RE: [Texascavers] San Saba County/CO2/radon

[George Veni]

As far as minerals go, uranium is relatively soluble and is not uncommon in
trace (non-hazardous) amounts in some groundwaters, and accumulates to
hazardous or potentially hazardous levels under certain conditions.

 

The link between radon and CO2 in caves is currently tenuous at best; they
both accumulate where there is less air circulation, but it is not yet
certain they have a similar origin. A lot of work remains to be done on both
topics. CO2 can be from deep sources, decomposition of organic material,
poor air circulation, and other factors. I've observed that caves in the
Austin Chalk (think of Robber Baron Cave) and Ellenberger Limestone (think
of Colorado Bend) have the highest CO2 in the state, and both are
oil-producing units where they are buried deep underground. That suggests to
me that they contain higher levels of organic carbon which is possibly being
released as the limestone is dissolved in the outcrops and shallow
subsurface where we know caves occur. Then again, there could be some other
reason and I may be completely wrong. What is needed is a set of analyses of
the carbon isotopes in the CO2 in various high CO2 caves of central Texas.
Those results will eliminate some possible sources and will likely point
strongly to other sources.

 

Someone pointed out earlier that the underlying granite in the Colorado Bend
area is an unlikely source of CO2. I agree. For Gill and others interested
in the hydrogeology of the area, download
http://www.twdb.state.tx.us/publications/reports/GroundWaterReports/GWReport
s/R346/R346.pdf (this is about a 10 Mb file) and look at Figures 4-7 which
are geologic cross sections of the area. For other reports on Texas
hydrogeology, check out
http://www.twdb.state.tx.us/publications/reports/GroundWaterReports/GWReport
s/GWreports.asp. Don't be too disappointed if you see little or no
karst-specific information on the reports on Texas' karst aquifers.
Historically, karst has not been considered much although it has been
getting more and long overdue attention in the past 10 years. 

 

George

 

 

From: cavera...@aol.com [mailto:cavera...@aol.com] 
Sent: Wednesday, December 22, 2010 13:52
To: texascavers@texascavers.com
Subject: Re: [Texascavers] San Saba County/CO2/radon

 

 

I'm interested in seeing a cross-section of the
sequence--including ground water conditions) above the granite (also
known to have radiation levels above EPA MCLs). 

Gill's prompts me to ask: anybody know where in hell the uranium and radon
in Houston's water comes from?  We aren't exactly known for our igneous (or
any other) rock exposures.

Roger again.

 

-Original Message-
From: Gill Edigar 
To: Aimee Beveridge 
Cc: Cavers Texas 
Sent: Wed, Dec 22, 2010 1:48 pm
Subject: Re: [Texascavers] San Saba County/CO2/radon

OK. But I'm interested in seeing a cross-section of the
sequence--including ground water conditions) above the granite (also
known to have radiation levels above EPA MCLs). That granite is pretty
hot, as I understand it, and decomposition of it could be producing a
lot of CO2 & radon. I don't think there would be much geothermal
influence left in the pluton but don't really know that and is one of
the questions I'm looking for somebody to answer. Also, was that area
not part of the Llano Uplift? If not, it is very near it. The caves of
that area have always had a CO2 content higher than other Texas caves
and which would seem to me to be unjustified by the decay of organic
surface material--especially since some caves don't take run off but
still have a lot of CO2.
 

[Texascavers] San Saba Radon/CO2

[rafal kedzierski]

Or coexistence of radon and CO2 in caves of Ellenburger limestone could 
indicate that the limestone is poorly permeable and simply doesn't allow for 
good ventilation of gases produced below the surface. Radon is a product of 
U-234 to thorium to radium to finally radon, with alpha particle decay (two 
protons and two neutrons) and no release of chemical such as CO2 as byproduct. 
Heating of limestone at high temperatures produces CO2 - but that would have to 
be in excess of 800C (and even higher at higher pressures) - temperature that 
is not attained until depth of 30+ km is reached.  Therefore, this is not 
likely to have an effect on local aquifers.

Rafal Kedzierski
  

[Texascavers] Fatal cave accident in Sótano de Ahuihuitzcapa, México

[Antonio AA]

Yesterday, a tourist fell inside the pit entrance of Sótano de Ahuihuitzcapa 
(180mt deep pit). As I know at this moment, he was not a caver. He was just 
watching the pit entrance when the accident happens. This cave is in Zongolica 
area in the state of Veracruz. Espeleo Rescate México team from Veracruz were 
alerted today and they went to the cave and confirmed the death. Recovery 
maneuvers will be held tomorrow morning. There will be more information as soon 
we get it.

Sherppa   

[Texascavers] New Bat Species

[Mark Minton]

A new species of bat from New 
Guinea: 
.


Mark Minton

Please reply to mmin...@caver.net
Permanent email address is mmin...@illinoisalumni.org 



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Re: [Texascavers] Re: San Saba County/CO2/radon

[Bill Bentley]

Well at least all we have here is hexavalent chromium in our groundwater

http://www.cbsnews.com/stories/2009/06/10/earlyshow/main5076625.shtml

:(

Bill
- Original Message - 
From: "Mark Minton" 

To: 
Sent: Wednesday, December 22, 2010 5:00 PM
Subject: [Texascavers] Re: San Saba County/CO2/radon


Decomposition of granite would not produce any significant amount 
of CO2 on its own.  Granite is mostly silica and alumina and contains very 
little carbonate.  Maybe the heat from radioactivity in granite could bake 
CO2 out of overlying limestone, though.


