I posted this to Facebook:
I believe the hedgerow between the former Deer Park and the adjacent field, which runs roughly north south from Parlington Lane beyond the bank of beech trees by the east end of the Dark Arch towards Hook Moor. It looks like an ancient roadway, being a sunk pathway bounded on each side by hawthorn and fits well with my investigations into the use of Parlington Lane before the Dark Arch was built.
The area is outlined on the aerial view of the proposed site shown below. Essentially it appears to be a very old roadway, running from the corner of the field adjacent to an old pond near the east end of the Dark Arch towards Hook Moor. Additionally there is a sump by the pond which looks as if it was designed to collect water to be transferred to Parlington Lane. A cast iron pipe supplies the water, perhaps as a source of coolant for the train, after 1870. Bits of the system are still intact and there was a building nearby which is long gone. To anyone who knows the area it is by “Nellies Tree”. The building may have been introduced during WW2 and not be associated with the drainage system.