TAR SANDS LEACHATE STUDY
by
Douglas W. Grosse
Environmental Engineer
and
Linda McGowan
Physical Scientist
U.S. Environmental Protection Agency
Industrial Environmental Research Laboratory
Cincinnati, Ohio 45268
INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
-------
NOTICE
This document has been reviewed in accordance with U.S. Environmental
Protection Agency policy and approved for publication. Mention of trade names
or commercial products does not constitute endorsement or recommendation for
use.
ii
-------
FOREWORD
When energy and material resources are extracted, processed, converted,
and used, the related pollutional impacts on our environment and even on our
health often require that new and increasingly more efficient pollution con-
trol methods be used. The Industrial Environmental Research Laboratory -
Cincinnati (lERL-Ci) assists in developing and demonstrating new and improved
methodologies that will meet these needs both efficiently and economically.
The material presented in this report has been collected from an in-house
research project conducted as an initial effort to establish baseline data from
which later environmental assessment can be made and related pollution control
methods be developed. This information will also pinpoint research gaps so
that priorities for subsequent efforts in this area be defined. Further
information can be obtained from the Industrial Environmental Research
Laboratory.
David G. Stephan
Di rector
Industrial Environmental Research Laboratory
Cincinnati
i i i
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TAR SANDS LEACHATE STUDY
ABSTRACT
The Industrial Environmental Research Laboratory (IERL) of the U.S.
Environmental Protection Agency (EPA) has conducted research to assess the
potential for release of contaminants to ground and surface waters from in-situ
and above-ground processing of western tar sands. The purpose of this effort
is to provide information that will (1) assist Federal and State regulatory
offices in permitting activities, (2) provide the EPA with a data base for
reviewing monitoring plans submitted by developers of the tar sands industry
and (3) support efforts by the Office of Solid Waste (OSW) in establishing
guidelines for the ultimate disposal of solid wastes from tar sands operations.
Such information will assist the development of an environmentally acceptable
tar sands industry.
IV
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CONTENTS
Forward iii
Abstract iv
Figures vi
Tables vii
1. Introduction 1
Asphalt Ridge 1
Characterization .... 4
Recovery of Bitumen . 7
2. Research Protocol 8
Experimental Program . „ 8
Materials and Methods . 8
Tar Sand Cores . 8
EP Toxicity Test 8
ASTM (D-3987) Method 10
Chemical Analysis ... 12
Precision and Accuracy 12
3. Results 13
4. Discussion 26
5. Conclusions 28
References 29
-------
FIGURES
Number Page
1 Location map of major oil-impregnated rock deposits
of Utah 2
2 Geological stratigraphy of Asphalt Ridge 3
3 General geology and oil-impregnated sandstones of
Asphalt Ridge and Asphalt Ridge Northwest, .
Northeastern Uinta Basin, Utah 5
4 Sieve analysis of spent tar sands 9
5 Total suspended solids 14
6 Total organic carbon 15
7 Sulfate 16
8 Alkalinity as CaC03 17
vi
-------
TABLES
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Measurement of Asphalt Ridge .............
Typical Tar Sands Composition (Uinta Basin) . . . . .
Physical Property Analysis of Asphalt Ridge Tar
Laboratory Analyses for Tar Sands Samples
Sulfates . .
Sul fides
Alkalinity as CaC03
Total Suspended Solids ...
Total Organic Carbon Analysis
Water Oualitv Criteria for Priority Pollutants . . . .
Page
. . . . 4
. . . . 4
. . . . 6
. . . . 11
. . . . 18
.... 19
.... 20
.... 20
. . . . 21
.... 22
.... 23
.... 24
.... 25
.... 26
.... 27
vii
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SECTION 1
INTRODUCTION
Oil impregnated sandstone, commonly referred to as tar sands, constitutes
the largest known non-fluid petroleum reserve in North America. The largest
known deposit is the Athabasca deposit located in Alberta, Canada. The first
commercial plant, operated by Great Canadian Oil Sands, Ltd. (6COS) was built
to produce a synthetic crude oil. Approximately 20 million barrels of syn-
thetic crude oil, extracted from tar sands bitumen, are produced per year.
Currently a number of companies and research groups in the United States are
working on processes to recover bitumen from tar sands. The potential for
commercialization of tar sands resources is great, particularly in Utah where
approximately 90-95% of the known tar sands deposits in the United States are
located.(1)
Preliminary studies on assessing the environmental implication of in-situ
extraction, as well as above-ground retorting, are scarce. There is height-
ened concern in states such as Utah regarding the environmental impact on
local water supplies from tar sands mining and in-situ recovery operations.
Water plays an important role in the recovery of tar sands bitumen. The
extent of the pollution problem associated with the water usage has not been
thoroughly examined, .... _.
An in-house research project was conducted by the EPA's Industrial
Environmental Research Laboratory (IERL) at the Test and Evaluation (T&E)
Facility in Cincinnati, Ohio, to provide information concerning the potential
for release of contaminants to groundwater resources from in-situ and above-
ground processing of tar sands. The experimenters conducting this study aim to
examine the composition of the leachate that may be generated from raw tar sand
cores and spent tar sands waste. The Resource Conservation Recovery Act's
(RCRA) Extraction Procedure, (EP) Toxicity Test was used to simulate such a
leachate generation.
Asphalt Ridge
Near surface deposits located in Utah are estimated to contain as much as
29 billion barrels of petroleum, as embedded bitumen in approximately 50 known
groups of deposits in and near the Uinta Basin of northeastern Utah and in the
southeastern portion of the state.(1) With regard to surface extraction oper-
ations, one of the more accessible major deposits in the United States is
located at Asphalt Ridge near Vernal, Utah in the Uinta Basin (3) (see
Figure 1). Tar sands deposits occur in a variety of stratigraphic and struc-
tural circumstances (see Figure 2).(3) The Uinta Basin grouping of deposits
contain petroleum which probably originated in Eocene lacustrine source rocks
of the Green River formation.
-------
HIGH
f(
PLATEAUS
OIL-IMPREGNATED SANDSTONE
DEPOSITS OF UTAH
\ DEPOSITS
Hachures indicate downdip extensions and
buried parts of deposits. Index numbers
to deposits discussed in this paper.
