Thanks Greg--
We are probing the list of studies you came up with. Taken together,
the first six studies I've run through show measurable EMF impacts
with some potential themes lurking. I'll get back with a summary of
the studies for feedback. If anyone wants to help with the research,
contact me off list. I do think there a possible argument that
citizens might be able to use to effectively defend protected natural
areas. The developer that is proposing the 345 kV line here might
agree to funding a new study if the science is sound. Rob
At 8:39 AM -0700 3/21/11, Gregory O'Drobinak wrote:
>
>
>Rob:
>
>Good news about the Reserve Board!
>
>As for my attachment, it appears that this newsgroup stripped off my '.rtf=
'
>file. Is that normal for Yahoo newsgroups? However, I did send a
>personal email
>to you & Rich P., so you should have gotten that. In any case, I decided t=
o
>include the links at the end of this email so that everyone can look
>them over.
>
>I would think that trying to record underneath 345 KV lines, or even
>very close
>to them, would be difficult to do without picking up loads of hum. I would=
be
>surprised if any condenser mic could reject the strong electric field whic=
h
>could easily be 20 KV at 6 feet above the ground under said wires. I would=
be
>very careful when handling recording equipment under those wires and
>I would try
>to keep everything (cords & all!) at the same distance to ground level. Ma=
ybe
>having everything lying on the ground, micd included, would be the best wa=
y to
>try to record it.
>
>Sennheiser makes an optical mic that would not be affected by the
>strong electric field and the response goes up to 40KHz, but the self nois=
e is
>44dBA! Optimics has one that has lower self noise (31 dBA), but the freque=
ncy
>response is quite limited. So to faithfully record the acoustic sound clos=
e to
>the wires looks like a challenging problem. I'll see if I can find more in=
fo
>about this.
>
>Take care,
>
>Greg
>
>Effects on birds, wildlife and plants:
><http://audubon-omaha.org/bbbox/nabs/pdtg1.htm>http://audubon-omaha.org/bb=
box/nabs/pdtg1.htm
><http://www.wildlandscpr.org/node/211>http://www.wildlandscpr.org/node/211
><http://eng.hi138.com/?i42972>http://eng.hi138.com/?i42972
><http://scienceblogs.com/notrocketscience/2009/03/power_lines_disrupt_the_=
magnetic_alignment_of_cows_and_deer.php>http://scienceblogs.com/notrocketsc=
ience/2009/03/power_lines_disrupt_the_magnetic_alignment_of_cows_and_deer.p=
hp
>
>www.polarresearch.net/index.php/polar/article/download/6532/7365
><http://psc.wi.gov/thelibrary/publications/electric/electric10.pdf>http://=
psc.wi.gov/thelibrary/publications/electric/electric10.pdf
><http://www.academicjournals.org/AJB/PDF/pdf2010/27Sep/Demir.pdf>http://ww=
w.academicjournals.org/AJB/PDF/pdf2010/27Sep/Demir.pdf
><http://www.fas.org/ota/reports/8905.pdf>http://www.fas.org/ota/reports/89=
Message: 05.
Subject: pdf
><http://www.jstor.org/pss/2426995>http://www.jstor.org/pss/2426995
><http://www.savethelampasas.org/EK-%20Transmission%20line%20concerns.pdf>h=
ttp://www.savethelampasas.org/EK-%20Transmission%20line%20concerns.pdf
>
>EMF field plots (electric & magnetic) and Environmental Impact:
><http://www.emfs.info/Sources+of+EMFs/Overhead+power+lines/>http://www.emf=
s.info/Sources+of+EMFs/Overhead+power+lines/
><http://www.scribd.com/doc/25544985/Environmental-Impact-of-Transmission-L=
ines>http://www.scribd.com/doc/25544985/Environmental-Impact-of-Transmissio=
n-Lines
><http://efile.mpsc.state.mi.us/efile/docs/13934/0071.pdf>http://efile.mpsc=
.state.mi.us/efile/docs/13934/0071.pdf
><http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1637318/pdf/envhper00486-0143=
.pdf>http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1637318/pdf/envhper00486-0=
Message: 143.
