The yellow route has a roughly 1% uphill grade from east to west, climbing about 65’, from an elevation of 240’ under Hammond Road, to 305’ next to Norfolk Avenue, over a distance of 6500’. Curves are roughly 5 degree, 1100’ radius, which according to standard US railroad practices, could accommodate operations at 40mph with run-of-the Mill superelevation of 3", and unbalance of a further 3".
This is easily in line with other curves, grades, and speeds on the line - so it wouldn’t impose any constraints that don’t already exist.
The route would pass under South Wilmington at an elevation of 258’, where the road is currently at 270’. Conservatively you need about 30’ of grade difference for a road over a railroad to accommodate double stack freight, future electrification, and a 6’ deep substructure for the road. So South Wilmington would have to be raised by 18’, which (given the industrial context) would not be controversial. Cutting the clearance requirement by leaving out future electrification and/or double-stack freight could save money and reduce impacts. But even the most strenuous of requirements that the RR could impose can be easily accommodated.
The route would easily clear South Saunders, at an elevation of 276’ where the road has an elevation of 240’, which is 36’ of clearance- where 25’ is about what is needed for the simplest type of span, a ballasted deck steel beam girder bridge with 16’-17’ of clearance below. Incidentally 276’ is the same elevation as the I-40 bridge over South Saunders, so it would fit right in.
There would be a few structure impacts, including 8 houses along Granite Street, Marble Street, and Norfolk Avenue, plus two commercial buildings and part of a self storage complex on South Wilmington. Beyond that, it would take a small corner of the Sam’s Club parking lot, and require the 40/Saunders interchange to be reconfigured (probably to a diamond or DDI.) It has a big impact on the Kane/Malik land but since that isn’t developed and (as far as I know) no master plan has been drawn up yet, there is probably a (closing) window of opportunity to make this happen.