1. ASPHALT RIDGE
2. ASPHALT RIDGE, NORTHWEST
_ 3. P, R. SPRING
4. HILL CREEK
5. SUNNYSIDE
6. TAR SAND TRIANGLE
7. CIRCLE CLIFFS
Figure 1. Location map of oil-impregnated rock deposits of Utah. (3)
-------
ec
i
O
LU I-
o <
Q 5
^5
CO
co o
< P
O
LU
'CO
CO
LU
5
x
i-
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PO
ft
CL
to
•a:
o
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Cr.
-------
Asphalt Ridge has been described as a cuesta which runs in a northwest
direction for approximately 15 miles. The tar sands deposit extends 12 miles
along the strike of the ridge in two sections separated by an "angular non-
conformity" (see Figure 3).(3) These units are comprised of the Mesaverde
group (late Cretaceous), the Uinta and the Duchesne River formations (Eocene-
Oligocene). Within the Mesaverde grouping two formations of marine origin
occur; namely, the Asphalt Ridge and Rim Rock sandstone. The Rim Rock
sandstone formation which exhibits the greatest exposed thickness of oil
impregnation ranges from less than 100 to over 300 feet in thickness. The
Duchesne River Formation (Eocene) of continental origin overlays these strata
with material consisting of conglomerate, sandstone, siltstone and shale.
It is difficult to determine the exact size of the tar sands deposits to
be found at Asphalt Ridge since very little subsurface data is available.
However, assuming that the oil impregnation observed at the surface extends
continuously into the subsurface behind the outcrop, an estimate of approxi-
mately 1.05 billion barrels has been given (see Table 1 below).(3)
TABLE 1. MEASUREMENT OF ASPHALT RIDGE TAR SANDS DEPOSITS
Stratigraphic Unit - Duchesne River Formation Rimrock Sandstone
Oil in place (millions of barrels)
Estimated 1,048
Measured 873
Area! extent (miles2) 20-25
No. of principal pay zones 2-5
Gross thickness (range in feet) 0-500
Characteri zati on
The general composition of Uinta Basin tar sands deposits may be divided
into several categories: bitumen content; water content; porosity and air
permeability (see Table 2). Since bitumen saturation is an important factor in
extracting petroleum from tar sands, lower limits for viable mining operations
have been established. Bitumen content should not be less than 10 (% wt.) for
most mining processes with in-situ processes requiring slightly less. Small
fines content, low water percentage and high permeability of Asphalt Ridge tar
sands make it suitable for bitumen recovery via in-situ processes.(1)
TABLE 2. TYPICAL TAR SANDS COMPOSITION (UINTA BASIN-P.R. SPRING) (1)
Minerals Weight Percent
Sand (44 microns) 90.5
Fines (44 microns) 1.5
Bitumen 7.5
Water 0.5
100.0
Porosity (vol. %) 8.4
Air permeability (millidarcies) 133
4
-------
R.20 E.
R.21 E.
EXPLANATION
Exposures of oil-impregnated sandstone
f.— Geologic contact
T Tertiary strata: Duchesne Rive'
Formation
K Cretaceous strata: Mesavprde Group and
Mancos Shale, undivided
Mantle
N. V^Ashley Valley
\ '. , 'Oil Field
Figure 3. General geology and oil-Impregnated sandstones of Asphalt Ridge
and Asphalt Ridge Northwwest, Northeastern Ulnta Basin, Utah. (3)
-------
Physical property data and elemental analyses for representative Asphalt
Ridge tar sands bitumen were provided by researchers at the Department of
Energy's (DOE) Laramie Energy Technology Center (LETC)(1). The data is
presented in Table 3 below.
TABLE 3. PHYSICAL PROPERTY ANALYSIS OF ASPHALT RIDGE TAR SANDS BITUMENS (1)
Bitumen
Specific gravity . .970
API 14.4
Atomic C/H .606
Molecular weight (Ave.) 668
Viscosity (centipoises, 77°F) 2,950,000
Asphaltenes (wt. %) 3.4
Elemental Analysis (wt.%)
Carbon 85.3
Hydrogen 11.7
Nitrogen 1.0
Sulfur 0.14
Oxygen 1.1
Gross Composition (fraction)
" Acid ' • 10.1
Bases 12.9
Neutral Lewis Bases 19.3
Saturated hydrocarbons 29.3
Aromatic hydrocarbons 28.4
Upon analysis of bitumen properties, it may be noted that API gravities cor-
relate favorably with values associated with petroleum residues. A low
carbon-tohydrogen ratio indicates that Asphalt Ridge bitumens are less aro-
matic than other bitumens (e.g., Athabasca) hence, enhancing bitumen proces-
sing characteristics. Asphaltene content is a measure of the coke-forming
tendency basic to bitumen processing. The high viscosity figure supports the
conclusion that elevated temperatures are necessary to cause bitumens to flow
properly. Asphalt Ridge bitumens seem to exhibit a relatively low sulfur
content which is an important factor in selecting upgrading sequences tor
bitumen processing as well as waste disposal and discharge practices.
Gross bitumen compositions are also presented in Table 3. All figures
were normalized to account for 100% of the bitumen. Functional groups have
been partitioned into several groupings: acids (phenols, carbazoles, and
carboxylic acids), bases (sulfoxides, amides, pyridine and benzologs) and
neutral Lewis bases (ketones and carbazoles).
-------
Recovery of Bitumen
Various methods have been employed to recover bitumen from tar sands. One
approach utilizes extraction techniques to recover bitumen from the mined ore.
