共查询到20条相似文献,搜索用时 15 毫秒
1.
The feasibility of compacted sewage sludge serving as a barrier for tailing impoundment was evaluated by the batch test and
hydraulic conductivity test with respect to heavy metal retardation and impermeability. The batch test results showed that
the effective removal of heavy metals approached 97.8 and 93.4% for Zn and Cd, respectively. Formation of precipitation of
oxy(hydroxide) and carbonate minerals was mainly responsible for the attenuation of heavy metals in the early period of the
test. Nevertheless, the further removal of heavy metals can be attributed to the sulfate reduction. The hydraulic conductivity
test indicated that almost all of the heavy metals contained in simulated acid pore water were retarded by compacted sewage
sludge. The hydraulic conductivity of the compacted sewage sludge ranged from 3.0 × 10 −8 to 8.0 × 10 −8 cm s −1, lower than 1.0 × 10 −7 cm s −1, which is required by regulations for the hydraulic barrier in landfill sites. Thus, this study suggested that compacted
sewage sludge could be used as a bottom barrier for tailing impoundment. 相似文献
2.
Flexible-wall hydraulic conductivity tests were carried out on bottom ash, fly ash and compacted specimens of sand with additions
of 0, 3, 6, 9 and 18% of bentonite. In order to study the effect of bentonite inclusion and particle morphology on the hydraulic
conductivity of the admixtures, an investigation was undertaken based on thin section micrographs. It was found that, for
both bottom and fly ash admixtures, bentonite addition reduced only one order of magnitude the hydraulic conductivity, from
1.78 × 10 −6 m/s to 1.39 × 10 −7 m/s. On the other hand, the sand hydraulic conductivity was reduced five orders of magnitude, from 3.17 × 10 −5 m/s to 5.15 × 10 −10 m/s. Among several factors that can be responsible for the difficulty in reducing hydraulic conductivity, such as ash grain
size distribution and elevated cation concentration (leached from the ash) in pore water, it can also be recalled the high
particle voids observed in the ash by means of microscopic analysis. The same is not true with the sand, which has solid particles,
without inner voids. 相似文献
3.
A multi-layered aquifer, typical of riverbank alluvial deposits in Korea, was studied to determine the hydrologic properties.
The geologic logging showed that the subsurface of the study site was comprised of four distinctive hydrogeologic units: silt,
sand, highly weathered and fresh bedrock layers. The electrical resistivity survey supplied information on lateral extension
of hydrogeologic strata only partially identified by a limited number of the geologic loggings. The laboratory column tracer
test for the recovered core of the sand layer resulted in a hydraulic conductivity of 5.00×10 −2 cm/s. The slug tests performed in the weathered rock layer yielded hydraulic conductivities of 4.32–7.72×10 −4 cm/s. Hydraulic conductivities for the sand layer calculated from the breakthrough curves of bromide ranged between 2.08×10 −3 and 2.44×10 −2 cm/s with a geometric mean of 6.89×10 −3 cm/s, which is 7 times smaller than that from the laboratory column experiment. The trend of increasing hydraulic conductivity
with an increase in tracer travel length is likely a result of the increased likelihood of encountering a high conductivity
zone as more of the aquifer is tested. The combined hydrogeologic site characterization using hydraulic tests, tracer tests,
and column test with geologic loggings and geophysical survey greatly enhanced the understanding of the hydrologic properties
of the multi-layered alluvial aquifer. 相似文献
4.
Vertical barrier walls are often constructed to prevent contamination of ground water and soils by landfill leachate. The
leachate water levels in landfills in southern China are generally high. Contaminants in such landfills may migrate through
the vertical barrier walls and give rise to environmental problems. Qizishan landfill in Suzhou, China was taken as an example
to investigate contaminant migration through the vertical barrier walls. Advection, diffusive and adsorption processes were
considered in the analysis. Influences of permeability and depth of the barrier wall on contaminant migration were analyzed.
The results show that it will be 13.5 years before breakthrough at 0.1% of the source concentration and 20.5 years before
breakthrough at 10% of the source concentration. By and large, the contaminant has not passed through the barrier wall at
present, and the contaminated zone is mainly located in the sandy clay layer near the earth dam, which is validated by testing
on sampled soils. Hydraulic conductivity and depth of the barrier wall are critical to contaminant migration. Special attention
need to be paid on them when building such a barrier wall. If bottom of the barrier wall is keyed into the aquitard and the
hydraulic conductivity reaches 10 −9 m/s, the time before breakthrough will be long enough to allow stabilization of the landfill. Pollution of the surroundings
will be avoided, and therefore the requirement for contaminant control will be attained. 相似文献
5.
