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Sample records for morroa aquifer colombia

  1. Hydraulic characterization of the heterogeneity of the "Valle del Cauca" Aquifer (Colombia)

    NASA Astrophysics Data System (ADS)

    Donado, L. D.; Gomez-Español, A.

    2012-04-01

    This research consists of a regional study in which is analyzed and defined in detail the response of a large alluvial aquifer to external imposed stresses of varying magnitude at multiple points within its area. On the other hand, this work evaluates and establishes the spatial correlation structure of the transmissivity and specific capacity values and provides a spatial stochastic prediction model. The later acceptably synthesizes the field properties of each of these parameters. The prediction model was developed from the cross correlation between 852 series values of specific capacity and 316 from transmissivity. This model lead us to demonstrate from the geological perspective that exits a relation among geomorphology and recharge areas so that, higher transmissivity values are presented in the lowlands of the valley through which rivers flow localized in recharge areas generated by geological folds. Since 1950, began an intensive development of this aquifer (Colombia). Despite the country has a positive water balance (IDEAM, 2003), this aquifer is the most productive one in Colombia, has an extension of 3,300 km2. Approximately 1,500 wells supply about 92,540 L/s used for agricultural and industrial purposes. This research uses about 1,000 pumping tests carried out since 1970 by the regional environmental agency (CVC). We interpreted those pumping tests using the diagnostic plot method (Rennard, 2008) to determine aquifer transmissivity and specific capacity. The model figures out a significant geological heterogeneity in the apparently homogeneous alluvial aquifer that leads us to use several interpretation methods for different boundary and well conditions. This brings into question the validity of the regional scale research using a single method of interpretation. Similarly, the results permit us to review the current conceptual model of a three layers aquifer (unconfined - aquitard - confined aquifers) with a defined thickness to a heterogeneous model

  2. Colombia.

    PubMed

    1986-10-01

    This report of background notes for Colombia concentrates on political history, but also summarizes geography, people, economy, defense and foreign relations. Colombia, linking Panama to the northwest tip of South America, has 26.5 million people, growing at 1.3% per year, expected to be the third most populous nationon the continent soon. Infant mortality rate is 65/1000 and life expectancy is 62 years. Literacy is reported at 80% although less than 40% of children complete 2.5 years of school. Geographically, Colombia has flat coastal areas, several mountain ranges, highlands and hot eastern plains. 70% of the population live in cities. There are 2 major political parties, in existence since the early 19th century. Recently there have been violent inter-party differences, punctuated by even more contentious guerrilla attacks. Colombia possesses resources of oil, gas coal, nickel, gold, emeralds, platinum, iron. Agricultural products are dominated by coffee, but also include a wide variety of tropical and temperate grains, fruits, vegetables, dairy and meat products, timber and flowers. PMID:12177933

  3. Carbonate aquifers

    USGS Publications Warehouse

    Cunningham, Kevin J.; Sukop, Michael; Curran, H. Allen

    2012-01-01

    Only limited hydrogeological research has been conducted using ichnology in carbonate aquifer characterization. Regardless, important applications of ichnology to carbonate aquifer characterization include its use to distinguish and delineate depositional cycles, correlate mappable biogenically altered surfaces, identify zones of preferential groundwater flow and paleogroundwater flow, and better understand the origin of ichnofabric-related karst features. Three case studies, which include Pleistocene carbonate rocks of the Biscayne aquifer in southern Florida and Cretaceous carbonate strata of the Edwards–Trinity aquifer system in central Texas, demonstrate that (1) there can be a strong relation between ichnofabrics and groundwater flow in carbonate aquifers and (2) ichnology can offer a useful methodology for carbonate aquifer characterization. In these examples, zones of extremely permeable, ichnofabric-related macroporosity are mappable stratiform geobodies and as such can be represented in groundwater flow and transport simulations.

  4. MAINE AQUIFERS

    EPA Science Inventory

    AQFRS24 contains polygons of significant aquifers in Maine (glacial deposits that are a significant ground water resource) mapped at a scale 1:24,000. This statewide coverage was derived from aquifer boundaries delineated and digitized by the Maine Geological Survey from data com...

  5. Trinity Gas to explore for gas in Colombia

    SciTech Connect

    1997-07-01

    Trinity Gas Corp. officials signed an agreement on May 20, 1997, with the Cauca Valley Corp. (CVC) allowing Trinity to use CVC data to explore for natural gas in the Cauca Valley of Colombia. CVC, Colombia`s Valle del Cauca water resources and environmental division, is evaluating Colombia`s underground water reserves to protect, control and preserve fresh water aquifers, some of which contain natural gas pockets that cause blowouts in farmers` water wells. Preparations now are underway for drilling Trinity`s first well at the Palmira 1 site on the San Jose Hacienda, the largest privately owned sugar cane plantation in the valley. Trinity also entered into an agreement with the Cauca Valley Natural Gas and Electricity Project to furnish natural gas, generated electricity and energy fuel for the industrial district in the region. According to this contract, many valley residents will have electric service for the first time.

  6. AQUIFER TRANSMISSIVITY

    EPA Science Inventory

    Evaluation of groundwater resources requires the knowledge of the capacity of aquifers to store and transmit ground water. This requires estimates of key hydraulic parameters, such as the transmissivity, among others. The transmissivity T (m2/sec) is a hydrauli...

  7. Education in Colombia.

    ERIC Educational Resources Information Center

    Renner, Richard R.

    As one of the more traditional Latin American societies, Colombia's educational policies have been affected by long-standing cultural beliefs including class values and social stratification. This paper examines the educational history of Colombia, provides a thorough background on its educational achievements and difficulties, and discusses…

  8. Dental education in Colombia

    PubMed Central

    Jaramillo, Jorge A.; Pulido, Jairo H. Ternera; Núñez, Jaime A. Castro; Bird, William F.; Komabayashi, Takashi

    2014-01-01

    This article describes Colombia's development of formal dentistry, its dental school system, curriculum, and dental licensure, and current issues in oral health care. In 1969, there were only 4 dental schools in Colombia; at this writing there are 21. Five dental schools are public and the other 16 are private. Nearly all classes are conducted in Spanish. Undergraduate pre-dental coursework is not a prerequisite for dental school in Colombia. To obtain licensure, Colombian dental students must complete 5 years of study in dental school, earn a diploma, and work for the government for 1 year. There are approximately 41,400 dentists in Colombia, and the number is increasing quickly. However, the unemployment rate among dentists is very high, even though graduation from dental school is extremely difficult. Although the 1,100:1 ratio of citizens to dentists is considered satisfactory, access to dental care is limited due to the high rate of poverty. PMID:20339245

  9. Terrorism in Colombia.

    PubMed

    Paredes Zapata, Gabriel Darío

    2003-01-01

    Colombia is a poor country that has been plagued by ongoing violence for more than 120 years. During the 1940s, subversive terrorist groups emerged in rural areas of the country when criminal groups came under the influence of Communism, and were later transformed into contemporary groups, such as the Ejercito de Liberacion Nacional (ELN) or National Liberation Army and Fuerzas Armadas Revolucionares de Colombia (FARC) or Revolutionary Armed Forces of Colombia). Paramilitary terrorist groups emerged in response to subversive groups and were later transformed into contemporary groups, such as the Autodefensas Unidas de Colombia (AUC) or United Self-Defense Forces of Colombia. Terrorism has placed an enormous burden on modern Colombia. From 1995 to 2002, 9,435 people were killed by terrorism-related events, of which 5,864 were killed by subversive terrorist activities and 3,571 were killed by paramilitary terrorist activities. In 2002, at least nineteen attacks produced 10 or more casualties, of which 18 were bombings. In 2002, terrorists killed at least 12 mayors, 71 legislators, and internally displaced 300,000 persons from their homes. Since terrorist groups in Colombia are typically supported by drug manufacturing and trafficking, it has been difficult at times to distinguish violence due to terrorism from violence due to illicit drug trafficking. Terrorism has also had a major adverse effect on the economy, with restricted travel, loss of economic resources, and lack of economic investment. In addition to political, military, and commercial targets, terrorists have specifically targeted healthcare infrastructure and personnel. At the national and local levels, much emergency planning and preparedness has taken place for terrorism-related events. The Centro Regulador de Urgencias (CRU) or Emergency Regulation Center in Bogota plays a major role in coordinating local prehospital and hospital emergency response in the capital city and the national level where

  10. Aquifer-nomenclature guidelines

    USGS Publications Warehouse

    Laney, R.L.; Davidson, C.B.

    1986-01-01

    Guidelines and recommendations for naming aquifers are presented to assist authors of geohydrological reports in the United States Geological Survey, Water Resources Division. The hierarchy of terms that is used for water- yielding rocks from largest to smallest is aquifer system, aquifer, and zone. If aquifers are named, the names should be derived from lithologic terms, rock-stratigraphic units, or geographic names. The following items are not recommended as sources of aquifer names: time-stratigraphic names, relative position, alphanumeric designations, depositional environment, depth of occurrence, acronyms, and hydrologic conditions. Confining units should not be named unless doing so clearly promotes understanding of a particular aquifer system. Sources of names for confining units are similar to those for aquifer names, i.e. lithologic terms, rock-stratigraphic units or geographic names. Examples of comparison charts and tables that are used to define the geohydrologic framework are included. Aquifers are defined in 11 hypothetical examples that characterize geohydrologic settings throughout the country. (Author 's abstract)

  11. Recruiting Teachers in Colombia

    ERIC Educational Resources Information Center

    Blair, Robert

    2009-01-01

    In this article, the author talks about a system of special schools in Colombia which introduces students to teaching careers as early as the 8th grade. The Colombian system is based on a simple idea: Every student is a potential teacher. Principals talk about molding "ciudadano-pedagogos"--citizen-educators who view teaching as a way of…

  12. English Teaching Profile: Colombia.

    ERIC Educational Resources Information Center

    British Council, London (England). English Language and Literature Div.

    A review of the status of English language instruction in Colombia provides an overview of the role of English in the society in general and outlines the status of English use and instruction in the educational system at all levels (elementary, secondary, postsecondary, and teacher education). The following topics are covered: the characteristics…

  13. English Teaching Profile: Colombia.

    ERIC Educational Resources Information Center

    British Council, London (England). English Language and Literature Div.

    This profile of the English language teaching situation in Colombia discusses the role of English in the educational system and in Colombian society. The status of English as the country's first foreign language is examined. It is noted that because Spanish is sufficient for most needs and because there is a relatively small number of Colombians…

  14. Biscayne aquifer, southeast Florida

    USGS Publications Warehouse

    Klein, Howard; Hull, John E.

    1978-01-01

    Peak daily pumpage from the highly permeable, unconfined Biscayne aquifer for public water-supply systems in southeast Florida in 1975 was about 500 million gallons. Another 165 million gallons was withdrawn daily for irrigation. Recharge to the aquifer is primarily by local rainfall. Discharge is by evapotranspiration, canal drainage, coastal seepage, and pumping. Pollutants can enter the aquifer by direct infiltration from land surface or controlled canals, septic-tank and other drainfields, drainage wells, and solid-waste dumps. Most of the pollutants are concentrated in the upper 20 to 30 feet of the aquifer; public supply wells generally range in depth from about 75 to 150 feet. Dilution, dispersion, and adsorption tend to reduce the concentrations. Seasonal heavy rainfall and canal discharge accelerate ground-water circulation, thereby tending to dilute and flush upper zones of the aquifer. The ultimate fate of pollutants in the aquifer is the ocean, although some may be adsorbed by the aquifer materials en route to the ocean, and some are diverted to pumping wells. (Woodard-USGS)

  15. Identifying aquifer type in fractured rock aquifers using harmonic analysis.

    PubMed

    Rahi, Khayyun A; Halihan, Todd

    2013-01-01

    Determining aquifer type, unconfined, semi-confined, or confined, by drilling or performing pumping tests has inherent problems (i.e., cost and complex field issues) while sometimes yielding inconclusive results. An improved method to cost-effectively determine aquifer type would be beneficial for hydraulic mapping of complex aquifer systems like fractured rock aquifers. Earth tides are known to influence water levels in wells penetrating confined aquifers or unconfined thick, low-porosity aquifers. Water-level fluctuations in wells tapping confined and unconfined aquifers are also influenced by changes in barometric pressure. Harmonic analyses of water-level fluctuations of a thick (~1000 m) carbonate aquifer located in south-central Oklahoma (Arbuckle-Simpson aquifer) were utilized in nine wells to identify aquifer type by evaluating the influence of earth tides and barometric-pressure variations using signal identification. On the basis of the results, portions of the aquifer responded hydraulically as each type of aquifer even though there was no significant variation in lithostratigraphy. The aquifer type was depth dependent with confined conditions becoming more prevalent with depth. The results demonstrate that harmonic analysis is an accurate and low-cost method to determine aquifer type. PMID:22463080

  16. Education for a New Colombia.

    ERIC Educational Resources Information Center

    Renner, Richard R.

    This study, one of a series of publications on education in other countries, describes all major levels and types of education in Colombia against a background of the relevant economic, cultural, and social features of that country. The first two chapters depict features of Colombia essential to understanding the context within which its…

  17. Child health in Colombia.

    PubMed

    Nieto, G Arias; Mutis, F Suescun; Mercer, R; Bonati, M; Choonara, I

    2009-11-01

    Colombia is a country with major problems, mainly a high degree of inequality and an unacceptably high level of violence (both armed military conflict and crime related). There are unacceptably high variations in health and health provision. Despite these difficulties, there are important steps being taken by both the government and independent organisations to try and improve child health and to achieve the Millennium Development Goals in relation to poverty, hunger and health issues. The participation of different sectors and stakeholders (including government, non-governmental organisations and other organisations of civil society) is essential to overcome Colombian history and to promote a better place for children. PMID:19586926

  18. 40 CFR 147.2908 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.2908 Section...-Class II Wells § 147.2908 Aquifer exemptions. (a) After notice and opportunity for a public hearing, the Administrator may designate any aquifer or part of an aquifer as an exempted aquifer. (b) An aquifer or...

  19. 40 CFR 147.2908 - Aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.2908 Section...-Class II Wells § 147.2908 Aquifer exemptions. (a) After notice and opportunity for a public hearing, the Administrator may designate any aquifer or part of an aquifer as an exempted aquifer. (b) An aquifer or...

  20. 40 CFR 147.2908 - Aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.2908 Section...-Class II Wells § 147.2908 Aquifer exemptions. (a) After notice and opportunity for a public hearing, the Administrator may designate any aquifer or part of an aquifer as an exempted aquifer. (b) An aquifer or...

  1. 40 CFR 147.2908 - Aquifer exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.2908 Section...-Class II Wells § 147.2908 Aquifer exemptions. (a) After notice and opportunity for a public hearing, the Administrator may designate any aquifer or part of an aquifer as an exempted aquifer. (b) An aquifer or...

  2. 40 CFR 147.2908 - Aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.2908 Section...-Class II Wells § 147.2908 Aquifer exemptions. (a) After notice and opportunity for a public hearing, the Administrator may designate any aquifer or part of an aquifer as an exempted aquifer. (b) An aquifer or...

  3. IDAHO AQUIFER TYPES

    EPA Science Inventory

    Five aquifer types are presented: Unconsolidated alluvium, Snake River Plain alluvium, Snake River Plain basalt, Columbia River basalt, Sedimentary / volcanic rock. Should only be used for page-sized maps of state, due to the very generalized source materials & digitizing proce...

  4. Inquiry and Aquifers.

    ERIC Educational Resources Information Center

    Leuenberger, Ted; Shepardson, Daniel; Harbor, Jon; Bell, Cheryl; Meyer, Jason; Klagges, Hope; Burgess, Willie

    2001-01-01

    Presents inquiry-oriented activities that acquaint students with groundwater sources, movement of water through aquifers, and contamination of groundwater by pollution. In one activity, students use well log data from web-based resources to explore groundwater systems. Provides sample well log data for those not having access to local information.…

  5. EPA - NEW ENGLAND SOLE SOURCE AQUIFERS

    EPA Science Inventory

    This coverage contains boundaries of EPA-approved sole source aquifers. Sole source aquifers are defined as an aquifer designated as the sole or principal source of drinking water for a given aquifer service area; that is, an aquifer which is needed to supply 50% or more of the ...

  6. Land Reform and Social Change in Colombia.

    ERIC Educational Resources Information Center

    Hirschman, Albert O.; And Others

    This conference report focuses on three major areas of interest: (1) land reform in Colombia, (2) social change in Popayan, and (3) implications for research in agrarian structure in Colombia. A case study dealing with Colombia's sequence of moves toward land reform over the last 40 years is reviewed. The impact of political factors and social…

  7. Discoveries, financial strength lift Colombia

    SciTech Connect

    Koen, A.D.

    1996-07-15

    Colombia plans to play a growing role in international oil markets while expanding and privatizing its domestic gas and electricity industries. Officials intend to curb the government`s spending on energy development while increasing its energy revenues. Their plans imply growing participation in energy projects by private companies. Also certain to help attract investment capital is the country`s new standing as a world-class oil and gas province. Discovery of Cusiana oil field in 1989 and of Cupiagua oil field in 1992 added 2 billion bbl of oil and 3 tcf of gas reserves, effectively doubling Colombia`s totals. Exploration near the giant Cusiana-Cupiagua complex, in the eastern foothills of the Andes about 100 miles northeast of Bogota, has turned up an estimated 10 tcf of gas and 1 billion bbl of oil in Volcanera field and two discoveries overlying it, Florena and Pauto Sur. Colombia`s critics say that, despite its laudable economic stability and improving oil and gas prospectivity, political impediments could interfere with progress toward its lofty energy goals. The paper discusses the heightened political risks, unequal pace of reform, gas pipeline construction, gas regulations, tying gas to power, reform in the oil sector, achieving sustainable change, and the appeal to investors.

