Wen-Sheng Lin - Academia.edu (original) (raw)

Papers by Wen-Sheng Lin

Research paper thumbnail of Influences of specific ions in groundwater on concrete degradation in subsurface engineered barrier system

SpringerPlus, 2016

The engineered barriers system (EBS) is an integral part of the radioactive waste disposal facili... more The engineered barriers system (EBS) is an integral part of the radioactive waste disposal facility. The EBS represents the manmade, engineered materials of a repository, including the waste form, waste canisters, concrete barrier, buffer materials, backfill, and seals, and can be used as physical and/or chemical obstructions to prevent or hinder the migration of radionuclides (Dupray and Laloui 2014; IAEA 2001a). The function of the EBS is to prevent and/or hinder the release of radionuclides from the waste to host rock and biosphere. However, the lack of an appropriate EBS design in the concrete barrier, backfill, and the selection of sealing and covering materials for trenches, vaults, and ditches may result in the ingress of groundwater and the release of radionuclides from the disposed wastes (IAEA 1999, 2001a, b).

Research paper thumbnail of Using a Mass Balance Model to Evaluate Groundwater Budget of Seawater-Intruded Island Aquifers1

JAWRA Journal of the American Water Resources Association, 2012

ABSTRACT Jang, Cheng‐Shin, Chen‐Wuing Liu, Shih‐Kai Chen, and Wen‐Sheng Lin, 2011. Using a Mass B... more ABSTRACT Jang, Cheng‐Shin, Chen‐Wuing Liu, Shih‐Kai Chen, and Wen‐Sheng Lin, 2011. Using a Mass Balance Model to Evaluate Groundwater Budget of Seawater‐Intruded Island Aquifers. Journal of the American Water Resources Association (JAWRA) 48(1): 61‐73. DOI: 10.1111/j.1752‐1688.2011.00593.xAbstract: The study developed a mass balance model to evaluate the groundwater budget of seawater‐intruded island aquifers using limited available data. The Penghu islands were selected as a study area. As sparse observed data were available in the islands, methods of combining water and chloride balances were used to determine the amounts of groundwater pumping, seawater intrusion, aquifer storages, and safe yields in the shallow and deep aquifers. The groundwater budget shows that seawater intrusion to freshwater aquifers was 1.38 × 106 and 0.29 × 106 m3/year in the shallow and deep aquifers, respectively, indicating that the seawater intrusion is severe in the both aquifers. The safe yield of the shallow aquifer was 14.56 × 106 m3/year in 2005 which was four times higher than that of the deep aquifer (3.70 × 106 m3/year). However, the annual pumping amounts in the shallow and deep aquifers were 4.77 × 106 and 3.63 × 106 m3/year, respectively. Although the safe yield of the shallow aquifer is enough for all water resources demands, only 55% of exploitation amount was extracted from the shallow aquifer due to its poor water quality. Groundwater exploitation in the deep aquifer should be significantly reduced and regulated by a dynamic management of pumping scheme because the annual pumping amounts are close to the safe yield and seawater intrusion occurs continually. Additionally, to alleviate further aquifer salination, at least half of the current annual groundwater abstraction should be reduced.

Research paper thumbnail of Stream filtration induced by pumping in a confined, unconfined or leaky aquifer bounded by two parallel streams or by a stream and an impervious stratum

