AEPA
United States
Environmental Protection
Agency
Municipal Environmental Research
Laboratory
Cincinnati OH 45268
FPA 600 2-78 096
May 1978
Research and Development
Chemical and
Physical Effects of
Municipal Landfills
on Underlying Soils
and Groundwater
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate turther development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3 Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution sources to meet environmental quality standards.
This document is.available to the public through the National Technical Informa-
tion Service, Springfield,, Virginia: 22.161.
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EPA-600/2-78-096
May 1978
CHEMICAL AND PHYSICAL EFFECTS OF MUNICIPAL LANDFILLS
ON UNDERLYING SOILS AND GROUNDWATER
by
Environmental Effects Laboratory
U.S. Army Engineer Waterways Experiment Station
Vicksburg, Mississippi 39180
Interagency Agreement No. EPA-IAG-D4-0569
Project Officer
Robert E. Landreth
Solid and Hazardous Waste Research Division
Municipal Environmental Research Laboratory
Cincinnati, Ohio 45268
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
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DISCLAIMER
This report has been reviewed by the Municipal Environmental Research
Laboratory, U. S. Environmental Protection Agency, and approved for publica-
tion. Approval does not signify that the contents necessarily reflect the
views and policies of the U. S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute endorsement or
recommendation for use.
ii
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FOREWORD
The Environmental Protection Agency was created because of increasing
public and government concern about the dangers of pollution to the health
and welfare of the American people. Noxious air, foul water, and spoiled
land are tragic testimony to the deterioration of our natural environment.
The complexity of that environment and the interplay between its components
require a concentrated and integrated attack on the problem.
Research and development is that necessary first step in problem sol-
ution and it involves defining the problem, measuring its impact, and search-
ing for solutions. The Municipal Environmental Research Laboratory develops
new and improved technology and systems for the prevention, treatment, and
management of wastewater and solid and hazardous waste pollutant discharges
from municipal and community sources, for the preservation and treatment of
public drinking water supplies, and to minimize the adverse economic, social,
health, and aesthetic effects of pollution. This publication is one of the
products of that research; a most vital communications link between the
researcher and the user community.
This report presents results from the field investigation of three munic-
ipal solid waste landfill sites to determine their effects on surrounding
soils and groundwater. It provides basic data on the potential pollution
from land disposal of municipal solid waste and will add to the knowledge re-
quired to determine the environmental consequences of the land as a rector of
waste materials.
Francis T. Mayo, Director
Municipal Environmental Research
Laboratory
iii
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ABSTRACT
Three municipal landfill sites in the eastern and central United States
were studied to determine the effects of the disposal facilities on surround-
ing soils and groundwater. Borings were made up the groundwater gradient,
down the groundwater gradient and through the landfill. Soil and groundwater
samples from the test borings were examined. Groundwater samples were ana-
lyzed chemically. Soil samples were tested physically and distilled water
extracts and nitric acid digests of the soils were analyzed chemically.
Groundwater samples from under and downgradient from the landfill showed
elevated levels of sulfate in every case. At some sites increased levels of
nitrate, total organic carbon and cyanide could be related to the presence
of the landfill.
No changes in physical characteristics could be related to the presence
of the landfill at any site. No evidence was found in this study to indicate
that sub-landfill soils seal themselves.
Distilled water extracts prepared from soil samples showed consistently
low levels for all soluble constituents. Generally, there was more sulfate,
chloride, organic carbon, nitrate and higher levels of trace metals in
extracts of soils from under the landfill than from soils collected at similar
depths outside the landfill.
Nitric acid digests of soil samples showed great variability in chemical
composition. At two of the three sites; iron, manganese, boron, beryllium
and zinc were found in higher concentrations in nitric acid digests immedi-
ately under the landfill.
The results of this investigation indicate that chemical characteristics;
but, not physical characteristics were altered in sub-landfill soils. Removal
of pollutants from leachate through the action of soil was observed for only
a very limited number of pollutants.
This report was submitted in partial fulfillment of Interagency Agree-
ment Number EPA-IAG-D4-0569 by the U. S. Army Engineer Waterways Experiment
Station under the sponsorship of the U. S. Environmental Protection Agency.
This report covers the period from June 1975 to December 1977.
iv
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CONTENTS
Foreword ill
Abstract iv
Figures vi
Tables ix
Acknowledgment xiii
1. Introduction 1
2. Conclusions 7
3. Recommendations 9
4. Methods and Materials 10
Site selection 10
Sampling procedures 13
Sample handling and preparation techniques . 16
Physical testing methods 21
Chemical analytical methods 22
5. Results and Discussion 26
Physical testing 26
Chemical analyses of groundwater 31
Chemical analyses of distilled water extracts . 36
Chemical analyses of nitric acid extracts 68
Discussion 95
References 102
Appendices 104
A. Sub-surface information for Site A 104
B. Sub-surface information for Site B 117
C. Sub-surface information for Site C 128
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FIGURES
Number Page
1 Sketch of typical landfill showing sampling plan 3
2 Sketch of HvorsleV sampler 14
3 Sketch of split spoon sampler 15
4 Topographic map of site A 17
5 Topographic map of site B 18
6 Topographic map of site C 19
7 Variation of total organic carbon (TOG) concentration in
distilled water extracts of soil/sediment samples with
elevation in boring 1 at site A 51
8 Variation of sodium concentration in distilled water extracts
of soil/sediment samples with elevation in borings 2, 6, and
7 at site A 52
9 Variation of cyanide concentration in distilled water extracts
of soil/sediment samples with elevation in boring 3 at
site B 53
10 Variation in total organic carbon (TOC) concentration in
distilled water extracts of soil/sediment samples with
elevation in borings 2, 3, and 6 at site B 54
11 Variation of calcium concentration in distilled water extracts
of soil/sediment samples with elevation in borings 3, 5, and
6 at site B 55
12 Variation of iron concentration in distilled water extracts of
soil/sediment samples with elevation in boring 2 at site B , 56
13 Variation of sodium concentration in distilled water extracts
of soil/sediment samples with elevation in borings 2, 3, and
5 at site B 57
14 Variation of boron concentration in distilled water extracts of
soil/sediment samples with elevation in boring 2 at site B . 58
vi
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Number Page
15 Variation of chromium concentration in distilled water extracts
of soil/sediment samples with elevation in boring 2 at
site B 59
16 Variation of zinc concentration in distilled water extracts of
soil/sediment samples with elevation in boring 2 at site B . 60
17 Variation of calcium concentration in distilled water extracts
of soil/sediment samples with elevation in borings 1, 2, and
9 at site C 61
18 Variation of zinc concentration in distilled water extracts of
soil/sediment samples with elevation in boring 1 at site C . 62
19 Horizontal variation in chemical composition of distilled
water extracts at site A 65
20 Horizontal variation in chemical composition of distilled water
extracts at site B 66
21 Horizontal variation in chemical composition of distilled water
extracts at site C 67
22 Variation of boron concentration in nitric acid digests of
soil/sediment samples with elevation in borings 1, 2, and 6
at site A 81
23 Variation of beryllium concentration in nitric acid digests of
soil/sediment samples with elevation in boring 3 at site A . 82
24 Variation of selenium concentration in nitric acid digests of
soil/sediment samples with elevation in borings 3 and 6 at
site A 83
25 Variation of arsenic concentration in nitric acid digests of
soil/sediment samples with elevation in borings 2, 3, and 5
at site B 84
26 Variation of copper concentration in nitric acid digests of
soil/sediment samples with elevation in borings 2 and 5 at
site B 85
27 Variation in manganese concentration in nitric acid digests of
soil/sediment samples with elevation in borings 2, 3, and 5
at site B 86
28 Variation of lead concentration in nitric acid digests of
soil/sediment samples with elevation in borings 2 and 3 at
site B 87
vii
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Number
29 Variation of zinc concentration in nitric acid digests of soil/
sediment samples with elevation in borings 2, 3, and 5 at
site B 88
30 Variation of beryllium concentration in nitric acid digests of
soil/sediment samples with elevation in boring 2 at site C . . 89
31 Variation of iron concentration in nitric acid digests of soil/
sediment samples with elevation in boring 1 at site C . . . . 90
32 Variation in manganese concentration in nitric acid digests of
soil/sediment samples with elevation in borings 1 and 3 at
site C 91
33 Variation of nickel concentration in nitric acid digests of
soil/sediment samples with elevation in borings 1, 6, and 9
at site C 92
34 Variation of zinc concentration in nitric acid digests of soil/
sediment samples with elevation in borings 1, 2, 3, 6, and
9 at site C 93
35 Horizontal variation in chemical composition of nitric acid
digests at site A 96
36 Horizontal variation in chemical composition of nitric acid
digests at site B 97
37 Horizontal variation in chemical composition of nitric acid
digests at site C 98
A-l Water table map of site A 105
B-l Water table map of site B 118
C-l Water table map of site C 129
viii
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TABLES
Number Page
1 Chemical Constituents Analytically Determined in Groundwater
Filtrates, Distilled Water Extracts and Nitric Acid Digests . . 5
2 Summary of the Characteristics of the Three Sites Selected
for Study 11
3 Character of Waste Deposited in Landfill at Site A as Listed by
the Municipality 12
4 Methods of Preservation of Water Extracts and Filtered Ground-
water Subsamples for Chemical Analysis 20
5 Descriptions of USCS Soil Groups 23
6 Techniques Used in the Analysis of Distilled Water Extracts,
Nitric Acid Digests and Groundwater Filtrates 24
7 Physical Testing Data for Samples from Site A 27
8 Physical Testing Data for Samples from Site B 28
9 Physical Testing Data for Samples from Site C 29
10 Comparison of the Physical Properties of the Uppermost Samples
Collected Within and Outside the Landfills 30
11 Chemical Composition of Groundwater Obtained from Borings at
Landfill A " 32
12 Chemical Composition of Groundwater Obtained from Borings at
Landfill B 33
13 Chemical Composition of Groundwater Obtained from Borings at
Landfill C 34
14 Results of Analysis of Variance for Groundwater Chemistry .... 35
15 Analyses of Distilled Water Extracts of Soil Samples from
Experimental Borings at Site A 38
ix
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Number „
Page
16 Analyses of Distilled Water Extracts of Soil Samples from
Control Borings at Site A 40
17 *"£«; CV}8i11«led Water ^tracts °f Soil Samples from
Experimental Borings at Site B ....... . m 41
18 Analyses of Distilled Water Extracts of Soil Samples from
Control Borings at Site B ...... 42
19
20 iosc c::. o.s?mpl?s ,f- ... 44
21 Ra °n Dlstill<* Water Extracts of
? ^dmi? ?^ ^ <«^ . ,5
22 C°£;Sas±^f ^ff1 tnalySeS °f DlstiHed Water Extracts of
Soil Samples with Sample Elevation at Site A ........ 48
23 Sois T nalySeS °f ^tilled Water Extracts of
Soil Samples with Sample Elevation at Site B ........ 49
24 Correlation of Chemical Analyses of Distilled Water Extracts of
Soil Samples with Sample Elevation at Site C . . 50
25
26 natue o ^es <™ C-rol
********"•••••*•»•»• '
27 AI1S.^tS11^^^v^8^ f3!^6? !r?m ...... 72
28 ^riSsit^iteV?" ?ige:t? :f.s?^ f^ fr?m.c?— \ . 73
29 Analyses of Nitric Acid Digests of Soil Samples from
Experimental Borings at Site C ..... 74
30 Analyses of Nitric Acid Digests of Soil Samples from Control
Borings at Site C ......... c
31 Results of Randomization Test on Nitric Acid Digests of Soil
Samples Directly Under the Landfills and at Comparable Depths
Outside the Landfills ....... F
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Number Page
32 Correlation of Chemical Analyses of Nitric Acid Digests of
Soil Samples with Sample Elevation at Site A 78
33 Correlation of Chemical Analyses of Nitric Acid Digests of
Soil Samples with Sample Elevation at Site B 79
34 Correlation of Chemical Analyses of Nitric Acid Digests of
Soil Samples with Sample Elevation at Site C 80
35 Comparison of Average Chemical Composition of Groundwater and
Soil Samples from Experimental and Control Borings for
all Sites 100
A-l Log of Boring 1 at Site A 106
A-2 Log of Boring 2 at Site A 107
A-3 Log of Boring 3 at Site A 108
A-4 Log of Boring 4 at Site A 109
A-5 Log of Boring 5 at Site A 110
A-6 Log of Boring 6 at Site A Ill
A-7 Log of Boring 7 at Site A 112
A-8 Log of Boring 8 at Site A 113
A-9 List of Samples Examined from Site A 114
B-l Log of Boring 1 at Site B 119
B-2 Log of Boring 2 at Site B 120
B-3 Log of Boring 3 at Site B 121
B-4 Log of Boring 4 at Site B 122
B-5 Log of Boring 5 at Site B 123
B-6 Log of Boring 6 at Site B 124
B-7 Log of Boring 7 at Site B 125
B-8 Log of Boring 8 at Site B 126 .
B-9 List of Samples Examined from Site B 127
C-l Log of Boring 1 at Site C 130
xi
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Number Page
C-2 Log of Boring 2 at Site C 131
C-3 Log of Boring 3 at Site C 132
C-4 Log of Boring 4 at Site C 133
C-5 Log of Boring 5 at Site C 134
C-6 Log of Boring 6 at Site C ,. 135
C-7 Log of Boring 7 at Site C 136
C-8 Log of Boring 8 at Site C 137
C-9 Log of Boring 9 at Site C 138
C-10 List of Samples Examined from Site C 139
xii
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ACKNOWLEDGEMENTS
This field investigation was conducted by the Environmental Effects
Laboratory and the Soils and Pavements Laboratory of the U. S. Army Engineer
Waterways Experiment Station (WES) under sponsorship of the Municipal Environ-
mental Research Laboratory, Environmental Protection Agency.
The coordinating author was Dr. Philip G. Malone. The authors included
Dr. Bobby L. Folsom, Mr. James M. Brannon, Mr. John H. Shamburger, and
Mr. Jerald D. Broughton. Significant technical input and advice were provided
by Mr. Richard B. Mercer, Dr. Jerome L. Mahloch, Mr. Douglas W. Thompson, and
Dr. Larry W. Jones. The project was conducted under the general supervision
of Dr. John Harrison, Chief, Environmental Effects Laboratory, Dr. Rex Eley,
Chief, Ecosystem Research and Simulation Division, Mr. Andrew J. Green, Chief,
Environmental Engineering Division and Mr. Norman R. Francingues, Chief, Treat-
ment Processes Research Branch.
The guidance and support of Mr. Robert E. Landreth, Mr. Norbert B. Schomaker,
and the Solid and Hazardous Waste Research Division, Municipal Environmental
Research Laboratory, U. S. Environmental Protection Agency are gratefully
acknowledged. The Soils and Pavements Laboratory performed the physical
testing under the direction of Mr. G. P. Hale. The Analytical Laboratory
Group performed the chemical analyses under the direction of Mr. James D.
Westhoff, Dr. Donald W. Rathburn and Mr. Jerry W. Jones. The diligent
and patient efforts of Ms. Rosie Lott and Ms. Cherry Shaler, typists, and
Mr. Jack Dildine, senior graphics coordinator, are gratefully acknowledged.
Directors of WES during the course of this study were COL G. H. Hilt, CE, and
COL J. L. Cannon, CE. Technical Director was Mr. F. R. Brown.
xiii
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SECTION 1
INTRODUCTION
Disposal on land is the oldest method of municipal solid waste disposal
and is still the most widely used system. Over 90% of all municipal wastes
are currently disposed of on land in open dumps or sanitary landfills. The
sanitary landfill with systematic deposition, compaction and burial of refuse
emerged in the 1930's as the safest, least objectionable system of land-based
disposal. Some 1,400 cities are currently using landfills to dispose of some
318 thousand metric tons per day of solid wastes. The expenditure of money
on solid waste disposal is surpassed only by that spent on schools and roads
in most municipal budgets(1).
The disposition of solid wastes in landfills carries the inherent poten-
tial for degrading the quality of groundwater in the area of the landfill.
There are numerous examples of municipal landfills producing groundwater
pollution. Garland and Mosher(2) have cited several examples where the
pollution from landfills could be detected; including one case where effects
could be observed at a distance of 3 kilometers due to high selenium values
in groundwater samples. Exler(3) reported that a landfill in Germany had a
groundwater pollution plume that was also detectable for a distance of 3
kilometers down the flow gradient from the fill. The polluted groundwater in
this case showed high levels of chloride and dissolved organic material.
The pollution of groundwater by landfills has in some cases caused severe
degradation of drinking water supplies to the extent that such water is no
longer potable. Incidences of pollution of this sort cause grave economic
hardship on local governments that must attempt to relieve the pollution prob-
lem or provide a new water supply.
Some landfills are designed to contain all contaminants, but many allow
the slow downward leakage of water that has come in contact with the buried
refuse. This latter design anticipates the removal of undesirable materials
in this leachate either by filtration through or adsorption onto the earth
materials between the bottom of the landfill and the water table. This puri-
fication process is referred to as attenuation. The attenuated leachate that
does reach the water table is then diluted by the much larger quantity of
groundwater into which it flows. Groundwater pollution occurs when this
filtration, adsorption and dilution process does not operate successfully.
Although some prediction of attenuation properties can be made from soil
characteristics, such as clay content, particle size distribution, cation
exchange capacity, etc., there is no conclusive method for verifying that
attenuation is not effective until groundwater pollution is observed. The
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soil beneath a landfill should show an increase in contaminants if attenuation
is occurring. Therefore, the examination of earth materials beneath sanitary
landfills should be a useful technique for gauging the extent of pollutant
attenuation.
The objectives of the present investigation are to examine three landfills
that are situated in widely different geological circumstances in order to:
a) discover if changes have occurred in the chemical characteristics of
local groundwater because of landfill operation,
b) determine the influence of the landfilled refuse on the chemical
characteristics and physical properties of the geologic materials
directly below the landfill,
c) determine if chemical constituents that are present in the soil below
the landfill can be released into contacting water,
d) establish if a relationship exists between the depth below the refuse
and the chemical and physical properties of the earth materials, and
e) discover if any physical or chemical characteristics of the material
beneath a landfill can be used to predict the extent of contaminant
attenuation.
To meet these objectives, an idealized concept or model (Figure 1) for
leachate movement and attenuation was developed to provide a rationale for the
sampling program. In this model the rainwater falling on the landfill satu-
rates the refuse and then percolates through the soil directly below. A
variable portion of the filterable and exchangeable material in the leachate
is deposited in the soil below the landfill. This attenuated leachate con-
tinues downward into the water table. Groundwater flowing under the landfill
dilutes the leachate and carries the pollutants in a plume down the ground-
water gradient. Based on this idealized model, borings were located in such
a way as to produce:
a) groundwater from wells beneath the landfill and from wells located
both up and down the groundwater flow gradient in the area of the
landfill,
b) samples of soil from beneath the landfill and from comparable depths
outside the landfill,
c) soil samples collected at different levels down the boreholes both
outside and beneath the landfill, and
d) samples collected near the top of the saturated zone (water table)
around and inside the landfill.
Physical testing of soil samples collected below the landfill and at
comparable depths outside the landfill was undertaken to evaluate changes
related to the buried refuse. The physical characterization included percent
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Figure 1. Sketch of typical landfill showing sampling plan. The updip
control holes show background levels. The experimental wells
and downdip control holes show contaminant movement from the
landfill. Bold arrows indicate direction of groundwater
movement.
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moisture, dry density, grain size distribution, permeability and soil class-
ification. Randomization was used to test for significant differences in
physical properties. Vertical variability in selected bore holes was also
evaluated. The small sample sizes did not allow the use of statistical tests.
The samples of groundwater collected in this study were used to indicate
loss of contaminants from the landfill or the soil beneath the landfill into
the local groundwater. If contaminants are moving to the water table, their
concentrations should be higher beneath and downdip from the landfill. A
list of analyses run is given in Table 1. A one-way analysis of variance
technique was employed to assess the significance of changes in water quality.
Soil samples from beneath the landfill and from comparable depths outside
the landfill were treated in two ways: One aliquot of soil was extracted with
distilled water to remove all ions that could be dislodged by water alone. A
list of analyses run is given in Table 1. The distilled water extract gives
a rate of release of material from the soil into the surrounding water. The
water extract is assumed to represent the maximum concentration available in
water contacting the soil, not the maximum, total amount capable of being
leached from the soil. The distilled water leach then indicates the mobility
of various ions being held in the soil. The most effective attenuation is
occurring when the soil beneath the landfill shows an ability to accumulate
a contaminant and to release the contaminant at a very slow rate. A
randomization technique was used to test the significance of differences
observed in the composition of the distilled water extracts of soil samples
collected directly beneath the landfill and samples collected at comparable
depth outside the landfill. The significant results of the randomization
test point out those elements at each site whose mobility in aqueous solution
is effected by material from the landfill. A second aliquot of fresh soil
was digested with hot, 8N nitric acid to bring all ions not bound into sili-
cate lattices into solution. A list of analyses run is also given in Table 1.
