real-time plume delineation using low-level mihpt … · gry sander janniche, charlotte riis and...
TRANSCRIPT
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundw
ater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx10
5)
PCE, lab (µg/L)
LL-MIH
PT-LOG
VS. SO
IL CO
RESExam
ple of LL-XSD
log (MI202) w
ith results from corresponding soil core sam
ples and depth specific water sam
ples. The M
i202 log was carried out as part of a back diffusion project.
Plumes of dissolved contam
inants may be w
idely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plum
e contaminant levels are generally m
uch lower than source
area concentrations. Characterization and delineation of contam
inant plum
es therefore typically require many investigation points at great
depths. Often the delineation of a contam
inant plume is conducted
using traditional drilling techniques and installation of screened wells.
How
ever, this method is both tim
e-consuming and resource-intensive
and only a limited num
ber of discrete depths can be screened in each w
ell. Furthermore, screen depths are often chosen based on expect-
ed flow and contam
inant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contam
i-nant distribution.
On behalf of The C
apital Region of Denm
ark and in cooperation with
Geoprobe System
s (US), N
IRAS (D
K) has tested a novel tool, Low-
Level MIH
PT (LL-MIH
PT), for delineation and characterization of con-tam
inant plumes in groundw
ater. The purpose of the project was to
test the LL-MIH
PT technique for delineation of contaminant plum
es at tw
o sites with different geological form
ations; sandy and clayey, re-spectively. The objectives have thus been to determ
ine at which con-
centration level the LL-MIH
PT system could detect the site specific
contaminants and to investigate the correlation betw
een observed LL-M
IHPT responses and results from
analysed water and soil core sam
-ples from
targeted depths.
The LL-MIH
PT system is based on the existing high resolution direct
push investigation tools MIP and H
PT developed by Geoprobe Sys-
tems and it is developed w
ith the objective to detect contamination
at low concentrations.
The LL-MIH
PT system has been tested at tw
o sites in Denm
ark as part of ongoing field investigations. 9 LL-M
IHPT logs to 20-25 m
eters be-low
surface have been carried out. At each log location, w
ater sam-
ples were collected at specific depths for verification of the observed
responses from the LL-M
IHPT and for correlation of contam
ination levels. For further correlation of the LL-M
IHPT data, core sam
ples w
ere collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since
then, NIRA
S has used the LL-MIH
PT system in field investigations at
several other sites (including investigations of contaminant back diffu-
sion from low
permeable layers).
Representative results are presented below.
The results from the field tests show
that it is possible with the LL-M
I-H
PT to track relatively low concentrations of chlorinated solvents and
BTEX’s in the saturated zone. H
ence, for chlorinated solvents a de-tection lim
it in the order of 10 microgram
/L has been achieved with
an optimized detector system
. For comparison the detection lim
it for chlorinated solvents w
ith the standard MIP system
is in the order of 500 m
icrogram/L.
Based on the results obtained from the field tests the LL-M
IHPT sys-
tem has proven valuable for real-tim
e delineation of contaminant
plumes in the saturated zone w
ith simultaneous retrieval of hydro-
stratigraphic data. Thus, LL-MIH
PT logs followed by depth specific
groundwater sam
pling is considered to be an optimal com
bination of tools for delineation and characterization of contam
inant plumes in
saturated zones in unconsolidated geological formations. The com
-bined output data can be used directly for m
ass flux estimates.
Furthermore the LL-M
IHPT system
may be a good tool for investiga-
tions of back diffusion in unconsolidated permeable geological set-
tings.
REAL-TIM
E PLUM
E DELIN
EATION
USIN
G LO
W-LEV
EL MIH
PT (LL-M
IHPT)
Geoprobe System
s®
Malen
e Tørn
qvist F
ront,
Gry S
and
er Jannich
e, Charlo
tte Riis
and
And
ers Geo
rg C
hristen
sen
NIRA
S, Alleroed, D
enmark
Dan P
ipp
G
eoprobe Systems, Salina, K
S, USA
Nancy H
am
burg
er and
Ped
er Johansen
C
apital Region of Denm
ark, Hilleroed, D
enmark
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µg/L
Groundw
atersampling
(eg. screenedw
ellsor
levelspecificw
/ Geoprobe)
incl. HPT logs
CO
NCEP
TS O
F T
HE L
L-MIP
/MIH
PT
SY
ST
EM
FIE
LD
ACT
IVIT
IES
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µ g/L
Groundw
aterSam
pling incl. H
PT logs
> 10 µg/L
LL-MIP / LL-M
iHPT
Activities at a form
er dry cleaning facility have caused pollution of soil and groundw
ater with chlorinated solvents (prim
arily PCE). Form
er investigations show
that a plume of dissolved PC
E has spread more
than 200 meters from
the hotspot area and in depths of 4-17 m bgs.
In order to further delinate the plume, three LL-M
IHPT logs w
ere per-form
ed in 2013. Additionally three LL-M
IHPT logs w
ere performed as
part of a project describing back diffusion from low
permeable layers
in the plume.
CO
NCLU
SIO
N A
ND
PER
SP
ECT
IVES
TRAD
ITION
AL IN
VESTIG
ATION
METH
OD
OLO
GY
Conceptual m
odel of a contaminant plum
e from a hotspot area.
The range of investigation techniques available for delination of contaminant plum
es is limited and often the delineation
of a plume is conducted taking out several groundw
ater samples.
RESU
LTS
LL-MIH
PT SYSTEM
Concepts of LL-M
IP/MIH
PT. The LL-MIP/M
IHPT system
is based on the existing MIP/M
IHPT system
. Only an additional con-
trol unit, MIP Pulse Flow
Controller (incl. softw
are), is required. The carrier gas stream is pulsed, w
hich allows a build-up of
contaminant m
ass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a low
er detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autum
n 2013
Test of LL-MiHPT,
Summ
er 2013
Back diffusion
project, 2013/2014
LL-MIH
PT-LOG
VS W
ATER SAM
PLESExam
ple of LL-MIH
PT log (GB128) w
ith results from corresponding depth specific w
ater samples. R
ed lin
e: LL-XSD
log. B
lack
line: H
PT log. Blu
e line: G
roundwater level. D
epth specific water sam
pling have been carried out within intervals
of only 10 cm.
