vvEPA
United States
Environmental Protection
Agency
High Radium Levels in
Anne Arundel County
Drinking Water Corrected
Partnerships and collaboration made
the difference
Background
In the late 1980's, high cancer death rates in
Anne Arundel County, Maryland were made a
health priority. Tobacco and other lifestyle issues
were targeted but concerns in the community
resulted in an Advisory Task Force to study
health and environmental factors to see if there
were other factors involved.
1995 Task Force
Charge:
1. Develop recommendations for control and
prevention of cancer;
2. Collect and maintain data about health
behaviors and environmental risks leading
to high cancer rates; and
3. Advise on ways to reduce cancer risk.
The Task Force included concerned citizens,
physicians, public health officers, scientists,
engineers, lawyers, and EPA officials. It
published its findings and recommendations
in 1996.
Conclusion:
Tobacco use, lack of medical screening,
and lack of proper diet and exercise were
major factors in cancer rates.
Not enough was known about air and
water pollutants to determine their role as
contributing factors.
Recommendation:
The task force recommended that the Anne
Arundel County Department of Health
(AADOH) investigate groundwater supplies
as little data was available about carcinogens
in private well water.
Figure 1. The dark green portion of Anne Arundel
County represents the testing area for gross alpha and
radium 226/228.
Pilot Study
As a result of the Task Force's recommendation,
AADOH and Anne Arundel County Department
of Public Works (AADPW), the Maryland
Geological Survey (MGS), and the U.S.
Geological Survey (USGS) conducted a
groundwater quality pilot study in 1997. The pilot
study included areas where groundwater was
vulnerable to carcinogens, including industrial and
commercial sites, areas with naturally occurring
radionuclides like radon, and agricultural areas
where pesticides were a potential contaminant.
Forty-seven domestic wells were tested for 43
contaminants: inorganic constituents including
iron and nitrate, radionuclides (uranium and
radium), volatile organic compounds (evaporating
chemicals such as benzene), and pesticides.
-------
Health Risk of
Radium
Consumption
EPA classifies radium-
226 and radium-228
as human carcinogens
(cancer-causing).
They are in a group of
carcinogens that have
the most severe effect
on humans and show
a causal relationship
to human bone cancer.
EPA's standard for the
maximum contaminant
level (MCL) for
combined radium-
226 and radium-228
in drinking water is
5 picocuries per liter
(pCi/L) - a measure of
radioactivity.
Radium enters the
body when it is
swallowed. If it is
ingested in water or
food, approximately
80% is voided
naturally; the other
20% enters the
bloodstream and
organs and migrates
to the bone. Radium-
226, once attached to
bone, remains in the
body for a person's
entire life. Adverse
health effects from
high levels of exposure
include bone and
skull cancers, anemia,
cataracts, fractured
teeth, bone tissue
breakdown, and death.
The additional lifetime
risk of cancer from
consuming drinking
water with 5 pCi/L of
radium is estimated at
about 1 in 10,000. As
radium concentration
increases, so does the
cancer risk.
Pilot Study Results
• For the majority of wells in the pilot study, no contaminants
exceeded the Safe Drinking Water Act's maximum contaminant level
(MCL).
• Arsenic above the MCL was detected in several samples.
• High concentration of radium was verified in three geological
formations: Magothy, Patapsco, and Patuxent aquifers (Figure 2).
• Radium-226 and radium-228 concentrations were detected at
rates above the MCL of 5.0 picocuries per liter (pCi/L) Fifteen
water samples in the Magothy and Patapsco Formations (northern
and central county) had radium concentrations that exceeded federal
drinking water standards.
200
I
I
-400
-400
Location of cross section
A
(lions are potentially
greater than the federal drinking water standards
Major aquifers in Anne Arundel County
Minor aquifers and non-water-bearing zones
Figure 2. Geological formations in northern Anne Arundel County.
Radium is naturally occurring; radium-contaminated groundwater
is the result of a natural hydrogeological process and possibly
compounded by human factors. Research has yet to determine how
radium contaminates groundwater; but, there is evidence from this
study that when an unconfined aquifer is acidic (pH levels less than 6),
radium is released from the aquifer materials into the groundwater in
Anne Arundel County. Radium is also released when the ground- water
contains high amounts of dissolved solids, particularly sodium and
chloride, which indicates that human activity may contribute to the
problem. Figure 2 (above) shows the locations in the aquifers where high
levels of radium occur in the groundwater, which range in depth from
the surface to about 100 feet below sea level. The highest level of radium
detected in the study was 66 pCi/L - over thirteen times the acceptable
level.
