ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02740.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTMicrobial contamination of ground water results in numerous disease outbreaks each year. Tracing their movement in ground water is therefore essential. Bacteria, viruses, yeasts and spores have been used for this purpose and to trace underground movement of water in much the same manner as chemical tracers are used. Chemical tracers do not always reflect the movement of microorganisms in ground water. The use of certain bacteria and animal viruses is undesirable due to their pathogenic potential and difficulties in their differentiation from background, naturally‐occurring organisms. Bacterial viruses appear to be the microorganisms most suited as a microbial tracer because of their size, ease of assay and lack of pathogenicity. Bacteriophages have been used to trace ground‐water movement over distances of 1,600 meters and can be used under a variety of conditi

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02741.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTA numerical simulation and analytical study of a constant‐rate pumping test, for a well situated at the centre of a disc of anomalous transmissivity and storage coefficient, have been used to aid in the interpretation of tests performed in a “patchy” aquifer in India. Equations describing the long‐time behaviour of drawdown show that Jacob's method can be employed to estimate the regional transmissivity from drawdowns measured at any point in the aquifer or in the pumping well. However, these equations also show that an average storage coefficient should be calculated from drawdowns measured outside the aquifer discontinuity.The results of this study support the hypothesis that the average transmissivity of a heterogeneous aquifer can be calculated from rates of drawdown observed after long periods of

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02742.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTTwo programs are given for the CASIO FX‐502 programmable calculator for direct computation of transmissivity and storativity from time‐drawdown and distance‐drawdown data. These aquifer parameters are calculated from Jacob's modification of the Theis equation by the least squares' method. The programs also calculate drawdowns at various times and distances using the computed transmissivity and storat

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02743.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTSoils underlain at shallow depths (less than 1 m, 3 ft) by glacial till are generally considered undesirable for irrigation because of their unfavourable internal drainage characteristics. In some areas of southern Alberta, Canada, soils developed upon shallow tills have been irrigated successfully for over 60 years with no adverse effects on the soil. An investigation was conducted to describe the hydro‐geologic properties of till under one of these areas and to assess the properties with regard to drainage. Study techniques consisted of detailed test drilling and sampling, excavation of test pits, installation and monitoring of ground‐water instrumentation, field and laboratory hydraulic conductivity testing and tritium analyses of ground‐water samples. Two fracture sets were found in this till. Both sets of fractures produce secondary permeabilities which mask the low hydraulic conductivity of the till matrix (10−10m·s−1). Small‐scale fractures which have a fracture spacing of approximately 10 mm (0.4 in.) have an apparent mean hydraulic conductivity of 5 × 10−9m·s−1, whereas large‐scale fractures which have fracture spacings from 20 mm (0.8 in.) to over 630 mm(2 ft) have an apparent mean hydraulic conductivity of approximately 2 × 10−7m·s−1. The high hydraulic conductivity of the large‐scale fractures was corroborated by tritium analyses of ground‐water samples. Tritium analyses also indicate the presence of recent water at depth in the till. The large‐scale fractures, which control the bulk hydraulic conductivity of this till, provide conduits through which infiltrating water can be transmitted to the ground‐water regime. These fractures are believed to be the reason why this land has re

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02744.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTMeager Mountain is a recently‐active andesite‐dacite volcano situated 160 km NNW of Vancouver, British Columbia. The mountain is presently being jointly evaluated by the Geological Survey of Canada and the British Columbia Hydro and Power Authority as a potential geo‐thermal resource. Limited existing and field‐generated geological and hydrogeological data were employed to evaluate the ground‐water flow regime at the study area. Mathematical modeling was carried out to determine the feasible range of ground‐water‐flow characteristics in the area. Field observations indicate that the water table is located at an intermediate elevation in the mountain system with the discharge area confined to the portion of the valley covered by unconsolidated deposits. Water balance calculations for the Lillooet River basin and baseflow determinations in the Meager Creek basin indicate that 14 to 17% of the total precipitation recharges the ground‐water system. Various possible geological configurations were mathematically modeled with the water‐table configuration and recharge rates restricted to the above ranges. The model results were used to predict the variations in the hydraulic conductivity in each geological formation. The results fell into a discrete range of values thought to be within an order of magnitude of