Mark Minton

At 02:48 PM 12/22/2010, Gill Edigar wrote:

OK. But I'm interested in seeing a cross-section of the
sequence--including ground water conditions) above the granite (also
known to have radiation levels above EPA MCLs). That granite is pretty
hot, as I understand it, and decomposition of it could be producing a
lot of CO2 & radon. I don't think there would be much geothermal
influence left in the pluton but don't really know that and is one of
the questions I'm looking for somebody to answer. Also, was that area
not part of the Llano Uplift? If not, it is very near it. The caves of
that area have always had a CO2 content higher than other Texas caves
and which would seem to me to be unjustified by the decay of organic
surface material--especially since some caves don't take run off but
still have a lot of CO2.
--Ediger

On Wed, Dec 22, 2010 at 1:25 PM, Aimee Beveridge  wrote:
> Gill,
>
> I'd bet that San Saba caves could could have slightly higher radon than
> background, especially if they are connected to groundwater enriched in
> radon and have little air turnover.  Radon gas is denser than air.
>
> You'd need long term exposure for it to be a health risk. Living
in a poorly
> ventilated house with a water well producing from igneous, metamorphic 
> or
> coal or hcarb-bearing strata would be of much greater concern 
> naturally.

>
> Most of Texas (including San Saba), has very low radon gas compared to 
> many
> other parts of the country.  Risk increases over the Llano Uplift and 
> El

> Paso area.  See map.
>
> http://www.city-data.com/radon-zones/Texas/Texas.html
>
> The ash layers (bentonite beds) in our local Austin Chalk are somewhat
> radioative.  Recent studies of groundwater from Houston have shown 
> elevated
> levels (above EPA MCLs) of uranium and radium.  Tangentially, no level 
> of
> radioativity is really safe but avoiding cigarretts, air travel and 
> x-ray

> machines is helpful.
>
> Aimee
> 
> From: Gill Edigar 
> To: Cavers Texas 
> Sent: Tue, December 21, 2010 5:18:05 PM
> Subject: [Texascavers] San Saba County/CO2/radon
>
> For a long time after I first visited caves in San Saba County in the
> 1960s I assumed that the source of the high levels of CO2 were due to
> decomposition of organic materials that originated on the surface. At
> some point (years ago) after radon became a hot topic I started
> associating radon with CO2 out gassing and more recently wondering if
> any radon studies have been done at CBSP. So I asked my caver friend
> and geologist Steve Hall of Virginia about those relationships. He is
> a radon specialist. He said that the source of out gassing CO2 is
> often igneous rocks which are also a radon source. I started to wonder
> what the rock sequence was in the Gorman Falls area. How thick is the
> limestone/dolomite? What formations lay between the top layer and the
> granite below? Could that be a source for the CO2? Should cavers there
> take any special precautions regarding radon? I tried the internet
> without getting much satisfaction so am wondering if anybody has
> information on any of that handy. It would make an interesting
> discussion.
> --Ediger


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[Texascavers] Re: San Saba County/CO2/radon

[Mark Minton]

Decomposition of granite would not produce any significant 
amount of CO2 on its own.  Granite is mostly silica and alumina and 
contains very little carbonate.  Maybe the heat from radioactivity in 
granite could bake CO2 out of overlying limestone, though.


Mark Minton

At 02:48 PM 12/22/2010, Gill Edigar wrote:

OK. But I'm interested in seeing a cross-section of the
sequence--including ground water conditions) above the granite (also
known to have radiation levels above EPA MCLs). That granite is pretty
hot, as I understand it, and decomposition of it could be producing a
lot of CO2 & radon. I don't think there would be much geothermal
influence left in the pluton but don't really know that and is one of
the questions I'm looking for somebody to answer. Also, was that area
not part of the Llano Uplift? If not, it is very near it. The caves of
that area have always had a CO2 content higher than other Texas caves
and which would seem to me to be unjustified by the decay of organic
surface material--especially since some caves don't take run off but
still have a lot of CO2.
--Ediger

On Wed, Dec 22, 2010 at 1:25 PM, Aimee Beveridge  wrote:
> Gill,
>
> I'd bet that San Saba caves could could have slightly higher radon than
> background, especially if they are connected to groundwater enriched in
> radon and have little air turnover.  Radon gas is denser than air.
>
> You'd need long term exposure for it to be a health risk. Living 
in a poorly

> ventilated house with a water well producing from igneous, metamorphic or
> coal or hcarb-bearing strata would be of much greater concern naturally.
>
> Most of Texas (including San Saba), has very low radon gas compared to many
> other parts of the country.  Risk increases over the Llano Uplift and El
> Paso area.  See map.
>
> http://www.city-data.com/radon-zones/Texas/Texas.html
>
> The ash layers (bentonite beds) in our local Austin Chalk are somewhat
> radioative.  Recent studies of groundwater from Houston have shown elevated
> levels (above EPA MCLs) of uranium and radium.  Tangentially, no level of
> radioativity is really safe but avoiding cigarretts, air travel and x-ray
> machines is helpful.
>
> Aimee
> 
> From: Gill Edigar 
> To: Cavers Texas 
> Sent: Tue, December 21, 2010 5:18:05 PM
> Subject: [Texascavers] San Saba County/CO2/radon
>
> For a long time after I first visited caves in San Saba County in the
> 1960s I assumed that the source of the high levels of CO2 were due to
> decomposition of organic materials that originated on the surface. At
> some point (years ago) after radon became a hot topic I started
> associating radon with CO2 out gassing and more recently wondering if
> any radon studies have been done at CBSP. So I asked my caver friend
> and geologist Steve Hall of Virginia about those relationships. He is
> a radon specialist. He said that the source of out gassing CO2 is
> often igneous rocks which are also a radon source. I started to wonder
> what the rock sequence was in the Gorman Falls area. How thick is the
> limestone/dolomite? What formations lay between the top layer and the
> granite below? Could that be a source for the CO2? Should cavers there
> take any special precautions regarding radon? I tried the internet
> without getting much satisfaction so am wondering if anybody has
> information on any of that handy. It would make an interesting
> discussion.
> --Ediger