Journal of Hydrology, 2014

ABSTRACT A mathematical model is developed for describing three-dimensional groundwater flow indu... more ABSTRACT A mathematical model is developed for describing three-dimensional groundwater flow induced by a fully-penetrating vertical well in aquifers between two parallel streams. A general equation is adopted to represent the top boundary condition which is applicable to either a confined, unconfined or leaky aquifer. The Robin (third-type) boundary condition is employed to represent the low-permeability streambeds. The Laplace-domain head solution of the model is derived by the double-integral and Laplace transforms. The Laplace-domain solution for a stream depletion rate (SDR ) describing filtration from the streams is developed based on Darcy’s law and the head solution and inverted to the time-domain result by the Crump method. In addition, the time-domain solution of SDR for the confined aquifer is developed analytically after taking the inverse Laplace transform and the time-domain solutions of SDR for the leaky and unconfined aquifers are developed using the Padé approximation. Both approximate solutions of SDR are expressed in terms of simple series and give fairly good match with the Laplace-domain SDR solution and measured data from a field experiment in New Zealand. The uncertainties in SDR predictions for the aquifers are assessed by performing the sensitivity analysis and Monte Carlo simulation. With the aid of the time-domain solutions, we have found that the effect of the vertical groundwater flow on the temporal SDR for a leaky aquifer is dominated by two lumped parameters: κ=Kvx02/(KhD2) and κ ′ = K ′D /(B ′Kv ) where D is the aquifer thickness, x 0 is a distance between the well and nearer stream, Kh and Kv are the aquifer horizontal and vertical hydraulic conductivities, respectively, and K ′ and B ′ are the aquitard hydraulic conductivity and thickness, respectively. When κ < 10, neglecting the vertical flow underestimates the SDR . When κ⩾10κ⩾10, the effect of vertical flow is negligible. When κ′⩽10-4κ′⩽10-4, the aquitard can be regarded as impermeable, and the leaky aquifer behaves as a confined one.

Research paper thumbnail of Multivariate approaches optimize locations of groundwater pumping facilities for different hydrogeological scales

Hydrological Processes, 2012

Research paper thumbnail of Estimation of land subsidence caused by loss of smectite-interlayer water in shallow aquifer systems

Hydrogeology Journal, 2006

Traditionally, land subsidence that results from groundwater over-pumping has often been describe... more Traditionally, land subsidence that results from groundwater over-pumping has often been described by the theory of consolidation. The mechanism of land subsidence due to the dehydration of clay minerals is not well addressed. A model of the “hydration state of smectite”, and a “solid solution model of smectite dehydration”, incorporating a thermodynamic solid solution model and laboratory results concerning clay-water systems of swelling pressure, hydration state and basal spacing in smectite interlayer, are employed to examine the effect of the release of water from the smectite interlayer on land subsidence in the coastal area of the Chou-Shui River alluvial fan and the Yun Lin offshore industrial infrastructure complex in Taiwan. The results indicate that 9.56–22.80% of the total cumulative land subsidence to a depth of 300 m is consistent with smectite dehydration following the over-pumping of groundwater. This dehydration-related land subsidence occurred to a depth of 0–60 m, with subsidence due to smectite dehydration accounting for 6.20–13.32% of the primary consolidation. Additionally, the total amount of subsidence resulting from both smectite dehydration and primary consolidation is consistent with the subsidence observed in the field. This study reveals that smectite dehydration appears to be important in assessing and predicting land subsidence in shallow aquifer systems.

Research paper thumbnail of A Smectite Dehydration Model in a Shallow Sedimentary Basin: Model Development

clays and clay minerals, 2005

Research paper thumbnail of A simulation of the supergene copper enrichment process

A simplified simulation of copper precipitation during supergene enrichment processes was carried... more A simplified simulation of copper precipitation during supergene enrichment processes was carried out to study the feedback behaviors of geochemical reaction and groundwater flow. Reevaluation of the pattern of formation was studied by means of the HYDROGEOCHEM code, wherein redox half reactions of covellite and chalcocite as reactants as well as precipitation reactions to form covellite and chalcocite were considered.

Research paper thumbnail of The Effect of Porosity Change in Bentonite Caused by Decay Heat on Radionuclide Transport through Buffer Material

Applied Sciences

Bentonite is used as a buffer material in most high-level radioactive waste (HLW) repository desi... more Bentonite is used as a buffer material in most high-level radioactive waste (HLW) repository designs. Smectite clay is the main mineral component of bentonite and plays a key role in controlling the buffer’s physical and chemical behaviors. Moreover, the long-term functions of buffer clay could be lost through smectite dehydration under the prevailing temperature stemming from the heat of waste decay. Therefore, the influence of waste decay temperatures on bentonite performance needs to be studied. However, seldom addressed is the influence of the thermo-hydro-chemical (T-H-C) processes on buffer material degradation in the engineered barrier system (EBS) of HLW disposal repositories as related to smectite clay dehydration. Therefore, we adopted the chemical kinetic model of smectite dehydration to calculate the amount of water expelled from smectite clay minerals caused by the higher temperatures of waste decay heat. We determined that the temperature peak of about 91.3 °C occurred...

