Hi Nicholas,
Long-term digital storage is a big project, with many variables to consider. You'll want to work with your IT department, since they'll be managing regular data backups, and you may want to consult with an archivist or librarian with data curation expertise.
Overall, the rule of thumb is 3/2/1, which means at least 3 copies of everything, in 2 different media, and at least 1 copy offsite (geographic diversity). For us, that looks like on-site servers, weekly tape backups (with daily incremental backups), and quarterly cloud backups. I've not stored data on DVDs, but with any medium you choose, you'll need to plan for reformatting over time, since everything will become obsolete at some point.
There's some very good information here:
Best Practices for Storing, Archiving and Preserving DataHope this helps, and good luck!
Karen
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Karen Urbec, MLIS, CA
Archivist and Digital Collections Specialist
Vizcaya Museum & Gardens
Miami FL
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