Please reply to mmin...@caver.net
Permanent email address is mmin...@illinoisalumni.org 



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RE: [Texascavers] San Saba County/CO2/radon

[Susie Giles]

I live in San Saba Co and you might be interested in the Annual Drinking
Water Quality Reports for the Richland SUD (Special Utility District) which
is required public info.  The Radium levels are high but my understanding
(which could be wrong) is that there is no state or federal guidelines for
levels of Combined Radium or Gross Beta emitters for water supplies.  The
reported source of Contaminant is "Erosion of Natural Deposits" and "Decay
of natural and Man-made deposits" respectively.  We have been assured by a
chemist that Clark works with that the RO water softener we have installed
at our home takes care of these risks and that the risk is in the steam from
heated water.  Doesn't seem like that would affect cavers?  Not many geysers
around here -= just old geezers.
Respectfully and Happy Holidays,
Susie Giles


-Original Message-
From: bgillegi...@gmail.com [mailto:bgillegi...@gmail.com] On Behalf Of Gill
Edigar
Sent: Wednesday, December 22, 2010 1:48 PM
To: Aimee Beveridge
Cc: Cavers Texas
Subject: Re: [Texascavers] San Saba County/CO2/radon

OK. But I'm interested in seeing a cross-section of the
sequence--including ground water conditions) above the granite (also
known to have radiation levels above EPA MCLs). That granite is pretty
hot, as I understand it, and decomposition of it could be producing a
lot of CO2 & radon. I don't think there would be much geothermal
influence left in the pluton but don't really know that and is one of
the questions I'm looking for somebody to answer. Also, was that area
not part of the Llano Uplift? If not, it is very near it. The caves of
that area have always had a CO2 content higher than other Texas caves
and which would seem to me to be unjustified by the decay of organic
surface material--especially since some caves don't take run off but
still have a lot of CO2.
--Ediger

On Wed, Dec 22, 2010 at 1:25 PM, Aimee Beveridge  wrote:
> Gill,
>
> I'd bet that San Saba caves could could have slightly higher radon than
> background, especially if they are connected to groundwater enriched in
> radon and have little air turnover.  Radon gas is denser than air.
>
> You'd need long term exposure for it to be a health risk. Living in a
poorly
> ventilated house with a water well producing from igneous, metamorphic or
> coal or hcarb-bearing strata would be of much greater concern naturally.
>
> Most of Texas (including San Saba), has very low radon gas compared to
many
> other parts of the country.  Risk increases over the Llano Uplift and El
> Paso area.  See map.
>
> http://www.city-data.com/radon-zones/Texas/Texas.html
>
> The ash layers (bentonite beds) in our local Austin Chalk are somewhat
> radioative.  Recent studies of groundwater from Houston have shown
elevated
> levels (above EPA MCLs) of uranium and radium.  Tangentially, no level of
> radioativity is really safe but avoiding cigarretts, air travel and x-ray
> machines is helpful.
>
> Aimee
> 
> From: Gill Edigar 
> To: Cavers Texas 
> Sent: Tue, December 21, 2010 5:18:05 PM
> Subject: [Texascavers] San Saba County/CO2/radon
>
> For a long time after I first visited caves in San Saba County in the
> 1960s I assumed that the source of the high levels of CO2 were due to
> decomposition of organic materials that originated on the surface. At
> some point (years ago) after radon became a hot topic I started
> associating radon with CO2 out gassing and more recently wondering if
> any radon studies have been done at CBSP. So I asked my caver friend
> and geologist Steve Hall of Virginia about those relationships. He is
> a radon specialist. He said that the source of out gassing CO2 is
> often igneous rocks which are also a radon source. I started to wonder
> what the rock sequence was in the Gorman Falls area. How thick is the
> limestone/dolomite? What formations lay between the top layer and the
> granite below? Could that be a source for the CO2? Should cavers there
> take any special precautions regarding radon? I tried the internet
> without getting much satisfaction so am wondering if anybody has
> information on any of that handy. It would make an interesting
> discussion.
> --Ediger
>
> -
> Visit our website: http://texascavers.com
> To unsubscribe, e-mail: texascavers-unsubscr...@texascavers.com
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>
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Fwd: [Texascavers] CO2 and radon

[Diana Tomchick]

>
> I don't know where you get your statistics on lung cancer, but they're off 
> base and misleading. According to the World Health Organization 
> (http://www.who.int/tobacco/research/cancer/en/):
>
> "Lung cancer - the big one"
> As noted at the outset, the paper describing the association between tobacco 
> use and lung cancer stands as a classic in public health. On average, smokers 
> increase their risk of lung cancer between 5 and 10-fold and in developed 
> countries, smoking is responsible for upwards of 80% of all lung cancers. 
> Using American data, 24% of men who smoke can expect to developing cancer 
> during their expected life time.
>
> Lung cancer remains a disease with a dismal prognosis. Although one-year 
> all-stage survival is reported to have increased from 32% in 1973 to 41% in 
> 1994, five-year survival has remained unchanged at 14%. Early detection has 
> been promoted as a potentially valuable intervention but its 
> cost-effectiveness puts it beyond the reach of all but the most wealthy 
> health care systems, and even then, pales in comparison to the 
> cost-effectiveness of comprehensive programs and policies to reduce tobacco 
> consumption.
> --
>
> The 24% statistic quoted above is for all cancers (and there are many more 
> than just lung) associated with tobacco use. According to the National Cancer 
> Institute (statistics for 2005-2007), the lifetime risk (percent) of lung 
> cancer for all races and both sexes for all people (smokers and non-smokers) 
> is 6.95%. For perspective, the rate for all types of cancers is about 41%. 
> (BTW, as you get past the age of about 50, your roughly twice as likely to 
> die of cancer or heart disease than you are to die of Alzheimer's disease). 
> See 
> http://seer.cancer.gov/csr/1975_2007/results_single/sect_01_table.14_2pgs.pdf 
> for more details.
>

I can't help but follow-up on these statistics with some back-of-the-envelope 
calculations.

