Sir, - Dublin Corporation recently mounted an exhibition in Marino library in an attempt to calm local residents' apprehension over the proposed port access tunnel that would run beneath their homes - mine included.
A chief project engineer I spoke with at this exhibition assured me that, as a result of their own studies (and despite independent studies that suggest otherwise), the geological conditions of the ground beneath Marino is indeed suitable for the construction of a tunnel using the discredited New Austrian Tunnelling Method (NATM).
This involves spraying liquid concrete on to the unsupported walls of a tunnel shaft excavated using high explosives under our homes. There have been 39 documented reports world wide, demonstrating that NATM tunnels have an unfortunate tendency of collapsing, in on themselves.
Two of the test boreholes drilled last spring to test underground conditions in the Marino area were at least 600 metres apart, at either end of the avenue on which my house (and 39 others) are located. Extrapolating the results of two tests, and then asserting that the nature of the geological conditions beneath this avenue of houses (dating from 1928) would indeed be suitable for the excavation of a tunnel is, I believe, both spurious and unscientific.
As Dublin Corporation's engineers appear hell bent on pushing through their pet project, one wonders if they will drill their tunnel first, and apologise when, as a result of insufficient data, massive subsidence occurs above ground, damaging housing stock in the process. - Yours, etc.,
37 Croydon Park Avenue,
Marino, Dublin 3.