United States
Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory
Las Vegas NV 89114
Research and Development
EPA-600/S4-83-055 June 1
Project Summary
Groundwater Monitoring
Recommendations for Oil
Shale Development
L. G. Everett
EPA has completed a five-year pro-
ject to develop groundwater quality
monitoring recommendation* for west-
ern oil shale development. Five major
reports have been published. The com-
pendium reports consider the various
production processes (mining, retort-
ing, and oil upgrading) and key environ-
mental factors (organic and inorganic
characterization, environmental con-
trol, and limitations) related to oil shale
development. Each of the potential
sources of pollution and specific pollu-
tants associated with each source have
been identified.
Based upon the EPA monitoring meth-
odology, a preliminary groundwater
monitoring program for Utah oil shale
tracts U-a and U-b, and a monitoring
strategy for modified in situ oil shale
retorting was developed. Using federal
lease tracts C-a and C-b in Colorado, an
exhaustive review of strategies and moni-
toring recommendations for modified in
situ (MIS) oil shale retorting has been
conducted, and groundwater monitoring
recommendations have been developed
for geophysical logs and hydraulic testing
methods. Sampling protocols covering
well design, sampling costs, sample
col lection proced u res, a nd sa mple preser-
vation and handling have been developed.
This Project Summary was developed
by EPA's Environmental Monitoring
Systems Laboratory, Las Vegas, NV, to
announce key findings of the research
project that is fully documented in five
separate reports (see Project Report
ordering information at back).
Introduction
EPA is completing a five-year project to
develop groundwater quality monitoring
recommendations for Western U.S. Oil
Shale Development (Figure 1). Four re-
ports have been published previously by
EPA. Another report, which is emphasized
in this summary, has been published at
this time. All five reports are described in
this project summary so that the reader
can be aware of the relationship of the
reports to each other.
Previously Published Reports
Compendium Reports on
Oil Shale Technology
(EPA-600/7-79-039)
Currently, petroleum companies are
becoming more optimistic about the
commercial prospects of the 95.4 billion
m3 (600 billion bbl) of syncrude locked in
the Green River Formation of the tristate
area of Colorado, Utah, and Wyoming.
This optimism is based on technological
and economic factors that may give shale
oil a good chance to compete with con-
ventional crude oil. The compendium
reports consider the various production
processes (mining, retorting, and oil
upgrading) and key environmental factors
(organic and inorganic characterization,
environmental control, and limitations)
related to oil shale development. This
state-of-the-art survey supports a study
designing groundwater quality monitor-
ing programs for oil shale operations
such as that proposed for Federal Oil
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Idaho I
tOil Shale Formations,
Figure 1. Locations of Federal oil shale
tracts U-a, U-b and C-a, C-b.
Shale Lease Tracts U-a and U-b and C-a,
C-b. Hence, the reports emphasize tech-
nologies applicable to this development
while also providing a general overview
of oil shale technology.
Groundwater Quality
Monitoring of Western Oil
Shale Development:
Identification and Priority
Ranking of Potential
Pollution Sources
(EPA -600/7-79-023)
This document reports the field survey
and literature research performed during
the first phase of the design process. The
goal of this phase is to identify and rank
the major sources of groundwater quality
degradation. The site for which the moni-
toring system is being designed is the
Federal prototype lease tracts U-a and U-b
in eastern Utah. The oil shale operation
proposed for this site includes room-and-
pillar mining, surface retorting by the
Paraho and TOSCO II process, and surface
disposal of spent oil shale.
The priority ranking is based on a
sequence of data compilation and evalua-
tion steps. These steps include identifica-
tion of potential pollution sources, meth-
ods of waste disposal, and potential
pollutants associated with the various
waste sources, and an assessment of the
potential for infiltration and subsequent
mobility of these pollutants in the sub-
surface. The three basic criteria used to
develop the source-pollutant ranking are:
• Mass of waste, persistence, toxicity,
and concentration
• Potential mobility
• Known or anticipated harm to water
use
From the rankings developed for each
of these three criteria, a preliminary
priority ranking of potential pollution
sources and causes and potential pollu-
tants was developed. The highest priority
potential pollutant sources were associ-
ated with the spent shale disposal area:
spent shale; high TDS wastewater, sour
water, and retort water used to moisten
the spent shale; and spent catalysts
deposited in the disposal area. Associated
with these sources are numerous chem-
ical constituents of which total dissolved
salts, selected microinorganics (sodium,
sulfate, and chloride), selected trace
elements (arsenic, fluoride, selenium, and
molybdenum), and organics (polycyclic
aromatic hydrocarbons and carboxylic
acids) are considered the most significant
potential pollutants. In the process area,
the proposed effluent holding pond that
drains the process area watershed, raw
shale storage, and the tankage area were
ranked. Dissolved salts, organics, selen-
ium, arsenic, and tankage contents (fuel,
oil additives, and ammonia) were evalu-
ated.