If we assume that smoking increases your lung cancer lifetime risk five-fold 
over non-smokers, and roughly 20% of Americans smoked in 2007 (see 
http://www.webmd.com/smoking-cessation/news/20081113/smoking-rate-is-declining-in-us),
 then the lung cancer lifetime risk is:

Non-smokers = 3.9%
Smokers = 19.3%

If we assume that instead smoking increases your lung cancer lifetime risk 
ten-fold over non-smokers, then the lung cancer lifetime risk is:

Non-smokers = 2.5%
Smokers = 25%

So the 24% quoted on the WHO page is actually probably just for lung cancer 
(since the overall lifetime risk of all cancers is about 41% for the whole 
population), and the rate for non-smokers is clearly higher than 1%.

According to the EPA (http://www.epa.gov/radon/healthrisks.html), radon is 
indeed the leading cause of lung cancer among non-smokers, being responsible 
for about 21,000 deaths per year. By contrast, second-hand smoke, which so many 
more people worry about, is estimated to cause only 3,000 deaths per year among 
non-smokers. Second-hand smoke is of more concern to people with asthma and 
chronic obstructive pulmonary disorder, though.

The synergistic effects of smoking and radon exposure have been noted and can 
also increase a person's lung cancer lifetime risk.

Diana

* * * * * * * * * * * * * * * * * * * * * * * * * * * *
Diana R. Tomchick
Associate Professor
University of Texas Southwestern Medical Center
Department of Biochemistry
5323 Harry Hines Blvd.
Rm. ND10.214B
Dallas, TX 75390-8816, U.S.A.
Email: diana.tomch...@utsouthwestern.edu
214-645-6383 (phone)
214-645-6353 (fax)




UT Southwestern Medical Center
The future of medicine, today.

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Re: [Texascavers] San Saba County/CO2/radon

[caverarch]

I'm interested in seeing a cross-section of the
sequence--including ground water conditions) above the granite (also
known to have radiation levels above EPA MCLs). 

Gill's prompts me to ask: anybody know where in hell the uranium and radon in 
Houston's water comes from?  We aren't exactly known for our igneous (or any 
other) rock exposures.


Roger again.





-Original Message-
From: Gill Edigar 
To: Aimee Beveridge 
Cc: Cavers Texas 
Sent: Wed, Dec 22, 2010 1:48 pm
Subject: Re: [Texascavers] San Saba County/CO2/radon


OK. But I'm interested in seeing a cross-section of the
sequence--including ground water conditions) above the granite (also
known to have radiation levels above EPA MCLs). That granite is pretty
hot, as I understand it, and decomposition of it could be producing a
lot of CO2 & radon. I don't think there would be much geothermal
influence left in the pluton but don't really know that and is one of
the questions I'm looking for somebody to answer. Also, was that area
not part of the Llano Uplift? If not, it is very near it. The caves of
that area have always had a CO2 content higher than other Texas caves
and which would seem to me to be unjustified by the decay of organic
surface material--especially since some caves don't take run off but
still have a lot of CO2.


 

texascavers Digest 22 Dec 2010 20:49:13 -0000 Issue 1214

[texascavers-digest-help]

texascavers Digest 22 Dec 2010 20:49:13 - Issue 1214

Topics (messages 16747 through 16763):

TPWD Commission Approves Devils River Land Acquisition
16747 by: Logan McNatt

Re: 9:00 CDT tonight:  "World's Biggest Cave" on National Geographic channel
16748 by: John P Brooks

"Lost World" blog on NY TIMES website
16749 by: John P Brooks

party Dec 29
16750 by: Mixon Bill
16751 by: Mark.Alman.L-3com.com

San Saba County/CO2/radon
16752 by: Gill Edigar
16760 by: Aimee Beveridge
16761 by: Gill Edigar
16762 by: tbsamsel.verizon.net
16763 by: caverarch.aol.com

New pictures of the Martian pits
16753 by: Marvin & Lisa
16755 by: Geary Schindel

Photo gallery of LARGE Vietnam cave
16754 by: Scott Boyd
16757 by: Mark.Alman.L-3com.com
16758 by: Karen

CO2 and radon
16756 by: Mixon Bill
16759 by: Diana Tomchick

Administrivia:

To subscribe to the digest, e-mail:


To unsubscribe from the digest, e-mail:


To post to the list, e-mail:



--
--- Begin Message ---


Great news!  Yesterday the TPWD Commissioners approved the purchase of the Devils River Ranch property.  All 13 people who requested to speak (3 
minutes each) were in favor of the purchase, and most of them thanked TPWD for listening to the public's complaints and finding a way to keep 
the current Devils River SNA.  Arron Wertheim spoke on behalf of TCMA and cavers.


Here's the link to the announcement on the TPWD website:

http://www.tpwd.state.tx.us/newsmedia/releases/?req=20101220b

Logan
--- End Message ---
--- Begin Message ---
This show is replaying on Monday, December 27th at 5 pm

Plenty of time to hit those post Christmas sales and buy a BIG screen TV.


--- On Mon, 12/20/10, Logan McNatt  wrote:

From: Logan McNatt 
Subject: [Texascavers] 9:00 CDT tonight:  "World's Biggest Cave" on National 
Geographic channel
To: "Texascavers" 
List-Post: texascavers@texascavers.com
Date: Monday, December 20, 2010, 8:06 PM

A reminder that the NG channel has a show on the "World's Biggest Cave" in one 
hour:  tonight at 9:00 pm.
Unfortunately, I don't have a wide-screen TV; the images may not fit on my 
small old TV.