The results from G
B128 show good correlation betw
een LL-XSD
re-sponses and m
easured concentrations of chlorinated solvents. How
-ever, a concentration of for instance 3 m
icrogram/L did not give rise
to significant LL-XSD
responses. At the bottom
of the LL-XSD
log there seem
s to be false positive responses. This should always be veri-
fied by analyses of water sam
ples. The log GB128 also show
s that the contam
inant mass is associated w
ith layers of lower perm
eability (higher H
PT pressure).
BA
CK
GR
OU
ND
LL-MIH
PT RESPON
SE TO D
EGRA
DATIO
N PRO
DU
CTS
Example of LL-M
IHPT log w
ith results from corresponding depth specific w
ater samples from
a site with groundw
ater con-tam
ination constituting primarily of degradation products of chlorinated solvents.
Red
line: LL-X
SD log G
reen lin
e: HPT log
Deg
rad
atio
n p
rod
ucts
The figure shows that the m
ost significant LL-XSD
responses are ob-served just above a low
permeable layer (clay). LL-X
SD responses at
the top of the low perm
eable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show
good correlation betw
een observed LL-XSD
responses and measured concentrations of
degradation products of chlorinated solvents in water sam
ples.
The results from the M
i202 log show good correlation betw
een LL-X
SD responses and m
easured concentrations of PCE in soil core sam
-ples and pore w
ater.
May 2016
GV
S
Elevation [m]
(GB
128)
7
25
30,2
0,2 0,4
NO
VEL IN
VESTIG
ATIO
N M
ETHO
DO
LOG
Y
TEST SITE
OB
JECT
IVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_M
ILJ_MA
F_VIG
_REV_B.indd 1
12-05-2016 11:14:00 page 2/6
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundw
ater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx10
5)
PCE, lab (µg/L)
LL-MIH
PT-LOG
VS. SO
IL CO
RESExam
ple of LL-XSD
log (MI202) w
ith results from corresponding soil core sam
ples and depth specific water sam
ples. The M
i202 log was carried out as part of a back diffusion project.
Plumes of dissolved contam
inants may be w
idely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plum
e contaminant levels are generally m
uch lower than source
area concentrations. Characterization and delineation of contam
inant plum
es therefore typically require many investigation points at great
depths. Often the delineation of a contam
inant plume is conducted
using traditional drilling techniques and installation of screened wells.
How
ever, this method is both tim
e-consuming and resource-intensive
and only a limited num
ber of discrete depths can be screened in each w
ell. Furthermore, screen depths are often chosen based on expect-
ed flow and contam
inant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contam
i-nant distribution.
On behalf of The C
apital Region of Denm
ark and in cooperation with
Geoprobe System
s (US), N
IRAS (D
K) has tested a novel tool, Low-
Level MIH
PT (LL-MIH
PT), for delineation and characterization of con-tam
inant plumes in groundw
ater. The purpose of the project was to
test the LL-MIH
PT technique for delineation of contaminant plum
es at tw
o sites with different geological form
ations; sandy and clayey, re-spectively. The objectives have thus been to determ
ine at which con-
centration level the LL-MIH
PT system could detect the site specific
contaminants and to investigate the correlation betw
een observed LL-M
IHPT responses and results from
analysed water and soil core sam
-ples from
targeted depths.
The LL-MIH
PT system is based on the existing high resolution direct
push investigation tools MIP and H
PT developed by Geoprobe Sys-
tems and it is developed w
ith the objective to detect contamination
at low concentrations.
The LL-MIH
PT system has been tested at tw
o sites in Denm
ark as part of ongoing field investigations. 9 LL-M
IHPT logs to 20-25 m
eters be-low
surface have been carried out. At each log location, w
ater sam-
ples were collected at specific depths for verification of the observed
responses from the LL-M
IHPT and for correlation of contam
ination levels. For further correlation of the LL-M
IHPT data, core sam
ples w
ere collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since
then, NIRA
S has used the LL-MIH
PT system in field investigations at
several other sites (including investigations of contaminant back diffu-
sion from low
permeable layers).
Representative results are presented below.
The results from the field tests show
that it is possible with the LL-M
I-H
PT to track relatively low concentrations of chlorinated solvents and
BTEX’s in the saturated zone. H
ence, for chlorinated solvents a de-tection lim
it in the order of 10 microgram
/L has been achieved with
an optimized detector system
. For comparison the detection lim
it for chlorinated solvents w
ith the standard MIP system
is in the order of 500 m
icrogram/L.
Based on the results obtained from the field tests the LL-M
IHPT sys-
tem has proven valuable for real-tim
e delineation of contaminant
plumes in the saturated zone w
ith simultaneous retrieval of hydro-
stratigraphic data. Thus, LL-MIH
PT logs followed by depth specific
groundwater sam
pling is considered to be an optimal com
bination of tools for delineation and characterization of contam
inant plumes in
saturated zones in unconsolidated geological formations. The com
-bined output data can be used directly for m
ass flux estimates.
Furthermore the LL-M
IHPT system
may be a good tool for investiga-
tions of back diffusion in unconsolidated permeable geological set-
tings.
