xvEPA
SITE FACTS
United States
Environmental Protection
Agency
Office of Research and
Development
Washington, DC 20460
Office of Solid Waste and
Emergency Response
Washington, DC 20460
EPA/540/F-93/510A
September 1993
Bioremediation Field
Initiative Site Profile:
Libby Ground Water
Superfund Site
°7< Location: "Libby, Montana * ,
Laboratories/Agencies: U.S.
^ EPA Roberts. Kem > ' ' '
J» Environmental Research'
' Laboratory (RSKERL), Utalx '
" ''State University (USU)', U.S." - /
y.-EPA Region 8;-'/ ' -
; Media and Contaminants^ :
'% 'Pentadilorophenol (PCP) and
•' polycyelic aromatic
t "r hydrocarbons (PAHs) in soil' and"
ground water -_ ''•-,,
'' Treatrnent: Surface soil' ' * ',
/•''bioremediation, aboveground ' '*
X», fixed-film bioreactor, in situ ••
t~ bioremediation //,/''
.',' Date of Initiative Selection:
-^Objective: To evaluate the, ,*
t" p'erformance of three,
%^biotreatment processes for
:,'J degradation of PCP and PAHs
Bioremediation Field Initiative
;. Contact: Scott Huling, U.S. ./
t'-EPA^RSKERL, P.O. Box 1198, -' ' '
'"\Ada; OK 74820 ' , - /
„ ,,
r Regional Contact: Jim Harris,
v U.S. EPA Region 8, Montana
'.* Office, 301 Sopth Park, Federal , s
,' Building, Dravver-10096, Helena, *
/ MT59626\!' °' ' ' '
- *
Background
The Libby Ground Water Superfund site in Libby, Montana, is located
in part at the site of an operating lumber mill currently owned by
Champion International Corporation. A wood preserving facility for-
merly operated at the site contaminated soil and ground water with
two wood preservatives: pentachlorophenol (PCP) and creosote
(PAHs). PAHs are the primary contaminants of concern associated
with the soil phase. PAH-contaminated soils from three primary
source areas have been excavated and moved to a central waste pit.
The U.S. EPA Robert S. Kerr Environmental Research Laboratory
(RSKERL), in cooperation with Utah State University (USU), is carry-
ing out a performance evaluation of three biological treatment pro-
cesses at the Libby site: (1) surface soil bioremediation in a lined,
prepared-bed land treatment unit (LTD); (2) ground water treatment
"t
" Contaminant
Plume
Waste Pit Area
Infiltration Trench
LTU
LTU
^ Scale^teatl ^
0 300 600
T-, Regional
KxGround Water
Flow
• Monitoring Well
O Extraction Well
X>
> Injection Well
Figure 1. Plan view showing ITU, bioreactor, and ground water injection system (from
Piotrowski, M.R. 1991. Full-scale in situ bioremediation at a Superfund site: a progress
report. Second Annual West Coast Conference, Hydrocarbon Contaminated Soils and
Ground Water. Newport Beach, CA. Afarch 1991).
Printed on paper that contains at least
50 percent recycled, fiber.
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in an aboveground fixed-film bioreactor; and (3) in
situ bioremediation of the upper aquifer. Each
process is being evaluated with regard to design,
operation, monitoring, and performance. Figure 1
is a plan view of the site, showing the LTU, biore-
actor, and ground water injection systems.
Field Evaluation
Surface Soil Bioremediation. The LTU consists of two
adjacent 1-acre cells, lined with low-permeability
materials to minimize leachate infiltration from the
unit (see Figure 2). Contaminated soil is applied to
the cells in 9-in. lifts and treated until target con-
taminant levels are achieved within each lift. Evalu-
ation of the effectiveness of the land treatment
includes sampling the soil in the LTU, studying
field-scale treatment and toxicity reduction, analyz-
ing the influence of moisture and soil structure, and
calculating the mass balance of contaminants in
terms of soil and leachate.
Figure 2. Land treatment unit.
LTU soil analysis data will be used to determine the
statistical significance, confidence, and extent of
biodegradation at this site. Degradation kinetics
and toxicity reduction studies will generate data
that can be used to help assess overall bioremedia-
tion effectiveness and predict performance of simi-
lar bioremediation processes at other sites.
Aboveground Fixed-Film Bioreactor. Aboveground
treatment of ground water occurs in two fixed-film
reactors, which operate in series. The effluent from
these reactors is amended with nutrients and reoxy-
genated prior to reinjection through an infiltration
trench. The Initiative will be monitoring the per-
formance of the bioreactors, including flow compo-
sited sampling, analysis of biofilm dynamics,
calculation of mass balance of contaminants, and
treatment optimization.
In Situ Bioremediation of the Aquifer. The in situ biore-
mediation system involves addition of hydrogen
peroxide and inorganic nutrients to stimulate
growth of contaminant-specific microbes. Evalu-
ation of this process will include determining dis-
solved oxygen profiles across the site, sampling
aquifer material to identify contamination and cor-
relate microbial content, distinguishing between
abiotic and biotic effects, and correlating dissolved
oxygen uptake with biodegradation and toxicity
reduction.
Status
Currently, remediation of each lift of soil applied to
the LTU takes 32 to 163 days. Based on these re-
sults, it is predicted that remediation of the 45,000
yd3 of contaminated soil will take 8 to 10 years.
Preliminary performance data on the fixed-film
bioreactors indicate that PAH and PCP removal is
taking place. Aquifer core samples have a chemi-
cally reduced condition, indicating that the site has
an abiotic as well as a biological oxygen demand.
Investigators plan several tests to differentiate be-
tween the abiotic and biotic oxygen demands..
The Initiative's objectives are to more fully document the performance of full-scale applications of bioremediation; provide "
technical assistance to regional and state site managers; and provide information on treatability studies,'design, and operation ojf,
bioremediation projects. The Initiative currently is performing field evaluations.of bioremediation at eight other hazardous waste
sites: Park City Pipeline, Park City, KS; Bendix Corporation/Allied Automotivejuperfund site, St. JoseplvMI; West KL Avenue ,
Landfill Superfund site, Kalamazoo, MI; Eielson Air Force.Base Superfund site, Fairbanks, AK; Hill Air Fdfce Base Superfund site/
Salt Lake City, UT; Escambia Wood Preserving Site—Brookhaven, Brookhaven/MS; Reilly Tar and Chemical Corporation Super-;
fund site, St. Louis Park, MN; and Public Service Company^ Denver,,CO, To obtain profiles on these additional sites or Tto be,added
to the Initiative's mailing list, call 513-569-7562. For further information on fhe Bioremediation Field Initiative', contact FranKremer,
Coordinator, Bioremediation Field Initiative, U.S. EPA, Office of Research 'and'Developmenlpze West Martin Luther King Drive,,
Cincinnati, OH 45268; or Michael Forlini, U.S. EPA, Technology Innovation Office, Office of Solid Waste and Emergency Response^ *,
401MStreet,SW.,Washington,DC20460. •' -- V ' ' '*> ., »*> >- >i < - ' ., , •%- >> <,'» <•, - ';'
'' * ' " - > • >
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