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02745.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTIn 1977, the Island Water Association (IWA) on Sanibel Island, Florida, was concerned that the total dissolved solids concentrations in several wells in its well field were increasing and might cause the blended raw water to exceed the design capacity of its electrodialysis plant. Test wells were drilled several miles west of the existing well field, and two pumping tests, one at the site of the test wells and the other in the existing well field, were run. Average values for the transmissivity (T), storage coefficient (S), and leakance (K′/b′) of the lower Hawthorn aquifer were determined to be T = 1,290 ft2/d (119 m2/d), S = 2.7 × 10−5, and K′/b′= 7.47 × 10−6(1/d). The results of the pumping tests and other findings indicated that pumpage from the lower Hawthorn aquifer was being derived from artesian storage in the aquifer and from vertical leakage into the aquifer from adjacent formations. It was estimated that the IWA would be able to recover usable water from the lower Hawthorn aquifer for about 5 more years by drilling new wells in the vicinity of the test wells and in other nearby areas that might be determined to yield usable water. After this period of time, it likely would become increasingly difficult, if not impossible, to obtain large quantities of usable water from the lower Hawthorn aquifer, unless significant quantities of water could be found in areas in which few data were then available. The principal recommendations, which subsequently were acted upon by the IWA, were to conduct drilling and testing in the lower Hawthorn aquifer several miles west of the test wells and to investigate the underlying Suwannee aquifer and deeper zones as possible sources of large quantities of b

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02746.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTIn the design of ground‐water heat pump systems the quantitative analysis of heat transport and heat storage is of great interest. A unified finite element approach to the transient nonlinear heat transport and heat storage problem is presented. The theory presented includes nonlinear physical properties and boundary conditions, coupled conductive and convective heat flow, freezing (phase change), and time‐dependent heat input and output. The given theory is applied to two problems. The first problem is a transient study during a few years of heat storage in saturated clay. A pure conductive theory is used due to the small amount of convective water flow in clay. The second problem deals with transient heat transport in an aquifer according to coupled conduction‐convection theory on a one‐dimensional model

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02747.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTWater quality data collected from monitoring wells in the Piceance Creek Basin oil shale area can be significantly influenced by well design and sampling techniques. Many of these influences can be attributed to hydrogeologic complexities, which can have notable variations on a fairly local scale. To adequately address these complexities, a site‐specific characterization of the hydrogeology is necessary. This is particularly important for specifying well construction details of monitoring wells for a ground‐water quality monitoring program.Data collected during the bailing of deep aquifer wells on Federal Prototype Oil Shale Lease Tract C‐a indicates the need for consistent and representative sample collection depths. Appreciable changes in water quality can be induced by variations in sample collection depths. In addition, unrepresentative data can be obtained due to the incorrect selection of intervals to be sampled in the well. Care must be taken to sample consistently from the same depth and aquifer interval during each and every sampling effort.Studies such as these provide necessary background information for developing ground‐water monitoring guidelines in the oil shale region. Sampling procedures must be consistent to assure representative data collection. In addition, wells should be designed and completed according to the local hydrogeology and the specific goals of the monitoring

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02748.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACTSlug and bailer tests are being used increasingly to evaluate the hydraulic properties of “tight” geologic units. Although these pulse methods of stressing a system are used typically only on single wells, the repeated pulse method described here stresses the system in the same manner, but the response is measured in observation wells. This type of pulse test yields much the same information as conventional pumping tests, but it is easier to perform in very low permeability units.The observation well response hydrographs are analyzed by curve‐matching techniques. In general, a unique set of type curves must be computed for each pulse test. These type curves are computed easily if the pulsed well is treated as a line‐source (or sink). The accuracy of the value of transmissivity (T) determined from the line‐source type curves compared to using the finite‐diameter well solution depends both on the pulsed well radius (rc) and the time interval between pulses (Δt). If TΔt/rc2is maintained greater than 50, then T determined from the line‐source solution will be within 25% of that determined from more accurate, but computationally inconvenient, finite‐diameter well type curves.The repeated‐pulse test technique was applied to an experimental well array completed in the Conasauga Shale Formation at Oak Ridge National Laboratory. Values of transmissivity determined by the repeated‐pulse method agreed well with the results of slug tests performed on each well individually, and in addition, provided information on storage coefficients and a

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1982.tb02749.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY