Example: Akacievej - Revision history

Klmos: /* Example: Setup and application of models for a field site (Akacievej, Hedehusene) */

2019-07-05T09:57:39Z

‎Example: Setup and application of models for a field site (Akacievej, Hedehusene)

Klmos: /* Example: Setup and application of models for a field site (Akacievej, Hedehusene) */

2019-07-04T16:05:26Z

‎Example: Setup and application of models for a field site (Akacievej, Hedehusene)

Klmos at 08:38, 4 July 2019

2019-07-04T08:38:49Z

Klmos at 08:25, 4 July 2019

2019-07-04T08:25:02Z

Klmos: /* Example: Setup and application of models for a field site (Akacievej, Hedehusene) */

2019-07-04T08:07:13Z

‎Example: Setup and application of models for a field site (Akacievej, Hedehusene)

Klmos: Added sorption and crushed limestone

2019-07-03T15:26:19Z

Added sorption and crushed limestone

Klmos at 15:00, 3 July 2019

2019-07-03T15:00:00Z

Klmos at 14:44, 3 July 2019

2019-07-03T14:44:53Z

Klmos: Started to add a description of the coupled 3D-2D model

2019-07-03T14:44:21Z

Started to add a description of the coupled 3D-2D model

Klmos: typo

2019-04-10T15:30:26Z

typo

@@ Line 5: / Line 5: @@
 Numerical modeling was integrated in the planning of new field tests and in the update of the conceptual model of the contaminated site, starting from a simple model and adding complexity, when new field data was available.
-The field data included information on spill history, well data (location, screen depth etc.), distribution of the contaminant (multilevel sampling), geology and hydrogeology.
+The field data included information on spill history, hydraulic head data, well data (location, screen depth etc.), distribution of the contaminant (multilevel sampling), geology and hydrogeology.
 To describe the geology and fracture system, data from borehole logs, packer tests, optical televiewers and cores were combined with an analysis of local heterogeneities and data from analogue sites.
 A pumping and tracer test was conducted at the site to determine flow and transport parameters of the fractures and matrix and depth-specific contaminant sampling allowed to characterize the contaminant distribution in the aquifer.
@@ Line 12: / Line 12: @@
 * [[:Media:Pumping_and_tracer_test_report.pdf |Report about the pumping and tracer tests at Akacievej, Hedehusene (PDF)]]
-In 2018, the the hydraulic heads were measured in the plume area, which showed that the flow conditions were fairly constant.
+In 2018, the the hydraulic heads were again measured in the plume area, which showed that the flow conditions were fairly constant since the hydraulic head leveling campaign in spring 2015.
 The picture of the PCE distribution was updated by depth-specific measurements in the source- and plume area using a bladder pump.
 To reduce the numerical effort and to simulate the plume propagation on a larger scale, a 3D source-zone model coupled to a 2D plume-scale model was developed.
@@ Line 24: / Line 24: @@
 [[File:mapcoupled2D-3Dmodel.png|500px|thumb|Fig.2: Map of the coupled 3D source-zone model and 2D plume-scale model.]]
-Since the depth-discrete contaminant sampling showed that a great part of the PCE contamination is located in the crushed limestone (upper 3-5 m), the crushed limestone was included in the model setup as a separate layer with different proporties as the fractured limestone.
+Since the depth-discrete contaminant sampling showed that a great part of the PCE contamination is located in the crushed limestone (upper 3-5 m), the crushed limestone was included in the model setup as a separate layer with different properties as the fractured limestone.
 The bulk hydraulic conductivity was slightly lower than in the fractured limestone, and no distinct horizontal fractures as in the fractured limestone could be identified.
 Detailed investigations of the properties were very difficult for the crushed limestone, because due to its crushed state it is very unstable and core material was mostly lost.
-The characterization of the hydraulic properties was based on slug tests in wells that have a screen mostly in the crushed limestone and by evaluating the drawedown caused by the remediation pump installed at the Akacievej, which is also mostly located in the crushed limestone.
+The characterization of the hydraulic properties was based on slug tests in wells that have a screen mostly in the crushed limestone and by evaluating the drawdown caused by the remediation pump installed at the Akacievej, which is also mostly located in the crushed limestone.
 Most likely, the fractured limestone contains many more small fractures, small cavities and some larger intact limestone chunks.
-Then, most of the advective transport happens in the conductive areas with a diffusive exchange with lower conductive areas.
+Then, most of the advective transport happens in the conductive areas with a diffusive exchange with lower conductive (immobile) areas.
 This could be described by a dual-porosity model.
 However, there was only limited knowledge of the hydraulic properties in the high- and low-conductive areas and the exchange between them.
-Instead, a homogeneous unit with a unifrom conductivity was used.
+Instead, a homogeneous unit with a uniform conductivity was used.
-To still account for the immobile areas with storage of contaminant, the sorption coefficient was modified.
+To still account for the contaminant mass exchange with the immobile areas, the sorption coefficient was increased.
 <!--

