United States
Environmental Protection
Agency
Research and
Development
(RD681)
EPA/540/A5-91/001
September 1991
&EPA
Biological Treatment of
Wood Preserving Site
Groundwater by BioTrol, Inc.
Applications Analysis Report
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
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EPA/540/A5-91/001
September 1991
Biological Treatment of Wood Preserving Site
Groundwater by BioTrol, Inc.
Applications Analysis Report
Risk Reduction Engineering Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, OH 45268
Printed on Recycled Paper
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Notice
The information in this document has been funded by theU.S. Environmental Protection
Agency under the auspices of the Superfund Innovative Technology Evaluation (SITE)
Program under Contract No. 68-03-3485 to Science Applications International Corporation.
It has been subjected to the Agency's peer and administrative review, and it has been
approved for publication as an EPA document. Mention of trade names or commercial
products does not constitute an endorsement or recommendation for use.
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Foreword
The Superfund Innovative Technology Evaluation (SITE) Program was authorized in
the 1986 Superfund Amendments. The Program is a joint effort between EPA's Office of
Research and Development £ind Office of Solid Waste and Emergency Response. The
purpose of the program is to assist the development of hazardous waste treatment technolo-
gies necessary to implement new cleanup standards which require greater reliance on
permanent remedies. This is accomplished through technology demonstrations designed to
provide engineering and cost data on selected technologies.
This project consisted of a demonstration of BioTrol, Inc.'s fixed-film, amended
biological treatment process arid an analysis of the effectiveness of the system. The study was
carried out at the MacGillis and Gibbs Company site in New Brighton, MN, a site where wood
preserving operations have been carried out over several decades using each of the traditional
preserving chemical systems: first creosote, later pentachlorophenol, and most recently,
chromated copper arsenate. In 1984 the site was added to the National Priorities List as one
where soil and groundwater were contaminated with hazardous chemicals. The goals of the
study, summarized in this Applications Analysis Report and described in more detail in the
companion Technology Evaluation Report, were to evaluate the technical effectiveness and
economics of a specific biological treatment process for the elimination of pentachlorophe-
nol (and polynuclear aromatic: hydrocarbons found in creosote) from groundwater and to
establish the potential applicability of the process to other wastes and/or other Superfund and
hazardous waste sites.
Additional copies of this report may be obtained at no charge from EPA's Center for
Environmental Research Information, 26 West Martin Luther King Drive, Cincinnati, OH
45268, using the EPA document number found on the report's front cover. Once this supply
is exhausted, copies can be purchased from the National Technical Information Service,
Ravensworth Bldg., Springfield, VA, 22161, 703-487-4650. Reference copies will be
available at EPA libraries in their Hazardous Waste Collection. You can also call the SITE
Clearinghouse hotline at 1-800-424-9346 or 202-382-3000 in Washington, DC, to inquire
about the availability of other reports.
C-
; _
E. Timothy Oppelt, Director
Risk Reduction Engineering Laboratory
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Abstract
This document is an evaluation of the BioTrol, Inc., Aqueous Treatment System
(BATS), a fixed-film, aerobic biological treatment process for contaminated groundwaters
and other wastewaters.
This report summarizes and analyzes the results of the Superfund Innovative Technol-
ogy Evaluation (SITE) Program's six week demonstration at the MacGillis and Gibbs
Company wood preserving site in New Brighton, MN. Other pertinent data from BioTrol
investigations are included to support the demonstration results. Conclusions were reached
concerning the technological effectiveness and economics of the process and its suitability
for use at other sites.
During the SITE demonstration, operations and sampling and analysis were carefully
monitored to establish a database against which the vendor's claims for the technology could
be evaluated reliably. These claims were that the BATS could achieve 90% removal of
pentachlorophenol (PCP) and polynuclear aromatic hydrocarbons (PAHs) and that penta
removal was by mineralization.
The conclusions from the pilot scale demonstration study and other available data are:
(1) the fixed film aerobic process is capable of degrading pentachlorophenol (PCP) and other
organic pollutants to more than 95% removal; (2) effluent concentrations of PCP well below
1 mg/L are attainable, if necessary by increasing the retention time, i.e., decreasing the
throughputrate; (3) removal of PCP is largely by mineralization to carbon dioxide, water and
saltbased on chloride yields; (4)acutetoxicity of thePCP-contaminatedgroundwater.atleast
to minnows and water fleas, is eliminated; (5) operating cost for labor, chemicals, and energy
range from $3.45/1000 gal at 5 gpm to $2.43/1000 gal at 30 gpm and total capital and
operating cost can be as low as $2.94/1000 gallons, and (6) other factors, including ambient
temperature and the presence of other contaminants in the feedwater, may affect total cost and
operating efficiency.
IV
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Contents
Notice ii
Foreword iii
Abstract iv
Figures.... vii
Tables viii
Abbreviations and Symbols ix
Conversion Factors x
Acknowledgments ....xi
1. Executive Summary 1
Introduction •. 1
Conclusions 1
Discussion of Conclusions i
2. Introduction 3
The Site Program 3
Site Program Reports 3
Purpose of the Applications Analysis Report 4
Key Contacts 4
3. Technology Applications Analysis 5
Introduction 5
Conclusions 5
Discussion of Conclusions 5
Applicable Wastes 6
Site Characteristics 7
Environmental Regulation Requirements 7
Materials Handling Requirements 7
Personnel Issues 8
Testing Issues t g
4. Economic Analysis 9
Introduction 9
Conclusions 9
Issues and Assumptions 9
Basis for Economic Analysis 10
Results 12
5. Bibliography 15
Appendices 17
A. Process Description 17
Introduction 17
Process Description 17
BioTrol Soil Washing Process 18
Field Immunoassay for Pentachlorophenol 18
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B. Vendor's Claims 20
Introduction * -20
Technology Description 20
Applicability 21
Case Studies 21
Summary 22
C. SITE Demonstration Results 24
Introduction 24
Field Activities • 25
Test Procedures 25
Results 27
D. Case Studies
1. Full Scale Wood Preserving Site 33
2. Tape Manufacturer-California 36
3. BATS Treatment of BTEX-Minnesota 37
4. Pilot Plant BATS-Minnesota 38
VI
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Figures
A-l Corrugated polyvinyl chloride media .»., •. , 18
A-2 BioTrol Inc.'s, mobile aqueous treatment system , •. 18
A-3 Schematic of BATS system 19
A-4 Schematic of bioreactor •...„ «..ii..i..i19
B-l Benzene treatment by BATS .....,...„> ..;21
B-2 Phenols removal by BATS 22
C-l MacGillis & Gibbs site 25
C-2 WeU construction ,.....„ 26
C-3 BioTrol aqueous treatment system (BATS) with sampling points shown. ..27
D-l Phenolics removal in commercial BATS , , ..........;..34
D-2 PAH removal in commercial BATS „ ,...,.., 35
VII
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Tables
B-l
B-2
C-l
C-2
C-3
C-4
C-5
C-6
C-7
C-8.
C-9.
C-10.
C-ll
C-12.
C-13.
D-l.
D-2.
D-3.
D-4.
D-5.
D-6.
D-7.
