The nuke plant isn't tricky. The RR came before it and the charter is intact. You obviously just need to have some interagency cooperation on the maintenance windows, and emergency protocol filed in the event that a disabled train needs to be evacuated on the property. But that's it. And the plant is old; it's not going to be active too many decades longer.We’ve definitely discussed the Eastern Route on AB and I recall:
1) getting through the nuke plant at Seabrook was tricky
2) I don’t remember that there were full breaks in the ROW, just a rail trail issue
3) the bridge In Newburyport $$$
There are no breaks in the ROW. In Downtown Newburyport and (partially) Salisbury you have standard revokable 99-year rail trail leases. That of course comes with all the standard challenges of trying to de-landbank a ROW, but if it can be done anywhere it can be done here.
The bridge in Newburyport would have to have its derelict swing span replaced with something new, and one set of girders on a small portion of the Newburyport-side approach span were chopped down to build the Harborwalk below, but a feasibility study 20 years ago found the approach spans to be in solid structural shape so some recycling of infrastructure is feasible for cutting down the cost.
The last feasibility study found solid ridership and an attractively fast schedule for the service. The problem is simply schizo NH politics. If a slam-dunk like the Capitol Corridor can't get through a single legislative session of short-attention span political theatre there's very little hope for a longer-game (if straightforward) service restoration with de-landbanking like this. There has to be a sea change in how Live Free Or Die politics approaches transit.