These processes either use water, solvent (diluent) or a mixture of water and
solvent. The water is used to separate the bitumen from the ore and as a
flotation media. Several hot-water-solvent recovery systems have been tested
in recent years. For an example, Arizona Fuels Corporation of Salt Lake City,
Utah demonstrated a recovery unit which successfully separated bitumen from
the tar sands ore in an above ground retorting facility.(2) The separation
is effected by pre-conditioning the tar sands ore in a heated diluent. Then,
after the ore decomposes in the hot diluent, it is pumped as a slurry into a
flotation chamber. There it is washed several times with an "aqueous solu-
tion." The diluent/tar mixture is skimmed from the flotation chamber and
conveyed to an oil recovery unit where the sludge and water are removed as
waste byproducts. The diluent/tar mixture is separated via distillation with
the diluent returned to the process and the oil collected for marketing,, (2)
Similar processes have been tested in pilot facilities sponsored by the
State of Utah and/or the University of Utah Research Institute. One of two
samples used in this study came from a pilot facility engaged in experimental
work utilizing hot water solvent extraction techniques. The pilot facility
was operated jointly by the State of Utah and a privately owned company,
Enercor.
It has been recognized that a large percentage of tar sand deposits are
embedded too deeply to be mined economically. Therefore, the oil must be re-
covered in-situ. Most in-situ methods involve means for reducing viscosity as
well as supplying energy for displacement of the bitumen. "For direct combus-
tion techniques, two wells are drilled through the overburden layers into the
tar sands deposit area. Ignition occurs at the air injection well inducing a
combustion front to move through the formation in the direction of air flow
toward the production well. During combustion, part of the bitumen is
""thermally cracked providing fuel for the duration of combustion. Oil and water
vapors are generated as a result of the combustion sequence where they move
forward into the unheated portion of the deposit area called a reservoir.
Here, the vapors cool and condense.(5) The freed bitumen is then pumped to
the surface. Core sections were obtained for this study from a direct combus-
tion in-situ experiment conducted at Asphalt Ridge, Utah, by the IJETC.
Whether the tar sands are retorted and discarded above ground following a
surface or underground extraction process or combusted in-situ, environmental
problems exist which necessitate leachate characterization studies on both
naturally occurring and processed tar sands matrices.
-------
SECTION 2 -
RESEARCH PROTOCOL
Experimental Program
In order to determine the chemical composition of tar sands leachate
approximately twenty-eight feet of three inch tar sands core was obtained from
the TS-2C direct combustion in-situ experiment conducted at Asphalt Ridge by
the LETC. Segments of the core were recognized as being either combusted or
non-combusted. Of the total length of core received by the researchers, only
ten feet was identified as being affected by combustion. The combusted section
contained no visible bitumen content; whereas, the non-combusted section
contained an abundant amount. In addition, a fifty-five gallon drum of pro-
cessed tar sand (spent sand) was obtained from Enercor's above ground retort
pilot plant in Salt Lake City. All together three types of tar sands matri-
ces were to be extracted and analyzed: combusted core (cc), uncombusted core
(uc), and spent sand (ss).
Shake and extraction tests were conducted in an effort to assess the
characteristics of tar sands leachate. The leachate was analyzed by the EPA
analytical support group IERL, Cincinnati, for parameters specified by the
drinking water quality criteria (6) and for-toxic components thought to be--
present in the leachate. In all, twelve different water quality tests plus
trace element analyses were conducted on the leachate samples generated from
the shake and extraction procedures (see Table 4).
Materials & Methods _
Tar Sand Cores - In July of 1981, the Oil Shale and Energy Mining Branch,
IERL, received the three inch diameter core from LETC. There were several
different core lengths. The Army Corps of Engineers, Ohio River Division
Laboratory, was contacted to crush portions of the core. In accordance with
specifications required by the extraction procedures, the material was screen-
ed through a 9.523 mm sieve (3/8" U.S. standard sieve opening). Although the
specifications were met for the combusted portion of the core, the uncombusted
core gummed-up in the mechanical crushers used by the Corps. An alternate
method of crushing the material with a press proved to be more successful.
The spent sand from the above-ground retort operation was kept in a cov-
ered drum to avoid contamination. Samples were taken from the drum as need-
ed. The sand was dark brown in color and imparted a heavy petroleum odor. A
sieve analysis was performed on the spent sand (see Figure 4).
Extraction Procedure (EP) Toxicity Test (7)
The Resource Conservation and Recovery Act's (RCRA) EP Toxicity Test is a
Taboratory test designed to simulate the leaching that a waste will undergo
8
-------
100
S3
LU
CQ
DC
LU
z
LU
u
DC
LU
CL
U.S. STANDARD SIEVE NUMBERS
810 1416'20;30 40 50 70.100140200
1 0.5
GRAIN SIZE IN MILLIMETERS
100
0.1
0.05
FIGURE 4. Sieve Analysis of Spent Tar Sand.
-------
when disposed in a landfill. A representative sample of the waste is extracted
at pH 5 with distilled water and acetic acid. The extract is then analyzed for
various substances. A rotary extractor was used to conduct all extraction
procedures. The methods for leaching the tar sands are outlined below.
1) Extraction of solid material - Two lOOg samples of the spent surface,
processed tar sands, two lOOg samples of the crushed, affected core,
and two lOOg samples of the crushed unaffected core (six samples
total) were weighed and placed in individual cells in an extractor
with sixteen times their weights {1.6 liters) of deionized water.
An acceptable extractor is one which imparts sufficient agitation to
the mixture to not only prevent stratification of the sample and
extraction fluid, but also to insure continuous contact. A six-
bottle rotary extractor obtained from the Associated Design Manu-
facturing Co. was utilized.
The pH was maintained manually with a calibrated pH meter. The
extractor was turned on for one minute, then stopped. The pH was
adjusted to 5.0 + 0.2 with 0.5 N acetic acid and then the extraction
continued for 24~hours. The pH of the solution was adjusted at 15,
30, and 60 minute intervals, moving to the next longer interval if the
pH did not have to be adjusted more than 0.5 pH units. The adjustment
procedure was continued for the first six hours. If at the end of the
24 hour extraction period, the pH of the solution was not below 5.2
and a maximum amount of acid (4 g per gram of solids) had not been
added, the pH was adjusted to 5.0 _+0.2 with the extraction continuing
for an additional four hours. Again the pH was adjusted at one hour
intervals.
2) Separation Procedure - A vacuum filter employing coarse to fine filter
media was used to separate the liquid phase from the solid. The li-
quid was stored at 4°C, unless otherwise specified, for subsequent
analysis.
