Speaking to Dave, the site manager, it's only affected the grassland between the woodland and the bog - missing the majority of the conservation work... bad news for sheep and meadow pipits, but could have been worse.
Fires here have always been common in summer, for the most part they're caused by human sources, fags & BBQ's..
Friend's just posted photos on Facebook; very large fire around there at the moment, 10 fire engines trying to put it out, not sure exactly what areas from the photos.