Archaeological excavations have identified the area of Confederate burials near the old Port Hudson town cemetery. There was a movement to have this land transferred to or purchased by the state of Louisiana and added to the Port Hudson State Historic Site. I am not sure that this occurred. Whether still on "private" land or state land, it is unlikely that permission will be granted to place markers at the cemetery site.
Back in the 1960s, markers were placed by the SCV or UDC on what were thought to be Confederate graves. Another archaeological excavation revealed that the burials were all post-war civilians.