Groundwater Protection Program Research Articles

Groundwater Management Protection Program for Nigeria

This article looks into groundwater pollution in Nigeria; groundwater uses and suggests how to go about protection of Nigeria’s underground water. There were case studies of wells at different regions; content analysis indicated physical, chemical and organic factors with parameters that surpassed upper boundaries established by World Health Organization. The public full understanding of economic and social importance of underground water will help in Full integration of Comprehensive Regional Groundwater Protection Program for Nigeria.

Assessing groundwater vulnerability in the Kinshasa region, DR Congo, using a calibrated DRASTIC model

This study assessed the vulnerability of groundwater against pollution in the Kinshasa region, DR Congo, as a support of a groundwater protection program. The parametric vulnerability model (DRASTIC) was modified and calibrated to predict the intrinsic vulnerability as well as the groundwater pollution risk. The method uses groundwater body specific parameters for the calibration of the factor ratings and weightings of the original DRASTIC model. These groundwater specific parameters are inferred from the statistical relation between the original DRASTIC model and observed nitrate pollution for a specific period. In addition, site-specific land use parameters are integrated into the method. The method is fully embedded in a Geographic Information System (GIS). Following these modifications, the correlation coefficient between groundwater pollution risk and observed nitrate concentrations for the 2013–2014 survey improved from r = 0.42, for the original DRASTIC model, to r = 0.61 for the calibrated model. As a way to validate this pollution risk map, observed nitrate concentrations from another survey (2008) are compared to pollution risk indices showing a good degree of coincidence with r = 0.51. The study shows that a calibration of a vulnerability model is recommended when vulnerability maps are used for groundwater resource management and land use planning at the regional scale and that it is adapted to a specific area.

A Comparative Assessment Between Three Machine Learning Models and Their Performance Comparison by Bivariate and Multivariate Statistical Methods in Groundwater Potential Mapping

As demand for fresh groundwater in the worldwide is increasing, delineation of groundwater spring potential zones become an increasingly important tool for implementing a successful groundwater determination, protection, and management programs. Therefore, the objective of current study is to evaluate the capability of three machine learning models such as boosted regression tree (BRT), classification and regression tree (CART), and random forest (RF), and comparison of their performance by bivariate (evidential belief function (EBF)), and multivariate (general linear model (GLM)) statistical methods in the groundwater potential mapping. This study was carried out in the Beheshtabad Watershed, Chaharmahal-e-Bakhtiari Province, Iran. In total, 1425 spring locations were detected in the study area. Seventy percent of the spring locations were used for model training, and 30 % for validation purposes. Fourteen conditioning-factors were considered in this investigation, including slope angle, slope aspect, altitude, plan curvature, profile curvature, slope length (LS), stream power index (SPI), topographic wetness index (TWI), distance from rivers, distance from faults, river density, fault density, lithology, and land use. Using the above conditioning factors and different algorithms, groundwater potential maps were generated, and the results were plotted in ArcGIS 9.3. According to the results of success rate curves (SRC), values of area under the curve (AUC) for the five models vary from 0.692 to 0.975. In contrast, the AUC for prediction rate curves (PRC) ranges from 77.26 to 86.39 %. The CART, BRT, and RF machine learning techniques showed very good performance in groundwater potential mapping with the AUC values of 86.39, 86.12, and 86.05 %, respectively. By the way, The GLM and EBF models in comparison by machine learning models showed weaker performance in spring groundwater potential mapping by the AUC values of 77.26, and 67.72 %, respectively. The proposed methods provided rapid, accurate, and cost effective results. Furthermore, the analysis may be transferable to other watersheds with similar topographic and hydro-geological characteristics.