REAL-TIM
E PLUM
E DELIN
EATION
USIN
G LO
W-LEV
EL MIH
PT (LL-M
IHPT)
Geoprobe System
s®
Malen
e Tørn
qvist F
ront,
Gry S
and
er Jannich
e, Charlo
tte Riis
and
And
ers Geo
rg C
hristen
sen
NIRA
S, Alleroed, D
enmark
Dan P
ipp
G
eoprobe Systems, Salina, K
S, USA
Nancy H
am
burg
er and
Ped
er Johansen
C
apital Region of Denm
ark, Hilleroed, D
enmark
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µg/L
Groundw
atersampling
(eg. screenedw
ellsor
levelspecificw
/ Geoprobe)
incl. HPT logs
CO
NCEP
TS O
F T
HE L
L-MIP
/MIH
PT
SY
ST
EM
FIE
LD
ACT
IVIT
IES
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µ g/L
Groundw
aterSam
pling incl. H
PT logs
> 10 µg/L
LL-MIP / LL-M
iHPT
Activities at a form
er dry cleaning facility have caused pollution of soil and groundw
ater with chlorinated solvents (prim
arily PCE). Form
er investigations show
that a plume of dissolved PC
E has spread more
than 200 meters from
the hotspot area and in depths of 4-17 m bgs.
In order to further delinate the plume, three LL-M
IHPT logs w
ere per-form
ed in 2013. Additionally three LL-M
IHPT logs w
ere performed as
part of a project describing back diffusion from low
permeable layers
in the plume.
CO
NCLU
SIO
N A
ND
PER
SP
ECT
IVES
TRAD
ITION
AL IN
VESTIG
ATION
METH
OD
OLO
GY
Conceptual m
odel of a contaminant plum
e from a hotspot area.
The range of investigation techniques available for delination of contaminant plum
es is limited and often the delineation
of a plume is conducted taking out several groundw
ater samples.
RESU
LTS
LL-MIH
PT SYSTEM
Concepts of LL-M
IP/MIH
PT. The LL-MIP/M
IHPT system
is based on the existing MIP/M
IHPT system
. Only an additional con-
trol unit, MIP Pulse Flow
Controller (incl. softw
are), is required. The carrier gas stream is pulsed, w
hich allows a build-up of
contaminant m
ass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a low
er detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autum
n 2013
Test of LL-MiHPT,
Summ
er 2013
Back diffusion
project, 2013/2014
LL-MIH
PT-LOG
VS W
ATER SAM
PLESExam
ple of LL-MIH
PT log (GB128) w
ith results from corresponding depth specific w
ater samples. R
ed lin
e: LL-XSD
log. B
lack
line: H
PT log. Blu
e line: G
roundwater level. D
epth specific water sam
pling have been carried out within intervals
of only 10 cm.
The results from G
B128 show good correlation betw
een LL-XSD
re-sponses and m
easured concentrations of chlorinated solvents. How
-ever, a concentration of for instance 3 m
icrogram/L did not give rise
to significant LL-XSD
responses. At the bottom
of the LL-XSD
log there seem
s to be false positive responses. This should always be veri-
fied by analyses of water sam
ples. The log GB128 also show
s that the contam
inant mass is associated w
ith layers of lower perm
eability (higher H
PT pressure).
BA
CK
GR
OU
ND
LL-MIH
PT RESPON
SE TO D
EGRA
DATIO
N PRO
DU
CTS
Example of LL-M
IHPT log w
ith results from corresponding depth specific w
ater samples from
a site with groundw
ater con-tam
ination constituting primarily of degradation products of chlorinated solvents.
Red
line: LL-X
SD log G
reen lin
e: HPT log
Deg
rad
atio
n p
rod
ucts
The figure shows that the m
ost significant LL-XSD
responses are ob-served just above a low
permeable layer (clay). LL-X
SD responses at
the top of the low perm
eable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show
good correlation betw
een observed LL-XSD
responses and measured concentrations of
degradation products of chlorinated solvents in water sam
ples.
The results from the M
i202 log show good correlation betw
een LL-X
SD responses and m
easured concentrations of PCE in soil core sam
-ples and pore w
ater.
May 2016
GV
S
Elevation [m]
(GB
128)
7
25
30,2
0,2 0,4
NO
VEL IN
VESTIG
ATIO
N M
ETHO
DO
LOG
Y
TEST SITE
OB
JECT
IVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_M
ILJ_MA
F_VIG
_REV_B.indd 1
12-05-2016 11:14:00 page 3/6
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundw
ater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx10
5)
PCE, lab (µg/L)
LL-MIH
PT-LOG
VS. SO
IL CO
RESExam
ple of LL-XSD
log (MI202) w
ith results from corresponding soil core sam
ples and depth specific water sam
ples. The M
i202 log was carried out as part of a back diffusion project.
Plumes of dissolved contam
inants may be w
idely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plum
e contaminant levels are generally m
uch lower than source
area concentrations. Characterization and delineation of contam
inant plum
es therefore typically require many investigation points at great
depths. Often the delineation of a contam
inant plume is conducted
using traditional drilling techniques and installation of screened wells.
How
ever, this method is both tim
e-consuming and resource-intensive
and only a limited num
ber of discrete depths can be screened in each w
ell. Furthermore, screen depths are often chosen based on expect-
ed flow and contam
inant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contam
i-nant distribution.
On behalf of The C
apital Region of Denm
ark and in cooperation with
Geoprobe System
s (US), N
IRAS (D
K) has tested a novel tool, Low-
Level MIH
PT (LL-MIH
PT), for delineation and characterization of con-tam
inant plumes in groundw
ater. The purpose of the project was to
test the LL-MIH
PT technique for delineation of contaminant plum
es at tw
o sites with different geological form
ations; sandy and clayey, re-spectively. The objectives have thus been to determ
ine at which con-
centration level the LL-MIH
PT system could detect the site specific
contaminants and to investigate the correlation betw
een observed LL-M
IHPT responses and results from
analysed water and soil core sam
-ples from
targeted depths.
The LL-MIH
PT system is based on the existing high resolution direct
push investigation tools MIP and H
PT developed by Geoprobe Sys-
tems and it is developed w
ith the objective to detect contamination
at low concentrations.
