What is the range of specific conductance of drinking water in homes
and businesses the USA? |
Request for Question Clarification by
pafalafa-ga
on
17 Apr 2005 16:31 PDT
dnovot-ga,
Can you tell us a bit more about the type of answer you are expecting.
The specific conductance of water is measured in units of
micro-Siemens per centimer (uS/cm), and its value for drinking water
is generally below 750 uS/cm. In some saline groundwater sources,
values can go as high as 70-80,000 uS/cm, but this is obviously well
beyond the range of drinking water.
So...do you just want documentation that the upper limit in drinking
water is about 750 uS/cm? Or are you looking for some other sort of
information on this topic?
Let me know, please.
pafalafa-ga
|
Clarification of Question by
dnovot-ga
on
18 Apr 2005 18:28 PDT
Clarifiying question answer: I am particularly interested in the
LOWEST conductivity levels water treatment companies maintain in each
of the 50 states with authoritative evidence (treatment plant water
quality specifications or reports on measurements). I believe the USGS
has data (some where )on underground water supplies in each state
(above ground water is rarely used as a drinking water source).
Ranges, both high and low for each state would be an acceptable answer
with accompanying support data (reports on measurements, or levels
water treatment plants subcribe to). I am not interested in areas that
get potable water from desalinization plants as these conductivities
are around 30 microS. I expect the lowest conductivity numbers will be
from resivoirs filled from snow/ice packs in the region. Are these
snow pack derived reseviors 50 microS or 70 microS or higher or lower
typically. What does the data show?
Thank you,
Please ask any other questions you may have.
dnovot-ga
|
Request for Question Clarification by
pafalafa-ga
on
18 Apr 2005 19:51 PDT
dnovot-ga,
Thanks for getting back to me...your clarification was a real help.
I am not aware of a comprehensive national database that compiles data
on specific conductance from all states, nor have I found any in
searches of EPA, USGS, and other likely sources.
There are a smattering of reports that show up from an ordinary Google
search. From a quick overview, I would say only a handful of states
are represented in the results. But some of the information that is
available is fairly comprehensive. Here's a small excerpt from an
aquifer in Georgia:
-----
EPD sampled four wells drawing from the Providence aquifer system in calendar
year 2002. Two wells, GWN-PD2B and GWN-PD5, are situated in the recharge area,
whereas wells GWN-PD3 and GWN-PD6 tap confined portions of the aquifer.
Conductivity data are available for three of the wells and range from
42 uS/cm to 390 uS/cm.
-----
As you can see, there's quite a range in the conductivity, with
measurements ranging almost an order of magnitude.
At other aquifers in the state, measurements as high as 900+ uS/cm, or
as low as in the teens were recorded, so the range out there -- in
this one state -- is pretty substantial.
I'm not sure I can do more than compile the results from the scattered
reportes that I've found. But again, this would fall far short of a
comprehensive picture of conductivity values in all 50 states.
Let me know your thoughts as to what makes sense at this point.
pafalafa-ga
|
Request for Question Clarification by
pafalafa-ga
on
07 May 2005 06:42 PDT
Hello dnovot-ga,
Just checking in...Do you have any more thoughts you can offer about
the information I've presented thus far?
Thanks,
pafalafa-ga
|