-------
Follow-Up
Although surveillance data indicated no increased level of bone cancer in the
affected area, the County had concerns for the potential for increased health risks.
County officials received the results of the pilot study and conferred with the
Maryland Department of the Environment (MDE). Because two of the aquifers
(Patapsco and Magothy) having high radium concentrations in the Anne Arundel
County study are used throughout the upper Chesapeake Bay area, MDE was
concerned that the problem may not be limited to Anne Arundel County. To
establish the full extent of contamination, MDE recommended expanding the
study into other areas in Maryland where the aquifers are used for drinking water.
The study expansion received financial support from EPA's Mid-Atlantic regional
office. The agencies worked together to survey and test the groundwater in this
area during 1998; 203 wells were sampled. High radioactivity in groundwater
was confirmed in northern and central Anne Arundel County, but generally not
found elsewhere. This suggested that the radium was localized within the shallow
groundwater of these aquifers.
About 49% of the 203 wells tested exceeded the MCL. Six of the wells in
the coastal plain that exceeded the MCL for gross alpha particles were not
in Anne Arundel County. By early 2000, AADOH had acquired significant
evidence that the aquifers that supply drinking water to approximately 20,000
residents in northern and central Anne Arundel County were contaminated.
Most homeowners were not exposed to high radium-levels since most radium-
contaminated wells were equipped with systems for iron removal, which
effectively reduces radium exposure to negligible levels.
The data revealed various patterns of high radium concentrations:
• Radioactivity was highest in the shallow unconfined parts of
the Coastal Plain aquifers.
• Radioactivity tended to be lower in deeper, confined aquifers;
in nearly all sampled wells deeper than 300 feet, radium
concentrations were below the MCL.
• Radioactivity tended to increase as the pH of the
groundwater decreased.
• Radium increased in direct proportion to increases in sodium
and chloride.
• Radium-224, which has a half-life of 3.64 days, appears to be
the dominant radium isotype.
Short Term Gross
Alpha Results
88
Ra
226.0254
Radium (Ra)
\ /
is the heaviest
alkaline
element; it occurs
• less than 5 pCi/L
O 5-15pCi/L
O 15.1-50pCi/L
• greater than 50 pCi/L
MCL for Gross Alpha is 15 pCi/L
Figure 3. Results of gross-alpha testing from wells in the Patapsco, Magothy,
and selected Piedmont aquifers.
naturally and is extremely
radioactive. Radium is
formed by uranium and
thorium decay. Three
isotopes of radium were
detected in Anne Arundel
County. Radium-224 is
not regulated in public
water supplies because
of its short half-life
(3.64 days); radium-226
has a half-life of 1,622
years and emits alpha
particles. Gross alpha
particle activity (GAPA)
is an indicator of the
amount of alpha-emitting
radionuclides, including
radium-224 and radium-
226.
Radium-228 has a
half-life of 5.75 years
and emits beta particles.
Gross beta-particle
activity (GBPA) is
an indicator of the
amount of beta-emitting
radionuclides, including
radium-228.
Radium isotopes are
found in soil, rocks,
plants, food, and
groundwater.
Water samples were
analyzed for both short
and long-term GAPA and
GBPA.
Short-term
measurements were
made within three days of
sample collection, while
long-term measurements
were made on the same
sample approximately
30 days after collection.
If the long-term GAPA is
much less than the short-
term GAPA, the decrease
is due to the rapid
decay of radium-224
or other alpha-emitting
radionuclides having
short half-lives.
-------
Management Implications
County health officials took steps to protect the local school system from radium in drinking
water supplies. Elevated radium levels were detected in the drinking well water in four County
schools. As an effective interim solution, bottled water was provided. All households of enrolled
students were notified, water treatment systems were installed and deeper wells were drilled (based
on evidence from the study) to ensure safe drinking water for all of the schools.
The County communicated the problem and its solutions to the public. Effective
communication was critical. The County launched a public information campaign to define the
problem and explain the options for safe mitigation.
The results of the scientific studies were
conveyed to the public. Residents whose
wells were sampled were alerted by mail.
The County issued press releases about the
findings after the presence of radium was
confirmed. Then, the new regulations for
well drilling went into effect.
Public outreach was conducted while
radium assessment continued. A radium
fact sheet was produced and continually
updated about radium, its effects, and
options for mitigation.
':; 3^*^.V\t»w
:
Figure 4. Measurements of water levels in ground-
water wells are needed to define the direction of
groundwater flow.