Groundwater Quality
Monitoring of Western Oil Shale
Development: Monitoring
Program Development
(EPA-600/7-80-089)
This report presents the development
of a preliminary design of a groundwater
quality monitoring program for oil shale
operations, such as proposed for Federal
Prototype Lease Tracts U-a and U-b in
eastern Utah. The methodology used
begins with a priority ranking of potential
pollutant sources and includes assess-
ments of existing or proposed monitoring
programs, identification of alternative
monitoring approaches, and the selection
of recommended monitoring programs
(Figure 2).
A preliminary decision framework for
monitoring design for this type of oil shale
operation is presented. Included under
the broad topic of the monitoring plan are
recommendations for developing back-
ground data bases on pollutant source
characteristics, the hydrogeologic frame-
work of the study area, existing water
quality, and infiltration, as well as recom-
mendations for monitoring pollutant mo-
bility. Hence, needs for baseline charac-
terization are identified and evaluated in
addition to direct operational monitoring
needs. A field and laboratory testing
program based on these preliminary
design recommendations will lead to
development of a final monitoring design
strategy.
Monitoring Groundwater
Quality: The Impact of In Situ Oil
Shale Retorting
(EPA-60O/7-80-132)
This report presents the initial phase of
a research program that will develop a
planning methodology for the design and
implementation of cost-effective ground-
water quality monitoring programs for
modified in situ (MIS) oil shale retorting.
This initial phase includes (1) a review of
MIS development with regard to potential
impacts and a review of current MIS
monitoring programs, and (2) identifica-
tion of key issues, uncertainties, and
unknowns with regard to design and
implementation of monitoring programs.
General Monitoring Strategy
The basic goals are to (1) detect and
measure groundwater flow within the
abandoned retort interval, and (2) detect
changes in groundwater quality from
waste residuals (e.g., spent shale, retort
water) within the abandoned retort zone.
General monitoring strategy recom-
mendations are as follows:
1. Source-specific orientation. Ground-
water quality monitoring networks
should be designed specifically for
detecting groundwater inflow to the
abandoned retort zone and related
effects on groundwater quality. For
the most part, existing hydrogeologic
characterization and baseline moni-
toring programs have a regional-
scale focus.
2. Routine monitoring of selected "indi-
cator" constituents. This is consid-
ered more cost-effective than the
extensive water quality analysis pro-
grams currently implemented. Exten-
sive inorganic and organic analyses
a re i ndicated as a response to i mpacts
detected by such routine.monitoring
but are not needed as part of the
routine monitoring program.
3. Relatively small spatial scale. Moni-
toring well networks should be withir
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Gamma log
Spinner log
Radioactive tracer
log
Density log
Electric log
Seisviewer log
Alluvium
Uinta Formation
x.
"™. -v-i
* Fracture
Figure 2. Proposed monitoring in the spent-shale pile, Uinta Formation
and directly adjacent to abandoned
retort fields.
Interactive design process. The moni-
toring design process is initiated with
site exploration and resource evalua-
tion activities. Hydrogeologic data will
continue to be collected during the
mine and retort construction phases.
These data, in addition to MIS design
changes, may require revision of
groundwater quality monitoring de-
signs. Wells used for baseline studies
provide for initial hydrogeologic char-
acterization but may not be adequate
for operational monitoring needs.
This is particularly true where base-
line programs have a regional-scale
orientation. An iterative (planning-
implementation-reevaluation) pro-
cedure to address monitoring needs
is recommended.
Recently Published Report
Groundwater Quality Monitoring
Recommendations for In Situ Oil
Shale Development
(EPA -600/4-83-045)
This report includes the design to
characterize the hydrogeology of an oil
shale tract, a proper suite of geophysical
logs, proper aquifer testing methods, and
recommendations to aid developers of
commercial oil shale tracts.