Logan

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--- End Message ---
--- Begin Message ---
http://scientistatwork.blogs.nytimes.com/2010/12/17/following-maps-and-finding-a-lost-world/?ref=science

This is an interesting BLOG on the NY Times website, posted by a expedition in 
Madagascar. In this and other posts; they have visited quite a few caves. They 
don't have a TV show requiring a big TV...but each blog is an interesting read.
--- End Message ---
--- Begin Message ---
I'm having a party at my house the evening of Wednesday, December 29,  
my 70th birthday. Sevenish till it's over. Cake, some munchies, wimpy  
yellow beer, and cheap wine provided. Bring whatever else, or just  
yourself. 14045 North Green Hills Loop, Austin, Texas 78737 (actually  
in northern Hays County). (512) 288-4991 (Austin phone).


As of this writing, the idiot Google map on the UT Grotto calendar is  
incorrect. My house is about 150 yards east of where they show it to be.


Directions: Green Hills Loop, marked only by a small red street sign,  
takes off from RR 1826 4.8 miles left of where the far south end of  
Mopac expressway (Loop 1, then Tx 45) T's into it, or 2.3 miles right  
of where 967 from Buda T's into it. From the north (Mopac), it is  
about 200 yards past a fire station. From the south (967), it is  
across the road from a fire-station warning sign. On Green Hills Loop,  
go right at the Y, steeply uphill. At the top of the hill are two  
large houses (not mine), and the road turns left along the ridgetop.  
Do not turn left, but go straight ahead onto my driveway. There is  
lots of parking on what passes for my lawn, but late-comers might need  
to park along the road on the way up the hill.


I have put a good map at amcs-pubs.org/mixon.gif. -- Bill Mixon

A fearless man cannot be brave.

You may "reply" to the address this message
came from, but for long-term use, save:
Personal: bmi...@alumni.uchicago.edu
AMCS: edi...@amcs-pubs.org or sa...@amcs-pubs.org

--- End Message ---
--- Begin Message ---
We won't be able to make it, Bill, as my wife and I will be in N'
Awlins, celebrating our anniversary.

But, HAPPY 70th, Bill!



Mark



-Original Message-
From: Mixon Bill [mailto:bmixon...@austin.rr.com] 
Sent: Tuesday, December 21, 2010 10:14 AM
To: Cavers Texas
Subject: [Texascavers] party Dec 29

I'm having a party at my house the 

Re: [Texascavers] San Saba County/CO2/radon

[caverarch]

How comforting to us Houstonians!  But we are in the midst of transitioning 
from groundwater to surface water for the region, I assume more due to concern 
over subsidence than uranium or radon content.  One natural component of our 
groundwater that will be missed if it isn't replaced artificially is flouride.  
Kids from the parts of town with natural fluoridation have grown up with much 
more intact dentition.  (Concern of threats to precious bodily fluids per Gen. 
'Buck' Turgidson aside.)


Roger





-Original Message-
From: Aimee Beveridge 
To: Gill Edigar ; Cavers Texas 
Sent: Wed, Dec 22, 2010 1:25 pm
Subject: Re: [Texascavers] San Saba County/CO2/radon



Gill,
 
I'd bet that San Saba caves could could have slightly higher radon than 
background, especially if they are connected to groundwater enriched in radon 
and have little air turnover.  Radon gas is denser than air.  
 
You'd need long term exposure for it to be a health risk. Living in a poorly 
ventilated house with a water well producing from igneous, metamorphic or coal 
or hcarb-bearing strata would be of much greater concern naturally.  
 
Most of Texas (including San Saba), has very low radon gas compared to many 
other parts of the country.  Risk increases over the Llano Uplift and El Paso 
area.  See map. 
 
http://www.city-data.com/radon-zones/Texas/Texas.html
 
The ash layers (bentonite beds) in our local Austin Chalk are somewhat 
radioative.  Recent studies of groundwater from Houston have shown elevated 
levels (above EPA MCLs) of uranium and radium.  Tangentially, no level of 
radioativity is really safe but avoiding cigarretts, air travel and x-ray 
machines is helpful.  
 
Aimee



From: Gill Edigar 
To: Cavers Texas 
Sent: Tue, December 21, 2010 5:18:05 PM
Subject: [Texascavers] San Saba County/CO2/radon

For a long time after I first visited caves in San Saba County in the
1960s I assumed that the source of the high levels of CO2 were due to
decomposition of organic materials that originated on the surface. At
some point (years ago) after radon became a hot topic I started
associating radon with CO2 out gassing and more recently wondering if
any radon studies have been done at CBSP. So I asked my caver friend
and geologist Steve Hall of Virginia about those relationships. He is
a radon specialist. He said that the source of out gassing CO2 is
often igneous rocks which are also a radon source. I started to wonder
what the rock sequence was in the Gorman Falls area. How thick is the
limestone/dolomite? What formations lay between the top layer and the
granite below? Could that be a source for the CO2? Should cavers there
take any special precautions regarding radon? I tried the internet
without getting much satisfaction so am wondering if anybody has
information on any of that handy. It would make an interesting
discussion.
--Ediger

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Re: Re: [Texascavers] San Saba County/CO2/radon

[tbsamsel]

