Greenpeace volunteers Friday succeeded in boarding a North Sea drilling rig for the second time this week in a bid to derail oil company drilling campaigns on the UK Continental Shelf. At 0630 BST, six climbers from the environmental activist group scaled the Santa Fe 135 rig on contract to BG International PLC for drilling operations at its Blake field, located 30 km off the Scottish coast on Block 13/24 in the Outer Moray Firth.