This digest represents the total of all materials that could potentially be
leached from the soil under the most severe conditions. Since it is assumed
that there is no lateral movement of leachate above the water table, differ-
ences in composition between digests of these samples can be interpreted as
the loss or gain of material in the soil due to the presence of the landfill.
A randomization technique was used to test for significant differences in
composition between acid digests of soil samples collected directly below the
landfill and samples collected at comparable depths (and above the water
table) outside the landfill. The significant results from the randomization
tests point out those elements at each site that are being added to the soil
or removed from the soil by the movement of leachate from the landfill.
If the soil beneath the landfill is being altered by leachate from the
landfill, any change should be most pronounced directly beneath the refuse
and the magnitude of this change should decrease with depth. Samples of soil
were taken at intervals down the boreholes to determine if any correlation
between the concentration of materials in the soil and depth (or sample
elevation) could be observed. Correlation with sample elevation was only
attempted with those elements that had shown a significant contrast in con-
centrations available under and away from the landfill at each site. A
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TABLE 1. CHEMICAL CONSTITUENTS ANALYTICALLY DETERMINED IN GROUNDWATER
FILTRATES, DISTILLED WATER EXTRACTS, AND NITRIC ACID DIGESTS
Constituent
S°4
S°3
Cl
NO -N
N02-N
CN
TOC
Ca
Fe
Mg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
Groundwater
filtrate
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Water
extract
of soil samples
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Nitric acid
digests
of soil samples
—
—
—
—
—
—
—
—
X
—
X
—
X
X
X
X
X
X
X
X
X
X
X
— = Not determined.
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Spearman rank correlation technique was employed. The correlation technique
made it possible to see if consistent relationships could be observed between
sample elevation and sample composition in borings made inside and outside
the landfill.
Samples of soil collected near the top of the saturated zone both outside
and inside the landfill were examined to see if any effects of lateral move-
ment of leachate could be observed. Distilled water leaches and nitric acid
digests of these soil samples were analyzed. Plots of analyses were prepared
to assess any changes in constituents that could be related to the presence
of the landfill. No attempt was made to evaluate these analyses statistically
because of the small sample sizes involved.
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SECTION 2
CONCLUSIONS
At all three municipal landfill sites, changes in the chemical composi-
tion of the groundwater could be related to the position of the borings with
respect to the landfill. Water quality below and down the groundwater flow
gradients from the landfills showed increased sulfate levels in every case.
At several sites increased nitrate, total organic carbon, and cyanide levels
could be related to the presence of the landfill.
No changes in physical parameters measured in soil samples in this study
could be related to the effect of the landfill. No consistent alterations
in dry density, water content, permeability, or percent fines could be related
to the position of soil samples with respect to the landfill. Physical char-
acteristics of sub-landfill soil samples as measured by standard engineering
techniques were not significantly different from samples collected at com-
parable depth outside the landfill. No consistent vertical changes in soil
physical characteristics in borings through the landfill could be detected.
The percolation of leachate did not alter the permeability of the soil beneath
the refuse. No evidence was found in this study to substantiate the idea that
sub-landfill soils seal themselves.
Distilled water extracts prepared from soil samples showed all soluble
constituents were present in very small quantities. Many variations observed
were not consistent from one site to another. In general, there was more
leachable sulfate, chloride, organic carbon, nitrate and more available trace
metals in soil from under the landfills than in soils from similar depths
outside the landfill. Calcium, iron and zinc were the only metals that showed
decreased availability under any of the landfills. The lack of water-
extractable iron under the landfill at the one actively operating site was
probably due to its precipitation"as an insoluble compound such as sulfide.
In another series of distilled water extracts, many constituents showed de-
creasing availability with increasing sample depth in borings below the land-
fill, suggesting their source was the refuse in the landfill. Calcium and
zinc were exceptions to this trend and showed increasing levels in distilled
water extracts with increasing depth. This trend may be due to removal by
leaching by organic acids from the refuse (especially in the case of calcium)
or the formation of insoluble compounds under the landfill.
Analyses of distilled water extracts of soil samples taken from near the
water table shows that the maximum concentration of many constituents as
measured in the water extract can be displaced down the groundwater gradient
from the landfill. Displacement of the concentration maxima was noted with
nitrate, organic carbon, calcium, iron, magnesium, manganese, sodium and boron.
7
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Nitric acid digests of soil show great variability in chemical composition.
At two sites iron, manganese, boron, beryllium and zinc were found in higher
concentrations in nitric acid digests from immediately under the landfill than
at comparable depths outside the landfill. This suggests that these metals
are being added to the soil under the landfill (i.e. attenuated). Only arsenic
showed a decreased level under the landfills suggesting it was being mobilized
or leached from the sub-landfill soil.
Analyses of nitric acid digests from soil samples collected at increasing
depth below the landfill indicate that iron, manganese, arsenic, boron,
beryllium, lead, selenium and zinc (at site B) are accumulating in soil imme-
diately beneath the landfill. Only two metals, nickel and zinc (at site C),
showed an increasing abundance with increasing depth indicating these metals
are leaching out of the upper layers of sub-landfill soil.
Analyses of nitric acid digests of soil samples taken from near the water
table also show that the maximum concentration of some of the landfill con-
stituents can be displaced down the groundwater gradient from the landfill.
This trend was noted for the maximum concentrations of arsenic, manganese,
copper and lead.
The results of this investigation indicate that chemical characteristics,
but not physical characteristics, were altered in soil under the landfill, and
chemical changes in the sub-landfill soil can be related to the capacity of
the soil to filter, absorb or precipitate the contaminants from the refuse.
Instances were noted where the leachate added material to the soil and also
mobilized normal soil constituents to effect changes in soil composition.
-------
SECTION 3
RECOMMENDATIONS
The interaction between leachate from municipal refuse and soil is com-
plex varying with the character of the soil and the composition of the
leachate. The chemical character of the soil is itself changed as material is
added or leached out. The landfill leachate varies with the nature of the
refuse disposed and the type of decomposition occurring. The results of this
survey indicate that significant chemical changes occur in the soil that can
be related to the attenuation process.
Future investigations should include characterization of the landfill
leachate before and after contact with the soil as well as analysis of acid
digests of the soil. Any future study of sub-landfill soils should include
soil variables such as mineralogy, cation exchange capacity, and slurry pH.
Any continued work on leachate-soil interaction could include following soil
changes through several annual cycles until stabilization of the refuse
occurs. Further physical testing should be undertaken on a very fine scale,
carefully including the soil-refuse interface.
Field investigations of this nature while involving many variables, re-
present the best approach to the understanding of how attenuation processes
operate and their effect on groundwater quality. Continued work of this type
may allow us to predict and overcome the hazard to groundwater resources
involved in landfill disposal.
-------
SECTION 4
METHODS AND MATERIALS
SITE SELECTION
Three municipal landfills were selected from widely different geographic
areas in the Eastern United States. All sites were selected from areas where
rainfall and infiltration rates were sufficient to produce an abundance of
leachate. A summary of the important engineering and geologic characteris-
tics of each of the sites selected for this survey is given in Table 2. The
sites are designated only by letter.
Two principal factors effecting the character of the contaminants leaving
a landfill are the nature of waste buried, and the age of material in the
site. Other factors that impinge on the problem of the character of leachate
from a landfill are oxidation-reduction conditions in the landfill, temper-
ature in the landfill, and dilution of the leachate by local groundwater flow.
The exact type and amount of waste material deposited in each site is difficult
to determine, especially if the landfill has been completed and closed. Only
in the case of site A is there a reasonably complete listing of wastes avail-
able from the local Department of Public Works (Table 3). Note that several
types of industrial wastes have gone into this site including wastes from local
rubber manufacturing, meat packing and paper mill operations. The information
regarding the nature of waste placed at site B is not available. The waste is
thought to be largely municipal (household and commercial) with only minor
industrial input since there are no large manufacturing operations in the area
served by the landfill. No waste survey is available for site C; but,
engineering reports associated with the project state that the site received
900 tons per day of commercial and household refuse and 200 tons per day of
incinerator ash. This site also received a great deal of sewage sludge and
has been top-dressed with this material.
Sanitary landfill leachate typically changes in composition as the mater-
ial in the landfill degrades (4,5) therefore the age of the landfill is an
important consideration. Site A had been officially closed for fifteen years
when the samples for this study were collected. However, there was some
evidence of recent, unauthorized use of the site as an open dump for household
refuse. The refuse was originally placed in trenches and was not compacted.
Differential settling produced a series of shallow gullies where the trenches
had been dug. The municipality later filled in the depressions with sewage
sludge. At site B, the landfill was completed in 1972, and then regraded to
produce a recreation area. The regrading included exposing and reburying part
10
-------
TABLE 2. SUMMARY OF THE CHARACTERISTICS OF THE THREE SITES SELECTED FOR STUDY
Characteristic
Site A
Site B
Site C
Geographic area within North Central
the U.S.
General geologic
setting
Mean annual rainfall
Mean annual air
temperature
Nature of waste
Liner used below
refuse
Thickness of refuse
observed
Thickness of unsatu-.
rated zone
Nature of material in
unsaturated zone
Average hydraulic con-
ductivity below
refuse
Average thickness of
covering material
Character of covering
material
Dates of operation of
site
Tvpe of operation
Glacial outwash
(valley train
deposits)
74 cm
8°C
Municipal and
industrial
None
4.82-6.52 m
(avg. 5.40 m)
18.23-20.24 m
(avg. 19.33 m)
Sand
1x10 cm/sec
1.65 m
Sand and gravel
1947 - 1961
Trench and fill
South Central
Wind-blown silt
and clay
(loess)
124 cm
19°C
Municipal and
industrial(?)
None
1.92-4.88 m
(avg. 3.08 m)
0.91-3.51 m
(avg. 2.47 m)
Clayey silt
East Central
Deeply weathered
residual soil
(metamorphic
terrane)
104 cm
13°C
Municipal and
industrial(?)
None
14.02-24.70 m
(avg. 19.45 m)
0.91-10.88 m
(avg. 4.79 m)
Silty sand
7.3x10 cm/sec 2.9x10 cm/sec
0.09 m
Clay
1959 - 1972
Surface fill
0.82 m
Clay
1964 - present
Surface fill
11
-------
TABLE 3. CHARACTER OF WASTE DEPOSITED IN LANDFILL AT SITE A AS LISTED
BY THE MUNICIPALITY
Mixed demolition refuse
Sand
Dirt
Gravel
Rock
Broken pavement
Construction materials
Household refuse
Domestic garbage and kitchen wastes
Domestic incinerator residue
Cans and glass bottles
Furniture and carpets
Major appliances
Yard refuse
Logs
Grass and garden clippings
Brush
Chipped limbs and leaves
Commercial refuse
Used tires
Mixed commercial trash
Kitchen wastes
Commercial incinerator residue
Scrap metal
Wood crates
Industrial wastes
Rubber manufacturing wastes
Rubber scrap
Liquid and wet chemical waste
Paper mill sludge
Oil, tar and asphalt
Meat packing waste
Paunch
Manure
Sewage grit
Sewage sludge
12
-------
of the refuse and compacting the landfill prior to partial paving with asphalt.
The regrading took place only a year before this investigation. Site C was
still receiving wastes; but, the portion where two of the borings (1 and 2)
were placed had been closed from one to three years at the time of sampling.
All of the sites selected had been in place long enough to have possibly
effected the groundwater and soil beneath and around the landfill (see
Table 2). All of the sites contain domestic and commercial wastes; but only
site A has received a major amount of industrial waste. These landfills were
chosen because they have many factors in common with other landfills in the
Eastern United States. All contain mixed residential and commercial refuse
buried using prevailing landfilling methods.
SAMPLING PROCEDURES
A general sampling plan for all sites was generated using the theoretical
model as described above (Figure 1) and then modified to fit the requirements
at the individual sites. The general sampling scheme called for six or more
holes to be bored at each landfill: a minimum of two holes to be bored
through the buried refuse and five to six holes to be bored outside the land-
fill. This sampling pattern allowed comparison between typical, uneffected
groundwater and soil, and groundwater and soil which was in contact with
leachate draining from the buried refuse.
All sampling was done with a truck-mounted, rotary drill using 16.8 cm OD
hollow-stem auger. The auger with a central plug in place was drilled in to
the desired depth. The central plug was removed and a Hvorslev fixed-piston
sampler (Figure 2) or a split spoon sampler (Figure 3) was pressed into the
sediment or soil directly below the end of the auger using the hydraulic
cylinders on the drill rig. In this way an undisturbed soil or sediment
sample was obtained. The split spoon sampler was only used in cases where
objects were encountered in the subsurface that could not be penetrated by the
thin-walled tube (Shelby tube) on the Hvorslev sampler.
The vertical distribution of soil/sediment samples collected down the
hole was arranged in a way to maximize the probability of collecting samples
at two critical points in the boring: the refuse-soil interface, and the top
of the saturated zone. Since the strongest effects of leachate on the subfill
material should occur directly below the refuse, a sample was always taken at
the depth predicted by the landfill design as being the combined thickness of
the refuse and cover. Sampling then continued at closely spaced intervals
down the hole. The top of the water-saturated zone was predicted from water
table measurements that had been recorded for other wells in the area. A
series of closely spaced samples was taken in this interval. The holes were
allowed to remain open for two to three days with the auger flights in place.
These auger flights served as a temporary well casing to prevent seepage from
the surface from entering the well. Groundwater samples were obtained from
the temporary wells by lowering a bailer into the top of the hollow stem
auger. After a groundwater sample was obtained the auger was removed and
the holes were backfilled with cement and/or bentonite to a point well above
the water table. The filling was then completed with well cuttings. This
13
-------
r
L 754 J
SAMPLER
HEAD
94.49
cm
VACUUM
BREAKER ROD
BARREL
PISTON TOP
PISTON BASE
Figure 2. Sketch of Hvorslev Sampler
-------
HEAD
SOLID OR SPLIT
BARREL
SHOE
QD. 5.08cm, 635cm, 7.62cm, or 8B9cm
I.D. 3Blcm,5.08cm,6.35cm,or 7.62cm
Figure 3. Sketch of split spoon sampler.
15
-------
was done to assure that a well would not provide a conduit for flow of poll-
uted water to the water table.
The locations of all borings at each landfill site are given in Figures
4-6. Arrows in these figures indicate the most probable direction of ground-
water flow deduced from water level maps (Figures A-l, B-l, C-l in appendices)
and chemical data. The descriptive well logs are presented in the appendices
(Tables A-1--A-8, B-l—B-8, C-l—C-9). Tables A-9, B-9, and C-10 list all soil/
sediment samples examined from each boring giving their elevation and other
relevant data.
SAMPLE HANDLING AND PREPARATION TECHNIQUES
Two different types of soil samples were collected in the boring program:
samples for physical testing and samples for chemical analysis. Groundwater
samples were also taken from each well for chemical analysis. The set of
samples obtained for physical testing was used to determine soil class under
the unified soil classification system (6), dry density, grain-size distribu-
tion, water content and permeability. These physical parameters were determined
using standard engineering test procedures. This sample set was collected
without disturbing the soil more than necessary. All physical testing samples
were carefully packaged and sealed in coring tubes to retain the original
moisture content and sample texture during transportation.
Depth to groundwater was measured with a chalked, steel tape at each
boring. All of the groundwater samples were collected from the borings by
bailing the water from the center of the hollow stem auger using a bailer made
from small diameter tubing. The groundwater was transferred to polyethylene
bottles which were labelled and packed in an insulated chest filled with
crushed ice. The samples were stored under refrigeration and kept tightly
capped until they were prepared for chemical analysis. The preparation con-
sisted of centrifuging each sample at 2200 rpm for 30 minutes. The resulting
supernatant was membrane-filtered through a 0.45 nm filter and split into five
subsamples which were preserved as shown in Table 4.
Samples of soil for chemical analysis were collected simultaneously with
the samples for physical testing; but, no attempt was made to maintain the
soil in an undisturbed condition. Each sample was removed from the sampler,
placed in a wide-mouthed polyethylene bottle, labelled, and packed in an ice-
filled chest. These soil samples were refrigerated during all subsequent
transportation and/or storage. Two extracts were made from each soil sample:
one with distilled water and one with 8N nitric acid. The material that could
be easily leached out with distilled water was considered transient and would
readily be leached from the soil by dissolution in rainwater. The nitric
acid leach would contain the transient materials and also all of the material
that could be solubilized by a strong, oxidizing acid. Those elements present
as carbonates or sulfides, or adsorbed to clay minerals, to iron oxide or to
insoluble organic materials would be freed (7,8). Elements in non-clay sili-
cate lattices would be leached only to a minor degree (9).
16
-------
X- LIMIT OF LANDFILL
(APPROXIMATE)
NOTE: ARROWS INDICATE MOST PROBABLE GROUND WATER GRADIENT BASED
ON WATER TABLE MEASUREMENTS AND CHEMICAL ANALYSES.
Figure 4. Topographic map of site A (contour lines are in feet above mean sea level). 0.305 m = 1 ft.
-------
CD
100
NOTE: ARROWS INDICATE MOST PROBABLE GROUND WATER GRADIENT BASED
ON WATER TABLE MEASUREMENTS AND CHEMICAL ANALYSES.
Figure 5. Topographic map of site B (contour lines are in, feet above mean sea level). 0.305 m = 1 ft.
-------
WELL LOCATION
X- LIMIT OF LANDFILL
SCALE
500 0 5OO F T
NOTE: ARROWS INDICATE MOST PROBABLE GROUND WATER GRADIENT BASED
ON WATER TABLE MEASUREMENTS AND CHEMICAL ANALYSES.
Figure 6. Topographic map of site C (contour lines are in
feet above mean sea level). 0.305 m = 1 ft.
19
-------
TABLE 4. METHODS OF PRESERVATION OF WATER EXTRACTS AND FILTERED GROUNDWATER
SUBSAMPLES FOR CHEMICAL ANALYSIS
Chemical species to be determined
Method of preservation
, Cl,
CN
Total organic carbon
Ca, Fe, Mg, Mn, Na, As, B, Be,
Cd, Cr, Cu, Ni, Pb, Se, Zn
Hg
Refrigeration to 4°C
Sample brought to pH 11 with NaOH
Refrigeration to 4°C
Samples acidified with HC1 to pH 1
added and samples acidified with
HN03 to pH 1
20
-------
For distilled water extracts, the contents of each sample bottle was mixed
to assure a homogeneous sample. A 200-gram subsample of moist soil was weighed
out into a 1000-ml polycarbonate centrifuge bottle and six hundred ml of dis-
tilled-deionized water was added to each. The centrifuge bottles were shaken
on a rotary shaker for one hour, and then centrifuged at 2200 rpm for 30
minutes. The supernatant was filtered through a 0.45 nm membrane filter. The
filtrate was split into five subsamples for chemical analysis. The subsamples
were preserved as outlined in Table 4.
A second subsample consisting of 50 grams of moist soil was taken from
each sample bottle for nitric acid digestion. In each digestion the soil was
weighed into a 250-ml fluorocarbon beaker and 60 ml of 8N reagent grade nitric
acid was added. The soil-acid suspension was heated to 95°C for 45 minutes
and stirred every fifteen minutes. After cooling to room temperature, the
suspension was filtered through a 0.45 nm membrane filter. The digested soil
was washed in the filter three times with 20-ml portions of 8N nitric acid.
The filtrate was quantitatively transferred to a 250-ml volumetric flask and
brought up to volume with 8N nitric acid and then stored in a polyethylene
bottle. No preservation procedure was necessary.
A third subsample was taken from each sample bottle to determine the
moisture content of the soil. These moisture contents were used to correct
subsequent chemical analyses so that soil acid digests could be expressed in
milligrams per kilogram dry weight of soil.
PHYSICAL TESTING METHODS
The physical tests run on these samples included water content, sample
dry density, permeability, and grain-size analysis. Data gathered from these
tests and visual examination of the samples were used to classify the
materials into standard soil engineering categories. All testing was done
using standard soil engineering methods (10).
To determine water content, a sample taken from a sealed coring tube was
weighed into a tared sample dish, dried at 110°C and weighed periodically
until a constant weight was obtained.
Sample dry density (or dry unit weight) is the weight of oven-dried soil
per unit volume of soil. This measurement can be made in two different ways:
by trimming the soil sample into a precisely measured regular shape and drying
and weighing the trimmed sample; or, by sealing the surface of a soil specimen
with wax and measuring its volume by water displacement, then removing the
sealing material and drying and weighing the specimen. The water displacement
procedure was used with samples containing gravel or other coarse material
that prevented the sample from being trimmed accurately.
Grain-size analysis was performed by sieving the dried, disaggregated soil
through a standard sieve series. Standard hydrometer density measurements were
run on a suspension prepared from the fraction passing the 200-mesh sieve.
21
-------
Permeability measurements were made using a constant-head test system with
coarse-grained soils, and a falling-head test system with fine sands or clays.
In all cases standard procedures and equipment were employed (10).
The major characteristics (especially grain-size analyses and characteristics
of the fine fraction) of the samples were useH to classify the soils. The
classification system is summarized in Table 5. These classification categories
and symbols are used to summarize soil characteristics in the logs presented
in Tables A-l—A-8, B-l—B-8, and C-1--C-9.
