Mr. Aidan O'Connell:

The most aggressive environment in this whole pyrite, pyrrhotite and mica amphitheatre is the IS 398 scenario, which involves contaminated stone material containing high levels of pyrite right up against existing foundations. The matrix of a concrete foundation is quite strong. There are high levels of cement and it is well compacted in the context of it being placedin situin the foundations. In our experience to date, we have not seen any significant damage to foundations when they are placed in the most aggressive environment. That is why I have a relatively good sense in respect of foundation damage that may be arising from pyrite or mica within the concrete blocks. However, we will only get the proof of the pudding when we start repairing some of these properties - exposing foundations and examining them in volume. One cannot make a decision based on a very small catchment or number of properties.