A methodology to estimate a methane emission in a waste landfill site was developed. The methane flux at a waste landfill
site in summer, autumn, and winter was within the following ranges: from −1.3×10 −2 to 16, from −6.4×10 −2 to 7.5, and from −1.6×10 −3 to 1.5×10 −2 g-CH 4 m −2 h −1, respectively. In those seasons, the mean methane emission rate and coefficient of variation were 1.1 g-CH 4 m −2 h −1 ±290%, 0.57 g-CH 4 m −2 h −1 ±347%, and 5.4×10 −2 g-CH 4 m −2 h −1 ±370%, respectively. These results simultaneously showed that fluctuations of methane emission from the landfill surface
were both of spatial and temporal variability. In each season, an exponential relationship was observed between the methane
flux density and the ground temperature. Total methane emissions were estimated to be 5.7×10 −2, 7.1×10 −3, and 1.7×10 −3 g-CH 4 m −2 h −1 in the summer, autumn, and winter surveys, respectively, using a temperature surrogated-kriging method. The results of this
study would improve upon the labor-intensive closed-chamber method, and could be a more practical way to estimate methane
emissions from waste landfills. 相似文献
6.
Compositional depth profiles in the leached layer of feldspar surfaces are usually interpreted by using analytical solutions
which introduce oversimplifying assumptions. Here we present a general multicomponent interdiffusion numerical model for simulating
cation release from a preferentially leached layer on feldspar surfaces in acid solutions. The numerical model takes into
account interdiffusion, dissolution of the solid phase (represented by a moving boundary problem), and adsorption in the leached
layer. Effective diffusion coefficients of ions vary with concentration along the leached layer. Governing equations of ions
diffusion in the leached layer are solved numerically with a finite element method implemented in a multicomponent reactive
transport code, CORE 3D, previously verified against analytical solutions of compositional depth profiles. The numerical model is tested with published
X-ray photoelectron spectroscopy (XPS) data on early development of compositional profiles of labradorite leached in pH 2
HCl solutions. Model parameters are estimated by fitting depth profiles of Ca and Al measured at 12, 26, 48, 72, and 143 h.
The best fit is achieved with tracer diffusion coefficients of 4 × 10 −18, 8 × 10 −17, 3.4 × 10 −17, and 7 × 10 −18 cm 2/s for H, Na, Ca, and Al, respectively, which fall within the range of values reported in the literature. Our estimate of
the retreat velocity corresponding to the dissolution rate is 3 × 10 −13 cm/s. Results of sensitivity runs show that computed compositional profiles are sensitive to most model parameters. 相似文献
7.
Physical and hydraulic properties of sediment from two karst aquifers were measured to determine (1) the similarity of sediment
between karst aquifer systems and (2) the importance of sediment in modeling flow through karst aquifers. The sediment from
the two systems was similar in size and composition. Within both aquifers, the silt-sized sediment was composed primarily
of quartz, with minor amounts of plagioclase and clays. Hydraulic conductivity of the sediment measured directly (falling-head
test) ranged from 1.61×10 −7 to 1.33×10 −6 m s –1 and estimated using the Campbell equation ranged from 8.30×10 −8 to 8.98×10 −7 m s –1. These values of hydraulic conductivity fall within the span of hydraulic conductivities for carbonate rocks, indicating
that the sediment and carbonate matrix could be represented as one mathematical unit in modeling flow through karst aquifers.
Statistical agreement in the hydraulic conductivity values generated by the two methods indicates that the estimation technique
could be used to calculate hydraulic conductivities; thus allowing karst scientist to collect bulk sediment samples instead
of having to collect cores from within karst aquifers.
Electronic Publication 相似文献
8.