  8. The Colombia Seismological Network

    NASA Astrophysics Data System (ADS)

    Blanco Chia, J. F.; Poveda, E.; Pedraza, P.

    2013-05-01

    The latest seismological equipment and data processing instrumentation installed at the Colombia Seismological Network (RSNC) are described. System configuration, network operation, and data management are discussed. The data quality and the new seismological products are analyzed. The main purpose of the network is to monitor local seismicity with a special emphasis on seismic activity surrounding the Colombian Pacific and Caribbean oceans, for early warning in case a Tsunami is produced by an earthquake. The Colombian territory is located at the South America northwestern corner, here three tectonic plates converge: Nazca, Caribbean and the South American. The dynamics of these plates, when resulting in earthquakes, is continuously monitored by the network. In 2012, the RSNC registered in 2012 an average of 67 events per day; from this number, a mean of 36 earthquakes were possible to be located well. In 2010 the network was also able to register an average of 67 events, but it was only possible to locate a mean of 28 earthquakes daily. This difference is due to the expansion of the network. The network is made up of 84 stations equipped with different kind of broadband 40s, 120s seismometers, accelerometers and short period 1s sensors. The signal is transmitted continuously in real-time to the Central Recording Center located at Bogotá, using satellite, telemetry, and Internet. Moreover, there are some other stations which are required to collect the information in situ. Data is recorded and processed digitally using two different systems, EARTHWORM and SEISAN, which are able to process and share the information between them. The RSNC has designed and implemented a web system to share the seismological data. This innovative system uses tools like Java Script, Oracle and programming languages like PHP to allow the users to access the seismicity registered by the network almost in real time as well as to download the waveform and technical details. The coverage

  9. Renal disease in Colombia.

    PubMed

    Gómez, Rafael Alberto

    2006-01-01

    Chronic renal disease represents a problem of public health in Colombia. Its prevalence has increased in last decade, with a prevalence of 44.7 patients per million (ppm) in 1993 to 294.6 ppm in 2004, considering that only 56.2% of the population has access to the health. This increase complies with the implementation of Law 100 of 1993, offering greater coverage of health services to the Colombian population. The cost of these pathologies is equivalent to the 2.49% of the budget for health of the nation. The three most common causes of renal failure are diabetes mellitus (DM; 30%), arterial hypertension (30%), and glomerulonephritis (7.85%). In incident patients, the DM accounts for 32.9%. The rate of global mortality is 15.8%, 17.4% in hemodialysis and 15.1% in peritoneal dialysis. In 2004, 467 renal transplants were made, 381 of deceased donor with an incidence of 10.3 ppm. The excessive cost of these pathologies can cause the nation's health care system to collapse if preventative steps are not taken. In December of 2004, the Colombian Association of Nephrology with the participation of the Latin American Society of Nephrology and Arterial Hypertension wrote the "Declaration of Bogotá," committing the state's scientific societies and promotional health companies to develop a model of attention for renal health that, in addition to implementing national registries, continues to manage renal disease. PMID:17162422

  10. Mantidflies of Colombia (neuroptera, mantispidae).

    PubMed

    Ardila-Camacho, Adrian; García, Alexander

    2015-01-01

    This study revises the Mantispidae of Colombia. 151 adult specimens of 12 entomological museums of Colombia were examined and identified. On the basis of the specimens studied and a comprehensive literature search, it is determined that 20 nominal species (including two doubtful records) plus four proposed as new to science, in ten genera (Anchieta, Plega, Trichoscelia, Gerstaeckerella, Buyda, Climaciella, Dicromantispa, Entanoneura, Leptomantispa, and Zeugomantispa) and, three subfamilies (Symphrasinae, Drepanicinae, and Mantispinae) occur in Colombia. In addition, A. eurydella (Westwood), C. amapaensis Penny and P. fasciatella (Westwood) are redescribed, providing complementary information to the original descriptions. A list of Colombian Mantispidae, distribution maps and taxonomic keys to subfamilies, genera and species are included. Illustrations of the external morphology and male genitalia are provided for selected species. The taxonomic status of P. hagenella (Westwood) is discussed, and its diagnostic characters are redefined. Anchieta remipes (Gerstaecker) is newly transferred to this genus from Trichoscelia. PMID:25947479

  11. Renewable energy potential in Colombia

    NASA Astrophysics Data System (ADS)

    Correa Guzman, Jose Luis

    2008-12-01

    Renewable energy flows are very large in comparison with humankind's use of energy. In principle, all our energy needs, both now and into the future, can be met by energy from renewable sources. After many years trying to develop the alternative energy potential of Colombia, a major effort is principally being made since 2000 to explore and assess the renewable resources of the entire country. Until 2000, the availability of conventional energy sources in Colombia prevented renewable energy exploration from reaching a higher level. However, the extreme energy crisis of 1992 - 1993 alerted the authorities and the community to the necessity for exploring alternative energy sources. This energy study is a general approach to the current and future renewable energy scenario of Colombia. It was prepared in response to the increased interest around the world and in particular in Colombia to develop its non-fossil energy prospective. It, therefore, represents a working document giving an initial impression of the possible scale of the main renewables sources as a response to the concern about energy security and fossil fuel dependence problems. The assumptions made and calculations reported may therefore be subject to revision as more information becomes available. The aim of this dissertation is not only to improve the public understanding and discussion of renewable energy matters in Colombia but also to stimulate the development and application of renewable energy, wherever they have prospects of economic viability and environmental acceptability. To achieve such goal this paper reviews several renewable technologies, their availability, contribution and feasibility in Colombia.

  12. High Temperature Aquifer Storage

    NASA Astrophysics Data System (ADS)

    Ueckert, Martina; Niessner, Reinhard; Baumann, Thomas

    2016-04-01

    Combined heat and power generation (CHP) is highly efficient because excess heat is used for heating and/or process energy. However, the demand of heat energy varies considerably throughout the year while the demand for electrical energy is rather constant. It seems economically and ecologically highly beneficial for municipalities and large power consumers such as manufacturing plants to store excess heat in groundwater aquifers and to recuperate this energy at times of higher demand. Within the project High Temperature Aquifer Storage, scientists investigate storage and recuperation of excess heat energy into the bavarian Malm aquifer. Apart from high transmissivity and favorable pressure gradients, the hydrochemical conditions are crucial for long-term operation. An enormous technical challenge is the disruption of the carbonate equilibrium - modeling results indicated a carbonate precipitation of 10 - 50 kg/d in the heat exchangers. The test included five injection pulses of hot water (60 °C up to 110 °C) and four tracer pulses, each consisting of a reactive and a conservative fluorescent dye, into a depth of about 300 m b.s.l. resp. 470 m b.s.l. Injection and production rates were 15 L/s. To achieve the desired water temperatures, about 4 TJ of heat energy were necessary. Electrical conductivity, pH and temperature were recorded at a bypass where also samples were taken. A laboratory container at the drilling site was equipped for analysing the concentration of the dyes and the major cations at sampling intervals of down to 15 minutes. Additional water samples were taken and analysed in the laboratory. The disassembled heat exchanger prooved that precipitation was successfully prevented by adding CO2 to the water before heating. Nevertheless, hydrochemical data proved both, dissolution and precipitation processes in the aquifer. This was also suggested by the hydrochemical modelling with PhreeqC and is traced back to mixture dissolution and changing

  13. High Temperature Aquifer Storage

    NASA Astrophysics Data System (ADS)

    Ueckert, Martina; Niessner, Reinhard; Baumann, Thomas

    2015-04-01

    Combined heat and power generation (CHP) is highly efficient because excess heat is used for heating and/or process energy. However, the demand of heat energy varies considerably throughout the year while the demand for electrical energy is rather constant. It seems economically and ecologically highly beneficial for municipalities and large power consumers such as manufacturing plants to store excess heat in groundwater aquifers and to recuperate this energy at times of higher demand. Apart from the hydrogeological conditions, high transmissivity and favorable pressure gradients, the hydrochemical conditions are crucial for long-term operation. Within the project High Temperature Aquifer Storage, scientists investigate storage and recuperation of excess heat energy into the bavarian Malm aquifer. After one year of planning, construction, and the successful drilling of a research well to 495 m b.s.l. the first large scale heat storage test in the Malm aquifer was finished just before Christmas 2014. An enormous technical challenge was the disruption of the carbonate equilibrium - modeling results indicated a carbonate precipitation of 10-50 kg/d in the heat exchangers. The test included five injection pulses of hot water (60 °C up to 110 °C) and four tracer pulses, each consisting of a reactive and a conservative fluorescent dye. Injection and production rates were 15 L/s. About 4 TJ of heat energy were necessary to achieve the desired water temperatures. Electrical conductivity, pH and temperature were recorded at a bypass where also samples were taken. A laboratory container at the drilling site was equipped for the analysis of the concentration of the tracers and the cation concentrations at sampling intervals of down to 15 minutes. Additional water samples were taken and analyzed for major ions and trace elements in the laboratory. The disassembled heat exchanger proved that precipitation was successfully prevented by adding CO2 to the water before heating

  14. Colombia. America = Las Americas [Series].

    ERIC Educational Resources Information Center

    Toro, Leonor; Doran, Sandra

    Written for teachers to use with migrant children in elementary grades to highlight the many Americas, this bilingual English/Spanish social studies resource booklet provides historical and cultural background information on Colombia and features biographies of Colombian leaders and artists. A table of contents indicates the language--Spanish or…

  15. Biblored, Colombia's Innovative Library Network.

    ERIC Educational Resources Information Center

    Caballero, Maria Cristina

    This report describes Biblored, the library network in Bogota, Colombia, that received the 2002 Bill & Melinda Gates Foundation Access to Learning Award. Biblored is a network of 19 libraries that attract about 200,000 users per month and serve some of the poorest neighborhoods in Bogota. The network's success in making information and information…

  16. Bogota--Colombia's thriving capital.

    PubMed

    Hakkert, R

    1987-05-01

    Like most of its Latin American counterparts, Colombia is rapidly urbanizing. Home to 20% of Colombia's urban population and the largest industrial agglomeration in the nation, Bogota shares its dominance with several other large Colombian cities. Projections compiled from the 1973 census--the latest census available-- project the 1980 population of Bogota at 4 to 5.1 million. Government estimates peg Bogota's 1990 population at 8.5 million people. Most of Bogota's best neighborhoods now lie to the north of the city. On the whole, housing contrasts in Bogota are not as stark as in some other Latin American cities, although the estimated 1980 housing deficit of 210,000 units led to significant self-help construction. Women have made dramatic in-roads into equalizing educational attainment with men. Among the city's most important problems is unemployment. Completed family size in Bogota has plummeted since the inception of family planning programs in the early 1960s. Between 1956 and 1973, Colombia's per capita income increased by about 45%, but the increase was more rapid in Bogota, where per capita incomes in 1970 were about 60% higher than the national average. Much of the current in-depth data on Bogota comes from the World Bank research project known as the City Study. Much of the data in this profile of Bogota came from the analysis of this survey data, presented in World Bank Research publications. Rather than from Colombia's last census of 1973. PMID:12341327

  17. 40 CFR 147.102 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.102 Section... Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  18. 40 CFR 147.302 - Aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.302 Section... Aquifer exemptions. (a) This section identifies any aquifers of their portions exempted in accordance with... other aquifers or portions according to applicable procedures without codifying such exemptions in...

  19. 40 CFR 147.3003 - Aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.3003 Section..., Ute Mountain Ute, and All Other New Mexico Tribes § 147.3003 Aquifer exemptions. (a) Aquifer... described in appendix A are hereby exempted. The exempted aquifers are defined by a one-quarter mile...

  20. 40 CFR 147.2554 - Aquifer exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.2554 Section... Aquifer exemptions. In accordance with §§ 144.7(b) and 146.4 of this chapter, those portions of aquifers... injection activity. This exemption applies only to the aquifers tabulated below, and includes those...

  1. 40 CFR 147.102 - Aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.102 Section... Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  2. 40 CFR 147.2554 - Aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.2554 Section... Aquifer exemptions. In accordance with §§ 144.7(b) and 146.4 of this chapter, those portions of aquifers... injection activity. This exemption applies only to the aquifers tabulated below, and includes those...

  3. 40 CFR 147.302 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.302 Section... Aquifer exemptions. (a) This section identifies any aquifers of their portions exempted in accordance with... other aquifers or portions according to applicable procedures without codifying such exemptions in...

  4. 40 CFR 147.2102 - Aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.2102 Section....2102 Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in... future exempt other aquifers or their portions, according to applicable procedures, without...

  5. 40 CFR 147.2102 - Aquifer exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.2102 Section....2102 Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in... future exempt other aquifers or their portions, according to applicable procedures, without...

  6. 40 CFR 147.3003 - Aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.3003 Section..., Ute Mountain Ute, and All Other New Mexico Tribes § 147.3003 Aquifer exemptions. (a) Aquifer... described in appendix A are hereby exempted. The exempted aquifers are defined by a one-quarter mile...

  7. 40 CFR 147.1952 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1952 Section....1952 Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in... future exempt other aquifers or portions, according to applicable procedures, without codifying...

  8. 40 CFR 147.3003 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.3003 Section..., Ute Mountain Ute, and All Other New Mexico Tribes § 147.3003 Aquifer exemptions. (a) Aquifer... described in appendix A are hereby exempted. The exempted aquifers are defined by a one-quarter mile...

  9. 40 CFR 147.2554 - Aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.2554 Section... Aquifer exemptions. In accordance with §§ 144.7(b) and 146.4 of this chapter, those portions of aquifers... injection activity. This exemption applies only to the aquifers tabulated below, and includes those...

  10. 40 CFR 147.302 - Aquifer exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.302 Section... Aquifer exemptions. (a) This section identifies any aquifers of their portions exempted in accordance with... other aquifers or portions according to applicable procedures without codifying such exemptions in...

  11. 40 CFR 147.2554 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.2554 Section... Aquifer exemptions. In accordance with §§ 144.7(b) and 146.4 of this chapter, those portions of aquifers... injection activity. This exemption applies only to the aquifers tabulated below, and includes those...

  12. 40 CFR 147.3003 - Aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.3003 Section..., Ute Mountain Ute, and All Other New Mexico Tribes § 147.3003 Aquifer exemptions. (a) Aquifer... described in appendix A are hereby exempted. The exempted aquifers are defined by a one-quarter mile...

  13. 40 CFR 147.302 - Aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.302 Section... Aquifer exemptions. (a) This section identifies any aquifers of their portions exempted in accordance with... other aquifers or portions according to applicable procedures without codifying such exemptions in...

  14. 40 CFR 147.1652 - Aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.1652 Section... Aquifer exemptions. (a) This section identifies any aquifer or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  15. 40 CFR 147.3003 - Aquifer exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.3003 Section..., Ute Mountain Ute, and All Other New Mexico Tribes § 147.3003 Aquifer exemptions. (a) Aquifer... described in appendix A are hereby exempted. The exempted aquifers are defined by a one-quarter mile...

  16. 40 CFR 147.1652 - Aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.1652 Section... Aquifer exemptions. (a) This section identifies any aquifer or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  17. 40 CFR 147.302 - Aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.302 Section... Aquifer exemptions. (a) This section identifies any aquifers of their portions exempted in accordance with... other aquifers or portions according to applicable procedures without codifying such exemptions in...

  18. 40 CFR 147.2102 - Aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.2102 Section....2102 Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in... future exempt other aquifers or their portions, according to applicable procedures, without...

  19. 40 CFR 147.102 - Aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.102 Section... Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  20. 40 CFR 147.1652 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1652 Section... Aquifer exemptions. (a) This section identifies any aquifer or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  1. 40 CFR 147.2102 - Aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.2102 Section....2102 Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in... future exempt other aquifers or their portions, according to applicable procedures, without...

  2. 40 CFR 147.1652 - Aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.1652 Section... Aquifer exemptions. (a) This section identifies any aquifer or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  3. 40 CFR 147.2102 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.2102 Section....2102 Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in... future exempt other aquifers or their portions, according to applicable procedures, without...

  4. 40 CFR 147.2554 - Aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.2554 Section... Aquifer exemptions. In accordance with §§ 144.7(b) and 146.4 of this chapter, those portions of aquifers... injection activity. This exemption applies only to the aquifers tabulated below, and includes those...

  5. 40 CFR 147.102 - Aquifer exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.102 Section... Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  6. 40 CFR 147.102 - Aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.102 Section... Aquifer exemptions. (a) This section identifies any aquifers or their portions exempted in accordance with... other aquifers or portions, according to applicable procedures, without codifying such exemptions...

