Mr Richardson's late uncle, Sergeant Harold Richardson, is believed to be one of two Illawarra men buried with 400 Australian and British soldiers in the grave at Pheasant Wood following the Battle of Fromelles on July 19, 1916.

Sgt Richardson's name was included on the list of soldiers released by the Department of Defence last month.

Also named is Private Robert Gladstone Fenwick of Helensburgh, whose relatives have yet to be located.

Archaeologists began the task of exhuming the remains on Tuesday, and a team of 30 will spend the next four to five months removing the remains and any artefacts so the soldiers can be reburied at a cemetery being built in the town.

It is hoped scientists can extract viable DNA from the soldiers' teeth and bones and cross-match the results with genetic samples from their relatives so as many as possible can be reburied with headstones bearing their names.

Australian officials believe the grave contains about 191 Diggers.

Mr Richardson has put himself forward to provide the DNA sample, but has mixed emotions about the exhumation.