&EPA
United States
Environmental Protection
Agency
EPA/540/S5-91/009
September 1993
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
Technology Demonstration
Summary
Pilot-Scale Demonstration of a
Slurry-Phase Biological
Reactor for Creosote-
Contaminated Soil
In support of the U.S. Environmental
Protection Agency's (EPA) Superfund
Innovative Technology Evaluation
(SITE) Program, a pilot-scale demon-
stration of slurry-phase bioremediation
was performed May 1991 at the EPA's
Test & Evaluation Facility in Cincinnati,
OH.
In this 12-wk study, a creosote-con-
taminated soil from the Burlington
Northern (BN) Superfund site in
Brainerd, MM, was used to test the
slurry-phase bioreactors. During the
demonstration, five 64-L stainless-steel
bioreactors, equipped with agitation,
aeration, and temperature controls,
were used. The pilot-scale study em-
ployed a 30% slurry, an inoculum of
indigenous polynuclear aromatic hydro-
carbon (PAH) degraders, an inorganic
nitrogen supplement in the form of NH4-
N, and a nutrient broth containing po-
tassium, phosphate, magnesium, cal-
cium, and iron.
During the course of the study, lev-
els of soil-bound and liquid-phase
PAHs, total petroleum hydrocarbons
(TPHs), nutrients, pH, dissolved oxy-
gen (DO), temperature, toxicity, and
microbial populations were monitored.
U.S. Environmental Protection Agency
Region 5, Library (PL-12!)
77 West Jackson BsiloV'-fi. J£th Floor
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The percent reduction of soil-bound
PAHs over 12 wk of testing ranged from
greater than 72% for 4- through 6-ring
PAHs to greater than 98% for 2- and 3-
ring PAHs; the reduction of total PAHs
exceeded 87%.
This Summary was developed by
EPA's Risk Reduction Engineering
Laboratory, Cincinnati, OH, to announce
key findings of the pilot-scale SITE dem-
onstration of slurry-phase biological
treatment that is fully documented in
two separate reports (see ordering in-
formation at back).
Introduction
In response to the Superfund Amend-
ments and Reauthorization Act of 1986
(SARA), the EPA Office of Solid Waste
and Emergency Response and Office of
Research and Development established a
formal program called the SITE Program
to promote the development and use of
innovative technologies to clean up Su-
perfund sites across the country. The pri-
mary purpose of the SITE Program is to
enhance the development and demonstra-
tion of innovative technologies applicable
to Superfund sites so as to establish their
commercial availability.
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-------
The SITE Program comprises four ma-
jor elements:
• Demonstration Program
• Emerging Technologies Program
• Measurement and Monitoring Tech-
nologies Program
• Technology Transfer Program
The objective of the SITE Demonstra-
tion Program is to develop reliable engi-
neering performance and cost data on
selected technologies so that potential us-
ers can evaluate each technology's appli-
cability to a specific site and compare it
with the applicability of other alternatives.
Demonstration data are used to assess
the performance and reliability of the tech-
nology, the potential operating problems,
and approximate capital and operating
costs.
Technologies are selected for the SITE
Demonstration Program through annual
requests for proposals (RFPs). EPA re-
views proposals to determine the tech-
nologies with the most promise for use at
Superfund sites. To qualify for the pro-
gram, a new technology must have been
developed to pilot- or full-scale and must
offer some advantage over existing tech-
nologies. One of the selected technolo-
gies was pilot-scale slurry-phase biologi-
cal treatment, performed by IT Corpora-
tion in conjunction with ECOVA Corpora-
tion, Redmond, WA.
The technology demonstration was con-
ducted at EPA's Test and Evaluation (T&E)
Facility in Cincinnati, OH, during May
through July 1991. In this process, the
soil was suspended in water to obtain a
pumpable slurry, then pumped into a 64-
L, continuously stirred tank reactor (CSTR).
