James A. Goodrich

Real-time contaminant detection and classification in a drinking water pipe using conventional water quality sensors: techniques and experimental results.

Accurate detection and identification of natural or intentional contamination events in a drinking water pipe is critical to drinking water supply security and health risk management. To use conventional water quality sensors for the purpose, we have explored a real-time event adaptive detection, identification and warning (READiw) methodology and examined it using pilot-scale pipe flow experiments of 11 chemical and biological contaminants each at three concentration levels. The tested contaminants include pesticide and herbicides (aldicarb, glyphosate and dicamba), alkaloids (nicotine and colchicine), E. coli in terrific broth, biological growth media (nutrient broth, terrific broth, tryptic soy broth), and inorganic chemical compounds (mercuric chloride and potassium ferricyanide). First, through adaptive transformation of the sensor outputs, contaminant signals were enhanced and background noise was reduced in time-series plots leading to detection and identification of all simulated contamination events. The improved sensor detection threshold was 0.1% of the background for pH and oxidation-reduction potential (ORP), 0.9% for free chlorine, 1.6% for total chlorine, and 0.9% for chloride. Second, the relative changes calculated from adaptively transformed residual chlorine measurements were quantitatively related to contaminant-chlorine reactivity in drinking water. We have shown that based on these kinetic and chemical differences, the tested contaminants were distinguishable in forensic discrimination diagrams made of adaptively transformed sensor measurements.

Assessing the water quality impacts of future land-use changes in an urbanising watershed

An integrated watershed hydrologic model, the Soil and Water Assessment Tool (SWAT) was adopted in this study to simulate the water quality conditions under the current and the future land-use configurations. The findings were compared to determine the hydrologic consequences of future land-use changes. Results indicate that as the land use in the watershed shifts from predominantly agricultural to mixed rural and residential lands, a reduction in flow, sediments, and nutrients is detected. Although the projected average daily concentration of phosphorus is reduced by 47% under the future land-use scenario, it will still exceed the daily limit suggested by the US Environmental Protection Agency. From this study, it is evident that SWAT is a reliable water quality model, capable of producing accurate information for environmental decision-making. The model has a GIS interface and is coupled with the Better Assessment Science Integrating Point and Nonpoint Sources system. It is, therefore, a valuable tool for environmental informatics.

Drinking water and cancer mortality

The problem of understanding the possible adverse health effects of organic chemical contaminants in drinking water is not new, but national concern has intensified in recent years. Despite this concern and regulatory efforts, no definitive relationship has been established between organic contamination and human health effects. This paper examines some of the sources of possible organic contamination, current knowledge concerning human health effects and the most current epidemiological data. Historic CCE and CAE data were extracted from STORET and used in regression analyses. Age-adjusted 20-year average cancer mortality rates were regressed against the sum of CAE and CCE for those counties with STORET monitoring data of their drinking water source. Results indicate statistically highly significant relationships particularly for GI-urinary tract cancers.

Detention Outlet Retrofit Improves the Functionality of Existing Detention Basins by Reducing Erosive Flows in Receiving Channels

By discharging excess stormwater at rates that more frequently exceed the critical flow for stream erosion, conventional detention basins often contribute to increased channel instability in urban and suburban systems that can be detrimental to aquatic habitat and water quality, as well as adjacent property and infrastructure. However, these ubiquitous assets, valued at approximately

An Overview of U.S. EPA Research on Remote Monitoring and Control Technologies for Small Drinking Water Treatment Systems

600,000 per km2 in a representative suburban watershed, are ideal candidates to aid in reversing such cycles of channel degradation because improving their functionality would not necessarily require property acquisition or heavy construction. The objective of this research was to develop a simple, cost-effective device that could be installed in detention basin outlets to reduce the erosive power of the relatively frequent storm events (~ < two-year recurrence) and provide a passive bypass to maintain flood control performance during infrequent storms (such as the 100-year recurrence). Results from a pilot installation show that the Detain H2O device reduced the cumulative sediment transport capacity of the preretrofit condition by greater than 40%, and contributed to reduced flashiness and prolonged baseflows in receiving streams. When scaling the strategy across a watershed, these results suggest that potential gains in water quality and stream channel stability could be achieved at costs that are orders of magnitude less than comparable benefits from newly constructed stormwater control measures.

Drinking Water Supply Management: An Interactive Approach

There are approximately 160,000 small community and non-community drinking water treatment systems in the United States. According to recent estimates, small systems contribute to 94% of the Safe Drinking Water Act violations annually. A majority of these are for microbiological MCL violations. Small drinking water system research is being conducted at the U.S. EPA’s Test & Evaluation (T&E) Facility in Cincinnati, Ohio with an emphasis on “package plants” for biological, physical, and chemical treatment of drinking water sources. Research studies are designed to provide guidance to operators of small Public Water Systems to ensure compliance with current regulations including the Surface Water Treatment Rule and the Groundwater Rule. Several U.S. EPA studies have focused on packaged filtration and disinfection systems equipped with remote telemetry units and Supervisory Control and Data Acquisition (SCADA) systems. SCADA systems are commonly used by large (not small) water utilities to control and monitor their operations. However, the constant monitoring requirements for small system operators in remote locations can incur substantial costs in time and travel. Remote monitoring and control systems offer a cost-effective way to reduce manpower requirements by providing real-time monitoring of water quality, continuous control of operating conditions, and the reporting of information electronically from a “centralized” location. Disclaimer This paper has been reviewed in accordance with the EPAs peer and administrative review policies and approved for presentation and publication. The mention of trade

Understanding the Impact of Mesh on Tank Overflow System Capacity

In February 1977, a massive discharge of carbon tetrachloride into the Kanawha River in West Virginia threatened much of the Ohio Valley with contaminated drinking water potentially affecting over one million consumers. This episode heightened the awareness of consumers and decision-makers alike to the relationship between wastewater discharges and drinking water consumption. This article examined the results of a study motivated by the carbon tetrachloride spill and examined interactions between industrial discharges and drinking water consumption in surface water supplies. The mechanism used to study the wastewater discharge water supply intake interaction was a water quality/quantity simulation model QUAL-II. QUAL-II was used to provide a framework to bring the diverse elements of mathematic modeling, fluid dynamics, organic chemistry and geography to create an interactive systems analysis approach that can have an impact on public policy in drinking water. INTRODUCTION In February 1977, a massive discharge of carbon tetrachloride into the Kanawha River in West Virginia threatened much of the Ohio River Valley with contaminated drinking water potentially affecting over one million consumers. This episode heightened the awareness of consumers and decision-makers alike to the relationship between wastewater discharges and drinking water consumption.

Evaluation and application of the optical image profiler (OIP) a direct push probe for photo-logging UV-induced fluorescence of petroleum hydrocarbons

A 2016 incident that resulted in damage to a water storage tanks roof motivated pilot-scale experiments to be conducted to determine the impact of mesh on tank overflow capacity. A clean mesh installed near the outlet of an overflow system did not reduce the capacity during the weir dominated flow regime. The impact of a mesh was found to be a reduction in the area available to flow, which was found to lower the achievable capacity through the system. Considering only the head loss or pressure drop associated with the mesh and not area reduction resulted in an overestimation of achievable capacity, which could lead to an undersized overflow system. The results and formulas presented will help water utilities ensure overflow systems with mesh are appropriately sized.

MULTIPLE SATELLITES REMOTE SENSING IMAGES FOR THE DERIVATION OF A WATER AVAILABILITY INDEX

The presence of free phase petroleum fuels in the subsurface (often called light nonaqueous phase liquids/LNAPL) is a hazard in almost every town and city in the modern world. Leaking underground storage tanks and the resulting contamination and hazards have proven to be a challenge to investigate and remediate. One issue is adequately characterizing the presence and spatial extent of LNAPLs in the subsurface. Experience has shown that conventional soil coring methods and groundwater monitoring methods are fraught with limitations that can lead to significant errors in the estimation of the amount and spatial distribution of LNAPLs in the subsurface. This leads to the development of inaccurate conceptual site models and costly errors in remedial actions. A new direct push logging tool, the optical image profiler (OIP), has been developed to obtain high resolution site characterization data to more accurately define the presence and extent of LNAPLs in unconsolidated materials. The OIP system uses a downhole ultraviolet light-emitting diode to induce fluorescence of fuel LNAPL. A small complimentary metal–oxide–semiconductor camera mounted inside the probe behind a sapphire window captures photographic images of visible range fluorescence as the probe is advanced by direct push methods. In situ images of subsurface fuel fluorescence have not previously been available to the investigator and may further the understanding of LNAPL behavior. The OIP software also provides a log of percent area fluorescence (%AF) based on analysis of the images. An electrical conductivity (EC) dipole on the probe provides a log of bulk formation EC that is often a good indicator of formation lithology. The information presented here explains the basic design and operation of the OIP system in the field. Bench tests confirm the capability of the OIP system to detect a range of petroleum fuels. Field studies with the tandem EC and %AF logs are used to identify LNAPL and its migration pathways in the subsurface. These capabilities can improve the management and remediation of LNAPL-impacted sites and reduce long-term costs associated with cleanup and closure.

AST/R-Based Water Reuse as a Part of the Total Water Solution for Water-Stressed Regions: An Overview of Engineering Practice and Regulatory Prospective

Recent drought events in the U.S. have threatened drinking water supplies for communities in Maryland and Chesapeake Bay in 2001 through September 2002, Lake Mead in Las Vegas in 2000 through 2004, the Peace River and Lake Okeechobee in South Florida in 2006, and Lake Lanier in Atlanta, Georgia in 2007. In the environmental science community, there is a renewed interest to develop a new “Water Availability Index (WAI)” that serves for shortterm water resources planning and water infrastructure management in dry periods. Such a development may be geared toward presenting a near real-time, risk informed and forwardlooking instrumental message in terms of both the quantity and quality of available fresh water in major metropolitan regions. The success of this effort could incorporate the use of integrated remote sensing technologies in concert with intermediate- and long-term climate change forecasts. It is the aim of this paper to present a state-of-the-art review about: 1) How the multi-scale and multi-dimensional databases are collected by optical and microwave satellite images, such as the NASA GOES, MODIS Terra and Aqua etc., and ground-based radar stations, such as the NOAA NEXRAD system, and 2) How these databases can be applied to support the development of a new WAI and help reduce the managerial risks of water infrastructure across the continental U.S. These discussions lead to the derivation of a new WAI with the aid of remote sensing technology.