Some rhetorical questions:
1. Why aren't you using ZFS which checksums all data so that it can confirm all data is read and written without bit errors?
2. Why aren't you using ZFS mirrored volumes so that ZFS can automatically provide the correct data in the face of one drive returning bit-corrupted data?
3. (With ZFS ECC RAM is strongly recommended, and seems pointless without it). If you didn't have ECC RAM how do you know your data wasn't affected by bit errors before being written to the drive?
None of this is advice to use ZFS, just that it is reportedly the safest way to store your data if you care about it that much.
As NTFS doesn't have checksum data, then unless you have done that yourself, there is no way to be certain that there aren't already bit errors in your data. This is before you even think about using GParted (or not) to copy it.
GParted can't add checksums to file systems that don't have them, as that would make them incompatible and be unreadable by anything else.
GParted can't add checksums to the host to drive communication.
If a bit flips on a drive platter and the drive says error instead of return the data from a particular sector then there is nothing GParted can do other than report that error and stop when copying the data. (Hard disk drives do checksum every sector of data however those checksums are *NEVER* available to the computer or user. The drive either returns the data, because it matches the checksum, or it returns a read error and you'll never get that sector's data again). In such cases specialist data recovery tools are needed. Ddrescue is a tool that can try to read as much data as possible from a drive which has failed sectors. It will try to re-read the failed sectors again, though the drive will have already tried for 8 to 120 seconds and each subsequent attempt to read a failed sector will incur the same lengthy retry cycle. Ddrescue is available on the GParted Live CD/USB along with other rescue systems and many distributions.
As a practical but technical and lengthy suggestion try this:
1. Prepare the destination hard drive with the same size partition.
2. Use ddrescue to copy your NTFS from the source to new destination partition.
3. Run md5sum on the source and destination partitions.
If the md5sums match then the copy didn't introduce any bit errors. Each md5sum run will take approximately as long as the data copy. 3 time longer in total.