@@ Line 5: / Line 5: @@
 Numerical modeling was integrated in the planning of new field tests and in the update of the conceptual model of the contaminated site, starting from a simple model and adding complexity, when new field data was available.
-The field data included information on spill history, distribution of the contaminant (multilevel sampling), geology and hydrogeology.
+The field data included information on spill history, well data (location, screen depth etc.), distribution of the contaminant (multilevel sampling), geology and hydrogeology.
 To describe the geology and fracture system, data from borehole logs, packer tests, optical televiewers and cores were combined with an analysis of local heterogeneities and data from analogue sites.
 A pumping and tracer test was conducted at the site to determine flow and transport parameters of the fractures and matrix and depth-specific contaminant sampling allowed to characterize the contaminant distribution in the aquifer.

@@ Line 1: / Line 1: @@
 == Example: Setup and application of models for a field site (Akacievej, Hedehusene) ==
 Several models were compared for the [[The Akacievej field site|'''Akacievej site''']], where a plume of dissolved PCE had spread in a fractured limestone aquifer and where a remediation system was in the process of re-evaluation.
-Numerical modeling was integrated in the planning of field tests and in the update of the conceptual model of the contaminated site, starting with a simple model and adding complexity, when new field data was available.
+Numerical modeling was integrated in the planning of new field tests and in the update of the conceptual model of the contaminated site, starting from a simple model and adding complexity, when new field data was available.
 The field data included information on spill history, distribution of the contaminant (multilevel sampling), geology and hydrogeology.
@@ Line 11: / Line 12: @@
 * [[:Media:Pumping_and_tracer_test_report.pdf |Report about the pumping and tracer tests at Akacievej, Hedehusene (PDF)]]
-[[File:coupled2D-3Dmodel.png|500px|thumb|Fig.1: Coupled 3D source-zone model and 2D plume-scale model.]]
+In 2018, the the hydraulic heads were measured in the plume area, which showed that the flow conditions were fairly constant.
+The picture of the PCE distribution was updated by depth-specific measurements in the source- and plume area using a bladder pump.
 To reduce the numerical effort and to simulate the plume propagation on a larger scale, a 3D source-zone model coupled to a 2D plume-scale model was developed.
 The 3D model resolves flow and transport in the source zone.
@@ Line 21: / Line 22: @@
 * [[:Media:Akacievej-Data-og_modelgrundlag_for_revudering_af_afværgeanlæg.pdf|Akacievej - Data- and modeling basis for the re-evaluation of the remediation system]]
-Since a great part of the PCE contamination is located in the crushed limestone (upper 3-5 m), it was included in the model setup.
+[[File:mapcoupled2D-3Dmodel.png|500px|thumb|Fig.2: Map of the coupled 3D source-zone model and 2D plume-scale model.]]
-The crushed limestone has different hydraulic properties as the fractured limestone.
-The bulk hydraulic conductivity was slightly lower than in the fractured limestone.
+Since the depth-discrete contaminant sampling showed that a great part of the PCE contamination is located in the crushed limestone (upper 3-5 m), the crushed limestone was included in the model setup as a separate layer with different proporties as the fractured limestone.
-No distinct horizontal fractures as in the fractured limestone could be identified.
+The bulk hydraulic conductivity was slightly lower than in the fractured limestone, and no distinct horizontal fractures as in the fractured limestone could be identified.
 Most likely, the fractured limestone contains many more small fractures, small cavities and some larger intact limestone chunks.
 Then, most of the advective transport happens in the conductive areas with a diffusive exchange with lower conductive areas.
 This could be described by a dual-porosity model.
@@ Line 31: / Line 35: @@
 Instead, a homogeneous unit with a unifrom conductivity was used.
 To still account for the immobile areas with storage of contaminant, the sorption coefficient was modified.
 <!--

@@ Line 10: / Line 10: @@
 This is described in detail in the following report:
 * [[:Media:Pumping_and_tracer_test_report.pdf |Report about the pumping and tracer tests at Akacievej, Hedehusene (PDF)]]
 To reduce the numerical effort and to simulate the plume propagation on a larger scale, a 3D source-zone model coupled to a 2D plume-scale model was developed.
@@ Line 15: / Line 17: @@
 Therefore, an initial contaminant distribution in the source zone was implemented, which is based on depth-specific measurements of PCE in the monitoring wells at the Akacievej site.
 The source-zone model was calibrated to the long-term pumping and tracer test and then used to compute the contaminant input fluxes for the 2D model, which starts at the downstream end of the source zone model (Figure 1).
 The following report (in Danish) shows the setup and application of this coupled 3D source-zone and 2D plume-scale model, which supported the re-evaluation of the remediation system at the Akacievej site:
@@ Line 32: / Line 32: @@
 To still account for the immobile areas with storage of contaminant, the sorption coefficient was modified.
 <!--

