Not concise:

I think the risks of hydraulic fracturing clearly outweigh the benefits.

Concise:

The risks of hydraulic fracturing clearly outweigh the benefits.

Comment:

You almost never need to write “I think” or “I believe” in an academic paper. Readers will assume you think or believe something if you’ve taken the time and energy to write it in your paper.

Notice also that the concise sentence above feels bolder and more convincing. Writing students often use phrases like “I think” because they’re trying to point out that they know they could be wrong. In life in general it’s admirable to remember that you could be wrong about something, but your writing should be as clear and convincing as possible. State your idea boldly and confidently. If there are factors that could make your assertion incorrect, then clearly state what they are and how likely they are to influence your claim.