Treatment of Solvent-Contaminated Process Water
BATS Performance Data
Analysis of Wells on MacGillis and Gibbs Site ,
Temperature Across BioTrol System
Average TSS and Oil Across the BioTrol System
Average Pentachlorophenol Removal by BioTrol System
Mass Removal of Pentachlorophenol
Comparison of Chloride and TOC Changes with PCP Removal
Potential Chloride Contributions from Partially Chlorinated Phenols
Sludge Analysis Results
PAHs in Air Emissions from Bioreactor
Dioxins/Furans Found in System
Dioxins/Furans Found in Sludge
Metals Found in System
Acute Biotoxicity of Groundwater and Treated Effluent
Characteristics of Phenol Process Water
Wood Preserving Wastewater Treatment by BATS
Operating Cost for BATS Commercial Unit
BATS Removal Efficiency - Tape Process Water
Operating Cost for 10 gpm BATS System
BTEX Treatment with the BATS
Groundwater Treatment in 30 sal Packed Reactor
21
23
26
28
29
29
29
30
30
31
31
31
32
32
32
33
33
34
36
36
37
39
VIII
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Abbreviations and Symbols
BATS BioTrol Aqueous Waste Treatment System
BOD biochemical oxygen demand (mg oxygen/liter)
BTEX benzene, toluene, ethyl benzene, and xylenes
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act of 1980
cfm cubic feet per minute
COD chemical oxygen demand (mg oxygen/liter)
EMSL Environmental Monitoring Systems Laboratory
GC/MS gas chromatograph/mass spectrometer
gpd gallons per day
gpm gallons per miniate
HPLC high pressure liquid chromatograph
HSWA Hazardous and Solid Waste Amendments to RCRA -1984
kwh kilowatt-hour
LC(50) lethal concentration to 50% of a test species population
Mgd million gallons per day
mg/L milligrams per liter
ng/kg nanograms per kilogram
ng/L nanograms per liter
NPL National Priorities List
O/G oil and grease
ORD Office of Research and Development
OSHA Occupational Safety and Health Administration or Act
OSWER Office of Solid Waste and Emergency Response
PAHs polynuclear aromatic hydrocarbons
PCP pentachlorophenol
PEL Permissible Exposure Limit
POTW publicly owned treatment works
ppb parts per billion
ppm parts per million
psi pounds per square inch
PVC . polyvinyl chloride
QA/QC quality assurance/quality control
RCRA Resource Conservation and Recovery Act of 1976
RI/FS Remedial Investigation/Feasibility Study
RREL Risk Reduction Engineering Laboratory
SAIC Science Applications International Corporation
SARA Superfund Amendments and Reauthorization Act of 1986
SITE Superfund Innovative Technology Evaluation
TCPs tetrachlorophenols
TOC total organic carbon (mg carbon/liter)
TSS total suspended solids (mg solids/liter)
ix
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Conversion Factors
English (US)
Area: 1 ft2
lin2
Flow Rate: 1 gal/min
1 gal/min
1 Mgal/d
1 MgaVd
1 Mgal/d
Length: 1 ft
lin.
lyd
Mass: 1 Ib
lib
Volume: 1 ft3
1ft3
Igal
Igal
ft = foot, ft2 = square foot, ft3 = cubic foot
in. = inch, in2 = square inch
yd = yard
Ib = pound
gal = gallon
gal/min (or gpm) = gallons per minute
Mgal/d (or MGD) = million gallons per day
m = meter, m2 = square meter, m3 = cubic meter
cm = centimeter, cm2 = square centimeter
L = liter
g = gram
kg = kilogram
m3/s = cubic meters per second
L/s = liters/sec
m3/d = cubic meters per day
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Factor
9.2903 xlO-2
6.4516
6.3090 xlO-5
6.3090 xlO"2
43.8126
3.7854 x 103
4.3813 x 10-2
0.3048
2.54
0.9144
4.5359 x 102 ,
0.4536
28.3168
2.8317 x lO'2
3.7854
3.7854 x 10-3
= Metric
= m2
= cm2
= m3/s
= L/s
= L/s
= m3/d
= m3/s
= m
= cm
= m
--* 2
= kg
™ L
= m3
— !_,
= m3
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Acknowledgments
This report was directed and coordinated by Mary K. Stinson, EPA SITE Project
Manager in the Risk Reduction Engineering Laboratory—Cincinnati, Ohio. It was prepared
for EPA's Superfund Innovative Technology Evaluation (SITE) Program by Herbert S.
Skovronek and William Hahn of Science Applications International Corporation for the U.S.
Environmental Protection Agency under Contract No. 68-03-3255.
The cooperation and participation of Thomas J. Chresand and supporting staff of
BioTrol, Inc. throughout the course of the project and in review of this report are gratefully
acknowledged, as is the assistance of A J. Bamby of MacGillis and Gibbs. Mark Lahtinen of
the Minnesota Pollution Control Agency (MPCA) and Rhonda McBride, Linda Kern, and
Darryl Owens, the Remedial Project Managers of USEPA's Region V provided invaluable
assistance and guidance in initiating the project and in interpreting and responding to
regulatory needs of the projm. Ronald Lewis and Gordon Evans of USEPA's Risk
Reduction Engineering Laboratory and Linda D. Fiedler of the Technology Innovation
Office of OS WER provided invaluable reviews of the draft report. Finally, the project could
not have been carried out without the tireless efforts of the many S AIC and Radian field and
laboratory personnel.
XI
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Section 1
Executive Summary
Introduction
BioTrol, Inc.'s Aqueous Treatment System (BATS) has
been used to treat a pentachlorophenol-contaminated ground-
water stream at a site on the Superfund National Priorities
List. Operational and cost data were collected for that investi-
gation and serve as a basis for an evaluation of the utility of
this biological process for remediation of other sites across the
Nation. Supporting data from other studies and evaluation of
the process at other sites are discussed in Appendix D.
Conclusions
Based on the results of the SITE demonstration project at
the MacGillis and Gibbs site in New Brighton, MN and
information concerning other studies provided by the vendor,
BioTrol, Inc., for different wastes at other sites, several con-
clusions can be drawn.
• The fixed-film biological treatment system is capable of
destroying substantially all pentachlorophenol (95%+) and
the major portion (>80%) of other phenolics fin wastewater
from wood preserving sites.
• Destruction of >95% can be achieved for a range of other
pollutants, including other halogenated hydrocarbons, ben-
zene, toluene, ethyl benzene, and xylenes (BTEX) from
gasoline, and oxygenated solvents, with final concentra-
tions of specific pollutants well below 1 mg/L achievable
in some cases.
• Specifically, with input levels of <50 mg/L pentachloro-
phenol, destruction of 99% and final pentachlorophenol
concentrations well below 1 mg/L are achievable at low
throughput rates and removals of 95+% are achievable at a
flow rate of 5 gpm, equivalent to a residence time of 1.8
hours.
• Biodegradation is the predominant mechanism for elimi-
nation of pentachlorophenol. Losses by air stripping and
adsorption on solids are very minor contributors to penta-
chlorophenol removal.
• Removal of other pollutants commonly found in contami-
nated waters at wood treatment facilities (e.g., polynuclear
aromatic hydrocarbons) does occur based on results of
other BioTrol studies but could not be coniiirmed in the
SITE demonstration due to the relatively low concentra-
tions in the influent groundwater. The removal mechanism
for polynuclear aromatic hydrocarbons is probably a com-
bination of biodegradation and adsorption on solids.
• Other constituents commonly encountered at such sites,
including oils, suspended solids, and heavy metals, do not
appear to have an adverse effect on bioreactivity. Exces-
sive levels of these contaminants can be removed by
conventional pretreatment if necessary.
• Biological treatment and removal of pentachlorophenol
markedly reduces acute biotoxicity of the wastewater,
making it suitable for direct discharge, introduction to a
POTW, or reuse.
• The operating cost for the fixed-film biological treatment
is in the range of $2.43 to $3.45/1000 gallons, depending
on system size. Major contributors to cost are labor and
heat requirements, with the labor contribution decreasing
significantly as the scale increases.
• One advantage of the BioTrol process over other biologi-
cal treatment processes is that it does not generate residues
or emissions that would hamper its use, significantly in-
crease operating cost, or require capital investment for
solids separation.
