suprised that you actually need to ask this question, as its only been 14 years or so in the planning. Its the opening stages of a freight terminal development, and is part of Peels overall plan part of which is the new terminal building, new hotels and facilities.
For anyone interested there's now about 50 detailed drawings etc on the Stockton BC website showing the whole south side development,
including the new acccess road, fencing, buildings, landscaping, etc.
http://www.planningwam.stockton.gov.uk/ ... 8/0728/FUL
look for the associated documents tab once you've found the application to see the