My point is that if there is enough money available for the very generous compensation they recommend for 20,000 people (combined populations of Bedfont and Stanwell), then spend it on road diversions and build the two rwys on open land west of the M25.
A brief look at Google Earth shows that it's not just the unimagineable cost of compensating these communities, which are much bigger than Sipson and Harmondsworth, but also draining the reservoirs which are elevated compared to the surrounding areas. The reservoir capacity would have to be replaced - where? Just not practical.
Same thing applies to the open land west of the M25 - not to mention turning Windsor into the runway overrrun area!
A third runway as originally proposed seems feasible and sensible but a fourth runway? Nah.