That is way above market. They must need it bad. Get an attorney.
What product? Natural Gas, Oil, or Salt Water
Take Jay's suggestion. Hire an experienced oil & gas attorney. There are many things you need covered. What use can you make of the right of way after the pipeline is installed? Agricultural? Can you drive over the pipeline? Will they remove the pipeline after it is no ;longer used?
Link to Mr. Camp's blog post mentioned above.
1. What SRT are you in?
2. How large a pipeline?
3. Who made the offer?
4. Did you take the offer, or are you still negotiating?