The CSTR was supplemented with air,
nutrients, and an inoculum of microorgan-
isms to enhance the biodegradation pro-
cess. The objectives of the technology
demonstration were:
1. Evaluate the ability of slurry-phase
bioreactor to degrade polynuclear aro-
matic hydrocarbons (PAHs) present
in the creosote-contaminated soil from
the Burlington Northern (BN) Super-
fund site in Brainerd, MN.
2. Evaluate the performance of the
slurry-phase bioreactor and its re-
moval efficiencies for PAHs and soil
toxicity.
3. Determine the air emissions resulting
from the volatilization in the reactor.
4. Provide technical data to assist EPA
in establishing best demonstrated
available technology (BOAT) stan-
dards for the level of treatment re-
quired before land disposal.
5. Develop information on capital and
operating costs for the full-scale treat-
ment system.
Technology Description
Biological treatment entails degradation
of organic compounds by microorganisms.
The desired end products of aerobic bio-
degradation are carbon dioxide, water, in-
organic salts, and other relatively harm-
less products of microbial metabolism. In
treating hazardous wastes or remediating
contaminated soil, nutrients and microor-
ganisms are often added to enhance bio-
degradation.
This treatment method has several ad-
vantages because an optimal environment
for biodegradation of the organic contami-
nants can be maintained with a high de-
gree of reliability. Biological reactions can
proceed at an accelerated rate in a slurry
system because limiting nutrients can be
supplied and contact between contami-
nants and microorganisms can be in-
creased by effective mixing and mainte-
nance of high bacterial populations.
A slurry-phase process can also be op-
erated as a continuous-flow system since
the impact of toxic waste levels is re-
duced by the instantaneous dilution of the
feed stream as it enters the reactor. In
addition, toxic end products of microbial
metabolism, which may repress bacterial
activity, typically do not accumulate to in-
hibitory levels in the continuous-flow mode.
Specifications of Slurry-Phase
Reactor Used During SITE
Demonstration
The EIMCO Biolift™ Reactor * (nominal
volume of 64-L) used during the SITE
demonstration, shown diagrammatically in
Figure 1, is of stainless steel and is
equipped with agitation, aeration, and tem-
perature controls.
Specifications for the 64-L EIMCO
Biolift™ reactor are:
• Reactor is made of 304 stainless-steel
plate, 3/16-in. thick. Interior tank di-
ameter is 15 in. Total height is 36 in.
Usable volume is approximately 60 L.
• Two airlift pipes and rake arm mecha-
nisms are made of 304 stainless steel.
• Two elastomeric membrane diffusers
are mounted on rake arm. Diffuser
membrane consists of NBR rubber;
other rubber materials are available
depending on application.
• Air to diffusers is supplied via a rotary
air valve. Air to airlift is supplied
through a connection in the bottom
plate of reactor.
'Mention of tradenames or commencal products does
not constitute endorsement or recommendation for
• Drive motor for the rake arm is a
Dayton, permanent-magnet, DC gear
motor: power input 1/12 hp; 0.83
amps; 9.9 rpm; gear ratio 167:1; 228
in. Ib torque; a Dayton Motor Speed
Control 3 amps (max). Power trans-
mission is by a timing belt.
• Drive motor for the impeller is a Day-
ton, permanent-magnet, DC gear mo-
tor: power input 1/10 hp; 0.89 amps;
110 rpm; gear ratio 37:1; 34 in. Ib
torque; a Dayton Motor Speed Con-
trol 3 amps (max). Power transmis-
sion is by timing belt.
• Reactor is heat traced electrically:
chromolox™ on/off proportional tem-
perature controller with digital indica-
tor.
• Axial flow impeller with pitched blades
is mounted on drive shaft.
• Flowmeters for airlift and diffusers are
Dwyer Instruments RMB type.
• All the necessary tabs, fittings, and
plugs allow insertion of DO, pH, and
temperature probes.
