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Government and People
Richard A. Rogers
Chief, Drinking Water Branch
U.S. EPA Region III
before the District of Columbia Council
Committee on Public Works and the Environment
March 17, 2004
Good afternoon. My name is Rick Rogers and I am the Chief of the Drinking Water Branch at the United States Environmental Protection Agency Mid-Atlantic Regional Office located in Philadelphia, Pennsylvania. The midAtlantic region is responsible for the oversight of the public water supply program of the District of Columbia.
Thank you for the opportunity to speak with you today regarding then steps that are being taken to reduce lead levels in the District of Columbia tap water.
The Technical Expert Working Group is taking many steps to reach a longterm solution to the corrosion of lead from water pipes and fixtures in the District. The Working Group will also attempt to determine the cause or causes of the elevated tap water lead levels.
The Technical Expert Working Group (TEWG) was formed to facilitate and expedite on-going research conducted by both WASA and the Washington Aqueduct (WA) of the Army Corps of Engineers as well as research already planned but not yet carried out. The U.S. Environmental Protection Agency Region III (EPA), WASA, WA and the D.C. Department of Health (DC DOH) recognized that an overarching planning and coordination effort was needed to help ensure that all the necessary research was conducted, to ensure no redundant efforts took place and to move the work along as quickly as possible.
The Group's mission is to develop a plan to reduce the corrosivity of treated drinking water in the District of Columbia to reduce consumers' lead exposure, through tap water. The mission of the TEWG is to determine, through bench-top, pilot scale and literature research, a revised optimal corrosion control treatment process for the Aqueduct. This re-optimized treatment will result in drastically reduced lead levels in the customer's tap water and WASA meeting EPA's lead action level
The Research Process and Reaching a Treatment Solution Decision
The research strategy is designed to reach a treatment decision that will reduce the corrosivity of the water through a three-part plan. The three parts are:
I want to make it clear that the regulatory process we must follow requires the Washington Aqueduct to develop a recommendation for a revised optimal corrosion control treatment that meets the approval of WASA and Falls Church and Arlington County, Vrrginia. It is EPA'a responsibility to review and approve the revised corrosion control treatment based on input from the experts of all parties involved. This will include feedback from an independent review panel selected by EPA's Office of Ground Water and Drinking Water in Washington, D.C. and from the District's Department of Health. EPA's and its contractor's involvement in the planning and implementation of this corrosion control treatment study is strictly limited to coordination and advisory roles. Being involved from the very beginning, however, will enable EPA to conduct a very rapid review and reach a decision on the proposed treatment very quickly.
The Technical Expert Working Group does not expect that any treatment selected and implemented will immediately reduce lead levels in the tap water. The Working Group expects lead levels to decrease over the course of implementing the revised treatment for at least several months. The Working Group also points out that, depending on the type of treatment selected, temporary changes in the aesthetic quality of the water may occur. These may be: a temporary release of rust from the water mains (red water) in some areas; an increase in calcium (lime) deposition in the water mains and in customers plumbing (if pH is adjusted higher with lime dosage); and an increase in indicator bacteria organisms, called total coliform bacteria.
The Washington Aqueduct and the Water and Sewer Authority will be taking every step possible to minimize the potential for these changes. One step will be performing an aggressive water main flushing program to help clear the lines prior to applying the revised corrosion control treatment. They will monitor the water very closely during the partial treatment application and during the application of the revised treatment across the entire system distribution system.
What Consumer Should Do Until Lead Levels Decrease
Since a treatment solution to the corrosivity will not likely see results until at least early 2005, consumers must continue to take action to lower their risk of lead exposure through tap water. The current corrosivity of the water can increase the leaching of lead from all lead-bearing plumbing products: from lead service lines to lead-bearing brass and bronze fixtures such as faucets. Therefore, there is a risk that tap water that has sat in household plumbing for more than several hours will have elevated lead concentrations, even in homes without lead service lines. Until the revised treatment scheme is in place and lead levels in tap water are reduced, the Technical Expert Working Group highly recommends that all consumers follow the tap flushing recommendations provided by EPA, WASA and the District of Columbia Department of Health (DCDOH) to reduce their exposure to lead in tap water. The Working Group also highly recommends that District residents follow the Department of Health's special advisory for children, nursing mothers and pregnant women who live in homes with lead service lines or in homes suspected of having lead service lines. These high-risk homes should also use the filtration devices that are to be distributed to them over the next month and follow the instructions that will be provided with the filters. I will repeat these recommendations to help further educate the public listening today:
Three Part Research Strategy
Three Teams within the Working Group are carrying out this Action Plan in a three-pronged approach. These are the Production Treatment Operations Team, the Distribution System Operations Team and the Communications Team.
Production Treatment Operations Team
The Production Treatment Operations Team is responsible for carrying out research and treatment deployment. This Team is lead by the Washington Aqueduct. This Team will conduct the detailed desktop analysis that will result in a treatment recommendation. This recommendation will be reached by researching the current water chemistry, treatment practices and distribution system components of the Washington Aqueduct wholesale customers and review corrosion inhibitor studies and corrosion treatment practices in similar treatment plants across the country. The treatment option expected to provide the greatest reduction in lead levels while minimizing adverse impacts will be selected.
