Seagate Savvio drive issues with T3600

I have a T3600 workstation that I got in April 2013.

It has two Seagate Savvio SAS 15K 146 GB drives on it.  These drives are not in a RAID configuration, but use the MegaRAID controller and PERC H310 adapter.

I have started getting a few "unrecoverable medium error" alerts from the controller for PD 1 / VD 1 (second drive), with block addresses around 0x7423a0.  This is about 7.6 million decimal, and the drive spec says that it has 512-byte blocks, so this comes out to about 3.8 GB.

This address is encompassed by a partition containing an 8 GB swap file (Windows 7).  I have 8 GB of RAM, and don't run memory-intensive applications, so I assume that the swap file is mostly just along for the ride.

The errors are coming out of the MegaRAID system, rather than from the OS or from applications that I run.  I'm aware that the hard drive system has the capability to handle some number of bad blocks without failing.

The errors tend to be most prominent in connection with coming out of sleep mode or going into sleep mode.  Several of the errors were picked up by a "Patrol Read" (anticipatory disk check), just after coming out of sleep early in the morning.

I have run pre-boot diagnostics that don't show any problems, but I don't think that they exercise the SAS drives.

I have several options to put the swap file somewhere else, and leave this region of the second drive unused.

Alternatively, I have an internal 128 GB SSD, and I could replace it with a bigger one and put the hard drive partitions onto it as well.

Or I could do nothing, and hope that the problem doesn't get any worse.

Any advice here?