• The single stage, single-cylinder,
oilless, diaphragm compressor is Tho-
mas Industries Model 917CA22: 1/8
hp shaded pole motor, single phase;
110v, 60 Hz; or alternatively, a filter
regulator for hook-up to high pres-
sure house air.
• A mechanical foam breaker with 1/6
hp variable speed motor is optional.
The reactor's contents are agitated by
three mechanical methods. First, a rake
mechanism moves the settled material
from the bottom of the reactor to the sec-
ond agitation mechanism, an airlift circula-
tion system, which circulates the material
to the top of the reactor. The third agita-
tion mechanism is a low-shear impeller
located approximately in the center of the
central shaft of the reactor. Aeration is
supplied by a set of air diffusers attached
to the rake arm at the bottom of the reac-
tor. Temperature is maintained by a heat
tape system equipped with a digital read-
out.
The contents of the EIMCO Biolift™ Re-
actor can be sampled in two ways. An
opening at the front top of the reactor
allows access at the top surface of the
liquid. This permits visual inspection of
the mechanical actions within the reactor
as well as data collection with hand-held
instruments that can be inserted into the
slurry from the top. Samples can also be
collected from the three sampling ports
located along the side of the reactor at
three vertical positions along the reactor
wall. Each port represents a distinct zone
of the slurry: the bottom sampling port
provides material from within the rake mix-
ing zone where the heaviest particles are
-------
DiffuserAir Supply
Rotary Valve
Rake Drive Shaft
Support Bearings
Impeller Drive Shaft
Support Bearings
Airlift
Discharge (2)
Airlifts (2)
Sample and
Drain Valves
Aeration Diffusers (2)
(Partially Shown)
Rake Blades (5)
Figure 1. EIMCO Biolift™ Reactor.
likely to be present; the middle sampling
port, from within the most well-mixed zone
of optimal grain size; the top sampling
port, from the layer containing the finest
particles. Samples of contaminated mate-
rial can be taken from each of these three
ports to permit an evaluation of the mixing
efficiency of the reactor.
Overview of the SITE
Demonstration
Five 64-L EIMCO Biolift™ reactors, op-
erated in series mode, were used to test
the degradation of soil-bound PAHs in a
slurry-phase, biologically active matrix.
Creosote-contaminated soil from the BN
site was passed through a 1/2-in. screen
to remove oversized material. After screen-
ing, the soil was mixed with water to form
a 30% slurry. The slurry was then poured
into a ball mill to reduce the particle size
and was screened on exit from the ball
Rake Drive
Gearmotor
Impeller Drive
Gearmotor
Airlift Air Supply
Block Valve
Airlift Water Flush
Connection
Airlift
Check Valve
Impeller Drive Shaft
Impeller
Rake Drive Shaft
Rake Arms
mill through a No. 8 sieve to produce a
slurry with a grain size distribution suit-
able for charging EIMCO Biolift™ reactors.
Following milling, 66 L of the soil slurry
was transferred into each of the five reac-
tors.
After the reactors were charged with
the soil slurry, a concentrated inoculum of
indigenous bacteria was added to each of
the reactors. For optimal microbial activ-
ity, nutrient amendments, including am-
monia, phosphate, magnesium, calcium,
iron, and ammonium molybdate, were
added to the reactors.
Sampling and analysis activities per-
formed during the pilot-scale demonstra-
tion involved collecting composite samples
from each of the reactors for pre- and
posttreatment analyses and sampling
throughout the demonstration to monitor
system operation. During the demonstra-
tion, soil-bound and liquid-phase PAHs,
TPHs, nutrients, pH, DO, temperature, tox-
icity, and microbial activity and phenotype
were monitored. Composite samples were
collected from the three sampling ports
located along the side of each reactor at
three different vertical locations. Soil-slurry
samples were taken from the reactors over
a 12-wk period. In the ninth week of op-
eration, four of the bioreactors were rein-
oculated with an additional 125 ml of the
inoculum to stimulate the PAH degrada-
tion process.
