Gas Pipeline through our Farm

Dear Friends,

my farms is located near Thanjavur, Tamil Nadu. i have planted around 1500 timber trees like Kumil, Teak, Sandal, rose wood, mahogany, etc. all the trees around 3 years old. last July some body from ONGC department informed us that they will be laying pipe lines through our farms. we all farmers opposed and they left.last month some of our farmers received a letter from ONGC regarding the project. few farmers returned the letter, some received the letter. so we farmers arranged a meeting and planned to oppose it again at any cost. we have decided to send a legal notice to ONGC and District collector. now my concerns are.

  1. is there any way to stop the project legally?
  2. what is our rights? what is the law?
  3. Why cant ONGC take the pipe line through National High ways or State High ways? why are they interested to spoil farm land? is there any technical reason?