  7. Republic of Colombia. Country Profile.

    PubMed

    Canak, W L

    1985-03-01

    This discussion of Colombia covers population growth, age distribution, regions and cities, households and families, housing and construction, ethnicity and religion, labor force and income, education, communications and transportation, and sources of information. Colombia's 1985 population is estimated at 28.7 million, making it the largest country in South America after Brazil. Colombia's growth in the last 5 years has averaged 2% annually, compared with an average of 2.3% a year for Latin America as a region. Colombia's moderate growth has been accompanied by shifts in population distribution and composition. In particular a massive internal migration has increased the urban population from roughly 1/3 in th 1950s to 2/3 at this time. Improved housing, education, and access to public health facilities have accompanied this rural to urban migration. At this time Colombia is holding its own economically and anticipates economic growth based on recovery in the US and Europe as well as on its own coal exports. Colombia's fertility rate, at 3.9 children/women in 1980-81, is the lowest in tropical South America but higher than the total fertility rate in the more temperate South American countries. Compared with other South American nations, Colombia's crude birthrate of 29-31 births/1000 population is low. Reflecting the impact of urban migration and the widescale effectiveness of family planning programs initiated in the 1960s and 1970s, median age has increased from 17 years in 1970 to almost 21 years in 1985. About 37% of the population is aged 14 or under at this time. The population aged 65 and older is only 3.8% and by 2000 will constitute only 4.5% of the population. From 1951-82 the urban population grew at 4.4% annually, exceeding the national average of 2.6% and the rural growth rate of less than 1%. Since 1982 the urban growth rate has been about 3% annually. In 1964 the average completed family size was 6.8 children. By 1980 it was 3.9 children. A steady

  8. SOLE SOURCE AQUIFER BOUNDARY DATA

    EPA Science Inventory

    There are 7 polygons representing 6 individual sole source aquifer boundaries and one streamflow source area in California, Arizona, and Nevada. Various efforts were combined to create the final product, which represents the Federal Register boundary description. Sole source aqu...

  9. Aquifer thermal energy storage program

    NASA Technical Reports Server (NTRS)

    Fox, K.

    1980-01-01

    The purpose of the Aquifer Thermal Energy Storage Demonstration Program is to stimulate the interest of industry by demonstrating the feasibility of using a geological formation for seasonal thermal energy storage, thereby, reducing crude oil consumption, minimizing thermal pollution, and significantly reducing utility capital investments required to account for peak power requirements. This purpose will be served if several diverse projects can be operated which will demonstrate the technical, economic, environmental, and institutional feasibility of aquifer thermal energy storage systems.

  10. [Violence and health in Colombia].

    PubMed

    Franco Agudelo, S

    1997-02-01

    In Colombia, violence seems uncontrollable. Along with massacres and group killings of astonishing cruelty, there are also kidnappings and disappearances, abuse of children and the elderly, and rape of young adolescents. Every day, without respite, Columbians are witnesses or victims of street crimes as well as racial, sexual, and socioeconomic discrimination. Unwillingly, they become agents of aggression in public transport, at home, at school, and at work. Colombia has the highest rates of mortality from homicide in the world. Apart from the enormous institutional burden that violence imposes on the health services and forensic medicine, it now constitutes the principal public health problem in the country. To confront it, the health sector must develop policies and finance actions, develop innovative ways to train personnel, implement public education processes, and devote more effort and greater creativity to research, which up to now has provided some, but not enough, important answers. Violence, which is the substitution of force for any type of dialogue, must be considered within the context of life and health. This it not merely an attempt to rationalize violence, much less to substitute words or reflection for action, but rather an attempt to understand it in depth in order to search for alternatives. With that goal, this article analyzes the subject of violence in Colombia, principally from the perspective of its effect on the health of the citizens and its implications for the health sector. The author fully recognizes the subjectivity and limitations of the views he expresses herein. PMID:9273199

  11. Prevention of School Desertion in Colombia

    ERIC Educational Resources Information Center

    Walker, Sarah

    2004-01-01

    Colombia has been ravaged for over 40-years by escalating civil conflict and more than half of its population of 42 million live below the poverty line. As a result, many children and young people are excluded from school and drop out rates of those who gain places are high. It is in Bogota, the capital of Colombia, where many displaced families…

  12. ANALYTICAL ELEMENT MODELING OF COASTAL AQUIFERS

    EPA Science Inventory

    Four topics were studied concerning the modeling of groundwater flow in coastal aquifers with analytic elements: (1) practical experience was obtained by constructing a groundwater model of the shallow aquifers below the Delmarva Peninsula USA using the commercial program MVAEM; ...

  13. 40 CFR 147.1352 - Aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.1352 Section 147.1352 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions. Those portions of aquifers within one-quarter mile of existing Class II wells...

  14. 40 CFR 147.1352 - Aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.1352 Section 147.1352 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions. Those portions of aquifers within one-quarter mile of existing Class II wells...

  15. 40 CFR 147.1352 - Aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1352 Section 147.1352 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions. Those portions of aquifers within one-quarter mile of existing Class II wells...

  16. 40 CFR 147.1352 - Aquifer exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.1352 Section 147.1352 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions. Those portions of aquifers within one-quarter mile of existing Class II wells...

  17. 40 CFR 147.1352 - Aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.1352 Section 147.1352 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions. Those portions of aquifers within one-quarter mile of existing Class II wells...

  18. Road traffic injuries in Colombia.

    PubMed

    Rodríguez, Deysi Yasmin; Fernández, Francisco José; Acero Velásquez, Hugo

    2003-01-01

    Road traffic injuries are a leading public health problem in Colombia. Pedestrians are the most vulnerable road users, especially in the main urban centers of Bogotá, Medellin and Cali. Data analyzed in this report include official statistics from the National Police and the National Institute of Legal Medicine and Forensic Sciences for 1996-2000, and results of a study conducted at the National University of Colombia in 2000. Methods from the Highway Capacity Manual were used for determining physical and technical variables, and a Geographical Information System tool was used for the location and spatial analysis of the road traffic crashes. Pedestrians accounted for close to 32% of injuries and 40% of the deaths from road traffic crashes. The problem of road traffic crashes existed predominately in urban areas. In the main urban centers, pedestrians constituted nearly 68% of road traffic crash victims. The high level of risky road use behaviors demonstrated by pedestrians and drivers, and inadequate infrastructure for safe mobility of pedestrians in some sections of the road network were the main contributing factors. Major improvements were achieved in Bogotá following enhancements to the municipal transport system and other policies introduced since 1995. In conclusion, policies and programs for improving road safety, in particular pedestrian safety, and strengthening urban planning are top priority. PMID:12772483

  19. Hydrogeologic atlas of aquifers in Indiana

    USGS Publications Warehouse

    Fenelon, Joseph M.; Bobay, K.E.; Greeman, T.K.; Hoover, M.E.; Cohen, D.A.; Fowler, K.K.; Woodfield, M.C.; and Durbin, J. M.

    1994-01-01

    Aquifers in 12 water-management basins of Indiana are identified in a series of 104 hydrogeologic sections and 12 maps that show the thickness and configuration of aquifers. The vertical distribution of water-bearing units and a generalized potentiometric profile are shown along 3,500 miles of section lines that were constructed from drillers' logs of more than 4,200 wells. The horizontal scale of the sections is 1:125,000. Maps of aquifers showing the areal distribution of each aquifer type were drawn at a scale of 1:500,000. Unconsolidated aquifers are the most widely used aquifers in Indiana and include surficial, buried, and discontinuous layers of sand and gravel. Most of the surficial sand and gravel is in large outwash plains in northern Indiana and along the major rivers. Buried sand and gravel aquifers are interbedded with till deposits in much of the northern two-thirds of Indiana. Discontinuous sand and gravel deposits are present as isolated lenses, primarily in glaciated areas. The bedrock aquifers generally have lower yields than most of the sand and gravel aquifers; however, bedrock aquifers are areally widespread and are an important source of water. Bedrock aquifer types consist of carbonates; sandstones; complexly interbedded sandstones, siltstones, shales, limestones, and coals; and an upper weathered zone in low permeability rock. Carbonate aquifers underlie about one-half of Indiana and are the most productive of the bedrock aquifers. The other principal bedrock aquifer type, sandstone, underlies large areas in the southwestern one-fifth of Indiana. No aquifer is known to be present in the southeastern corner of Indiana.

  20. Characterization of leaky faults: Study of water flow in aquifer-fault-aquifer systems

    NASA Astrophysics Data System (ADS)

    Shan, Chao; Javandel, Iraj; Witherspoon, Paul A.

    Leaky faults provide important flow paths for fluids to move underground. It is often necessary to characterize such faults in engineering projects such as deep well injection of waste liquids, underground natural gas storage, and radioactive waste isolation. To provide this characterization, analytical solutions are presented for groundwater flow through saturated aquifer-fault-aquifer systems assuming that both the aquifers and the fault are homogeneous and that the fault has an insignificant effect on aquifer hydraulic properties. Three different conditions are considered: (1) drawdown in the unpumped aquifer is negligibly small; (2) drawdown in the unpumped aquifer is significant, and the two aquifers have the same diffusivity; and (3) drawdown in the unpumped aquifer is significant, and the two aquifers have different diffusivities. Methods are presented to determine the fault transmissivity from pumping test data.

  1. An Energy Overview of Colombia

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site--each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Colombia. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  2. The Tuscaloosa Aquifer system in Mississippi

    USGS Publications Warehouse

    Boswell, E.H.

    1978-01-01

    A three-sheet map report describes the Tuscaloosa aquifer system in Mississippi. The Tuscaloosa aquifer system, of Cretaceous age , is in the interconnected irregular sand and gravel beds in the Coker and Gordo Formations. The aquifer contains freshwater in an area of about 9,000 sq mi in northeastern Mississippi. Water produced from the aquifer by about 90 water systems and numerous industries in 1975 averaged about 47 Mgal/d. Regional water level declines have averaged less than two feet per year and the aquifer has a large potential for future development. The aquifer is used in some areas where the dissolved-solids concentration is more than 500 mg/L and where wells exceed 2,000 ft in depth. The most common problems in water supplies are excessive chloride and iron. (Woodard-USGS)

  3. An evaluation of aquifer intercommunication between the unconfined and Rattlesnake Ridge aquifers on the Hanford Site

    SciTech Connect

    Jensen, E.J.

    1987-10-01

    During 1986, Pacific Northwest Laboratory conducted a study of a portion of the Rattlesnake Ridge aquifer (confined aquifer) that lies beneath the B Pond - Gable Mountain Pond area of the Hanford Site. The purpose was to determine the extent of intercommunication between the unconfined aquifer and the uppermost regionally extensive confined aquifer, referred to as the Rattlesnake Ridge aquifer. Hydraulic head data and chemical data were collected from the ground water in the study area during December 1986. The hydraulic head data were used to determine the effects caused by water discharged to the ground from B Pond on both the water table of the unconfined aquifer and the potentiometric surface of the confined aquifer. The chemical data were collected to determine the extent of chemical constituents migrating from the unconfined aquifer to the confined aquifer. Analysis of chemical constituents in the Rattlesnake Ridge aquifer demonstrated that communication between the unconfined and confined aquifers had occurred. However, the levels of contaminants found in the Rattlesnake Ridge aquifer during this study were below the DOE Derived Concentration Guides.

  4. Forensic investigation of sex crimes in Colombia.

    PubMed

    Cabelus, Nancy B; Sheridan, Gary T

    2007-01-01

    Victimization by sexual assault has become not only a public health and safety issue but a way of life for many in Colombia. Poverty, gender inequality, and a lack of family and community support contribute to the cycle of sexual violence. Ineffective medico-legal systems have added to a rate of 93% for sex crimes that go without arrest or prosecution in Bogotá, the capital. Collaborative efforts are underway between the United States and Colombian governments to change the criminal justice system and strengthen forensic investigation of sex crimes in Colombia. PMID:18027530

  5. VULNERABILITY OF KARST AQUIFERS TO CHEMICAL CONTAMINATION

    EPA Science Inventory

    Ground water flow in karst aquifers is very different from flow in granular or fractured aquifers. arst ground water flow is often turbulent within discrete conduits that are convergent in the upper reaches and divergent in the lower, simulating discharge to one or more springs. ...

  6. Overview of the Ogallala Aquifer Program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation increased markedly on the Southern High Plains during the second half of the 20th century, drawing water primarily from the Ogallala Aquifer. During this time, irrigation sustained regional farm incomes and rural economies. Withdrawals from the aquifer, however, have exceeded recharge, re...

  7. The Sparta Aquifer: A Sustainable Water Resource?

    USGS Publications Warehouse

    McKee, Paul W.; Hays, Phillip D.

    2002-01-01

    Introduction The Sparta aquifer is an aquifer of regional importance within the Mississippi embayment aquifer system. It consists of varying amounts of unconsolidated sand, inter-stratified with silt and clay lenses within the Sparta Sand of the Claiborne Group. It extends from south Texas, north into Louisiana, Arkansas, and Tennessee, and eastward into Mississippi and Alabama (fig. 1). On both the west and east sides of the Mississippi embayment, the Sparta aquifer is exposed at the surface (outcrops) and is locally unconfined; it becomes confined as it dips toward the axis of the embayment, (generally corresponding with the Mississippi River) and southward toward the Gulf of Mexico where it is deeply buried in the subsurface (Hosman, 1968). Generalized ground-water flow in the Sparta aquifer is from the outcrop areas to the axis (center) of the embayment (fig. 2). In Arkansas, the Sparta aquifer outcrops parallel to the Fall Line at the western extreme of the Mississippi embayment (the Fall Line is a line dividing the mountainous highlands of Arkansas from the lowland area); and the formation dips from its outcrop area to the southeast. The Sparta aquifer supplies water for municipalities, industries such as paper production, and to a lesser degree, irrigation of agricultural crops (fig. 3). This report highlights hydrologic conditions of the aquifer in Arkansas County as an example of how water use is affecting water levels.

  8. Evaluation of health risks for contaminated aquifers.

    PubMed Central

    Piver, W T; Jacobs, T L; Medina, M A

    1997-01-01

    This review focuses on progress in the development of transport models for heterogeneous contaminated aquifers, the use of predicted contaminant concentrations in groundwater for risk assessment for heterogeneous human populations, and the evaluation of aquifer remediation technologies. Major limitations and areas for continuing research for all methods presented in this review are identified. Images Figure 2. PMID:9114282

  9. SIMULATION OF SURFACTANT-ENHANCED AQUIFER REMEDIATION

    EPA Science Inventory

    Surfactant-enhanced aquifer remediation (SEAR) is currently under active investigation as one of the most promising alternatives to conventional pump-and-treat remediation for aquifers contaminated by dense nonaqueous phase organic liquids. An existing three-dimensional finite-di...

  10. Geohydrology of the Cerro Prieto geothermal aquifer

    SciTech Connect

    Sanchez R, J.; de la Pena L, A.

    1981-01-01

    The most recent information on the Cerro Prieto geothermal aquifer is summarized, with special emphasis on the initial production zone where the wells completed in the Alpha aquifer are located. These wells produce steam for power plant units 1 and 2. Brief comments also are made on the Beta aquifer, which underlies the Alpha aquifer in the Cerro Prieto I area and which extends to the east to what is known as the Cerro Prieto II and Cerro Prieto III areas. The location of the area studied is shown. The Alpha and Beta aquifers differ in their mineralogy and cementing mineral composition, temperatures, and piezometric levels. The difference in piezometric levels indicates that there is no local communication between the two aquifers. This situation has been verified by a well interference test, using well E-1 as a producer in the Beta aquifer and well M-46 as the observation well in the Alpha aquifer. No interference between them was observed. Information on the geology, geohydrology, and geochemistry of Cerro Prieto is presented.

  11. ANALYTIC ELEMENT MODELING OF COASTAL AQUIFERS

    EPA Science Inventory

    Four topics were studied concerning the modeling of ground-water flow in coastal aquifers with analytic elements: (1) practical experience was obtained by constructing a ground-water model of the shallow aquifers below the Delmarva Peninsula USA using the commercial program MVAEM...

  12. Coupled aquifer-borehole simulation.

    PubMed

    Clemo, Tom

    2010-01-01

    A model coupling fluid hydraulics in a borehole with fluid flow in an aquifer is developed in this paper. Conservation of momentum is used to create a one-dimensional steady-state model of vertical flow in an open borehole combined with radially symmetric flow in an aquifer and with inflow to the well through the wellbore screen. Both laminar and turbulent wellbore conditions are treated. The influence of inflow through the wellbore screen on vertical flow in the wellbore is included, using a relation developed by Siwoń (1987). The influence of inflow reduces the predicted vertical variation in head up to 15% compared to a calculation of head losses due to fluid acceleration and the conventional Colebrook-White formulation of friction losses in a circular pipe. The wellbore flow model is embedded into the MODFLOW-2000 ground water flow code. The nonlinear conservation of momentum equations are iteratively linearized to calculate the conductance terms for vertical flow in the wellbore. The resulting simulations agree favorably with previously published results when the model is adjusted to meet the assumptions of the previous coupled models. PMID:19682095

  13. Epidemiology and control of malaria in Colombia

    PubMed Central

    Rodríguez, Julio Cesar Padilla; Uribe, Gilberto Álvarez; Araújo, Roberto Montoya; Narváez, Pablo Chaparro; Valencia, Sócrates Herrera

    2016-01-01

    Malaria is currently one of the most serious public health problems in Colombia with an endemic/epidemic transmission pattern that has maintained endemic levels and an average of 105,000 annual clinical cases being reported over the last five years. Plasmodium vivax accounts for approximately 70% of reported cases with the remainder attributed almost exclusively to Plasmodium falciparum. A limited number of severe and complicated cases have resulted in mortality, which is a downward trend that has been maintained over the last few years. More than 90% of the malaria cases in Colombia are confined to 70 municipalities (about 7% of the total municipalities of Colombia), with high predominance (85%) in rural areas. The purpose of this paper is to review the progress of malaria-eradication activities and control measures over the past century within the eco-epidemiologic context of malaria transmission together with official consolidated morbidity and mortality reports. This review may contribute to the formulation of new antimalarial strategies and policies intended to achieve malaria elimination/eradication in Colombia and in the region. PMID:21881765

  14. Rural-Urban Migration in Colombia.

    ERIC Educational Resources Information Center

    Schultz, T. Paul

    The rural-urban migration pattern in Colombia during the last 25 years has resulted in a population increase in urban areas from 30 to 52 percent of the total population. This study explores the causes of internal migration. Migration rates are estimated for various groups in the population to clarify who migrates and to where. A model of…

  15. Astroparticle physics at the Eastern Colombia region

    NASA Astrophysics Data System (ADS)

    Asorey, Hernán; Núñez, Luis A.