CHEMICAL ANALYTICAL METHODS
The techniques used in analyzing the filtered groundwater samples, dis-
tilled water extracts and nitric acid digests are summarized in Table 6. In
all cases, the samples were run within the recommended time limits for the
storage of samples (11).
The analyses of groundwater samples is given in milligrams per liter of
filtered sample. The water extracts are also presented in milligrams per
liter of filtered extractant. The water extract represents an equilibrium or
near equilibrium solution with respect to the solid phases and the adsorbed
phases in the soil; therefore, the analytical data are presented on a solution
basis rather than a dry weight basis. The nitric acid digests are a determi-
nation of the total acid digestible fraction; therefore, the results are
presented as milligrams extracted per kilogram dry weight of soil.
22
-------
TABLE 5. DESCRIPTIONS OF USCS SOIL GROUPS (6)
Group symbol Typical group description
GW Well-graded (poorly-sorted) gravels, gravel-sand mix-
tures, little or no fines
GP Poorly-graded (well-sorted) gravels, or gravel-sand
mixtures, little or no fines
GM Silty gravels, gravel-sand-silt mixtures
GC Clayey gravels, gravel-sand-clay mixtures
SW Well-graded (poorly-sorted) sands, gravelly sands, little
or no fines
SP Poorly graded (well-sorted) sands, gravelly sands, little
or no fines
SM Silty sands, sand-silt mixtures
SC Clayey sands, sand-clay mixtures
ML Inorganic silts, very fine sands, clayey silts, low
plasticity
CL Inorganic clays, low to medium plasticity, lean clays
OL Organic silts and organic silty clays of low plasticity
MH Inorganic silts, micaceous or diatomaceous fine, sandy
or silty soils, elastic silts
CH Inorganic clays of high plasticity, fat clays
OH Organic clays of medium to high plasticity, organic silts
Pt Peat and other highly organic soils
23
-------
TABLE 6. TECHNIQUES USED IN THE ANALYSIS OF DISTILLED WATER EXTRACTS,
NITRIC ACID DIGESTS AND GROUNDWATER FILTRATES
Chemical
species
so4
so3
Cl
NO -N
NO -N
CN
TOC
Ca
Fe
Mg
Mn
Na
As
Lowest reporting*
concentration in
Procedures and/or instrumentation* (ppm)
Standard Turbidimetric Method in combination
with a Varian Model 635 Spectrophotometer
Standard Potassium lodide-Iodate Titration
method*
Standard Mercuric Nitrate Titration method
Technicon II Auto Analyzer, Industrial Method
no. 100-70W^
Same as above
Technicon II Auto-Analyzer, Industrial Method
no. 315-74W±
Determined with Envirotech Model No. DC 50
TOC Analyzer
Determined with a Spectrametrics Argon Plasma
Emmission Spectrophotometer Model II
Same as above
Same as above
Same as above
Same as above
Determined with a Gaseous Hydride System,
8
1
5
0.01
0.01
0.01
1
0.03
0.05
0.03
0.03
0.03
0.001
B
Perkin-Elmer Atomic Absorption Unit
Determined with a Spectrametrics Argon Plasma
Emission Spectrophotometer Model II
0.02
24
(continued)
-------
TABLE 6 (continued)
Chemical
species
Be
Cd
Cr
Cu
Hg
Procedures and /or instrumentation*
Same as above
Same as above
Same as above
Same as above
Determined with a Nisseisangyo Zeeman Shift
Lowest reporting
concentration in
(ppm)
0.02
0.03
0.03
0.02
0.0002
Atomic Absorption Spectrophotometer
Ni Determined with a Spectrametries Argon Plasma 0.03
Emission Spectrophotometer Model II
Pb Same as above 0.1
Se Determined with a Perkin-Elmer Heated Graphite 0.002
Atomizer Atomic Absorption Unit
Zn Determined with a Spectrametrics Argon Plasma 0.03
Emissions Spectrophotometer Model II
* Mention of trade names or commercial products does not constitute endorse-
ment or recommendation for use.
Standard Methods for the Examination of Water and Wastewater, American
Public Health Association, New York, 13th Edition, 1971.
— Technicon Industrial Systems, Tarrytown, New York.
25
-------
SECTION 5
RESULTS AND DISCUSSION
PHYSICAL TESTING
The soil parameters measured in the physical testing program are those
most likely to be effected by the infiltration of leachate from overlying
refuse. The literature indicates that the leachate suspension is filtered by
the uppermost layer of soil below the refuse (4). Filtration of the leachate
should cause the soil to show:
a) an increase in density due to the addition of fine material in inter-
granular spaces,
b) a decrease in permeability due to accumulation of fine-grained -
particles that obstruct the natural pore connections in the soil,
c) an increase in the percentage of fine silt- and clay-sized material
(less than 200-mesh grain size) due to accumulated leachate residue,
and
d) a change in water content due to the accumulation of water retaining
organic material.
A complete tabulation of data obtained from the physical testing program
is given in Tables 7, 8 and 9. A summary contrasting the physical character-
istics found in the samples from directly below the landfill and at comparable
elevations outside the landfill is given in Table 10. None of the sites show
significant differences in dry density between soil beneath and outside the
landfill. Likewise, the variation in water content shows no pattern that can
be related to the position of the sample with respect to the landfill. The
data available on permeability or hydraulic conductivity do show a signifi-
cant difference between inside (sub-refuse) and outside samples for site B.
Unfortunately, it is very difficult to obtain reliable, reproducible perme-
ability measurements from this extremely fine-grained, loess-based soil.
Laboratory experiments with reconstituted samples indicated that the perme-
ability is very dependent on the state of compaction of the material. Slight
disturbances of the samples could account for a great deal of the variation
observed or the differences might have been produced by the grading and
compaction when the completed fill was developed as a recreation area. There
is no significant difference in the weight percentage of material finer than
200-mesh for samples under and outside the landfills at any of the three sites.
If the residue from leachate is being trapped, it constitutes a very small
portion of the cored sample.
26
-------
TABLE 7. PHYSICAL TESTING DATA FOR SAMPLES FROM SITE A
Boring
no.
1
1
1
2
2
2
2
2
2
3
3
3
4
4
5
5
5
6
6
6
7
7
7
8
8
8
Sample
no.
PI
P4
P6
PI
P2
P3
P4
P5
P6
PI
P3
P5
PI
P3
PI
P3
P5
PI
P3
P5
PI
P3
P4
PI
P3
P5
Depth
(m)
7.20 -
10.94 -
22.65 -
6.25 -
6.92 -
8.81 -
13.87 -
19.51 -
24.39 -
7.86 -
10.82 -
22.25 -
3.20 -
6.25 -
4.57 -
7.62 -
18.44 -
4.72 -
7.77 -
19.00 -
4.42 -
7.77 -
13.26 -
14.32 -
17.38 -
28.65 -
7.70
11.64
22.84
6.68
7.44
9.42
14.39
19.87
24.94
8.32
11.25
22.53
3.90
6.62
5.29
8.20
18.83
5.33
8.42
19.48
4.76
8.26
13.75
15.03
17.96
28.99
Dry
density
(g/cc)
1.60
1.62
1.59
1.61
1.72
1.64
1.50
1.55
1.56
1.63
1.61
1.76
1.59
1.59
1.65
1.67
1.74
1.57
1.71
1.69
1.62
1.78
1.75
1.64
1.66
1.70
Water
content
(%)
4.1
3.1
3.9
3.6
3.3
2.9
6.7
3.8
3.8
5.2
2.5
2.4
7.5
4.0
2.8
2.9
2.7
2.8
3.2
2.9
3.3
3.1
2.9
4.5
3.4
4.2
Permeability or
hydraulic cond.
(cm/sec)
1.1 x 10~*
1.1 x 10~r
1.4 x 10
0.58 x 10"1
_n
1.1 x 10 ,
0.47 x 10":
0.76 x 10
—
0.82 x 10~?"
1.1 x io~:
1.3 x 10"1
2.0 x 10"1
—
—
—
—
—
—
—
—
—
—
Classification
Sand (SP) , brown
Sand (SP) with trace gravel, brown
Sand (SP) with trace gravel, brown
Sand (SP) with trace gravel, brown
Gravelly sand (SP) , brown
Sand (SP) with gravel, brown
Sand (SP), brown
Sand (SP) with gravel, brown
Sand (SP) with trace gravel, brown
Sand (SP) with gravel, brown
Sand (SP) with trace gravel, brown
Gravelly sand (SP) , brown
Sand (SP), brown
Sand (SP), brown
Sand (SP) with gravel, brown
Sand (SP) with gravel, brown
Sand (SP) with gravel, brown
Sand (SP) with gravel, brown
Sand (SP) with gravel, brown
Sand (SP) with gravel, brown
Sand (SP) with trace gravel, brown
Gravelly sand (SP) , brown
Sand (SP) with gravel, brown
Sand (SP) with trace gravel, brown
Sand (SP) with gravel, brown
Sand (SP) with gravel, brown
Note: — indicates no data available.
-------
to
oo
Boring
no.
Sample
no.
TABLE <*. PHYSICAL TESTING DATA FOR SAMPLES FROM SITE B
Depth
(m)
Density
(g/cc)
PI 6.25 - 6.37
P2 8.41 - 8.87 1.48
P2 3.66 - 4.15 1.57
P3 5.79 - 6.52 1.56
PI 6.10 - 6.77 1.40
Water
content
26.7
33.3
24.7
28.8
20.1
Permeability or
hydraulic cond.
(cm/sec)
,-8
8.41 x 10
-7
7.72 x 10
-5
Classification
Silt (ML) gray
7.72 x 10 Silty clay (CL) gray
Silt (ML) grayish brown
6.22 x 10~ Silt (ML) grayish brown
Silt (ML) brownish tan
P3
9.15 - 9.85
1.57
30.3
3.24 x 10
-6
Silt (ML) grayish brown
P3 4.57 - 5.27
PI 6.10 - 6.68
1.53
28.9
32.5
7.84 x 10 Silt (ML) brownish gray
Silt (ML) olive gray
Note: — indicates no data available.
-------
TABLE 9. PHYSICAL TESTING DATA FOR SAMPLES FROM SITE C
Boring
no.
1
1
2
2
3
3
4
4
6
6
7
9
Sample
no.
PI
P3
PI
P3
PI
P3
PI
P4
P2
P4
P2
P4
Depth
(m)
25
28
18
22
19
22
1
8
0
4
0
7
.91 -
.96 -
.29 -
.26 -
.97 -
.47 -
.70 -
.49 -
.91 -
.57 -
.91 -
.32 -
26.36
29.40
18.96
22.59
20.46
22.92
2.03
8.76
1.46
5.11
1.58
7.88
Dry
density
(g/cc)
1.53
1.71
1.65
1.66
1.69
1.69
1.52
1.64
1.63
1.78
1.52
1.69
Water
content
18.
17.
19.
18.
21.
18.
28.
21.
16.
14.
20.
19.
5
3
4
9
1
1
9
2
4
9
3
2
Permeability or
hydraulic cond.
(cm/sec) Classification
6.
7.
6.
2.
1.
2.
3.
5.
5.
1.
4.
1.
6 x 10"5
8 x 10"5
6 x 10"5
8 x 10
2 x 10~6
9 x 10
0 x 10"7
7 x 10"6
9 x 10
9 x 10"5
3 x 10~
7 x 10~
Sandy silt (ML), brown
Silty sand (SM) , brown
Silty sand (SM) , brown
Sandy silt (ML), brown
Clayey, sandy silt (ML),
Sandy silt (ML), brown
Clayey, sandy silt (ML) ,
Sandy silt (ML) , brown
Clayey, sandy silt (ML),
Sandy silt (ML) , brown
Sandy silt (ML), reddish
Silty sand (SM) , brown
brown
brown
tan
brown
-------
TABLE 10. COMPARISON OF THE PHYSICAL PROPERTIES OF THE UPPERMOST
SAMPLES COLLECTED WITHIN AND OUTSIDE THE LANDFILLS
Dry
Location density
Sample (inside/outside) (gm/cc)
A 1P1
A 2P1
A 3P1
A 4P1
A 5P1
A 8P1
A 6P1
A 7P1
B 1P2
B 2P2
B 6P1
B 7P3
C 1P1
C 2P1
C 3P1
C 4P1
C 6P2
C 7P2
inside
inside
inside
outside
outside
outside
outside
outside
inside
inside
outside
outside
inside
inside
outside
outside
outside
outside
1.60
1.61
1.63
1.59
1.65
1.64
1.57
1.62
1.48
1.57
1.40
1.53
1.53
1.65
1.69
1.52
1.63
1.52
Water
content
4.1
3.6
5.2
7.5
2.8
4.5
2.8
3.3
33.3
24.7
20.1
28.4
18.5
19.4
21.1
28.9
16.4
20.3
Permeability Weight %
(cm/ sec) finer than 200 mesh
1.1 x 10~J
0.58 x 10~{-
0.82 x 10
_ _
—
—
—
—
7.72 x 10~®
8.41 x 10
7.72 x 10";?
7.84 x 10~b
6.6 x 10~5
6.6 x 10
1.2 x 10~5
3.0 x 10 ;
5.9 x 10":
4.3 x 10"5
:g
<2%
<2%
<2%
<2%
<2%
99%
99%
99%
96%
64%
44%
66%
82%
52%
58%
30
-------
In each boring under the landfill a series of samples were taken at
increasing depth. Again, no consistent pattern could be observed relating
the physical characteristics to the depth (or elevation).
None of the physical tests with the possible exception of permeability
measurements at site B showed any consistent differences between samples taken
directly under the landfill and those taken outside the landfill. No consis-
tent pattern could be found in samples taken at differing depths in the same
borings under the landfills. Any differences which do occur apparently are
confined to a narrow range immediately at the interface between the refuse and
the soil. Detection of these would probably require examination of a core
through this interface region in very fine detail. None of the usual
engineering tests demonstrated any effects which could be attributed to
attenuation.
CHEMICAL ANALYSES OF GROUNDWATER
The goal of the groundwater investigation is to determine if changes
in chemical parameters observed in different borings at each site could be
related to the position of the boring with regard to the landfill and the
direction of groundwater movement. A survey of the literature suggests that
of the chemical parameters measured those most likely to indicate contamination
from leachate in the groundwater are sulfate, chloride, total organic carbon,
calcium, iron, magnesium, manganese and sodium (2,3). The minor and trace
elements appearing in the groundwater around a landfill vary widely depending
on the concentrations present in the waste at a particular landfill.
The tabulation of groundwater analyses obtained from wells at sites A,
B and C are presented in Tables 11-13. The data are divided into three
groups for each site; those up the groundwater gradient from the landfill,
those under the landfill and those down the groundwater gradient from the
landfill. The three groups of samples at each site show different means for
the parameters measured and initial statistical analysis indicated widely
different variances. Because of these inhomogeneous variances, the re-
stricted number of samples in each group, and the large number of determina-
tions that fall below the limits of detection, a non-parametric (distribution-
free) analysis of variance techniques was used to determine if differences
between means of parameters measured were significant. The statistical
technique employed was the Kruskal-Wallis one-way analysis of variance (12,13).
This test requires only that data have an underlaying continuous distribution
and that the data can be ranked. This test does not require that the data
have a normal distribution or be homogeneous with regard to variance. Because
of the differences in numbers of samples at different sites, two different
levels of significance (95.4% and 96.8%) were used.
The analysis of variance results are given in Table 14. Strong influence
of the type of geologic material at each site is evident in the differences
in background levels of metals present. Site A was underlain by clean glacial
outwash consisting primarily of quartz sand. The upgradient groundwater
31
-------
TABLE 11. CHEMICAL COMPOSITION OF GROUNDWATER OBTAINED FROM BORINGS AT LANDFILL A
Parameters
so4
so3
Cl
N03-N
N02-N
CN
TOC
Ca
Fe
Kg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
Up groundwater gradient
Boring Boring Boring
458
<8
<1
<5
<0.01
<0.01
<0.01
<1
<0.03
<0.05
<0.03
<0.03
<0.03
0.005
<0.02
<0.02
<0.03
<0.03
<0.02
< 0.0002
<0.03
<0.1
<0.002
<0.03
<8
<1
<5
<0.01
<0.01
<0.01
<1
<0.03
<0.05
<0.03
<0.03
<0.03
0.003
<0.02
<0.02
<0.03
<0.03
<0.02
<0*.0002
<0.03
<0.1
<0.002
<0.03
<8
<1
<5
<0.01
<0.01
<0.05
<1
<0.03
<0.05
<0.03
<0.03
<0.03
0.006
<0.02
<0.02
<0.003
<0.03
<0.02
<0.0002
<0.03
<0.1
<0.002
<0.03
Under landfill
Boring Boring Boring
132
25
<1
5
0.38
0.09
<0.01
21
34.3
3.5
17.10
3.2
19.80
0.002
0.02
<0.02
<0.03
<0.03
<0.02
<0.0002
0.04
<0.1
<0.002
0.35
47
<1
5
0.02
0.03
0.01
48
69.0
10.5
48.50
3.0
72.10
0.003
0.02
<0.02
<0.03
<0.03
<0.02
<0.0002
0.07
<0.1
<0.002
0.24
23
<1
5
<0.01
0.04
<0.01
50
127.0
18.6
39.50
4.9
63.20
0.007
0.02
<0.02
<0.03
<0.03
<0.02
<0.0002
0.13
<0.1
<0.002
1.36
Down groundwater
gradient
Boring Boring
6 7
26
<1
5
<0.01
0.04
<0.01
20
35.0
22.0
35.00
8.3
41.00
0.006
0.02
<0.02
<0.03
<0.03
<0.02
<0.0002
0.12
<0.1
<0.002
0.29
35
<1
5
<0.01
0.03
<0.01
27
35.5
22.0
35.50
10.3
7.80
0.003
0.02
<0.02
<0.03
<0.02
<0.0002
0.21
<0.1
<0.002
0.44
Note: All values are in mg/i.
-------
TABLE 12. CHEMICAL COMPOSITION OF GROUNDWATER OBTAINED FROM BORINGS AT LANDFILL B
Parameters
so4
so3
Cl
N03-N
N02-N
CN
TOC
Ca
Fe
Mg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
Up groundwater gradient
Boring Boring Boring
456
<8
-------
TABLE 13. CHEMICAL COMPOSITION OF GROUNDWATER OBTAINED FROM BORINGS AT LANDFILL C
Parameters
S°4
so3
Cl
N03-N
N02-N
CN
TOC
Ca
Fe
Mg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
Up groundwater gradient
Boring Boring Boring
678
<8
20
0.03
<0.01
<0.01
5
8.0
0.10
7.50
0.20
12.00
0.002
0.04
<0.02
0.03
<0.03
<0.02
0.0081
0.08
0.173
<0.002
0.03
<8
5
0.02
<0.01
<0.01
1
2.6
0.07
1.50
0.15
5.90
0.002
<0.02
<0.02
0.70
<0.03
<0.02
0.0039
0.05
0.114
<0.002
0.69
<8
15
0.68
<0.01
<0.01
4
1.6
0.12
2.30
0.50
6.00
0.002
<0.02
<0.02
0.12
<0.03
<0.02
0.0013
0.08
0.111
<0.002
0.12
Boring
9
<8
5
0.11
<0.01
<0.01
2
7.9
0.13
1.20
0.06
2.90
0.002
0.06
<0.02
0.04
<0.03
<0.02
0.0018
0.38
0.133
<0.002
0.07
Under landfill
Boring Boring Boring
123
9
1
5
0.04
<0.01
0.01
95
37.0
4.90
16.00
7.12
7.50
0.002
0.12
<0.02
<0.03
<0.03
<0.02
0.0012
1.61
0.274
<0.002
2.73
24
415
0.03
<0.01
0.01
208
34.0
18.20
56.00
12.30
220.00
0.003
1.45
<0.02
<0.03
<0.03
<0.02
0.0014
0.42
0.368
<0.002
0.64
8
2
15
0.02
<0.01
<0.01
16
10.0
0.08
4.4
0.19
6.70
0.002
1.06
<0.02
<0.03
<0.03
<0.02
0.0018
0.07
0.140
<0.002
0.06
Down groundwater
gradient
Boring Boring
4 5
8
365
<0.01
<0.01
<0.01
30
72.0
2.77
68.00
31.90
71.00
0.002
1.04
<0.02
0.05
<0.03
<0.02
0.0012
0.06
0.493
<0.002
0.20
8
1
25
0.01
<0.01
<0.01
8
7.0
0.09
7.50
5.19
5.90
0.002
<0.02
<0.02
0.09
<0.03
<0.02
0.0012
0.08
0.163
<0.002
0.09
Note: All values are in mg/fc
-------
TABLE 14. RESULTS OF ANALYSIS OF VARIANCE FOR GROUNDWATER CHEMISTRY
Parameter
SO,
4
SO,
3
Cl
N03-N
N02-N
CN
TOC
Ca
Fe
Mg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
Site A*
S
N
S
NS
NS
NS
S
S
S
S
S
S
NS
S
NS
N
NS
N
N
S
N
N
NS
Site B*
S
NS
NS
S
N
N
NS
NS
NS
NS
NS
NS
NS
NS
NS
N
NS
N
NS
NS
N
NS
NS
Site C**
S
NS
NS
S
N
S
S
NS
NS
NS
NS
NS
NS
NS
N
NS
N
N
NS
NS
NS
N
NS
S = Significant difference in means.
NS = No significant difference in means.
N = No present in measurable quantities in any sample.
* = Tested at 96.8% confidence level.
** = Tested at 95.4% confidence level.
35
-------
samples (Wells A-4, A-5, A-8) contain very low levels of many elements. There-
fore the contrast with the sub-landfill samples is strong and the number of
statistically significant differences in averages is large. Site B and site
C show higher background levels in the upgradient wells reflecting the more
complex chemical composition of the materials in the area (clays at site B;
weathered metamorphic rocks at site C). Therefore, the contrast between the
upgradient groundwater samples and the sub-landfill samples is correspondingly
weaker and the number of statistically significant differences in mean values
for chemical parameters is lower.
The most consistent effect of leachate contamination observed in the
groundwater is the increased sulfate noted in wells under the landfill as
contrasted with upgradient wells. This increase was observed at all three
landfills that were investigated. Increases in nitrate, or total organic
carbon were observed in the sub-landfill groundwater samples in two out of the
three sites. At site A, probably because of this site's low background levels,
significant contrasts could also be found in chloride, calcium, iron, magnesium,
sodium, boron, and nickel. Site C showed a significant contrast in cyanide
levels under and upgradient from the landfill.
The results of this investigation agree with previous investigations in
indicating that increased levels of sulfate, nitrate and organic carbon levels
are related to pollution from landfill leachate (3,4,14). Cyanide measurements
are not usually made on groundwater in municipal landfill areas, but as indicated
by site C, cyanide may be a worthwhile measurement to make on leachate-contaminated
water.
CHEMICAL ANALYSES OF DISTILLED WATER EXTRACTS
The goal of distilled water extraction was to determine the availability
of the potential pollutants in the soil samples to water in contact with the
soil. The availability of particular materials in sub-landfill soil to a
distilled water extract may vary greatly from site to site. The content of
this soil extract depends upon the:
a) original constituents in the soil and their solubilities,
b) way in which the original constituents have reacted with the weak
organic acids in leachate and the solubilities of new products
produced,
c) extent to which the water-soluble and leachate-soluble materials
have been removed from the soil through solution,
d) solubilities of materials that are precipitated, filtered, or
adsorbed from the leachate passing through the soil,
e) pH and redox conditions in the soil, especially as this effects the
solubility of iron and manganese, the survival of nitrates and
sulfates, and the production of sulfide, and
36
-------
f) amount and character of the interstitial water present in the sample.
Comparison of Distilled Water Extracts from Beneath and Outside the Landfills
The tabulation of analyses of distilled water extracts of soil samples
is given in Tables 15-20. Many of the analyses are close to or below the limits
of detection indicating that in general very little material is available to
contacting water in soils either under or away from the landfills. A statistical
comparison was made between analyses of extracts obtained from samples immediate-
ly under the landfill and those collected at comparable depths below the surface
(but above the water table) outside the landfill. A randomization procedure
was used to test the significance of differences between means of the two sample
sets. Using five samples, an 80% significance level can be obtained in a two-
tailed test. The results of the randomization test are given in Table 21.
Only sulfate levels show a significant difference between means of
samples obtained inside and outside the landfill at all three sites. There is,
however, no consistent relationship in the behavior of sulfate between sites.
At sites A and B the sulfate levels are slightly higher in the water leach
from soil under the landfill. At site C the reverse is true. At all three
sites, sulfate is moving from the landfill through the sub-refuse soil as
shown by the increased sulfate levels in groundwater. At site C, sulfate
from the leachate may be moving through the soil without being stopped or
sulfate trapped in the soil may be reduced to sulfide through the activity of
anaerobic bacteria decomposing organic materials in the leachate.
Chloride levels in soil extracts were significantly different inside and
outside the landfills at sites B and C. At site C the sub-landfill soil
extract was high in chloride compared to the samples outside the fill. At
site B the reverse was true. Groundwater analyses indicated that chloride
levels increased significantly only under landfill site C. The increased
chloride in the soil sample at site C is to be expected from the increased
supply of chloride from leachate. Chloride ion is not readily adsorbed to
solid materials and does not readily precipitate. The increased chloride
observed in the water extract from soil below the landfill at site C is pro-
bably due to chloride in solution in the water associated with the wet
sample. At site B the decrease in chloride in extract from soil under the
landfill is consistent with the low chloride levels seen in the groundwater.
Nitrate levels were significantly different inside and outside of the
landfill only at site C. Very low nitrate levels were observed inside the
landfill and higher levels outside. The nitrogen present in soil under the
landfill might be converted from nitrate to ammonium ion through bacterial
activity associated with the leachate; reducing nitrate below levels observed
in similar surrounding soils. Published analyses indicate much of the
nitrogen in leachate is present as ammonium ion (1), not as nitrate, indicating
nitrate reduction can occur, and that nitrogen added to the sub-landfill soil
probably is in the form of ammonium ion.
Cyanide levels varied significantly only at site B. The analyses are
mostly at or very near the limits of detection for this constituent and so
37
-------
TABLE 15. ANALYSES OF DISTILLED WATER EXTRACTS OF SOIL SAMPLES FROM EXPERIMENTAL BORINGS AT SITE A
Boring
and sample
Elevation (m)
2C4
243.00
2C5
237.11
2C6
232.08
3C1
250.53
3C2
249.53
3C3
247.60
3C4
240.27
3C5
235.72
3C6
230.73
Depth below
raw/soil
interface (m) 7.99 13.87 18.90 0.00 1.01 2.93 10.26 14.81 19.80
Ht. above water
table (m) 11.99 6.10 1.07 19.31 18.31 16.38 9.05 4.50 -0.49
Co
oo
Cone, (mg/8.)
SO,
Cfc3
NO,-N
N02-N
CN
TOC
Ca
Fe
Mg
Mn
Ma
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
9
<5
0.01
<0.01
<0.01
6
0.18
ND
0.10
<0.03
0.42
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.21
8
<5
<0.01
<0.01
<0.01
6
0.15
ND
0.12
<0.03
0.94
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
1.39
9
<5
0.02
<0.01
<0.01
7
2.24
ND
0.80
<0.03
0.70
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.38
9
<5
<0.01
<0.01
<0.01
7
0.54
ND
0.22
<0.03
2.29
0.006
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.07
<0.10
<0.002
0.35
9
<5
<0.01
<0.01
<0.01
4
0.77
ND
0.14
<0.03
6.47
0.010
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.04
<0.10
<0.002
0.22
9
<5
<0.01
<0.01
<0.01
5
0.55
ND
0.23
<0.03
3.58
0.004
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
1.12
9
<5
<0.01
<0.01
<0.01
2
2.23
ND
1.31
<0.03
0.19
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.06
9
<5
<0.01
<0.01
<0.01
7
1.53
ND
0.92
<0.03
2.97
0.004
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.21
9
<5
<0.01
<0.01
<0.01
5
0.44
ND
0.13
<0.03
1.90
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
1.14
ND - Not determined
-------
TABLE 15. (continued)
Boring
and sample
1C1
1C2
1C3
1C4
1C5
1C6
1C7
2C1
2C2
2C3
Elevation (m)
Depth below
raw/soil
interface (m)
Ht. above water
table (m)
250.57 249.77 247.58 242.08 234.81 230.83 230.83 250.98 250.14 247.99
0.00
18.06
0.82
17.24
3.02
15.05
8.52 15.78
19.77
19.77
9.55
2.28
-1.70 -1.70
0.00
19.97
0.84
19.13
2.99
16.98
Cone, (mg/fc)
S°4
Cl3
NO--N
3
"of*
TOC
Ca
Fe
Mg
Mn
Na
Aa
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
9
<5
0.
<0.
<0.
9
0.
30
01
01
31
ND
0.
<0.
2.
0.
<0.
<0.
<0.
<0.
0.
48
03
94
006
02
02
03
03
03
ND
0.
<0.
<0.
0.
09
10
002
78
10
<5
0.01
<0.01
<0.01
11
1.40
ND
0.97
<0.03
1.40
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
1.10
9
<5
<0.01
<0.01
<0.01
8
0.35
ND
0.33
<0.03
1.10
0.001
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.11
10
5
0.03
<0.01
<0.01
8
0.70
ND
0.67
<0.03
2.62
0.002
<0.02
<0.02
<0.03
0.03
<0.02
ND
0.08
<0.10
<0.002
0.38
9
5
<0.01
<0.01
<0.01
6
0.59
ND
0.18
<0.03
0.93
0.001
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.13
42
5
0.13
0.06
<0.01
8
3.03
ND
1.69
<0.03
0.53
0.008
<0.02
<0.02
<0.03
0.05
0.04
ND
0.05
<0.10
<0.002
0.82
9
<5
<0.01
<0.01
<0.01
5
1.22
ND
0.29
<0.03
1.78
0.001
<0.02
0.02
0.03
<0.03
<0.02
ND
0.07
<0.10
<0.002
0.29
9
<5
0.38
0.09
<0.01
10
0.41
ND
0.30
0.07
3.20
0.002
<0.02
<0.02
<0.03
0.28
0.17
ND
2.62
<0.10
<0.002
4.65
9
<5
0.06
<0.01
<0.01
9
3.58
ND
0.68
0.06
1.82
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.10
9
<5
<0.01
<0.01
<0.01
10
0.95
ND
0.20
<0.03
1.94
0.001
<0.02
<0.02
<0.03
0.03
0.02
ND
<0.03
<0.10
<0.002
0.46
(continued)
-------
TABLE 16. ANALYSES OF DISTILLED WATER EXTRACTS OF SOIL SAMPLES FROM CONTROL BORINGS AT SITE A
Boring
and sample
Elevation (m)
Ht. above water
table (m)
Cone. (mg/X,)
SO
SO*
NO.-N
NOjj-N
CN
TOC
Ca
Fe
Mg
~*o
Mn
Na
As
B
Be
Cd
Cr
Cu
HE
••*&
Ni
Pb
Se
Zn
6C1
251.09
19.99
9
<3_
<5
0.02
<0.01
<0.01
3
0.37
ND
0.16
<0.03
0.27
0.004
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.91
6C2
250.20
19.10
10
<1
<5
0.01
<0.01
<0.01
<1
0.30
ND
0.23
<0.03
0.21
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.14
6C3
248.08
16.98
8
<1
<5
0.01
<0.01
<0.01
3
1.26
ND
0.51
<0.03
0.30
0.001
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.25
6C4
242.05
10.95
8
<1
<5
0.16
<0.01
<0.01
2
0.46
ND
0.28
<0.03
0.32
0.001
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
<0.03
6C5
236.86
5.76
8
<1
<5
0.06
<0.01
<0.01
2
0.30
ND
0.21
0.04
0.39
0.001
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.68
6C6
230.84
-0.26
8
^1
<5
<0.01
<0.01
<0.01
<:L
0.18
ND
0.16
<0.03
0.49
0.001
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.27
7C1
250.49
14.97
8
<1
<5
0.05
<0.01
<0.01
<:L
0.51
ND
0.14
<0.03
0.73
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.35
7C2
250.15
14.63
8
^1
<5
0.04
<0.01
<0.01
<:L
0.72
ND
0.35
<0.03
0.39
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.09
7C3
247.99
12.47
8
^1
<5
0.27
<0.01
<0.01
<:L
0.98
ND
0.33
0.03
0.70
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.22
7C4
242.23
6.71
9
<1
<5
0.02
<0.01
<0.01
5
0.87
ND
0.35
0.06
0.61
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
<0.03
7C5
236.37
-0.85
10
^1
<5
0.05
-0.01
<0.01
5
1.24
ND
0.54
0.03
0.37
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.20
7C6
233.32
-2.20
10
** J-
<5
0.20
<0.01
<0.01
3
2.02
ND
0.91
0.04
0.33
0.002
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
<0.002
0.39
ND - Not determined
NOTE: All borings are positioned downdip on the groundwater gradient.
-------
TABLE 17. ANALYSES OF DISTILLED WATER EXTRACTS OF SOIL SAMPLES FROM EXPERIMENTAL BORINGS AT SITE B
Boring
and sample
Elevation (m)
1C1
55.93
1C 2
54.06
2C1
56.77
2C2
55.85
2C3
53.72
3C1
56.74
3C2
55.74
3C3
53.50
Depth below soil/raw
interface (m) 0.00 1.87 0.00 0.92 3.05 0.00 1.00 3.24
Ht. above water
table (m) 1.57 -0.30 5.83 4.91 2.78 3.51 2.51 0.27
Cone, (mg/il)
SO
SO,
Cl3
NO.-N
NO,-N
CN2
TOC
Ca
Fe
Mg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
<8
<^
5
0.04
<£*.01
0.01
14
20.00
0.50
11.70
0.30
21.00
ND
0.05
<0.02
<0.03
0.05
<0.02
ND
0.10
<0.10
ND
<0.03
25
<1
8
0.07
<0.01
0.01
10
13.00
0.48
5.60
0.99
6.70
ND
0.06
<0.02
<0.03
0.05
<0.02
ND
0.08
<0.10
ND
<0.05
<8
<1
<5
0.02
<0.01
0.01
16
21.00
0.25
8.50
0.04
30.00
ND
0.15
<0.02
<0.03
0.07
<0.02
ND
0.13
<0.10
ND
<0.10
<8
<^
<5
0.05
<0.01
0.01
14
18.00
0.20
8.00
0.11
13.00
ND
0.09
<0.02
<0.03
0.05
<0.02
ND
0.11
<0.10
ND
<0.10
<8
<^
8
0.05
<0.01
<0.01
6
19.00
0.05
6.60
<0.03
3.00
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.05
<0.10
ND
<0.10
9
<^
<5
0.27
<0.01
0.02
27
6.50
0.40
4.10
<0.03
66.00
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.06
<0.10
ND
<0.10
<8
<^
<5
0.17
<0.01
0.01
12
15.00
0.10
12.00
0.26
9.40
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.05
<0.10
ND
<0.10
13
<^
<5
<0.01
<0.01
<0.01
4
21.00
0.11
9.90
<0.03
4.10
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.07
<0.10
ND
<0.10
ND = Not determined.
-------
TABLE 18. ANALYSES OF DISTILLED WATER EXTRACTS OF SOIL SAMPLES FROM CONTROL BORINGS AT SITE B
Boring
and sample
5C1
5C2
5C3
6C1
6C2
6C3
7C3
Elevation (m) 55.28 54.38 52.44 54.26 53.35 51.22 42.00
Ht. above water
table (m) 1.93 1.03 -0.91 4.11 3.20 1.07 0.10
Position in
groundwater
gradient
Cone. (mg/Jl)
SO.
A
so.
Cl3
NO,-N
NOI-N
CN
TOC
Ca
Fe
Mg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
updip
<8
<]_
8
1.56
<0.01
0.01
3
36.00
0.14
10.50
<0.03
3.30
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.12
<0.10
ND
<0.03
updip
<8
-------
TABLE 19. ANALYSES OF DISTILLED WATER EXTRACTS OF SOIL SAMPLES FROM EXPERIMENTAL BORINGS AT SITE C
Boring
and sample
Elevation (m)
Depth below
mw/soil
interface (m)
Ht. above water
table (m)
Cone. (mg/JO
S°4
SO,
ci3
NO -N
NO^-N
CN
TOC
Ca
Fe
Mfe
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
1C1
131.41
0.00
4.40
9'
<]_
5
0.03
<0.01
<0.01
21
0.60
0.09
1.60
0.60
2.20
ND
<0.02
<0.02
0.04
<0.03
<0.02
ND
0.06
ND
ND
0.06
1C2
130.48
0.93
3.47
<8
<2_
5
0.03
<0.01
<0.01
18
2.10
0.15
1.30
0.27
2.00
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
ND
ND
0.20
1C3
128.34
3.07
1.33
<8
-------
TABLE 20. ANALYSES OF DISTILLED WATER EXTRACTS OF SOIL SAMPLES FROM CONTROL BORINGS AT SITE C
Boring
and sample
Elevation (m)
Ht . above
water
table (m)
Position in
groundwater
gradient
Cone, (mg/2)
SO.
SO*
Cl3
NO.-N
NO,-N
cS
TOC
Ca
Fe
Mg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
6C1
132.46
5.42
Updip
12
<1
5
1.34
<0.01
<0.01
14
6.90
0.89
1.50
1.76
2.60
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.04
<0.10
ND
0.13
6C2
131.54
4.50
Updip
<8
<1
5
1.69
<0.01
<0.01
13
1.10
0.34
1.20
<0.03
4.60
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
ND
0.07
6C3
129.41
2.37
Updip
11
<1
10
1.75
<0.01
<0.01
14
1.40
5.26
1.50
<0.03
8.10
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
ND
0.07
6C4
127.88
0.84
Updip
<8
<1
5
3.06
<0.01
<0.01
6
2.10
0.10
1.00
<0.03
6.60
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
ND
0.08
6C5
126.06
-0.98
Updip
<8
<1
20
1.54
<0.01
<0.01
2
2.60
0.10
1.00
<0.03
3.20
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.03
<0.10
ND
0.27
7C4
121.80
0.09
Updip
<8
<1
20
0.87
<0.01
<0.01
1
2.20
0.05
1.80
<0.03
3.60
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
ND
0.11
8C3
130.14
-0.36
Updip
<8
<1
30
1.91
<0.01
<0.01
5
2.70
0.08
3.90
0.14
2.30
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
0.05
1.40
ND
0.18
9C1
143.47
11.47
Updip
20
2
5
1.91
<0.01
<0.01
6
10.00
7.95
2.20
0.03
2.80
ND
0.10
<0.02
<0.03
<0.03
<0.02
ND
0.05
0.10
ND
0.07
9C2
142.57
10.57
Updip
10
<1
15
1.82
<0.01
<0.01
6
23.00
0.08
2.50
<0.03
2.20
ND
0.04
<0.02
<0.03
<0.03
<0.02
ND
0.10
0.20
ND
0.34
9C3
140.44
8.44
Updip
16
2
5
1.57
<0.01
<0.01
1
7.40
0.06
2.90
0.05
2.10
ND
0.04
<0.02
<0.03
<0.03
<0.02
ND
0.05
0.10
ND
0.23
9C4
136.17
4.17
Updip
16
<1
5
0.07
<0.01
<0.01
6
2.30
0.05
0.50
<0.03
1.90
ND
0.04
<0.02
<0.03
<0.03
<0.02
ND
<0.03
<0.10
ND
0.15
9C5
131.91
-0.09
Updip
<8
<1
15
1.98
<0.01
<0.01
6
2.70
<0.05
1.00
<0.03
2.10
ND
<0.02
<0.02
<0.03
<0.03
<0.02
ND
<0.03
1.59
ND
0.08
4C6
124.74
-0.66
Downdip
<8
<1
75
<0.01
<0.01
<0.01
4
14.00
0.12
8.00
3.31
6.70
ND
0.02
<0.02
<0.03
<0.03
<0.02
ND
0.10
<0.10
ND
0.13
5C4
126.92
-0.12
Downdip
<8
<1
30
1.27
<0.01
<0.01
6
3.80
0.09
1.80
0.26
2.10
ND
0.02
<0.02
<0.03
<0.03
<0.02
ND
0.03
<0.10
ND
0.15
ND = Not determined.
-------
TABLE 21. RESULTS OF RANDOMIZATION TEST ON DISTILLED WATER EXTRACTS OF SOIL
SAMPLES DIRECTLY UNDER THE LANDFILLS AND AT COMPARABLE DEPTHS
OUTSIDE THE LANDFILLS
Parameters
SO.
4
SO,
3
Cl
NO,-N
3
NO--N
2
CN
TOG
C*
*i!
Mg
Mn
Na
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
Site A
S
N
N
NS
N
N
S
NS
ND
S
N
S
NS
N
N
N
S
S
ND
S
N
N
NS
Site B
S
N
S
NS
N
S
S
S
S
NS
S
S
ND
S
N
N
S
N
ND
NS
N
ND
N
Site C
S
N
S
S
N
N
NS
S
S
NS
NS
NS
ND
NS
N
N
N
N
ND
NS
ND
ND
S
N = Too few samples above detection limit.
ND = Not determined.
NS - Not significant at 80% level.
S - Significant at 80% level.
45
-------
cannot be regarded as firm evidence of increased cyanide levels under the
landfill at site B.
Total organic carbon (TOC) analyses show a pronounced difference between
sub-landfill and control samples at both sites A and B. Samples below the
landfills were consistently higher in TOC than those outside the landfill.
All of the analyses under the landfills were well above the detection limits
and at least double the analyses of control samples from outside the landfill.
The groundwater analyses also indicated higher TOC levels in some borings
beneath each landfill. These increased organic carbon levels can be attri-
buted to material derived from the refuse.
Calcium levels in extracts from soils below the landfills at sites B
and C are significantly lower than those extracts obtained from similar samples
outside the landfills. However, calcium levels in the groundwater showed an
increase under each landfill. These analyses indicate that the calcium
availability is significantly decreased at sites B and C due to removal of
soluble calcium compounds by landfill leachate or the production of insoluble
calcium compounds by reaction with leachate.
Total iron levels were significantly different in soil extracts obtained
below and outside the landfills at sites B and C. At site B the soil under
the landfill showed more water-extractable iron than the soil samples outside
the landfill. Site C showed the reverse trend. The availability of iron to
contacting water is related to the redox conditions present, the complexing
properties of organic materials in the soil, and the presence of anions such
as sulfide, etc. that can produce insoluble iron compounds. The lack of
extractable iron under the landfill at site C is consistent with the evidence
of sulfate reduction discussed above.
Magnesium in water extracts showed a significant difference only at site
A. Magnesium availability was only slightly higher in soil under the landfill
than in soil outside the landfill.
Manganese levels were very slightly higher in soil extracts obtained
under the landfill at site B as compared to samples outside the landfill.
However, the observed levels are close to the analytical limits of detection.
Sodium in the water extracts showed a significant difference between
control and experimental samples at sites A and B. At both sites, the avail-
able sodium increased under the landfill as compared to samples outside the
landfill area. Sodium is a common constitutent in municipal landfill
leachate; it does not really precipitate and is only weakly adsorbed.
Boron and the trace metals chromium, copper and nickel show higher
levels in water extracts from soils under the landfills as compared to soils
outside the landfill. These elements may be either freed from the soil by
organic acids from the leachate or introduced in a soluble form in the leachate.
Zinc levels obtained from water extracts of soil samples at site C showed
significant differences between samples collected under the landfill and those
collected outside the landfill. The extracts from outside the landfill were
46
-------
slightly higher suggesting zinc was less available in the area affected by
landfill leachate. Zinc is the only trace metal that could be shown to be
extracted in greater concentrations outside the landfill than below the land-
fill. The immobilization of zinc may be related to sulfide production at site C.
The major factors that control availability of contaminants to a distilled
water extract in sub-landfill soils studied are the supply of materials moving
from the refuse to the soil, and the decrease in soluble constituents that
occurs in the soil either due to leaching or production of insoluble compounds
by reaction with leachate. Sulfate, if it is not reduced to sulfide, is more
available under the landfill due to influx from the refuse. Chloride, total
organic carbon, sodium and magnesium and all of the trace metals with the
exception of zinc can appear in greater quantities in water extracts probably
due to greater supply of these materials in a soluble form in the incoming
leachate. Calcium in two cases showed a decrease of availability in sub-refuse
soil possibly due to prior removal by solution or the formation of insoluble
calcium compounds (possibly calcium salts of fatty acids). Iron and zinc at
one site (site C) showed decreased availability in water extracts that can
probably be attributed to formation of sulfides of these metals.
Vertical Variation of Constituents
in the Distilled Water Extracts of Soil Samples
For those elements at each site that did show a significant difference in
means between control (outside landfill) samples and experimental (inside land-
fill) samples, a test was made for a significant relationship between the availa-
ble concentration of a particular constituent and sample elevation (or sample
depth). The model suggests that those materials derived from the refuse would
show a positive correlation with elevation in the experimental borings (below
the landfill). Soil constituents that are being dissolved by the landfill
leachate and moved down out of the soil and into the groundwater should, in
the model situation, show a significant negative correlation with sample
elevation. Outside the landfill the distribution of available soil constituents
depends on weathering processes and the concentration and solubility of the
particular material and could therefore have a significant positive or negative
correlation with elevation, or no significant correlation at all.
The Spearman rank correlation was used to judge the strength of association
because this technique could be used with small sample numbers where the
statistical distribution is not known. In several cases, the small number of
samples having detectable quantities of a particular constituent made it im-
possible to judge the significance of the correlation coefficients obtained.
The results of the statistical tests are given in Tables 22-24. Plots of
concentration versus sample elevation for all constituents that showed
statistically significant relations with elevation in experimental borings are
presented in Figures 7-18. Plots of significant relationships in control holes
are included for contrast. The only significant correlation with sample
elevation in borings through the landfill at site A (Borings 1, 2, and 3) in-
volves total organic carbon. The correlation is positive as would be expected
for a constituent derived from the refuse in the landfill. No significant
correlation between sample elevation and total organic carbon could be observed
in the control holes.
47
-------
TABLE 22. CORRELATION OF CHEMICAL ANALYSES OF DISTILLED WATER EXTRACTS
OF SOIL SAMPLES WITH SAMPLE ELEVATION AT SITE A
Boring
No.
S°4
TOC
Mg
Na
Cr
Cu
Ni
1
NS
SP
NS
NS
*
*
NS
Experimental
2
NS
NS
NS
NS
*
*
*
3
NS
NS
NS
NS
*
*
NS
Control
6 7
SP SN
NS NS
NS SN
SN SP
*
* *
SP = Significant positive correlation at 95% level.
SN = Significant negative correlation at 95% level.
NS = Not significant.
* = Too few samples above detection limit.
-------
TABLE 23. CORRELATION OF CHEMICAL ANALYSES OF DISTILLED WATER EXTRACTS
OF SOIL SAMPLES WITH SAMPLE ELEVATION AT SITE B
Boring Experimental
No.
SO.
4
Cl
CN
TOC
Ca
Fe
Mn
Na
B
Cr
Zn
1 2
— ** *
— *
*
SP
NS
SP
NS
SP
SP
SP
SP
3 5
NS *
* NS
SP *
SP NS
SN SP
NS NS
* *
SP SN
* *
* *
* *
Control
6
*
SN
*
SN
SN
NS
*
NS
*
*
*
SP =
SN =
NS =
* =
** =
Significant positive correlation at 95%
Significant negative correlation at 95%
Not significant correlation.
Too few samples above detection limits.
Too few samples for significant test for
level.
level.
this boring.
-------
TABLE 24. CORRELATION OF CHEMICAL ANALYSES OF DISTILLED WATER EXTRACTS
OF SOIL SAMPLES WITH SAMPLE ELEVATION AT SITE C.
- - -
Boring
No.
S°4
Cl
N03
Ca
Fe
Zn
1
*
NS
NS
SN
NS
SN
Experimental
2
*
NS
NS
SP
NS
NS
Control
3
*
NS
NS
NS
*
NS
6
SP
NS
NS
NS
NS
NS
9
NS
NS
NS
NS
sp
NS
^~-
SP = Significant positive correlation at 95% level.
SN = Significant negative correlation at 95% level.
NS = Not significant.
* = Too few samples above detection limit.
50
-------
255
TOC CONCENTRATION, mg/t
2 4 6 8 10
12
i i i i r
i i
250
LEGEND
D IA
245
Z
o
1
UJ
_l
UJ
240
235
o
Q
230 L
Figure 7. Variation of total organic carbon (TOC) concentration in
distilled water extracts of soil/sediment samples with
elevation in boring 1 at site A. Inverted triangle symbol
indicates water table.
-------
0.0
255
Na CONCENTRATION, mg/t
1.0 2.0 3.0 4.0
5.0
250
.245
z"
o
1
3240
UJ
235
230 L
LEGEND
o 2A
• 6A
• 7A
Figure 8. Variation of sodium concentration in distilled water
extracts of soil/sediment samples with elevation in borings
2, 6, and 7 at site A. Inverted triangle symbols indicates
water table in each boring.
52
-------
0.000
58
CN CONCENTRATION, mg/i
0.005 0.010 0.015 0.020
0.025
57
56
,55
z
g
h-
UJ
i54
53
52
LIMIT OF DETECTION
LEGEND
a 3B
Figure 9. Variation of cyanide concentration in distilled water extracts of
soil/sediment samples with elevation in boring 3 at site B.
53
-------
58
57
56
.55
Z
UJ
_l
UJ
54
53
52
51 L
TOC CONCENTRATION,
10 20 30
40
50
LEGEND
o 2B
A 3B
• 6B
Figure 10. Variation in total organic carbon (TOC) concentration in distilled
water extracts of soil/sediment samples with elevation in borings
2, 3, and 6 at site B.
54
-------
58
57
56
.55
z
o
1
UJ
53
52
Ca CONCENTRATION, mg/£
10 20 30 40
50
LEGEND
a 3B
o 5B
• 6B
Figure 11. Variation of calcium concentration in distilled water extracts of
soil/sediment samples with elevation in borings 3, 5, and 6 at
site B.
55
-------
0.00
58
57
56
55
Z
g
I
UJ
53
52
51
Figure 12.
Fe CONCENTRATION, mg/1
0.05 0.10 0.15 0.20
0.25
LEGEND
o 2B
Variation of iron concentration in distilled water extracts of
soil/sediment samples with elevation in boring 2 at site B.
56
-------
58
Na CONCENTRATION, mg/I
20 40 60 80
100
57
56
.55
Z
O
I
UJ
53
52
LEGEND
o 2B
A 3B
a 5B
5IL
Figure 13.
Variation of sodium concentration in distilled water extracts of
soil/sediment samples with elevation in borings 2, 3, and 5 at
site B.
57
-------
0.00
58
57
56 -
Z
o
I
Ul
53
52
51 L
Figure 14.
B CONCENTRATION, mg/i
0.05 0.10 0.15 0.20
0.25
LIMIT OF DETECTION
LEGEND
o 2B
Variation of boron concentration in distilled water extracts of
soil/sediment samples with elevation in boring 2 at site B.
58
-------
0.00
58
57
56
.55
z
g
\
LU
ul54
53
52
51
Figure 15.
Cr CONCENTRATION, mg/i
0.02 0.04 0.06 0.08
0.10
LIMIT OF DETECTION
LEGEND
o 2B
Variation of chromium concentration in distilled water extracts
of soil/sediment samples with elevation in boring 2 at site B.
59
-------
57
56
,55
Z
o
\
UJ
53
52
5IL
Figure 16.
Zn CONCENTRATION,
0.02 0.04 0.06
0.08
0.10
LIMIT OF DETECTION
LEGEND
o 2B
Variation of zinc concentration in distilled water extracts of
soil/sediment samples with elevation in boring 2 at site B.
60
-------
145
Ca CONCENTRATION, mg/Jt
5 10 15 20
140
J35
z
o
I
UJ
-I 130
ui
125
120 L
25
—I
LEGEND
a 1C
o 2C
A 9C
Figure 17. Variation of calcium concentration in distilled water extracts
of soil/sediment samples with elevation in borings 1, 2, and 9
at site C. Inverted triangle symbols indicate water table in
each boring.
61
-------
000
145
Zn CONCENTRATION, mg/Jt
0.05 0.10 0.15 0.20 0.25 0.30
140
135
z
o
u
_l
UJ
130
125
120 L
LEGEND
o 1C
Figure 18. Variation of zinc concentration in distilled water extracts of
soil/sediment samples with elevation in boring 1 at site C.
62
-------
At site B, significant positive correlations with sample elevation were
observed with cyanide, total organic carbon, iron, sodium, boron, chromium,
and zinc. A positive correlation is expected for constituents derived from
the landfill. The control holes showed significant correlations with depth
only for total organic carbon and sodium. Both of these correlations were
negative indicating these constituents were being leached away in a normal
weathering situation.
Calcium at site B showed a significant negative correlation with sample
elevation in borings under the landfill. Calcium is probably being leached
away or is forming less soluble compounds under the landfill. In control
holes both significant positive and negative correlations with depth are found.
At site C, zinc showed a significant negative correlation with elevation
under the landfill indicating that it is becoming more available with increasing
depth. Control holes indicated no significant relationship in zinc content
between water extracts and elevation. Calcium showed a positive correlation
with elevation in one of the holes through the landfill and a nagative correla-
tion in a second hole indicating there may be both an increase and decrease
in clacium availability under the landfill. This may be due to the variation
in the age or character of refuse placed in different parts of the landfill.
No significant relationship between sample depth and calcium concentration in
water extracts could be seen in the control holes.
Patterns observed in the composition of distilled water extracts for
samples taken from these landfill areas indicate that the availability of
total organic carbon, iron, sodium, boron, and chromium to contacting waters
increases under a landfill. The availability of calcium generally decreases
under the landfill at site C.
Griffin and others (15) demonstrated that municipal leachate can remove
calcium from clays. Calcium was the major exchangeable cation present in the
clays used in their experimental leachate attenuation system and was displaced
by other cations from the leachate such as sodium, or ammonium ion. The
calcium level was higher in the effluent coming out of the clays than in the
original leachate. Municipal leachate is mildly acid and contains carbon
dioxide in solution. Calcium in the soil in the form of carbonate could be
taken directly into solution by the leachate and removed from the soil below
the refuse.
Horizontal Variation in Distilled Water Extracts of
Sediment/Soil Samples Near the Water Table
According to the model for leachate movement under a landfill (Figure 1)
horizontal movement of contaminants takes place below the water table. The
model suggests that upgradient samples should have low levels of contamination.
The highest levels of contamination should occur below the landfill, and a
gradual decrease should occur down the groundwater gradient from the landfill.
The decrease in contaminant concentration is related to the dilution effects
of the groundwater and the filtration and adsorption in the soil/sediment.
The distilled water extracts measure availability of the chemical constituents
63
-------
to contacting water. The concentration of any constituent in the distilled
water extract depends not only on the amount of contaminant present; but also
on the solubility of the contaminant under the pH and redox conditions present
in the soil/sediment sample. Chemical analyses of distilled water extracts
of soil samples collected near the existing water table were examined to deter-
mine if any pattern of contaminant distribution in the extracts could be
related to the direction of movement of groundwater.
The number of samples available at each site was too small to allow the
use of analysis of variance. Graphs showing concentration of various con-
stituents versus relative position of the boring with respect to the landfill
are given in Figures 19-21.
At site A, maximum levels for sulfate, nitrite, total organic carbon
(TOC), calcium, magnesium, sodium, arsenic, cadmium, nickel and zinc occurred
in distilled water extracts taken from samples under the landfill. The
amounts available decreased down the groundwater flow gradients. This is the
pattern expected for materials added from the refuse. Manganese levels were
below detection limits under the landfill at site A and increased downgradient
from the landfill. The unusually low levels of manganese below the landfill
may be related to its chemical reduction to the soluble manganous ion and its
loss into water percolating through the soil.
At site B, maximum levels for sulfate, cyanide, TOC, iron, manganese,
boron and chromium were observed in distilled water leaches from samples taken
under the landfill. Chloride showed a maximum level in a boring located up-
gradient from the fill. Chloride may be depleted under the fill due to
slightly increased infiltration through the refuse. Calcium, magnesium,
sodium, nickel, lead, and zinc showed maximum levels in the distilled
water leaches in downgradient wells. The maxima observed in downgradient
wells may represent materials transported in the groundwater and deposited in
surrounding soil.
At site C, the maximum levels for nitrate, TOC, calcium, iron, magnesium,
manganese, sodium, and boron were all found in extracts from borings down the
groundwater gradient from the landfill. No maxima were found under the land-
fill. Lead and zinc were both more concentrated in distilled water leaches
from sediment/soil samples obtained from upgradient borings. The high levels
in downgradient holes may represent materials displaced from the landfill and
moved downgradient. Lead and zinc may have been made less soluble in the
sub-landfill and downdip holes by precipitation in some insoluble form such as
sulfide.
There is evidence at sites B and C of displacement of materials from the
area under the refuse down the groundwater flow gradient. In slow flow
through a porous medium such as sediment/soil, some separation of constituents
can be expected due to differing affinities for the solid phases present (clays
carbonates, etc.) and participation in solution/precipitation reactions. Zones
of high concentrations of various contaminants (as seen in water extractions)
may be displaced by this type of chromatographic activity. Recharge events
such as heavy rainfall at the landfill may further add to the uneven pattern
observed in contaminant distribution. The sulfides associated with some of
64
-------
sf
sw
30 r
2O -
10 -
0 t—
NE
sw
060
O40
O20
0
-
-
BDL BDL BDL ^ — —
i t i -~
3 1 6
NE
i
7
006
? o.&«
Z 002
BDL .
. BDL
3OO
2OO
100
0
0.02
0
' ~~~~^ — ^__BDL BDL
3 1 6
BDL
7
Ln
2 -
OO6
0.04
002
-
-
I BDL _,„--
_
3
'" "^~-^^ BDL
1 6
BDL
7
OO6 r
120 I
080
0.4O
0 I
UNDER
LANDFILL
DOWN
DIP
WELL BORING NUMBERS
UNDER
LANDFILL
Figure 19. Horizontal variation in chemical composition of distilled water extracts at site A.
BDL indicates below detection limits.
-------
30
20
10
0
BDL
SE
BDL
NW
1.20
0.80
O.40
0
BDL
St
0.02
E z
. o
o
*
a
o
I
12
60
40
20
0
BDL
1
BDL,
30
20
10
0
0.60
040
0.20
015
Z 010
O05
1.20
O.80
040
0
0.07 r
0.05 p
O.03 p
BDL
1
5
BDL/
I/ 1
3 1
1
7
-
BDL
5
BDL/
3 1
^•^^^_BDL
7
BDL
BDL BDL
UP
DIP
UNDER
LANDFILL
DOWN
DIP
WELL BORING NUMBERS
006 r
0.04 P
O02 p
Or
BDL
5
UP
DIP
™
/
BDL/
i/ i
3 1
UNOER
LANDFILL
°
7
DOWN
DIP
Figure 20. Horizontal variation in chemical composition of distilled water extracts at site B.
BDL indicates below detection limits.
-------
NNW
200
7 8
c
2
SSE
600
400
200
-
-
BDL BDL BDL BDL
NNV
y
, _x
0 78 9632 54
Z
7.O
5.0
3.0
-
1 \ ^-^^-^~ '
/
/
— /
1 1
1 ft 1 1__J 1 1 1 ' • '
10 78 9632 54
a.
t-
z
8
16
12
8
4
rt
-
-
-
-
1 I i 1
7 8
Z
o
a.
003
002
001
ft
-
-
~ BDL BDL
1 1
BDL
1
s^ "
BDL BDL .X
i ^ 1 1
78
t-
UJ
u
u
0.12
._ 008
Z 004
n
-
-
" BDL/^^ BDL
k_J !±aJ
f
/
BDL BDL _-.—0/^
i i i—— 1 1
78
2.40
I 60
0.80
0
78
ND
I
BDL BDL
i I
120
80
40
0
: ^_^
76 9 63
— — t
Z
j
UP DIP UNDER
LANDFILL
/
5 4
DOWN
DIP
WELL BORING NUMBERS
UP DIP
UNDER
LANDFILL
Figure 21. Horizontal variation in chemical composition of distilled water extracts at site C.
BDL indicates below detection limits.
DOWN
DIP
-------
the landfills may also reduce the level of some metals in water extracts below
the concentrations found in sediment/soil samples up the groundwater gradient
from the landfill.
CHEMICAL ANALYSES OF NITRIC ACID EXTRACTS
The goal of the nitric acid digest was to determine the concentration of
pollutants that could be released under the most extreme conditions of weather-
ing. The concentration of materials in the nitric acid digest depends upon:
a) the original constituents in the soil and their reactivity with the
hot acid,
b) the extent to which water-soluble and leachate-soluble materials
have been removed from the soil by solution in rainwater or leachate
and,
c) the solubility in acid of materials which have been precipitated,
filtered or absorbed from the leachate passing through the soil.
The analyses of nitric acid digests are given in Tables 25-30. The analytical
results are expressed in milligrams per kilogram dry weight of sample.
Comparison of Nitric Acid Digests from Beneath and Outside the Landfills
Soil samples from directly below the landfill (experimental samples) and
samples taken at comparable depths outside the landfill (control samples) were
digested in nitric acid and the digests were analyzed for selected cations.
Care was taken to select samples outside the landfill that were above the water
table so that the samples were not contaminated by horizontal movement of
leachate from the landfill.
A randomization test was used to evaluate the significance of any differ-
ences in means observed between experimental samples and control samples.
This procedure was used to avoid the assumption of normal distribution and
homogeneous variance required by the more commonly used t-test. With the
small sample size, five samples at each site, the highest level of significance
that could be assigned to a two-tailed, randomization test was 80%. The
results of the randomization tests are presented in Table 31.
In the majority of cases, the nitric acid digests of soil samples from
below the landfills showed higher metal content than the nitric acid digest
of soil outside the landfills. The increased metal content in the soil
represents material filtered, absorbed or precipitated from the leachate (i.e.
attenuated) on its contact with the sub-landfill soil.
At site A, significant differences in concentration in the acid digests
of samples beneath and outside the landfill occurred with arsenic, boron,
beryllium, nickel and selenium. Boron and beryllium showed higher concentra-
tions in the nitric acid digests from samples taken from below the landfill.