3) Procedure for Analyzing Extract - Lab analyses consisted of the list
shown in Table 4. The stored liquid from step 2 was segregated into
separate flasks and preserved as required. The individual liquid
samples were prepared for analysis and analyzed within the specified
holding times.
This procedure was run in triplicate and is consistent with the other
extraction methods (see below). A modified EP toxicity test was also
performed on samples without the addition of the acetic acid. The
same separation and analysis procedures were followed.
ASTM (D-3987) Method A-l Modification (8) - The ASTM shake extraction
test is a standard test intended to be used as a rapid means for obtaining an
extract from solid waste. The extract is then examined for the release of
various constituents. This method provided a third set of leachate data,
offering a more complete environmental assessment.
The procedure for this test utilizing the extractor described above fol-
• lows the steps listed below.
10
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TABLE 4. LABORATORY ANALYSES FOR TAR SAND SAMPLES
Measurement
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
PH
Temperature
Chloride
Alkalinity (on
water-only
Bicarbonate,
carbonate
Cyanide, total
Ammonia
Fluoride
Mercury:
Dissolved
Sulfate
Sulfide
Conductivity
Filterable
Carbon
Total Organic
Residue
Total Suspended
Metals*:
Dissolved
EPA
Method
150.1
170.1
Ion
chromatograph**
Titration 310.1
Ion
chromatograph**
Electrode 350.3
Electrode 340.2
AAS - cold vapor
215.1
Ion
chromatograph**
Titration 376.1
120.1
415.1
160.0
AAS
Sample Holding
Volume Time
2 hr.
—
200ml 7 d.
200ml 14 d.
50ml 14 d.
150ml 28 d.
50ml 28 d.
400ml 28 d.
300ml 28 d.
500ml 28 d.
100ml 28 d.
20ml 28 d.
500ml
500ml 6 mo.
Container*** Preservation
P.G
P,G
P,G
P,6
P,G
P,G
P
G
P,G,
P,G
P,G
G
G
P,G
Determine on site
Determine on site
None
4°C
4°c
4°C
pH<2 (H2S04)
None
Filter
... pH< (HN03)
4°C
4°C
Zinc Acetate
4°C
pH< (H2S04)
None
pH< (HN03)
*Metals: Al, As, Ba, Ca, Fe, Ni, K, Na, Zn.
**Not an EPA method.
***p = plastic, g = glass
11
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1) Place 70 grams of sample in the leach container, then add 1400 ml of
the test water.
2) Close the container and shake to uniformly mix the contents.
3) Place the container on the extractor so that the top of the container
is four (4) inches above the holder and the bottom of the container is
four (4) inches below the holder (center mounted). Use the remaining
100 ml of water to wash down the sides of the container.
4) Turn on the extractor and agitate the sample for 18 hours.
5) Separation and analysis procedures - follow same procedure used for
RCRA EP toxicity tests.
Chemical Analysis
During the course of the six week study, the three tar sands matrices were
extracted by using EP toxicity (with and without acidification) and ASTM tests.
Three runs were conducted successively. All sample sets were analyzed by the
Analytical Support Group, Program Operations Office, lERL-Ci. The laboratory
used EPA approved methods (10) and Standard Methods, 15th ed., (11) when per-
forming leachate (extract) analysis^Tracemetal (inorganics) analysis was
accomplished with a Perkin-Elmer 4000 atomic absorption spectrophotometer with
an accessory HGA 400 graphite furnace when necessary (e.g., arsenic).
PrecTsion and Accuracy (QA7QC)
Quality control procedures were used for the determination of various
constituents so that the precision and accuracy of the analytical techniques
could be properly documented. Accuracy of the data generated during this study
was evaluated by calculating recovery efficiency for samples spiked ln_the
laboratory with known concentrations of analytes. This was determined by
computing the percent recovery (%R) of a known sample concentration spiked with
a prepared standard. These standards were either prepared in the analytical
laboratory performing the analysis or obtained from the Environmental Monitor-
ing Support Laboratory (EMSL), EPA. Percent recoveries were computed by
dividing the amount recovered by the amount added. An aliquot of 1 ml sample
included a QA spike for recovery determinations. Percent recovery is a
measure of accuracy where recoveries of 100 +_ 10% are deemed acceptable with
100+5% being optimum. Analysis of total suspended solids (TSS) offers the
only exception to this rule. Percent recoveries in the range of 100 j- 20%
are acceptable when considering the hygroscopic nature of TSS. QA spikes are
indicated in the data tables respective to those sample sets spiked for
recoveries.
Quality control (QC) samples were also utilized with the accuracy of
testing procedures being based upon the difference between measured values
and actual values. These QC values are also reported as percent recovery
I%R). The QC standards were either prepared from Standard Methods in the lab
, or obtained from EMSL. QC values are presented in the data tables respective
to the set of samples with which they were to be analyzed.
12
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SECTION 3
RESULTS
The data for total suspended solids, total organic carbon and alkalinity
are also presented in graphic form in Figures 5, 6, 7, and 8, respectively.
The data generated from the extract analyses are presented in Tables 5 through
13. When QA and QC results were obtained, they were presented in association
with the sample set to which they correspond. Each data block represents
results pertaining to a particular extraction method. Some analyses were not
performed on the samples from the ASTM extraction procedure, since results from
the EP toxicity tests indicated that the analyte concentrations would be too
close to the detection limit to provide meaningful data. Therefore, there are
no ASTM results for chlorides, fluorides, sulfides and cyanide.
The results of the pH adjustments for EP toxicity procedures utilizing the
acid adjustment indicated that the combusted and uncombusted cores were on
the basic side of the pH spectrum. All of the allotted amount of acetic acid
(40 ml) was added to the samples to keep the pH under 5 +_ 0.2. In most instances
the full complement of acid was also administered to adjust pH for the spent sand
samples.
Blanks were run for most of the determinations and their associative values
are presented below their respective data blocks. These blanks were derived
from the "clean" sand that was extracted simulatenously and similarly for each of
the three extraction procedures. With the exception of total organic carbon
(TOC) all other determinations focused on inorganic chemical parameters.
13
-------
100,000'
10,000
1000
100
10
Over 1OO.OOO
Key
t-%3 Spent Sand
Uncombusted
Combusted
n Blank
CO
2
"o
0)
•o
0)
•a
c
0)
a
CO
3
CO-
1ft
3
CD
•o
'5
<
o
z
RCRA
With Acid
RCRA
No Acid
ASTM
-------
1000
TJ
°o
100
10
RCRA
With Acid
Key
Spent Sand
Uncombusted
Combusted
f""l Blank
n
RCRA
No Acid
ASTM
FIGURE 6, Total Organic Carbon.
15
-------
1000
Key
FxJ Spent Sand
Uncombusted
BillII Combusted
I | Blank
100
o>
I0_-
•
•-
n
RCRA
With Acid
ASTM
No
FIGURE 7. Sulfate.
16
-------
1000
100
OJ
10
Key
t-Xl Spent Sand
Uncombusted
Combusted
Blank
RCRA
With Acid
RCRA
No Acid
ASTM
FIGURE 8. Alkalinity as CaCO3.
17
-------
Summary of Analytical Results
TABLE 5. SULFATES (EPA METHOD #375.4, ION-CHROMATOGRAPH)
EP Toxicity
Run
No.
1
2
3
Run
No.
1
2
3
SS
mg/1
114
53.4
109
Blank =
EP
SS
mg/1
101
124
119
Blank =
Tar Sands
QA UC
%R mg/1
99 228
47.5
41
0.89 mg/1
With Acid
Matrix
QA
%R
CC
mg/1
105
13.2
18
QA
%R
98
100
Toxicity Without Acid
Tar Sands
QA UC
%R mg/1
90 47
59
99 45
1.39 mg/1
Matrix
QA
%R
86
CC
mg/1
38
50
30
QA
%R
84
99
ASTM
Run
— No.
1
2
3
SS
• • mg/1
74
112
92
Tar Sands
QA UC
•%R. mg/T
104 34
97 57
100
Matrix
QA
- %R-
114
97
CC
mg/1 •
31
33
QA
%R
114
103
Fifteen out of 25 samples were spiked to monitor recovery efficiency (QA)
with recoveries ranging from 84 to 114%. The average recovery was 92%.
18
-------
TABLE 6. CHLORIDES (EPA METHOD #325.3 WITH ELECTRODE)
Run
No.
1
2
3
SS
mg/1
1.5
1.3
1.4
Blank
EP Toxicity With Aci
Tar Sands Matrix
QA UC QA
%R mg/1 %R
1.6 107
1.1 104
101 1.05 97
= 0.99 mg/1
d
CC
mg/1
1.6
1.3
1.2
QA
%R
98
EP Toxicity Without Acid
Run
No.
1
2
3
$S
mg/1
0.9
1.18
1.11
Tar Sands Matrix
QA UC QA
%R mg/1 %R
124 0.57 103
97 0.73 104
101 0.74
CC
mg/1
1.56
1.9
0.8
QA
%R
89
80
101
Blank = 0.47 mg/1
All values are averages of duplicate analytical determinations with the
exception of QA recovery efficiencies.
19
-------
TABLE 7. FLUORIDES (EPA METHOD #340.2)
EP Toxicity With Acid
Run
No.
1
2
3
Run
No.
1
2
3
S5
mg/1
0.4
0.12
0.15
Blank =
EP
SS
mg/1
.24
.18
.2
Tar Sands Matrix
QA UC QA
%R mg/1 %R
1.4
<0.1
<0.1
0.0 mg/1
Toxicity Without Aci
Tar Sands Matrix
QA UC QA
%R mg/1 %R
115 .16
88 .16 100
.15
CC
mg/1
<0.1
0.1
0.1
d
CC
mg/1
1.3
1.09
1.27
QA
%R
QA
%R
Blank = 0.0 mg/1
Duplicates were run on all samples and the results were averaged. Three
QA samples were performed with recovery efficiencies- ranging from 88 to 115%.
TABLE 8. SULFIDES (EPA METHOD #376.1 - TITRATION)
EP Toxicity With Acid
Tar Sands Matrix
Run - SS - QR - DC - QK CC
No. mg/1 %R mg/1 %R mg/1 %R
1
2
3
-
.3
.3
-
.4
.3
-
.4
.6
EP Toxicity Without Acid
Tar Sands Matrix
Run SS QA UC QA CC QA
No. mg/1 %R mg/1 %R mg/1 %R
1
2
3
.9
.2
.4
<.l
.2
.2
.6
.8
1.0
The values recorded for the sulfide determination were too close to the
detection limit to warrant QA spikes.
^
20
-------
TABLE 9. ALKALINITY AS CaC03 (EPA METHOD #310.1 - TITRATION)
EP Toxicity With Acid
Tar Sands Matrix
Run
No.
1
2
3
Run
No.
1
2
3
Run
No.
1
2
3
SS QA UC QA CC QA
mg/1 %R mg/1 %R mg/1 %R
17 8.1 115.5
507 0 446 86*
577 0 510
*EMSL Standard Addition
Blank = 0 mg/1
EP Toxicity Without Acid
Tar Sands Matrix
SS QA UC QA CC QA
mg/1 %R mg/1 %R mg/1 %R
39.1 9.7 60.0
47.2 7.7 76.6
42.2 99.5 7.2 97.6 60.0 95
Blank = 8.1 mg/1
ASTM
Tar Sands Matrix
SS QA UC QA CC QA
mg/1 %R mg/1 %R mg/1 %R
31.0 12.4 55.1
35.2 6.2 51.1
25.3
Two QC primary standards were prepared by EMSL for analysis. The results are
as follows:
QC Sample
WP 478
WP 478 (2.
Reported Value True Value %R
22.56 mg/1 21.7 mg/1 104%
25) 53.82 mg/1 54.3 mg/1 99%
21
-------
TABLE 10. CONDUCTIVITY (EPA METHOD #120.1 - WHEATSTONE BRIDGE)
EP Toxicity With Acid
Run
No.