The LL-MIH
PT system has been tested at tw
o sites in Denm
ark as part of ongoing field investigations. 9 LL-M
IHPT logs to 20-25 m
eters be-low
surface have been carried out. At each log location, w
ater sam-
ples were collected at specific depths for verification of the observed
responses from the LL-M
IHPT and for correlation of contam
ination levels. For further correlation of the LL-M
IHPT data, core sam
ples w
ere collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since
then, NIRA
S has used the LL-MIH
PT system in field investigations at
several other sites (including investigations of contaminant back diffu-
sion from low
permeable layers).
Representative results are presented below.
The results from the field tests show
that it is possible with the LL-M
I-H
PT to track relatively low concentrations of chlorinated solvents and
BTEX’s in the saturated zone. H
ence, for chlorinated solvents a de-tection lim
it in the order of 10 microgram
/L has been achieved with
an optimized detector system
. For comparison the detection lim
it for chlorinated solvents w
ith the standard MIP system
is in the order of 500 m
icrogram/L.
Based on the results obtained from the field tests the LL-M
IHPT sys-
tem has proven valuable for real-tim
e delineation of contaminant
plumes in the saturated zone w
ith simultaneous retrieval of hydro-
stratigraphic data. Thus, LL-MIH
PT logs followed by depth specific
groundwater sam
pling is considered to be an optimal com
bination of tools for delineation and characterization of contam
inant plumes in
saturated zones in unconsolidated geological formations. The com
-bined output data can be used directly for m
ass flux estimates.
Furthermore the LL-M
IHPT system
may be a good tool for investiga-
tions of back diffusion in unconsolidated permeable geological set-
tings.
REAL-TIM
E PLUM
E DELIN
EATION
USIN
G LO
W-LEV
EL MIH
PT (LL-M
IHPT)
Geoprobe System
s®
Malen
e Tørn
qvist F
ront,
Gry S
and
er Jannich
e, Charlo
tte Riis
and
And
ers Geo
rg C
hristen
sen
NIRA
S, Alleroed, D
enmark
Dan P
ipp
G
eoprobe Systems, Salina, K
S, USA
Nancy H
am
burg
er and
Ped
er Johansen
C
apital Region of Denm
ark, Hilleroed, D
enmark
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µg/L
Groundw
atersampling
(eg. screenedw
ellsor
levelspecificw
/ Geoprobe)
incl. HPT logs
CO
NCEP
TS O
F T
HE L
L-MIP
/MIH
PT
SY
ST
EM
FIE
LD
ACT
IVIT
IES
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µ g/L
Groundw
aterSam
pling incl. H
PT logs
> 10 µg/L
LL-MIP / LL-M
iHPT
Activities at a form
er dry cleaning facility have caused pollution of soil and groundw
ater with chlorinated solvents (prim
arily PCE). Form
er investigations show
that a plume of dissolved PC
E has spread more
than 200 meters from
the hotspot area and in depths of 4-17 m bgs.
In order to further delinate the plume, three LL-M
IHPT logs w
ere per-form
ed in 2013. Additionally three LL-M
IHPT logs w
ere performed as
part of a project describing back diffusion from low
permeable layers
in the plume.
CO
NCLU
SIO
N A
ND
PER
SP
ECT
IVES
TRAD
ITION
AL IN
VESTIG
ATION
METH
OD
OLO
GY
Conceptual m
odel of a contaminant plum
e from a hotspot area.
The range of investigation techniques available for delination of contaminant plum
es is limited and often the delineation
of a plume is conducted taking out several groundw
ater samples.
RESU
LTS
LL-MIH
PT SYSTEM
Concepts of LL-M
IP/MIH
PT. The LL-MIP/M
IHPT system
is based on the existing MIP/M
IHPT system
. Only an additional con-
trol unit, MIP Pulse Flow
Controller (incl. softw
are), is required. The carrier gas stream is pulsed, w
hich allows a build-up of
contaminant m
ass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a low
er detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autum
n 2013
Test of LL-MiHPT,
Summ
er 2013
Back diffusion
project, 2013/2014
LL-MIH
PT-LOG
VS W
ATER SAM
PLESExam
ple of LL-MIH
PT log (GB128) w
ith results from corresponding depth specific w
ater samples. R
ed lin
e: LL-XSD
log. B
lack
line: H
PT log. Blu
e line: G
roundwater level. D
epth specific water sam
pling have been carried out within intervals
of only 10 cm.
The results from G
B128 show good correlation betw
een LL-XSD
re-sponses and m
easured concentrations of chlorinated solvents. How
-ever, a concentration of for instance 3 m
icrogram/L did not give rise
to significant LL-XSD
responses. At the bottom
of the LL-XSD
log there seem
s to be false positive responses. This should always be veri-
fied by analyses of water sam
ples. The log GB128 also show
s that the contam
inant mass is associated w
ith layers of lower perm
eability (higher H
PT pressure).
BA
CK
GR
OU
ND
LL-MIH
PT RESPON
SE TO D
EGRA
DATIO
N PRO
DU
CTS
Example of LL-M
IHPT log w
ith results from corresponding depth specific w
ater samples from
a site with groundw
ater con-tam
ination constituting primarily of degradation products of chlorinated solvents.
Red
line: LL-X
SD log G
reen lin
e: HPT log
Deg
rad
atio
n p
rod
ucts
The figure shows that the m
ost significant LL-XSD
responses are ob-served just above a low
permeable layer (clay). LL-X
SD responses at
the top of the low perm
eable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show
good correlation betw
een observed LL-XSD
responses and measured concentrations of
degradation products of chlorinated solvents in water sam
ples.
The results from the M
i202 log show good correlation betw
een LL-X
SD responses and m
easured concentrations of PCE in soil core sam
-ples and pore w
ater.
