Looking at the distances and taking previous posts at face value
One quoted take off distance for 36L is 4446m
Looking at Google Earth a rough measure shows from the southern end: -
350m of "white" coloured surface
3090m of "black" top surface ending just past the piano keys for 18R and level with the first left hand turn off (possibly high speed) heading north
1000m of light coloured surface, ending just before a perimeter road and with another left hand turn off.
The above added together equal 4440m
A quote from an Iberia Captain makes reference to the skid marks and wheel tracks, possibly from this flight, in the grass to the right, at or about the first left hand turn off
A map, posted from the press, shows the a/c veer off location as this