The thermal expansion of gehlenite, Ca 2Al[AlSiO 7], (up to T=830 K), TbCaAl[Al 2O 7] (up to T=1100 K) and SmCaAl[Al 2O 7] (up to T=1024 K) has been determined. All compounds are of the melilite structure type with space group
Thermal expansion data were obtained from in situ X-ray powder diffraction experiments in-house and at HASYLAB at the Deutsches
Elektronen Synchrotron (DESY) in Hamburg (Germany). The thermal expansion coefficients for gehlenite were found to be: α 1=7.2(4)×10 −6×K −1+3.6(7)×10 −9Δ T×K −2 and α 3=15.0(1)×10 −6×K −1. For TbCaAl[Al 2O 7] the respective values are: α 1=7.0(2)×10 −6×K −1+2.0(2)×10 −9Δ T×K −2 and α 3=8.5(2)×10 −6×K −1+2.0(3)×10 −9Δ T×K −2, and the thermal expansion coefficients for SmCaAl[Al 2O 7] are: α 1=6.9(2)×10 −6×K −1+1.7(2)×10 −9Δ T×K −2 and α 3=9.344(5)×10 −6×K −1. The expansion mechanisms of the three compounds are explained in terms of structural trends obtained from Rietveld refinements
of the crystal structures of the compounds against the powder diffraction patterns. No structural phase transitions have been
observed. While gehlenite behaves like a ‘proper’ layer structure, the aluminates show increased framework structure behavior.
This is most probably explained by stronger coulombic interactions between the tetrahedral conformation and the layer-bridging
cations due to the coupled substitution (Ca 2++Si 4+)–( Ln
3++Al 3+) in the melilite-type structure.
This article has been mistakenly published twice. The first and original version of it is available at . 相似文献
9.
Compacted soil–bentonite liners, consisting of a sandy soil mixed with bentonite as backfill, are used extensively as engineered barriers for contaminant containment. This paper studies the valorization of local materials containing calcareous sand, tuff obtained from Laghouat region (in the South Algeria), to associate with bentonite in order to improve their hydraulic characteristics for use as landfill liner material. Firstly, a geotechnical characterization of mixtures chooses from a fixed percentage to 10% bentonite and different percentages of calcareous sand and tuff so that they are complementary to 90% by not 10%. Thereafter, the determination of saturated hydraulic conductivity at falling-head permeability (K v) and oedometer (K id, indirect Measure) tests of all compacted mixtures at Optimum Normal Proctor have been carried out using both permeates by tap water and a landfill leachate in order to simulate long-term conditions. The results showed that the saturated hydraulic conductivity of tap water is relatively lower than the one saturated by leachate in the falling-head test, unlike the oedometer test. The B 10CS 20T 70 mixture has satisfied the hydraulic conductivity criterion of bottom barriers (i.e. water permeated: k v20° = 1.97 × 10 ?9 and k id from 7 × 10 ?9 to 1.83 × 10 ?10 < 10 ?9m/s; leachate permeated: k v20° = 2.91 × 10 ?9 and k id from 7 × 10 ?9 at 1.44 × 10 ?10 < 10 ?9 m/s). Finally, a comparison between direct measurements of the saturated hydraulic conductivity by triaxial (K d) test and oedometer test (K id) in the range of effective stress applied 100–800 kPa led to propose equations of correlations between these two methods. In conclusion, adopted formulation B 10CS 20T 70 perfectly meets the regulatory requirements in force and constitutes an economic product based on available local materials for engineers barriers. 相似文献
10.
A 52-yr record of dissolved oxygen in Chesapeake Bay (1950–2001) and a record of nitrate (NO 3
−) loading by the Susquehanna River spanning a longer period (1903, 1945–2001) were assembled to describe the long-term pattern
of hypoxia and anoxia in Chesapeake Bay and its relationship to NO 3
− loading. The effect of freshwater inflow on NO 3
− loading and hypoxia was also examined to characterize its effect at internannual and longer time scales. Year to year variability
in river flow accounted for some of the observed changes in hypoxic volume, but the long-term increase was not due to increased
river flow. From 1950–2001, the volume of hypoxic water in mid summer increased substantially and at an accelerating rate.
Predicted anoxic volume (DO<0.2 mg I −1) at average river flow increased from zero in 1950 to 3.6×10 9 m 3 in 2001. Severe hypoxia (DO<1.0 mg I −1) increased from 1.6×10 9 to 6.5×10 9 m 3 over the same period, while mild hypoxia (DO<2.0 mg I −1) increased from 3.4×10 9 to 9.2×10 9 m 3. NO 3
− concentrations in the Susquehanna River at Harrisburg, Pennsylvania, increased up to 3-fold from 1945 to a 1989 maximum and
declined through 2001. On a decadal average basis, the superposition of changes in river flow on the long-term increase in
NO 3
− resulted in a 2-fold increase in NO 3
− loading from the Susquehanna River during the 1960s to 1970s. Decadal average loads were subsequently stable through the
1990s. Hypoxia was positively correlated with NO 3
− loading, but more extensive hypoxia was observed in recent years than would be expected from the observed relationship. The
results suggested that the Bay may have become more susceptible to NO 3
− loading. To eliminate or greatly reduce anoxia will require reducing average annual total nitrogen loading to the Maryland
mainstem Bay to 50×10 6 kg yr −1, a reduction of 40% from recent levels. 相似文献
11.
