about 200 km I assume (never officially confirmed).
Not that it would really matter if it was targeted... The amount off fallout coming from the targets in the UK, France, belgium and Germany would probably kill us anyway...
wiki quote:
It is believed that since 1965, USAF nuclear weapons are stored at Volkel Air Base, to be used by the host nations aircraft. The USAF 703rd Munitions Support Squadron is in charge of maintaining and securing the weapons.As of 2008, 22 B61 nuclear bombs are believed to be in storage at Volkel, to be used by the Dutch 311 and 312 F-16 squadrons at the base. Despite clear evidence, the Dutch Ministry of Defence never officially acknowledges or denies the presence of nuclear weapons at Volkel.