May 2016
GV
S
Elevation [m]
(GB
128)
7
25
30,2
0,2 0,4
NO
VEL IN
VESTIG
ATIO
N M
ETHO
DO
LOG
Y
TEST SITE
OB
JECT
IVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_M
ILJ_MA
F_VIG
_REV_B.indd 1
12-05-2016 11:14:00 page 4/6
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundw
ater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx10
5)
PCE, lab (µg/L)
LL-MIH
PT-LOG
VS. SO
IL CO
RESExam
ple of LL-XSD
log (MI202) w
ith results from corresponding soil core sam
ples and depth specific water sam
ples. The M
i202 log was carried out as part of a back diffusion project.
Plumes of dissolved contam
inants may be w
idely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plum
e contaminant levels are generally m
uch lower than source
area concentrations. Characterization and delineation of contam
inant plum
es therefore typically require many investigation points at great
depths. Often the delineation of a contam
inant plume is conducted
using traditional drilling techniques and installation of screened wells.
How
ever, this method is both tim
e-consuming and resource-intensive
and only a limited num
ber of discrete depths can be screened in each w
ell. Furthermore, screen depths are often chosen based on expect-
ed flow and contam
inant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contam
i-nant distribution.
On behalf of The C
apital Region of Denm
ark and in cooperation with
Geoprobe System
s (US), N
IRAS (D
K) has tested a novel tool, Low-
Level MIH
PT (LL-MIH
PT), for delineation and characterization of con-tam
inant plumes in groundw
ater. The purpose of the project was to
test the LL-MIH
PT technique for delineation of contaminant plum
es at tw
o sites with different geological form
ations; sandy and clayey, re-spectively. The objectives have thus been to determ
ine at which con-
centration level the LL-MIH
PT system could detect the site specific
contaminants and to investigate the correlation betw
een observed LL-M
IHPT responses and results from
analysed water and soil core sam
-ples from
targeted depths.
The LL-MIH
PT system is based on the existing high resolution direct
push investigation tools MIP and H
PT developed by Geoprobe Sys-
tems and it is developed w
ith the objective to detect contamination
at low concentrations.
The LL-MIH
PT system has been tested at tw
o sites in Denm
ark as part of ongoing field investigations. 9 LL-M
IHPT logs to 20-25 m
eters be-low
surface have been carried out. At each log location, w
ater sam-
ples were collected at specific depths for verification of the observed
responses from the LL-M
IHPT and for correlation of contam
ination levels. For further correlation of the LL-M
IHPT data, core sam
ples w
ere collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since
then, NIRA
S has used the LL-MIH
PT system in field investigations at
several other sites (including investigations of contaminant back diffu-
sion from low
permeable layers).
Representative results are presented below.
The results from the field tests show
that it is possible with the LL-M
I-H
PT to track relatively low concentrations of chlorinated solvents and
BTEX’s in the saturated zone. H
ence, for chlorinated solvents a de-tection lim
it in the order of 10 microgram
/L has been achieved with
an optimized detector system
. For comparison the detection lim
it for chlorinated solvents w
ith the standard MIP system
is in the order of 500 m
icrogram/L.
Based on the results obtained from the field tests the LL-M
IHPT sys-
tem has proven valuable for real-tim
e delineation of contaminant
plumes in the saturated zone w
ith simultaneous retrieval of hydro-
stratigraphic data. Thus, LL-MIH
PT logs followed by depth specific
groundwater sam
pling is considered to be an optimal com
bination of tools for delineation and characterization of contam
inant plumes in
saturated zones in unconsolidated geological formations. The com
-bined output data can be used directly for m
ass flux estimates.
Furthermore the LL-M
IHPT system
may be a good tool for investiga-
tions of back diffusion in unconsolidated permeable geological set-
tings.
REAL-TIM
E PLUM
E DELIN
EATION
USIN
G LO
W-LEV
EL MIH
PT (LL-M
IHPT)
Geoprobe System
s®
Malen
e Tørn
qvist F
ront,
Gry S
and
er Jannich
e, Charlo
tte Riis
and
And
ers Geo
rg C
hristen
sen
NIRA
S, Alleroed, D
enmark
Dan P
ipp
G
eoprobe Systems, Salina, K
S, USA
Nancy H
am
burg
er and
Ped
er Johansen
C
apital Region of Denm
ark, Hilleroed, D
enmark
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µg/L
Groundw
atersampling
(eg. screenedw
ellsor
levelspecificw
/ Geoprobe)
incl. HPT logs
CO
NCEP
TS O
F T
HE L
L-MIP
/MIH
PT
SY
ST
EM
FIE
LD
ACT
IVIT
IES
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µ g/L
Groundw
aterSam
pling incl. H
PT logs
> 10 µg/L
LL-MIP / LL-M
iHPT
Activities at a form
er dry cleaning facility have caused pollution of soil and groundw
ater with chlorinated solvents (prim
arily PCE). Form
er investigations show
that a plume of dissolved PC
E has spread more
than 200 meters from
the hotspot area and in depths of 4-17 m bgs.
In order to further delinate the plume, three LL-M
IHPT logs w
ere per-form
ed in 2013. Additionally three LL-M
IHPT logs w
ere performed as
part of a project describing back diffusion from low
permeable layers
in the plume.
CO
NCLU
SIO
N A
ND
PER
SP
ECT
IVES
TRAD
ITION
AL IN
VESTIG
ATION
METH
OD
OLO
GY
Conceptual m
odel of a contaminant plum
e from a hotspot area.
The range of investigation techniques available for delination of contaminant plum
es is limited and often the delineation
of a plume is conducted taking out several groundw
ater samples.