    2015-12-01

    We present the emerging panorama of Astroparticle Physics at the Eastern Colombia region, and describe several ongoing projects, most of them related to the Latin American Giant Observatory (LAGO) Project. This research work is carried out at the Grupo de Investigaciones en Relatividad y Gravitacin of Universidad Industrial de Santander.

  16. Colombia Exports Its "New School" Blueprint.

    ERIC Educational Resources Information Center

    Lopez, Asbel

    1999-01-01

    To compensate for disadvantages of traditional rural schools, Colombia's Escuela Nueva (New School) movement offers solutions such as self-instruction guides geared to aspects of daily life and flexible school schedules. Teacher training that encourages student and community involvement is a key element. Escuela Nueva successes have led to its…

  17. Fuelling a National Innovation System in Colombia

    ERIC Educational Resources Information Center

    Lucio-Arias, Diana

    2006-01-01

    This presentation of the innovation-driven environment in Colombia derives from important national efforts to gather and store pertinent information. Two large surveys have tested the "innovative behaviour" of Colombian manufacturing firms--the more recent of these was in 2005. Another information source is the Scienti platform, an online effort…

  18. Protistan communities in aquifers: a review.

    PubMed

    Novarino, G; Warren, A; Butler, H; Lambourne, G; Boxshall, A; Bateman, J; Kinner, N E; Harvey, R W; Mosse, R A; Teltsch, B

    1997-07-01

    Eukaryotic microorganisms (protists) are a very important component of microbial communities inhabiting groundwater aquifers. This is not unexpected when one considers that many protists feed heterotrophically, by means of either phagotrophy (bacterivory) or osmotrophy. Protistan numbers are usually low (< 10(2) per g dw of aquifer material) in pristine, uncontaminated aquifers but may increase by several orders of magnitude in aquifers subject to organic pollution. Small flagellates (typically 2-3(5) microns in size in situ) are by far the dominant protists in aquifers, although amoebae and occasionally ciliates may also be present in much lower numbers. Although a wealth of new taxonomic information is waiting to be brought to light, interest in the identity of aquifer protists is not exclusively academic. If verified, the following hypotheses may prove to be important towards our understanding of the functioning of microbial communities in aquifers: (1) Differences in swimming behavior between species of flagellates lead to feeding heterogeneity and niche differentiation, implying that bacterivorous flagellates graze on different subsets of the bacterial community, and therefore play different roles in controlling bacterial densities. (2) Bacterivorous flagellates grazing on bacteria capable of degrading organic compounds have an indirect effect on the overall rates of biodegradation. PMID:9299706

  19. Analysis of aquifer mineralization by paleodrainage channels

    USGS Publications Warehouse

    Rubin, H.; Buddemeier, R.W.

    2003-01-01

    Mineralization of groundwater resources is a problem in south-central Kansas, due to the penetration of saline water from Permian bedrock formations into the overlying alluvial aquifer. One of the mechanisms involved in the mineralization involves small bedrock features of high permeability located in places occupied by streams and rivers in past geological eras. These geological features are termed 'paleodrainage channels'. The permeability of the overlying aquifer can be significantly smaller than that of the channel fill material. The comparatively fast migration of saline water through these channels of high permeability is associated with the transfer of minerals into the overlying freshwater aquifer. This study applies a set of boundary layer approaches to quantify the process of mineral transfer from the channels into the aquifer. The methods used in the present study provide quick estimation and evaluation of the dilution of the channel flow, as well as mineral concentration profile changes in the mineralized zone created in the overlying aquifer. More generally, the method can also be useful for the analysis and evaluation of various types of groundwater contamination in heterogeneous aquifers. The application of the method is exemplified by a complete set of calculations characterizing the possible mineralization process at a specific channel in south central Kansas. Sensitivity analyses are performed and provide information about the importance of the various parameters that affect the mineralization process. Some possible scenarios for the aquifer mineralization phenomena are described and evaluated. It is shown that the channel mineralization may create either several stream tubes of the aquifer with high mineral concentration, or many stream tubes mineralized to a lesser extent. Characteristics of these two patterns of aquifer mineralization are quantified and discussed. ?? 2003 Published by Elsevier Science B.V.

  20. Recharge from rectangular areas to finite aquifers

    NASA Astrophysics Data System (ADS)

    Rao, N. H.; Sarma, P. B. S.

    1981-10-01

    A generalized analytical solution is derived for the growth of groundwater mound in finite aquifers bounded by open water bodies, in response to recharge from rectangular areas. Finite Fourier transforms are used to solve the linearized differential equation of groundwater flow. Unlike earlier solutions, the method presented here does not require the use of tables for evaluation of complicated functions. The solution is evaluated by comparison with existing numerical and analytical results. In stream-aquifer systems similar to those described above, application of the proposed solution is more realistic than using solutions available for infinite aquifers.

  1. [Malnutrition and poverty in Colombia].

    PubMed

    Rico Velasco, J; Acciarri, G; Fajardo, L F

    1982-01-01

    A history of colonial exploitation and a development model that concentrates wealth and excludes a large proportion of the population from the development process are the principal determinants of income distribution in Colombia. This work analyzes the extent of malnutrition among the poorest 30% of the Colombian population. The National Plan for Feeding and Nutrition (PAN), an important component of the national development plan, strives to improve the nutritional status of the most vulnerable population groups living in rural areas and marginal urban neighborhoods, with particular emphasis on mothers and children. The program initially was focussed on 11 priority regions where 5 types of interventions were developed: primary health care, environmental sanitation, food production, food distribution, and nutrition education. Because of the good results initially obtained, PAN now covers the entire national territory. A 1977 survey stratified by socioeconomic levels indicated that among the poorest 30% of the population, 67% of the children examined had low weight for age caused by a combination of chronic and acute malnutrition. 12% were considered to have severe and 23% moderate malnutrition. 8% had severe and 17% had moderate problems of height for age. 26% had deficient weight for height. Comparison of the data to normal values published by the World Health Organization clearly demonstrates the pattern of overall malnutrition indicated by weight for age figures. It can be concluded at 33% of children in the poorest 30% of the population are normal, 31% have mild malnutrition, 23% moderate malnutrition, and 12% severe malnutrition. Data on height for age indicated that 43% were normal, 32% had mild chronic malnutrition, 17% had moderate chronic malnutrition, and 8% had severe chronic malnutrition. The prevalence of acute malnutrition in the poor population measured by the ratio of weight to height was less than that of chronic or overall malnutrition. 21% were

  2. CSM: Profamilia's approach in Colombia.

    PubMed

    Samuel, S

    1982-03-01

    Colombia's PROFAMILIA has successfully operated a contraceptive social marketing (CSM) program since 1973. Beginning with 1 salesperson distributing primarily to Cajas de Subsideio, the CSM program is now distributed through 70-80% of the 6000 registered pharmacies in the country, as well as pharmacy counters of several supermakets in urban areas. During 1981, PROFAMILIA's 5 salespersons accountd for commerical sales of oral contraceptives (OCs) to 225,000 couples and sales of barrier methods to another 75,000. Program sales of contraceptives and other products generated approximately US $1.7 million in revenue for the same year. PROFAMILIA's marketing approach is unique in its product and promotinal characteristics. Supplies are obtained directly from local and foreign manufacturers and are resold without any repackaging. While it is generally believed that CSM programs expand the market for contraceptives, data analysis and analysis of PROFAMILIA's distribution system suggests that the PROFAMILIA CSM program has simply absorbed some of the previously existing commerical market. Total commerical market sales of oral contraceptives (OCs) have grown at an annual rate of 3-4% since 1975. During the same period, direct sales of Schering, Wyeth, and other competitors have declined. PROFAMILIA's community-based program operates mainly among urban and semi-rural lower income populations. It sells products through established retail outlets rather than through institutional or non-retail outlets. PROFAMILIA's community-based program in all respects but its use of a staff of 112 salaried "instructoras" is as much a marketing program as PROFAMILIA's sales through pharmacies. Taken together, the 2 program expanded the commerical makert by about 1/2 since 1975. The contraceptive social marketing or pharmacy sales program appears to excel at generation of revenue and delivery of products to higher income clients. The community-based program excels at delivery of information

  3. Aquifer descriptions from the U.S. Geological Survey Regional Aquifer-System Analysis Program, 1978-1993

    USGS Publications Warehouse

    Davidson, Claire B.; Doherty, Helen

    1994-01-01

    The Regional Aquifer-System Analysis Program of the U.S. Geological Survey began in 1978. The overall purpose of this program is to define the geologic, hydrologic, and geochemical framework of the Nation's most important aquifers and aquifer systems. This report summarizes the aquifer or aquifer system name, geographic area, rock units, equivalent names, lithology, thickness, hydrologic characteristics, water quality, water use, and references for 157 aquifers in 23 areas of the United States. A .zip file containing the aquifer data and data search programs (in compressed ASCII format) is included in the report.

  4. Digital data sets that describe aquifer characteristics of the Enid isolated terrace aquifer in northwestern Oklahoma

    USGS Publications Warehouse

    Becker, C.J.; Runkle, D.L.; Rea, Alan

    1997-01-01

    ARC/INFO export and nonproprietary format files The data sets in this report include digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Enid isolated terrace aquifer in northwestern Oklahoma. The Enid isolated terrace aquifer covers approximately 82 square miles and supplies water for irrigation, domestic, municipal, and industrial use for the City of Enid and western Garfield County. The Quaternary-age Enid isolated terrace aquifer is composed of terrace deposits that consist of discontinuous layers of clay, sandy clay, sand, and gravel. The aquifer is unconfined and is bounded by the underlying Permian-age Hennessey Group on the east and the Cedar Hills Sandstone Formation of the Permian-age El Reno Group on the west. The Cedar Hills Sandstone Formation fills a channel beneath the thickest section of the Enid isolated terrace aquifer in the midwestern part of the aquifer. All of the data sets were digitized and created from information and maps in a ground-water modeling thesis and report of the Enid isolated terrace aquifer. The maps digitized were published at a scale of 1:62,500. Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may produce similar results. Therefore, values of hydraulic conductivity and recharge used in the model and presented in this data set are not precise, but are within a reasonable range when compared to independently collected data.

  5. Solute changes during aquifer storage recovery testing in a limestone/clastic aquifer

    USGS Publications Warehouse

    Mirecki, J.E.; Campbell, B.G.; Conlon, K.J.; Petkewich, M.D.

    1998-01-01

    Aquifer storage recovery (ASR) was tested in the Santee Limestone/Black Mingo Aquifer near Charleston, South Carolina, to assess the feasibility for subsurface storage of treated drinking water. Water quality data obtained during two representative ASR tests were interpreted to show three things: (1) recovery efficiency of ASR in this geological setting; (2) possible changes in physical characteristics of the aquifer during ASR testing; and (3) water quality changes and potability of recovered water during short (one- and six-day) storage durations in the predominantly carbonate aquifer. Recovery efficiency for both ASR tests reported here was 54%. Successive ASR tests increased aquifer permeability of the Santee Limestone/Black Mingo Aquifer. It is likely that aquifer permeability increased during short storage periods due to dissolution of carbonate minerals and amorphous silica in aquifer material by treated drinking water. Dissolution resulted in an estimated 0.3% increase in pore volume of the permeable zones. Ground water composition generally evolved from a sodium-calcium bicarbonate water to a sodium chloride water during storage and recovery. After short duration, stored water can exceed the U.S. Environmental Protection Agency maximum contaminant level (MCL) for chloride (250 mg/L). However, sulfate, fluoride, and trihalomethane concentrations remained below MCLs during storage and recovery.Aquifer storage recovery (ASR) was tested in the Santee Limestone/Black Mingo Aquifer near Charleston, South Carolina, to assess the feasibility for subsurface storage of treated drinking water. Water quality data obtained during two representative ASR tests were interpreted to show three things: (1) recovery efficiency of ASR in this geological setting; (2) possible changes in physical characteristics of the aquifer during ASR testing; and (3) water quality changes and potability of recovered water during short (one- and six-day) storage durations in the predominantly

  6. Vulnerability of unconfined aquifers to virus contamination.

    PubMed

    Schijven, J F; Hassanizadeh, S Majid; de Roda Husman, Ana Maria

    2010-02-01

    An empirical formula was developed for determining the vulnerability of unconfined sandy aquifers to virus contamination, expressed as a dimensionless setback distance r(s)(*). The formula can be used to calculate the setback distance required for the protection of drinking water production wells against virus contamination. This empirical formula takes into account the intrinsic properties of the virus and the unconfined sandy aquifer. Virus removal is described by a rate coefficient that accounts for virus inactivation and attachment to sand grains. The formula also includes pumping rate, saturated thickness of the aquifer, depth of the screen of the pumping well, and anisotropy of the aquifer. This means that it accounts also for dilution effects as well as horizontal and vertical virus transport. Because the empirical model includes virus source concentration it can be used as an integral part of a quantitative viral risk assessment. PMID:20110099

  7. PRINCIPAL AQUIFERS, CURRENT POTENTIOMETRIC SURFACE MAPS, NC

    EPA Science Inventory

    Web page from North Carolina Department of Environment and Natural Resources (NC-DENR) to maps of potentiometric surfaces by aquifer in NC.
    http://www.dwr.ehnr.state.nc.us/hms/gwbranch/charact.htm

  8. OXIDATION-REDUCTION CAPACITIES OF AQUIFER SOLIDS

    EPA Science Inventory

    Measurements of the oxidation (i.e., of aqueous Cr2+) and reduction (i.e., of aqueous Cr2O72- and H202) capacities of aquifer solids and groundwater have been made on samples from a sand-and-gravel aquifer. The gro...

  9. Estimated Withdrawals from Stream-Valley Aquifers and Refined Estimated Withdrawals from Selected Aquifers in the United States, 2000

    USGS Publications Warehouse

    Sargent, B. Pierre; Maupin, Molly A.; Hinkle, Stephen R.

    2008-01-01

    The U.S. Geological Survey National Water Use Information Program compiles estimates of fresh ground-water withdrawals in the United States on a 5-year interval. In the year-2000 compilation, withdrawals were reported from principal aquifers and aquifer systems including two general aquifers - Alluvial and Other aquifers. Withdrawals from a widespread aquifer group - stream-valley aquifers - were not specifically identified in the year-2000 compilation, but they are important sources of ground water. Stream-valley aquifers are alluvial aquifers located in the valley of major streams and rivers. Stream-valley aquifers are long but narrow aquifers that are in direct hydraulic connection with associated streams and limited in extent compared to most principal aquifers. Based in large part on information published in U.S. Geological Survey reports, preliminary analysis of withdrawal data and hydrogeologic and surface-water information indicated areas in the United States where possible stream-valley aquifers were located. Further assessment focused on 24 states and the Commonwealth of Puerto Rico. Withdrawals reported from Alluvial aquifers in 16 states and withdrawals reported from Other aquifers in 6 states and the Commonwealth of Puerto Rico were investigated. Two additional States - Arkansas and New Jersey - were investigated because withdrawals reported from other principal aquifers in these two States may be from stream-valley aquifers. Withdrawals from stream-valley aquifers were identified in 20 States and were about 1,560 Mgal/d (million gallons per day), a rate comparable to withdrawals from the 10 most productive principal aquifers in the United States. Of the 1,560 Mgal/d of withdrawals attributed to stream-valley aquifers, 1,240 Mgal/d were disaggregated from Alluvial aquifers, 150 Mgal/d from glacial sand and gravel aquifers, 116 Mgal/d from Other aquifers, 28.1 Mgal/d from Pennsylvanian aquifers, and 24.9 Mgal/d from the Mississippi River Valley alluvial

  10. Aquifer test results, Green Swamp area, Florida

    USGS Publications Warehouse

    Tibbals, C.H.; Grubb, Hayes F.

    1982-01-01

    An aquifer test conducted in the Green Swamp area December 15-16 , 1975 was designed to stress the uppermost part of the Floridan aquifer so that the leakage characteristics of the overlying confining bed could be determined. A well tapping the upper part of the Floridan aquifer was pumped at a rate of about 1,040 gallons per minute for 35 hours; drawdown was measured in the Floridan aquifer and in two horizons in the confining bed. Analysis of the data indicates that the transmissivity of the uppper 160 feet of the Floridan is 13,000 square feet per day, the storage coefficient is about 0.0002.5, and the overlying confining bed leakance coefficient is about 0.02 to 0.025 per day. The vertical hydraulic diffusivity of the confining bed ranged from 610 square feet per day to 16,000 square feet per day. Results of the test indicate that, in the area of the test site, a Floridan aquifer well field would induce additional recharge to the Floridan. As a result of that increased recharge , water levels in the surficial aquifer would tend to stand lower, runoff from the area would tend to be less, and, perhaps, evapotranspiration would be less than normal.(USGS)

  11. Digital data sets that describe aquifer characteristics of the Elk City Aquifer in western Oklahoma

    USGS Publications Warehouse

    Becker, C.J.; Runkle, D.L.; Rea, Alan

    1997-01-01

    ARC/INFO export and nonproprietary format files This diskette contains digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Elk City aquifer in western Oklahoma. The aquifer covers an area of approximately 193,000 acres and supplies ground water for irrigation, domestic, and industrial purposes in Beckham, Custer, Roger Mills, and Washita Counties along the divide between the Washita and Red River basins. The Elk City aquifer consists of the Elk City Sandstone and overlying terrace deposits, made up of clay, silt, sand and gravel, and dune sands in the eastern part and sand and gravel of the Ogallala Formation (or High Plains aquifer) in the western part of the aquifer. The Elk City aquifer is unconfined and composed of very friable sandstone, lightly cemented with clay, calcite, gypsum, or iron oxide. Most of the grains are fine-sized quartz but the grain size ranges from clay to cobble in the aquifer. The Doxey Shale underlies the Elk City aquifer and acts as a confining unit, restricting the downward movement of ground water. All of the data sets were digitized and created from information and maps in a ground-water modeling thesis and report of the Elk City aquifer. The maps digitized were published at a scale of 1:63,360. Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may produce similar results. Therefore, values of hydraulic conductivity and recharge used in the model and presented in this data set are not precise, but are within a reasonable range when compared to independently collected data.

  12. A General Solution for Groundwater Flow in Estuarine Leaky Aquifer System with Considering Aquifer Anisotropy

    NASA Astrophysics Data System (ADS)

    Chen, Po-Chia; Chuang, Mo-Hsiung; Tan, Yih-Chi

    2014-05-01

    In recent years the urban and industrial developments near the coastal area are rapid and therefore the associated population grows dramatically. More and more water demand for human activities, agriculture irrigation, and aquaculture relies on heavy pumping in coastal area. The decline of groundwater table may result in the problems of seawater intrusion and/or land subsidence. Since the 1950s, numerous studies focused on the effect of tidal fluctuation on the groundwater flow in the coastal area. Many studies concentrated on the developments of one-dimensional (1D) and two-dimensional (2D) analytical solutions describing the tide-induced head fluctuations. For example, Jacob (1950) derived an analytical solution of 1D groundwater flow in a confined aquifer with a boundary condition subject to sinusoidal oscillation. Jiao and Tang (1999) derived a 1D analytical solution of a leaky confined aquifer by considered a constant groundwater head in the overlying unconfined aquifer. Jeng et al. (2002) studied the tidal propagation in a coupled unconfined and confined costal aquifer system. Sun (1997) presented a 2D solution for groundwater response to tidal loading in an estuary. Tang and Jiao (2001) derived a 2D analytical solution in a leaky confined aquifer system near open tidal water. This study aims at developing a general analytical solution describing the head fluctuations in a 2D estuarine aquifer system consisted of an unconfined aquifer, a confined aquifer, and an aquitard between them. Both the confined and unconfined aquifers are considered to be anisotropic. The predicted head fluctuations from this solution will compare with the simulation results from the MODFLOW program. In addition, the solutions mentioned above will be shown to be special cases of the present solution. Some hypothetical cases regarding the head fluctuation in costal aquifers will be made to investigate the dynamic effects of water table fluctuation, hydrogeological conditions, and

  13. Sirenomelia: two cases in Cali, Colombia.

    PubMed

    Saldarriaga, Wilmar; Salcedo-Arellano, Maria Jimena; Ramirez-Cheyne, Julian

    2015-01-01

    We report two cases of sirenomelia, a rare congenital defect with a prevalence rate of 1:100 000 births; both cases were observed in Cali, Colombia. Both pregnant women were referred from Buenaventura, Colombia. The expecting mothers shared multiple adverse sociodemographic factors. Their homes were located in a city where the entire population is of low socioeconomic status living under conditions of extreme poverty. They were uneducated, with nutritional deficiencies and no access to drinking water most of the time. Both were exposed to water and fish from a nearby river contaminated with leachate from a poorly managed landfill. A similar relation was previously reported in Cali in 2005 between environmental factors and sirenomelia. We suggest that there is a common aetiological factor of environmental origin between these two sirenomelia cases and propose that exposure to derivatives from landfills should be included among the factors for this rare defect of multifactorial aetiological origin. PMID:25636631

  14. Distributional Scaling in Heterogeneous Aquifers

    NASA Astrophysics Data System (ADS)

    Polsinelli, J. F.

    2015-12-01

    An investigation is undertaken into the fractal scaling properties of the piezometric head in a heterogeneous unconfined aquifer. The governing equations for the unconfined flow are derived from conservation of mass and the Darcy law. The Dupuit approximation will be used to model the dynamics. The spatially varying nature of the tendency to conduct flow (e.g. the hydraulic conductivity) is represented as a stochastic process. Experimental studies in the literature have indicated that the conductivity belongs to a class of non-stationary stochastic fields, called H-ss fields. The uncertainty in the soil parameters is imparted onto the flow variables; in groundwater investigations the potentiometric head will be a random function. The structure of the head field will be analyzed with an emphasis on the scaling properties. The scaling scheme for the modeling equations and the simulation procedure for the saturated hydraulic conductivity process will be explained, then the method will be validated through numerical experimentation using the USGS Modflow-2005 software. The results of the numerical simulations demonstrate that the head will exhibit multi-fractal scaling if the hydraulic conductivity exhibits multi-fractal scaling and the differential equations for the groundwater equation satisfy a particular set of scale invariance conditions.

  15. Mineral resources of Colombia (other than petroleum)

    USGS Publications Warehouse

    Singewald, Quentin Dreyer

    1950-01-01

    The following report summarizes data acquired during 1942-45, in Colombia, by geologists and engineers of the Foreign Economic Administration, with whom the United States Geological Survey cooperated. Twenty-nine mineral commodities are considered, but the data for five of them are scant because they were of no interest to FEA personnel. Petroleum is not considered. Preliminary to a review of individual mineral commodities, resumes are given of the general geography and geology of Colombia and of the country's mining laws. The principal mineral commodities, besides petroleum, produced in Colombia are (1) emeralds, gold, platinum, and silver, mainly for export, and (2) barite, cement, clay, coal, gypsum, salt, sand and gravel, silica, and stone, mainly for the domestic market. A large number of other mineral commodities are known in "raw" prospects, some of which may eventually become productive. Their distribution and apparent potentialities, as of 1945, are given. Factors unfavorable to mining are the ruggedness of the terrain, the scarcity of outcrops, and the very high transportation costs.

  16. Aquifer Storage Recovery (ASR) of chlorinated municipal drinking water in a confined aquifer

    USGS Publications Warehouse

    Izbicki, John A.; Petersen, Christen E.; Glotzbach, Kenneth J.; Metzger, Loren F.; Christensen, Allen H.; Smith, Gregory A.; O'Leary, David R.; Fram, Miranda S.; Joseph, Trevor; Shannon, Heather

    2010-01-01

    About 1.02 x 106 m3 of chlorinated municipal drinking water was injected into a confined aquifer, 94-137 m below Roseville, California, between December 2005 and April 2006. The water was stored in the aquifer for 438 days, and 2.64 x 106 m3 of water were extracted between July 2007 and February 2008. On the basis of Cl data, 35% of the injected water was recovered and 65% of the injected water and associated disinfection by-products (DBPs) remained in the aquifer at the end of extraction. About 46.3 kg of total trihalomethanes (TTHM) entered the aquifer with the injected water and 37.6 kg of TTHM were extracted. As much as 44 kg of TTHMs remained in the aquifer at the end of extraction because of incomplete recovery of injected water and formation of THMs within the aquifer by reactions with freechlorine in the injected water. Well-bore velocity log data collected from the Aquifer Storage Recovery (ASR) well show as much as 60% of the injected water entered the aquifer through a 9 m thick, high-permeability layer within the confined aquifer near the top of the screened interval. Model simulations of ground-water flow near the ASR well indicate that (1) aquifer heterogeneity allowed injected water to move rapidly through the aquifer to nearby monitoring wells, (2) aquifer heterogeneity caused injected water to move further than expected assuming uniform aquifer properties, and (3) physical clogging of high-permeability layers is the probable cause for the observed change in the distribution of borehole flow. Aquifer heterogeneity also enhanced mixing of native anoxic ground water with oxic injected water, promoting removal of THMs primarily through sorption. A 3 to 4-fold reduction in TTHM concentrations was observed in the furthest monitoring well 427 m downgradient from the ASR well, and similar magnitude reductions were observed in depth-dependent water samples collected from the upper part of the screened interval in the ASR well near the end of the extraction

  17. Review of Aquifer Storage and Recovery Performance in the Upper Floridan Aquifer in Southern Florida

    USGS Publications Warehouse

    Reese, Ronald S.

    2006-01-01

    Introduction: Interest and activity in aquifer storage and recovery (ASR) in southern Florida has increased greatly during the past 10 to 15 years. ASR wells have been drilled to the carbonate Floridan aquifer system at 30 sites in southern Florida, mostly by local municipalities or counties located in coastal areas. The primary storage zone at these sites is contained within the brackish to saline Upper Floridan aquifer of the Floridan aquifer system. The strategy for use of ASR in southern Florida is to store excess freshwater available during the wet season in an aquifer and recover it during the dry season when needed for supplemental water supply. Each ASR cycle is defined by three periods: recharge, storage, and recovery. This fact sheet summarizes some of the findings of a second phase retrospective assessment of existing ASR facilities and sites.

  18. Preliminary delineation and description of the regional aquifers of Tennessee : the Highland Rim aquifer system

    USGS Publications Warehouse

    Brahana, J.V.; Bradley, M.W.

    1986-01-01

    The Highland Rim aquifer system in Tennessee is primarily composed of Mississippian carbonates and occurs west of the Valley and Ridge Province. It crops out in the Highland Rim and the Sequatchie Valley. It has been removed by erosion from the Central Basin. Groundwater in the Highland Rim aquifer system occurs primarily in secondary openings including solution openings, joints, and faults. The Chattanooga Shale is the lower confining layer for the Highland Rim aquifer system. Under the Cumberland plateau, this aquifer system is separated from the overlying Pennsylvanian formations by the Pennington Shale. The Highland Rim aquifer system is an important source of drinking water. It supplies most of the rural, domestic, and many public supplies of drinking water in the Highland Rim. Where there is a dynamic flow system, dissolved solids concentrations are less than 500 mg/L. However, isolated cells may exist where the groundwater has dissolved solids concentrations of more than 1 ,000 mg/L. (USGS)

  19. Basement Aquifers : How Useful Are Gravity Data ?

    NASA Astrophysics Data System (ADS)

    Genthon, P.; Mouhouyouddine, A. H.; Hinderer, J.; Hector, B.; Yameogo, S.

    2014-12-01

    Gravity data with a few microgal precision were proved to be able to constrain the specific yield of various kinds of aquifer in West Africa from annual fluctuations of both the gravimetric and piezometric signals (Pfeffer et al., Geophys. J. Int., 2011; Hector et al., Geophys. J. Int., 2013). However some recent papers reported a disappointing potential of gravity measurements during a pumping experiment in a sandy aquifer (Blainey et al., WRR, 2007; Herckenrath et al., WRR, 2012) and their poor ability in constraining the transmissity and specific yield of the aquifer, which are the parameters to which pumping tests give access. Fresh basement rocks present generally a null porosity and the structure of basement aquifers is given by the weathering profile. In tropical climate, this profile consists of a few tens meter thick saprolite layer, with noticeable porosity but low permeability overlying the weathering front. This weathering front includes in many instances a fractured medium and presents a high permeability with variable porosity. It is hardly sampled in coring experiments. We present some numerical simulation results on the ability of gravity to constrain the transmissivity of this medium. Due to poroelasticity of clay minerals in the saprolite, soil subsidence is expected to occur during pumping with a significant gravity effect. Gravity measurements have therefore to be completed with leveling data at a millimetric precision. We present first the results of numerical modeling of the gravity and subsidence for a theoretical horizontally stratified basement aquifer, and show that gravity and leveling are able to provide independently the poroelasticity coefficient and a single transmissivity coefficient for the bottom of the aquifer, if the properties of the upper saprolites are known. We will discuss then the general case, where the aquifer presents a vertical fracture where the weathering profile thickens.

  20. Stochastic analysis of virus transport in aquifers

    USGS Publications Warehouse

    Campbell, Rehmann L.L.; Welty, C.; Harvey, R.W.

    1999-01-01

    A large-scale model of virus transport in aquifers is derived using spectral perturbation analysis. The effects of spatial variability in aquifer hydraulic conductivity and virus transport (attachment, detachment, and inactivation) parameters on large-scale virus transport are evaluated. A stochastic mean model of virus transport is developed by linking a simple system of local-scale free-virus transport and attached-virus conservation equations from the current literature with a random-field representation of aquifer and virus transport properties. The resultant mean equations for free and attached viruses are found to differ considerably from the local-scale equations on which they are based and include effects such as a free-virus effective velocity that is a function of aquifer heterogeneity as well as virus transport parameters. Stochastic mean free-virus breakthrough curves are compared with local model output in order to observe the effects of spatial variability on mean one-dimensional virus transport in three-dimensionally heterogeneous porous media. Significant findings from this theoretical analysis include the following: (1) Stochastic model breakthrough occurs earlier than local model breakthrough, and this effect is most pronounced for the least conductive aquifers studied. (2) A high degree of aquifer heterogeneity can lead to virus breakthrough actually preceding that of a conservative tracer. (3) As the mean hydraulic conductivity is increased, the mean model shows less sensitivity to the variance of the natural-logarithm hydraulic conductivity and mean virus diameter. (4) Incorporation of a heterogeneous colloid filtration term results in higher predicted concentrations than a simple first-order adsorption term for a given mean attachment rate. (5) Incorporation of aquifer heterogeneity leads to a greater range of virus diameters for which significant breakthrough occurs. (6) The mean model is more sensitive to the inactivation rate of viruses

  1. Multidepth pumping tests in deep aquifers.

    PubMed

    Alam, N; Olsthoorn, T N

    2014-09-01

    Multidepth pumping tests (MDPTs), in which different sections of a screen are pumped in sequence, are not being used by hydrogeologists, despite the capability of such tests to resolve uncertainties in the estimation of aquifer characteristics. MDPTs can be used to discern the effects of partial penetration and vertical anisotropy. This article demonstrates the use of MDPTs for a deep and vertically anisotropic aquifer, based on a real and unique series of pumping tests conducted in the Indus Basin. Traditional single-layer methods, which incorporate partial penetration and vertical scaling, were employed to evaluate these tests. However, the drawdowns of the 19 piezometers at different depths for which times series data were available could not be matched, presumably because of the layered structure of the aquifer. Numerical (MODFLOW) and multilayer analytical (Hemker and Maas 1987; Hemker 1999) approaches were used to assess the benefits of using MDPTs in the analysis of deep layered and anisotropic aquifers. The multilayer analytical solution results are consistent with the measured and numerically computed drawdowns. The original step-drawdown data were used to verify the model independently. The results of statistical analyses indicate that the parameters for a three-layer system are uniquely estimated. A sensitivity analysis showed that aquifer depths greater than 900 m do not affect the drawdown. The multilayer analytical solution was implemented in MATLAB and can be found in the online version of this article. This multilayer analytical approach was implemented in MLU by Hemker and Randall (2013) for up to 40 layers. The results of this study will be useful in groundwater management, exploration, and optimal well depth estimation for the Indus Basin aquifer and other vertically heterogeneous aquifers. PMID:24428328

  2. The Politics of Rural School Reform: Escuela Nueva in Colombia.

    ERIC Educational Resources Information Center

    McEwan, Patrick J.; Benveniste, Luis

    2001-01-01

    Traces evolution of rural-school education plan in Colombia (Escuela Nueva), focusing on importance of Colombia's changing political and social climate in policy development. Identifies three phases of reform development and implementation: grassroots, formalized, and decoupled. Uses Escuela Nueva to demonstrate importance of recognizing dynamic,…

  3. Aquifer-characteristics data for West Virginia

    USGS Publications Warehouse

    Kozar, Mark D.; Mathes, Melvin V.

    2001-01-01

    Specific-capacity, storage-coefficient, and specific-yield data for wells in West Virginia were compiled to provide a data set from which transmissivity could be estimated. This data can be used for analytical and mathematical groundwater flow modeling. Analysis of available storage-coefficient and (or) specific-yield data indicates the Ohio River alluvial aquifer has a median specific yield of 0.20, which is characteristic of an unconfined aquifer. The Kanawha River alluvial aquifer has a median specific yield of 0.003, which is characteristic of a semi-confined aquifer. The median storage coefficient of fractured-bedrock aquifers is only 0.007, which is characteristic of confined aquifers. The highest median transmissivity of a specific aquifer in West Virginia occurs in Ohio River alluvium (4,800 ft2/d); the second highest occurs in Kanawha River alluvium (1,600 ft2/d). The lowest median transmissivity (23 ft2/d) is for the McKenzie-Rose Hill-Tuscarora aquifer. Rocks of Cambrian age within the Waynesboro-Tomstown-Harpers-Weverton-Loudon aquifer had a low median transmissivity of only 67 ft2/d. Other aquifers with low transmissivities include the Hampshire Formation, Brallier-Harrell Formations, Mahantango Formations, Oriskany Sandstone, and the Conococheague Formation with median transmissivities of 74, 72, 92, 82, and 92 ft2/d, respectively. All other aquifers within the State had intermediate values of transmissivity (130-920 ft2/d). The highest median transmissivities among bedrock aquifers were those for aquifers within the Pennsylvanian age Pocahontas Formation (1,200 ft2/d) and Pottsville Group (1,300 ft2/d), and the Mississippian age Mauch Chunk Group (1,300 ft2/d). These rocks crop out primarily in the southern part of the State and to a lesser extent within the Valley and Ridge Physiographic Province in West Virginia's Eastern Panhandle. The highest mean annual ground-water recharge rates within West Virginia (24.6 in.) occur within a band that extends

  4. Deconstructing nitrate isotope dynamics in aquifers

    NASA Astrophysics Data System (ADS)

    Granger, J.

    2012-12-01

    The natural abundance N and O stable isotope ratios of nitrate provide an invaluable tool to differentiate N sources to the environment, track their dispersal, and monitor their attenuation by biological transformations. The interpretation of patterns in isotope abundances relies on knowledge of the isotope ratios of the source end-members, as well as on constraints on the isotope discrimination imposed on nitrate by respective biological processes. Emergent observations from mono-culture experiments of denitrifying bacteria reveal nitrate fractionation trends that appear at odds with trends ascribed to denitrification in soils and aquifers. This discrepancy raises the possibility that additional biological N transformations may be acting in tandem with denitrification. Here, the N and O isotope enrichments associated with nitrate removal by denitrification in aquifers are posited to bear evidence of coincident biological nitrate production - from nitrification and/or from anammox. Simulations are presented from a simple time-dependent one-box model of a groundwater mass ageing that is subject to net nitrate loss by denitrification with coincident nitrate production by nitrification or anammox. Within boundary conditions characteristic of freshwater aquifers, the apparent slope of the parallel enrichments in nitrate N and O isotopes associated with net N loss to denitrification can vary in proportion to the nitrate added simultaneous by oxidative processes. Pertinent observations from nitrate plumes in suboxic to anoxic aquifers are examined to validate this premise. In this perspective, nitrate isotope distributions suggest that we may be missing important N fluxes inherent to most aquifers.

  5. Calcite cements in the modern Floridan aquifer

    SciTech Connect

    Hammes, U.; Budd, D.A. )

    1991-03-01

    Calcite cements in the Ocala (Eocene) and Suwannee (Oligocene) formations, southwestern Floridan aquifer have been studied to determine updip to downdip variations in cement chemistries and cathodoluminescence within a modern regional confined aquifer. Interparticle, intraparticle, and fracture-fill cements comprise 5-15% of the limestones. Five different calcite cement morphologies are distinguishable and occur throughout the aquifer: (1) circumgranular microspar, (2) fine- to medium-crystalline rhombs, (3) medium-crystalline syntaxial overgrowths on echinoderms, (4) fine-crystalline pore-filling mosaics, and (5) micrite. Type 5 occurs only below former exposure surfaces. Volumetrically, type 3 is the most important and type 4 is the least. Cathodoluminescence observations reveal only nonluminescent cements updip and an increase in luminescent zones and luminescent intensity downdip. Updip nonluminescent cements have very low Fe and Mn concentrations, but high Mg and Sr concentrations. These relations are interpreted to reflect oxidizing conditions and high rock/water interaction. Fe and Mn concentrations increase and Sr and Mg contents decrease downdip. These trends are interpreted to reflect reducing conditions, cross-formational flow, and slower rock/water interaction. Downdip cathodoluminescence zonations consist of a broad nonluminescent zone, followed by a thin bright orange zone, and then a dull luminescence zone. These geochemical and luminescent patterns along a regional flow line in the confined Floridan aquifer have many similarities to those observed in calcite cements described from ancient aquifers.

  6. Digital data sets that describe aquifer characteristics of the Central Oklahoma Aquifer in central Oklahoma

    USGS Publications Warehouse

    Runkle, D.L.; Christenson, S.C.; Rea, Alan

    1997-01-01

    ARC/INFO export files The data sets in this report include digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Central Oklahoma aquifer in central Oklahoma. This area encompasses all or part of Cleveland, Lincoln, Logan, Oklahoma, Payne, and Pottawatomie Counties. The Central Oklahoma aquifer includes the alluvial and terrace deposits along major streams, the Garber Sandstone and Wellington Formations, and the Chase, Council Grove, and Admire Groups. The Quaternary-age alluvial and terrace deposits consist of unconsolidated clay, silt, sand, and gravel. The Permian-age Garber Sandstone and Wellington Formations consist of sandstone with interbedded siltstone and mudstone. The Permian-age Chase, Council Grove, and Admire Groups consist of sandstone, shale, and thin limestone. The Central Oklahoma aquifer underlies about 3,000 square miles of central Oklahoma where the aquifer is used extensively for municipal, industrial, commercial, and domestic water supplies. Most of the usable ground water within the aquifer is from the Garber Sandstone and Wellington Formations. Substantial quantities of usable ground water also are present in the Chase, Council Grove, and Admire Groups, and in alluvial and terrace deposits associated with the major streams. The aquifer boundaries, hydraulic conductivity and recharge values, and ground-water level elevation contours are from previously published reports.

  7. Ambient Flow and Heterogeneity in Multi-Aquifer Wells

    NASA Astrophysics Data System (ADS)

    Hart, D. J.; Gotkowitz, M. B.; Luczaj, J. A.

    2009-12-01

    Multi-aquifers wells, those wells that are open to more than one aquifer, have the potential to allow large quantities of flow between aquifers. Observed rates and direction of intra-borehole flow are often complex, reflecting the heterogeneity of the aquifers and variation of farfield heads. Spinner flow logs collected from several multi-aquifer wells in southern and eastern Wisconsin indicate the importance of flows through these wells in groundwater flow systems. The Paleozoic geology of Wisconsin, composed of more-or-less flat-lying sandstones, dolomites, and shales, gives rise to layered aquifer-aquitard systems where multi-aquifer wells are relatively common. A comparison of the flows in three multi-aquifer wells that cross the Wisconsin’s Paleozoic units showed heterogeniety in aquifers commonly thought to be homogeneous. Variation of the intra-borehole flow in a well gives an indication of heterogeneity and farfield heads in the aquifers. In the first example, the system was relatively simple, consisting of an aquitard (Eau Claire shale) between an upper aquifer (Wonewoc sandstone) and a lower aquifer (Mt Simon sandstone). Heads in the upper aquifer are higher than those in the lower aquifer. In this well, flows gradually increased with depth in the upper aquifer, remained constant in the aquitard, and then gradually decreased with depth in the lower aquifer. The gradual changes indicate relatively homogenous upper and lower aquifers. In the second example, the system also consisted of an aquitard (Tunnel City Group) between an upper aquifer (Sinnipee dolomite and the St. Peter sandstone) and a lower aquifer (Elk Mound Ground). As in the first example, heads in the upper aquifer are greater than those in the lower sandstone aquifer. In contrast to the first example, there were abrupt changes in intra-borehole flow in the upper aquifer, sometimes of more than 180 liters/minute over an interval of less than a meter. Caliper and television logging showed

  8. 40 CFR 147.2752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.2752 Section 147.2752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS....2752 Aquifer exemptions....

  9. 40 CFR 147.252 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.252 Section 147.252 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  10. 40 CFR 147.1202 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1202 Section 147.1202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  11. 40 CFR 147.252 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.252 Section 147.252 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  12. 40 CFR 147.2752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.2752 Section 147.2752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS....2752 Aquifer exemptions....

  13. 40 CFR 147.752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.752 Section 147.752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  14. 40 CFR 147.1402 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.1402 Section 147.1402 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  15. 40 CFR 147.502 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.502 Section 147.502 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  16. 40 CFR 147.902 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.902 Section 147.902 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  17. 40 CFR 147.2752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.2752 Section 147.2752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS....2752 Aquifer exemptions....

  18. 40 CFR 147.1402 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.1402 Section 147.1402 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  19. 40 CFR 147.1402 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1402 Section 147.1402 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  20. 40 CFR 147.902 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.902 Section 147.902 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  1. 40 CFR 147.2752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.2752 Section 147.2752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS....2752 Aquifer exemptions....

  2. 40 CFR 147.2152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.2152 Section 147.2152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  3. 40 CFR 147.2752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.2752 Section 147.2752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS....2752 Aquifer exemptions....

  4. 40 CFR 147.252 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.252 Section 147.252 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  5. 40 CFR 147.1402 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.1402 Section 147.1402 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  6. 40 CFR 147.2152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.2152 Section 147.2152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  7. 40 CFR 147.1402 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.1402 Section 147.1402 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  8. 40 CFR 147.1302 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1302 Section 147.1302 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  9. 40 CFR 147.752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.752 Section 147.752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  10. 40 CFR 147.902 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.902 Section 147.902 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  11. 40 CFR 147.1802 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1802 Section 147.1802 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  12. 40 CFR 147.2852 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.2852 Section 147.2852 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Pacific Islands § 147.2852 Aquifer exemptions....

  13. 40 CFR 147.2152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.2152 Section 147.2152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  14. 40 CFR 147.1302 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.1302 Section 147.1302 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  15. 40 CFR 147.452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.452 Section 147.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... § 147.452 Aquifer exemptions....

  16. 40 CFR 147.152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.152 Section 147.152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  17. 40 CFR 147.252 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.252 Section 147.252 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  18. 40 CFR 147.1302 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.1302 Section 147.1302 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  19. 40 CFR 147.152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.152 Section 147.152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  20. 40 CFR 147.1152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.1152 Section 147.1152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  1. 40 CFR 147.2852 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.2852 Section 147.2852 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Pacific Islands § 147.2852 Aquifer exemptions....

  2. 40 CFR 147.252 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.252 Section 147.252 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  3. 40 CFR 147.652 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.652 Section 147.652 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  4. 40 CFR 147.1302 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.1302 Section 147.1302 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  5. 40 CFR 147.1452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.1452 Section 147.1452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  6. 40 CFR 147.752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.752 Section 147.752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  7. 40 CFR 147.1452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1452 Section 147.1452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  8. 40 CFR 147.1302 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.1302 Section 147.1302 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  9. 40 CFR 147.1802 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.1802 Section 147.1802 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  10. 40 CFR 147.752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.752 Section 147.752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  11. 40 CFR 147.902 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.902 Section 147.902 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  12. 40 CFR 147.2852 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.2852 Section 147.2852 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Pacific Islands § 147.2852 Aquifer exemptions....

  13. 40 CFR 147.1802 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.1802 Section 147.1802 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  14. 40 CFR 147.1202 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.1202 Section 147.1202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  15. 40 CFR 147.452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.452 Section 147.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... § 147.452 Aquifer exemptions....

  16. 40 CFR 147.652 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.652 Section 147.652 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  17. 40 CFR 147.1452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.1452 Section 147.1452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  18. 40 CFR 147.652 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.652 Section 147.652 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  19. 40 CFR 147.2852 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.2852 Section 147.2852 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Pacific Islands § 147.2852 Aquifer exemptions....

  20. 40 CFR 147.152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.152 Section 147.152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  1. 40 CFR 147.502 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.502 Section 147.502 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  2. 40 CFR 147.452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.452 Section 147.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... § 147.452 Aquifer exemptions....

  3. 40 CFR 147.152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.152 Section 147.152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  4. 40 CFR 147.502 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.502 Section 147.502 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  5. 40 CFR 147.1452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.1452 Section 147.1452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  6. 40 CFR 147.1202 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.1202 Section 147.1202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  7. 40 CFR 147.1802 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.1802 Section 147.1802 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  8. 40 CFR 147.1152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.1152 Section 147.1152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  9. 40 CFR 147.2152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.2152 Section 147.2152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  10. 40 CFR 147.2852 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.2852 Section 147.2852 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Pacific Islands § 147.2852 Aquifer exemptions....

  11. 40 CFR 147.902 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.902 Section 147.902 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  12. 40 CFR 147.1202 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.1202 Section 147.1202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  13. 40 CFR 147.152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.152 Section 147.152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  14. 40 CFR 147.2352 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.2352 Section 147.2352 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  15. 40 CFR 147.1802 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.1802 Section 147.1802 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  16. 40 CFR 147.452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.452 Section 147.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... § 147.452 Aquifer exemptions....

  17. 40 CFR 147.1152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.1152 Section 147.1152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  18. 40 CFR 147.2152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.2152 Section 147.2152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  19. 40 CFR 147.1152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.1152 Section 147.1152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  20. 40 CFR 147.752 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.752 Section 147.752 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  1. 40 CFR 147.1152 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.1152 Section 147.1152 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  2. 40 CFR 147.1452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.1452 Section 147.1452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  3. 40 CFR 147.452 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Aquifer exemptions. 147.452 Section 147.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... § 147.452 Aquifer exemptions....

  4. 40 CFR 147.652 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Aquifer exemptions. 147.652 Section 147.652 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  5. 40 CFR 147.502 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.502 Section 147.502 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  6. 40 CFR 147.1202 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Aquifer exemptions. 147.1202 Section 147.1202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  7. 40 CFR 147.652 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Aquifer exemptions. 147.652 Section 147.652 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  8. 40 CFR 147.502 - Aquifer exemptions. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.502 Section 147.502 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Aquifer exemptions....

  9. BIODEGRADATION OF AROMATIC HYDROCARBONS BY AQUIFER MICROORGANISMS UNDER DENITRIFYING CONDITIONS

    EPA Science Inventory

    Laboratory tests were conducted to evaluate whether denitrification would be a suitable alternative for biorestoration of an aquifer contaminated with JP-4 jet fuel. icrocosms were prepared from uncontaminated and contaminated aquifer material, amended with nitrate, nutrients, an...

  10. Project Summary. ANALYTICAL ELEMENT MODELING OF COASTAL AQUIFERS

    EPA Science Inventory

    Four topics were studied concerning the modeling of groundwater flow in coastal aquifers with analytic elements: (1) practical experience was obtained by constructing a groundwater model of the shallow aquifers below the Delmarva Peninsula USA using the commercial program MVAEM; ...

  11. The Oligocene aquifer system in Mississippi

    USGS Publications Warehouse

    Gandl, L.A.

    1979-01-01

    The Oligocene aquifer system in Mississippi consists of limestone and marl members of the Vicksburg Group, and the underlying Forest Hill Sand. The aquifer system crops out in a band 5 to 10 miles wide, that trends southeast across the State from the Warren-Yazoo County line to northeastern Wayne County. In the northwest part of the area, the formations dip to the southwest at 12 feet per mile. At the southeastern end of the outcrop, the dip is 42 feet per mile. The average dip for the entire area is 30 feet per mile. The aquifers are of primary importance for domestic and farm use. Total withdrawal in 1977 was about 1.4 million gallons per day. Since 1963 water levels have declined an average of between 0.05 and 2 feet per year. Water quality is generally good although in some places there are objectionably high concentrations of iron and color. (Woodard-USGS)

  12. Aquifer parameter estimation from surface resistivity data.

    PubMed

    Niwas, Sri; de Lima, Olivar A L

    2003-01-01

    This paper is devoted to the additional use, other than ground water exploration, of surface geoelectrical sounding data for aquifer hydraulic parameter estimation. In a mesoscopic framework, approximated analytical equations are developed separately for saline and for fresh water saturations. A few existing useful aquifer models, both for clean and shaley sandstones, are discussed in terms of their electrical and hydraulic effects, along with the linkage between the two. These equations are derived for insight and physical understanding of the phenomenon. In a macroscopic scale, a general aquifer model is proposed and analytical relations are derived for meaningful estimation, with a higher level of confidence, of hydraulic parameter from electrical parameters. The physical reasons for two different equations at the macroscopic level are explicitly explained to avoid confusion. Numerical examples from existing literature are reproduced to buttress our viewpoint. PMID:12533080

  13. Aquifer Thermal Energy Storage in the US

    NASA Astrophysics Data System (ADS)

    Kannberg, L. D.

    1985-06-01

    DOE has funded investigation of Aquifer Thermal Energy Storage (ATES) since 1975. The scope of the ATES investigation has encompassed numerical modeling, field testing, economic analyses, and evaluation of institutional issues. ATES has received the bulk of the attention because of its widespread potential in the US. US efforts are now concentrated on a high temperature (up to 150C) ATES field test on the St. Paul campus of the University of Minnesota. Four short-term test cycles and the first of two long-term test cycles have been completed at this site. Utilization of chill ATES to meet summer air conditioning demands has been monitored at two operating sites in Tuscaloosa, Alabama. The systems utilize a cooling tower to directly chill groundwater pumped from a water table aquifer for storage in the same aquifer. The first of the two systems has exhibited relatively poor performance. More comprehensive monitoring has recently been undertaken at another site.

  14. Groundwater Mounding in Non-uniform Aquifers with Implications for Managed Aquifer Recharge

    NASA Astrophysics Data System (ADS)

    Zlotnik, V. A.; Noel, P.; Kacimov, A. R.; Al Maktoumi, A. K.

    2015-12-01

    Many areas of the world (e.g. the Middle East and North Africa countries) are deficient in observation networks and hydrogeological data needed for Managed Aquifer Recharge (MAR) design. Therefore, diagnostic analytical approaches are appropriate for feasibility studies of MAR. It was found that the common assumption of aquifer thickness uniformity often does not hold, especially in mountainous watersheds. However, the only practical result available for non-uniform aquifers was developed for well hydraulics applications (point sinks or sources) by Hantush (1962), while the recharge zones may cover large areas on the scale of kilometers, such as temporarily filled impoundments (natural and engineered reservoirs in wadis, depressions, trenches, etc.) or perennial streams accepting massive treated wastewater discharge. To address these important, but overlooked MAR problems in sloping aquifers, a set of new closed-form analytical solutions for water table elevations were obtained. Interestingly, the 2D groundwater flow equation acquires the advection-dispersion equation form in these cases. The quadratures in closed-form solutions obtained by the Green's function method converge rapidly. These models account for both shapes and orientations of sources with respect to the direction of the aquifer base gradient. Qualitatively, solutions in sloping aquifers have an important trait: the mounding is limited in time and space, unlike in aquifers with a horizontal base. Aquifers with the greater slopes have the lesser potential of waterlogging from the rising water table and different storage characteristics (height and volume of locally stored water). Computational aspects of these solutions for MAR analyses are illustrated by example utilizing regional aquifer properties near Az Zarqa River, Jordan. (This study was supported by a grant from USAID-FABRI, project contract: AID-OAA-TO-11-00049, Subcontract: 1001624 -12S-19745).