SITE Demonstration Results
In addition to IT'S sampling and analy-
ses described above, ECOVA performed
PAH analyses of soil samples. IT ana-
lyzed samples taken during Weeks T0, T9,
and T12 to determine PAH concentrations
by use of a gas chromatography/mass
spectroscopy (GC/MS) method. ECOVA
used a high performance liquid chroma-
tography (HPLC) method in the analysis
of samples taken during Weeks T0, T.,,
T2, T3, T4, T6, T9, T10, T1V and T12. The
results obtained from each method are
described and compared in the following
subsections.
Results of Pretreatment and
Posttreatment Soil Samples
Analyzed by Gas
Chromatography/Mass
Spectroscopy (GC/MS) Method
The pre- and posttreatment soil and
liquid samples were analyzed for critical
contaminants PAHs and TPH. The air
samples were analyzed for volatile and
semivolatile organics (VOCs and SVOCs)
and total hydrocarbons (THCs). All the
PAH analyses on soil and liquid samples
were performed by the EPA-approved GC/
MS method (SW-846, Method 8270).
The pretreatment samples were col-
lected at the start of testing (Week T0) to
determine the baseline concentration of
the critical semivolatile contaminants in
the soil treatment. The posttreatment
samples were collected 9 wk (T9) and 12
wk (T12) after the start of testing to deter-
mine the levels of the critical contami-
nants remaining in the soil after treatment.
The concentrations of the PAH con-
taminants in the pretreatment soil samples
ranged from 5.5 to 840 mg/kg. The con-
centration of total, 2- and 3-ring, and 4-
through 6-ring PAH level and the degra-
dation rates determined by GC/MS are
given in Tables 1 and 2. The concentra-
tions of the PAHs in posttreatment samples
indicated a significant reduction of PAHs
in the soil matrix. The percent reduction of
total PAH for Week T12 samples for the
five reactors ranged from >72.4% in Re-
-------
Table 1. Concentrations of Total, 2- and3-Ring,
and 4- through 6-Ring PAH Levels in
Soil Samples, Determined by GC/MS,
mg/kg
Week
Reactor
12
2-and 3-Ring PAHs
Reactor 1
Reactor 2
Reactor 4
Reactor 5
Reactor 6
Total
2299
1418
390.5
2644
7186
14940
<31.4
5.5
<32.3
31.5
18
<23.7
<49.5
<23.8
8.1
<46.3
<44.7
<34.5
4- through 6-Ring PAHs
Reactor 1
Reactor 2
Reactor 4
Reactor 5
Reactor 6
Total
Total PAHs
Reactor 1
Reactor 2
Reactor 4
Reactor 5
Reactor 6
Total
1410
775
288
1836
502
962.2
3709
2193
678.5
4480
1220.6
2456.2
<273.7
<65.2
<357.9
<308.9
182.3
<237.6
<305. 1
<70.7
<390.2
<340.4
200.3
<261.3
316.4
<267.5
<91.3
404.6
<291.8
274.3
<365.9
<291.3
<99.4
<450.9
<336.5
308.8
Table 2. Percent Degradation of Total, 2- and
3-Ring, and 4- through 6-Ring PAH
Levels in Soil Samples, Determined by
GC/MS
Reactor
Week
12
2- and 3-Ring PAH Degradation Rate
Reactor 1 >98.63 >97.85
Reactor 2 99.61 >93.32
Reactor 4 >91.73 97.93
Reactor 5 98.81 >98.25
Reactor 6 97.50 >93.78
Mean Percent >98.41 >97.69
4- through 6-Ring PAH Degradation Rate
Reactor 1 >80.59 77.56
Reactor 2 >91.59 >65.48
Reactor 4 >-24.3 >68.30
Reactor 5 >83.18 77.96
Reactor 6 63.69 >41.87
Mean Percent >75.31 >71.49
Total PAH Degradation Rate
Reactor 1 >91.77 >90.10
Reactor 2 >96.77 >86.72
Reactor 4 >42.50 >85.35
Reactor 5 >92.40 >89.94
Reactor 6 83.59 >72.43
Mean Percent >89.36 >87.43
actor 6 to >90.1% in Reactor 1. Results
indicate that an average of greater than
87% of total PAHs were degraded over all
five operating reactors after the 12th week
of the demonstration period.
