It would be covered in most planning conditions. The development would be subject to a full archaeological survey prior to a spade being lifted. During the course of the development archaeologists will periodically inspect the works and record any �finds�. This is called a �watching brief�. If anything of particular archaeological significance is found (i.e. anything rare or unexpected) then the works may be halted for further investigation. This is in accordance with planning authority requirements, in line with PPGs 15 and 16, and the 1997 EIA Directive.
Generally speaking though, in most situations the presence of the historical site is just recorded for posterity and any future development. Most of the developments I deal with are handled by the consulting division of MoLAS.
As said above, English Heritage may also have a particular interest:
http://www.english-heritage.org.uk/server/show /conWebDoc.2402