Numerical simulation of tritium migration in groundwater at Wolsong Plant 1 site

On-site groundwater has been reported to be contaminated by the unplanned release of liquid radioactive material at some nuclear power plants. Thus, it is of utmost importance to implement a timely and effective groundwater protection program at a site based on a good understanding of groundwater flow and a reasonable prediction for the potential impact of the unplanned release. In this study, the tritium migration has been simulated based on the modeling result of groundwater at Wolsong Plant 1 site to assess the potential impact of an unplanned release in the form of a leak. The results indicate that the groundwater eventually flowed into the sea, leaving marine activities as the only possible exposure pathway for receptors. Furthermore, the tritium concentrations in groundwater were simulated to be lowered very quickly with groundwater approaching the sea. Therefore, an additional radiation dose contribution due to the discharge of the contaminated groundwater was estimated to be negligible. Particularly, the draining effect of the dewatering sumps was shown to have a strong influence on the groundwater flow characteristics and the simulation of tritium migration, mainly decreasing the spread rate of the contaminated groundwater, which is advantageous to the protection of groundwater.

Positive and negative impacts of five Austrian gravel pit lakes on groundwater quality

Groundwater-fed gravel pit lakes (GPLs) affect the biological, organic, and inorganic parameters of inflowing groundwater through combined effects of bank filtration at the inflow, reactions within the lake, and bank filtration at the outflow. GPLs result from wet dredging for sand and gravel and may conflict with groundwater protection programs by removing the protective soil cover and exposing groundwater to the atmosphere.We have investigated the impact on groundwater of five GPLs with different sizes, ages, and mean residence times, and all having low post-excavation anthropogenic usage. The results revealed highly active biological systems within the lake water, in which primary producers significantly reduced inflowing nitrate concentrations. Decalcification also occurred in lake water, reducing water hardness, which could be beneficial for waterworks in hard groundwater areas. Downgradient groundwater nitrate and calcium concentrations were found to be stable, with only minor seasonal variations. Biological degradation of organic material and organic micropollutants was also observed in the GPLs. For young GPLs adequate sediment deposits may not yet have formed and degradation processes at the outflow may consequently not yet be well established. However, our results showed that within 5years from the cessation of excavation a protective sediment layer is established that is sufficient to prevent the export of dissolved organic carbon to downgradient groundwater.GPLs can improve groundwater quality in anthropogenically (e.g., pesticides and nitrate) or geologically (e.g., hardness) challenging situations. However, post-excavation usage of GPLs is often dominated by human activities such as recreational activities, water sports, or fish farming. These activities will affect lake and groundwater quality and the risks involved are difficult to predict and monitor and can lead to overall negative impacts on groundwater quality.

What Can We Learn From Exemplary Groundwater Protection Programs?

Source water protection is receiving considerable attention due to contamination concerns related to drinking water. While this important issue has intensified over the past decade, several municipalities in Canada and the United Stated have considerable experience with practicing groundwater protection. This research investigates wellhead protection programs in the Region of Waterloo (Ontario) and the City of Dayton (Ohio). The context and process of developing these exemplary municipal groundwater protection programs are described. Cross-case analysis compares the cases in terms of the development process, employment of regulatory and non-regulatory tools, points of innovation, and challenges confronted. Experiences from these cases confirms the need for an appropriate mix of tools for groundwater protection, the importance of organizational capacity and the need for supportive and flexible institutional arrangements. Suggestions are offered for municipalities undertaking groundwater protection programs.

Conjoint Analysis of Groundwater Protection Programs

Three conjoint models—a traditional ratings model, a ratings difference specification, and a binary response model—were used to value groundwater protection program alternatives. The last, which is virtually identical to a dichotomous choice contingent valuation specification, produced the smallest value estimates. This suggests that the conjoint model is very sensitive to model specification and that traditional conjoint models may overestimate economic value because many respondents are not in the market for the commodity being valued.