• Auxiliary equipment that could be needed to support this
process are comparable to that which would be needed for
other above ground treatment systems, such as oil/water
separators and clarifiers for pretreatment and filters, car-
bon adsorbers, etc. for effluent polishing to meet discharge
requirements.
• With proper acclimation and appropriate bacterial inocula-
tion, the system should be well suited to the treatment of
wastewaters (groundwater, process wastes, lagoon leak-
age, etc.) containing a wide range of pollutants.
Discussion of Conclusions
A mobile (trailer-mounted) system with 5 gpm capacity
was tested at the MacGillis and Gibbs Company site under the
Superfund Innovative Technology Evaluation (SITE) pro-
gram. Extensive data were collected over a six week period to
assess the ability of the system to remove pentachlorophenol
1
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and polynuclear aromatic hydrocarbons from groundwater
drawn from an aquifer at the site; the operational requirements
of the system; and the cost of operation. The data from this
study serve as the primary basis for the foregoing conclusions.
Additional supporting evidence was provided for other field
studies by BioTrol.
An extensive Quality Assurance (QA) program was con-
ducted by SAIC in conjunction with EPA's QA program,
including audits and data review along with corrective action
procedures and special studies to resolve specific data quality
problems. This program is the basis for the quality of the data
derived from the SITE project Discussion of the QA program
and the results of audits, data reviews, and special studies can
be found in the Technology Evaluation Report.
With the input water essentially fixed in its pollutant
composition, the primary variable that was studied was flow
rate through the system. Three flow rates were selected and
the system was evaluated for about two weeks at each "steady
state" to provide a sound data base. Extensive data were
collected on primary pollutants (penta and PAHs) and on
secondary pollutants (oil, suspended solids, metals, COD,
dioxins, etc.)
The results of the SITE project demonstrated the ability
of the fixed-film, aerobic bioreactor to remove pentachloro-
phenol. At the flow selected as optimum for the system, 5
gpm, removal of 95+% was achieved and an effluent with
about 1 mg/L of pentachlorophenol was attainable. At lower
flow rates, 1 gpm and 3 gpm, pentachlorophenol removal
increased to 99% and final concentrations down to 0.1 mg/L
were achievable.
Polynuclear aromatic hydrocarbons (PAHs) probably were
also removed, either by biodegradation or by adsorption on/in
the bioniass but, unfortunately, the groundwater source itself
contained only low levels of these materials, making it impos-
sible to estimate removal based on differences in analytical
results. Other data from a creosote-contaminated site con-
firmed that PAHs and other phenolics are efficiently removed.
Other studies reported by the vendor (see Appendix D) con-
firm that PAHs are removed, probably by a combination of
biodegradation and adsorption on biosolids.
Secondary pollutants, such as oil, suspended solids, and
even heavy metals, did not appear to interfere with the reac-
tion, at least at the concentrations present in the wastewater
studied during the demonstration. Decreases in Total Organic
Carbon (TOQ and oil and grease indicated that the system
removes other organic species as well. This is supported by
data for other studies in which benzene, toluene, ethyl ben-
zene, and xylene (BTEX) and various chlorinated and oxy-
genated solvents were removed.
Biomonitoring demonstrated that acute toxicity present
in the raw groundwater at the demonstration facility was
essentially totally removed. Coupled with the measured re-
moval of specific chemical species, this suggests that any
form of discharge or reuse would be safe for this wastewater.
Based on the demonstration of the BioTrol fixed-film
aerobic reactor at the MacGillis and Gibbs site, there are
several factors that could be critical to successful, cost effec-
tive operation at other remediation sites. Possibly first among
these is the temperature, both of the feed stream and of the
ambient air. Since it is recognized that biological reactivity is
dependent on temperature, it is beneficial to maintain a reactor
temperature of about 70°F. If groundwater or air temperatures
are significantly lower, this would require the input of more
heat and, consequently, would increase the electrical cost for
heating. The alternative to heating the wastewater would be
enlarging the system to allow for longer retention time. Thus,
the operating temperature of the system becomes a compro-
mise between operating cost (heat required) and capital cost
(system size) with the final decision dependent on costs and
cleanup deadlines. In the same vein, while the capital cost for
the system ($30,000 for 5 gpm and $80,000 for 30 gpm) does
not include the cost for a building enclosure, one might be
necessary, at least for convenient winter operation in certain
parts of the country.
A second critical factor is the concentration of key pollut-
ants that can be tolerated in the feed water and the level
required in the effluent to meet regulatory requirements. In
other laboratory and field studies it had been demonstrated
that the bioreactor is capable of destroying influent PCP
concentrations in the range of 100-200 mg/L in a single pass
with no evidence of toxicity to the system. In addition, partial
recycle could be used to protect the system against toxicity
(by dilution with the treated effluent) and to achieve high
levels of removal or low effluent concentrations—as long as
capacity is available in a specifically sized system. While
successful operation may still be achievable under such condi-
tions, capital cost would increase significantly. Once-through
operation in a properly scaled unit would be more cost-
effective under most circumstances.
A third, perhaps less critical, factor is the extent of the
anticipated remediation. A given volume of feedwater, con-
taining a given concentration of pentachlorophenol or other
contaminants, can be equally well decontaminated, i.e., to the
same final effluent concentration, in a 5 gpm or a 30 gpm
reactor, but time constraints and availability of feedwater may
dictate which system is the more cost-effective or the more
desirable.
Other factors that could affect the utility of the system for
removal of PCP or other contaminants include the presence of
other biodegradable organics and oil, suspended solids, and
heavy metals in the feedwater. While the levels of such
contamination encountered in the demonstration project had
no apparent adverse effect, the character of aerobic biological
treatment is such that nutrient requirements may be affected
and interference may be anticipated at some levels (e.g.,
metals). Clearly such problems are surmountable, as by the
incorporation of an oil/water separator, but overall treatment
cost would increase accordingly. However, it must be recog-
nized that such pretreatment would probably be needed for
almost any aboveground treatment system at some level of
contamination. The acidity or alkalinity of the water would
also play a part, at least by affecting the amount of pH
adjustment needed.
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Section 2
Introduction
The SITE Program
The EPA's Office of Solid Waste and Emergency Re-
sponse (OSWER) and the Office of Research and Develop-
ment (ORD) established the Superfund Innovative Technology
Evaluation (SITE) Program in 1986 to promote the develop-
ment and use of innovative technologies to clean up Super-
fund sites across the country. Now in its fourth year, the SITE
Program is helping to provide the treatment technologies
necessary to implement new federal and state cleanup stan-
dards aimed at permanent remedies, rather tlum quick fixes.
The SITE Program is composed of two major elements: the
Demonstration Program and the Emerging Technologies Pro-
gram. In addition, the Program includes research on analytical
methods.
The major focus has been on the Demonstration Program,
which is designed to provide engineering and cost data on
selected technologies. To date, the demonstration projects
have not involved funding for technology developers. EPA
and the developers participating in the program share the cost
of the demonstration. Developers are responsible for demon-
strating their innovative systems at chosen sites, usually Su-
perfund sites. EPA is responsible for sampling, analyzing, and
evaluating all test results. The result is an assessment of the
technology's performance, reliability, and cost This informa-
tion will be used in conjunction with other data to select the
most appropriate technologies for the cleanup of Superfund
sites.
Developers of innovative technologies apply to the Dem-
onstration Program by responding to EPA's annual solicita-
tion. To qualify for the program, a new technology must have
a pilot or full scale unit and offer some advantage over
existing technologies. Mobile technologies are: of particular
interest to EPA.
