EPA/EERF-MANUAL-78-1
R
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in Water Sampling
Program
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The Eastern Environmental Radiation Facility(EERF) is a
field facility of the U.S. Environmental Protection
Agency's Office of Radiation Programs(ORP).
Copies of this manual may be obtained by direct
request to the EERF. To request copies of the manual, or
for additional information concerning the procedures
described herein, write to:
Eastern Environmental Radiation Facility
P.O. Box 3009
Montgomery, Alabama 36109
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CONTENTS
I. Background 1
II. Sampling Program 2
A. Selection of Sampling Site 2
B. Sampling Kits 2
C. Sample Collection 2
D. Sample Data Form 10
E. Sample Log 10
F Return of Samples to EERF 10
List of Figures
Figure 1. Radon in water - sampling kit 3
Figure 2. Radon sampling kit - close-up 4
Figure 3. Connect tube to water supply 5
Figure 4. Allow water to slowly collect in funnel 6
Figure 5. Withdrawing water sample with syringe 7
Figure 6. Eject air bubbles and excess water 8
Figure 7. Inject sample into sample vial 9
Figure 8. Sample data form 11
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I. Background
Radon-222 is an inert, noble gas and
a radioactive decay product of radium-
226. Radon diffuses through the
underground geological strata and into
underground aquifers and surface
waters. These waters may also contain
radium-226, but there does not appear to
be a direct correlation between radium-
226 and radon-222 concentrations.
Radon exists in ground water at
concentrations which are typically
much greater than its immediate
precursor, radium-226. This most likely
occurs because radium-226 is trapped in
the rocks, sands and clays which make
up the aquifers while radon, as a noble
gas, is much freer to migrate into the
water.
Radon in drinking water has
previously been considered a source of
radiation exposure primarily from an
ingestion standpoint. However, the
Office of Radiation Programs (ORP) of
the Environmental Protection Agency
(EPA) is investigating radon in water
supplies because of the possibility thata
major pathway from inhalation exposure
may exist, in addition to the ingestion
pathway.
Previously, studies associated with
the inhalation of radon were limited to
miners and the mining industry,
primarily the uranium mining industry.
In 1970, the EPA assumed responsibility
from the United States Public Health
Service (PHS) for the investigation of
radon and radon daughter exposures
resulting from the use of uranium mill
tailings. Since that time additional work
has investigated radon exposures from
natural gas, phosphate mining and
milling practices, and the burning of
coal in power plants.
Measurements of radon in water in
the U.S. have been recorded as early as
1905, when abnormally high
concentrations were found in the spring
water of Hot Springs National Park,
Arkansas. Since that time there have
been numerous reports in the literature
indicating radon-222 concentrations in
selected water supplies in excess of
2,000 pCi/l. Specific geographic areas
shown to have such high concentration
include Maine, North Carolina, Texas,
Arkansas, Florida, and Utah.
Dose estimates in the literature are
generally based on radon progeny
ingested with the water. However, more
recent data indicates that inhalation of
radon and radon progeny may produce
significantly higher exposures. As an
inert gas, radon is not chemically bound
to the water and, consequently, can be
released during any operation that
aerates or agitates water. Measurements
of radon releases from water in the home
during clothes washing, dishwashing,
showers, etc., demonstrated emanation
percentages from 70 to 100 percent
depending on the temperature of the
water and the amount of agitation.
In addition to the release of radon in
homes, large quantities of radon could
be released in water treatment plants or
by large industrial users of water. Water
treatment plants that employ aeration,
or industrial users who use water for
spraying, cooling, etc., could be
potential sources for radon released to
the environment.
To determine the scope of this
potential problem, a national sampling
program is necessary to obtain data on
radon in public and private water
samples across the country. A suitable
sampling kit has been developed by the
Eastern Environmental Radiation
Facility (EERF)) to collect water samples
from many locations throughout the
U.S. The kit is designed so that samples
can be collected from any potable water
supply and shipped, without loss of
radon other than radioactive decay, to
EERF for analysis.
The water samples will be collected,
using a syringe, and added to a liquid
scintillation vial containing a
premeasured amount of liquid
scintillation mix. The samples will be
returned to EERF for analysis using a
liquid scintillation counter. A mineral oil
based liquid scintillation mix has been
chosen to allow mailing of samples.
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Sampling Program
A. Selection of Sampling Site
If special instructions are not given,
the routine selection of a sampling site
can be any location where the water is
routinely used. This source can be any
faucet that is easily accessible, e.g., an
outside faucet at a service station, etc.
