Are these the same course? I've checked them both in the undergraduate timetable and they are offered at the same time in the same buildings as I believe. Hows the work load in this course as an elective and in terms of scoring a good GPA?

The courses are the same. I was told that the difference is kinda up to you, if youre aiming for a minor in say, Enviro Sci, then choose that course code instead of Earth Sci.

If you have Bernier, hes very fair, you only need to learn whats in his slides, he tells you what to study and how much things will be worth on the exam, and the labs are easy marks. I got a 10 without too much stress

This course is an intro course in general environmental science so it covers a broad range of topics. The labs are pretty straight forward and the midtermand exam are easy if you put in a bit of effort studying.