• Two open houses and 8 community meetings
were held at various schools to bring government
officials and the public together. The meetings
were advertised on radio, television, and in the
newspaper. Government and private experts
staffed stations to respond to residents' concerns.
By collaborating with other state and federal
agencies, AADOH was able to provide residents
with detailed and factual information. This public
forum had several advantages:
- Residents were able to obtain information
specific to their concerns. Tables were set up
for residents to receive radium information
from EPA, AADOH, the Board of Education,
doctors, and scientists.
- It provided a less formal environment that was
welcoming and not intimidating. Residents
could walk around the meeting place at
their own pace to learn about their specific
concerns.
- The open houses provided residents who
sought information an ample opportunity to
ask questions. This avoided the traditional
public meeting format, where it is easy for one
or two people's opinions to dominate and there
are few one-on-one interactions.
A mass mailing to about 20,000 residents alerted
them of the detection of radium and ways to
mitigate its effects. The County continues to offer
information to new homeowners about radium
mitigation. It requires all new wells to be tested for
radioactivity and radium.
-------
Solution
A short-term solution was developed to provide the affected area with safe drinking
water. MDE played a key role in developing a course of action. In 1998, MDE issued a
directive mandating new standards for new and replacement wells drilled in northern Anne
Arundel County. Wells constructed after June 1, 1998 were required to be tested for gross
alpha particles as a condition of the Certificate of Potability (COP). Where results were found
above the MCL, an effective treatment system was required. In addition, the property owner
was required to sign an agreement certifying that he or she is aware of the test results and
that the potability of the water supply is dependent upon proper maintenance of the treatment
system. The signed agreement was recorded against the deeds of the affected properties to
ensure future buyers were aware of the maintenance responsibilities.
AADOH and MDE then worked together to provide treatment options for homeowners who
elected not to replace wells immediately. Once the well water was found contaminated,
the homeowner had a choice of one of two recommended water treatment systems — ion
exchange or reverse osmosis.
ION EXCHANGE SYSTEM
REVERSE OSMOSIS SYSTEM
This is a point-of-use system where individual
faucets throughout the house are targeted and
filtered. It is a mechanical process that allows
some molecules to pass through a filter while
leaving others in the unit and is an economical
approach to providing safe drinking water.
This is a water softening system
capable of treating an entire
household's water supply. It is
typically used to decrease iron,
calcium, and magnesium deposits.
An ion exchange system tends to
produce excess sodium, so it may
not be appropriate for persons with
diet restrictions.
DISPENSING
FAUCET
-------
Long-term solution: AADOH, MGS, and MDE
also developed a database of radium samples. Nearly
2,000 samples were analyzed and catalogued. The
County and the State, with technical assistance from
EPA's Mid-Atlantic Integrated Assessment (MAIA)
program, developed a computerized three-dimensional
GIS (geographic information system) operating
model. Using radium samples as a data source, the
operating model indicates how deep a well must be
to avoid high radium levels. The County utilizes the
operating model to issue permits for the construction
of new and replacement wells.
Ninety-five percent of the new wells drilled to the
specified depth have radium concentrations below
the MCL (compared to 33% of the wells drilled prior
to minimum depth requirements).
Figure 5. Drilling new, deeper residential well.
The collection of
water samples for
analysis of trace
constituents such
as radiochemicals
requires consistent
methods and
equipment.
T
Figure 6. Technician in a vehicle specially equipped for the handling of water quality samples.
Most water quality
analyses can be
mf A~
done in the field.
Radiochemical
analysis needs to
be performed in a
laboratory.
Figure 7. Field analysis.
-------
Costs
Funding for various activities
was necessary. First, there were
studies to define the extent of
the problem (Figure 8). Second,
there was a collaborative
effort among scientists, public
health officers, and elected
officials to correct the problem.
Full-time staff were assigned
from MDE Water Management
Administration, USGS Water
Resources Program, MGS
Hydrogeology Division, and
AADOH Division of Community
and Environmental Health. EPA's
MAIA program developed a
3-D GIS computer model, based
on MGS's contours and 3-D
map to predict the occurrence
and location of the radium, and
trained the State and County to
use the model.
Other costs were associated
with testing individual private
wells for radioactivity. A
short-term gross alpha test
was used as a screening test
for high radium levels. The
gross alpha-particle test costs
$64. If the results are within
the acceptable range, no
further testing is necessary.
If the initial testing results
are between 5 and 15 pCi/L,
specific testing is necessary for
radium-226 and radium-228.