1
2
3
Run
No.
1
2
3
Run
No.
1
2
3
SS
umhos/cm
1300
1500
1300
EP
SS
umhos/cm
270
330
280
SS
umhps/cm
220
280
220
Tar Sands Matrix
uc cc
umhos/cm umhos/cm
1000 1000
300 1000
1300 400
Toxicity Without Acid
Tar Sands Matrix
UC CC
umhos/cm umhos/cm
130 160
150 190
130 180
ASTM
Tar Sands Matrix
UC CC
umhos/cm umhos/cm
120 170
150 100
-
QC
%R
99
99*
99
QC
%R
96.2
99
99
QC
%R
93
94
99
*A 0.01m KCL standard was prepared in the laboratory in accordance to Standard
Methods and evaluated for recovery efficiency (% R). Specific conductance
measurements are used in water analysis to obtain a rapid estimate of the
dissolved solids content of a sample. Significantly higher values (umhos/cm)
were recorded for the EP toxicity procedure using acid adjustment.
22
-------
TABLE 11. TOTAL SUSPENDED SOLIDS (EPA METHOD #160.0)
Run
No.
1
2
3
Run
No.
1
2
3
Run
No.
1
2
3
EP Toxicity With Aci
Tar Sands Matrix
SS
mg/1
1,340
810
264
Blank =
EP
SS
mg/1
6,640
4,220
1,968
Blank =
SS
mg/1
7,420
5, '094
6,995
QA UC QA
%R mg/1 %R
320
348
28
63 mg/1 QA 133%R
d
CC
mg/1
638
446
205,150
QA
%R
Toxicity Without Acid
Tar Sands Matrix
QA UC QA
%R mg/1 %R
626 83
4,596
2,894 89
26 mg/1 QA 127%R
ASTM
Tar Sands Matrix
QA UC QA
%R mg/1 %R
19,332
37 3,720
94
CC
mg/1
31,632
7,456
17,216
CC
mg/1
63,932
"15,500
-
QA
%R
104
QA
%R
The QA spike for TSS determination came from EMSL and was prepared from a
primary standard.
23
-------
TABLE 12. TOTAL ORGANIC CARBON ANALYSIS (EPA METHOD #415.1)
Run
No.
1
2
3
Run
No.
1
2
3
Run
No.
1
2
3
EP
SS
mg/1
299
332
335
Blank =
EP
55
mg/1
15
13
15
Blank =
SS
mg/1
14
13
14
Toxicity With Acid
Tar Sands Matrix
QA UC QA CC QA QC
%R mg/1 %R mg/1 %R %R
270 230 98
309 299 97
103 347 106 320 105 101
1.1 mg/1
Toxicity Without Acid
Tar Sands Matrix
UC CC QC
mg/1 mg/1 %R
8 5 99
9 9 98
6 12
0.91 mg/1
ASTM
Tar Sands Matrix
UC CC QC
mg/1 mg/1 %R
6 12 98
' ' 6 12 •-•--
QC samples were obtained from EMSL with recovery efficiencies ranging
from 97 to 101%. Very little TOC was present in the unacidified extraction
methods.
The extracts were analyzed for cyanide by an electrode method (not an
approved EPA method). However, results were recorded below the detection
limit (<0.05 mg/1) for both EP toxicity procedures.
Trace Metal Analysis (AAS)
The following table shows the averages of the trace metal concentration
measurements for the three runs conducted. The combusted core showed signif-
icantly higher concentrations of trace metals. Calcium, magnesium, potassium,
and sodium were present in the highest concentrations. Arsenic, barium,
'mercury, nickel and zinc were below the detection limit.
24
-------
TABLE 13. TRACE METAL ANALYSIS (mg/1)
EP Toxicity with Acid
CC UC SS
Al .1
Ca 176
Fe .5
Mg 61.6
K 9.0
Na 5.6
ZN .04
Da
Hfl* _ --
ng
Mi
AC
2.3
32
3.0
3.4
1.4
2.9
.32
.3
378
.83
12.9
1.9
2.3
.08
EP Toxicity no Acid
CC UC SS
8.3
78
7
31.4
9.4
6.4
.22
fil 1
an
an
an
.16 2.4
17 65
.5 1.5
2.7 5.0
1.3 1.7
3.8 3.2
.03 .03
locc than O9 _— _
CC
19.9
36
2.9
13.5
8.7
9.2
7.3
ASTM
UC
.15
18
.6
2.9
1.6
1.5
.04
SS
.23
47.6
.57
2.5
4.0
2.1
.18
QC
%R
109
102
100
98
105
104
100
98
100
- 108
*A11 tar sand samples were analyzed in duplicate for mercury (Hg) and seven of them
were spiked with 1 ppb Hg. Recoveries could not be computed for the spikes because the
concentration of the unspiked samples were above the blank but too low for meaningful
detection.
25
-------
SECTION 4
DISCUSSION
Based on the conventional water quality determinations examined during
this study, both shake and extraction procedures provided some insight into
the fate of various contaminants that may be prevalent in the leaching of tar
sands residue and processed waste. Since the primary objective in this study
was to charactize the constituents present in the leachate, no attempt was made
to model contaminant migration into groundwater reservoirs and streams.
A preliminary comparison can be made among the various extraction methods
especially with respect to the acid addition step present in the RCRA EP tox-
icity test. When the EP toxicity test was run with the acetic acid adjust-
ment, more often than not, higher concentrations were recorded. This is to
be expected since many trace metals will tend to be more Teachable under
acidic conditions. However, it is important to evaluate the same parameters
for neutral and/or basic conditions, since this type of information may more
closely represent field disposal conditions. Unless otherwise stated, most
of the discussion will revolve around results obtained from the RCRA EP
toxicity procedure (using acid) since it is the most sensitive of the three
methods performed.
In examining the data for hazardous waste contaminants, only three
(arsenic, barium, and mercury) are listed in the Federal Drinking Water Quality
Standards.(11) These values are only provided as a reference point; rather
than to imply this discharge should meet drinking water standards. Those
contaminants included in the standards which were .measured in this study are
presented in Table 14 below.
