D2L defines ePortfolio as a tool for students that they can use as:
"...a personal portfolio tool for storing, organizing, reflecting on, and sharing items that represent your learning. You can include documents, graphics, audio files, videos, presentations, course work, etc. that demonstrate your improvement or mastery in a certain area. You decide what items you want to include in your ePortfolio, how you want to organize them, and who you want to share them with. "
For more information about how to use ePortfolio visit the student help pages, beginning at: http://help.d2l.arizona.edu/student/eportfolio-overview
As a course instructor you can control what Course Results students can import into their ePortfolio. See the following pages to see where this settings is within your course: