Full Description

The safety and security of major infrastructure systems in the United States, including drinkingwater distribution systems, has recently come under reassessment. Several chemical andbiological agents have been identified that could constitute a credible threat against a waterdistribution system. In order to protect drinking water supplies, the U.S. EnvironmentalProtection Agency (USEPA) initiated a program in 2003 to investigate real time sensors that may beused to trigger a contamination event and support early warning systems (EWS) within a waterdistribution system. These sensors monitor for standard drinking water parameters such as pH,free chlorine, oxygen reduction potential, dissolved oxygen, specific conductance, turbidity, totalorganic carbon, chloride, ammonia, and nitrate. The research was conducted on a recirculatingpipe loop at the USEPA's Test and Evaluation Facility in Cincinnati, Ohio. The experimental resultsindicate that the parameters of free and total chlorine, total organic carbon (TOC), OxygenReduction Potential (ORP), specific conductance and chloride were consistently able to indicatea change in water quality due to injections of various contaminants into the pipe loop. Researchis also being conducted to determine the minimum contaminant dose required to trigger a sensoralarm. Contaminants tested to date include secondary effluent from a waste water treatmentplant, potassium ferricyanide, arsenic trioxide, nicotine, aldicarb, E. coli K-12 strain with growthmedia, insecticide containing malathion, and a herbicide containing glyphosate. Future testingwith chemical and biological warfare agents has been initiated. Includes 5 references, tables, figures.

Product Details

Edition: Vol. - No. Published: 04/10/2005 Number of Pages: 16 File Size: 1 file , 430 KB