Geophysical Methods
The following logs were evaluated to
determine their overall effectiveness in
providing pertinent and reliable hydraulic
data:
Temperature Log
Caliper log
Velocity log
Sonic (acoustic) fog
The following log suite is recom-
mended: temperature, caliper, sonic, and
electric logs. Of more limited value and
receiving secondary or lower priority
ranking are gamma, velocity, density, and
spinner logs. The radioactive tracer and
seisviewer logs are not recommended for
obtaining hydraulic data for oil shale
development.
Hydraulic Methods
Four general methods of hydraulic
testing procedures have been evaluated
and are classed as follows:
Drill stem tests
Dual-packer tests
Long-term pump tests
Single-packer tests.
Review of the testing procedures, equip-
ment costs, and utility of the resulting
data has produced the following priority
ranking:
1. Dual Packer Tests provide specific
hydrologic data at a minimal cost
when multiple tests are conducted in
a single bore-hole. Downhole test
equipment assembly allows for pump-
ing, injection tests, and discrete
water quality sampling.
2. Long-Term Pump Tests produce the
most representative data on bound-
ary conditions and flow patterns.
Sampling Methods
The objective of a groundwater moni-
toring strategy in the oil shale region is to
(1) provide baseline groundwater quality
data, (2) detect and measure groundwater
flow within the abandoned retort interval,
and (3) detect changes induced by waste
residuals (e.g., spent shale, retort water)
within the abandoned retort zone. Com-
pilation of the baseline data and accurate
evaluation of the latter two aspects
requires the collection of representative
groundwater quality samples. However, a
number of factors can influence the
representative nature of the groundwater
samples collected. These factors include
well design, sample collection methods,
and sample handling procedures.
A network of multiple completion wells
is the recommended approach for a
groundwater monitoring program near
the retort fields. Multiple completion well
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design will enable the collection of repre-
sentative data from each of the intervals
potentially affected by the oil shale re-
torting operation. The suggested specifi-
cations for each multiple completion well
are:
• Steel casing and polyvinylchloride
(PVC) well construction material. Al-
though the structural properties of
PVC may preclude its use as a casing
material, the inert characters of PVC
make it ideal as a well construction
material. PVC is also inexpensive
compared with other materials.
• The diameter of the PVC should be
large enough to accommodate a sub-
mersible pump. The recommended
diameter and wall thickness of the
PVC is about 15 centimeters (6 inches)
and schedule 40 (5.5 millimeters of
14/64 inch), respectively.
• Each well of the multiple completion
should be completed in a different
interval; cement grout should be used
to prevent the interconnection of the
different intervals.
• Wells should be developed thoroughly
to remove any traces of drilling fluid or
other materials that may affect water
quality samples.
Sample Collection Procedures:
Sampling of the deep aquifer wells on
Tracts C-a and C-b is accomplished by
bailing and swabbing, respectively. Al-
though these techniques obtain the de-
sired results of collecting a sample, there
is some question as to the representative
nature of the sample collected.
The recommended procedure for bailing
groundwater samples is as follows:
1. Use a flow-through type bailer (e.g.,
Kemmerer sampler). Bailers that are
open at the top and sealed at the
bottom do not have this flow-through
characteristic and will generally be
filled with the first water encountered
in the well (i.e., water near the static
water level).
2. Compile well completion data. Of
particular importance are the well
diameters, casing perforations or
screened interval, depth to aquifer,
aquifer thickness, and total depth.
3. For shallow wells with very slow
groundwater movement, estimate
the well volume from the well com-
pletion data and extract at least one
well volume prior to sample collec-
tion. For both shallow and deep wells
with rapid groundwater movement,
select a sampling point adjacent to
the aquifer.
4. Consistently sample from the same
depth and adjacent to the aquifer
during every sampling effort.
5. Measure temperature, specific con-
ductance, and pH in the field.
If these guidelines are followed, bailing
is a very effective method for collecting
groundwater quality samples.
The following problems are associated
with swabbing:
• There is high potential for introducing
organics into the sample from the oil
field equipment. Care must be taken to
clean the swabbing equipment thor-
oughly.
• The amount of water swabbed from a
well is difficult to determine and can
result in obtaining inconsistent and
non-representative samples. If possi-
ble, the discharge should be carefully
measured to provide the necessary
data for collecting consistent and
representative samples.
• Swabbing may accelerate the plugging
of perforations in the well.
