Project Sanguine Project Sanguine was a U . S . Navy project , proposed in 1968 and only implemented in a more limited form , to create a hardened extremely low frequency ( ELF ) radio transmitter facility in Wisconsin to communicate with deeply submerged submarines . The originally proposed system would have a giant " antenna " consisting of 6000 miles of buried cables in a rectangular grid covering 22 , 500 square miles , 40 % of the state of Wisconsin , powered by 100 underground power plants in concrete bunkers . The cables were grounded at their ends , and loops of AC electric current flowed deep in the ground between the ends of the cable , generating ELF waves . The original design was projected to cost billions and consume 800 megawatts of power . The goal was a system that could transmit tactical orders one - way to U . S . nuclear submarines anywhere in the world , and survive a direct nuclear attack . The project was controversial from the start and was attacked by politicians , antiwar and environmental groups concerned about the effects of high ground currents and electromagnetic fields on the environment . The nuclear survivability of the system was made doubtful by Soviet development of MIRV ballistic missiles . After an attempt to resite the project in the Llano Uplift of Texas was also stopped by public opposition , the Navy abandoned Sanguine and proposed a series of increasingly modest variants : Project Seafarer ( 1975 ) , Austere ELF ( 1978 ) , and finally Project ELF ( 1981 ) , which was constructed . The system became operational in 1989 , and was used until 2004 , when it became obsolete and was shut down . Project ELF . The scaled - down system the Navy eventually constructed , called Project ELF , began testing in 1982 and became operational in 1989 . It consisted of two transmitter facilities , one at Clam Lake , Wisconsin and one at Republic , Michigan . with a total of 84 miles of above - ground transmission line antenna . The two transmitters normally operated synchronized together as one antenna for greater range , but could also operate independently . The scaled down system was not designed to survive a nuclear attack . The Clam Lake facility , which served as the test site and was originally called the Wisconsin Test Facility ( WTF ) consisted of two 14 - mile ( 24 km ) transmission line antennas ( called ground dipole s ) in the shape of a cross , with the transmitter station at their intersection . The Republic facility consisted of three transmission lines , two 14 - mile and one 28 - mile , in the shape of the letter " F " ( the shape is not significant and was dictated by land availability ) . The lines , made of 1 . 5 cm aluminum cable supported on insulators on 40 ft . wooden utility poles , resembled ordinary power transmission lines . The ends of the transmission lines were grounded by 1 to 3 miles of buried copper cable and ground rods , later replaced by arrays of electrodes in deep 300 ft . boreholes The transmitters sent alternating currents of 300 amperes through the lines , which passed through the buried electrodes deep into the Earth . The transmitters operated at a frequency of 76 Hz in the extremely low frequency band , with an alternate capability at 45 Hz and used a combined power of 2 . 6 megawatts . They were able to communicate with submarines over about half the world ' s surface . The system transmitted continuously , 24 hours a day , sending an " idle " message when it was not being used . Because of the extremely small bandwidth of the ELF band , the transmitters had a very slow data rate . They couldn ' t transmit voice ( audio ) but only short coded text messages of a few letters . Reportedly it took 15 minutes to transmit a single 3 letter code group . Therefore the system was not used to relay operational orders , but served a " bell - ringer " function , ordering specific submarines to the surface to receive detailed orders by ordinary radio and satellite communications links . The system was controversial , and was the target of legal attacks , suits and protests throughout its operating life . On five occasions protesters cut down transmission line poles , interrupting operation briefly . In 2004 the Navy shut down both transmitters , with the explanation that very low frequency ( VLF ) communication systems had improved to the point that the ELF system was unnecessary . How ELF communication works . Submarines are shielded by seawater from all ordinary radio signals , and therefore are cut off from communication with military command authorities while submerged . The lower the frequency , the deeper radio waves are able to penetrate ocean water . Waves in the very low frequency ( VLF ) range of 3 kHz to 30 kHz are able to penetrate to a depth of about 10 to 30 meters , and since WWII navies have used VLF transmitters to communicate with submarines . To receive VLF signals subs must rise to just under the surface or trail a shallow antenna buoy , making them vulnerable to detection by the enemy . Radio waves in the extremely low frequency ( ELF ) band of 30 to 300 Hz can penetrate to a depth of hundreds of meters , allowing them to communicate with submarines at their normal operating depth . The lower the frequency , the longer the wavelength of the radio waves , and transmitters require longer antenna structures to generate them . ELF transmitters use huge antennas called ground dipole s consisting of tens to hundreds of kilometers of overhead cables resembling ordinary power transmission lines . The transmission lines are ground ed at the ends , and looping currents deep in the Earth form part of the antenna . ELF transmitters are most efficient when sited over certain low resistivity underground rock formations , which allow the currents to spread deeper forming a larger " antenna " . The US system was located in Wisconsin and the Upper Peninsula of Michigan over the Laurentian Shield formation , for that reason . Such ELF transmitters cannot be installed on submarines , because of the size of the antenna and high power requirements . So ELF communication is one - way , with a receiver in the submarine receiving orders from a shore station , but unable to reply . The low attenuation of ELF waves with distance allows a single ELF station to send messages to submarines all over the world . Another drawback of ELF is that the ELF band has very small bandwidth , and therefore can only transmit very simple messages , very slowly . ELF signals cannot carry audio ( voice ) like other types of radio , and can only carry short text messages consisting of a few letters . The US Navy system ( above ) reportedly uses three - letter code groups and requires 15 minutes to transmit one group . So current systems are not used to transmit detailed orders , but serve a " bell ringer " function , to order a specific vessel to surface and receive further orders by ordinary radio or satellite communication . The US and Russia are the only nations known to have constructed ELF communication facilities . The Russian Navy reportedly operates an ELF transmitter , ZEVS , located northwest of Murmansk on the Kola Peninsula in northern Russia .