TABLE 14. WATER QUALITY STANDARDS* (11)
EPA
Hazardous
Waste
Number
D004
D005
D009
Contaminant
Arsenic
Barium
Mercury
Maximum
Concentration
(mg/1 )
.05
1.0
.002
Measured
Concentration
(mg/1 )
< .02
<1.0
< .001
*Established by the National Interim Primary Drinking Water Regulations.
Upon examination of the results, it is apparent that none of the hazardous
constituents listed in Table 14 are in excess of the maximum allowable concen-
trations.
26
-------
Another approach to examining the potential for groundwater contamination
is to compare the results of the extraction tests to water quality criteria
which have been summarized by the Environmental Criteria and Assessment Office
(ECAO), EPA.(6) Of particular interest are the priority pollutants prevalent
in the sample extractions. The following table lists some values established
by that office for those contaminants found in the tar sands leachate.
TABLE 15. WATER QUALITY CRITERIA FOR PRIORITY POLLUTANTSa (12)
Average Daily Intakes'3
Criteria Uncertainty
Priority Pollutant ADI (mg/1) Factor
As
*
Hg
Ni
Zn
Cyanide
.01
.75
7.5
3.8
10
1,000
10
100
^Federal Register 45:79347, 1980
bAverage Daily Intakes (ADI) are based upon the water consumption of
2 L/day tainted by the presence of the pollutant
Upon reviewing Tables 13 and 15, it is apparent that, with concentra-
tions of cyanide less than the detectable limit of .05 mg/1, very little
opportunity exists for cyanide to be a problematic constituent in tar sands
leachates. The other listed priority pollutants, zinc, mercury and nickel
are present in very low concentrations. All the other trace metals not
listed as priority pollutants yielded relatively low concentrations for tar
sands leachate.
With respect to other parameters analyzed in this study, only TOC and
su'lfate determinations exhibited concentrations high enough to cause any con-
cern. Whether this level of concentration can be expected from the addition of
acid for pH adjustment during the extraction procedure or whether organic
constituents are released, is a matter that deserved more consideration. A
more thorough characterization in the future may be necessary to look at spe-
cific organic analyses; especially, phenols and compounds associated with the
various functional groups prevalent in tar sands bitumen.
27
-------
SECTION 5
CONCLUSIONS
The initial laboratory tests conducted under this study indicate that
leachates from spent tar sands may not contain significant amounts of toxic
pollutants but may contain substantial amounts of sulfate and total organic
carbon [TOO. Only five constituents of the specific parameters analyzed were
identified as priority pollutants (e.g., those elements posing the greatest
risk to health and the environment). Of the five priority pollutants tested
(cyanide, mercury, nickel, arsenic and zinc), all exhibited low concentra-
tions. However, concentrations of sulfate and TOC were fairly high and could
impact surface and/or groundwater quality. Those trace elements which were
present to any significant degree were not considered to be highly toxic or
deleterious to the environment.
It is recommended that further work be undertaken to characterize specif-
ic organics, such as, hydrocarbon combustion products and phenols. It has
been recommended that digestion tests be performed on the spent filter paper
from the shake and extraction tests. Future work may involve some ground-
water modeling of the more problematic constituents characterized by this
study.
28
-------
REFERENCES
1. Oblad, A.6., et al., "Recovery of Bitumen from Oil-Impregnated Sandstone
Deposits of Utah." In Oil Shale and Tar Sands, ed. John Smith and Mark
Atwood, NY, NY: American Institute of Chemical Engineers, 155, 72 (1976):
69-78.
2. Lowe, R.M., "The Asphalt Ridge Tar Sand Deposits," In Oil Shale and Tar
Sands, ed. John Smith and Mark Atwood, NY, NY: American Institute of Chemical
Engineers, 155, 72 (1976): 55-60.
3. Campbell, J.A. and Ritzma, H.R., "Geology and Petroleum Resources of the
Major Oil-Impregnated Sandstone Deposits of Utah." In The 10CC Monograph
Series; Tar Sands, ed. Douglas Ball, et al., Interstate Oil Compact
Commission, Oklahoma City, Oklahoma, (1982): 27-43.
4. Kuuskraa, V.A. and Doscher, T.M., "The Economic Potential of Domestic Tar
Sands." In The lOCC Monograph Series: Tar Sands, Ed. Douglas Ball, et
al., Interstate Oil Compact Commission, Oklahoma City, Oklahoma, (1982):
185.
5. Cupps, C.Q., at al., "Field Experiment of In-situ Oil Recovery from a Utah
Tar Sand by Reverse Combustion." In Oil Shale and Tar Sands, ed. John
Smith and Mark Atwood, NY, NY: American Institute of Chemical Engineers,
155, 72, (1976): 62, 63.
6. U.S. EPA, "Summary of Published Acceptable Daily Intakes (ADIS) for EPA's
Priority Pollutants." Environmental Criteria and Assessment Office, U.S.
EPA, Cincinnati, Ohio, (1983).
7. U.S. EPA, "Test Methods for Evaluating Solid Waste: Physical/Chemical
Methods." (SW-846B), U.S. EPA, Washington, DC, (1981).
8. ASTM, "Standard Test Method for Shake Extraction of Solid Waste with Water."
(D-3987), In Annual Book of ASTM Standards, ASTM, Philadelphia,
Pennsylvania, (1981): 2652.
9. U.S. EPA, "Methods for Chemical Analysis of Water and Wastes." EPA-600/4-79-
020, U.S. EPA, Cincinnati, Ohio, (1979).
10. American Public Health Assoc. Standard Methods for the Examination of Water
and Wastewater. 15 Ed., APHA^ AWWA, AND WPCF, Washington, DC";(1980).
11. 40 CFR Part 141, EPA Water Programs, December 24, 1975 (Vol. 40, No. 248).
