Other, implicit costs include the social or environmental costs. Just as smokestacks in the past represented progress, wind turbines can be seen as symbols of good stewardship and courageous steps toward sustainability. According to Don Aitken, a senior scientist with Union of Concerned Scientists, the number of birds killed so far is extremely small in relation to the number killed by other human activities that we have come to accept. Studies have shown that most avian deaths occur mainly in large wind farms in mountain passes. The number of trees that would need to be cut down to put up wind generators at SJU or CSB would be almost none since proposed sites already have access roads and are near cleared spaces.
Good training can reduce the risks from construction and maintenance to almost zero.
Energy's principal advantage over coal has always been the reduced risk to public health. Modern turbines operate quietly and considering that over 20,000 turbines have been installed worldwide, there have been very few complaints about noise. Turbines meet and exceed noise standards established even in densely populated countries like Denmark, where turbines operate close to residential zones. Additionally, wind turbine noise has not been observed to disturb wildlife. The swishing noise of a wind turbine at SJU or CSB could be compared to quiet music or conversation.