Once EPA has accepted a proposal, EPA and the devel-
oper work with the EPA Regional offices and state agencies to
identify a site containing wastes suitable for testing the capa-
bilities of the technology. EPA prepares a detailed sampling
and analysis plan designed to evaluate thorough! y the technol-
ogy and to ensure that the resulting data are reliable. The
duration of a demonstration varies from a few days to several
months, depending on the type of process and the quantity of
waste needed to assess the technology. While it may be
possible to obtain meaningful results in a demonstration last-
ing one week using an incineration process, where contami-
nants are destroyed in a matter of seconds, this is not the case
for a biological treatment process such as the BioTrol process
where contaminant variability, system acclimation, and sys-
tem stability must be examined over an extended period of
time. In order to evaluate such parameters, it was determined
that a minimum of six weeks of operation, at three different
flow rates, was necessary. After the completion of a technol-
ogy demonstration, EPA prepares two reports which are ex-
plained in more detail below. Ultimately, the Demonstration
Program leads to an analysis of the technology's overall
applicability to Superfund problems.
The second principal element of the SITE Program is the
Emerging Technologies Program, which fosters the further
investigation and development of treatment technologies that
are still at the laboratory scale. Successful validation of these
technologies could lead to the development of systems ready
for field demonstration. A third component of the SITE Pro-
gram, the Measurement and Monitoring Technologies Pro-
gram, provides assistance in the development and
demonstration of innovative technologies to better character-
ize Superfund sites. In this case, EPA had the good fortune to
be able to evaluate such a methodology in conjunction with a
demonstration project, as will be described briefly later in this
report.
SITE Program Reports
The results of the SITE Demonstration Program are in-
corporated in two basic documents, the Technology Evalua-
tion Report and the Applications Analysis Report. The former
provides a comprehensive description of the demonstration
and its results. The anticipated audience will be engineers
responsible for detailed evaluation of the technology relative
to other specific sites and waste situations. These technical
evaluators will want to understand thoroughly the perfor-
mance of the technology during the demonstration, and the
advantages, risks, and costs of the technology for the given
application.
The Applications Analysis Report is directed to decision-
makers responsible for selecting and implementing specific
remedial actions. This report provides sufficient information
to determine if the technology merits further consideration as
an option in cleaning up specific sites. If the candidate tech-
nology described in the Applications Analysis appears to meet
the needs of the site engineers, more thorough analysis of the
technology based on the Technology Evaluation Report and
information from remedial investigations for the specific site
will be made. In summary, the Applications Analysis will
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assist in determining whether the specific technology should
be considered further as an option for a particular cleanup
situation.
Purpose of the Applications Analysis Report
Each SITE demonstration will evaluate the performance
of a technology while treating the particular waste found at the
demonstration site. Additional data from other projects also
will be presented where available.
Usually the waste at other sites being considered for
remediation will differ in some way from the waste tested.
Waste characteristic differences could affect waste treatability
and use of the demonstration technology at other sites. Thus,
successful demonstration of a technology at one site does not
assure that a technology will work equally well at other sites.
The operating range over which the technology performs
satisfactorily can only be made by examining a broad range of
wastes and sites. To a limited extent, this report provides an
indication of the applicability of the BATS by examining not
only the demonstration test data but also data available from
other field applications of the technology.
To enable and encourage the general use of demonstrated
technologies, EPA will evaluate the probable applicability of
each technology to sites and wastes in addition to those tested,
and will study the technology's likely costs in these applica-
tions. The results of these analyses will be summarized and
distributed to potentially interested parties through the Appli-
cations Analysis Report.
Key Contacts
For more information on the demonstration of the BioTrol
Aqueous Treatment System for contaminated groundwater,
please contact:
1. Vendor concerning the process:
BioTrol, Inc.
11 PeaveyRoad
Chaska,MN55318
612-448-2515
Dennis D. Chilcote, Vice-president, Engineering
. Thomas Chresand, Development Engineer
2. EPA Project Manager concerning the SITE Demon-
stration:
Mary K. Stinson
U.S. EPA - ORD
Technical Support Branch (MS-104)
2890 Woodbridge Avenue
Edison, NJ 08837-3679
908-321-6683
3. State contact concerning the MacGillis and Gibbs
site:
Mark Lahtinen
Minnesota Pollution Control Agency
Site Response Section
Groundwater and Soil Waste Division
520 Lafayette Road
St. Paul, MN 55155
612-296-7775
4. EPA Regional contact concerning the MacGillis and
Gibbs site:
Darryl Owens
U.S. EPA, Region V
230 South Dearborn Street
Chicago, IL 60604
- 312-886-7089
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Section 3
Technology Applications Analysis
Introduction
This section of the report addresses the potential applica-
bility of the BioTrol Aqueous Treatment System (BATS) to
various other wastewaters and Superfund site situations where
pentachlorophenol is the pollutant of primary interest. Sup-
porting information provided by the vendor, BioTrol, Inc.,
also is referred to as a basis for considering the BATS for
other biodegradable wastes. The demonstration at the MacGiUis
and Gibbs site provides the most extensive data base available
to-date and serves as a foundation for conclusions on the
effectiveness and the applicability to other cleanups. The data
base is expanded somewhat by information concerning other
tests that has been provided by the vendor.
The following subsections summarize observations and
conclusions drawn from the current study und supporting
information. Included are factors such as other applicable
wastewaters, site characteristics and constraints, applicability
of state and federal environmental regulatioms, unique han-
dling requirements, and personnel factors. Additional infor-
mation on the BioTrol technology, including a process
description, vendor claims, a summary of the Demonstration
Test Results and Case Studies of other investigations are
provided in the Appendices.
Conclusions
Based on the results of the demonstration test program at
the MacGillis and Gibbs site and other information, the
vendor's key claims are substantiated. The process can exten-
sively degrade pentachlorophenol. Pentachloiophenol levels
of well under 1 mg/L are achievable, at least at reduced
throughput rates, while percent removals of ait least 95% are
achievable even at the highest flow rate tested, 5 gpm. It
appears that conversion to inorganics (mineralization), carbon
dioxide, water, and chloride ion, rather than to other, interme-
diate organics occurs, but the data on chloride production and
TOC removal are not sufficiently precise to verify this point.
A second claim, that polynuclear aromatic hydrocarbons
are removed, could not be confirmed due to low levels of
PAHs in the incoming grpundwater studied in the SITE test
program and relatively high detection limits in the GC/MS
procedure used to measure the PCP. The concentrations of the
individual PAHs in the effluent were, with one exception,
below detection limits (10-100 \iglL). Other investigations of
PAH-contaminated waters using the BATS have demonstrated
successful removal of PAHs, as noted in Appendix D.
On the basis of acute biomonitoring tests, the BATS
process is capable of converting wastewaters that are toxic (to
certain species, at least) to a non-toxic effluent that should be
suitable for discharge, reuse, or further treatment at a POTW.
The operating costs for the process are estimated on the
basis of the 5 gpm mobile pilot plant and other data available
from BioTrol at between $3.45 and $2.43/1000 gallons for 5
gpm and 30 gpm systems, respectively. Depending on how a
system is used, total operating plus capital cost could be as
low as $2.94/1000 gallons.
The process provides a rapid, compact means of detoxify-
ing and decontaminating wood preserving wastewaters, even
when significant quantities (~50 mg/L) of dispersed oil are
present The BATS has also proven to be effective on other
wastewaters containing a wide range of contaminants includ-
ing the benzene, toluene, ethyl benzene, xylene (BTEX) mix-
ture resulting from gasoline contamination, where >99%
removal of benzene was achieved; a solvent mixture contain-
ing methyl ethyl ketone, cyclohexanone, and tetrahydrofuran
where >99% removal was also achieved even at an influent
COD concentration of 3100 mg/L; and total phenolics from a
creosote waste with a high COD (-1500 mg/L) loading where
phenolics removal was >99%.