The levels of arsenic, nickel and selenium in the sub-landfill soil were
68
-------
TABLE 25. ANALYSES OF NITRIC ACID DIGESTS OF SOIL SAMPLES FROM EXPERIMENTAL BORINGS AT SITE A
vO
Boring
and sample
Kiev (m)
Depth below
raw/soil
interface (m)
Ht above water
table (m)
Cone, (mg/kg
dry wt)
Fe
Mn
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
1C1
250.57
0.00
18.06
ND
302.25
0.10
2.90
0.07
0.27
2.96
8.06
BDL
5.04
25.19
0.32
17.95
1C2
249.77
0.82
17.24
ND
399.52
0.17
4.10
0.11
0.42
2.73
6.52
BDL
5.57
17.87
0.46
10.93
1C3
247.58
3.02
15.05
ND
444.63
0.15
3.54
0.08
0.35
3.13
8.65
BDL
6.01
26.35
0.53
10.54
1C4
242.08
8.52
9.55
ND
462.02
0.14
2.99
0.09
0.49
2.85
7.34
BDL
6.79
16.31
0.68
7.88
1C5
234.81
15.78
2.28
ND
593.04
0.14
2.10
0.11
0.41
2.58
9.95
BDL
5.93
21.04
0.44
7.36
1C6
230.83
19.77
-1.70
ND
287.36
0.22
2.87
0.30
0.47
5.75
10.54
BDL
6.70
28.74
0.50
11.97
1C 7
230.83
19.77
-1.70
ND
320.14
0.17
1.60
0.09
0.36
2.02
6.74
BDL
4.38
21.90
0.39
8.17
2C1
250.98
0.00
19.97
ND
894.94
0.16
2.07
0.08
0.29
2.96
9.77
BDL
5.23
11.34
0.26
7.44
2C2
250.14
0.84
19.13
ND
374.26
0.14
1.29
0.06
0.28
1.94
5.42
BDL
4.00
12.26
0.40
6.13
2C3
247.99
2.99
16.98
ND
579.75
0.14
1.63
0.07
0.30
2.90
10.99
BDL
5.80
8.48
0.34
7.97
(continued)
-------
TABLE 25. (continued)
Boring
and sample
Elev (m)
Depth below
raw/soil
interface (m)
Ht. above water
table (m)
Cone, (mg/kg
dry wt)
Fe
Mn
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
2C4
243.00
7.99
11.99
ND
340.26
0.14
1.24
0.06
0.24
2.27
6.80
BDL
4.76
9.64
0.27
6.2*
2C5
237.11
13.87
6.10
ND
618.55
0.16
1.29
0.06
0.30
2.45
10.44
BDL
5.54
11.60
0.30
12.50
2C6
232.08
18.90
1.07
ND
366.97
0.16
0.86
0.10
0.22
1.65
8.13
BDL
4.16
10.40
BDL
6.18
3C1
250.53
0.00
19.31
ND
312.12
0.16
1.35
0.11
0.33
2.48
7.38
BDL
5.25
12.77
0.31
36.18
3C2
249.53
1.00
18.31
ND
1015.93
0.47
1.39
0.08
0.32
2.99
7.17
BDL
5.84
11.83
0.31
54.97
3C3
247.60
2.93
16.38
ND
741.15
0.40
1.50
0.07
0.32
3.44
9.75
BDL
6.24
11.70
0.32
7.80
3C4
240.27
10.26
9.05
ND
410.14
0.26
0.75
0.06
0.27
2.61
8.70
BDL
5.59
12.43
0.31
6.84
3C5
235.72
14.81
4.50
ND
356.57
0.28
0.84
0.06
0.28
2.34
9.02
BDL
4.90
10.03
0.28
6.68
3C6
230.73
19.80
-0.49
ND
209.50
0.19
1.00
0.05
0.22
1.86
7.86
BDL
4.00
9.05
0.27
10.23
BDL = Below detection limits.
ND = Not determined.
-------
TABLE 26. ANALYSES OF NITRIC ACID DIGESTS OF SOIL SAMPLES FROM CONTROL BORINGS AT SITE A
Boring
and sample
Kiev (m)
Ht. above water
table (m)
Cone, (mg/kg
dry wt)
Fe
Mn
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
6C1
251.09
19.99
ND
566.29
0.51
1.08
0.06
0.27
2.95
7.83
BDL
5.72
8.43
0.36
7.59
6C2
250.20
19.10
ND
503.83
0.64
1.08
0.07
0.27
3.32
9.76
BDL
6.38
10.85
0.36
8.54
6C3
248.08
16.98
ND
546.34
0.60
1.34
0.07
0.27
3.46
10.26
BDL
6.07
8.92
0.31
17.28
6C4
242.05
10.95
ND
417.92
0.49
0.82
0.07
0.29
2.88
9.59
BDL
6.17
9.59
0.30
8.22
6C5
236.86
5.76
ND
632.26
0.55
0.86
0.07
0.28
3.23
11.46
BDL
6.45
9.87
0.32
9.48
6C6
230.84
-0.26
ND
295.05
0.50
0.72
0.05
0.19
1.79
6.75
BDL
3.84
7.15
0.25
4.52
7C1
250.49
14.97
ND
447.30
0.41
0.95
0.07
0.31
2.78
7.05
BDL
5.96
11.52
0.36
6.78
7C2
250.15
14.63
ND
561.80
0.50
1.24
0.06
0.33
3.66
9.21
BDL
6.73
12.41
0.27
10.06
7C3
247.99
12.47
ND
986.56
0.75
1.50
0.06
0.27
7.52
12.45
BDL
7.28
8.93
0.34
9.67
7C4
242.23
6.71
ND
810.06
0.51
1.29
0.07
0.35
3.86
12.02
BDL
7.91
12.22
0.29
10.22
7C5
236.37
-0.85
ND
72.08
0.26
0.79
0.04
0.30
0.92
0.92
BDL
1.44
6.55
0.43
2.29
7C6
233.32
-2.20
ND
96.42
0.24
0.56
0.05
0.24
0.81
1.67
BDL
1.41
6.00
0.46
1.71
Note: All borings are positioned downdip on the groundwater gradient.
BDL = Below detection limits.
N'D = Not determined.
-------
TABLE 27. ANALYSES OF NITRIC ACID DIGESTS OF SOIL SAMPLES FROM EXPERIMENTAL BORINGS AT SITE B
Boring
and sample
Elev (m)
Depth below
mw/soil
interface (m)
Ht above water
table (m)
Cone, (mg/kg
dry wt)
Fe
Mn
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
1C1
55.93
0.00
1.57
18007.
945.76
4.81
5.63
1.05
0.15
8.78
13.47
0.08
21.56
10.59
2.95
50.54
1C2
54.06
1.87
-0.30
15241.
1443.93
4.30
4.53
1.03
0.54
7.49
12.30
0.08
22.26
9.36
2.95
61.23
2C1
56.77
0.00
5.83
14425.
559.55
5.25
6.96
1.76
0.23
7.46
11.31
0.04
29.23
58.46
2.20
54.28
2C2
55.85
, 0.92
4.91
15552.
450.69
3.84
6.57
1.74
0.21
9.19
9.61
0.03
21.70
8.30
1.52
45.97
2C3
53.72
3.05
2.78
11351.
342.08
2.10
5.14
1.41
0.15
7.60
8.68
0.02
17.87
7.19
1.28
38.47
3C1
56.74
0.00
5.51
17246.
505.12
4.43
8.66
1.70
0.43
8.08
11.55
0.04
22.37
8.66
1.80
57.72
3C2
55.74
1.00
2.51
10028.
343.56
1.75
5.39
1.57
0.19
7.83
10.16
0.05
20.38
7.76
1.94
40.11
3C3
53.50
3.24
0.27
12099.
306.60
1.19
6.78
1.56
0.13
7.60
11.47
0.03
25.33
7.60
1.65
39.28
-------
TABLE 28. ANALYSES OF NITRIC ACID DIGESTS OF SOIL SAMPLES FROM CONTROL BORINGS AT SITE B
Boring
and sample
Elev (m)
5C1
55.28
5C2
54.38
5C3
52.44
6C1
54.26
6C2
53.35
6C3
51.22
7C3
42.00
Ht. above water
table (m)
Position in
groundwater
gradient
Cone, (mg/kg
dry wt)
Fe
Mn
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
1.93
updip
1.03
updip
-0.91
updip
4.11
3.20
updip
updip
1.07
updip
0.10
downdip
13054.
497.27
3.95
7.32
1.77
0.26
7.80
9.88
0.06
29.72
7.73
3.00
42.68
11336.
352.03
3.04
5.55
1.52
0.18
6.62
9.72
0.04
24.58
7.75
2.03
39.26
13214.
233.26
2.46
5.78
1.51
0.16
9.79
9.57
0.03
24.29
7.49
1.12
37.77
12924.
428.78
3.04
5.12
1.46
0.20
6.64
8.01
0.02
23.77
7.60
1.52
35.83
13486.
445.18
3.41
5.54
1.80
0.22
8.48
9.13
0.03
26.90
7.97
0.94
48.00
8692.
113.75
0.89
3.68
1.26
0.25
8.00
9.04
0.03
21.86
6.95
1.44
35.91
4062.
2784.25
BDL
73.73
1.20
0.21
15.00
23.25
BDL
32.12
39.54
BDL
42.23
-------
TABLE 29. ANALYSES OF NITRIC ACID DIGESTS OF SOIL SAMPLES FROM EXPERIMENTAL BORINGS AT SITE C
Boring
and sample
Elev (m)
Depth below
row/soil
interface (m)
Ht. above water
table (m)
Cone, (mg/kg
dry wt)
Fe
Mn
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
1C1
131.41
0.00
4.40
25871.0
869.23
0.52
226.31
1.36
2.08
19.29
40.22
0.03
28.29
21.71
0.57
60.07
1C 2
130.48
0.93
3.47
24824.
585.91
0.72
230.89
1.36
2.22
21.82
34.17
0.05
29.10
21.35
0.50
66.07
1C 3
128.34
3.07
1.33
23065.
431.75
0.48
217.17
1.89
2.12
16.79
45.87
0.02
36.13
18.71
0.39
78.78
2C1
127.46
0.00
0.20
22119.
386.14
0.52
209.19
2.03
2.24
15.42
55.36
0.03
33.94
23.51
0.37
96.69
2C2
126.55
0.91
-0.71
28710.
642.77
0.72
235.07
1.47
1.93
10.65
42.36
0.03
32.93
22.83
0.39
91.21
2C3
124.41
3.05
-2.85
24573.
339.37
0.52
207.82
1.27
1.77
9.59
41.56
0.05
34.03
17.08
0.16
85.41
3C1
125.50
0.00
2.48
27563.
710.84
0.76
232.60
0.90
2.00
9.38
11.12
0.04
10.40
18.09
0.16
31.38
3C2
124.57
0.93
1.55
24723.
409.30
0.77
210.14
0.79
1.74
16.13
31.11
0.04
15.60
17.86
0.37
35.30
3C3
123.20
2.30
0.18
36287.
84.28
0.73
292.87
1.94
2.92
11.36
17.71
0.03
14.79
18.79
0.31
55.79
-------
TABLE 30. ANALYSES OF NITRIC ACID DIGESTS OF SOIL SAMPLES FROM CONTROL BORING AT SITE C
Boring
and sample
Elev (m)
Ht . above
water
table (m)
Position in
groundwater
gradient
Cone, (rag/kg
dry wt)
Fe
Mn
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
St
Zn
6C1
132.46
5.42
Updip
17938.
46.21
1.12
180.68
0.54
1.89
14.10
11.50
0.03
6.63
11.37
0.24
21.25
6C2
131.54
4.50
Updip
22378.
13.90
0.97
337.89
0.66
3.10
19.28
17.67
0.06
7.64
15.12
0.19
24.53
6C3
129.41
2.37
Updip
12745.
20.85
0.49
141.55
1.05
1.60
7.87
24.14
0.05
14.70
11.98
0.23
30.01
6C4
127.88
0.84
Updip
30634.0
160.59
0.75
298.24
2.26
2.96
9.99
46.33
0.02
32.30
22.67
0.21
81.42
6C5
126.06
-0.98
Updip
12124.7
194.73
0.54
102.35
0.84
2.08
10.60
15.22
0.02
19.11
14.07
0.30
49.13
7C4
121.80
0.09
Updip
18140.
121.83
0.81
137.00
0.95
2.12
15.54
21.93
0.01
25.50
12.56
0.15
89.89
8C3
130.14
-0.36
Updip
15277.
231.70
0.53
116.13
1.97
1.90
7.72
15.28
0.01
13.25
13.30
0.16
47.52
9C1
143.47
11.47
Updip
21340.
118.74
1.14
180.03
0.69
2.10
14.01
18.99
0.02
9.47
20.79
0.11
17.56
9C2
142.57
10.57
Updip
20419.
71.71
0.89
182.31
1.05
2.28
10.63
49.95
0.02
14.28
23.82
0.17
17.74
9C3
140.44
8.44
Updip
23658.
110.27
0.41
205 . 84
0.89
2.55
14.63
51.26
0.02
7.42
24.39
0.25
16.77
9C4
136.17
4.17
Updip
22352.
210.50
0.57
211.94
1.10
2.42
8.39
29.37
0.01
7.01
18.24
0.25
13.09
9C5
131.91
-0.09
Updip
15584.
76.39
0.79
122.23
0.92
2.14
5.02
16.58
0.01
5.00
7.94
0.30
11.31
4C6
124.74
-0.66
Downdip
23137.
655.94
0.72
182.29
1.39
2.30
13.79
37.63
0.07
31.78
26.64
0.16
85.69
5C4
126.92
-0.12
Downdip
12719.
149.64
1.49
107.47
1.12
1.50
14.2
63.12
0.02
21.42
11.09
0.29
67.34
-------
TABLE 31. RESULTS OF RANDOMIZATION TEST ON NITRIC ACID DIGESTS OF SOIL
SAMPLES DIRECTLY UNDER THE LANDFILLS AND AT COMPARABLE DEPTHS
OUTSIDE THE LANDFILLS
Parameter
Fe
Mn
As
B
Be
Cd
Cr
Cu
Hg
Ni
Pb
Se
Zn
Site A
ND
NS
S
S
s
NS
NS
NS
N
S
NS
S
NS
Site B
S
S
S
NS
NS
NS
NS
S
NS
NS
S
NS
S
Site C
S
S
S
S
S
NS
NS
NS
S
S
NS
NS
S
S = Significant at 80% level.
NS = Not significant at 80% level.
ND = Not determined.
N = Not detected in any sample.
76
-------
lowered possibly by leaching effects due to the organic acids and chemically
reducing conditions produced by the landfill.
At site B, significant differences in concentrations in acid digests
were found for iron, manganese, arsenic, copper, lead and zinc. All of these
metals showed increased levels in soil beneath the landfill as would be ex-
pected from consideration of the model (Figure 1).
At site C, significant differences were found in the concentration of
iron, manganese, arsenic, boron, beryllium, mercury, nickel and zinc. Only
arsenic showed a decrease in concentration beneath the landfill. Arsenic is
behaving at site C as it did at site A and is being depleted in the soil
immediately below the landfill.
If the number of metals that are found in significantly higher quantities
under a landfill is used as a rough index of attenuation, the sand and gravel
at site A is definitely poorer in attenuation than is the loess clay at site
B or the deep, residual soil at site C. The material at site A would have
both poorer filtering qualities because of its larger grain size and lower
adsorption properties because of the lack of clay minerals.
None of the metals determined was shown to have a significant increase in
the sub-landfill samples at all three sites. Iron, manganese, boron, beryllium
and zinc all showed significant accumulation below the landfills at two of the
three sites. These differences in metal levels probably reflect the differing
composition of leachates at the three sites.
Vertical Variation of Constituents in Nitric Acid Digests of Soil Samples;
For those elements that did show a significant difference in means be-
tween sub-landfill samples and samples from comparable depths outside the
landfill, a test was made for a significant relationship between the concen-
tration of a particular cation and the sample elevation in the borings. The
model of leachate movement requires that those materials derived from the
refuse show a positive correlation with elevation in the borings through the
landfill. Outside the landfill the concentration of these materials in a
nitric acid digest would depend on the prevailing weathering processes. There
could be a positive or negative correlation or no correlation at all between
sample elevation and the concentration of metals. In the model situation soil
constituents that are being dissolved by the landfill leachate should show a
negative correlation with sample elevation for samples from under the landfill.
Outside the landfill, these elements may or may not show any correlation with
sample elevation depending on their response to local weathering processes.
The Spearman rank correlation coefficient was used to judge the
strength of association because this technique could be used with small numbers
of samples where the sample distribution is not known. The results of the
Spearman rank correlation are given in Tables 32-34. Graphs of concentrations
versus sample elevation for all cations that showed statistically significant
correlations in experimental borings are given in Figures 22-34. Significant
correlations in control holes are shown for contrast.
77
-------
TABLE 32. CORRELATION OF CHEMICAL ANALYSES OF NITRIC ACID DIGESTS OF SOIL
SAMPLES WITH SAMPLE ELEVATION AT SITE A
Boring No.
Mn
As
B
Be
Ni
Se
1
NS
NS
SP
NS
NS
NS
Experimental
2
NS
NS
SP
NS
NS
NS
Control
3
NS
NS
NS
SP
NS
NS
6
NS
NS
SP
NS
NS
NS
7
NS
NS
NS
NS
NS
NS
SP = Significant positive correlation at 95% level.
SN = Significant negative correlation at 95% level.
NS = Not significant.
78
-------
TABLE 33. CORRELATION OF CHEMICAL ANALYSES OF NITRIC ACID DIGESTS OF SOIL
SAMPLES WITH SAMPLE ELEVATION AT SITE B
Boring No.
Fe
Mn
As
Cu
Pb
Zn
Experimental
1* 2**
NS
SP
SP
SP
SP
SP
Control
3
NS
SP
SP
NS
SP
SP
5
NS
SP
SP
SP
NS
SP
6
NS
NS
NS
NS
NS
NS
SP = Significant positive correlation at 95% level.
SN = Significant negative correlation at 95% level.
NS = Not significant.
* = No critical confidence level available for this size sample.
** = Due to small sample sizes all tests of significance are at 80% confidence
level.
79
-------
TABLE 34. CORRELATION OF CHEMICAL ANALYSES OF NITRIC ACID DIGESTS OF SOIL
SAMPLES WITH SAMPLE DEPTH AT SITE C
Boring No.
Fe
Mn
As
B
Be
Hg
Ni
Zn
1
SP
SP
NS
NS
NS
NS
SN
SN
Experimental
2
NS
NS
NS
SP
SP
NS
NS
SN
Control
3
NS
SP
NS
NS
NS
NS
NS
SN
6
NS
NS
NS
NS
NS
NS
SN
SN
9
NS
NS
NS
NS
NS
SP
SP
SP
SP * Significant positive correlation at 95% level.
SN = Significant negative correlation at 95% level.
NS = Not significant.
80
-------
0.0
254
B CONCENTRATION, mg/kg DRY WEIGHT
1.0 2.0 3.0 4.0 5.0
250 -
246
z
o
H 242
ui
UJ
236
234
230
LEGEND
o 1
Figure 22. Variation of boron concentration in nitric acid digests of
soil/sediment samples with elevation in borings 1, 2, and 6
at site A. Inverted triangle symbols indicate water table
in each boring.
81
-------
0.00
254
250
246
Z
o
242
UJ
_l
UJ
238
234
230
Be CONCENTRATION, mg/kg DRY WEIGHT
0.02 0.04 0.06 0.08 0.10 0.12
1 1 1 1 1 1 1 1 1 1 1
LEGEND
a 3A
Figure 23. Variation of beryllium concentration in nitric acid digests
of soil/sediment samples with elevation in boring 3 at
site A. Inverted triangle symbol indicates water table.
82
-------
Se CONCENTRATION, mg/kg DRY WEIGHT
0.0 O.I
254
0.2
0.3
0.4
0.5
250
246
6
%
z
o
242
_J
Ul
238
234
LEGEND
A 3A
• 6A
V / V
= = ":==:* l±+=±:-:J=
230
Figure 24.
Variation of selenium concentration in nitric acid digests
of soil/sediment samples with elevation in borings 3 and 6
at site A. Inverted triangle symbols indicate water table
in each boring.
-------
0.0
57
AS
1.0
1
CONCENTRATION, mg/kg DRY
2.0 3.0 4.0
WEIGHT
5.0
LEGEND
o 2B
a 3B
o 5B
Variation of arsenic concentration in nitric acid digests
of soil/sediment samples with elevation in borings 2, 3,
and 5 at site B. Inverted triangle symbol indicates water
table.
84
-------
0.0
57
56
. 55
z
o
I
u
d 54
53
Cu CONCENTRATION, mg/Kg DRY WEIGHT
2.0 4.0 6.0 8.0 10.0
12.0
LEGEND
o 2B
o 5B
Figure 26. Variation of copper concentration in nitric acid digests of
soil/sediment samples with elevation in borings 2 and 5 at
site B. Inverted triangle symbol indicates water table.
85
-------
57
56
55
z
o
I
UJ
_l
LJ
54
53
Mn CONCENTRATION, mg/kg DRY WEIGHT
100 200 300 400 500
600
LEGEND
o 2B
A 3B
o 5B
52 L
Figure 27. Variation in manganese concentration in nitric acid digests of
soil/sediment samples with elevation in borings 2, 3 and 5 at
site B. Inverted triangle symbol indicates water table.
86
-------
57
0
Pb CONCENTRATION, mg/kg DRY WEIGHT
10 20 30 40 50
60
56
55
Z
g
1
u
_i
Ul
54
53
LEGEND
o2B
A3B
52 L
Figure 28. Variation of lead concentration in nitric acid digests of
soil/sediment samples with elevation in borings 2 and 3 at
site B.
«7
-------
57
Zn CONCENTRATION, mg/kg DRY WEIGHT
10 20 30 40 50
56
Z
O
I
u
53
52L
60
LEGEND
o 2B
A 3B
o 5B
Figure 29. Variation of zinc concentration in nitric acid digests of
soil/sediment samples with elevation in borings 2, 3, and 5
at site B. Inverted triangle symbol indicates water table.
88
-------
146
Be CONCENTRATION , mg/kg DRY WEIGHT
0.0 0.5 I.O 1.5 2.0 2.5
142
138
z
g
I
LL)
_J
LJ
134
130
126
122
LEGEND
o 2C
Figure 30. Variation of beryllium concentration in nitric acid digests
of soil/sediment samples with elevation in boring 2 at site C.
Inverted triangle symbol indicates water table.
89
-------
146
Fe CONCENTRATION, mg/kg DRY WEIGHT
0 10000 20000 3000O
1 1 1 1 1 1
142
LEGEND
136
e
z"
o
UJ
130
126
o 1C
122 L
Figure 31, Variation of iron concentration in nitric acid digests of
soil/sediment samples with elevation in boring 1 at site C.
90
-------
146
MO CONCENTRATION, mg/kg DRY WEIGHT
0 200 400 600 800 1000
142
138
z
o
£134
LJ
LJ
130
126
122 L
LEGEND
o 1C
a 3C
Figure 32. Variation in manganese concentration in nitric acid dige
of soil/sediment samples with elevation in borings 1 and
at site C.
-------
146
Ni CONCENTRATION, mg/kg DRY WEIGHT
0 10 20 30 40 50
142
138
E
z"
o
I
kl
Ul
134
130
126
LEGEND
D 1C
• 6C
A 9C
122 L
Figure 33.
Variation of nickel concentration in nitric acid digests of
soil/sediment samples with elevation in borings 1, 6 and 9 at
site C. Inverted triangle symbols indicate water table in
each boring.
92
-------
I4S
Zn CONCENTRATION, mg/kg DRY WEIGHT
20 40 60 80
100
142
138
LEGEND
o 1C
o 2C
A 3C
• 6C
A 9C
•z.
o
I
u
LJ
134
130
126
122 L
Figure 34.
Variation of zinc concentration in nitric acid digests of soil/
sediment samples with elevation in borings 1, 2, 3, 6 and 9 at
site C. Inverted triangle symbols indicate water table in each
boring.
93
-------
At site A, boron and beryllium showed significant positive correlations
with elevation. This correlation, together with their increased abundance
under the fill suggests they are being added to the soil by landfill leachate.
Selenium shows a positive correlation with elevation, but is not as abundant
under the fill as outside the fill. This suggests selenium does leach down
from the landfill but is being moved out and is not being held by the soil.
At site B, manganese, arsenic, copper, lead and zinc all showed signifi-
cant positive correlations with sample elevation. The positive correlations
together with the increased levels occurring under the landfill suggest that
these constituents are being added to the soil under the landfill and are
being retained.
At site C, iron, manganese, and beryllium showed significant positive
correlations with sample elevation in borings below the landfill. The increased
concentration of these metals under the landfill and the increasing concentra-
tions upward suggest these metals are being leached from the landfill and held
by the sub-landfill soil. Nickel and zinc showed a significantly larger concen-
tration of metal under the landfill; but an increasing concentration downward
suggests they are leaching from sub-refuse soil.
The ability of landfills to generate metal-rich leachates and the capa-
city of soils to retain these metals varies greatly from site to site. For
the three sites studied, iron, manganese, arsenic, boron, beryllium, copp'er,
lead, selenium and zinc all showed evidence of being derived from the land-
fills. Selenium, while it did appear to be most available immediately below
the landfill at site A, was present in the samples in concentrations below
that seen in surrounding soils of comparable depths indicating it was being
leached from the landfill; but not being held by soil effectively. At site C,
there is an indication that zinc and nickel were present in larger quantities
under the landfill than in the area outside the landfill; but both metals
showed increasing concentration with increasing depth suggesting they are
being moved down into the soil.
Horizontal Variation in Nitric Acid Digests of Sediment/Soil Samples
Near the Water Table
The model developed-for leachate movement indicates that the major hori-
zontal movement of contaminants from leachate takes place below the water
table. If a contaminant is being added to the local soil or sediment by the
landfill the highest concentrations should be in the soil below the landfill.
Lower concentrations should be found in soil below the water table down the
groundwater gradient from the landfill. This decrease in concentration is
related to the filtration, absorption or precipitation occurring in the soil
or sediment as the groundwater flow moves the leachate away from the landfill.
Samples of geologic materials (sediments or soils) were digested to determine
if any pattern of contaminant concentration could be related to the direction
of movement of groundwater.
At site A, the samples collected near the water table in borings 6 and 7
(downgradient) are from a sandstone unit below the glacial valley-fill
material thus some influence of the changing nature of the sediment may be
94
-------
expected in these acid digests. At site C, one sample taken upgradient (boring
4) and one sample taken downgradient (boring 7) were taken from the surface
of the underlying schist. Digests from this less-weathered metamorphic rock
would be expected to differ considerable from that of the soil produced by
the weathering of the rock. At these two sites some reservations must be
taken with regard to interpreting the variation in chemistry as due solely to
the influence of the landfill.
The small number of samples precluded use of statistical comparison tech-
niques. Graphs showing the concentration of various metals versus the relative
positions of the borings with respect to the landfill are given in Figures 35-37.
At site A, maximum concentrations of manganese, boron, cadmium, chromium,
copper, nickel, lead, selenium and zinc occurred in samples taken under the
landfill- Samples taken at or near the water table downdip showed decreasing
amounts of these constituents. Arsenic is the only contaminant that showed a
maximum concentration in a downdip boring.
At site B, iron, arsenic, beryllium, cadmium, mercury, selenium and zinc
all reached maximum concentrations in samples collected under the landfill.
M neanese, boron, chromium, copper, nickel and lead all reach maximum concen-
trations in borings downdip from the landfill.
At site C, iron, boron, cadmium, nickel, selenium, and zinc all reached
Aximum concentrations in samples collected under the landfill. Manganese,
enic, copper, mercury and lead all reached maximum concentrations in
"nles collected downdip from the landfill. Beryllium and chromium were
f nd in their greatest concentrations in samples taken updip from the landfill.
A pattern can be observed in the location of concentration maxima. At
1 three sites the maximum concentration of arsenic is displayed downdip.
two sites (B and C) maximum concentrations for manganese, copper and lead
were found in downdip borings.
DISCUSSION
Physical testing showed no. consistent attribute in the soil/sediment
1 collected at the landfill sites that could be related to the presence
landfilled refuse. There was no detectable change in density, permea-
grain size distribution or water content that could be shewn to be
esponse to the movement of leachate. Griffin and others (15) showed that
Vi neeS in permeability could be observed in experimental columns filled with
1 v and then subjected to landfill leachate. Permeability changes that
red probably involved a relatively small volume of the soil at the very
of the soil column. However, in this investigation, field conditions did
*-°" aivays permit recovery of the sample which included only the interface
the refuse and soi 1 /sod intent .
Extending the model, the flicMiiic.il behavior of contaminants in soil under
, i conditions can be broken into three basic typos of interact ions: flow
^ oo«h attenu.-it ion and mob i 1 i /a t i on . Flow through is essentially (hat
-------
300
200
IOO
0
600
400
2.00
0
g.
-------
3
u
NW
35
15
SE
z
o
L>
7J
50
25
0
z
o
o.io
005
o
32
ae
24
20
60
40
Z 0-
080 f
060 (-
040
oao
o
WELL BORING NUMBERS
60
50
40
30
UP
DIP
UNDER
LANDf ILL
DOWN
DIP
Figure 36. Horizontal variation in chemical composition of nitric acid digests at site B. BDL
indicates below detection limits.
-------
40O ,
300 j-
200 (-
IOO '•—
200 ;
150 r
100 •
050 ;—
400 [
3OO i
l-
20O >
100 t-
7 8
7 8
7 8
6 3
6 3
5 4
5 4
E Z
u
Z
o
30
20
10
0
7 8
7 8
7 8
7 8
6 3
6 3
5 4
5 4
6 3
5 4
15
10
5 •
7 8
UP DIP
6 3
UNDER
LANDFILL
5 4
DOWN
DIP
WELL BORING NUMBERS
UNDER
LANDFILL
DOWN
DIP
Figure 37. Horizontal variation in chemical composition of nitric acid digests at site C.
-------
where negligible chemical interaction takes place. The porous matrix (soil)
is inert and does not effectively filter, absorb or precipitate the contami-
nants. Therefore, no changes can be detected in the composition of the soil.
Cases in which the difference in concentration of contaminants in the nitric
acid digests of the soil samples varied less than 25% between samples inside
the landfill and outside were judged to be examples of "flow through".
The instances of "flow through" are indicated in Table 35 (samples marked "X"
in nitric acid digest column). At all three sites cadmium and chromium had
essentially the same concentrations in the nitric acid digests of soil inside
and outside the landfill. Similarly, nickel (sites A and B), boron (sites B
and C), selenium (sites A and B), beryllium (site B), copper (site A), manganese
(site A) and mercury (site A) were found in equal concentrations. In most
of these cases, the metals are also found in higher concentrations in ground-
water collected under the refuse as would be expected. Earlier investigations
(15) have indicated that attenuation should be effective in removing toxic
metals, the analyses of soil digests given here do not demonstrate a trapping
mechanism for most contaminants.
A second type of interaction takes place when the soil removes contaminants
by filtration, absorption and/or precipitation. The ability of soil to atten-
uate contaminants in this manner is limited by the capacity of the soil to con-
tain pollutants. Up to the time when the capacity is reached, the amount of
contaminant in the soil increases while the amount passing through to the
groundwater is lessened (Table 35). Therefore, the nitric acid digest analyses
should show higher levels of contaminants under the refuse and the concentra-
tions in groundwater under and outside the landfill should be nearly equal.
After the capacity of the soil for attenuating the contaminant has been reached,
concentrations of these contaminants in the groundwater should increase.
Examples of attenuation where soil capacity has not been reached and
groundwater concentrations have not increased are beryllium (sites A and C),
arsenic (site A), copper (site B) and mercury (site C). Examples of cases
where the capacity of the soil to attenuate the contaminant has been reached
or exceeded (concentrations in the groundwater have increased under the
refuse) are zinc (all three sites), iron and manganese (sites B and C), lead
(sites A and C), arsenic (site B), boron (site A) and nickel (site C).
The third possible interaction is the mobilization of soil constituents
by the acids typically occurring in the leachate from the refuse. This action
brings materials into solution that would normally remain fixed in the soil
and brings about a lower concentration of the material in the nitric acid
digests of the soil samples from under the landfill when compared with those
outside the landfill (Table 35). Only arsenic at site C showed a distribution
pattern in the nitric acid digest and the groundwater that would indicate
mobilization is occurring.
In some of the samples where attenuation was indicated, this trend was
further substantiated by the decreased extractabiIity (into distilled water)
observed in samples collected underneath the landfill. While this decreased
extractability was not observed in all cases, it might be a useful indicator
of the formation of highly insoluble phases during attenuation.
-------
TABLE 35.
O
o
Chemical
constituents
Groundwater
Site A
distilled*
water extract
Site B
distilled
water extract
HNO,
Site C
distilled
water extract
>125% of average control sample.
X - 75% to 125% of average control sample.
- - <75% of average control sample.
BDL - More than one half samples below detection limits.
ND = Not determined.
* Note that soil samples used in averages were those at the
HNO,
-------
If the number of metals found in greater abundance in the nitric acid
digest from samples taken directly under the landfill is used as an index of
overall attenuation; site C shows the most active attenuation. Site B and
site A rank second and third respectively, although they are nearly identical.
The character of the soil/sediment in the area of attenuation and the
chemical activity within the refuse leachate appear to be of prime importance
in the attenuation process. In the present study, the poorest attenuation
was associated with an older site having coarse sandy material under the land-
fill. The most effective attenuation appears in a landfill that is relatively
young and underlain by fine-grained material. The high rate of microbial
activity associated with this younger landfill should produce a large quantity
of hydrogen sulfide in the leachate and precipitate the chalcophile elements
(i.e., those having an affinity for sulfur) such as iron, nickel, copper, zinc,
mercury and lead.
101
-------
REFERENCES
1. Schneider, W. J. Hydrologic Implications of Solid-Waste Disposal. Circ.
601-F, U. S. Geol. Surv., Washington D. C., 1970. 10 pp.
2. Garland, G. A. and D. C. Mosher. Leachate Effects of Improper Land Dis-
posal. Waste Age, March 1975. pp. 42-48.
3. Exler, H. J. Defining the Spread of Groundwater Contamination Below a
Waste Tip. In: Ground Water Pollution in Europe, J. A. Cole, ed.
Water Information Center, Port Washington, New York, 1974. pp. 215-241.
4. Hughes, G. M., R. A. Landon, and R. N. Farvolden. Hydrogeology of Solid
Wastes Disposal Sites in Northeastern Illinois. Solid Waste Report
SW-12d, U. S. Environmental Protection Agency, Washington, D. C., 1971.
154 pp.
5. Qasim, S. R. and J. C. Burchinal. Leaching from Simulated Landfills.
J. Water Pollution Control Fed. 42 (3, pt. 1): 371-379, 1970.
6. U. S. Army Engineer, Waterways Experiment Station. The Unified Soil
Classification System. Tech. Memorandum No. 3-257, Vol. 1, USAE Water-
ways Experiment Station, Vicksburg, Mississippi, 1960. 30 pp.
7. Levinson, A. A. Introduction to Exploration Geochemistry. Applied
Publ. Co. Ltd. Calgory, Canada, 1974. 612 pp.
8. Ward, F. N., H. M. Nakagawa, T. F. Harms, and G. H. VanSickle. Atomic
Absorption Methods of Analysis Useful in Geochemical Exploration. Bull.
1289, U. S. Geol. Surv., Washington, D. C., 1969. 45 pp.
9. Foster, J. R. The Reduction of Matrix Effects in Atomic Absorption
Analysis and the Efficiency of Selected Extractions on Rock Forming
Minerals. In: Geochemical Exploration, The Canadian Institute of Mining
and Metallurgy. Special Vol. 11, Ottawa, Canada, 1971. pp. 554-560.
10. U. S. Dept. of the Army. Laboratory Soils Testing Engineering Manual
EM 1110-2-1906, U. S. Dept. of the Army, Washington, D. C., 1970. No
pagination.
11. U. S. Environmental Protection Agency. Manual of Methods of Chemical
Analyses of Water and Wastes. EPA 625/6-74-003, U. S. Environmental
Protection Agency, Cincinnati, Ohio, 1971. 298 pp.
102
-------
12. Siegel, Sidney. Nonparameteric Statistics for the Behavioral Sciences.
McGraw-Hill Book Co., New York, 1956. 312 pp.
13. Siddiqui, and R. R. Parizek. Application of Nonparametric Statistical
Tests in Hydrogeology. Groundwater, 10(2):26-31, 1972.
14. Palmquist, R. and L. V. A. Sendlein. The Configuration of Contaminated
Enclaves from Refuse Disposal Sites on Floodplains. Groundwater, 13(2):
167-181, 1975.
15. Griffin, R. A. and others. Attenuation of Pollutants in Landfill Leachate
by Clay Minerals. Environmental Geology Notes No. 78, Illinois Geological
Survey, Urbana, Illinois, 1976. 34 pp.
103
-------
APPENDIX A
SUB-SURFACE INFORMATION FOR SITE A
104
-------
LEGEND
WELL LOCATION
Figure A-l.
Water table map of site A (contour lines are elevation of water table in feet above mean
sea level). 0.305 m = 1 ft.
-------
TABLE A-l. LOG OF BORING 1 AT SITE A
Elevation above MSL*
(m)
257.96 - 257.29
257.29 - 250.76
250.76 - 247.08
247.08 - 235.58
235.58 - 232.53
232.53 - 229.88
Depth (m) Description
0.0 - 0.67 Cover material (sand with some large
gravel)
0.67 - 7.20 Fill
7.20 - 10.88 Sand (SP) medium, light
traces of small gravel
10.88 - 22.38 Sand (SP) medium, light
brown with
brown
22.38 - 25.43 Sand (SP) medium to coarse tan with.
scattered gravel
25.43 - 28.08 Sand (SP) fine, tan with
streaks
orange
* MSL = mean sea level
Water table elevation above MSL = 232.53 m
106
-------
TABLE A-2. LOG OF BORING 2 AT SITE A
Elevation above MSL*
(m) Depth (m) Description
257.00 - 255.78 0.0 - 1.22 Cover material (sand (SP)) medium to
coarse, some gravel
255.78 - 251.24 1.22 - 5.76 Waste
251.24 - 250.32 5.76 - 6.68 Sand (SP) medium, light brown
250.32 - 247.58 6.68 - 9.42 Sand (SP) medium to coarse, light
brown with gravel
247.58 - 230.5 9.42 - 26.50 Sand (SP) medium to coarse light
brown with gravel
Water table elevation above MSL = 231.01 m
107
-------
TABLE A-3. LOG OF BORING 3 AT SITE A
Elevation above MSL
(m) Depth (m) Description
258.57 - 255.52 0.0 - 3.05 Cover material (sand (SP)) medium to
coarse brown
255.52 - 250.71 3.05 - 7.86 Fill
250.71 - 236.31 7.86 - 22.26 Sand (SP), medium to coarse, brown
with gravel
236.31 - 229.97 22.26 - 28.60 Gravely sand (SP) medium to coarse,
brown
Water table elevation above MSL * 231.22 m
108
-------
TABLE A-4. LOG OF BORING 4 AT SITE A
Elevation above MSL
(m) Depth (m) Description
253.60 - 249.49 0.0 - 4.11 Sand (SP) medium to coarse, light
brown
249.49 - 247.35 4.11 - 6.25 Sand (SP) medium, brown with some
gravel
247.35 - 242.78 6.25 - 10.82 Sand (SP) fine to medium, light brown
242.78 - 241.80 10.82 - 11.80 Sandy gravel (GP), light brown
241.80 - 236.99 11.80 - 16.61 Sand (SP) medium to coarse, light
brown with some gravel
236.99 - 236.38 16.61 - 17.22 Sandy gravel (GP), light brown
236.38 - 230.12 17.22 - 23.48 Gravelly sand (SP), medium to coarse
-^—
Water table elevation above MSL - 230.91 m
109
-------
TABLE A-5. LOG OF BORING 5 AT SITE A
Elevation above MSL
(m) Depth (m) Description
255.02 - 241.91 0.0 - 13.11 Sand (SP), medium to coarse, light
brown with gravel
241.91 - 237.18 13.11 - 17.84 Sand (SP) , medium to coarse, light
brown
237.18 - 236.57 17.84 - 18.45 Gravelly sand (SP), brown
236.57 - 236.06 18.45 - 18.96 Sand (SP), medium to coarse, light
brown
236.06 - 231.24 18.96 - 23.78 Sand (SP), medium to coarse, light
brown with gravel
231.24 - 230.23 23.78 - 24.79 Sand (SP), medium to coarse, brown
Water table elevation above MSL * 231.10 m
110
-------
TABLE A-6. LOG OF BORING 6 AT SITE A
Elevation above MSL
(m) Depth (m) Description
256.01 - 255.77 0.0 - 0.24 Sand (SP) fine-medium, dark brown
255.77 - 254.33 0.24 - 1.68 Sand (SP), fine-medium, brown
254.33 - 242.23 1.68 - 13.78 Sand (SP) medium-coarse, brown with
gravel
242.23 - 232.08 13.78 - 23.93 Sand (SP), medium-coarse, light brown
scattered small gravel
232.08 - 231.47 23.43 - 24.54 Gravelly sand (SP), brown
231.47 - 231.16 24.54 - 24.85 Sand (SP) , medium-coarse, light brown,
with gravel
231.16 - 231.10 24.85 - 24.91 Sandstone, tan
231.10 - 229.95 24.91 - 26.06 Sand (SP), medium, brown
Water table elevation above MSL =•= 231.10 m
I I
-------
TABLE A-7. LOG OF BORING 7 AT SITE A
Elevation above MSL
(m)
255.
254.
252.
64 -
73 -
60 -
254.
252.
250.
73
60
82
Depth
0.
0.
3.
0 -
91 -
04 -
(m)
0.
3.
4.
Description
91
04
82
Sand
Sand
Sand
(SP)
(SP)
(SP)
, fine-medium,
, fine-medium,
, coarse, light
dark brown
brown
brown with
gravel
250.
250.
82 -
30 -
250.
247.
30
16
4.
5.
