If you were hiring a contractor to make repairs on your house, you would tell him / her what you want done and how you want it done. That’s scoping.
People are used to making comments on a draft EIS (Environmental Impact Statement), but that’s different. Those are critiques of the work performed.
-Scoping comments should focus on what you want studied, and how you want it studied. Scoping comments should apply to the entire proposed project, not just to your property.
Example –impacts to water supplies
People have commented to FERC that the construction of the pipeline could have a negative impact on their surface and subsurface water.
In a scoping comment, one should give a specific example and then generalize, by asking FERC to study the issue along the entire route. If possible, describe the methodology you want them to use, and the data you want them to provide.
See the complete presentation here.