Tons of disk not ejected properly notifications after wake, a quick solution
Whenever I put my iMac to sleep the USB drives go to sleep with the system but then wake up on their own due to their own power management protocols and wake the mac temporarily or something. This sequence loops throughout the night and causing the mac to display a boat load of notifications warning me that the disk(s) were not correctly unmounted.
To resolve this I have to click close to each message one by one and there are literally so many that I end up clicking countless times.
Solution: Open Activity monitor and Quit the Notification Center (it will relaunch) but all the notifications are removed, freeing me of endless clicking to dismiss each notfication one by one.
Hope this info helps out others.