Your PhD will likely be valued equally no matter what school you apply to. I think you have a good shot as a "unique" candidate to any of those schools. I think Duke is also growing an energy focus. You should cast your WE as related to oil and gas beyond just the retail aspect in order to tie it into your long term vision in the most favorable way. Play up the EPA focus you had and make it look like everything you've done both in and out of school has been preparing you for b-school and a career in the energy sector. It's all in how you pitch the story, and yours sounds pretty cohesive. Don't worry about your GPA. All b-schools know that engineering is a tough major. Plus your post-baccalaureate academics will more than satisfy any concern they have about GPA, and the longer ago it was, the more forgiving they are. I was a Georgia Tech undergrad with a 2.9 GPA and got into a top 5 school at age 31 with an interesting story and clear vision. You can too.
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Bryant Michaels
Admissions Consultant