With the passage of the Bioterrorism Preparedness and Response Act in 2002, all community water systems serving populations greater than 3,300 people were required to conduct vulnerability assessments, certify completion, and provide a written report to the U.S. EPA. The Bioterrorism Act requires that all emergency response plans, at a minimum, include plans, procedures and identification of equipment that could be used in the event of an intentional attack on a water treatment system. In addition, assessments must include actions, procedures and identification of equipment that could lessen the impact of such an attack.
In September 2003, the state of Delaware—in an effort to help state water utilities comply with the new federal regulations—applied for a grant from the Department of Homeland Security to purchase a Severn Trent Eclox™ Rapid Response Water Test Kit for use by the DRWA. Compact and weighing less than 20 lb, the kit uses chemiluminescence to measure the amount of light generated when a water sample is combined with reagents. This enhanced chemiluminescence reaction produces light in direct proportion to the quality of the sample and is used to determine the relative toxicity of the water.
The chemiluminescence reaction utilizes the plant enzyme horseradish peroxidase to catalyze the oxidation of luminol, producing a flash of light. An enhancer is added to the sample to stabilize and prolong the emission of light produced by the reaction. The presence of free radical scavengers interferes with the reaction, and toxicants in a sample interact with the enzyme to reduce light emissions.
The chemiluminescence test is broadband and qualitative, and is used to quickly ascertain whether the sample measured has been subjected to chemical or biological contamination. Eclox has specific tests to measure for arsenic, pesticides, nerve agents, pH, total dissolved solids, and color and chlorine content, and it is sensitive to heavy metals, poisons and chemical warfare agents.
Prior to testing the water sample, a baseline reading is established using deionized water and relative instrumentation included in the kit. The deionized water is exposed to the reagents and the light generated is stored as a reference level. The test is then repeated with the water sample.
Depending on the level of toxins in the sample, light levels are reduced relative to the reference sample. The ratio of the light levels in the sample water and the deionized water provides an indication of the toxicity level of the sample.
Test information is immediately viewable on the luminometer display, with completed test results available in four minutes. The luminometer rapidly indicates the quality of the tested sample and is used to indicate whether more extensive tests are required to identify the nature of the contaminants. If the luminometer results indicate that the sample is high in quality, typically, no further testing is required.
Once a year, DRWA circuit riders—professionals who provide technical assistance and other services to association members—use the Eclox kit to test the water in each of the state's municipal water systems according to EPA guidelines. They test distribution systems and wells in alternating years.
Perhaps of even greater value to the DRWA and its membership—and the peace of mind of customers of the 27 municipally owned water utilities—is the association's ability to respond to emergencies and contamination threats. There was one such occurrence earlier this year.
On the morning of Jan. 16, 2006, while on routine distribution checks in the town of Selbyville, a water operator noticed the safety cage ladder door to one elevated water storage tank was open. The operator also observed that a door to a nearby building where pipe fittings and miscellaneous supplies were stored was open. Fearing a possible case of vandalism or worse, the operator immediately called the local and state police. The operator also called the DRWA. Within 30 minutes, a DRWA representative arrived at the storage tank site, was briefed on the situation, and immediately put into effect the emergency response plan. The storage tower was isolated and Selbyville's other water storage tank began to handle all water distribution services for the town.
Within two hours of the operator's first report, a DRWA staff member had used the Eclox kit to sample the tank’s water for contamination. All tests were negative. It was a false alarm. (It was later determined that a tank inspection company had left the safety cage ladder door open.)
According to Rick Duncan, DRWA executive director, “We're accountable to the residents of Delaware to provide a safe water supply. With the Eclox kit, we have a tool we can use in potential emergencies such as the false alarm we experienced earlier this year, but also for the ongoing water monitoring and analysis needs of our member water companies.”
Duncan also noted that the organization has earned a national reputation as a trendsetter. “We're getting calls from chemists and water system managers across the country asking about Eclox,” Duncan said.
In an environment of continued uncertainty, communities must remain diligent in their safety procedures and emergency response plans. Using the newest available technology, routinely testing water for contamination can be fast, easy and inexpensive.