The system is simple to operate and requires a minimum
of operator attention or maintenance once the bacterial popu-
lation has been established.
f '""
Discussion of Conclusions
The SITE Program demonstration at the MacGillis and
Gibbs Company facility in New Brighton, MN clearly indi-
cated that at the maximum tested flow rate of 5 gpm the
mobile unit was capable of destroying 95+% of the PCP.
Operation during the demonstration at lower flow rates, i.e., at
longer retention times, demonstrated that even higher PCP
removal levels could be achieved along with final PCP con-
centrations much below 1 mg/L. Thus, depending on the
nature of the contaminated water and the effluent quality
limits imposed, a BATS could be operated successfully.
Pentachlorophenol Removal
The concentration in the available groundwater (<45
mg/L) precluded evaluation of the system's capability at
higher PCP concentrations. However, other work by BioTrol
using wastewater containing in the range of 100 mg/L PCP
-------
demonstrated that the technology was effective (>90% re-
moval, effluent PCP concentration of ~<1 mg/L) at higher
influent concentrations. Based on other studies, BioTrol has
reason to believe that PCP concentrations even higher than
100 mg/L can be tolerated and degraded without adversely
affecting the viability of the bioreaction. It is recognized that
some level of PCP may be reached where a wastewater would
be toxic to the biological growth. At such levels dilution (with
fresh water or with recycled effluent) could be used to de-
crease the "apparent" concentration and still allow use of the
BioTrol technology, albeit at a decreased flow rate.
Mineralization of Pentachlorophenol
Analyses of influent and effluent for chloride and TOC
were carried out in an effort to confirm that the removal of
PCP occurred by total degradation to water, carbon dioxide,
and chloride ions rather than to intermediate, partially chlori-
nated products that simply were not detected by the analytical
protocol. While the changes in both chloride and in TOC were
consistent with total degradation (mineralization) of the PCP,
the changes in both parameters exceeded the expected values.
In the case of the chloride, it is suggested that other.chlori-
nated species may account for the high value. Similarly,
degradation of other organics, including oil and grease and
other organic species not detected by the GC/MS methodol-
ogy, may explain the TOC results.
Polynuclear Aromatic Hydrocarbon Removal
While the vendor, BioTrol, claimed thatpolynuclear aro-
matic hydrocarbons (PAHs) such as those expected from
creosote contamination of the soil and groundwater were also
destroyed by the bacteria, constraints in the analytical proce-
dures make it impossible to validate this claim and it can only
be concluded that only low concentrations (< detection limits)
of any polynuclear aromatic hydrocarbons are present in the
effluent.
In a pilot scale study at another wood preserving site,
>80% removal of PAHs was demonstrated. These results also
indicated that both biodegradation and adsorption on biosolids
contributed to PAH removal from the aqueous waste stream.
Operational Reliability I Stability
The system proved to be quite stable and required a
minimum of attention over the course of the six weeks of
study. Other than some attention to a leaking pump, routine
checking of pH, and preparation of nutrient solutions, there"
was little need for an operator. Certainly, with a large reser-
voir of relatively constant feed water, such as a contaminated
aquifer, the attention required would be minimal. In such
instances it would be desirable to incorporate some means of
on-line monitoring to assure that out-of-compliance effluent
is recycled rather than discharged when no operator is present.
At least some portion of the observed variability in results
probably is attributable to sampling and analytical variations.
Costs
Cost data was developed for the 5 gpm pilot plant unit on
the basis of the experience at the MacGillis and Gibbs site and
other studies by BioTrol with the larger, 30 gpm unit. Other
than some savings achievable by buying nutrients in bulk, the
major factors in operating cost are utilities to provide heat and
the labor to oversee the operation; it is expected that the labor
cost for other biological systems such as activated sludge
would be even higher.
Applicable Wastes
While this study of the BioTrol Aqueous Treatment Sys-
tem was limited to a single wastewater, the groundwater
available at the MacGillis and Gibbs site, the results of the
study along with other results provided by the vendor suggest
that the technology would have wide applicability to other
contaminated groundwaters and process waters. The design of
the system is such that elevated concentrations of contami-
nants in the incoming stream do not affect operation, although
they can be a factor in determining the throughput rate achiev-
able at a particular installation and the nutrient cost contribu-
tion to operation. In other words, if a source of
PCP-contaminated water contains significantly higher levels
of PCP, the safe approach may be to dilute the stream, either
with clean water or with effluent, at least until acclimation can
be demonstrated. Based on other results provided by BioTrol,
the system is well able to withstand and degrade wastewaters
containing as much as 100 mg/L of PCP and probably more
on a once-through basis. COD concentrations of up to 3000
mg/L (from BTEX and oxygenated solvents) have been suc-
cessfully treated in a single pass by the BATS using only
indigenous microorganisms.
Temperature, dissolved oxygen, and pH of an incoming
wastewater could affect the biological reaction, except that
the system incorporates means for bringing these parameters
into line with specifications. The experience at MacGillis and
Gibbs did not indicate nor suggest a particular sensitivity to
any of these factors. While reduced temperature would be
expected to decrease the degradation rate in any biological
treatment system, the BATS is equipped with a heater and a
heat exchanger to maximize the utilization of energy intro-
duced to heat a cold influent. Based on engineering calcula-
tions by BioTrol, the heat losses in the system are equivalent
to only a few degrees.
One other factor that was given careful consideration at
the outset of the demonstration was the question of oil in the
influent. During the demonstration, the system was operated
with a water source containing approximately 50 mg/L of oil
with no apparent adverse effect; in fact, the oil was signifi-
cantly reduced in the effluent, either by adsorption or by
degradation. If necessary, an oil/water separator could be
incorporated in the process train, which should reduce the oil
and grease (O/G) level to well below that tested in this
demonstration.
-------
Other pollutants in the incoming water, such as metals, do
not appear to adversely affect the reaction efficiency, at least
at the levels encountered at the MacGillis and Gibbs site.
There is little reason to suspect that the BioTrol process would
be more (or less) sensitive to metals than any other biological
system.
The proven track record of biological treatment for many
wastewaters contaminated with organics suggests the applica-
bility of this technology to other wastes. The BioTrol process,
requiring minimal reactor volume and providing high removal
rates at relatively high influent concentrations of specific
contaminants by virtue of the plug flow design, should be
well-suited to other wastes. The system's use of an inoculum
of a waste-specific bacterium for particularly nscalcitrant pol-
lutants such as PCP suggests that the process could be "cus-
tomized" to other constituents where indigenous
microorganisms are not present
Site Characteristics
In the demonstration program a mobile pilot plant system
was used that required only a level base (ideally a concrete
pad); potable water and power were supplied by the site
operator. If necessary, the small amount of potable water
needed could be trucked in and power could be jjrovided by an
on-site generator. In any case where groundwater was being
brought up by pump from a well for treatment, power for that
pump would have to be provided. If the water being treated
were surface water (e.g., a storage lagoon), this might not be
necessary. In either case, placement of the system close to the
water source would reduce pumping requirements.
Geography could play a small role in the eitfectiveness of
the BioTrol system, as it would with any biological treatment.
Significantly colder ambient temperatures can reduce biologi-
cal reaction rates. As noted earlier, the BioTrol system is
equipped with a heat exchanger and heater and low ambient
temperatures can be traded-off for a [small] increase in heat
input, since most heat can be reclaimed.
With the demonstrated ability of the vendor's system to
reduce pentachlorophenol levels to well below 1 mg/L, accep-
tance of the effluent by POTWs should not be a problem in
most communities. Even direct discharge to receiving waters
may be defensible in light of the analytical and foiomonitoring
results obtained at the MacGillis and Gibbs site. Reuse of the
treated wastewater should also be attractive smce the only
additions to the water would be small amounts of nutrients
and salt. These conclusions are based on the MacGillis and
Gibbs groundwater and would have to be reconjfirmed for any
other wastewater.
