I'm assuming "no archiving log mode" is another way of saying that the "truncate log on checkpoint" database option is on.
Assuming you are on 15.7 or higher, you can free space on the log file using the "alter database off" command. See the documentation on Shrinking Databases.
This process will not cause the file itself to become any smaller, but the space freed on the log device will be available for use by other databases, i.e. other databases can be altered onto the device.
To actually make the file smaller, you would have to first shrink the database, then dump the database, drop it, drop the device, create the device with the smaller desired size, create the database for load, and load the dump.
-bret