Mae rhai o’r deunyddiau hyn yn cael eu defnyddio gan Gomisiwn Trafnidiaeth De-ddwyrain Cymru ac, felly, gellid gwireddu eu gwerth drwy eu defnyddio ar gyfer amrediad o brosiectau neu raglenni seilwaith eraill, ac mae ganddynt werth posibl yn y dyfodol. Mae cryn dir a nifer o adeiladau a brynwyd fel rhan o’r gwaith, y mae ganddynt werth ar gyfer y dyfodol, wedi cael eu cynnwys yn y costau sydd ar ôl.
Some of this material is currently being used by the South East Wales Transport Commission and its value could therefore be realised through its use on a range of other potential infrastructure projects or programmes and has a potential future value.  Included in the remaining costs are significant amounts on land and buildings acquired as part of the development work which also have a future value.