Environmental Regulation Requirements
Anticipating that the BioTrol system would be used on
groundwater at a contaminated site, a first concern would be
local well-drilling requirements. Depending on the size of
these wells, their capacity, and the capacity of the treatment
system being installed, storage tanks may be desirable as a
reservoir and to provide needed equalization. Such tanks may
need regulatory attention (permits, materials, eft;.), depending
on their size and whether they are placed above or below
ground.
It is probable that the treated effluent from any similar
site would be suitable for direct discharge or discharge to a
POTW as "pretreated". At most, a NPDES permit (or state
equivalent) should be required. However, under the Resource
Conservation and Recovery Act of 1976 (RCRA) and the
Hazardous and Solid Waste Amendments of 1984 (HSWA),
there is some question as to whether the effluent, as a residual
from treatment of a hazardous waste, would itself be consid-
ered hazardous, in spite of its apparent nonhazardous charac-
ter.
Under the Comprehensive Environmental Response, Com-
pensation, and Liability Act of 1980 (CERCLA) and the
Superfund Amendments and Reauthorization Act of 1986
(SARA), EPA is responsible for determining the methods and
criteria for the extent of removal. The utility and cost effec-
tiveness of the BioTrol system would, to an extent, be depen-
dent on the final level deemed appropriate and necessary at a
particular site by EPA. However, since the use of remedial
actions by treatment that "...permanently and significantly
reduces the volume, toxicity, or mobility of hazardous sub-
stances" is strongly recommended (Section 121 of SARA),
the BioTrol system would appear to be an attractive remedy
for a site contaminated with wood preserving chemicals.
SARA also added a new criterion for assessing cleanups
that includes consideration of potential contamination of the
ambient air. This is in addition to general criteria requiring
that remedies be protective of human health and the environ-
ment. This demonstration has established that pentachloro-
phenol is not emitted to the ambient air. However, from a
worker and environment safety point of view, it still may be
desirable to incorporate an air treatment system (e.g., carbon)
to assure that the escape of the more volatile PAHs such as
naphthalene and 2-methyl naphthalene is minimized, even
though the observed level of naphthalene at the MacGillis and
Gibbs site (=<1 mg/L) is well below the OSHA Permissible
Exposure Limit of 10 mg/L. And, if such a control system is
installed to collect the emissions from the reactor, a state or
local permit to construct and operate an air emissions control
unit may be required.
Finally, the very limited data on dioxins/furans and their
frequent occurrence in conjunction with chlorocarbon prod-
ucts suggest that it would be prudent to evaluate whether the
small volume of sludge produced from the BioTrol system has
to be considered to be dioxin-contaminated and managed in
accordance with RCRA, thereby increasing total cost some-
what. Concurrently, any carbon used in an air treatment
system or for effluent polishing at a particular site would also
have to be tested to determine whether it is contaminated with
dioxins, in which case special handling would also be neces-
sary.
Materials Handling Requirements
If the BioTrol system is to be used to treat groundwater,
the first need is a well drilling rig to provide the well(s) from
which the feedwater is to be obtained. Once the wells are
-------
drilled and developed, each must be equipped with a pump to
draw up the necessary feed water. Local well drilling require-
ments would have to be taken into consideration.
If the vendor's system is provided with relatively clean
ground- or process water, little special handling is needed
other than pH and temperature adjustment and these needs are
incorporated in the system. The demonstration has also shown
that a reasonably high level of oil (~50 mg/L) has no effect.
The vendor indicates that significantly higher levels of oil can
be tolerated. However, in the event that even higher levels are
present in a source water, a simple oil/water separator should
suffice to reduce the level to an acceptable level (see Appen-
dix D-l). Similarly, a clarifier could be added to remove high
levels of suspended solids.
Operationally, the only problem encountered was the
apparent backmixing through the underflow weirs separating
each chamber. This seemed to have no effect on the effluent
quality, and may only influence decisions as to sampling
points in future installations.
While groundwater tends to be reasonably consistent
over time, such may not be the case with other wastewaters. In
certain cases it may be desirable to install a storage tank or
even a lagoon for equalization and to avoid shock loading that
could, conceivably, adversely affect biological activity. De-
pending on their design, the regulatory impacts of such tanks
or basins could need to be considered.
If a large source of contamination were being treated, it
would be cost-effective to purchase nutrients and caustic in
bulk. In that event storage facilities would be required.
Personnel Issues
Even during acclimation, the system requires little atten-
tion. Nutrient addition and pH adjustment are carried out
automatically. Consequently, there is little labor requirement
other than to assure that all pumps are operating, nutrient and
caustic reservoirs are filled, and that the final effluent is
meeting discharge requirements. Some additional time would
be required if oil/water separation, suspended solids removal,
or effluent polishing is required at a particular installation.
Consideration should be given to equipping operators work-
ing on or near the system with skin and respirator protection if
exposure could occur by contact with liquid or mist when
opening the bioreactor, or to air emissions stripped from the
system.
Testing Issues
At this time, the only approved method for pentachloro-
phenol analysis during monitoring is the GC/MS method for
semivolatiles. This is a costly and time-consuming procedure
not well suited to on-line use for process control or effluent
monitoring. BioTrol has developed a high pressure liquid
chromatographic (HPLC) procedure which is much faster and
may be acceptable to site management and regulatory person-
nel for routine use. A comparison of the BioTrol HPLC
procedure and the EPA method conducted as part of the QA
program for the demonstration indicated that the BioTrol
method is accurate for samples containing PCP concentra-
tions of 1 mg/L or higher.
EPA's Environmental Monitoring Systems Laboratory
(EMSL) also is evaluating an alternate immunoassay tech-
nique that would be well suited to field use and would be very
economical. At this time, whether the field test provides
comparable results has not been validated and widescale
application is certainly several years away. As with any
analytical procedure, it also would be necessary to establish
that the waste matrix at a particular site does not interfere with
the quality of results.
-------
Section 4
Economic Analysis
Introduction
The primary purpose of this economic analysis is to
estimate costs (not including profit) for commercial-scale
remediation using the BioTrol Aqueous Treatment System
(BATS). With realistic costs and a knowledge of the bases for
their determination, it should be possible to estimate the
economics for operating similar-sized systems at other sites
utilizing various scale-up cost formulas available in the litera-
ture such as the "six-tenths rule".
This economic analysis is based on assumptions and
costs provided by BioTrol and on results and experiences
from this SITE demonstration developed over two weeks of
operation at 5 gpm. It is assumed that the performance of
commercial-scale equipment will be the same as that demon-
strated here for a pilot-scale 5 gpm mobile; unit with an
influent containing approximately 45 ppm of penta and achiev-
ing 95% removal. Certain actual or potential costs were
omitted because site-specific engineering aspects beyond the
scope of this SITE project would be required. Certain other
functions were assumed to be the obligation of ithe responsible
parties or site owner and also were not included in the
estimates. Cost figures provided here are "order-of-magni-
tude" estimates, generally +50%/-30%, and are representative
of charges typically assessed to the client by the vendor
exclusive of profit.
The reader is also urged to obtain and review the Applica-
tions Analysis Report for the companion study, in which the
BATS is used to treat process water from a soil washer.
Conclusions
• The cost to treat groundwater using the BATS in three
different configurations is given below:
Configuration $11000 gal.
5 gpm leased mobile unit 14.56
5 gpm purchased fixed unit 4.61
30 gpm purchased fixed unit 2.94
• For the 5 gpm leased mobile unit, the largest cost compo-
nent is the equipment lease rate (76%), followed by utili-
ties (11%), and labor (10%). For the 5 gpm purchased
fixed unit, the largest cost component is utilities (37%)
followed by labor (32%), and capital equipment (25%).
