[tscs37]

I remember reading up on the BND (German Intelligence Agency) Guidelines on how they wipe their data.

They basically wipe the drive first and verify it appears to be wiped and then shred it. The highest level allows for only 0.5mm^2 sized particles with tolerance up to 1.5mm^2.

If data is encrypted, then in theory destroying the key should be sufficient given that the encryption is good (Chapoly or AES)

[kevincox]

It also depends on how long you want the data to be safe. So if you are storing user data you probably don't want to release drives containing encrypted user data as you don't long they wanted that data to remain secret for.

Imagine that your user was Coca-cola and they uploaded their recipe. They wouldn't be happy if in 100 years the encryption was cracked.

Far fetched, maybe slightly but a real consideration.

[tscs37]

Well, yes, that's what you shredder them for.