Announcement video: https://www.facebook.com/DanielAndrewsMP/videos/268286560488175/
Strategic Assessment: https://bigbuild.vic.gov.au/__data/assets/pdf_file/0006/325572/Suburban-Rail-Loop-Strategic-Assessment.pdf
~12 new underground stations as well as interchanges with existing stations across all major existing train lines.
Cheltenham, Clayton, Monash, Glen Waverly, Burwood, Box Hill, Doncaster, Bundoora, Heidleberg, Reservoir, Fawkner, Broadmeadows, Airport, Sunshine, Werribee.
A 'real map' possible route alignment by Tayser from the skyscrapercity forums with added optional stations in green:
Just did a quick measure via gmaps - using the most direct lines/routes between the nominated stations I get to 95km.
The western side of the city is very awks and can see why the map even the gov produced is a bit wtf - L2 mentioned above if the Sunshine-Werribee section is the quad-tracks plus third side of the west Werribee triangle along the RRL alignment, the total length blows out to 112km (but admittedly, apart from 4-5km around sunshine, it's on the surface, not underground).
The first phase (Cheltenham-Box Hill) measures 24km.
The second phase (Box Hill-Airport) measures 35km.
The third phase direct (Airport-Sunshine-Werribee) measures 38km
The third phase alternative (Airport-Sunshine-Regional Rail Link-Werribee) measures 53km.
The stations in purple - what the government unveiled.
The stations in Green - my suggestions (East Keilor and Heatherton).