Initial levels of the hazardous compo-
nent of creosote PAHs were 2460 mg/kg,
as determined by GC/MS. After 12 wk of
treatment, the concentration of the easily-
degraded 2- and 3-ring compounds had
declined by >98% from 1490 mg/kg to
<35 mg/kg (average of five reactors). The
concentration of the much more intrac-
table 4-, 5- and 6-ring compounds de-
clined >72% from 960 mg/kg to <270 mg/
kg (average of five reactors).
The more complete degradation of the
lower molecular-weight PAHs may reflect
higher bioavailability of 2- and 3-ring PAHs
than of 4- through 6-ring PAHs. Four- and
higher-ring PAHs are considerably less
soluble than simpler ring-PAHs.
The degradation rates of the different
PAHs varied appreciably during the course
of the study and reflect changes in the
reactor environments. After 9 wk of test-
ing, Reactors 2 and 4 were inoculated
with fresh bacterial populations, and Re-
actors 5 and 6 were both reinoculated
and amended with the surfactant Tween
80. Reactor 1 was not amended in any
way. Results from Week 12 indicate that
additional spiking during Week 9 did not
assist in further degradation of the com-
plex PAHs. On the contrary, the level of
contamination due to the presence of the
more complex PAHs was greater in Week
12 than in Week 9. The lower level of
PAH contamination in Week 9 soil samples
may have resulted from laboratory proce-
dures. To extract PAHs, the analytical labo-
ratory used a sonication method (EPA
Method 3550) that calls for a 2-min soni-
cation period. This may not have been
enough time for the entire soil sample to
intimately contact the extraction solvents
and may have led to some inconsistent
results for higher ring PAHs.
IT monitored TPH by infrared spectros-
copy analysis over the course of the study.
The concentration of TPH declined by
89.3% after 12 wk of treatment. The data
for soil-bound TPH indicate that, as with
the PAH data, variations occurred in TPH
levels in the slurry (Table 3) during the
12-wk treatment. As with the PAHs, the
greatest decline in TPH occurred in the
first 2 wk of the study. A rise in the levels
of TPH occurred at Week T6; however,
this is 2 wk after total PAHs rose in the
slurries. This delay could reflect the actual
production of TPH compounds as meta-
bolic products of the biodegradation of the
PAHs. It could also reflect a simple rise in
extraction efficiency resulting from soil par-
ticle comminution.
GC/MS Analytical Results of
Pretreatment and Posttreatment
Liquid Samples
The concentrations of the PAH con-
taminants in the pretreatment liquid
samples ranged from 0.006 to 18 mg/L.
The concentrations for the majority of
PAHs in the posttreatment samples were
below the established method detection
limits (MDLs) for the instruments. After 9
wk of treatment, only the more recalcitrant
complex PAHs remained in the liquid ma-
trix. These contaminants ranged in con-
centration from 0.013 to 0.14 mg/L. Re-
sults from Week 12 indicated a further
reduction in liquid phase contaminants as
the levels of PAHs in the soil were further
diminished, and the MDLs for the con-
taminants from Week 12 were lower than
those for Week 9.
Results of Pretreatment and
Posttreatment Soil Samples
Analyzed by HPLC Method
The ECOVA Laboratory employed
HPLC (ECOVA modified EPA SW-846,
Method 8310) to analyze for PAHs. The
baseline soil (Week T0) characterization
showed that naphthalene, acenaphthene,
and fluoranthene are the constituents
present at the highest levels (range of
2170 + 250 ppm), followed by fluorene
and benzo(a)anthracene (range of 960 +
8 ppm). Total PAH levels in these soils
are 10,970 ppm. The 2- and 3-ring PAHs
constitute 5890 ppm of the total, and the
4- through 6-ring PAHs account for 5080
ppm.