  15. Aquifer thermal energy storage. International symposium: Proceedings

    SciTech Connect

    1995-05-01

    Aquifers have been used to store large quantities of thermal energy to supply process cooling, space cooling, space heating, and ventilation air preheating, and can be used with or without heat pumps. Aquifers are used as energy sinks and sources when supply and demand for energy do not coincide. Aquifer thermal energy storage may be used on a short-term or long-term basis; as the sole source of energy or as a partial storage; at a temperature useful for direct application or needing upgrade. The sources of energy used for aquifer storage are ambient air, usually cold winter air; waste or by-product energy; and renewable energy such as solar. The present technical, financial and environmental status of ATES is promising. Numerous projects are operating and under development in several countries. These projects are listed and results from Canada and elsewhere are used to illustrate the present status of ATES. Technical obstacles have been addressed and have largely been overcome. Cold storage in aquifers can be seen as a standard design option in the near future as it presently is in some countries. The cost-effectiveness of aquifer thermal energy storage is based on the capital cost avoidance of conventional chilling equipment and energy savings. ATES is one of many developments in energy efficient building technology and its success depends on relating it to important building market and environmental trends. This paper attempts to provide guidance for the future implementation of ATES. Individual projects have been processed separately for entry onto the Department of Energy databases.

  16. Cold water aquifer storage. [air conditioning

    NASA Technical Reports Server (NTRS)

    Reddell, D. L.; Davison, R. R.; Harris, W. B.

    1980-01-01

    A working prototype system is described in which water is pumped from an aquifer at 70 F in the winter time, chilled to a temperature of less than 50 F, injected into a ground-water aquifer, stored for a period of several months, pumped back to the surface in the summer time. A total of 8.1 million gallons of chilled water at an average temperature of 48 F were injected. This was followed by a storage period of 100 days. The recovery cycle was completed a year later with a total of 8.1 million gallons recovered. Approximately 20 percent of the chill energy was recovered.

  17. Epidemiology of endemic goitre in western Colombia

    PubMed Central

    Gaitan, E.; Merino, H.; Rodriguez, G.; Medina, P.; Meyer, J. D.; DeRouen, T. A.; MacLennan, R.

    1978-01-01

    This paper reports on recent epidemiological observations in western Colombia, which further demonstrate the presence of naturally-occurring goitrogens contaminating water supplies in areas where goitre persists despite prolonged and continuous iodine supplementation. 'Prospective' and 'cross-sectional' studies in 41 localities where the populations have been on a uniform and adequate iodine supplementation for the last 10-20 years indicate that, in the endemia of western Colombia, environmental factors other than nutritional iodine deficiency are responsible for differences in goitre prevalence. Further epidemiological studies to determine the causal factors for the persistence of the endemia established a correlation between the sources of drinking water and goitre prevalence rates. Organic compounds containing sulfur with marked thionamide-like antithyroid activity were isolated from water supplying endemic goitre districts, and results are presented supporting the hypothesis that sedimentary rocks rich in organic matter are the main source of water-borne goitrogens. Bacteriological investigations showed that the presence of Klebsiella pneumoniae in drinking water and bacterial concentration were related significantly with goitre prevalence only in the presence of other variables, particularly the presence of sedimentary rocks. In the light of these epidemiological observations and experimental studies it may be concluded that, at present, endemic goitre in western Colombia is not due to nutritional iodine deficiency, but that water supplies are contaminated with sulfur-bearing organic compounds with thionamide-like antithyroid activity most probably deriving from sedimentary rocks rich in organic matter and that these compounds are the main factor underlying the endemia. PMID:80287

  18. Energy resources of Pacific Coast of Colombia

    SciTech Connect

    Bueno Salazar, R.

    1986-07-01

    Despite failure of modest exploration efforts to yield commercial hydrocarbon production in the Choco-Pacific coastal basin of Colombia, recent geophysical, geochemical, and surface geologic investigations indicate a potential for petroleum accumulations, which could be related to fields located on the western basins of Ecuador that in fact constitute an extension of the Colombian Pacific geologic scheme. The Choco-Pacific coastal basin of Colombia covers an area of approximately 70,000 km/sup 2/, of which 14,000 km/sup 2/ lies offshore. The structural style of this area corresponds to a convergent plate basin created over folded oceanic sediments and adjacent to the subduction zone. Such a framework could be conducive to an attractive array of potential hydrocarbon-bearing traps. Geochemical knowledge of potential source rocks of Cretaceous and early Tertiary age confers an added attraction to the area. Most evaluations reveal kerogen-rich, gas-prone organic matter. Nevertheless, the existence of oil seeps from Cretaceous outcrops could indicate sufficient thermal maturity for oil generation. Adequate reservoirs could be found in sandy or calcareous rocks of late Eocene to Oligocene age, predominantly of marine origin with an estimated thickness exceeding 20,000 ft. Colombia has been one of the leading world producers of gold and platinum, mostly derived from the vast alluvial cover of the onshore area of the basin. In rocks cropping out in the Western Cordillera (eastern margin of the basin), deposits of potentially commercial value of porphyry copper and molybdenum, as well as massive sulfur, manganese, and bauxite, have been found.

  19. Ithomiini butterflies (Lepidoptera: Hymphalidae) of Antioquia, Colombia.

    PubMed

    Giraldo, C E; Willmott, K R; Vila, R; Uribe, S I

    2013-04-01

    Colombia is one of the most biodiverse countries on the planet. However, economic and scientific investment in completing inventories of its biodiversity has been relatively poor in comparison with other Neotropical countries. Butterflies are the best studied group of invertebrates, with the highest proportion of known to expected species. More than 3,200 species of butterflies have been recorded in Colombia, although the study of the still many unexplored areas will presumably increase this number. This work provides a list of Ithomiini butterflies collected in the department of Antioquia and estimates the total number of species present, based on revision of entomological collections, records in the literature and field work performed between 2003 and 2011. The list includes 99 species and 32 genera, representing 27% of all Ithomiini species. We report 50 species of Ithomiini not formerly listed from Antioquia, and found the highest diversity of ithomiine species to be at middle elevations (900-1,800 m). The mean value of the Chao2 estimator for number of species in Antioquia is 115 species, which is close to a predicted total of 109 based on known distributions of other Ithomiini not yet recorded from the department. Nine species are potentially of particular conservation importance because of their restricted distributions, and we present range maps for each species. We also highlight areas in Antioquia with a lack of biodiversity knowledge to be targeted in future studies. This paper contributes to mapping the distribution of the Lepidoptera of Antioquia department in particular and of Colombia in general. PMID:23949748

  20. 40 CFR 146.4 - Criteria for exempted aquifers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Criteria for exempted aquifers. 146.4 Section 146.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM: CRITERIA AND STANDARDS General Provisions § 146.4 Criteria for exempted aquifers. An aquifer or...

  1. 40 CFR 146.4 - Criteria for exempted aquifers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Criteria for exempted aquifers. 146.4 Section 146.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM: CRITERIA AND STANDARDS General Provisions § 146.4 Criteria for exempted aquifers. An aquifer or...

  2. Groundwater modeling of the Calera Aquifer region in Central Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Calera Aquifer is the main source of water for irrigated agriculture, industrial, and drinking water purposes in the Calera Aquifer Region (CAR) in the state of Zacatecas, Mexico. Irrigated agriculture accounts for 80% of the total groundwater extracted from the Calera Aquifer. In recent years, ...

  3. 40 CFR 147.3008 - Criteria for aquifer exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Criteria for aquifer exemptions. 147... the Navajo, Ute Mountain Ute, and All Other New Mexico Tribes § 147.3008 Criteria for aquifer exemptions. The aquifer exemption criterion in § 146.4(c) of this chapter shall not be available for...

  4. 40 CFR 147.3008 - Criteria for aquifer exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Criteria for aquifer exemptions. 147... the Navajo, Ute Mountain Ute, and All Other New Mexico Tribes § 147.3008 Criteria for aquifer exemptions. The aquifer exemption criterion in § 146.4(c) of this chapter shall not be available for...

  5. 40 CFR 147.3008 - Criteria for aquifer exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Criteria for aquifer exemptions. 147... the Navajo, Ute Mountain Ute, and All Other New Mexico Tribes § 147.3008 Criteria for aquifer exemptions. The aquifer exemption criterion in § 146.4(c) of this chapter shall not be available for...

  6. 40 CFR 146.4 - Criteria for exempted aquifers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Criteria for exempted aquifers. 146.4... for exempted aquifers. An aquifer or a portion thereof which meets the criteria for an “underground... aquifer” for Class I-V wells if it meets the criteria in paragraphs (a) through (c) of this section....

  7. 40 CFR 147.3008 - Criteria for aquifer exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Criteria for aquifer exemptions. 147... the Navajo, Ute Mountain Ute, and All Other New Mexico Tribes § 147.3008 Criteria for aquifer exemptions. The aquifer exemption criterion in § 146.4(c) of this chapter shall not be available for...

  8. 40 CFR 147.3008 - Criteria for aquifer exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Criteria for aquifer exemptions. 147... the Navajo, Ute Mountain Ute, and All Other New Mexico Tribes § 147.3008 Criteria for aquifer exemptions. The aquifer exemption criterion in § 146.4(c) of this chapter shall not be available for...

  9. 40 CFR 146.4 - Criteria for exempted aquifers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Criteria for exempted aquifers. 146.4... for exempted aquifers. An aquifer or a portion thereof which meets the criteria for an “underground... aquifer” for Class I-V wells if it meets the criteria in paragraphs (a) through (c) of this section....

  10. Examples of transient sounding from groundwater exploration in sedimentary aquifers

    USGS Publications Warehouse

    Fitterman, D.V.

    1987-01-01

    Examples of the use of transient electromagnetic soundings for three groundwater exploration problems in sedimentary aquifers are given. The examples include: 1) estimating depths to water table and bedrock in an alluvium-filled basin, 2) mapping a confined freshwater aquifer in bedrock sediments, and 3) locating a freshwater/saltwater interface in a glacial-outwash aquifer. -from Author

  11. Aquifer susceptibility in Virginia, 1998-2000

    USGS Publications Warehouse

    Nelms, David L.; Harlow,, George E., Jr.; Plummer, L. Niel; Busenberg, Eurybiades

    2003-01-01

    The U.S. Geological Survey (USGS), in cooperation with the Virginia Department of Health, sampled water from 171 wells and springs across the Commonwealth of Virginia between 1998 and 2000 as part of the Virginia Aquifer Susceptibility study. Most of the sites sampled are public water supplies that are part of the comprehensive Source Water Assessment Program for the Commonwealth. The fundamental premise of the study was that the identification of young waters (less than 50 years) by multiple environmental tracers could be used as a guide for classifying aquifers in terms of susceptibility to contamination from near-surface sources. Environmental tracers, including chlorofluorocarbons (CFCs), sulfur hexafluoride (SF6), tritium (3H), and tritium/helium-3 (3H/3He), and carbon isotopes (14C and d13C) were used to determine the age of water discharging from wells and springs. Concentrations of CFCs greater than 5 picograms per kilogram and 3H concentrations greater than 0.6 tritium unit were used as thresholds to indicate that parts of the aquifer sampled have a component of young water and are, therefore, susceptible to near-surface contamination. Concentrations of CFCs exceeded the susceptibility threshold in 22 percent of the wells and in one spring sampled in the Coastal Plain regional aquifer systems. About 74 percent of the samples from wells with the top of the first water zone less than 100 feet below land surface exceeded the threshold values, and water supplies developed in the upper 100 feet of the Coastal Plain are considered to be susceptible to contamination from near-surface sources. The maximum depth to the top of the screened interval for wells that contained CFCs was less than 150 feet. Wells completed in the deep confined aquifers in the Coastal Plain generally contain water older than 1,000 years, as indicated by carbon-14 dating, and are not considered to be susceptible to contamination under natural conditions. All of the water samples from wells

  12. Aquifer geochemistry at potential aquifer storage and recovery sites in coastal plain aquifers in the New York city area, USA

    USGS Publications Warehouse

    Brown, C.J.; Misut, P.E.

    2010-01-01

    The effects of injecting oxic water from the New York city (NYC) drinking-water supply and distribution system into a nearby anoxic coastal plain aquifer for later recovery during periods of water shortage (aquifer storage and recovery, or ASR) were simulated by a 3-dimensional, reactive-solute transport model. The Cretaceous aquifer system in the NYC area of New York and New Jersey, USA contains pyrite, goethite, locally occurring siderite, lignite, and locally varying amounts of dissolved Fe and salinity. Sediment from cores drilled on Staten Island and western Long Island had high extractable concentrations of Fe, Mn, and acid volatile sulfides (AVS) plus chromium-reducible sulfides (CRS) and low concentrations of As, Pb, Cd, Cr, Cu and U. Similarly, water samples from the Lloyd aquifer (Cretaceous) in western Long Island generally contained high concentrations of Fe and Mn and low concentrations of other trace elements such as As, Pb, Cd, Cr, Cu and U, all of which were below US Environmental Protection Agency (USEPA) and NY maximum contaminant levels (MCLs). In such aquifer settings, ASR operations can be complicated by the oxidative dissolution of pyrite, low pH, and high concentrations of dissolved Fe in extracted water.The simulated injection of buffered, oxic city water into a hypothetical ASR well increased the hydraulic head at the well, displaced the ambient groundwater, and formed a spheroid of injected water with lower concentrations of Fe, Mn and major ions in water surrounding the ASR well, than in ambient water. Both the dissolved O2 concentrations and the pH of water near the well generally increased in magnitude during the simulated 5-a injection phase. The resultant oxidation of Fe2+ and attendant precipitation of goethite during injection provided a substrate for sorption of dissolved Fe during the 8-a extraction phase. The baseline scenario with a low (0.001M) concentration of pyrite in aquifer sediments, indicated that nearly 190% more water

  13. Hydrogeochemical Analysis of an Overexploited Aquifer In Bangladesh Toward Managed Aquifer Recharge Project Implementation

    NASA Astrophysics Data System (ADS)

    Rahman, M. A.; Wiegand, B. A.; Pervin, M.; Sauter, M.

    2012-12-01

    In most parts of the upper Dupitila aquifer (Dhaka City, Bangladesh) the average groundwater depletion reaches 2-3 m/year due to increasing water demands of the growing population. To counteract overexploitation of the aquifer, a more sustainable water management is required. The analysis of the local water resources system suggests that Managed Aquifer Recharge (MAR) would help to restore groundwater resources to strengthen water supply of Dhaka City, e.g., by using collected urban monsoon runoff and excess surface water from rivers. To assess possible effects of surface water or rainwater injection on groundwater quality, a comprehensive hydrogeochemical survey of the Dupitila aquifer is required. This paper presents hydrogeochemical data to document the current status of groundwater quality and to evaluate potential groundwater pollution by mobilization of hazardous chemicals as a result of changes in the hydrochemical equilibria. We performed a comprehensive review of available secondary data sources and will present new results from hydrochemical and Sr isotope investigations of water samples that were conducted within this study. Currently, groundwater quality in the upper Dupitila aquifer is characterized by variations in the electrical conductivity in the range of 200 to 1100 μS/cm, which may indicate some anthropogenic contamination by leakage from waste disposal including the sewage network and from surface water infiltration into the groundwater aquifer. Dissolved oxygen concentrations range from 1.0 to 4.9 mg/L (average 2.5 mg/L) in the upper Dupitila aquifer, while the lower Dupilita aquifer shows dissolved oxygen concentrations in the range 0 to 0.7 mg/L. Concentrations of major ions show some variation primarily due to a sedimentologically/mineralogically heterogeneous aquifer composition (sand, gravel, clay horizons), but may also be affected by anthropogenic processes. The groundwater composition is predominated by Ca-Mg-HCO3 and saturation values

  14. Digital data set that describe aquifer characteristics of the Antlers aquifer in southeastern Oklahoma

    USGS Publications Warehouse

    Abbott, Marvin M.; Runkle, D.L.; Rea, Alan

    1997-01-01

    ARC/INFO export and nonproprietary format file This diskette contains digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Antlers aquifer in southeastern Oklahoma. The Early Cretaceous-age Antlers Sandstone is an important source of water in an area that underlies about 4,400-square miles of all or part of Atoka, Bryan, Carter, Choctaw, Johnston, Love, Marshall, McCurtain, and Pushmataha Counties. The Antlers aquifer consists of sand, clay, conglomerate, and limestone in the outcrop area. The upper part of the Antlers aquifer consists of beds of sand, poorly cemented sandstone, sandy shale, silt, and clay. The Antlers aquifer is unconfined where it outcrops in about an 1,800-square-mile area. The recharge, hydraulic conductivity, and aquifer boundaries data sets include the outcrop area of the Antlers Sandstone in Oklahoma and areas where the Antlers is overlain by alluvial and terrace deposits and a few small thin outcrops of the Goodland Limestone. Most of the lines in these data sets were extracted from published digital geology data sets. Some of the lines were interpolated in areas where the Antlers aquifer is overlain by alluvial and terrace deposits near streams and rivers. The interpolated lines are very similar to the aquifer boundaries published in a ground-water modeling report for the Antlers aquifer. The maps from which this data set was derived were scanned or digitized from maps published at a scale of 1:250,000. The water-level elevation contours were digitized from a map at a scale of 1:250,000 that was used to prepare the final map published in a ground-water flow model report. Hydraulic conductivity and recharge values also are published in the ground-water model report for the Antlers aquifer. Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may

  15. Digital data sets that describe aquifer characteristics of the High Plains Aquifer in western Oklahoma

    USGS Publications Warehouse

    Becker, C.J.; Runkle, D.L.; Rea, Alan

    1997-01-01

    ARC/INFO export files This diskette contains digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the High Plains aquifer in western Oklahoma. This area encompasses the panhandle counties of Cimarron, Texas, and Beaver, and the western counties of Harper, Ellis, Woodward, Dewey, and Roger Mills. The High Plains aquifer underlies approximately 7,000 square miles of Oklahoma and is used extensively for irrigation. The High Plains aquifer is a water-table aquifer and consists predominately of the Tertiary-age Ogallala Formation and overlying Quaternary-age alluvial and terrace deposits. In some areas the aquifer is absent and the underlying Triassic, Jurassic, or Cretaceous-age rocks are exposed at the surface. These rocks are hydraulically connected with the aquifer in some areas. The High Plains aquifer is composed of interbedded sand, siltstone, clay, gravel, thin limestones, and caliche. The proportion of various lithological materials changes rapidly from place to place, but poorly sorted sand and gravel predominate. The rocks are poorly to moderately well cemented by calcium carbonate. The aquifer boundaries, hydraulic conductivity, and recharge data sets were created by extracting geologic contact lines from published digital surficial geology maps based on a scale of 1:125,000 for the panhandle counties and 1:250,000 for the western counties. The water-level elevation contours and some boundary lines were digitized from maps in a published water-level elevation map for 1980 based on a scale of 1:250,000. The hydraulic conductivity and recharge values in this report were used as input to the ground-water flow model on the High Plains aquifer. Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may produce similar results. Therefore, values of hydraulic conductivity and

  16. Groundwater ages in fractured rock aquifers

    NASA Astrophysics Data System (ADS)

    Cook, P. G.; Love, A. J.; Robinson, N. I.; Simmons, C. T.

