Stumbled across this quite by chance, and wondered if anyone else was familiar? Synopsis reads:
Beneath Hill 60 (2010)
The extraordinary true story of Oliver Woodward. It's 1916 and Woodward must tear himself from his new young love to go to the mud and carnage of the Western Front. Deep beneath the German lines. Woodward and his secret platoon of Australian tunnelers fight to defend a leaking, labyrinthine tunnel system packed with enough high explosives to change the course of the War. Written by David Roach
Came across the film via a link on the Home page of a company called: SPARKEFILMS. Some of you may also find their website interesting.
http://www.sparkefilms.com/main.html
Dave Upton