I will repeat everybody’s question: Why?
The best colleges for an undergraduate degree in Environmental Policy are not in the T-20s. In fact, the majority of the top programs for environmental policy are in the T-50 or even T-100. Top programs (I mean really the very top) include V-Tech, Syracuse, UC Davis, U Vermont, U Maine, and others.
Unless you want to transfer to a more highly regarded program in environmental policy, there is no reason for you to transfer, and these programs are mostly not in the colleges that are called “T-20 colleges”.