Subject: pdf
><http://www.osmak.ae/featuredarticle.html#>http://www.osmak.ae/featuredart=
icle.html#
>
>Human Effects:
><http://siliconvalleyrealestateinfo.com/electric-and-magnetic-fields-emfs-=
and-how-they-effect-real-estate-prices.html>http://siliconvalleyrealestatei=
nfo.com/electric-and-magnetic-fields-emfs-and-how-they-effect-real-estate-p=
rices.html
>
><http://www.niehs.nih.gov/health/topics/agents/emf/>http://www.niehs.nih.g=
ov/health/topics/agents/emf/
><http://www.amazon.com/Electro-Magnetic-Field-Sper-Scientific/dp/B001EU9PQ=
0/ref=3Dwl_it_dp_oie=3DUTF8&coliid=3DI3DAR4XM4U9DKF&colid=3D3085QP7X1ZCF2>h=
ttp://www.amazon.com/Electro-Magnetic-Field-Sper-Scientific/dp/B001EU9PQ0/r=
ef=3Dwl_it_dp_oie=3DUTF8&coliid=3DI3DAR4XM4U9DKF&colid=3D3085QP7X1ZCF2
>
><http://www.epa.gov/radtown/power-lines.html>http://www.epa.gov/radtown/po=
wer-lines.html
><http://www.ehib.org/emf/longfactsheet.PDF>http://www.ehib.org/emf/longfac=
tsheet.PDF
><http://www.who.int/peh-emf/publications/sci_journal/en/index.html>http://=
www.who.int/peh-emf/publications/sci_journal/en/index.html
>
>________________________________
>From: Rob Danielson <<type%40uwm.edu>>
>To:
><naturerecordists%40yahoogroups.com>=
m
>Sent: Mon, March 21, 2011 4:08:30 AM
>Subject: Re: [Nature Recordists] Transmission Noise Pilot study
>
>Hi-
>Thanks for the helping me size-up the goals, everyone.
>
>Without my prodding, a member of the Reserve Board took a firm stand
>on potential negative sound impacts and opened the door. I think we
>can request a full scientific study if done right. I'm leaning
>towards a pilot study to demonstrate need. It could involve field
>calibration and then recording a 345 kV or larger transmission system
>at specified distances like .5 mile, 1500 ft; 900 ft; 600 ft, 300, ft
>and directly under the wires. Also some long duration, preferably
>simultaneous recordings maybe at 300 feet and 1500 ft. Best if done
>a few times at the same spots during spring migration, peak song bird
>nesting and fall migration. Are there other recordists who would be
>interested in participating? Of course, living within driving
>distance of 345 kV or larger transmission line passing through a
>fairly natural area is a must too.
>
>Greg, I could not access your High Voltage study attachment. Rob
>
>At 2:10 AM +0000 3/18/11, Avocet wrote:
>>
>>
>> > Using
>>>
>>><<http://www.sengpielaudio.com/calculator-air.htm>http://www.sengpielaud=
io.com/calculator-air.htm><http://www.sengpielaudio.com/calculator-air.htm>=
http://www.sengpielaudio.com/calculator-air.htm
>>>
>>>I get about 6dB loss
>>> per 100 feet. So assuming an additional drop in the noise of -12 db
>>> (-20 db total under background ambience) would still mask
>>> communications, we get 150' + 200' or 350 feet on both sides of the
>>> cables at 11 K hz.
>>
>>Rob,
>>
>>Yes, but they will shoot you down in flames of you don't include all
>>the variables. In addition you have the DB drop due to distance, which
>>is not quite inverse squared at 6dB per double the distance. At 30KHx
>>sengpiel gives -28dB at 100 feet plus distance loss, so the high
>>frequency response of audio mics is academic.
>>
>>Electromagnetic radiation is more important. This comes from corona
>>discharges especially in wet an icy weather. Electric companies will
>>quote warm and dry figures. In effect, the whole line is a giant radio
>>antenna which loses a percentage of the power it transmits (in
>>gigawatts).
>>
>>What effect does the alternaiing magnetic field have on birds which
>>use the Earth's magnetic field for navigation, like pigeons? I don't
>>know and I don't think anyone knows as the research hasn't been done.
>>
>>> condenser capsules mostly can
>>deliver dozens of khz. so you probably better use a microphone built
>>for measurement purposes.
>>
>>Or a bat detector as in my earlier message. Here's one, the songmeter:
>><<http://www.batecho.eu/html/frame18.html:>http://www.batecho.eu/html/fra=
me18.html:><http://www.batecho.eu/html/frame18.html:>http://www.batecho.eu/=
html/frame18.html:
>>
>>
>>> As for determining "public necessity" for the double circuit 345Kv
>>> line, our studies suggest so far that the high capacity project is
>>> not needed.
>>
>>The usual argument is that they are needed to "average out"
>>intermittent wind power, which is my anti campaign. This is adding
>>insult to injury after the turbines have chopped up large numbers of
>>bats and birds. Wind power is a highly visible "greenwash" with very
>>little overall benefit, but that's another campaign. I've always
> >maintained that nuclear energy is the answer. Don't try that one now.
>>:-) Of course the real solution is to stop extracting oil and gas but
>>I'm not putting any money on that one either.
>>
>>David
>>
>>David Brinicombe
>>North Devon, UK
>>Cogito cogito ergo cogito sum - Ambrose Bierce
>>
>>
>
>--
>
>
>
>
--
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