Have you checked w. BEG?Dec 22, 2010 01:48:11 PM, gi...@att.net wrote:OK. But I'm interested in seeing a cross-section of thesequence--including ground water conditions) above the granite (alsoknown to have radiation levels above EPA MCLs). That granite is prettyhot, as I understand it, and decomposition of it could be producing alot of CO2 & radon. I don't think there would be much geothermalinfluence left in the pluton but don't really know that and is one ofthe questions I'm looking for somebody to answer. Also, was that areanot part of the Llano Uplift? If not, it is very near it. The caves ofthat area have always had a CO2 content higher than other Texas cavesand which would seem to me to be unjustified by the decay of organicsurface material--especially since some caves don't take run off butstill have a lot of CO2.--EdigerOn Wed, Dec 22, 2010 at 1:25 PM, Aimee Beveridge  wrote:> Gill,>> I'd bet that San Saba caves could could have slightly higher radon than> background, especially if they are connected to groundwater enriched in> radon and have little air turnover.  Radon gas is denser than air.>> You'd need long term exposure for it to be a health risk. Living in a poorly> ventilated house with a water well producing from igneous, metamorphic or> coal or hcarb-bearing strata would be of much greater concern naturally.>> Most of Texas (including San Saba), has very low radon gas compared to many> other parts of the country.  Risk increases over the Llano Uplift and El> Paso area.  See map.>> http://www.city-data.com/radon-zones/Texas/Texas.html>> The ash layers (bentonite beds) in our local Austin Chalk are somewhat> radioative.  Recent studies of groundwater from Houston have shown elevated> levels (above EPA MCLs) of uranium and radium.  Tangentially, no level of> radioativity is really safe but avoiding cigarretts, air travel and x-ray> machines is helpful.>> Aimee> > From: Gill Edigar > To: Cavers Texas > Sent: Tue, December 21, 2010 5:18:05 PM> Subject: [Texascavers] San Saba County/CO2/radon>> For a long time after I first visited caves in San Saba County in the> 1960s I assumed that the source of the high levels of CO2 were due to> decomposition of organic materials that originated on the surface. At> some point (years ago) after radon became a hot topic I started> associating radon with CO2 out gassing and more recently wondering if> any radon studies have been done at CBSP. So I asked my caver friend> and geologist Steve Hall of Virginia about those relationships. He is> a radon specialist. He said that the source of out gassing CO2 is> often igneous rocks which are also a radon source. I started to wonder> what the rock sequence was in the Gorman Falls area. How thick is the> limestone/dolomite? What formations lay between the top layer and the> granite below? Could that be a source for the CO2? Should cavers there> take any special precautions regarding radon? I tried the internet> without getting much satisfaction so am wondering if anybody has> information on any of that handy. It would make an interesting> discussion.> --Ediger>> -> Visit our website: http://texascavers.com> To unsubscribe, e-mail: texascavers-unsubscr...@texascavers.com> For additional commands, e-mail: texascavers-h...@texascavers.com>>>-Visit our website: http://texascavers.comTo unsubscribe, e-mail: texascavers-unsubscr...@texascavers.comFor additional commands, e-mail: texascavers-h...@texascavers.com

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Re: [Texascavers] San Saba County/CO2/radon

[Gill Edigar]

OK. But I'm interested in seeing a cross-section of the
sequence--including ground water conditions) above the granite (also
known to have radiation levels above EPA MCLs). That granite is pretty
hot, as I understand it, and decomposition of it could be producing a
lot of CO2 & radon. I don't think there would be much geothermal
influence left in the pluton but don't really know that and is one of
the questions I'm looking for somebody to answer. Also, was that area
not part of the Llano Uplift? If not, it is very near it. The caves of
that area have always had a CO2 content higher than other Texas caves
and which would seem to me to be unjustified by the decay of organic
surface material--especially since some caves don't take run off but
still have a lot of CO2.
--Ediger

On Wed, Dec 22, 2010 at 1:25 PM, Aimee Beveridge  wrote:
> Gill,
>
> I'd bet that San Saba caves could could have slightly higher radon than
> background, especially if they are connected to groundwater enriched in
> radon and have little air turnover.  Radon gas is denser than air.
>
> You'd need long term exposure for it to be a health risk. Living in a poorly
> ventilated house with a water well producing from igneous, metamorphic or
> coal or hcarb-bearing strata would be of much greater concern naturally.
>
> Most of Texas (including San Saba), has very low radon gas compared to many
> other parts of the country.  Risk increases over the Llano Uplift and El
> Paso area.  See map.
>
> http://www.city-data.com/radon-zones/Texas/Texas.html
>
> The ash layers (bentonite beds) in our local Austin Chalk are somewhat
> radioative.  Recent studies of groundwater from Houston have shown elevated
> levels (above EPA MCLs) of uranium and radium.  Tangentially, no level of
> radioativity is really safe but avoiding cigarretts, air travel and x-ray
> machines is helpful.
>
> Aimee
> 
> From: Gill Edigar 
> To: Cavers Texas 
> Sent: Tue, December 21, 2010 5:18:05 PM
> Subject: [Texascavers] San Saba County/CO2/radon
>
> For a long time after I first visited caves in San Saba County in the
> 1960s I assumed that the source of the high levels of CO2 were due to
> decomposition of organic materials that originated on the surface. At
> some point (years ago) after radon became a hot topic I started
> associating radon with CO2 out gassing and more recently wondering if
> any radon studies have been done at CBSP. So I asked my caver friend
> and geologist Steve Hall of Virginia about those relationships. He is
> a radon specialist. He said that the source of out gassing CO2 is
> often igneous rocks which are also a radon source. I started to wonder
> what the rock sequence was in the Gorman Falls area. How thick is the
> limestone/dolomite? What formations lay between the top layer and the
> granite below? Could that be a source for the CO2? Should cavers there
> take any special precautions regarding radon? I tried the internet
> without getting much satisfaction so am wondering if anybody has
> information on any of that handy. It would make an interesting
> discussion.
> --Ediger
>
> -
> Visit our website: http://texascavers.com
> To unsubscribe, e-mail: texascavers-unsubscr...@texascavers.com
> For additional commands, e-mail: texascavers-h...@texascavers.com
>
>
>

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Re: [Texascavers] San Saba County/CO2/radon

[Aimee Beveridge]

Gill,

I'd bet that San Saba caves could could have slightly higher radon than 
background, especially if they are connected to groundwater enriched in radon 
and have little air turnover.  Radon gas is denser than air.  


