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The U.S. Navy is proposing to deploy a system known as "Surveillance Towed Array Sensor System Low Frequency Active Sonar" (or LFA for short). Designed to "illuminate" enemy submarines with large amounts of acoustic noise, the system could have devastating impacts on marine mammals and other kinds of sea life. The Navy intends to deploy the LFA system in the deep oceans and along the coasts to protect aircraft carrier groups and supply routes from attack by quiet enemy submarines, despite the fact that such a threat has diminished greatly since the end of the Cold War. A prototype of the LFA system consists of 18 bathtub-size (approximately 180 feet in total length) transmitters designed to broadcast low-frequency, high-volume sound waves into the surrounding waters. Each transmitter can generate 215 decibels of sound, a level millions of times more intense than is considered safe for human divers. When the sound produced by all of these transmitters combine, the system's range is even greater. For example, by the Navy's own assessment during testing of the system in 1997, sound levels about 300 nautical miles from the source were estimated to peak at 140 dB. That is approximately 100 times more intense than levels of industrial noise known to cause behavioral disruptions in gray whales. At
its full deployment, LFA systems will periodically cover up to
80% of the world's oceans. Green Scissors Proposal Terminate the Navys Low Frequency Active Sonar Project. Current Status In March 2001, the National Marine Fisheries Service (NMFS) proposed to allow the Navy to deploy LFA and, in the process, to harass or injure marine mammals while flooding the ocean with intense noise. In response, the agency received tens of thousands of comment letters from scientists, conservation and animal welfare groups, members of Congress, and concerned citizens, virtually all in opposition to deployment. We can expect a final decision sometime in the next several months. Project Hurts Taxpayers LFA is designed to protect against a threat, specifically one from deep sea submarines, that has dramatically diminished since the end of the cold war. The Los Angeles Times reported on October 14, 1999 that taxpayers have already spent $350 million to build a defense system to detect threats from a non-existent submarine fleet, a sum that does not include the hundreds of millions already spent on building ships to house it. Project Hurts Environment LFA could have adverse impacts on entire populations of marine mammals. Marine mammals such as whales and dolphins rely on their hearing to locate food, find mates, avoid predators, navigate, and communicate. Yet, at even moderate intensities, the LFA signal has been shown to disrupt the communication, navigation, and breeding behavior of great whales. The long-term consequences of these widespread impacts are unknown. LFA could cause mass strandings of whales. On March 9, 2000, 17 whales from 4 different species were stranded in the Bahamas, and 8 whales died, a highly unusual event that coincided with the transit of sonar ships through the area. Autopsies of the dead whales pointed to death by high-intensity sound. It is important to note that such damage occurred while the surface ships and submarines involved were using "normal" mid-frequency military sonar. Given the extraordinary distances that low-frequency sound can travel underwater, the consequences of the LFA system are potentially much worse. LFA poses risks to human health. Divers participating in a Navy study were exposed to the LFA signal at moderate levels of intensity. On exposure to 136 decibels-a level of sound one could expect to hear hundreds of miles away from the LFA source-some divers began to experience what the Navy described as "beyond very severe aversion." One trained Navy diver who was exposed to 160 decibels reported feeling vertigo, memory dysfunction, and odd sensations in the chest and abdomen, and suffered a series of relapses over a period of months. Contacts
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