@@ Line 5: / Line 5: @@
 The field data included information on spill history, distribution of the contaminant (multilevel sampling), geology and hydrogeology.
-To describe the geology and fracture system, data from borehole logs, packer tests, optical televiewers and cores was combined with an analysis of local heterogeneities and data from analogue sites.
+To describe the geology and fracture system, data from borehole logs, packer tests, optical televiewers and cores were combined with an analysis of local heterogeneities and data from analogue sites.
-A pumping and tracer test with depth-specific contaminant sampling was conducted at the site to determine flow and transport parameters of the fractures and matrix and to quantify the contaminant distribution in the aquifer.
+A pumping and tracer test was conducted at the site to determine flow and transport parameters of the fractures and matrix and depth-specific contaminant sampling allowed to characterize the contaminant distribution in the aquifer.
-Different models were used for the planning and interpretation of the pumping and tracer test.
+For the planning and interpretation of the pumping and tracer test models of different complexity were applied.
-This is described in the following report:
+This is described in detail in the following report:
 * [[:Media:Pumping_and_tracer_test_report.pdf |Report about the pumping and tracer tests at Akacievej, Hedehusene (PDF)]]
-To reduce the numerical effort and to simulate the plume propagation on a larger scale, a coupled 2D plume-scale and 3D source-zone model was developed.
+To reduce the numerical effort and to simulate the plume propagation on a larger scale, a 3D source-zone model coupled to a 2D plume-scale model was developed.
 The 3D model resolves flow and transport in the source zone.
-Therefore, an initial contaminant distribution in the source zone was implemented, which is based on depth-specific measurements of PCE.
+Therefore, an initial contaminant distribution in the source zone was implemented, which is based on depth-specific measurements of PCE in the monitoring wells at the Akacievej site.
-The source-zone model is then used to compute the contaminant input fluxes for the 2D model, which starts at the downstream end of the source zone model.
+The source-zone model was calibrated to the long-term pumping and tracer test and then used to compute the contaminant input fluxes for the 2D model, which starts at the downstream end of the source zone model (Figure 1).
 The following report (in Danish) shows the setup and application of this coupled 3D source-zone and 2D plume-scale model, which supported the re-evaluation of the remediation system at the Akacievej site:

@@ Line 1: / Line 1: @@
 == Example: Setup and application of models for a field site (Akacievej, Hedehusene) ==
-First, several models were compared for a contaminated site in Denmark, where a plume of dissolved PCE has migrated through a fractured limestone aquifer.
+First, several models were compared for the [[The Akacievej field site|'''Akacievej site''']], where a plume of dissolved PCE had spread in a fractured limestone aquifer and where a remediation system was in the process of re-evaluation.
-Numerical modeling was integrated in the planning of field tests and in the update of the conceptual model.
+Numerical modeling was integrated in the planning of field tests and in the update of the conceptual model of the contaminated site.
 Field data includes information on spill history, distribution of the contaminant (multilevel sampling), geology and hydrogeology.
 To describe the geology and fracture system, data from borehole logs, packer tests, optical televiewers and cores was combined with an analysis of local heterogeneities and data from analogue sites.

← Older revision		Revision as of 14:44, 3 July 2019
Line 1:		Line 1:
−	== Example: Setup of models for a field site (Akacievej, Hedehusene) ==	+	== Example: Setup and application of models for a field site (Akacievej, Hedehusene) ==

	First, several models were compared for a contaminated site in Denmark, where a plume of dissolved PCE has migrated through a fractured limestone aquifer.		First, several models were compared for a contaminated site in Denmark, where a plume of dissolved PCE has migrated through a fractured limestone aquifer.

@@ Line 6: / Line 6: @@
 Field data includes information on spill history, distribution of the contaminant (multilevel sampling), geology and hydrogeology.
 To describe the geology and fracture system, data from borehole logs, packer tests, optical televiewers and cores was combined with an analysis of local heterogeneities and data from analogue sites.
-A pump and tracer test with contaminant sampling was performed at the site to determine flow and transport parameters of the fractures and matrix and to quantify the contaminant distribution in the aquifer. Different models were used for the planning and interpretation of the pumping and tracer test.
+A pumping and tracer test with contaminant sampling was performed at the site to determine flow and transport parameters of the fractures and matrix and to quantify the contaminant distribution in the aquifer. Different models were used for the planning and interpretation of the pumping and tracer test.
 <!--
 The report below (in Danish) shows the setup and application of different numerical models as basis for the re-evaluation of the remediation system at the Akacievej site.