Congratulations on your offer!
While my knowledge of engineering is limited, studies of civil engineering with a focus on the environment would likely constitute a good combination. This is because a civil engineering approach that encompasses the concepts of structures and landscapes and the way these are constructed to blend with or protect the environment results in a potential advantage to the student, especially in our modern world, where environmental sustainability is sought and encouraged in a range of aspects and fields to a greater extent.
I hope this helps!