The PAH degradation rates over all five
operating reactors during the 12-wk study
are presented in Table 4. As seen in Table
Table 3. Concentrations of Total Petroleum Hydrocarbons (TPH) in Soil, mg/kg
Week
Reactor
11
12
1
2
4
5
6
35000
17500
13000
16000
19500
7200
2600
2700
3600
2400
1800
1800
1600
2300
2400
3100
2300
2100
2900
3600
1800
3200
1800
1700
2200
1900
1700
1700
3700
4900
1700
1800
1900
2700
2700
-------
4, after the initial 2 wk of slurry-phase
treatment, 90% of the total PAHs were
degraded. Degradation rates (mg/kg/wk)
for 2- and 3-ring PAHs were somewhat
higher at 2 wk (96%) than they were for 4-
through 6-ring PAHs (83%). The final lev-
els at Week T12 were 653.5 mg/kg for
total PAHs, 152.1 mg/kg for 2- and 3-ring
PAHs, and 501.4 mg/kg for 4- through 6-
ring PAHs.
Comparison of Analytical
Results Obtained by GC/MS
and HPLC Methods
The GC/MS results indicate total PAHs
were degraded by more than 87% for all
reactors during a 12-wk study. Degrada-
tion rates for 2- and 3-ring PAHs (over
98%) were much higher than they were
for 4- through 6-ring PAHs (72%). These
observations (based on GC/MS data)
agree with those obtained in the ECOVA
HPLC study. The HPLC results show 94%
reduction of total PAHs, 97% reduction of
2- and 3-ring PAHs, and 90% reduction of
4- through 6-ring PAHs. Figures 2 and 3
compare the mean total PAH concentra-
tion at Weeks T0, T9, and T12, as deter-
mined by GC/MS and HPLC.
Results of Air Monitoring
Air monitoring of THCs, SVOCs, and
VOCs was performed continuously for the
first few days of the demonstration. The
VOCs and SVOCs were monitored peri-
odically through the ninth week. THC emis-
sions data show high emissions the first 2
days of process operation, followed by a
steady decline to baseline recordings by
the fifth day of operation. The VOC volatil-
ization was high the first 2 days of opera-
tion, decreasing to near analytical detec-
tion limits by the third day of operation.
The SVOC emissions (naphthalene, 2-
methylnaphthalene, acenaphthylene,
acenaphthene, dibenzofuran, fluorene,
phenanthrene, and anthracene) were de-
tectable during the first 4 days of sam-
pling. Beginning the sixth day of opera-
tion, very small quantities (at or below
detection) of semivolatiles were found.
Slurry Toxicity Reduction
Microtox™ analysis was performed over
the course of the study to monitor toxicity
levels of the slurried soil to determine if
soil toxicity decreased during slurry-phase
biological treatment. The general trend in
toxicity declined over the 12 wk. After 4
wk of treatment, some toxicity was still
present in all the reactor slurries; and by
Week 9, Reactors 5 and 6 still appeared
to have some residual toxicity. By Week
10, either marginal or no toxicity was as-
sociated with the slurries.