12. Federal Register, 45:79347, (1980)«
29
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PROJECT SUMMARY
TAR SANDS LEACHATE STUDY
by
Douglas W. Grosse
Environmental Engineer
and
Linda McGowan
Physical Scientist
U.S. Environmental Protection Agency
Industrial Environmental Research Laboratory
Cincinnati, Ohio 45268
-------
This project summary describes the research initiated at the EPA's Test
and Evaluation (T&E) Facility, to assess the potential for release of contam-
inants to ground and surface waters from in-situ and above-ground processing of
western tar sands. The purpose of this effort was to provide information that
would (1) assist regulatory offices in permitting the mining and processing
operations, (2) establish a data base for developing and reviewing monitoring
plans and (3) support efforts to establish guidelines for ultimate disposal of
solid wastes generated from tar sands operations. Such information will assist
the development of an environmentally acceptable tar sands industry.
Preliminary studies on assessing the environmental implication of in-situ
extraction, as well as above-ground retorting, are scarce. There is heightened
concern in states such as Utah regarding the environmental impact on local
water supplies from tar sands mining and in-situ recovery operations.
An in-house research project was conducted by the EPA's Industrial
Environmental Research Laboratory (IERL) at the T&E Facility in Cincinnati,
Ohio, to provide information concerning the potential for release of contam-
inants to groundwater from in-situ and above-ground processed tar sands. This
study examined the composition of the leachate that may be generated from raw
tar sand cores and spent tar sand waste.
This project summary was developed by EPA's Industrial Environmental
Research Laboratory, Cincinnati, Ohio, to announce key findings of the research
project which is fully documented in a separate report of the same title (see
Project Report ordering information at back).
Experiment
In determining the chemical composition of tar sands leachate approximately
28' of three inch tar sand core was obtained from the TS-2C forward combustion
in-situ experiment .conducted at Asphalt Ridge by the Laramie Environmental
Technology Center (LETC). Segments of the core were recognized as being either
combusted or non-combusted. In addition, a fifty-five gallon drum of processed
tar sands (spent sand) was obtained from an above-ground retort pilot plant in
Salt Lake City. In all, three types of tar sands matrices were extracted and
analyzed: combusted core (cc), uncombusted core (uc) and spent sand (ss).
Shake and extraction tests were conducted in an effort to assess the
characteristics of tar sands leachate. The leachate was analyzed by the EPA
analytical support group, IERL, Cincinnati, for parameters specified by the
drinking water quality standards and criteria. Screening for toxic components
thought to be present in the leachate was also performed. The Resource
Conservation and Recovery Act's (RCRA) EP Toxicity Test (with and without acid
addition) was used to simulate tar sands leachate generation. The ASTM shake
extraction procedure was also performed on all tar sand matrices to generate a
third set of data for evaluation.
Results
In all, twelve different water quality tests plus trace metal analyses
were conducted on the leachate samples generated from the shake and extraction
procedures.
-------
The following table shows the averages of the trace metal concentration
measurements for the three runs conducted. The combusted core showed signifi-
cantly higher concentrations of trace metals. Calcium, magnesium, potassium,
and sodium were present in the highest concentrations. Arsenic, barium,
mercury, nickel and zinc were below the detection limit.
TABLE 1. TRACE METAL ANALYSIS (mg/1)
EP Toxicity with Acid
CC UC SS
Al .1 2.3 .3
Ca 176 32 378
Fe .5 3.0 .83
Mg 61.6 3.4 12.9
K 9.0 1.4 1.9
Na 5.6 2.9 2.3
ZN .04 .32 .08
Ba
Un*
ny
Mi
AS
EP Toxicity no Acid
CC UC SS
8.3
78
7
31.4
9.4
6.4
.22
All
All
All
All
.16 2.4
17 65
.5
2.7
1.3
3.8
.03
less
less
less
less
1.5
5.0
1.7
3.2
.03
than 1 0
than .001 -
than .2 -
than O?
ASTM QC
CC UC SS %R
19.9 .15 .23 109
36 18 47.6 102
2.9 .6 .57 100
13.5 2.9 2.5 98
8.7 1.6 4.0 105
9.2 1.5 2.1 104
7.3 .04 .18 100
QO
1 nn
i r\Q
*A11 tar sand samples were analyzed in duplicate for mercury (Hg) and seven of
them were spiked with 1 ppb Hg. Recoveries could not be computed for the
spikes because the concentration of the unspiked samples were above the blank
but too low for meaningful detection.
In examining the data for hazardous waste contaminants, only three (ar-
senic, barium and mercury) are listed in the Federal Drinking Water Quality
Standards. These values are provided as a reference point rather than to imply
that discharge should meet drinking water standards. Those contaminants in-
cluded in the standards which were measured in this study are presented below.
. TABLE 2. WATER QUALITY STANDARDS*
EPA
Hazardous
Waste
Number
D004
D005
D009
Contaminant
Arsenic
Barium
Mercury
Maximum
Concentration
(mg/1 )
.05
1.0
.002
Measured
Concentration
(mg/1 )
< .02
<1.0
< .001
^Established by the National Interim Primary Drinking Water
Regulations.
-------
Upon examination of the results it is apparent that none of the hazardous
constituents listed above are in excess of the maximum allowable concentrations.
With respect to other parameters analyzed in this study, only TOC and
sulfate determinations exhibited concentrations high enough to cause any con-
cern. Whether this level of concentration can be expected from the addition
of acid for pH adjustment during the extraction procedure or whether organic
constituents are released, is a matter that deserves more consideration. A
more thorough characterization in the future may be necessary to look at speci-
fic organic analyses, especially, phenols and compounds associated with the
various functional groups prevalent in tar sands bitumen.
Conclusions
The initial laboratory tests conducted under this study indicate that
leachates from spent tar sands may not contain significant amounts of toxic
pollutants but may contain substantial amounts of sulfate and total organic
carbon (TOC). Of the five priority pollutants tested (cyanide, mercury, nickel,
arsenic and zinc), all exhibited low concentrations. However, concentrations
of sulfate and TOC were sufficiently high to impact surface and ground-
water quality.
Recommendati ons
It is recommended that further work be undertaken to characterize specific
organics, such as, hydrocarbon combustion products and phenols. It has been
recommended that digestion tests be performed on the spent filter paper from
the shake and extraction tests. Further work may involve some groundwater
modeling of the more problematic constituents characterized by this study.
------- |