DETECTION PROBABILITIES AND SYSTEM ...

DETECTION PROBABILITIES AND SYSTEM ANALYSIS OF THE MISSISSIPPI RIVER EARLY WARNING ORGANIC COMPOUND DETECTION SYSTEM

Michael G. Waldon~ Kenneth K. O'Hara~ Jr., and Duane E. Everett,

Respectively: Research Associate Pro~essor, Center ~or Louisiana Inland Water Studies, University o~ Southwestern Louisiana, P.O. Box 42291, La~ayette, LA 70504; Environmental Quality Specialist, Louisiana Department o~ Environmental Quality, P.O. Box 82215, Baton Rouge, LA 70884; and Research Associate~ and Research Associate, Center ~or Louisiana Inland Water Studies, University o~ Southwestern Louisiana, P.O. Box 42291, Lafayette, LA 70504;

11 April 1991

ABSTRACT: This report presents a probabilistic analysis o~ the Mississippi River Early Warning Organic Compound Detection System . EWOCDS is a monitoring network which is intended to provide early warning of excessive organic pollutant levels to water treatment plants with intakes on the River. In this study the probability o~ detection o~ an instantaneous spill as it passes one or more monitoring stations is considered. It is concluded that these probabilities are highly dependent on River discharge.Further, it is concluded that a sampling ~requency o~ once per day is generally inadequate to proVIde reliable warning.Improved sample scheduling and sampling procedures are also discussed. INTRODUCTION This report presents the results o~ a study o~ the design of the Mississippi River Early Warning Organic Compounds Detection System . In an e~~ort to improve the early warning response for these water providers,the Early Warning Organic Compound Detection System was established in 1986. The system design was based on an early warning and water monitoring system which had been implemented by the Ohio River Valley Water

Sanitation Commission

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TABLE 3.

Single station detection probabilities.

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