The plain fact is, if there was a buffer zone around this place it would be safe. But there isn't and the Govt isn't likely to suggest there should be any time soon - just last week Eric Pickles issued wind farm guidance saying “Local planning authorities should not rule out otherwise acceptable renewable energy developments through inflexible rules on buffer zones or separation distances” - in other words “ignore the rules”

http://heritageaction.wordpress.com/2013/08/08/can-we-just-dispense-with-buffer-zones/
http://heritageaction.wordpress.com/2013/08/11/oswestry-hill-fort-under-attack/