So I just finished first year, and failed a mandatory course in order to get into any of my second year programs. I can't take it this summer, so I will have to take it in the fall, but what does this mean? I know I will have to go undeclared, but I'm not sure exactly what that means.

Undeclared major means you are not registered in a specific major. This will impact your course selection as many courses will require you to be in a certain level and a certain major in order to be fully registered.

If you're staying in Enviro Sci you won't have much difficulty. You just won't be able to take the courses that specifically list that course as a prerequisite. Make an appointment with your academic advisor (Dr. Luc Bernier - [email protected]) and he'll help you sort out which courses you can take.