The Department of Environmental Protection is seeking proposals from consulting engineers interested in performing tracer studies at approximately 106 surface water treatment plants.

The 86 targeted facilities serve at least 10,000 persons but fewer than 50,000 people. In addition, 20 tracer studies will occur at smaller plants that have changed disinfection design and practice as a result of previous tracer studies. About 35 systems would undergo a tracer study each year in Pennsylvania.

The studies will prepare drinking water suppliers for the “balancing act” of maintaining adequate Giardia and virus inactivation at all times while avoiding over-disinfection that can lead to disinfection byproduct formation. Currently, surface water suppliers may be unaware of the actual short-circuiting that is occurring in chlorine contact basins.

The tracer studies will not only improve public heath protection in the Commonwealth, but they will also enable suppliers to comply with increasingly more stringent and complex regulations.

For more information contact David Hissner at 717-772-4018 ore-mail dahissner@state.pa.us .

4/15/2005