Conceptual Design of a System for Selecting Appropriate Groundwater Models in Groundwater Protection Programs

/ An effective groundwater protection program requires understanding of water flow and contaminant transport processes in the subsurface. Although many mathematical models have been developed to simulate the processes, few actually are used in groundwater protection programs due to the difficulties in data collection, model selection, and model implementation. This study presents a conceptual design of a GIS-supported model selection system that evaluates available data and mathematical models to facilitate groundwater protection programs. Steady-state groundwater and contaminant transport models applied in isotropic aquifers are placed into four classes to simulate conservative or nonconservative contaminant transports in simple or complex geohydrological conditions. After analyzing specific study objectives, available data, and model requirements, the proposed system selects a class of models that can be used in simulation and recommends any need for additional data collection. This study initiates an effort to integrate GIS, mathematical models, and expert knowledge in one system to promote the application of appropriate groundwater models. The new technology of GIS and digital data-base management makes it possible to develop such a system in practice.KEY WORDS: Groundwater models; Geographic information systems

Illinois Community Examines Aquifer Protection Measures

Marengo, a community in northern Illinois with a population of 4,768, is developing a comprehensive management program to protect the city's groundwater resources. The city has established a groundwater protection team to evaluate various site‐specific programs for managing and protecting the community's five‐year recharge area. This paper discusses the various aspects of Marengo's groundwater protection program including a voluntary pollution prevention program for area businesses.

Well Water Quality, Well Vulnerability, and Agricultural Contamination in the Midwestern United States

The Heidelberg College Cooperative Private Well Testing Program is designed to evaluate water quality in private rural wells. The program inexpensively provides large datasets that reflect relationships between well contamination and associated factors, and support local groundwater protection and education programs. Nearly 35 000 wells have been tested in Ohio, Indiana, Illinois, West Virginia, and Kentucky. Median nitrate concentration was 0.07 mg/L ; 3.4% of wells exceeded the drinking water standard of 10 mg/L ; 23% exceeded 1 mg/L. Triazines were detected in 4.9% of 12 362 samples ; the atrazine MCL of 3.0 μg/L was exceeded in 0.1% of samples. Acetanilides were detected in 9.7% of 10 967 samples ; 1.1% exceeded the alachlor MCL of 2.0 μg/L. Many acetanilide detections, and most higher concentrations, are due to an alachlor breakdown product and involve little or no alachlor. Information supplied by well owners was used to examine the impact of cultural and geological factors on well water quality. Concentrations are higher in wells that are shallower, older, dug, or driven ; located close to cropland, feedlots, or chemical mixing sites ; or located in sandy soils. Where wells combine the most vulnerable alternative for two or three factors, the probability of contamination increases dramatically. Mapping sometimes reveals spatial patterns of contamination that reflect geological influences. River valley aquifers, sandy soils with high water tables, karst areas, and reef structures with surficial expressions are all reflected in county maps of the data.

Well Water Quality, Well Vulnerability, and Agricultural Contamination in the Midwestern United States

AbstractThe Heidelberg College Cooperative Private Well Testing Program is designed to evaluate water quality in private rural wells. The program inexpensively provides large datasets that reflect relationships between well contamination and associated factors, and support local groundwater protection and education programs. Nearly 35 000 wells have been tested in Ohio, Indiana, Illinois, West Virginia, and Kentucky. Median nitrate concentration was 0.07 mg/L; 3.4% of wells exceeded the drinking water standard of 10 mg/L; 23% exceeded 1 mg/L. Triazines were detected in 4.9% of 12 362 samples; the atrazine MCL of 3.0 µg/L was exceeded in 0.1% of samples. Acetanilides were detected in 9.7% of 10 967 samples; 1.1% exceeded the alachlor MCL of 2.0 µg/L. Many acetanilide detections, and most higher concentrations, are due to an alachlor breakdown product and involve little or no alachlor. Information supplied by well owners was used to examine the impact of cultural and geological factors on well water quality. Concentrations are higher in wells that are shallower, older, dug, or driven; located close to cropland, feedlots, or chemical mixing sites; or located in sandy soils. Where wells combine the most vulnerable alternative for two or three factors, the probability of contamination increases dramatically. Mapping sometimes reveals spatial patterns of contamination that reflect geological influences. River valley aquifers, sandy soils with high water tables, karst areas, and reef structures with surficial expressions are all reflected in county maps of the data.