You'd need long term exposure for it to be a health risk. Living in a poorly 
ventilated house with a water well producing from igneous, metamorphic or coal 
or hcarb-bearing strata would be of much greater concern naturally.  


Most of Texas (including San Saba), has very low radon gas compared to many 
other parts of the country.  Risk increases over the Llano Uplift and El Paso 
area.  See map. 


http://www.city-data.com/radon-zones/Texas/Texas.html

The ash layers (bentonite beds) in our local Austin Chalk are somewhat 
radioative.  Recent studies of groundwater from Houston have shown elevated 
levels (above EPA MCLs) of uranium and radium.  Tangentially, no level of 
radioativity is really safe but avoiding cigarretts, air travel and x-ray 
machines is helpful.  

Aimee



From: Gill Edigar 
To: Cavers Texas 
Sent: Tue, December 21, 2010 5:18:05 PM
Subject: [Texascavers] San Saba County/CO2/radon

For a long time after I first visited caves in San Saba County in the
1960s I assumed that the source of the high levels of CO2 were due to
decomposition of organic materials that originated on the surface. At
some point (years ago) after radon became a hot topic I started
associating radon with CO2 out gassing and more recently wondering if
any radon studies have been done at CBSP. So I asked my caver friend
and geologist Steve Hall of Virginia about those relationships. He is
a radon specialist. He said that the source of out gassing CO2 is
often igneous rocks which are also a radon source. I started to wonder
what the rock sequence was in the Gorman Falls area. How thick is the
limestone/dolomite? What formations lay between the top layer and the
granite below? Could that be a source for the CO2? Should cavers there
take any special precautions regarding radon? I tried the internet
without getting much satisfaction so am wondering if anybody has
information on any of that handy. It would make an interesting
discussion.
--Ediger

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Re: [Texascavers] CO2 and radon

[Diana Tomchick]

>  Stay out of old uranium mines. The radon risk was first observed in uranium 
> miners who smoked. The management agency for Horsethief Cave, Wyoming, used 
> to keep track of the radon exposure of cavers to whom they'd given permits; 
> there was a reasonable amount of uranium in some of the fill in the cave. 
> Don't know whether they're still doing that or not. But the government 
> worries about anything that will increase your lifetime risk of getting lung 
> cancer by a few percent relatively, when it's only about 1% anyway if you 
> haven't smoked a lot. That is, from, say, 1% up to 1.1%. Big deal. Some 
> show-cave guides might have enough exposure to radon to worry about. Radon is 
> thought to be the greatest cause of lung cancer in non-smokers, but it's 
> still a very rare disease in non-smokers. (Contrary to what one might think 
> from all the propaganda, the chance of even a smoker getting lung cancer 
> during his lifetime is not more than 10 percent.) -- Mixon

Bill,

I don't know where you get your statistics on lung cancer, but they're off base 
and misleading. According to the World Health Organization 
(http://www.who.int/tobacco/research/cancer/en/):

"Lung cancer - the big one"
As noted at the outset, the paper describing the association between tobacco 
use and lung cancer stands as a classic in public health. On average, smokers 
increase their risk of lung cancer between 5 and 10-fold and in developed 
countries, smoking is responsible for upwards of 80% of all lung cancers. Using 
American data, 24% of men who smoke can expect to developing cancer during 
their expected life time.

Lung cancer remains a disease with a dismal prognosis. Although one-year 
all-stage survival is reported to have increased from 32% in 1973 to 41% in 
1994, five-year survival has remained unchanged at 14%. Early detection has 
been promoted as a potentially valuable intervention but its cost-effectiveness 
puts it beyond the reach of all but the most wealthy health care systems, and 
even then, pales in comparison to the cost-effectiveness of comprehensive 
programs and policies to reduce tobacco consumption.
--

The 24% statistic quoted above is for all cancers (and there are many more than 
just lung) associated with tobacco use. According to the National Cancer 
Institute (statistics for 2005-2007), the lifetime risk (percent) of lung 
cancer for all races and both sexes for all people (smokers and non-smokers) is 
6.95%. For perspective, the rate for all types of cancers is about 41%. (BTW, 
as you get past the age of about 50, your roughly twice as likely to die of 
cancer or heart disease than you are to die of Alzheimer's disease). See 
http://seer.cancer.gov/csr/1975_2007/results_single/sect_01_table.14_2pgs.pdf 
for more details.

Also from the National Cancer Institute:

"Definition of lung cancer: Cancer that forms in tissues of the lung, usually 
in the cells lining air passages. The two main types are small cell lung cancer 
and non-small cell lung cancer. These types are diagnosed based on how the 
cells look under a microscope.



UT Southwestern Medical Center
The future of medicine, today.

Estimated new cases and deaths from lung cancer (non-small cell and small cell 
combined) in the United States in 2010:


 New cases: 222,520
 Deaths: 157,300

The three leading causes of cancer death for all men, with the exception of 
Asian/Pacific Islanders, were lung, prostate and colorectal cancer. Lung, liver 
and colorectal cancers were the top three causes of cancer death in 
Asian/Pacific Islander men. For women, the three leading causes of cancer death 
were lung, breast and colorectal cancer for all racial/ethnic groups except 
Hispanic women, for whom breast cancer ranked first."

