How does it feel to like the subject you are studying (College)?

I know how you feel, its like wanting to be an english major, but you have to take history, algebra or some other class that is not english. I do not know your grades, are you doing well in school? If so then I say that you should think about doing an internship, where you can work for a company and see what you will actually do. If you want to do environmental engineer but not have to do technical stuff, maybe try the social side like working in a non-profit group environmental agency where you can use your interest but may not have to be too technical. You may also need a break, or maybe have too many classes. I know sometimes things turn out different than what we think, so if you really cannot see yourself waking up everyday and doing this job then you may need to change to something else within your interest.