Prime Time did not identify the source of the information disclosed in its TV programme. There is no need; that information could only come from within Transroute (or, possibly, but unlikely, NRA). Transroute [ironically its website is "under construction"] has, since the airing of the Prime Time programme, recognized SIPTU as the representative of Transroute’s employees working on the Tunnel. In short, the Prime Time insider/source is a Transroute employee, a member of SIPTU and a whistleblower.
Connected with this subject is the Government assault, [by the Freedom of Information (Amendment) Act 2003] on Freedom of Information principles.
For a history of FOI in Ireland (as of 2003) see HERE.
The Tunnel’s faults will be the news story when there is an accident, possibly a very serious one; whistleblowing is a mechanism to forestall such an event and is valuable for that reason.
Of one thing we can be sure; a government led by Bertie Ahern will not introduce legislative protection for whistleblowers.
(Which is not to say he is alone in his attitude).