that's why "most" sites are researched for years before they decide if it's going to be a good site for a wind farm...
i find it hard to believe that they would put a 180' concrete pillar into an underground waterway... not saying it's impossible...
oh and i didn't make those numbers up... it was from a fact sheet from the american wind energy association http://www.awea.org/pubs/factsheets.html