RESU
LTS
LL-MIH
PT SYSTEM
Concepts of LL-M
IP/MIH
PT. The LL-MIP/M
IHPT system
is based on the existing MIP/M
IHPT system
. Only an additional con-
trol unit, MIP Pulse Flow
Controller (incl. softw
are), is required. The carrier gas stream is pulsed, w
hich allows a build-up of
contaminant m
ass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a low
er detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autum
n 2013
Test of LL-MiHPT,
Summ
er 2013
Back diffusion
project, 2013/2014
LL-MIH
PT-LOG
VS W
ATER SAM
PLESExam
ple of LL-MIH
PT log (GB128) w
ith results from corresponding depth specific w
ater samples. R
ed lin
e: LL-XSD
log. B
lack
line: H
PT log. Blu
e line: G
roundwater level. D
epth specific water sam
pling have been carried out within intervals
of only 10 cm.
The results from G
B128 show good correlation betw
een LL-XSD
re-sponses and m
easured concentrations of chlorinated solvents. How
-ever, a concentration of for instance 3 m
icrogram/L did not give rise
to significant LL-XSD
responses. At the bottom
of the LL-XSD
log there seem
s to be false positive responses. This should always be veri-
fied by analyses of water sam
ples. The log GB128 also show
s that the contam
inant mass is associated w
ith layers of lower perm
eability (higher H
PT pressure).
BA
CK
GR
OU
ND
LL-MIH
PT RESPON
SE TO D
EGRA
DATIO
N PRO
DU
CTS
Example of LL-M
IHPT log w
ith results from corresponding depth specific w
ater samples from
a site with groundw
ater con-tam
ination constituting primarily of degradation products of chlorinated solvents.
Red
line: LL-X
SD log G
reen lin
e: HPT log
Deg
rad
atio
n p
rod
ucts
The figure shows that the m
ost significant LL-XSD
responses are ob-served just above a low
permeable layer (clay). LL-X
SD responses at
the top of the low perm
eable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show
good correlation betw
een observed LL-XSD
responses and measured concentrations of
degradation products of chlorinated solvents in water sam
ples.
The results from the M
i202 log show good correlation betw
een LL-X
SD responses and m
easured concentrations of PCE in soil core sam
-ples and pore w
ater.
May 2016
GV
S
Elevation [m]
(GB
128)
7
25
30,2
0,2 0,4
NO
VEL IN
VESTIG
ATIO
N M
ETHO
DO
LOG
Y
TEST SITE
OB
JECT
IVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_M
ILJ_MA
F_VIG
_REV_B.indd 1
12-05-2016 11:14:00 page 5/6
10th of June 2015 AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundwater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx105)
PCE, lab (µg/L)
LL-MIHPT-LOG VS. SOIL CORESExample of LL-XSD log (MI202) with results from corresponding soil core samples and depth specific water samples. The Mi202 log was carried out as part of a back diffusion project.
Plumes of dissolved contaminants may be widely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plume contaminant levels are generally much lower than source area concentrations. Characterization and delineation of contaminant plumes therefore typically require many investigation points at great depths. Often the delineation of a contaminant plume is conducted using traditional drilling techniques and installation of screened wells. However, this method is both time-consuming and resource-intensive and only a limited number of discrete depths can be screened in each well. Furthermore, screen depths are often chosen based on expect-ed flow and contaminant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contami-nant distribution.
On behalf of The Capital Region of Denmark and in cooperation with Geoprobe Systems (US), NIRAS (DK) has tested a novel tool, Low-Level MIHPT (LL-MIHPT), for delineation and characterization of con-taminant plumes in groundwater. The purpose of the project was to test the LL-MIHPT technique for delineation of contaminant plumes at two sites with different geological formations; sandy and clayey, re-spectively. The objectives have thus been to determine at which con-centration level the LL-MIHPT system could detect the site specific contaminants and to investigate the correlation between observed LL-MIHPT responses and results from analysed water and soil core sam-ples from targeted depths.
The LL-MIHPT system is based on the existing high resolution direct push investigation tools MIP and HPT developed by Geoprobe Sys-tems and it is developed with the objective to detect contamination at low concentrations.
The LL-MIHPT system has been tested at two sites in Denmark as part of ongoing field investigations. 9 LL-MIHPT logs to 20-25 meters be-low surface have been carried out. At each log location, water sam-ples were collected at specific depths for verification of the observed responses from the LL-MIHPT and for correlation of contamination levels. For further correlation of the LL-MIHPT data, core samples were collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since then, NIRAS has used the LL-MIHPT system in field investigations at several other sites (including investigations of contaminant back diffu-sion from low permeable layers).
Representative results are presented below.
The results from the field tests show that it is possible with the LL-MI-HPT to track relatively low concentrations of chlorinated solvents and BTEX’s in the saturated zone. Hence, for chlorinated solvents a de-tection limit in the order of 10 microgram/L has been achieved with an optimized detector system. For comparison the detection limit for chlorinated solvents with the standard MIP system is in the order of 500 microgram/L.
Based on the results obtained from the field tests the LL-MIHPT sys-tem has proven valuable for real-time delineation of contaminant plumes in the saturated zone with simultaneous retrieval of hydro-stratigraphic data. Thus, LL-MIHPT logs followed by depth specific groundwater sampling is considered to be an optimal combination of tools for delineation and characterization of contaminant plumes in saturated zones in unconsolidated geological formations. The com-bined output data can be used directly for mass flux estimates.
Furthermore the LL-MIHPT system may be a good tool for investiga-tions of back diffusion in unconsolidated permeable geological set-tings.
REAL-TIME PLUME DELINEATION USING LOW-LEVEL MIHPT (LL-MIHPT)
Geoprobe Systems®
Malene Tørnqvist Front, Gry Sander Janniche, Charlotte Riis and Anders Georg Christensen NIRAS, Alleroed, Denmark
Dan Pipp Geoprobe Systems, Salina, KS, USA
Nancy Hamburger and Peder Johansen Capital Region of Denmark, Hilleroed, Denmark
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
Groundwater sampling (eg. screened wells or level specific w/ Geoprobe)incl. HPT logs
CONCEPTS OF THE LL-MIP/MIHPT SYSTEM
FIELDACTIVITIES
Hotspot Area Contaminant Plume
> 1.000 µg/L
MIP / MiHPT
> 1 µg/L
GroundwaterSampling incl. HPT logs
> 10 µg/L
LL-MIP / LL-MiHPT
Activities at a former dry cleaning facility have caused pollution of soil and groundwater with chlorinated solvents (primarily PCE). Former investigations show that a plume of dissolved PCE has spread more than 200 meters from the hotspot area and in depths of 4-17 m bgs. In order to further delinate the plume, three LL-MIHPT logs were per-formed in 2013. Additionally three LL-MIHPT logs were performed as part of a project describing back diffusion from low permeable layers in the plume.
