research
development
www.epa.gov/ord
FACT SHEET
EPA's Water Treatment Demonstration Project to Reduce
Amount of Arsenic in Stewart, MN, Drinking Water
Researchers from EPA's National Risk Management
Research Laboratory (NRMRL), headquartered in
Cincinnati, Ohio, are working in partnership with
Stewart, MD, and a contractor to install and operate a
water treatment technology aimed at reducing the level
of arsenic in local drinking water. Operation of the
demonstration project began in January, 2006,
and is being regularly monitored to determine progress.
Background
Arsenic is a naturally occurring contaminant found in
ground water in various locations throughout the United States. Research and development
efforts at EPA have identified certain technologies that remove arsenic from drinking water.
Some community water systems often face challenges in choosing the right technology to
reduce the level of arsenic. Therefore, in select demonstration projects across the country,
just like this one in Stewart, EPA is partnering with municipalities and equipment producers
to bring the most appropriate drinking water technology into the field and demonstrate their
effectiveness.
The Project
New water treatment equipment is installed to reduce arsenic in a community's drinking water.
The water quality is then monitored to verify the effectiveness of the treatment. The equipment
used in Stewart installation is produced by ADEdge Technologies, Inc., working under a
Cooperative Research and Development Agreement. The equipment was matched to
characteristics of the source water. While Stewart will operate the new equipment, scientists
from Battelle, an EPA contractor in Ohio, will track the operation of the arsenic removal
technology by analyzing weekly water samples. EPA will use the results from this project and
others like it to demonstrate new methods for arsenic removal from drinking water.
more
Stewart's new arsenic water
treatment equipment
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The Goal
The goal of this project is to demonstrate and verify the effectiveness of ADEdge
Technologies, Inc., technology in reducing levels of arsenic in Stewart's drinking water from
around 42 parts per billion (ppb) to 10 ppb or lower. Operational cost is also being studied.
Expected Outcomes
•	Other small communities will gain knowledge about the performance of arsenic
removal technology through the results of the demonstration project. The results
will assist them in selecting the most appropriate and cost effective technology to
use at their sites.
•	Residents will benefit by having arsenic levels in their drinking water reduced
below 10 ppb, complying with the new EPA standard for arsenic in drinking
water.
Details about these demonstration projects can be found at this Web site:
http://www.epa.gov/ORD/NRMRL/arsenic.
Technical Contact: Tom Sorg - (513) 569-7370 - sorg.tom@epa.gov
June 27, 2006

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