B. Sampling Kits (figures 1 and 2) are
small lightweight carrying cases
complete with all materials necessary
for collecting potable water samples for
radon-222 analysis. Each kit contains
the following equipment:
1 sampling funnel and tube
with standard faucet fitting
1 - slip-on faucet adapter
2 - 20 ml syringes
2 18 gauge
hypodermic needles
two-inch
20 to 30 glass scintillation
vials with 10 ml solution each
C. Sample Collection
1. Attach the sampling funnel
and tube to a faucet with either the
standard faucet fitting or adapter
(figure 3).
2. Slowly turn on the water and
allow a steady stream to flow out of
the funnel for approximately 2
minutes. This purges the tube and
assures a fresh sample.
3. Reduce the flow of water and
invert the funnel (figure 4). The flow
should be adjusted to a level that
does pot cause turbulence in the
pool of water contained in the
funnel. Allow excess water to spill
over one edge of the funnel.
4. Examine the hose connection
and tubing for air bubbles or
pockets. If these are visible, raise or
lower the funnel until they are
removed.
5. Place the tip of the
hypodermic needle approximately
3 cm under the surface of the water
in the funnel and withdraw a few ml
of water and eject this water. Using
this procedure, rinse the syringe
and hypodermic needle two or three
times.
6. Again, place the tip of the
needle approximately 3 cm below
the surface of the water and
withdraw 12 to 15 ml (figure 5).
NOTE: The water should be pulled
Into the syringe slowly to avoid
extreme turbulence and collection
of air bubbles. If large air bubbles
are noticed In the syringe, the
sample should be ejected and
redrawn.
7. Invert the syringe and slowly
eject any small air bubbles and
extra water (figure 6). Retain
precisely 10 ml of water in the
syringe.
8. Remove the cap from a vial and
carefully place the tip of the needle
into the bottom of- the liquid
scintillation solution (figure 7).
Slowly eject the water from the
syringe into the vial. NOTE: The
water Is Infected under the liquid
scintillation solution to prevent loss
of radon from the sample. If the
water Is forced out of the syringe
with much pressure, It will cause
turbulence In the solution and could
result In loss of radon.
9. Carefully withdraw the
hypodermic needle from the vial
and replace the cap. The cap should
be tightly secured to prevent
leakage.
10. Repeat the previous steps to
obtain two separate samples from
each source. This completes the
sample collection.
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Figure 1. Radon In water - sampling kit.
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Figure 2. Radon sampling kit - close-up.
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-^ -•»
Figure 3. Connect tube to water supply.
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Figure 4. Allow water to slowly collect In funnel.
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Figure 5. Withdrawing water sample with syringe.
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Figure 6. Eject air bubbles and excess water.
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Figure 7. Inject sample Into sample vial.
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D. Sample Data Form •- Figure 8.
Provide the following information on the
form:
1. Date that the sample is
'collected, e.g., 3/10/78.
2. Time of collection
indicate the time of day that the
sample was collected, e.g., 9:35
A.M. CST.
3. Sample numbers-the cap
for each vial is prenumbered.
Record this number for each
sample collected at a site.
4. Location - identify the
sampling location with as much
detail as possible, e.g., street
address, city, county, state, etc.
5. Description of Source - if
the water source is a private well,
mark the appropriate box and
indicate the depth if known. If the
source of water is a public
(municipal) supply, then mark that
box and indicate if it originates from
groundwater wells (give depth, if
available) or surface supplies.
Provide any additional information
concerning the water source that is
available. Particularly useful
information includes water
treatment processes, aeration,
chemical additives, etc.
6. Sample Collected By -
provide the name, address, and
phone number of the person who
collects the samples.
E. Sample Log - A separate log
containing the above information
should be kept with the sample kit as
backup data in the event of loss of the
sample data form.
F. Return of Samples to EERF -
After collection of the samples, they
will be mailed to the EERF for analysis.
Each liquid scintillation vial should be
individually wrapped with the absorbent
material provided and placed in the self-
addressed mailing tubes (two vials and
the data form per tube). These mailing
tubes will be provided by EERF separate
from the sampling kit. The two samples
from each source should be packaged
and mailed as soon as possible. Due to
the short half-life of radon-222 (3.8
days), the quick return of the samples for
analysis is of primary importance.
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Sample No.'s:
Date:
Time of Collection:
Location:
Description of Source: D Private Well (Depth )
D Public Supply
D Groundwater (Well Depth )
or D Surface Water (Lake, Reservoir, etc.)
Additional Information:
Sample collected by: Name.
Address-
Phone
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