There is a big one at Leuven (between j22 and j23 - just after the split with the E314). Co-ords : 50.852748 / 4.657366)
A smaller one is located at Hoegaarden (between j25 and 26). co-ords : 50.752891 / 4.951776
Next one (also a smaller one) is located at Waremme (or Borgloon in Flemisch)...