Roedd cylch gwaith yr adolygiad yn un eang er mwyn i’r Panel fedru ystyried ystod eang o gynlluniau, a chyflwyno argymhellion am yr amodau pan mai adeiladu ffyrdd newydd yw'r peth iawn i'w wneud.
The review was defined in broad terms to enable the Panel to consider a wide range of schemes, and set out recommendations on the conditions where building new roads is the right thing to do.