Get your facts straight the next time you pontificate about something you 
clearly know little about, such as health issues. Lung cancer is serious and 
few people who get it survive for long, and the side effects of treatment 
aren't pretty. And we're not even talking about the other common cancers of 
smokers such as oral, throat and stomach cancer, which are also extremely 
common and quite nasty.

Diana

* * * * * * * * * * * * * * * * * * * * * * * * * * * *
Diana R. Tomchick
Associate Professor
University of Texas Southwestern Medical Center
Department of Biochemistry
5323 Harry Hines Blvd.
Rm. ND10.214B   
Dallas, TX 75390-8816, U.S.A. 
Email: diana.tomch...@utsouthwestern.edu
214-645-6383 (phone)
214-645-6353 (fax)
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Re: [Texascavers] Photo gallery of LARGE Vietnam cave

[Karen]

Agreed, it is breathtaking.  Thanks for the link, Scott.

Cheers,
Karen

On Wed, Dec 22, 2010 at 11:05 AM,  wrote:

>
>
> If you like HUGE caves, like I do, this one looks perfect!
>
>
>
> Wow! I may need to take a trip to Vietnam sometime.
>
>
>
> (Why can’t we have more caves like this in Texas?! I thought the ones we
> visited in NM were huge, but, not like this one).
>
>
>
>
>
>
>
> Mark
>
>
>
>
>
>
>
>
>
> *From:* Scott Boyd [mailto:sdboy...@yahoo.com]
> *Sent:* Tuesday, December 21, 2010 7:43 PM
> *To:* Texascavers@texascavers.com
> *Subject:* [Texascavers] Photo gallery of LARGE Vietnam cave
>
>
>
> If you like cave photos, here's a photo gallery of a large cave in Vietnam:
>
> http://ngm.nationalgeographic.com/2011/01/largest-cave/peter-photography
>
> Scott
>
>
>

RE: [Texascavers] Photo gallery of LARGE Vietnam cave

[Mark . Alman]

 

If you like HUGE caves, like I do, this one looks perfect!

 

Wow! I may need to take a trip to Vietnam sometime.

 

(Why can't we have more caves like this in Texas?! I thought the ones we
visited in NM were huge, but, not like this one).

 

 

 

Mark

 

 

 

 

From: Scott Boyd [mailto:sdboy...@yahoo.com] 
Sent: Tuesday, December 21, 2010 7:43 PM
To: Texascavers@texascavers.com
Subject: [Texascavers] Photo gallery of LARGE Vietnam cave

 

If you like cave photos, here's a photo gallery of a large cave in
Vietnam:

http://ngm.nationalgeographic.com/2011/01/largest-cave/peter-photography

Scott

 

[Texascavers] CO2 and radon

[Mixon Bill]

Some people are a lot more qualified to answer Ediger's questions than  
I am, but seeing as none of them has jumped in


CO2 of volcanic origin in pretty rare in caves. Main sources are decay  
of organic matter and oxidation of material in the bedrock, the former  
more often than the latter. (The decay of organic matter might not be  
occurring in the cave. Soil CO2 can be carried in drips or stream  
water.) But I understand that there is a relatively large amount of  
petroleum in the limestone in which the caves around San Saba have  
formed, so that might be a reason "bad air" is so often present there  
compared to a lot of other places. I doubt if the limestone around  
there contains much uranium, the source of radon, but there might be  
some in deeper rocks.


Anyway, CO2 accumulations are a sign of poor ventilation, and that is  
the same circumstance that would allow radon to accumulate, if there  
were any of it seeping from the rock. However, the radon hazard in  
caves has for twenty years or so been generally overhyped every time  
it is "rediscovered." I doubt if there are any circumstances under  
which recreational cavers, at least non-smokers, need to worry about  
it in any natural caves. Stay out of old uranium mines. The radon risk  
was first observed in uranium miners who smoked. The management agency  
for Horsethief Cave, Wyoming, used to keep track of the radon exposure  
of cavers to whom they'd given permits; there was a reasonable amount  
of uranium in some of the fill in the cave. Don't know whether they're  
still doing that or not. But the government worries about anything  
that will increase your lifetime risk of getting lung cancer by a few  
percent relatively, when it's only about 1% anyway if you haven't  
smoked a lot. That is, from, say, 1% up to 1.1%. Big deal. Some show- 
cave guides might have enough exposure to radon to worry about. Radon  
is thought to be the greatest cause of lung cancer in non-smokers, but  
it's still a very rare disease in non-smokers. (Contrary to what one  
might think from all the propaganda, the chance of even a smoker  
getting lung cancer during his lifetime is not more than 10 percent.)  
-- Mixon


Incidentally, the accumulation of CO2 in the lower part of a cave has  
nothing to do with the fact that it's heavier than air. (I don't  
remember the exact numbers, but to get a doubling--nowhere near what  
we call bad air--of CO2 just because of its molecular weight, you'd  
need a pit full of completely still air thousands of meters deep.)  
When it accumulates deep in a cave, it's just being created or  
released there faster than it is removed by diffusion or air  
movements. -- Mixon


A fearless man cannot be brave.

You may "reply" to the address this message
came from, but for long-term use, save:
Personal: bmi...@alumni.uchicago.edu
AMCS: edi...@amcs-pubs.org or sa...@amcs-pubs.org


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RE: [Texascavers] New pictures of the Martian pits

[Geary Schindel]

Very nice,

Thanks,

Geary

From: Marvin & Lisa [mailto:mlmil...@gvtc.com]
Sent: Tuesday, December 21, 2010 6:21 PM
To: texascavers@texascavers.com
Subject: [Texascavers] New pictures of the Martian pits

http://news.nationalgeographic.com/news/2010/12/photogalleries/101221-mars-pits-pictures-photos-science-nasa-space-caves/#/mars-pits-overview_30639_600x450.jpg