May I ask where the test track is?
Hi as posted by others it is also know as Old Dalby test track and runs from just south of Melton from a junction on the Syston Peterborough line north West to the edge of Nottingham near the A46 intersection with the A606 at Edwalton. It has OHE, installed since the 70s when it was used to test and develop the APT and APT-E and was used by BR for many years in research including the spectacular crashing of a class 46 into a nuclear flask besides the then open Old Dalby REME army base
Asfordby mine was built in the late 80s and started to use the line to extract coal but after this was closed due to geo conditions, the buildings were used by manf for the pendelino shake down tests which were completed a few years back and the future then looked bleak, but LU stock is now being tested on a section after the extra electrified 2 rails were added.
OHE is rumoured to be kept live to prevent theft of cable despite not being used.
It is a very scenic line with plenty of tunnels and would make a fantastic preserved line. The re-connection to Nottingham has been explored but would cost too much, due to buliding on the trackbed at Bridgeford although if the new Forest football stadium at Plumtree gets planning, then it is right next to the present track so something might happen, even if its just trams on the northen section