Table 4. Percent Total, 2- and 3-Ring, and 4- through 6-Ring PAH Degradation Rates in Soil
Samples Analyzed by HPLC •
Week
Reactor
2- and 3-Ring
Reactor 1
Reactor 2
Reactor 4
Reactor 5
Reactor 6
Mean Percent
1
PAH
98.53
84.25
56.64
81.82
88.79
2
92.87
97.39
97.17
95.52
96.40
96.14
3
99.14
99.10
99.38
97.74
98.29
4
84.41
95.98
97.76
90.43
97.15
6
99.28
96.54
95.02
98.16
99.39
9
98.56
98.11
98.15
97.74
97.83
98.06
10
98.71
98.82
95.41
91.54
99.22
11
86.28
92.00
91.77
97.87
99.50
12
98.21
98.45
98.43
93.36
97.25
97.42
4- through 6-Ring PAH
Reactor 1
Reactor 2
Reactor 4
Reactor 5
Reactor 6
Mean Percent
Total PAH
Reactor 1
Reactor 2
Reactor 4
Reactor 5
Reactor 6
Mean Percent
35.54
34.10
-79. 1 1
28.65
47.60
61.86
60.15
-10.75
56.72
71.34
70.41
83.46
87.28
80.83
85.90
82.89
82.86
90.70
92.26
88.58
91.95
90.00
87.37
91.56
93.79
83.36
83.35
93.89
95.48
96.61
90.95
91.96
50.80
77.56
90.22
60.76
83.35
69.42
87.13
94.02
76.43
91.30
88.15
80.13
72.28
64.95
93.53
94.31
88.65
83.73
82.48
96.91
93.23
91.86
93.19
83.65
95.59
92.22
96.18
95.10
95.69
91.09
96.88
95.35
86.65
90.30
92.37
86.64
91.99
93.33
94.73
93.90
89.23
96.16
85.11
91.16
92.72
80.54
88.50
85.76
91.60
92.24
89.69
94.84
86.16
92.41
94.32
82.34
90.07
90.13
92.83
95.55
96.39
88.16
94.21
94.04
Conclusions
Based on results of the slurry-phase
biological treatment SITE demonstration,
the following conclusions can be made
regarding the performance of the technol-
ogy:
• The percent reduction of soil-bound
PAHs (analyzed by GC/MS) over 12
wk of testing demonstrated an aver-
age reduction of >72% for 4-through
6-ring PAHs to >98% for 2- and 3-
ring PAHs; the reduction of total PAHs
exceeded 87%.
• The average percent reduction of TPH
was 89.3% after 12 wk of treatment.
• Emissions data show high emissions
of THC the first 2 days of process
operation, followed by a steady de-
cline to baseline recordings by the
fifth day of operation. The VOC vola-
tilization was high the first 2 days of
operation, decreasing to near analyti-
cal detection limits by the third day of
operation. The SVOC emissions were
detectable during the first 4 days of
sampling. Beginning the sixth day of
operation, very small quantities (at or
below detection) of semivolatiles were
found.
• Slurry toxicity decreased to marginal
or no toxicity by the tenth week of
treatment.
• The total cost incurred by IT and
ECOVA during the demonstration was
approximately $333,800. Because of
the BOAT status of this demonstra-
tion, extensive chemical analyses
were required. In an actual site op-
eration, this cost could be greatly re-
duced by limiting the analytical goals.
Based on available full-scale cost
data, the cost of full-scale
remediations typically range from $50-
$250/yd3.
aHPLC = High performance liquid chromatography.
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4500
10
12
Figure 2. Total PAH levels in reactor soil samples as determined by GC/MS
16000
14000
12000
10000
8000
6000
4000
2000
10
12
Figure 3. Total PAH levels in reactor soil samples as determined by HPLC.
if U.S. GOVERNMENT PRINTING OFFICE: 1993 • 750-071/80065
-------
Ronald Lewis (the EPA Project Officer, see below) is with the Risk Reduction
Engineering Laboratory, Cincinnati, OH.
The complete report, entitled 'Technology Evaluation Report: Pilot-Scale
Demonstration of a Slurry Phase Biological Reactor for Creosote-Contami-
nated Soil," (Order No. PB93-205 532/AS; Cost: $27.00, subject to
change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
A related report, entitled "Applications Analysis Report: Pilot-Scale Demonstra-
tion of a Slurry Phase Biological Reactor for Creosote-Contaminated Soil,"
discusses the applications of the demonstrated technology.
The EPA Project Officer can be contacted at:
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
EPA/540/S5-91/009
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