This Team will also be conducting pipe loop studies to verify chemical dosages and help optimize the treatment once it is deployed system-wide. These pipe loops are being built at the Washington Aqueduct and will be run by the Aqueduct and their contractors.
The Production Treatment Operations Team will also lead the partial and full system application of the revised optimal corrosion control treatment. It is expected that the application of the revised treatment will occur around June 1, 2004 in a portion of the WASA distribution system called the 4th High Pressure Zone. This zone was selected because of three characteristics necessary for a partial system application. One characteristic is that this zone it is hydraulically isolated from the rest of the City's water distribution system. The second characteristic is that it has distribution system components that are representative of citywide conditions. The third characteristic is that a large pumping station that can house the equipment necessary to apply the revised treatment and deliver the treated water to the isolated section of the system serves this zone. The 4th High Pressure Zone is the Northern most corner of the District straddling both sides of Rock Creek Park.
After operating this partial system application for three months and if no major adverse impacts are seen, the Production Treatment Operations Team will begin the treatment application to the water delivered to the entire system. This is currently expected to occur around September 1, 2004.
Distribution System Operations Team
This Team `s responsibilities include performing baseline data gathering by collecting water samples in the distribution system, including in customers, homes. This Team is coordinated by DCWASA. Data gathered now will be used to measure the effectiveness of the selected corrosion control treatment. The Distribution System Operations Team is also conducting pipe loop studies to help determine the best treatment option and the correct dosages. Information from these pipe loop studies may also help determine the cause of the current corrosivity of the water. Lastly, this Team will be monitoring the effectiveness of the selected treatment option in both the partial system application and the full system deployment of the revised optimal corrosion control treatment.
The Communications Team will be lead jointly by EPA Region III and the District of Columbia Department of Health. They will carry out their responsibilities with input from the entire working group, agency public affairs specialists, community involvement staff, and any private contractor who may be hired to provide specialized communication of technical information, particularly health issues, to the general public on a large scale. Public involvement in the development and implementation of this communications plan will be encouraged and will play a key role in the plan's success.
This Team will be responsible for: highlighting short-term risk reduction activities consumers should take until a revised treatment scheme is working; coordinating messages with the public health agencies to communicate health effects from lead in drinking water should consensus risk values be developed; communicating research progress and activities of most interest to the public on a regular basis; and continue to describe the goals the Lead and Copper Rule so that the public can learn to accurately differentiate the lead action level from health based standards.
Progress To Date
The Distribution Systems Operations Team is completing the assembly of seven mini pipe loops at their Ft. Reno Pumping Station facility. These are pipe loops that were designed and assembled in Seattle, Washington over the past three weeks by corrosion experts at HDR, Inc. and the University of Washington. Several pipe loops are already operating with water flowing through them. Preliminary results should start being compiled in two to three weeks. Another quick study to be completed by this team will measure the rate at which lead leaches into the water from lead service lines.
The Distribution System Team is also gathering additional data on the behavior of lead service lines and the levels of lead found in them by conducting additional profile sampling in customers' homes. They are also gathering the baseline data on current chemical conditions in the distribution system. This Team is developing extensive monitoring plans to further develop the baseline data against which post-treatment data will be compared for assessing success of the treatment. This will also be done in conjunction with the Virginia utilities.
WASA's contractors are pulling lead service line pipe from the ground to be used in the pipe loop and elemental analytical studies. WASA is also ramping up to implement a water main flushing program to help prepare the distribution to for the revised treatment process. Citizens will see the water main flushing program implemented first in the section of the City where the partial system application is deployed. Later this spring and throughout the summer, the water main flushing program will extend throughout the entire City
EPA's corrosion expert in the Office of Research and Development in Cincinnati, Ohio has completed sophisticated analyses of the chemical make-up of the mineral buildup, or scale, on the inside of a sample of lead service line pipe. The analyses included specialized laboratory methods such as X-ray defraction at EPA's laboratories and Xanes spectroscopy work done at Argonne National Laboratories, Argonne Illinois. Full elemental analysis will be completed at a U.S. Geological Survey laboratory in Denver, Colorado.
The Production Systems Operations Team is completing the desktop analysis that will point to the best treatment option. This literature research and computer modeling is currently being conducted. The desktop analysis is expected to be complete by April 1, 2004.
This Team is also constructing a larger, flow-through pipe loop at the Washington Aqueduct's Dalecarlia Water Treatment Plant. This pipe loop will be used to verify results from the mini-pipe loop studies and will help define the appropriate dosage of whatever treatment chemical is decided upon. They are also planning for the partial and full system deployment of the selected treatment chemical by completing engineering designs for the likely treatment options being considered. This is being done now, so that no time is lost in purchasing and installing the necessary equipment to apply the revised treatment scheme.
EPA's Office of Ground Water and Drinking Water in Washington, D.C. is assembling an independent peer review panel to review this action plan, research results and the recommended treatment option selected. The panel will be made up of a representative from a large private utility, a state agency water treatment expert and two independent corrosion control experts.
The target schedule for all activities being undertaken by the working group is:
At this time, we would be happy to answer any of your questions.
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