On a $/1000 gal basis, capital equipment costs for the fixed
unit appear to be an order of magnitude less than for the
mobile unit. It should be remembered, however, that an
initial investment of $30,000 is required to purchase the
fixed unit.
Buying a 5 gpm treatment system would be economical if
it is to be used for at least 12 months.
• For fixed units there are economic advantages due to scale,
especially for labor. On a $/1000 gal basis, utilities are the
largest cost component followed by labor and equipment
costs. However, there is a point of diminishing returns. A
six-fold increase in size resulted in a 35% reduction in
costs.
• In all instances, influent heating accounted for a dispropor-
tionate share of operating costs (10-50%). Influent heating
may not always be necessary. And even when it is neces-
sary, it will be used only during the colder months.
• In no instance did consumables and supplies account for
any more than 10% of total cleanup costs.
Issues and Assumptions
This section summarizes the major issues and assump-
tions used to evaluate the cost of BioTrol's Aqueous Treat-
ment System. Li general, assumptions are based on information
provided by BioTrol. Certain assumptions were made to ac-
count for variable site and waste parameters and will, un-
doubtedly, have to be refined to reflect site specific conditions.
Waste Volumes and Site Size
The volume of groundwater to be treated at the MacGillis
and Gibbs Superfund site has not yet been determined. Be-
cause cleanup objectives have not yet been established, it is
not clear as to exactly how BioTrol will propose to remediate
the site. Pumping and treating the groundwater already there
may be sufficient to stop the plume from spreading, but
insufficient to reduce the contaminant concentration in new
groundwater that will seep in. To accomplish this goal, a
larger volume of groundwater will have to be treated for a
much longer period of time. To bypass this question, costs are
given per 1000 gal of groundwater treated.
System Design and Performance Factors
Figure.C-3 in Appendix C shows a simplified flowsheet
of BioTrol's pilot-scale Aqueous Treatment System. It was
-------
assumed that a commercial-scale unit would be similar in
design and performance to that demonstrated under the SITE
program.
For the purposes of this analysis, it was not necessary to
assume a particular contaminant concentration. It was as-
sumed that the performance of a commercial-scale unit would
be the same as that demonstrated here and that this level of
reduction would be sufficient so as not to require any further
treatment
The cost estimates do not include provisions for oil/water
separation, suspended solids removal, exhaust air collection
and/or treatment, or effluent polishing since these items are
completely site and waste specific.
System Operating Requirements
Although the volume of the reactor is designed to give a
certain level of reduction for a certain residence time at its
design flow rate, it is entirely possible to operate the unit at a
lower flowrate and increase the residence time to increase
contaminant reduction. Examination of such flowrate varia-
tion was attempted in this study but, unfortunately, influent
contaminant concentrations varied too much to draw any
definitive conclusions. Decreased flowrate would increase the
cleanup time and the associated costs. For this analysis, all
units were assumed to be operated at their design flowrates
and that this was sufficient to achieve the desired reduction.
It was assumed that the BATS would operate 24 hours
per day, 7 days per week. One lead operator would be required
approximately 10 hr/week to attend to the unit
Utilization Rates and Maintenance Schedules
Costs per 1000 gal have not assumed any downtime.
Since this is a continuously operating, steady-state system
with very few moving parts, utilization rates should be quite
high. Two weeks for mobilization and training and one week
for demobilization were assumed.
Financial Assumptions
For the purpose of this analysis, capital equipment costs
were amortized over a 10 year period with no salvage value.
Interest rates, time-value of money, etc. were not taken into
account
Basis for Economic Analysis
In order to compare the cost-effectiveness of technolo-
gies in the SITE program, EPA breaks down costs into 12
categories shown in Table 1 using the assumptions already
described. The assumptions used for each cost factor are
described in more detail below.
Site Preparation Costs
The amount of preliminary preparation will depend on
the site and is assumed to be performed by the .responsible
party (or site owner). Site preparation 'responsibilities include
site design and layout, surveys and site logistics, legal searches,
access rights and roads, and preparations for support facilities,
decontamination facilities, utility connections, and auxiliary
buildings. Since these costs are site-specific, they are not
included.
Additionally, well drilling and preparation are assumed
to be performed by the responsible party (or site owner) and
are also highly site-specific. Hence, these costs are also not
included.
Permitting and Regulatory Costs
Permitting and regulatory costs are generally the obliga-
tion of the responsible party (or site owner). These costs may
include actual permit costs, system health/safety monitoring,
and analytical protocols. Permitting and regulatory costs can
vary greatly because they are very site- and waste-specific. No
permitting costs are included in this analysis; however, de-
pending on the treatment site, this may be a significant factor
since permitting can be a very expensive and time-consuming
activity.
Equipment Costs
Capital equipment costs were provided by BioTrol, Inc.,
for three configurations:
a. A 5 gpm mobile unit that would be leased for $24007
month. This would be suitable for short term cleanups.
b. A 5 gpm skid mounted unit which could be purchased
for $30,000. This could be used for long term treatment
of a relatively low flow stream such as leachate from a
pond.
c. A 30 gpm skid mounted unit which could be purchased
for $80,000. This could be used to treat a larger aquifer.
The 5 gpm and 30 gpm purchased units were amortized
over a 10 year period with no salvage value assumed at the
end. This works out to $250/mo for the 5 gpm installation and
$667/mo for the 30 gpm installation.
To determine costs per 1000 gal of water treated, these
monthly amortized costs were divided by the respective
flowrates expressed in gal/mo, (assuming 24 hr/day and 30
days/mo). The reader is cautioned to use these numbers with
great care due to the amortization assumptions just made.
Capital costs per 1000 gal may appear to be the lowest for the
30 gpm unit but an $80,000 investment is required up front.
For short cleanup times this is clearly uneconomical. Like-
wise, for the 5 gpm skid mounted unit, a cleanup time of more
than 12 months would make this purchase option more eco-
nomically attractive than leasing a unit.
Startup
As the name implies, the 5 gpm mobile unit is designed to
be moved from site to site. Transportation costs are only
charged to the client for one direction of travel and are usually
included with mobilization rather than demobilization. Trans-
10
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Table 1.
Estimated Costa forUacGillls and Gibbs Site
Cost Category
Sgpm Mobile
$/1000gal %
Sgpm Fixed
$/1000gat
Total
14.56
99
4.61
100
30 gpm Fixed
$/1000gal
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Site Preparation
Permitting and Regulatory Requirements
Capital Equipment (amortized over 10 years)
Startup
Labor
Salary ,
Consumables & Supplies
Nutrient
Caustic
Utilities
Electricity
Heat
Effluent Treatment & Disposal
Residuals/Waste Shipping & Handling
Analytical Services
Facility Repair, Replacement & Modification
Demobilization
N/A
N/A
11.11
N/A
1.49
0.042
0.24
0.216
1.46
N/A
N/A
N/A
N/A
N/A
N/A
N/A
76
N/A
10
2
1
10
N/A
N/A
N/A
N/A
N/A
N/A
N/A
1.16
N/A
1.49
0.042
0.24
0.216
1.46
N/A
N/A
N/A
N/A
N/A
N/A
N/A
25
N/A
32
1
5
5
32
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.51
N/A
0.50
0.017
0.24
0.216
1.46
N/A
N/A
N/A
N/A
N/A
N/A
N/A
17
N/A
17
1
8
7
50
N/A
N/A
N/A -
N/A
N/A
2.94
100
portation costs are variable and dependent on site location as
well as on applicable size/weight load permits, which vary
from state to state. The total cost will depend on how many
state lines are crossed. For purchased units, transportation
costs are borne by the buyer.