A fundamental mechanism on the atomic level for self-diffusion in the proton layer of portlandite, Ca(OH) 2, was investigated by conducting hydrogen–deuterium (H–D) exchange diffusion experiments and by deriving potential energy
curves of OH vibrations from optical absorption measurements. Synthetic single crystals of portlandite were used in H–D experiments
between 250 and 450°C at 150 MPa. Arrhenius parameters for proton diffusion perpendicular to the c-axis gave a frequency factor of 1.0 × 10 −10 m 2/s and activation energy of 0.61 eV (58.5 kJ/mol). The activation energy corresponds to the height of the potential barrier
between two oxygen atoms across an interlayer. The potential barrier height was also theoretically estimated using the OH
potential energy curve (OH-PEC) determined by optical absorption measurements. Experimental and theoretical results suggest
that the potential barrier height cannot be simply determined by overlapping two OH-PECs. The potential barrier derived theoretically
was 3.11 eV. This is too high for the activation energy of the proton diffusion. It implies that the interaction between a
diffusing proton and the vacancy of a proton site, and the shortening of interlayer oxygen distance by thermal vibration reduce
the potential barrier. 相似文献
12.
Tens of thousands of municipal solid waste (MSW) landfill sites worldwide hold a high risk of contaminating groundwater. This study aimed to establish a practical hydrogeological classification system for MSW landfill sites and explores the correlation between the classification and the risk of groundwater contamination. Hydrogeological information and groundwater contamination data from 80 MSW landfill sites in China were collected and analyzed, and a general hydrogeological model was proposed. The key hydrogeological parameters in the model were identified and analyzed, including the relative depth to the water table, the ratio of the length of the MSW site’s recharge boundary to the combined length of the discharge boundary and hydrobalance boundary, the hydraulic conductivity of the bearing layer, and the background hydraulic gradient. On the basis of the general model, hydrogeological conditions at the landfill sites were categorized into seven subtypes. By using chloride, ammoniacal nitrogen and chemical oxygen demand as the characteristic contaminants, the migration features of groundwater contaminants within the seven subtypes of landfill sites were revealed. It was found that the maximum contaminant migration distance could be 2,000 and 300 m at the landfill sites with ‘plain and intensive runoff’ type and ‘valley and weak runoff’ type, respectively, and the corresponding concentration gradients of the characteristic contaminants were less than 10 mg/(L × m) and greater than 10 mg/(L × m). This work provides a guide for implementing cost-effective site investigation and environmental risk management at landfill sites with different types of hydrogeological conditions. 相似文献
13.
Kinmen Island is a small, tectonically stable, granitic island that has been suffering from a scarcity of fresh water resources
due to excessive annual evapotranspiration over annual precipitation. Recent studies further indicate that shallow (0–70 m)
sedimentary aquifers, the major sources of groundwater supply, have already been over-exploited. Therefore, this preliminary
study is to investigate the existence of exploitable water resources that can balance the shortage of fresh water on this
island. Site characterization data are obtained from island-wide geophysical surveys as well as small-scale tests performed
in a study area formed by three deep (maximum depth to 560 m) vertical boreholes installed in mid-east Kinmen northeast to
Taiwu Mountain. Vertical fracture frequency data indicate that the rock body is fractured with a spatially correlated pattern,
from which three major fracture zones (depths 0–70, 330–360, and below 450 m) can be identified. Geologic investigations indicate
that the deepest fracture zone is caused by the large-scale, steeply dipping Taiwushan fault. This fault may have caused a
laterally extensive low-resistivity zone, a potential fractured aquifer, near Taiwu Mountain. The middle fracture zone is
induced by the Taiwushan fault and intersects the fault approximately 21 m southeast of the study area below a depth of 350 m.
Slug testing results yield fracture transmissivity varying from 4.8 × 10 −7 to 2.2 × 10 −4 m 2/s. Cross-hole tests have confirmed that hydraulic connectivity of the deeper rock body is controlled by the Taiwushan fault
and the middle fracture zone. This connectivity may extend vertically to the sedimentary aquifers through high-angle joint
sets. Despite the presence of a flow barrier formed by doleritic dike at about 300 m depth, the existence of fresh as well
as meteoric water in the deeper rock body manifests that certain flow paths must exist through which the deeper fractured
aquifers can be connected to the upper rock body. Therefore, groundwater stored within the Taiwushan fault and the associated
low-resistivity zone can be considered as additional fresh water resources for future exploitation. 相似文献
14.
Magnetic properties and heavy metal content of landfill leachate sludge samples from two municipal solid waste disposal sites
near Bandung, West Java, Indonesia, and their correlation with heavy metals are studied in the present work. Leachate was
found to be sufficiently magnetic with mass-specific magnetic susceptibility that varies from 64.8 to 349.0 × 10 −8 m 3 kg −1. It is, however, less magnetic than the soils around the landfill sites. The magnetic minerals are predominantly pseudo-single
domain and multidomain magnetite. Leachate samples from the older but inactive disposal site, Jelekong, are found to be more
magnetic than that from Sarimukti, the younger and active site. The enhancement of leachate due to the soil-derived ferrimagnetic
particles is possibly the same for both Sarimukti and Jelekong. The fact that strong correlation between magnetic parameters
and heavy metals is observed in Jelekong but is absent in Sarimukti suggests that the use of magnetic measurement as a proxy
measurement for heavy metal content in leachate is plausible provided that the magnetic susceptibility exceeds certain threshold
value. Moreover, the accumulation of magnetic minerals and heavy metals in leachate might depend on the activity and the age
of landfill site. 相似文献
15.
The thermal expansion of gehlenite, Ca 2Al[AlSiO 7], (up to T=830 K), TbCaAl[Al 2O 7] (up to T=1,100 K) and SmCaAl[Al 2O 7] (up to T=1,024 K) has been determined. All compounds are of the melilite structure type with space group
Thermal expansion data was obtained from in situ X-ray powder diffraction experiments in-house and at HASYLAB at the Deutsches Elektronen Synchrotron (DESY) in Hamburg (Germany). The thermal expansion coefficients for gehlenite were found to be: α 1=7.2(4)×10 −6 K −1+3.6(7)×10 −9Δ T K −2 and α 3=15.0(1)×10 −6 K −1. For TbCaAl[Al 2O 7] the respective values are: α 1=7.0(2)×10 −6 K −1+2.0(2)×10 −9Δ T K −2 and α 3=8.5(2)×10 −6 K −1+2.0(3)×10 −9Δ T K −2, and the thermal expansion coefficients for SmCaAl[Al 2O 7] are: α 1=6.9(2)× 10 −6 K −1+1.7(2)×10 −9Δ T K −2 and α 3=9.344(5)×10 −6 K −1. The expansion-mechanisms of the three compounds are explained in terms of structural trends obtained from Rietveld refinements
of the crystal structures of the compounds against the powder diffraction patterns. No structural phase transitions have been
observed. While gehlenite behaves like a ’proper’ layer structure, the aluminates show increased framework structure behaviour.
This is most probably explained by stronger coulombic interactions between the tetrahedral conformation and the layer-bridging
cations due to the coupled substitution (Ca 2++Si 4+)-( Ln
3++Al 3+) in the melilite-type structure.
Electronic Supplementary Material Supplementary material is available for this article at 相似文献
16.
A long-term elution experiment to study the saturated transport of pre-accumulated fertilizers by-products, was conducted
within a large tank (4 × 8 × 1.4 m) equipped with 26 standard piezometers. Sandy sediments (35 m 3), used to fill the tank, were excavated from an unconfined alluvial aquifer near Ferrara (Northern Italy); the field site
was connected to a pit lake located in a former agricultural field. To evaluate spatial heterogeneity, the tank’s filling
material was characterized via slug tests and grain-size distribution analysis. The investigated sediments were characterized
by a large spectrum of textures and a heterogeneous hydraulic conductivity ( k) field. Initial tank pore water composition exhibited high concentration of nitrate (NO 3
−) sulfate (SO 4
2−) calcium (Ca 2+), and magnesium (Mg 2+), due to fertilizer leaching from the top soil in the field site. The initial spatial distribution of NO 3
− and SO 4
2− was heterogeneous and not related to the finer grain-size content (<63 μm). The tank’s material was flushed with purified
tap water for 800 days in steady-state conditions; out flowing water was regularly sampled to monitor the migration rate of
fertilizer by-products. Complete removal of NO 3
− and SO 4
2− took 500 and 600 days, respectively. Results emphasized organic substrate availability and spatial heterogeneities as the
most important constraints to denitrification and nitrogen removal, which increase the time required to achieve remediation
targets. Finally, the obtained clean-up time was compared with a previous column experiment filled with the same sediments. 相似文献
17.