Research paper thumbnail of Influences of specific ions in groundwater on concrete degradation in subsurface engineered barrier system

SpringerPlus, 2016

The engineered barriers system (EBS) is an integral part of the radioactive waste disposal facili... more The engineered barriers system (EBS) is an integral part of the radioactive waste disposal facility. The EBS represents the manmade, engineered materials of a repository, including the waste form, waste canisters, concrete barrier, buffer materials, backfill, and seals, and can be used as physical and/or chemical obstructions to prevent or hinder the migration of radionuclides (Dupray and Laloui 2014; IAEA 2001a). The function of the EBS is to prevent and/or hinder the release of radionuclides from the waste to host rock and biosphere. However, the lack of an appropriate EBS design in the concrete barrier, backfill, and the selection of sealing and covering materials for trenches, vaults, and ditches may result in the ingress of groundwater and the release of radionuclides from the disposed wastes (IAEA 1999, 2001a, b).

Research paper thumbnail of Using a Mass Balance Model to Evaluate Groundwater Budget of Seawater-Intruded Island Aquifers1

JAWRA Journal of the American Water Resources Association, 2012

ABSTRACT Jang, Cheng‐Shin, Chen‐Wuing Liu, Shih‐Kai Chen, and Wen‐Sheng Lin, 2011. Using a Mass B... more ABSTRACT Jang, Cheng‐Shin, Chen‐Wuing Liu, Shih‐Kai Chen, and Wen‐Sheng Lin, 2011. Using a Mass Balance Model to Evaluate Groundwater Budget of Seawater‐Intruded Island Aquifers. Journal of the American Water Resources Association (JAWRA) 48(1): 61‐73. DOI: 10.1111/j.1752‐1688.2011.00593.xAbstract: The study developed a mass balance model to evaluate the groundwater budget of seawater‐intruded island aquifers using limited available data. The Penghu islands were selected as a study area. As sparse observed data were available in the islands, methods of combining water and chloride balances were used to determine the amounts of groundwater pumping, seawater intrusion, aquifer storages, and safe yields in the shallow and deep aquifers. The groundwater budget shows that seawater intrusion to freshwater aquifers was 1.38 × 106 and 0.29 × 106 m3/year in the shallow and deep aquifers, respectively, indicating that the seawater intrusion is severe in the both aquifers. The safe yield of the shallow aquifer was 14.56 × 106 m3/year in 2005 which was four times higher than that of the deep aquifer (3.70 × 106 m3/year). However, the annual pumping amounts in the shallow and deep aquifers were 4.77 × 106 and 3.63 × 106 m3/year, respectively. Although the safe yield of the shallow aquifer is enough for all water resources demands, only 55% of exploitation amount was extracted from the shallow aquifer due to its poor water quality. Groundwater exploitation in the deep aquifer should be significantly reduced and regulated by a dynamic management of pumping scheme because the annual pumping amounts are close to the safe yield and seawater intrusion occurs continually. Additionally, to alleviate further aquifer salination, at least half of the current annual groundwater abstraction should be reduced.

Research paper thumbnail of Stream filtration induced by pumping in a confined, unconfined or leaky aquifer bounded by two parallel streams or by a stream and an impervious stratum

Journal of Hydrology, 2014

ABSTRACT A mathematical model is developed for describing three-dimensional groundwater flow indu... more ABSTRACT A mathematical model is developed for describing three-dimensional groundwater flow induced by a fully-penetrating vertical well in aquifers between two parallel streams. A general equation is adopted to represent the top boundary condition which is applicable to either a confined, unconfined or leaky aquifer. The Robin (third-type) boundary condition is employed to represent the low-permeability streambeds. The Laplace-domain head solution of the model is derived by the double-integral and Laplace transforms. The Laplace-domain solution for a stream depletion rate (SDR ) describing filtration from the streams is developed based on Darcy’s law and the head solution and inverted to the time-domain result by the Crump method. In addition, the time-domain solution of SDR for the confined aquifer is developed analytically after taking the inverse Laplace transform and the time-domain solutions of SDR for the leaky and unconfined aquifers are developed using the Padé approximation. Both approximate solutions of SDR are expressed in terms of simple series and give fairly good match with the Laplace-domain SDR solution and measured data from a field experiment in New Zealand. The uncertainties in SDR predictions for the aquifers are assessed by performing the sensitivity analysis and Monte Carlo simulation. With the aid of the time-domain solutions, we have found that the effect of the vertical groundwater flow on the temporal SDR for a leaky aquifer is dominated by two lumped parameters: κ=Kvx02/(KhD2) and κ ′ = K ′D /(B ′Kv ) where D is the aquifer thickness, x 0 is a distance between the well and nearer stream, Kh and Kv are the aquifer horizontal and vertical hydraulic conductivities, respectively, and K ′ and B ′ are the aquitard hydraulic conductivity and thickness, respectively. When κ < 10, neglecting the vertical flow underestimates the SDR . When κ⩾10κ⩾10, the effect of vertical flow is negligible. When κ′⩽10-4κ′⩽10-4, the aquitard can be regarded as impermeable, and the leaky aquifer behaves as a confined one.

Research paper thumbnail of Multivariate approaches optimize locations of groundwater pumping facilities for different hydrogeological scales

Hydrological Processes, 2012

Research paper thumbnail of Estimation of land subsidence caused by loss of smectite-interlayer water in shallow aquifer systems

Hydrogeology Journal, 2006

Traditionally, land subsidence that results from groundwater over-pumping has often been describe... more Traditionally, land subsidence that results from groundwater over-pumping has often been described by the theory of consolidation. The mechanism of land subsidence due to the dehydration of clay minerals is not well addressed. A model of the “hydration state of smectite”, and a “solid solution model of smectite dehydration”, incorporating a thermodynamic solid solution model and laboratory results concerning clay-water systems of swelling pressure, hydration state and basal spacing in smectite interlayer, are employed to examine the effect of the release of water from the smectite interlayer on land subsidence in the coastal area of the Chou-Shui River alluvial fan and the Yun Lin offshore industrial infrastructure complex in Taiwan. The results indicate that 9.56–22.80% of the total cumulative land subsidence to a depth of 300 m is consistent with smectite dehydration following the over-pumping of groundwater. This dehydration-related land subsidence occurred to a depth of 0–60 m, with subsidence due to smectite dehydration accounting for 6.20–13.32% of the primary consolidation. Additionally, the total amount of subsidence resulting from both smectite dehydration and primary consolidation is consistent with the subsidence observed in the field. This study reveals that smectite dehydration appears to be important in assessing and predicting land subsidence in shallow aquifer systems.

Research paper thumbnail of A Smectite Dehydration Model in a Shallow Sedimentary Basin: Model Development

clays and clay minerals, 2005

Research paper thumbnail of A simulation of the supergene copper enrichment process

A simplified simulation of copper precipitation during supergene enrichment processes was carried... more A simplified simulation of copper precipitation during supergene enrichment processes was carried out to study the feedback behaviors of geochemical reaction and groundwater flow. Reevaluation of the pattern of formation was studied by means of the HYDROGEOCHEM code, wherein redox half reactions of covellite and chalcocite as reactants as well as precipitation reactions to form covellite and chalcocite were considered.

Research paper thumbnail of The Effect of Porosity Change in Bentonite Caused by Decay Heat on Radionuclide Transport through Buffer Material

Applied Sciences

Bentonite is used as a buffer material in most high-level radioactive waste (HLW) repository desi... more Bentonite is used as a buffer material in most high-level radioactive waste (HLW) repository designs. Smectite clay is the main mineral component of bentonite and plays a key role in controlling the buffer’s physical and chemical behaviors. Moreover, the long-term functions of buffer clay could be lost through smectite dehydration under the prevailing temperature stemming from the heat of waste decay. Therefore, the influence of waste decay temperatures on bentonite performance needs to be studied. However, seldom addressed is the influence of the thermo-hydro-chemical (T-H-C) processes on buffer material degradation in the engineered barrier system (EBS) of HLW disposal repositories as related to smectite clay dehydration. Therefore, we adopted the chemical kinetic model of smectite dehydration to calculate the amount of water expelled from smectite clay minerals caused by the higher temperatures of waste decay heat. We determined that the temperature peak of about 91.3 °C occurred...