82 -
34 -
5.
8.
34
48
Sand
(SP)
Gravelly
, medium-coarse
, light brown
sand (SP) , medium-coarse,
brown
247.16 - 240.40 - 8.48 - 15.24 Sand (SP), medium-coarse, brown with
gravel
240
238
237
235
.40 -
.87 -
.20 -
.52 -
238
237
235
233
.87
.20
.52
.08
15
16
18
20
.24 -
.77 -
.44 -
.12 -
16.
18.
20.
22.
77
44
12
56
Sandy gravel (GP) ,
brown
Sand (SP) , medium-coarse, light
with gravel
Sandstone, tan
Sand, fine-medium,
light brown
brown
Water table elevation above MSL = 235.52 m
112
-------
TABLE A-8. LOG OF BORING 8 AT SITE A
Elevation above MSL
(m) Depth (m) Description
265.04 - 264.28 0.0 - 0.76 Sand (SP) , fine, dark brown
264.28 - 264.13 0.76 - 0.91 Sand (SP) , medium, brown with gravel
264.13 - 258.94 0.91 - 6.10 Sand (SP) , coarse, brown with gravel
258.94 - 249.10 6.10 - 15.94 Sand (SP), medium-coarse, brown, trace
of gravel
249.10 - 242.18 15.94 - 22.86 Sand (SP) , medium-coarse, brown, with
gravel
242.18 - 241.72 22.86 - 23.32 Sandy gravel (GP), brown
241.72 - 231.35 23.32 - 33.69 Sand (SP), medium-coarse, brown with
gravel
231.35 - 230.34 33.69 - 34.7 Sand (SP) , medium-coarse, light brown
Water table elevation above MSL » 235.52 m
113
-------
A-9. LIST OF SAMPLES EXAMINED FROM SITE A
•-•--—•• - - — •- — _ _
Elevation
of Elevation Thickness Thickness Elevation
top of of Total of of MW/soil Sampled depth
hole water table depth cover refuse interface interval (m)
Boring (m) (m) (m) (m) (m) (m) From To
1 257.96 232.53 28.26 0.67 6.52 250.77 7.20
7.37
8.19
10.38
10.94
15.88
22.65
23.15
27.13
27.13
2 257.01 231.01 29.52 1.22 4.85 250.94 6.03
6.25
6.87
6.92
8.81
9.02
13.87
14.01
19.51
19.90
24.39
24.93
3 258.57 231.22 31.80 3.05 4.82 250.70 7.86
8.04
9.04
7.70
11,64
22.84
6.68
7.44
9.42
14.39
19.87
24.94
8.32
Elevation of
sampled
intervals (m) Type of
From To sample
250.76
250.59
249.77
247.58
247.02
242.08
235.31
234.81
230.83
230.83
250.98
250.76
250.14
250.09
248.20
247.99
243.14
243.00
237.50
237.11
232.62
232.08
250.71
250.53
249.53
250.26 physical
chemical
chemical
chemical
246.32 physical
chemical
235.12 physical
chemical
chemical
chemical
chemical
250.33 physical
chemical
249.57 physical
249.59 physical
chemical
242.62 physical
chemical
237.14 physical
chemical
232.07 physical
chemical
250.25 physical
chemical
chemical
Sample
number
1C1
1C2
1C3
1C4
1P1
1C5
1P2
1C6
1C7
1C8
2C1
2P1
2C2
2P2
2P3
2C3
2P4
2C4
2P5
2C5
2P6
2C6
3P1
3C1
3C2
(continued)
-------
TABLE A-9. (continued)
Elevation
of Elevation Thickness Thickness Elevation
t0p Of of Total of of MW/soil Sampled depth
hole water table depth cover refuse interface interval(m)
Boring (m) (m) (m) (m) (m) (m) From To
10.
17.
18.
22.
22.
27.
4 253.60 230.91 23.48 NA NA NA 3.
6.
5 257.15 231.10 24.79 NA NA NA 4.
18.
6 256.01 231.10 26.06 NA NA NA 4.
4.
5.
7.
7.
13.
19.
19.
25.
7 255.64 235.52 22.56 NA NA NA 4.
5.
7.
7.
13.
82
97
30
25
85
84
20
25
57
62
44
72
92
81
77
93
96
00
15
17
42
15
49
65
77
26
11.
22.
3.
6.
5.
8.
18.
5.
8.
19.
4.
8.
13.
25
53
90
62
29
20
83
33
42
48
76
26
75
Elevation of
sampled
intervals (m)
From To
247
240
240
236
235
230
250
247
252
249
238
251
251
250
248
248
242
237
236
230
251
250
250
247
247
242
.75
.60
.27
.32
.72
.73
.4
.35
.58
.53
.71
.29
.09
.20
.24
.08
.05
.01
.86
.84
.22
.44
.15
.99
.87
.38
247.
236.
249.
246.
251.
248.
238.
250.
247.
236.
250.
247.
241.
32
04
7
98
86
95
32
69
59
53
88
38
89
Type of
sample
physical
chemical
chemical
physical
chemical
chemical
physical
physical
physical
physical
physical
physica
chemical
chemical
physical
chemical
chemical
physical
chemical
chemical
physical
chemical
chemical
chemical
physical
physical
Sample
number
3P2
3C3
3C4
3P3
3C5
3C6
4P1
4P2
5P1
5P2
5P3
6P1
6C1
6C2
6P2
6C3
6C4
6P3
6C5
6C6
7P1
7C1
7C2
7C3
7P2
7P3
(continued)
-------
TABLE A-9. (concluded)
Elevation
of
top of
hole
Boring (m)
8 265.04
Elevation Thickness Thickness Elevation
of Total of of MW/soil
water table depth cover refuse interface
(m) (m) (m) (m) (m)
231.37 34.70 NA NA NA
Sampled depth
interval (m)
From To
13.41
19.27
22.32
14.32 15.03
17.38 17.96
28.65 28.99
Elevation of
sampled
intervals (m)
From To
242.23
236.37
233.32
250.72 250.01
247.66 247.08
236.39 236.05
Type of
sample
chemical
chemical
chemical
physical
physical
physical
Sample
number
7C4
7C5
7C6
8P1
8P2
8P3
NA * not applicable
-------
APPENDIX B
SUB-SURFACE INFORMATION FOR SITE B
117
-------
00
Figure B-l. Water table map of site B (contour lines are elevation of water table in feet above mean
sea level). 0.305 m = 1 ft.
-------
TABLE B-l. LOG OF BORING 1 AT SITE B
Elevation above
MSL(m)
Depth (m)
Description
60.15 - 54.27
54.27 - 51.74
51.74 - 51.03
0.0 - 5.88
5.88 - 8.41
8.41 - 9.12
Refuse
Clayey silt (ML), gray
Silty clay (CL), gray
Water table elevation above MSL * 54.34 m
-------
TABLE B-2. LOG OF BORING 2 AT SITE B
Elevation above
MSL(m)
57.20 - 57.9
57.90 - 54.46
54.46 - 51.41
51.41 - 48.05
Depth (m) Description
0.0 - 0.30 Backfill
0.30 - 2.74 Refuse
2.74 - 5.79 Clayey silt (ML),
5.79 - 9.15 Clayey silt (ML),
gray
tan
Water table elevation above MSL * 50.94 m
120
-------
TABLE B-3. LOG OF BORING 3 AT SITE B
Elevation above
MSL (m) Depth (m) Description
58.96 - 58.66 0.0 - 0.30 Topsoil
58.66 - 56.74 0.30 - 2.22 Refuse
56.74 - 56.22 2.22 - 2.74 Silt (ML), gray
56.22 - 52.86 2.74 - 6.10 Silt (ML), tan, wet
Water table elevation above MSL - 53.23 m
121
-------
TABLE B-4. LOG OF BORING 4 AT SITE B
Elevation above
MSL (m)
Depth (m)
Description
59.51 - 55.24
55.24 - 51.89
0.0 - 4.27
4.27 - 7.62
Silt (ML), tan
Silt (ML), tan and grayish
tan, wet
Water table elevation above MSL - 53.84 m
122
-------
TABLE B-5. LOG OF BORING 5 AT SITE B
Elevation above
MSL (m)
Depth (m)
Description
62.20 - 57.63
57.63 - 54.58
54.58 - 52.44
0.0 - 4.57
4.57 - 7.62
7.62 - 9.76
Water table elevation above MSL * 53.35 m
Silt (ML), tan
Silt (ML), tan, wet
Silt (ML), tan with gray
specks, wet
i in
-------
TABLE B-6. LOG OF BORING 6 AT SITE B
Elevation above
MSL (m)
Depth (m)
Description
60.52 - 54.42
54.42 - 51.37
51.37 - 49.54
0.0 - 6.10
6.10 - 9.15
9.15 - 10.98
Water table elevation above MSL * 50.15 m
Silt (ML), tan
Silt (ML), tan and gray
Silt (ML), tan with shells
124
-------
TABLE B-7. LOG OF BORING 7 AT SITE B
Elevation above
MSL (m) Depth (m) Description
49.42 - 48.81 0.0 - 0.61 Refuse
48.81 - 45.91 0.61 - 3.51 Silt (ML), gray
45.91-41.80 3.51-7.62 Silt (ML) tan, moist
Water table elevation above MSL =* 42.10 m
125
-------
TABLE B-8. LOG OF BORING 8 AT SITE B
Elevation above
MSL (m)
50.91 - 46.34
46.34 - 43.29
43.29 - 43.08
43.08 - 42.65
Depth (m) Description
0.0 - 4.57 Silt (ML)
4.57 - 7.62 Silt (ML), gray, wet
7.62 - 7.83 Silt (ML), tan
7.83 - 8.26 Silt (ML), light gray with shells
Water table elevation above MSL ~ 45.61 m
126
-------
TABLE B-9. LIST OF SAMPLES EXAMINED FROM SITE B
Elevation
of Elevation Thickness Thickness Elevation
t°F1of of Total °f of MW*/soil Sampled depth
. h°1f water table depth cover refuse interface interval(m)
Borin8 (m> <»> (») (») (m) {») From To
1 60.15 54.36 9.14 0.0 4.88 55.27 4.22
6.09
6.25 6.37
8.41 8.87
2 57.20 50.94 9.14 0.3 2.44 54.46 0.43
1.35
3.48
3.66 4.15
5.79 6.52
3 58.96 53.23 6.10 0.3 1.92 56.74 2.22
3.22
5.46
4 59.51 53.84 7.62 NA NA NA**
5 62.20 53.35 9.76 NA NA NA 0.20
0.92
3.05
6 60.52 50.15 10.98 NA NA NA 5.9
6.10 6.77
7.17
9.15 9.85
9.30
7 49.42 42.10 7.62 0.0 0.61 0.61 4.57 5.27
7.42
'" 50'91 45-61 8.26 NA NA NA 6.10 6.68
* ~ur.ici>al waste
'-' r.-_t *:,:,! icable
Elevation of
sampled
intervals (m)
From To
55.93
54.06
53.90 53.78
51.74 51.28
56.77
55.85
53.72
53.54 53.05
51.41 50.68
56.74
55.74
53.50
—
55.28
54.38
52.44
54.26
54.42 53.75
53.35
51.37 50.67
51.22
44.85 44.15
42.00
44.81 44.23
Type of
Ramp IP
chemical
chemical
physical
physical
chemical
chemical
chemical
physical
physical
chemical
chemical
chemical
__.
chemical
chemical
chemical
chemical
physical
chemical
physical
chemical
physical
chemical
physical
Sample
number
1C1
1C2
1P1
1P2
2C1
2C2
2C3
2P1
2P2
3C1
3C2
3C3
__
5C1
5C2
5C3
6C1
6P1
6C2
6P2
6C3
7P1
7C1
8P1
-- r,; ii.~.:,le selected
-------
APPENDIX C
SUB-SURFACE INFORMATION FOR SITE C
WELL LOCATION
\ V \ \ \ \
Figure C-l. Water table map of site C (contour lines are elevation of
water table in feet above mean sea level). 0.305 m = 1 ft,
128
-------
TABLE C-l. LOG OF BORING 1 AT SITE C
Elevation above MSL*
(m)
157.40-156.49
156.49-131.79
131.79-131.33
131.33-128.38
128.38-124.78
124.78
Depth (m)
0.0 - 0.91
0.91-25.61
25.61-26.07
26.07-29.02
29.02-32.62
32.62
Description
Clay (cover material)
Refuse
Silt (ML), tan
Silt (ML), red
Silty sand (SM) , brown
Schist
* MSL = mean sea level
Water table elevation above MSL = 127.01 m
129
-------
TABLE C-2. LOG OF BORING 2 AT SITE C
Elevation above MSL
(m)
145.85-144.63
144.63-139.75
139.75-137.31
137.31-128.17
128.17-126.64
126.64-123.26
Depth (m)
0.0 - 1.22
1.22- 6.10
6.10- 8.54
8.54-17.68
17.68-19.21
19.21-22.59
Description
Clay (cover material)
Refuse
Saturated fill
Refuse very wet
Silty sand (SM)
Sandy silt (ML)
Water table elevation above MSL - 127.26
130
-------
TABLE C-3. LOG OF BORING 3 AT SITE C
Elevation above MSL
(m) Depth (m) Description
145.58-145.28 0.0 - 0.30 Cover material
145.28-125.61 0.30-19.97 Refuse
125.61-124.70 19.97-20.88 Clayey sandy silt (ML), light
green
124.70-123.32 20,88-22.26 Sandy silt (ML), brown with gravel
123.32-122.72 22.26-22.86 Sandy silt (ML), brown
Water table elevation above MSL = 123.02
m
in
-------
TABLE C-4. LOG OF BORING 4 AT SITE C
Elevation above MSL
Cm)
Depth (m)
Description
136.43-135.39
135.39-130.33
130.33-125.36
125.36-124.91
0.0 - 1.04
1.04- 6.10
6.10-11.07
11.07-11.52
Backfill
Clayey sandy silt (ML), brown
Sandy silt (ML), brown
Highly weathered schist
Water table elevation above MSL = 125.40 m
132
-------
TABLE C-5. LOG OF BORING 5 AT SITE C
Elevation above MSL
(m)
131.61-131.00
131 .-00-130. 09
130.09-127.95
127.95-127.04
127.04-126.31
Depth (m) Description
0.0 -0.61 Backfill
0.61-1.52 Silty clay
1.52-3.66 Silty clay
3.66-4.57 Sandy silt
4.57-5.30 Sandy silt
tan, wet
(CL) , dark gray
(CL) , tan
(ML), red, tan
(ML), red and
Water table elevation above MSL = 127.04 m
133
-------
TABLE C-6. LOG OF BORING 6 AT SITE C
Elevation above MSL
(m)
133.81-132.90
132.90-130.76
130.76-126.71
Depth (m)
0.0 -0.91
0.91-3.05
3.05-7.01
Description
Silty clay (CL) , brown
Clayey sandy silt (ML) , tan
Sandy silt (ML), brown
Water table elevation above MSL = 6.77 m
134
-------
TABLE C-7. LOG OF BORING 7 AT SITE C
Elevation above MSL
(m)
125.27-122.83
122.83-121.92
121.92-121.64
Depth (m) Description
0.0 -2.44 Sandy silt
brown
2.44-3.35 Sandy silt
3.35-3.63 Silty sand
(ML), reddish
(ML) brown, damp
(SM) fine, green
Water table elevation above MSL = 121.71 m
n r>
-------
TABLE C-8. LOG OF BORING 8 AT SITE C
Elevation above MSL
(m)
132.38-131.47
131.47-130.25
130,25-129.18
Depth (m)
0.0 -0.91
0.91-2.13
2.13-3.20
Description
Clayey silt (ML), tan with
Clayey silt (ML), brown
Sandy silt (ML) , brown
gravel
Water table elevation above MSL = 130.55 m
136
-------
TABLE C-9. LOG OF BORING 9 AT SITE C
Elevation above MSL
(m)
145.55-142.70
142.70-133.90
133.90-131.53
Depth (m) Description
0.0 - 3.35 Sandy silt
brown
3.35-11.65 Sandy silt
11.65-14.02 Silty sand
(ML), reddish
(ML) , brown
(SM), brown
Water table elevation above MSL = 131.95 m
137
-------
oc
5
6
TABLE C-10. LIST OF SAMPLES EXAMINED FROM SITE C
145.58
136.46
131.62
133.81
145.85 127.26
125.40
127.04
127.04
22.59
128.17
22.36 0.30
19.66
125.62
52
-.JZ
18
. 1O
7.0!
NA
NA
NA
NA
NA
NA
• •
25.91
28.96
18.29
18.39
19.30
21.44
22.26
19.97
20.08
21.01
22.28
22.47
1.70
8.49
11.72
* -•-** *_ w-i
.
26.36 131.50
130.48
29.40 128.45
128.34
18.96 127.56
127.46
124.' 41
22.59 123.59
20.46 125.61
125.50
124.57
123.20
22.92 123.11
2.03 134.76
8.76 127.97
124.74
131.05 physical
chemical
chemical
128.01 physical
chemical
126.89 physical
chemical
chemical
chemical
122.92 physical
125.12 physical
chemical
chemical
chemical
122.66 physical
134.43 physical
127.70 physical
chemical
Sample
number
— .
1P1
1C1
1C2
1P2
1C3
2P1
2C1
2C2
2C3
2P2
3P1
3C1
3C2
3C3
3P2
4P1
4P2
4C1
i.7
126.92
chemical 5C1
0.91
1.35
2.27
4,40
1.46 132.90
132.46
131.54
129.41
132.35 physical
chemical
chemical
chemical
6P1
6C1
6C2
6C3
(continued)
-------
Boring
TABLE C-10. (continued)
Elevation
of
top of
hole
(m)
125.27
132.38
145.55
Elevation
of
water table
(m)
Thickness Thickness Elevation
. ., of of MW/soil Sampled depth
depth cover refuse interface interval(m)
(m) (m) From To
Elevation of
sampled
intervals (m)
From To
Type of
sample
121.71
4.12 NA
130.50 3.20 NA
132.0 14.02 NA
NA
NA
NA
NA
NA
NA
4.57
5.93
7.75
0.91
3.47
2.24
5.11
1.58
129.24
127.88
126.06
130.14
'•A - not applicable
-'ore: All elevations are given with reference to mean sea level.
Sample
number
128.70 physical 6P2
chemical 6C4
chemical 6C5
124.36 123.69 physical 7P1
121-80 chemical 7C1
chemical 8C1
2.08
2. 98
5.11
7.32
9.38
13.64
143.47
142.57
140.44
7.88 138.23
136.17
131.91
chemical
chemical
chemical
137.67 physical
chemical
chemical
9C1
9C2
9C3
9P1
9C4
9C5
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1 . REPORT NO.
EPA-600/2-78-096
2.
4. TITLE AND SUBTITLE
Chemical and Physical Effects of Municipal I
on Underlying Soils and Groundwater
3. RECIPIENT'S ACCESS1OI>NO.
5. REPORT DATE
anHfilK M^ 1 ™ ( I
ssuing Date)
6. PERFORMING ORGANIZATION CODE
7 AUTHOR(S) 8. PERFORMING ORGAN IZATION REPORT NO.
U.S. Army Engineer Waterways Experiment Station
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Environmental Effects Laboratory
U.S. Army Engineer Waterways Experiment Sta
Vicksburg, Mississippi 39180
12, SPONSORING AGENCV NAME AND ADDRESS
Municipal Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
15. SUPPLEMENTARY NOTES
Robert E. Landreth, Project
10. PROGRAM ELEMENT NO.
1DC618
Hon 11. CONTRACT/GRANT NO.
IAG-D4-0569
13. TYPE OF REPORT AND PERIOD COVERED
—fin. -OH Final, June 1975-December 197R
14. SPONSORING AGENCY CODE
EPA/600/14
Officer, 684-7871
16. ABSTRACT lhree munjcipai landfill sites in the eastern and central United States were
studied to determine the effects of the disposal facilities on surrounding soils and
groundwater . Borings were made up the groundwater gradient, down the groundwater
gradient and through the landfill. Soil and groundwater samples from the test borings
were examined, Groundwater samples were analyzed chemically. Soil samples were testec
physically and distilled water extracts and nitric acid digests of the soils were anal-
yzed chemically. Groundwater samples from under and downgradient from the landfill
showed elevated levels of sulfate in every case. At some sites increased levels nf
nitrate, total organic carbon and cyanide could be related to the presence of the
landfill. No changes in physical characteristics could be related to the presence of
the landfill at any site. No evidence was found in this study to indicate that <;nK
landfill soils seal themselves. Distilled water extracts prepared from soil ?Lninc
showed consistently low levels for all soluble constituents. Generally there Si 6S
more sulfate, chloride, organic carbon, nitrate and high levels of trarp m^taic ?„
extracts of soils from under the landfill than from soils collected at similar deSrhs
outside the landfill. Nitric acid digests of soil samples showed great variahilitt/ ^«
chemical composition. At two of the three sites; iron, manganese, boron berv ,,m
and zmc were found in higher concentrations in nitric acid digests immediately under
hSt nnfnhlc- Tfe Fsuljs
------- |