An in situ synchrotron X-ray diffraction study was carried out on ε-FeOOH at room temperature up to a pressure of 8.6 GPa
using the energy-dispersive method. The linear compressibility was determined to be β
a
= 1.69(3) × 10 −3 GPa −1, β
b
= 2.86(6) × 10 −3 GPa −1, and β
c
= 1.73(5) × 10 −3 GPa −1. The b-axis of the unit cell is more compressible than the a and c axes. The pressure–volume data were fitted to a third-order Birch–Murnaghan equation of state. The best fit was found using
a room temperature isothermal bulk modulus of K
0 = 126(3) GPa and its pressure derivative K′ = 10(1). 相似文献
18.
A gabbro-diorite plutonic complex from the Southeast Obudu Plateau, representing limited volumes of magma, was studied for its trace and rare-earth element characteristics, in an attempt to document its genetic and geodynamic history. Geochemical studies indicate that the gabbro samples are characterized by variable concentrations and low averages of such index elements as Cr (40×10-6–200×10-6; av. 80×10-6), Ni (40×10-6–170×10-6; 53.33×10-6) and Zr (110×10-6–240×10-6; 116.67×10-6); variable and high average... 相似文献
19.
Rock and flow parameters of three karstic-fissured-porous aquifers in the Krakow-Silesian Triassic formations were measured
using various methods and compared. Though cavern and fissure porosities are shown to be very low (cavern porosity below 0.5%
and fracture porosity below 0.2%), they contribute dominantly to the hydraulic conductivity (from about 1.3×10 –6 to about 11×10 –6 m/s). Matrix porosity (2–11%) is shown to be the main water reservoir for solute transport and the main or significant contributor
to the specific yield (<2%). Though the matrix porosity is shown to be much larger than the sum of the cavern and fissure
porosities, its contribution to the total hydraulic conductivity is practically negligible (hydraulic conductivity of the
matrix is from about 5×10 –11 m/s to about 2×10 –8 m/s). On the other hand, the matrix porosity (for neglected cavern and fissure porosities) when combined with tracer ages
(or mean travel times) is shown to yield proper values of the hydraulic conductivity (K) by applying the following formula:
K≅(matrix porosity×mean travel distance)/(mean hydraulic gradient×mean tracer age). Confirming earlier findings of the authors,
this equation is shown to be of great practical importance because matrix porosity is easily measured in the laboratory on
rock samples, whereas cavern and fracture porosities usually remain unmeasurable.
Received: 21 February 1997 · Accepted: 13 May 1997 相似文献
20.
Within carbonate systems, the working hypothesis suggests that when a conduit is flooded fluid and solute migrate from the
conduit into the matrix. This flux of fluid and solute into the matrix creates a reservoir that can be slowly released once
the flooding recedes. Although hypothesized, these fluxes have never been measured. To quantify the distance that a fluid
and solute would move into a matrix, the fluxes of fluid and solute from a conduit into a matrix were simulated for nine different
carbonate aquifer systems. Two independent numerical approaches were used to simulate (1) fluid flux into the matrix and (2)
solute flux into the matrix during a flooding event. When flooding occurs within the conduit, the volume of water transported
into and stored in the matrix with a high porosity and high hydraulic conductivity (Floridan Aquifer) was less than 0.34 m 3 along a 1 m length of conduit, resulting in a penetration depth of 7.2×10 −2 m into the matrix. In a low porosity and low hydraulic conductivity matrix (Ozark Plateau), the volume of water transported
into and stored in the matrix was less than 6.85×10 −5 m 3 along a 1 m length of conduit, resulting in a penetration depth of 2.0×10 −4 m into the matrix. Simulated solute flow shows that less than 0.1% of the solute moves in to the matrix. The two approaches
demonstrate that during high flow conditions fluid and solute are forced through the conduits, with very little moving into
the carbonate matrix. Once the fluid and solute enter a conduit and are moving, they will remain in the conduit until they
are discharged at an outlet. Thus, a carbonate matrix does not become a reservoir for solute and fluid during a high-flow
event. 相似文献
|