The Mise A La Masse Method and Hydrocarbon Plume ... - Rowan

The Mise A La Masse
Method and Hydrocarbon
Plume Delineation
Crystal L. Mattson
Environmental Fluid Mechanics
November 30, 2004
Outline
Background
Theory
In Depth Case Study
Conclusion
Questions

Carl Schlumberger
Background
French scientist suggested the method in
1920 – “excitation of the mass”
Originally developed to find subsurface ore
bodies
Is now employed for use in
Mining
Seismic sounding
Subsurface plume delineation
Background (ctd)
Geophysical method
Electrical
Surficial
Other geophysical methods
Ground Penetrating Radar - GPR
Electromagnetic Induction – EM
Magnetometry - MAG

Theory
The equipotential method
This method was one of the earliest used
electrical methods for subsurface exploration
Electrical energy is applied to two (2) points
on the ground surface
Current flows between them because of their
difference in potential
If the medium is homogeneous, the current and
potential distribution is regular and can thus be
calculated
Theory (ctd)
When good or poor conductors are in the
medium
Distortion of the field occurs
Good conductors attract current lines
Poor conductors force current flow away

Theory (ctd)
Mise A La Masse (“MALM”) is a variant on
the equipotential method
Electrode array
Uses the conductive mass under investigation as a
current electrode
Other electrodes are placed radially at regular
intervals
The potential distributions created from the
electrode array can be used to map the
boundaries of an unknown subsurface mass
Theory (ctd)
Basic analogy between electrical flow and
groundwater flow is seen in the governing
equations:
Ohm's
Law :
∂V
J x = −σ
∂x
where :
J x = current density
σ = electrical conductivity
V = electrical potential
Darcy's
Law :
∂h
υx
= −K
∂x
where :
υx
=
K =
h =
specific discharge
hydraulic conductivity
hydraulic head

Theory (ctd)
Steady state flow described by 3D forms of the
Laplace equation
Electrical Flow:
∂
2
V ∂
2
V ∂
2
V
+ + = 0
∂x
2
∂y
2
∂z
2
Groundwater Flow:
∂
2
h ∂
2
h ∂
2
h
+ + = 0
∂x
2
∂y
2
∂z
2
Theory (ctd)
The Laplace Equation in spherical coordinates
1 ∂
1
1
2
⎛ 2 ∂V
⎞ ∂ ⎛ ∂V
⎞ ∂ V
sin ⎟ +
= 0
2
⎜ r ⎟ +
2
⎜ θ
r ∂r
⎝ ∂r
⎠ r sinθ
∂θ
⎝ ∂θ
⎠ r
2
sinθ
∂φ
2
θ = polar angle
φ = azimuth angle
r = radial distance from the current electrode

Theory (ctd)
Keller and Frischknecht (1966)
Single point source of current
Complete symmetry of current flow can be assumed
θ and φ may be eliminated
∂ ⎛
⎜r
∂r
⎝
2
∂V
∂r
⎞
⎟ = 0
⎠
CASE STUDY

Environmental Setting
1.77 acre commercially developed parcel in
northern New Jersey
Located within the Piedmont Province of New
Jersey
Underlain by the Passaic formation
Reddish/brown to brownish/purple and grayish/red shale,
siltstone, mudstone, sandstone, and conglomerates
Unconsolidated sediments are stratified and unstratified
glacial till ranging from fine clays and silts to gravel and
boulders
Onsite soils have been classified as “Urban
land” by the USDA SCS

Site investigations completed previously
by other consulting engineering firms
Draft ASTM Phase I ESA Report (April 2004)
Geotechnical Engineering Report (April 2004)
Revised Hazardous Materials Investigation
report (July 2004)
Limited Phase II Site Investigation (dated July
2004)
The Phase I identified several recognized areas
of environmental concern (RECs) and areas of
concern (AOCs)
Stained soils were encountered during
geotechnical investigations
Further investigation revealed the following:
One (1) 3,000-gallon diesel underground storage tank
(UST) and one (1) 2,000-gallon gasoline UST were
removed in 1992
The NJDEP issued a No Further Action (NFA) letter for this
AOC on September 30, 1994. Residual soil impact
associated with this AOC may remain at the site based on
the results of the previous geotechnical borings
One (1) 550-gallon fuel oil UST located on the north
side of Building #1 was abandoned in place in 1992

Onsite contamination was discovered
during routine groundwater sampling
Chlorinated groundwater was attributed to an
offsite source
Former chemical company located upgradient
Site is currently being investigated
Hydrocarbon impact in MW-3 could not be
definitively attributed to the former gasoline
and diesel USTs
The NJDEP granted a NFA for the area
Limited soil laboratory analysis confirmed
the presence of hydrocarbons
Concentrations were below the NJDEP
IGWSCC
Samples were not collected according to
the NJAC 7:26E Technical Requirements
for Site Remediation or the NJDEP Field
Sampling Procedures Manual
Vertical and horizontal delineation of impacted
soils was not completed!!

Current Remedial Investigations
Pennoni Associates, Inc. is the current
environmental consultant on the project
Soil borings and sampling
Routine groundwater sampling
Separate Phase Product (SPP) in MW-3!
Installation of 2 additional monitoring wells
MALM to delineate the plume
More soil and groundwater sampling…
AREA OF
SUSPECTED IMPACT

MALM Plume Delineation
Pennoni subcontracted out for the MALM
Contracted firm specializes exclusively in nonintrusive,
non-destructive geophysics
Privately owned woman business enterprise
The MALM survey was conducted in the
vicinity of MW-3
MALM Survey Setup

MALM Survey In Action
Boreholes drilled radially around MW-3
Electrodes inserted and connected to
resistivity meter
Water is poured into boreholes
Current turned on and resistivities
measured
Electrode Array

MALM
Measurements are downloaded
GPS points are taken for reference
Pennoni supplied subcontractor with base
plan of existing site conditions
Contours of variations in resistivity were
calculated and plotted
MALM Results

Additional Sampling
Soil borings were completed along
measured plume boundaries
Confirm horizontal boundary of plume
Determine location of soil impact that falls
below IGWSCC
Present remedial options to client
Conclusions
MALM is an old technology that is being
used in new areas
Mathematics are used to calculate the
boundaries of subsurface contaminant
plumes based on electrical resistivity
MALM is an effective, non-intrusive
geophysical method to determine the
presence and boundaries of SPP in
subsurface soils

Selected References
Osiensky, J.L., P.R. Donaldson (1995), “Electrical flow through an
aquifer for contaminant source leak detection and delineation of
plume evolution”, Journal of Hydrology, v. 169, pp. 243-263.
J.L. Osiensky (1997), “Ground water modeling of mise-a-la-masse
delineation of contaminated ground water plumes”, Journal of
Hydrology, v. 197, pp. 146-165.
United States Army Corps of Engineers (1995), “Engineering and
Design: Geophysical Exploration for Engineering and Environmental
Investigations
Pennoni Associates, Inc. (2004), “Remedial Investigation Report”
Enviroscan, Inc. (2004), www.enviroscan.com
QUESTIONS?