Plans to create Britain’s biggest quarry were scrapped yesterday, marking the end of Scotland’s longest-running planning dispute.  The cement manufacturer Lafarge Aggregates said that it was withdrawing from the quarry project at Lingerbay on Harris and halting all outstanding legal action.  The decision was welcomed by environmental groups which have been battling the "superquarry" plan since it was first proposed in 1991.  Duncan McLaren of Friends of the Earth Scotland said: "This is a great decision for the people and environment of Harris. Lafarge’s decision is without doubt the only responsible and ethical decision that could have been taken. It’s just a shame it has taken so long."  Green groups claimed that the quarry would have left a scar six times higher than the White Cliffs of Dover and reduced the Roineabhal mountain to a sea loch.