Following the catastrophic failure of two Vestas wind turbines on Feb 22 and 23, 2008, the Danish energy agency requested an investigation into the events. A report was produced by engineers at Risø DTU. Below is the report translated into English. The original report, in Danish, can be accessed by clicking on the link below. A video of one of the failures can be seen here: http://www.windaction.org/videos/14294 . It is important to note that the debris from the first turbine failure which occurred on February 22 spread as far as 700 meters away. Risø DTU is formerly a government research institution under the Danish Ministry of Science, Technology and Innovation.

This short GE Energy document explains the risk in the event of extreme wind conditions including hurricane or tornado and any mitigation. Note, the document acknowledges the risk of blade throws and tower collapse.

"Today, the task before the Joint Committee (regarding Bill S40) is to hear from the public on what would appear simple

- the giving and taking of “driveway” easements between the Commonwealth’s Wachusett Reservation (Stagecoach Trail) and the Town of Princeton’s legal “right of way” for its wind power site. As well, the town is offering the to transfer to the Commonwealth, ownership of, five acres of their 16-acre wind site.

I urge the Joint Committee for Bill S40 to carefully consider the following with regard to your recommendations an for easement exchange and accession of land from Princeton:

1. The Wachusett Wind Site is a 16 acre parcel wholly surrounded by the Wachusett Reservation and flanked within few feet, on three sides, by the well traveled Midstate, Harrington and Stagecoach trails. This portion of the state park is accessible and popular.

2. The present eight windmills are 120-feet high and are proposed to be replaced with two windmills as high as a 35- story building and with blades that stretch as wide as a football field - windmills whose elevation will come with 150- feet of the mountain’s elevation.

3. In the wintertime Wachusett experiences unusual ice storms in number and severity

4. In the wintertime, the windmills accumulate ice - then release it when it melts and falls, when it is blown off by wind or is thrown it off by the rotating blades

5. This ice has put holes in the roofs of utilty buildings on the wind farm and scattters itself across the fully accesssible wind site, the state reservation and hiking trails, threatening state park viisitors The risk associated with being struck windmill ice can be quantified and is relative to one’s distance from the windmills and will increase geometrically with the proposed windmills.

6. Windmills and wind data collection towers at Wachusett have structurally failed five times in twenty years on the Town of Princeton (PMLD) site. This also threatens the state park visitors as well with collapsing metal structures and flying blades. Proposed windmills and data towers will not be installed in compliance withthe manufacuturer’s recommendations and safety warnings."......

BBC Research & Consulting's 2005 report for the National Wind Coordinating Committee that studies 9 wind plant sitings in an effort to identify circumstances that distinguish welcomed projects from projects that were not accepted by communities.