    2005-07-01

    In fractured porous media, matrix diffusion processes mean that groundwater ages obtained with environmental tracers usually do not reflect the hydraulic age of the water. The distribution of groundwater ages within these heterogeneous systems will be related to the groundwater velocity within the fractures, but also to the size of the fractures and the geometry of the fracture network, and to the hydraulic properties of the aquifer matrix. In this paper, we present analytical and numerical simulations of environmental tracer concentrations in fractured rock aquifers to examine the effect of changes in aquifer parameters on the tracer distributions. In particular, we show that where horizontal fractures are strongly vertically connected, then it may be reasonable to use one-dimensional models of flow and transport through vertical fractures to represent flow through aquifers containing both horizontal and vertical fractures. The presence of large numbers of horizontal fractures will not cause flow to depart significantly from the one-dimensional approximation. Where a smaller number of horizontal fractures are present, then abrupt decreases in the vertical water velocity can occur, as water is intercepted and diverted laterally. Measurements of 14C, 3H, 36Cl, and chlorofluorocarbons within nested piezometers from the Clare Valley, South Australia, display a number of the features apparent in the generic simulations. The use of a number of different tracers appears to allow some fracture and matrix parameters to be constrained more tightly than might previously have been thought possible.

  17. PREDICTING CONTAMINANT MIGRATION IN KARST AQUIFERS

    EPA Science Inventory

    Time-of-travel transport estimation is employed to predict contaminant migration in karst aquifers. stimation of time-of-travel transport is conditioned on the set of hydraulic-flow and geometric parameters that describe different transport processes that occur within karst condu...

  18. Tertiary Aquifer Modeling Within the Mississippi Embayment

    NASA Astrophysics Data System (ADS)

    Csontos, R.; Waldron, B.; Anderson, J.

    2008-12-01

    The geologic and hydrogeologic characterization of the aquifers and their recharge area within the Central United States in west Tennessee, northern Mississippi and eastern Arkansas are poorly understood. Previous investigations have utilized overly generalized outcrop boundaries of the primary Tertiary aquifers based on sparse well log information and stream down-cutting to show formation location. Acquisition of data in the form of deep oil and gas wells along with shallow lignite borehole data from the North American Coal Company is enabling us to improve upon these prior formational boundaries and recharge area delineations. Additionally, utilization of those geophysical logs with numerous well log curves is allowing us to characterize each geologic unit as to the sand/clay composition, porosity, and depiction of facies changes within a three- dimensional context. This is made possible through the utilization of the oil industry standard mapping package, Petrel®. We use a combination of methods to illustrate the presence of clay bodies within the primary drinking water aquifer, historically modeled solely as a sand unit. Identification of these clay bodies will impact ground-water flow patterns and assist water utilities in reducing contamination threats. We will illustrate aquifer thickness variability owning to faulting and paleo-erosion that again may impact ground-water pathways.

  19. Managing environmental problems in Cuban karstic aquifers

    NASA Astrophysics Data System (ADS)

    León, Leslie Molerio; Parise, Mario

    2009-07-01

    The Cuban archipelago hosts some of the most typical karst features in the Caribbean, and has very important and high-quality resources of karst water. Carbonate rocks cover about 70% of the country area, with a great variety of karst features, and outstanding exokarstic landforms such as the cone karst; in addition, many caves are regarded as cultural and historical sites. Protection of the karst hydric resources is therefore essential. In karst, the intrinsic vulnerability of the environment makes it highly susceptible to pollution, which may result in dramatic consequences for both the quality of karst water and the amount of water available. Many anthropogenic activities produce negative changes in the karst aquifers, in some cases with unrecoverable effects. In Cuba, five main sources of pollution to karst aquifers have been identified: sea water intrusion, agricultural practices, waste disposal, industrial activity, and mining and oil production. Due to the narrow and elongated configuration of the main island, wide portions of the territory are mostly affected by seawater intrusion problems, exacerbated by the concentration of both population and human activities in the largest towns located along, or very close to, the coasts. Seawater intrusion, however, is not the only source of pollution for Cuban karst aquifers. The other aforementioned sources are important, and may locally prevail (e.g. pollution resulting from sugar cane factories). Considerations on the management of karst aquifers and a brief description of the water quality monitoring system of Cuban inland waters are also provided.

  20. STUDY OF THE ARBUCKLE-SIMPSON AQUIFER

    EPA Science Inventory

    A study directed by the Oklahoma Water Resources Board and funded by the U.S. Bureau of Reclamation will investigate the hydrogeology of the Arbuckle-Simpson Aquifer in south-central Oklahoma. The five year study will involve field investigations including the installation of ne...

  1. Steady state phreatic surfaces in sloping aquifers

    NASA Astrophysics Data System (ADS)

    LoáIciga, Hugo A.

    2005-08-01

    Steady state groundwater flow driven by constant recharge in an unconfined aquifer overlying sloping bedrock is shown to be represented, using the Dupuit approximation, by an ordinary differential equation of the Abel type y(x) · y'(x) + a · y(x) + x = 0, whose analytical solution is derived in this work. This article first investigates the case of zero saturated thickness at the upstream boundary, a flow system reminiscent of perched groundwater created by percolation of precipitation or irrigation in a sloping aquifer fully draining at its downstream boundary. A variant of this flow system occurs when the phreatic surface mounds and produces groundwater discharge toward the upstream boundary. This variant is a generalization of the classical groundwater flow problem involving two lakes connected by an aquifer, the latter being on sloping terrain in this instance. Analytical solutions for the phreatic surface's steady state geometry are derived for the case of monotonically declining hydraulic head as well as for the case of a mounded phreatic surface. These solutions are of practical interest in drainage studies, slope stability, and runoff formation investigations. It is shown that the flow factor a = -? tan β (where K, N, and tan β are the hydraulic conductivity, vertical recharge, and aquifer slope, respectively) has a commanding role on the phreatic surface's solutions. Two computational examples illustrate the implementation of this article's results.

  2. Steady state phreatic surfaces in sloping aquifers

    NASA Astrophysics Data System (ADS)

    Loáiciga, Hugo A.

    2005-08-01

    Steady state groundwater flow driven by constant recharge in an unconfined aquifer overlying sloping bedrock is shown to be represented, using the Dupuit approximation, by an ordinary differential equation of the Abel type y(x) . y'(x) + a . y(x) + x = 0, whose analytical solution is derived in this work. This article first investigates the case of zero saturated thickness at the upstream boundary, a flow system reminiscent of perched groundwater created by percolation of precipitation or irrigation in a sloping aquifer fully draining at its downstream boundary. A variant of this flow system occurs when the phreatic surface mounds and produces groundwater discharge toward the upstream boundary. This variant is a generalization of the classical groundwater flow problem involving two lakes connected by an aquifer, the latter being on sloping terrain in this instance. Analytical solutions for the phreatic surface's steady state geometry are derived for the case of monotonically declining hydraulic head as well as for the case of a mounded phreatic surface. These solutions are of practical interest in drainage studies, slope stability, and runoff formation investigations. It is shown that the flow factor a = -$\\sqrt{{\\rm K}/{\\rm N} tan β (where K, N, and tan β are the hydraulic conductivity, vertical recharge, and aquifer slope, respectively) has a commanding role on the phreatic surface's solutions. Two computational examples illustrate the implementation of this article's results.

  3. Groundwater sustainability assessment in coastal aquifers

    NASA Astrophysics Data System (ADS)

    Lathashri, U. A.; Mahesha, A.

    2016-08-01

    The present work investigates the response of shallow, coastal unconfined aquifers to anticipated overdraft conditions and climate change effect using numerical simulation. The groundwater flow model MODFLOW and variable density groundwater model SEAWAT are used for this investigation. The transmissivity and specific yield estimated from the existing database range from 10 to 810 m 2/day and 0.08% to 10.92% respectively. After successful calibration with Nash-Sutcliffe efficiency greater than 0.80, the values of horizontal hydraulic conductivity and specific yield of the unconfined aquifer were set in the range 1.85-61.90 m/day and 0.006-0.24 respectively. After validating the model, it is applied for forecasting the aquifer's response to anticipated future scenarios of groundwater draft, recharge rate and sea level rise. The findings of the study illustrate that saltwater intrusion is intensified in the area adjoining the tidal rivers, rather than that due to the sea alone. Of all the scenarios simulated, the immense negative impact on groundwater quality emerges due to overdraft conditions and reduced recharge with the areal extent of seawater intrusion exceeding about 67% (TDS >1 kg/m 3). The study also arrives at the conclusion that, regional sea level rise of 1 mm/year has no impact on the groundwater dynamics of the aquifer.

  4. NORTHERN GUAM SOLE SOURCE AQUIFER- DESIGNATED AREA

    EPA Science Inventory

    Northern Guam Sole Source Aquifer Designated Area: In the Territory of Guam, entirely contained within the island of Guam. Specifically, that area within the coastal boundary defined by the line of Mean High water and north of the Adelup-Pago fault, plus some area south of the f...

  5. Oxidation-reduction capacities of aquifer solids

    SciTech Connect

    Barcelona, M.J.; Holm, T.R.

    1991-01-01

    Oxidation-reduction processes play a major role in the mobility, transport, and fate of inorganic and organic chemical constituents in natural waters. Therefore, the manipulation of redox conditions in natural and treated water systems is assumed to be a common option for the control of contaminant concentrations. Measurements of the oxidation (i.e., of aqueous Cr(2+)) and reduction (i.e., of aqueous Cr2O7(2-) and H2O2) capacities of aquifer solids and groundwater have been made on samples from a sand-and-gravel aquifer. The groundwater contributed less than 1% of the system oxidation or reduction poising capacity. Reduction capacities averaged 0.095, 0.111, and 0.136 mequiv/g of dry solids for oxic, transitional, and reducing Eh conditions, respectively. Measured oxidation capacities averaged 0.4 mequiv/g of dry solids over the range of redox intensity conditions. These capacities represent considerable resistance to the adjustment of redox conditions even at uncontaminated sites. Hydrogen peroxide reduction by aquifer solid samples proceeds rapidly relative to microbially mediated decomposition. The study indicates the need for closer scrutiny of the predictability and cost effectiveness of attempts to manipulate redox conditions in poorly poised aquifer systems.

  6. The Coffee Sand and Ripley aquifers in Mississippi

    USGS Publications Warehouse

    Boswell, E.H.

    1978-01-01

    The Coffee Sand and Ripley aquifers, of Cretaceous age, are in the Selma Group in northern Mississippi. The aquifers contain freshwater in an area of about 4,400 square miles in northern Mississippi. Water produced from the aquifers by public water systems and numerous industries in 1975 averaged about 4 Mgal/d. Regional water-level declines have been very small and the aquifers have a moderate potential for future development. The aquifers are used in some areas where there are no other significant sources of ground water. The most common problems in developing water supplies are low yields to wells and hard water. (Kosco-USGS)

  7. Tuberculosis control and managed competition in Colombia.

    PubMed

    Arbelaez, Maria Patricia; Gaviria, Marta Beatriz; Franco, Alvaro; Restrepo, Roman; Hincapié, Doracelly; Blas, Erik

    2004-01-01

    Law 100 introduced the Health Sector Reform in Colombia, a model of managed competition. This article addresses the effects of this model in terms of output and outcomes of TB control. Trends in main TB control indicators were analysed using secondary data sources, and 25 interviews were done with key informants from public and private insurers and provider institutions, and from the health directorate level. We found a deterioration in the performance of TB control: a decreasing number of BCG vaccine doses applied, a reduction in case finding and contacts identification, low cure rates and an increasing loss of follow up, which mainly affects poor people. Fragmentation occurred as the atomization and discontinuity of the technical processes took place, there was a lack of coordination, as well as a breakdown between individual and collective interventions, and the health information system began to disintegrate. The introduction of the Managed Competition (MC) in Colombia appeared to have adverse effects on TB control due to the dominance of the economic rationality in the health system and the weak state stewardship. Our recommendations are to restructure the reform's public health component, strengthen the technical capacity in public health of the state, mainly at the local and departmental levels, and to improve the health information system by reorienting its objectives to public health goals. PMID:15686059

  8. Colombia: crusading efforts bring signs of progress.

    PubMed

    Kendall, S

    1989-01-01

    Colombia, like many developing countries, has not committed resources to fight the AIDS problem. They have used the media for condom promotion and other sexually transmitted diseases. There have been 151 deaths caused by AIDS by the end of 1988; 344 cases are known, and 130 additional have tested positive to the virus. Health officials were reluctant to recognize the problem, thinking it was outside their country and that they would not be affected by it. Since then, they have tried to target high risk groups and educate them and assist with testing and counseling. There is a move to make the new drug zidovudine available, but few could afford its high price. The authorities have put transvestite prostitutes in jail and kept them for AIDS testing, but few woman prostitutes have been tested. Up until 1986, only 30% of the Red Cross blood bank supplies were being tested; now 80% are, although it comprises only about 40% of the total supply. Drugs are used heavily, but mostly smoked, in Colombia, yet there is some concern about increased use of needles. The majority of cases in Columbia have been homosexual and bisexual men, but prostitution among men and women is prevalent in large cities such as Bogota. Health officials state that education is the best deterrent, but must be perpetuated so people will be constantly reminded. PMID:12282910

  9. Delineation and description of the regional aquifer systems of Tennessee; Cumberland Plateau aquifer system

    USGS Publications Warehouse

    Brahana, J.V.; Macy, J.A.; Mulderink, Dolores; Zemo, Dawn

    1986-01-01

    The Cumberland Plateau aquifer system consists of Pennsylvanian sandstones, conglomerates, shales, and coals which underlie the Cumberland Plateau in Tennessee. Major water-bearing zones occur within the sandstones and conglomerates in interconnected fractures. The water-bearing formations are separated by shale and siltstone that retard the vertical circulation of ground water, The Pennington Formation serves as the base of this aquifer system and is an effective confining unit, The Cumberland Plateau aquifer system is an important water source for the Cumberland Plateau, wells and springs from the aquifer system supply most of the rural domestic and public drinking-water supplies, water from wells drilled into the Cumberland Plateau aquifer system is generally of good to excellent quality. Of the 32 water-quality analyses on file from this aquifer. only 2 had dissolved-solids concentrations greater than 500 milligrams per liter, and about three-fourths had less than 200 milligrams per liter dissolved solids, However, no samples from depths greater than 300 feet below land surface have been recorded. Ground water from locations where the sandstones are buried deeply, such as the Wartburg basin, may contain dissolved-solids concentrations greater than 1,000 milligrams per liter.

  10. Preliminary delineation and description of the regional aquifers of Tennessee : Cumberland Plateau aquifer system

    USGS Publications Warehouse

    Brahana, J.V.; Macy, Jo Ann; Mulderink, Dolores; Zemo, Dawn

    1986-01-01

    The Cumberland Plateau aquifer system consists of Pennsylvanian sandstones, conglomerates, shales, and coals which underlie the Cumberland Plateau in Tennessee. Major water-bearing zones occur within the sandstones and conglomerates in interconnected fractures. The water-bearing formations are separated by shale and siltstone that retard the vertical circulation of ground water. The Pennington Formation serves as the base of this aquifer system and is an effective confining unit. The Cumberland Plateau aquifer system is an important water source for the Cumberland Plateau. Wells and springs from the aquifer system supply most of the rural domestic and public drinking-water supplies. Water from wells drilled into the Cumberland Plateau aquifer system is generally of good to excellent quality. Of the 32 water-quality analyses on file from this aquifer, only 2 had dissolved-solids concentrations greater than 500 milligrams per liter, and about three-fourths had less than 200 milligrams per liter dissolved solids. However, no samples from depths greater than 300 feet below land surface have been recorded. Ground water from locations where the sandstones are buried deeply, such as the Wartburg basin, may contain dissolved-solids concentrations greater than 1,000 milligrams per liter.