• Swabbing is extremely expensive and
time consuming.
The following procedure is recom-
mended for collecting a representative
sample from a well when using a sub-
mersible pump:
1. Compile well construction data, in-
cluding well diameter, total depth,
and perforated interval, or aquifer
interval in an open well.
2. Measure static water level and esti-
mate well volume.
3. The pump intake should be placed
approximately 1.5 meters (5 feet)
above the open, perforated, or
screened aquifer interval.
4. The discharge rate should be main-
tained at a moderately low rate to
prevent excessive drawdowns in the
aquifer and well and to minimize
turbulent mixing in the annulus.
5. At least one well volume should be
extracted from the well.
6. The parameters most easily moni-
tored in the field are specific conduc-
tance, pH, and temperature. These
parameters should be measured con-
tinuously throughout the pumping
period. Continuously monitoring
these parameters is particularly im-
portant for little-used groundwater
quality monitoring wells.
7. A sample should be collected only
after the field parameters have stabi-
lized for a period of time. It is sug-
gested that a II of the parameters (i.e.,
pH, temperature, and specific con-
ductance) be utilized to determine
representative aquifer water and
prevent premature sample collection
due to the failure of field apparatus.
8. The sample should be collected as
close to the well head as possible to
avoid potential contamination, precip-
itation of solutes, and the loss of
dissolved gases.
Sample Preservation and Handling:
Delayed receipt of the samples at the
analytical laboratory and incorrect pres-
ervation techniques can adversely affect
the sample chemistry greatly. To reduce
potential sample modification, the follow-
ing sample preservation and handling
procedures are recommended:
• Sample volumes, preservatives, and
containers should be selected accord-
ing to the EPA-recommended proce-
dures presented \r\Methods for Chem-
ical Analyses of Waters and Wastes
(U.S. Environmental Protection Agency
Report EPA-600/4-79-020, 1979).
• The samples should be filtered in the
field through a 0.45-micron filter be-
fore preservation.
• Data on past water quality trends
should be consulted to detect an>
anomalies during the sampling effort
• Specific conductance, pH, and tern
perature should be measured in the
field at the time of sample withdrawal
This also applies to reduction-oxidatior
potential and dissolved oxygen deter
minations, if desired.
• Accurate field notes should be main
tained for future data evaluation. Thesi
notes should include: specific time
and dates the activities were per
formed, water levels, source of sample
weather conditions, well completio
data, sample collection method, fiel
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observations, reason for sampling,
field measurements, problems encoun-
tered, and the sample collector's iden-
tity.
• The samples should be shipped each
day from the field to the analytical
laboratory via commercial plane or
bus. Both methods are reliable and
inexpensive, and provide reasonable
assurance against prolonged sample
storage. If the samples cannot be
shipped and received at the laboratory
within 24 hours, on-site analytical
facilities should be provided.
• The chain of custody for the sample
should be as limited as possible to
prevent excessive sample handling,
which can result in shipment and
analysis delays. Individuals should be
designated both in the field and at the
laboratory to ma i nta i n adequate q ua I ity
control with respect to sample hand-
ling and analysis.
If these procedures are followed, sam-
ple handling and preservation techniques
should not affect the analytical results.
This Project Summary was prepared by L G, Everett, who is with Kaman Tempo,
Santa Barbara. CA 94060.
L. G. McMillion is the EPA Project Officer (see below).
This Project Summary covers five different reports entitled:
"Compendium Reports on OH Shale Technology," (Order No. PB 293279/AS;
Cost: $19.00)
"Groundwater Quality Moniitoring of Western Oil Shale Development:
Identification and Priority Ranking of Potential Pollution Sources," (Order No.
PB 300536; Cost: $20.50)
"Groundwater Quality Monitoring of Western Oil Shale Development:
Monitoring Program Development," (Order No. PB 203219; Cost: $ 17.50)
"Monitoring Groundwater Quality: The Impact of In Site Shale Retorting,"
(Order No. PB 177453; Cost: $25.00)
"Groundwater Monitoring Recommendations for In Situ Oil Shale Develop-
ment, " (Order No, PB 84-120 351; Cost: $ 17.50)
The above reports will be available only from: (costs subject to change)
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Monitoring Systems Laboratory
U.S. Environmental Protection Agency
P.O. Box 15027
Las Vegas, NV 89114
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United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
*USGPO: 1984-759-102-1060
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