A test for combined levels of
radium-226 and radium-228
costs $158. Homeowners with
existing private wells typically
pay these testing expenses.
MDE and AADOH contributed
to the purchase of new
laboratory equipment (a low-
level automated Alpha-Beta
counter) to allow state testing
for short-term gross alpha
particles.
All mitigation options provided
safe, cost-effective drinking
water. These options were far
less expensive than extending
public water to all affected
areas. Anne Arundel County
estimated that it would cost
nearly $30,000 per household
and, even spread over 30
years, would be prohibitive for
many households. Therefore,
methods of mitigation at the
household level were deemed
more appropriate by the county
and state.
Cancer
Task Force, 1995
Carcinogenic
Pilot Study, 1997
Radium
Bay Area Study, 2000
GIS Maps Depth
and Alpha,2001
0 $50K $100 K $150 K $ 200 K $ 250 K
Figure 8. Radium assessment and mitigation study costs.
-------
j
55
®
xNNE
i ARUNDEL
M"A R Y L A N D
DEPARTMENT OF HEALTH
^USGS
science fora changing world
EPA Region 3
Philadelphia, PA 19103
EPA/903/F-04/005
July 2004
Patricia Bradley
bradley .patricia@epa. go v
410-305-2744
U.S. Environmental Protection Agency
Mid-Atlantic Integrated Assessment
Environmental Science Center
701 MapesRoad
Ft. Meade, MD 20755-5350
www. ep a. gov/maia
David W. Bolton
dbolton@dnr.state.md.us
410-554-5561
Maryland Geological Survey
Maryland Dept of Natural Resources
2300 St. Paul Street
Baltimore, MD 21218
www.mgs.md.gov
Kerry Topovski
hdkerryl@aacounty.org
410-222-7050
Anne Arundel County Dept of Health
Division of Community Environmental
Health
www. aahealth.org
John Grace
jgrace@mde. state.md.us
410-537-3714
Water Supply Program
Maryland Dept of the Environment
1800 Washington Blvd
Baltimore, MD 21230
www.mde.state.md.us
Thomas J. Vicino
tvicinol@umbc.edu
410-455-8662
University of Maryland, Baltimore County
Center for Urban Environmental Research
and Education
1000 Hilltop Circle - TRC 102
Baltimore, MD 21250
www.umbc.edu/cuere
Cherie V. Miller
cvmiller@usgs.gov
410-238-4254
U.S. Geological Survey
8987 Yellow Brick Road
Baltimore, MD 21237
www.usgs.gov
Printed on chlorine-free 100% recycled paper with
100% post-consumer fiber using vegetable-based ink.
MDE
UMBC
CUERE
Initiatives, Accomplishments & Results
• Proactive environmental management in the County
resulted in the creation of the Anne Arundel County
Advisory Cancer Task Force that led to the detection
of radium in the groundwater.
• Full scientific assessment was crucial. Two studies
determined the extent and distribution of radium
concentrations to provide the health risk assessment.
• Intergovernmental cooperation was a key to success.
Multiple agencies were involved in all stages of
assessment, mitigation, and public outreach:
- The County and State conducted comprehensive
health risk assessments of the danger of radium
consumption;
- The County and State worked together to determine
and communicate the degree of contamination;
- EPA's MAIAteam assisted with GIS expertise to
provide a mapping tool to help understand and
manage the radium contamination.
• Maintaining open channels of communication was
integral to sustaining the trust of the County's citizens:
- Early and full disclosure helped to establish trust
and develop rapport with the residents;
- Open-house meetings were a valuable mechanism
to convey information and interact with the
community;
- Residents' perception of risk needed to be
considered;
- Fear, emotion, or lack of interest was not allowed to
dictate mitigation strategies.
• A thorough knowledge of the nature of the problem
provided effective mitigation options.
• The solution had to balance risk and mitigation
options and consider various factors.
• Implementation of public policies and environmental
management practices provided for effective
prevention of a public health problem.
• Ninety-five percent of the new wells drilled to the
specified depth have radium concentrations below the
MCL.
MAIA Best Management Practices
Case Studies Course
Organizations throughout the Mid-Atlantic region have
developed and implemented unique approaches to respond
to environmental problems and concerns. The Mid-Atlantic
Integrated Assessment (MAIA) has also conducted
considerable research in the region, much of which has
been used by environmental managers to meet their
responsibilities.
MAIA and UMBC initiated a graduate-level research seminar
where students document these success stories so that other
managers and organizations can also use these approaches
and research.
------- |