Witness Testimony

Good Morning, Chairman Gillmor and members of the Committee. I am Tom Jacobus, the General Manager of Washington Aqueduct.

We appreciate the opportunity to be here today to report to this committee the actions Washington Aqueduct is taking and the progress we are making to reduce the elevated concentrations of lead in the drinking water found in some homes in the District of Columbia.

Corrosion control has always been an integral part of the water treatment process. After the Lead and Copper Rule was promulgated in 1991, Washington Aqueduct, based on the recommendations of its consultant and in coordination with its wholesale customers, i.e., the District of Columbia, Arlington County, Virginia and the City of Falls Church, Virginia, conducted studies to determine the optimal corrosion control treatment that would meet the requirements of the rule.

Corrosion control based on maintaining a target pH of the finished water through the use of granulated lime was the recommended technique, and after a series of reviews and discussions, Region 3 of the United States Environmental Protection Agency approved that strategy. Washington Aqueduct has paid very close attention to meeting the chemistry required by the optimal corrosion control treatment designation, and results from samples drawn from the customers' water validated the effectiveness of the process for many years.

However, in 2002 the District of Columbia Water and Sewer Authority's sampling under the provisions of the Lead and Copper Rule produced results that exceeded the action level for lead. That triggered the replacement of a percentage of their lead service lines. These results also led the Environmental Protection Agency to begin a review of the situation. Washington Aqueduct participated in this review by supplying water quality data to the Environmental Protection Agency's contractor conducting this investigation.

In November 2000, Washington Aqueduct added chloramines as a secondary disinfectant to come into compliance with the newly promulgated Stage I, Disinfectants, Disinfection Byproducts Rule. In making that conversion, Washington Aqueduct and its consultants did extensive research into potential side effects of using chloramines. As a result, we took steps to watch for nitrification in the distribution system that could reduce the pH of the water and consequently increase the corrosiveness of the water. We saw no evidence that the new chloramine disinfection process was increasing the corrosiveness of the water via the nitrification process. The chemistry change did, as expected, result in significantly lower levels of disinfection byproducts.

However, the lead concentrations found among a large number of samples collected by the District of Columbia Water and Sewer Authority in 2002 and 2003 did indicate that Washington Aqueduct's optimal corrosion control treatment that had previously been working successfully to prevent leaching of lead from service lines was no longer giving adequate protection.

Since February 2, 2004, our highest priority has been to reevaluate the corrosion control treatment we use to protect the end users of the drinking water in the District of Columbia and Northern Virginia from the naturally corrosive effects of the water and to develop a treatment modification to make the water less corrosive.

A Technical Expert Working Group consisting of Washington Aqueduct and its consultants, the Environmental Protection Agency, the District of Columbia Water and Sewer Authority and its consultants, the District of Columbia Department of Health, Arlington County, Virginia and the City of Falls Church, Virginia, was established to assist Washington Aqueduct develop a new corrosion control treatment strategy. Incorporating advice from the Environmental Protection Agency's independent peer review panel, we have selected a new corrosion inhibitor chemistry based on an orthophosphate compound and have begun to install equipment that will be used to modify the corrosion control treatment in a way that we believe will reduce the concentrations of lead in drinking water that remains in contact with lead pipes, lead solder joints and fixtures. This will go into place even as lead service lines are being replaced.

In arriving at this treatment change, we have had access to the nation's very best scientific and technical talent in this field. We appreciate the resources that the Environmental Protection Agency has expended to assist not only us but also to look at the larger aspects of this issue.

In the process of doing this, we have worked closely with our wholesale customers in the District of Columbia and Virginia, our colleagues in the departments of health in the District of Columbia and Virginia, and the United States Environmental Protection Agency. We have also participated in many meetings throughout the District of Columbia to explain to the residents the nature of the problem and our approach to a solution.

A partial system application of the phosphate-based corrosion inhibitor in a portion of the District of Columbia Water and Sewer Authority distribution system began on June 1, 2004. In mid-August we will begin a full system application that will include not only the District of Columbia but the Arlington County and the City of Falls Church distribution systems in Virginia as well. We are approaching the application in two steps to be able to carefully control and evaluate the initial application to ensure that the programmed dose of the inhibitor does not generate any unexpected secondary effects. One known possible effect of the application of the corrosion inhibitor may be the localized release of rust from iron pipes. This would result in discolored water delivered to the consumer, but it will be short-term phenomena and can be managed by flushing the distribution system mains as needed. So far in the partial system application no discolored water has been observed at the customers' taps.

As part of our conversion to a corrosion inhibitor, we will be installing a series of lead pipe loops made of pipe removed from service in the District of Columbia Water and Sewer Authority distribution system. They will simulate conditions in the lead service lines still in the distribution system under a variety of scenarios. These loops will be the basis of scientific studies over the next year to evaluate the effectiveness of the treatment change as well as to optimize chemical dosage and types. All of this information will be shared with the water utility industry, the scientific community, and the public to add to the knowledge base on corrosion and corrosion chemistry.

This concludes my testimony. I will be happy to respond to any questions.