest land will not be changed. The order adds that before the project begins, the local deputy conservator of forests (DCF) must ensure that it does not disturb any protected area such as a national park, wildlife sanctuary, nature reserve, or tiger reserve. The department has also said no temporary lodging can be constructed for those working in the project, and no explosives can be stored in the forest. The order adds that the permission for drilling in the area does not allow the ONGC to state a claim on the land or use it for any other purpose. The order also directed the ONGC to make sure no trees are cut in the process, and to cover up the holes once the project is complete. It said with a local forest officer's permission a tractor-mounted drilling equipment can be used for drilling holes in pre-determined areas close to forest paths. The forest department has asked the ONGC to plant at least two saplings near every hole before leaving the site. If that is not possible, then it must pay the cost of two such plants, with their maintenance cost, for 10 years to the deputy conservator of forests. The ONGC spokesperson did not respond to queries from HT....