From your article (NCE last week) I am surprised that unexploded World War II bombs are considered a threat and could undermine development of the Thames Gateway. What happened to the Construction (Design & Management) regulations?
In a similar development for Dartford Park on the south side of the Thames estuary, with which I was involved in my role a planning supervisor, the regulations clearly indicated that a UXB survey and an archaeological survey would be among requirements before, and a necessary part of, any site investigation.
There are plenty of specialists in both these fields who can advise and undertake the necessary surveys.
In addition, any design risk assessment should include reference to the possibility of UXB in these circumstances, thereby alerting all parties to this at a later stage.
Lance Fogg, managing consultant, highways & transportation, Bank Chambers, Faulkner Street, Manchester M1 4EH