Greenpeace should pay whatever it takes to return the site to its original condition. The miscreants that caused the damage should never leave jail.
From the article: "It's not a matter of money. The damage is irreparable." Due to the dry, windless, and stable climate of the plateau and its isolation, for the most part, the lines have been preserved since they were constructed by the Nazca Indians between 400-600 AD. The hummingbird etching was the most pristine of all of the figures and a revered cultural icon of the Peruvian people.
For Greenspeace to have desecrated the World Heritage archeological site, puts them on equal footing with other eco-terrorists, including the Taliban's destruction of the Bamiyan Buddhas in Afghanistan in 2001. How disgustingly ironic that the message they sought to send, "Time For Change: The Future Is Renewable" was done at a location and in such a way that it will never be able to be "renewed" to it's original form.
Greenspeace says that they are remorseful but that is not enough to bring back the site to it's original, untouched condition. Without even getting permission to do what they did from the government (which would never have been allowed), they are no different than any other criminals who violate the law. They should be arrested, tried, convicted and thrown into prison for their stupid, ignorant, self-serving ideology.