ATA Errors on new disks

Hi,

Summary,

I've replaced several drives and they all seem to be bad (5 out of 6 new WDC WD4002FFWX-68TZ4N0).  Are they really bad or is something wrong with my NAS box?  How do I delete the disk_info.log?  Clear Logs doesn't do it.  btw, I've attached my disk_info.log below.

I have a ReadyNAS 314 4-bay which worked fine for the first several months.  I then started getting ATA Error counts on 3 of the 4 Toshiba drives.  Not sure what sequence they started appearing as I was not closely monitoring the logs and did not have email alerts set up (I do now).  I decided to replace all 4 Toshiba drives with WD 4TB drives off the recommended drives list.  I powered down the NAS, removed the Toshiba's and installed the WD's and powered back on.  I had to go through the setup and then synchronization. Within minutes I was getting ATA errors on 3 of the 4 drives.  I downloaded the logs and looked in the disk_info.log and two drives were at over 100 ATA errors, 1 was at 17 and one was at 0.  I returned the two worst drives thinking the one with 17 may not really be bad and would wait and see how it performed.  The two new replacement WD's arrived, I hot swapped them one at a time letting the first hot swap fully synchronize (about 10 hours) before hot swapping the other one.  I let it fully sync (another 10 hours).  Those two are the ones in bay 1 and 3.  I am continuing to get ATA errors on the third drive so I have decided to replace it as it is now up to 1263 ATA Errors.  On top of that, according to the log, the 2nd, replacement WD is already at 13630 ATA Errors and the other one is at 53!  I am beginning to suspect the NAS device is bad and not the drives.  Also, I want to make sure the ATA Errors are reset to zero to make sure I am looking at logs for the currently installed drive.  Isn't that handled automatically when a disk is swapped?  Any thoughts or suggestions?   If I can't resolve this I am going to have to return all the new WD drives and trash the NAS box and eat the cost and never by NetGear products again.  I am new to this so please be nice.

btw, I have the latest firmware update. 6.6.0. 

Device:             sdb
Controller:         0
Channel:            0
Model:              WDC WD4002FFWX-68TZ4N0
Serial:             NHGHHS3Y
Firmware:           83.H0A83
Class:              SATA
RPM:                7200
Sectors:            7814037168
Pool:               data
PoolType:           RAID 5
PoolState:          1
PoolHostId:         2fe645e0
Health data
  ATA Error Count:                13630
  Reallocated Sectors:            0
  Reallocation Events:            0
  Spin Retry Count:               0
  Current Pending Sector Count:   0
  Uncorrectable Sector Count:     0
  Temperature:                    36
  Start/Stop Count:               1
  Power-On Hours:                 16
  Power Cycle Count:              1
  Load Cycle Count:               1

Device:             sdc
Controller:         0
Channel:            1
Model:              WDC WD4002FFWX-68TZ4N0
Serial:             K3G0KTMB
Firmware:           83.H0A83
Class:              SATA
RPM:                7200
Sectors:            7814037168
Pool:               data
PoolType:           RAID 5
PoolState:          1
PoolHostId:         2fe645e0
Health data
  ATA Error Count:                1263
  Reallocated Sectors:            0
  Reallocation Events:            0
  Spin Retry Count:               0
  Current Pending Sector Count:   0
  Uncorrectable Sector Count:     0
  Temperature:                    40
  Start/Stop Count:               3
  Power-On Hours:                 75
  Power Cycle Count:              3
  Load Cycle Count:               5

Device:             sda
Controller:         0
Channel:            2
Model:              WDC WD4002FFWX-68TZ4N0
Serial:             K3G0BZ2B
Firmware:           83.H0A83
Class:              SATA
RPM:                7200
Sectors:            7814037168
Pool:               data
PoolType:           RAID 5
PoolState:          1
PoolHostId:         2fe645e0
Health data
  ATA Error Count:                53
  Reallocated Sectors:            0
  Reallocation Events:            0
  Spin Retry Count:               0
  Current Pending Sector Count:   0
  Uncorrectable Sector Count:     0
  Temperature:                    40
  Start/Stop Count:               1
  Power-On Hours:                 62
  Power Cycle Count:              1
  Load Cycle Count:               3

Device:             sde
Controller:         0
Channel:            3
Model:              WDC WD4002FFWX-68TZ4N0
Serial:             NHGHHV3Y
Firmware:           83.H0A83
Class:              SATA
RPM:                7200
Sectors:            7814037168
Pool:               data
PoolType:           RAID 5
PoolState:          1
PoolHostId:         2fe645e0
Health data
  ATA Error Count:                0
  Reallocated Sectors:            0
  Reallocation Events:            0
  Spin Retry Count:               0
  Current Pending Sector Count:   0
  Uncorrectable Sector Count:     0
  Temperature:                    35
  Start/Stop Count:               3
  Power-On Hours:                 75
  Power Cycle Count:              3
  Load Cycle Count:               5