Question Mark bad sector on HDD with Chkdsk /r

[bgeo25]

My HDD has one or more bad sectors according to CrystalDiskInfo and HD Tune Pro. However, Windows did not detect any errors in the file system via Error Check.

These are the reported issues:
Current Pending Sector Count = 16
Uncorrectable Sector Count = 16

Error scan result:

My HDD is functioning like normal, so I'm trying to mark the bad sectors as unusable and then keep an eye out for more bad sectors in the future. I ran chkdsk /r D: and allowed it to run on the next restart.

When it finished, I saw several logs like this in Windows Event Viewer:
The device, \Device\Harddisk0\DR0, has a bad block.
and
Volume D: (\Device\HarddiskVolume6) is healthy. No action is needed.

However, CrystalDiskInfo and HD Tune Pro are still reporting Caution/Warning status due to the same issue as before. How can I tell if the sectors were marked as unusable? Is it worth replacing, even if no more issues arise?

HDD Info:
Seagate Barracuda 2TB 3.5" 7200RPM (ST2000DMZ08)

 

[ex_bubblehead]

This disk is actively failing. It could go total failure in the next 3 seconds or last another year. There's no way to predict when the drive will take its last breath so be prepared with a full backup and obtain a replacement drive ASAP.

 

[bgeo25]

I guess it's not worth keeping due to the uncertainty.. Any other opinions?

 

[USAFRet]

I agree with the above.

Start a comprehensive backup routine.
Today.

Use it until it actually dies, or becomes too unresponsive.