CONCLUSION AND PERSPECTIVES
TRADITIONAL INVESTIGATION METHODOLOGYConceptual model of a contaminant plume from a hotspot area.The range of investigation techniques available for delination of contaminant plumes is limited and often the delineation of a plume is conducted taking out several groundwater samples.
RESULTS
LL-MIHPT SYSTEMConcepts of LL-MIP/MIHPT. The LL-MIP/MIHPT system is based on the existing MIP/MIHPT system. Only an additional con-trol unit, MIP Pulse Flow Controller (incl. software), is required. The carrier gas stream is pulsed, which allows a build-up of contaminant mass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a lower detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autumn 2013
Test of LL-MiHPT, Summer 2013
Back diffusion project, 2013/2014
LL-MIHPT-LOG VS WATER SAMPLESExample of LL-MIHPT log (GB128) with results from corresponding depth specific water samples. Red line: LL-XSD log. Black line: HPT log. Blue line: Groundwater level. Depth specific water sampling have been carried out within intervals of only 10 cm.
The results from GB128 show good correlation between LL-XSD re-sponses and measured concentrations of chlorinated solvents. How-ever, a concentration of for instance 3 microgram/L did not give rise to significant LL-XSD responses. At the bottom of the LL-XSD log there seems to be false positive responses. This should always be veri-fied by analyses of water samples. The log GB128 also shows that the contaminant mass is associated with layers of lower permeability (higher HPT pressure).
BACKGROUND
LL-MIHPT RESPONSE TO DEGRADATION PRODUCTSExample of LL-MIHPT log with results from corresponding depth specific water samples from a site with groundwater con-tamination constituting primarily of degradation products of chlorinated solvents.Red line: LL-XSD log Green line: HPT log
Degradation products
The figure shows that the most significant LL-XSD responses are ob-served just above a low permeable layer (clay). LL-XSD responses at the top of the low permeable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show good correlation between observed LL-XSD responses and measured concentrations of degradation products of chlorinated solvents in water samples.
The results from the Mi202 log show good correlation between LL-XSD responses and measured concentrations of PCE in soil core sam-ples and pore water.
May 2016
GVS
Ele
vatio
n [m
]
(GB128)
7
25
3
0,2
0,20,4
NOVEL INVESTIGATION METHODOLOGY
TEST SITE
OBJECTIVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_MILJ_MAF_VIG_REV_B.indd 1 12-05-2016 11:14:00
10th of June 2015AquaConSoil Copenhagen 2015
PCE: -TCE: -cDCE: 17VC: 0,8
PCE: -TCE: 0,7cDCE: 1.000VC: 43
Clay
Chlorinated solvents in groundw
ater in µg/L
PCE, lab (mg/kg TS)
PCE, LL-MIP (µVx10
5)
PCE, lab (µg/L)
LL-MIH
PT-LOG
VS. SO
IL CO
RESExam
ple of LL-XSD
log (MI202) w
ith results from corresponding soil core sam
ples and depth specific water sam
ples. The M
i202 log was carried out as part of a back diffusion project.
Plumes of dissolved contam
inants may be w
idely distributed in the saturated zone, i.e. to great depths and over large areas. In additi-on, plum
e contaminant levels are generally m
uch lower than source
area concentrations. Characterization and delineation of contam
inant plum
es therefore typically require many investigation points at great
depths. Often the delineation of a contam
inant plume is conducted
using traditional drilling techniques and installation of screened wells.
How
ever, this method is both tim
e-consuming and resource-intensive
and only a limited num
ber of discrete depths can be screened in each w
ell. Furthermore, screen depths are often chosen based on expect-
ed flow and contam
inant distribution patterns in the saturated zone, rather than on detailed hydrogeological data and vertical contam
i-nant distribution.
On behalf of The C
apital Region of Denm
ark and in cooperation with
Geoprobe System
s (US), N
IRAS (D
K) has tested a novel tool, Low-
Level MIH
PT (LL-MIH
PT), for delineation and characterization of con-tam
inant plumes in groundw
ater. The purpose of the project was to
test the LL-MIH
PT technique for delineation of contaminant plum
es at tw
o sites with different geological form
ations; sandy and clayey, re-spectively. The objectives have thus been to determ
ine at which con-
centration level the LL-MIH
PT system could detect the site specific
contaminants and to investigate the correlation betw
een observed LL-M
IHPT responses and results from
analysed water and soil core sam
-ples from
targeted depths.
The LL-MIH
PT system is based on the existing high resolution direct
push investigation tools MIP and H
PT developed by Geoprobe Sys-
tems and it is developed w
ith the objective to detect contamination
at low concentrations.
The LL-MIH
PT system has been tested at tw
o sites in Denm
ark as part of ongoing field investigations. 9 LL-M
IHPT logs to 20-25 m
eters be-low
surface have been carried out. At each log location, w
ater sam-
ples were collected at specific depths for verification of the observed
responses from the LL-M
IHPT and for correlation of contam
ination levels. For further correlation of the LL-M
IHPT data, core sam
ples w
ere collected at three locations.
The field tests were conducted and evaluated in 2013-2014. Since
then, NIRA
S has used the LL-MIH
PT system in field investigations at
several other sites (including investigations of contaminant back diffu-
sion from low
permeable layers).
Representative results are presented below.
