Applying for an outside fellowship (such as NSF, or EPA-STAR, etc) can be a little complicated. Some require that you go through SPO before you can apply, but not all of them. And it can change from year to year whether you need to go through SPO. Find out early, and if you do have to go through SPO you will need to submit your proposal to the ESPM Grants & Contracts office two weeks before the grant deadline. They will submit it to SPO for approval, and then it will be returned to you to submit the final draft. You are allowed to continue editing it during this time, but you can't change the major content of the proposal.