Comprehensive State Ground Water Protection Programs: A Preliminary Examination of Two States

Comprehensive State Ground Water Protection Programs: A Preliminary Examination of Two States

Delineation of Wellhead Protection Areas: Theory and Practice

A preventive approach in groundwater protection programs throughout Europe and the United States, and almost unknown in Brazil, is to define the surface and subsurface areas, the Wellhead Protection Area (WHPA), from which a well or wellfield draws its water during a specified time. Overlaying a map of potential pollution sources on the delineated WHPA (Figure 1), those sources which fall within the WHPA boundaries are identified as definite threats, that need to be closely monitored, to the continued safe operation of the wellfield. Given the importance of effectively delineating the WHPA to protect public water supplies, the current delineation criteria, methods, and zones are presented, as well as analytical and numerical PC model analyses of different hydrogeological scenarios' effects on WHPA's size, shape and direction. Numerical models are shown to more accurately define WHPAs by taking into account the surrounding heterogeneous and anisotropic geology.

Groundwater Use and Protection in the Petrochemical Complex Region, Camaçari, Bahia, Brazil

The Petrochemical Complex Region (COPEC) is located on the top of a huge aquifer (10,000 km2, with average thickness of 600m), chiefly composed of undifferentiated deposits of coarse to fine sands and gravels with lenses of interbedded silts and clays. This paper provides an overview of the problems, and proposes the data and organization requirements for developing a local groundwater protection program. The freshwater reserves (120 billion m3 and global groundwater flow to rivers of 3 billion m3/yr) may be considered a resource of unusually high value. The issue of contamination with Synthetic Organic Chemicals (SOCs) and toxic metals was first raised during the mid 1980s. This poses significant water quality problems and imposes special restrictions on the industrial development in this area, mostly because few high-quality alternative sources of drinking water remain in proximity to a human population of 3.5 million people. The policy of neglect cannot be continued without grave threats to human health.

Pesticides pollution of groundwater in the humid United States

Since 1980, many studies have begun to look at the occurrence of pesticides in groundwater; these range from controlled field/plot research studies, to simple monitoring of public water supplies to assess the occurrence of pesticides. The compounds most commonly detected are: (1) mobile and/or volatile soil fumigants and nematicides, used on vegetable or specialty crops; (2) commonly used herbicides from the humid corn-belt regions. The fumigants-nematicides have been the most widely looked for compounds. The herbicides commonly detected are also some of the most widely used of all pesticides, but pesticide properties clearly affect how commonly they are detected. In nearly all corn-belt areas, the herbicide atrazine is the most commonly detected compound. A general overview shows that a total of 39 pesticides have been detected in groundwater from 34 states or provinces. This includes occurrences related to commercial point sources (but not manufacturing sites, or detections exclusively referred to commercial sources) as well as nonpoint sources. From states with appropriate studies, there appears, within the context of pesticide properties, some general proportionality between pesticide use and detections in groundwater; this is also confounded by climatic differences. Kansas studies suggest that 8–10% of private, rural drinking-water supply wells, and 10% of susceptible public water-supply wells may exhibit pesticide contamination. Surveys in Minnesota and Iowa, with more intensive pesticide usage suggest that 20–30% of the more susceptible public water-supply wells, and 30–60% of private wells may exhibit pesticide residues. In contrast however, Illinois, a very high use state, has detected few pesticides in public water-supply wells (except where related to a commercial point source); why such differences occur among adjacent states is not clear. Pesticides are leaching through the soil and into groundwater far more commonly than the preconceptions of a decade ago would have predicted. Point sources may be widespread but are not the sole cause; it is also clear that many pesticides are leaching to groundwater from routine, nonpoint source use. Controlled plot studies show the intermittent, often rapid delivery of many pesticides to shallow groundwaters. The preferential flow of water and solutes through soil and rock materials clearly contributes to the delivery of pesticides to groundwater. The occurrence of preferential flow also implies that notions about the ‘relative susceptibility’ of various soils to pesticide leaching may not be accurate. Some studies show pesticide leaching more commonly in finer-textured soils than coarser, sandy textured soils. Generally, the concentrations of pesticides in groundwater are low, in the 0.1–5.0 μg l −1 range. Even at these concentrations there are concerns for long-term, chronic exposure to a large segment of the public through drinking-water supplies. While concerns with groundwater merit attention, the concentrations of pesticides in drinking water derived from surface waters will typically be greater. Current policy discussions often fail to understand the difference between groundwater protection and drinking-water protection programs and may not provide adequate protection for private rural groundwater supplies. Research and policies to resolve the problems of agricultural impacts on the environment will require a new focus on integrated farm-management systems, that enhance efficiency and reduce off-site impacts.