The results from the field tests show
that it is possible with the LL-M
I-H
PT to track relatively low concentrations of chlorinated solvents and
BTEX’s in the saturated zone. H
ence, for chlorinated solvents a de-tection lim
it in the order of 10 microgram
/L has been achieved with
an optimized detector system
. For comparison the detection lim
it for chlorinated solvents w
ith the standard MIP system
is in the order of 500 m
icrogram/L.
Based on the results obtained from the field tests the LL-M
IHPT sys-
tem has proven valuable for real-tim
e delineation of contaminant
plumes in the saturated zone w
ith simultaneous retrieval of hydro-
stratigraphic data. Thus, LL-MIH
PT logs followed by depth specific
groundwater sam
pling is considered to be an optimal com
bination of tools for delineation and characterization of contam
inant plumes in
saturated zones in unconsolidated geological formations. The com
-bined output data can be used directly for m
ass flux estimates.
Furthermore the LL-M
IHPT system
may be a good tool for investiga-
tions of back diffusion in unconsolidated permeable geological set-
tings.
REAL-TIM
E PLUM
E DELIN
EATION
USIN
G LO
W-LEV
EL MIH
PT (LL-M
IHPT)
Geoprobe System
s®
Malen
e Tørn
qvist F
ront,
Gry S
and
er Jannich
e, Charlo
tte Riis
and
And
ers Geo
rg C
hristen
sen
NIRA
S, Alleroed, D
enmark
Dan P
ipp
G
eoprobe Systems, Salina, K
S, USA
Nancy H
am
burg
er and
Ped
er Johansen
C
apital Region of Denm
ark, Hilleroed, D
enmark
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µg/L
Groundw
atersampling
(eg. screenedw
ellsor
levelspecificw
/ Geoprobe)
incl. HPT logs
CO
NCEP
TS O
F T
HE L
L-MIP
/MIH
PT
SY
ST
EM
FIE
LD
ACT
IVIT
IES
HotspotArea
Contam
inantPlume
> 1.000 µg/L
MIP / M
iHPT
> 1 µ g/L
Groundw
aterSam
pling incl. H
PT logs
> 10 µg/L
LL-MIP / LL-M
iHPT
Activities at a form
er dry cleaning facility have caused pollution of soil and groundw
ater with chlorinated solvents (prim
arily PCE). Form
er investigations show
that a plume of dissolved PC
E has spread more
than 200 meters from
the hotspot area and in depths of 4-17 m bgs.
In order to further delinate the plume, three LL-M
IHPT logs w
ere per-form
ed in 2013. Additionally three LL-M
IHPT logs w
ere performed as
part of a project describing back diffusion from low
permeable layers
in the plume.
CO
NCLU
SIO
N A
ND
PER
SP
ECT
IVES
TRAD
ITION
AL IN
VESTIG
ATION
METH
OD
OLO
GY
Conceptual m
odel of a contaminant plum
e from a hotspot area.
The range of investigation techniques available for delination of contaminant plum
es is limited and often the delineation
of a plume is conducted taking out several groundw
ater samples.
RESU
LTS
LL-MIH
PT SYSTEM
Concepts of LL-M
IP/MIH
PT. The LL-MIP/M
IHPT system
is based on the existing MIP/M
IHPT system
. Only an additional con-
trol unit, MIP Pulse Flow
Controller (incl. softw
are), is required. The carrier gas stream is pulsed, w
hich allows a build-up of
contaminant m
ass before it is led to the detectors. This provides a greater signal at the detectors and thereby results in a low
er detection limit.
Dry cleaner
Transect, Spring 2013
Transect, Autum
n 2013
Test of LL-MiHPT,
Summ
er 2013
Back diffusion
project, 2013/2014
LL-MIH
PT-LOG
VS W
ATER SAM
PLESExam
ple of LL-MIH
PT log (GB128) w
ith results from corresponding depth specific w
ater samples. R
ed lin
e: LL-XSD
log. B
lack
line: H
PT log. Blu
e line: G
roundwater level. D
epth specific water sam
pling have been carried out within intervals
of only 10 cm.
The results from G
B128 show good correlation betw
een LL-XSD
re-sponses and m
easured concentrations of chlorinated solvents. How
-ever, a concentration of for instance 3 m
icrogram/L did not give rise
to significant LL-XSD
responses. At the bottom
of the LL-XSD
log there seem
s to be false positive responses. This should always be veri-
fied by analyses of water sam
ples. The log GB128 also show
s that the contam
inant mass is associated w
ith layers of lower perm
eability (higher H
PT pressure).
BA
CK
GR
OU
ND
LL-MIH
PT RESPON
SE TO D
EGRA
DATIO
N PRO
DU
CTS
Example of LL-M
IHPT log w
ith results from corresponding depth specific w
ater samples from
a site with groundw
ater con-tam
ination constituting primarily of degradation products of chlorinated solvents.
Red
line: LL-X
SD log G
reen lin
e: HPT log
Deg
rad
atio
n p
rod
ucts
The figure shows that the m
ost significant LL-XSD
responses are ob-served just above a low
permeable layer (clay). LL-X
SD responses at
the top of the low perm
eable layer indicate a potential of back diffu-sion of chlorinated solvents. The results also show
good correlation betw
een observed LL-XSD
responses and measured concentrations of
degradation products of chlorinated solvents in water sam
ples.
The results from the M
i202 log show good correlation betw
een LL-X
SD responses and m
easured concentrations of PCE in soil core sam
-ples and pore w
ater.
May 2016
GV
S
Elevation [m]
(GB
128)
7
25
30,2
0,2 0,4
NO
VEL IN
VESTIG
ATIO
N M
ETHO
DO
LOG
Y
TEST SITE
OB
JECT
IVES
Poster_2340x1120_Battelle_Conference_2016_22-26_05_M
ILJ_MA
F_VIG
_REV_B.indd 1
12-05-2016 11:14:00 page 6/6