Record budgets for groundwater

A record $225 million is expected to be allocated for management of the nation's groundwater resources for the 1990 budget year by federal funds. The recent report by the White House Office of Science and Technology, Federal Ground‐Water Science and Technology Programs: The Role of Science and Technology in the Management of the Nation's Ground‐Water Resources, noted, “As the demands on the water resources of the nation increase, there will be an increasing need to apply the science of groundwater hydrology to find ways to provide reliable water supplies.”The report identifies emerging scientific issues and needs and the major challenges faced in providing science and technology to support informed management of the nation's groundwater resources. In particular, the report notes that the most viable approach to groundwater quality management is prevention rather than restoration and that that scientific uncertainties, lack of adequate technologies, lack of basic data, and shortage of skilled scientific personnel are hindrances to federal, state, and local governments and the private sector developing and implementing groundwater management, protection, and remediation policies and programs.

Pesticide Bill Faces Difficulties in Senate

Legislation providing for the first major overhaul of the law governing the sale and use of pesticides since 1978 has cleared the House easily. When it was reported out by the House Agriculture Committee in June, H.R. 2482—Federal Insecticide, Fungicide & Rodenticide Act Amendments of 1986, was supported by both the agricultural chemical industry and environmental, consumer, farm, and labor organizations. However, some controversial amendments adopted by the full House have shaken that coalition and may jeopardize the bill's chances of passing the Senate. Industry is not pleased by an amendment that would make the registrant of a pesticide—that is, the manufacturer—responsible for cleaning up any environmental damages caused by the product's use, unless the applicator acted negligently, recklessly, or with intent to misuse the pesticide. Nor does industry like an amendment that, in addition to setting up a new groundwater protection program, gives the Energy & Commerce Committee, rather than the Agricultu...

Regulatory Focus: Groundwater protection programs

Regulatory Focus: Groundwater protection programs

Drinking Water Bill Sails Through Congress

It's been a long 17-month haul, but two weeks ago the 99th Congress passed its first major environmental legislation—a bill that strengthens the Safe Drinking Water Act. The conference bill literally sailed through Congress, passing the House May 13 by a vote of 382 to 21 and the Senate May 21 by a vote of 94 to 0. The bill, which authorizes vast increases in spending for drinking water programs through 1991, was sent to the President for his approval. A Presidential veto is possible but not considered likely. The Environmental Protection Agency in the past has expressed concern about some key provisions of the bill, mainly the new groundwater protection program. But an EPA spokesman says the agency is reviewing the conference bill before it makes its final recommendation to the President. Groundwater protection is the major new thrust of revisions to the drinking water act. Another key provision is a requirement that EPA ...

NRC evaluates groundwater programs

A recent report by the National Research Council (NRC) noted that about half the people of the United States depend on wells for their drinking water, but recent tests reveal widespread contamination.Responsibility for monitoring and protecting groundwater supplies lies largely with state governments. Federal funding of model projects under the Clean Water Act expired in 1983. However, the U.S. Environmental Protection Agency (EPA) has asked the NRC to identify and evaluate ten state and local groundwater protection programs and to recommend features that may be applied in other areas. A committee, organized by the Water Science and Technology Board and chaired by Jerome B. Gilbert, general manager of the East Bay Municipal Utility District of Oakland, Calif., has undertaken the study. The report is expected to be completed in March 1986.