The amount of assembly required for the mobile unit is
minimal. For the purchased units, assembly is a labor inten-
sive operation consisting of unloading equipment from trucks
and trailers used for transportation, as well as actual assembly.
Mobilization, training, and acclimation are estimated to take 1
person working a 40 hr week about 2 weeks and this time
should be included in the total time on site.
Depending on the site, local authorities may impose
specific guidelines for health and safety monitoring programs.
The stringency and frequency of monitoring required may
have a significant impact on project costs.
Labor
Once the system is acclimated and operating at steady
state, very little additional labor is involved. It is estimated
that a Project Engineer at $35/hr would spend 1 hr/week and a
Lead Operator at $25/hr would spend 10 hr/week on the 30
gpm unit and 5 hr/week on the 5 gpm unit for maintenance
and operation. These numbers include salary., benefits, and
administration/overhead costs but exclude profit. BioTrol cal-
culates the labor to be $1.49/1000 gal for the 5 gpm units and
$0.50/1000 gal for the 30 gpm unit No provisions for per
diem or car rental have been included in these figures.
Consumables and Supplies
Caustic usage would be determined by the pH and alka-
linity of the incoming water to be treated. For purposes of this
cost estimate, usage was assumed to be the same as that
demonstrated under this SITE project (.09 gal of 50% solution
per 1000 gal of water treated). More or less caustic may be
required at another site; however, caustic use should remain
essentially constant throughout the treatment of a specific
waste. For a commercial scale cleanup, a cost of $2.60/gal of
50% solution was assumed. Thus, the cost would be $0.24/
1000 gal of water.
Nutrients in the form of urea and trisodium phosphate
dissolved in water in a 2:1 weight ratio are usually added
regardless of system size. At the MacGillis and Gibbs demon-
stration site, a nutrient mixture consisting of 5 Ib urea plus 2.5
Ib of trisodium phosphate dissolved in 50 gallons of water was
added at a rate of 2.5 ml/gallon of wastewater. For the 5 gpm
units, the prices given reflect purchase of the ingredients at a
local fertilizer supplier; for the larger system some economy
of scale has been factored in on the assumption that the two
materials would be purchased in bulk. The cost for storage
facilities should be included in site preparation.
Two other items that should be considered but were not
included are health and safety gear, and maintenance supplies
(spare parts, oils, grease and other lubricants, etc.). Since the,
manpower requirements for both systems are the same, the
cost for health and safety gear will be minimal (about $500).
The cost of maintenance supplies can be assumed not to
exceed 2% of the capital costs on a yearly basis.
11
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Utilities
The total electrical demand for both units is estimated to
be about 10 HP. This includes the pump used to deliver the
groundwater to the BATS, a second pump to discharge the
water against an assumed head of 50 ft of water within the
BATS, and an air sparger blower. Electricity required for the
air sparger blower motor will decrease somewhat for the 30
gpm unit since the reactor chambers would be 8 ft deep rather
than the nominal 4 ft used in the 5 gpm unit, providing more
efficient "capture" of the dispersed air. However, there would
also be a somewhat higher head pressure. The vendor's calcu-
lations indicate the benefit will be minimal and the same value
has been used for both size units. It does not include electric-
ity that may be required to heat the influent. Electricity was
assumed to cost $0.06/kw-hr.
The amount of heat required at a particular site would be
dependent on the incoming water temperature, the ambient
temperature and resulting heat loss, as well as the exothermic-
ity of the reactions for a particular wastewater. Practically, the
heat exchanger can transfer or return enough heat from the
effluent so that the difference is only about 3T. Coupled with
an assumed 2°F loss to the atmosphere, the actual difference
between influent and effluent will only be about 5°F and is
essentially independent of the temperature of the water source
except during the startup. At the MacGillis and Gibbs site
during July to September, the average groundwater tempra-
ture was 55°F. (13°C) and the heater was not used. A differ-
ence of 5°F between influent and effluent temperatures and
electricity at $0.06/kw-hr were assumed.
Effluent Treatment and Disposal
The effluent from the BATS can be handled several
ways. It can be injected back into the ground to effectively
"flush out" contaminant from the soil. In this case, the effluent
contaminant concentration is not a critical parameter. If the
effluent is clean enough to meet regulatory standards, it may
be discharged to a POTW. If the effluent is not clean enough
to meet regulatory standards, it may be recycled and mixed
with the influent for further treatment. This will obviously
extend the required cleanup time and the associated costs.
There obviously are too many variations for each one of
these scenarios to be considered here. For simplicity, it will be
assumed that the effluent is clean enough to meet regulatory
standards and hence can be directly discharged to a POTW
without further treatment.
Residuals/Waste Shipping, Handling and
Transport Costs
Waste disposal costs, including storage, transportation,
and treatment costs, are assumed to be the obligation of the
responsible party (or site owner). It is assumed that residual or
solid wastes generated from this process would consist only of
contaminated health and safety gear, used filters, spent acti-
vated carbon, etc. Landfilling is the anticipated disposal method
for this material at an estimated cost of $100/drum.
Analytical Costs
No analytical costs during operations are included in this
cost estimate. Standard operating procedures for BioTrol do
not require planned sampling and analytical activities. Peri-
odic spot checks may be executed at BioTrol's discretion to
verify that equipment is performing properly and that cleanup
criteria are being met, but costs incurred from these actions
are not assessed to the client The client may elect, or may be
required by local authorities, to initiate a sampling and ana-
lytical program at their own expense.
Facility Modification, Repair and Replacement
Costs
As stated earlier, site preparation costs are assumed to be
borne by the responsible party (or site owner). Likewise, any
modification, repair, or replacement to the site was assumed
to be done by the responsible party (or site owner).
Demobilization Costs
It is estimated that demobilization would take about 1
week. Site cleanup and restoration is limited to the removal of
all equipment and facilities from the site. Grading or
recompaction requirements of the soil will vary depending on
the future use of the site and is assumed to be the obligation of
the responsible party or site owner.
Results
Table 1 shows several interesting trends regarding mobile
and fixed units as well as the size of fixed units.
For the 5 gpm mobile unit, the largest cost component is
the equipment lease rate (76%) followed by utilities (11%),
and labor (10%). Comparing this with the 5 gpm fixed unit,
the largest cost component is utilities (37%), followed by
labor (32%), and capital equipment (25%). The reader is
cautioned to view these relative percentages carefully.
Although capital equipment costs appear to be an order of
magnitude less on a $/1000 gal basis, an initial investment of
$30,000 must be made for the 5 gpm fixed unit Such a capital
outlay can only be justified for long duration or large clean-
ups. The breakeven decision point between a fixed and mobile
unit is 12 months ($30,000 for fixed unit -«- $2,400/mo for
mobile unit). Therefore, even if a 5 gpm fixed unit is not used
for the full 10 year period assumed here, it might be economi-
cal to purchase the equipment if it is to be used for at least 12
months. The decision will be influenced by other financial
considerations, i.e., interest rates, time value of money, cash
flow, etc.
Secondly, influent heating accounts for a disproportion-
ate amount of operating costs. As noted earlier, influent
heating may not be necessary in the majority of cases. Even
when it is required, it will only be used during the coldest
months of the year. Additionally, influent heating was as-
sumed to be done relatively expensively using electricity. A
gas, oil-fired, or solar heat exchanger could accomplish this
12
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much more efficiently. These points should be kept in mind
when comparing total cleanup costs on a $/1000 gal basis.
Differences between the 5 gpni and 30 gpm fixed units
are less dramatic. Utilities are still the largest cost component
(37% for the 5 gpm unit, 57% for the 30 £!pm unit), but
capital equipment and labor costs have a more equal share for
the 30 gpm unit This, in part, is no doubt due to economy of
scale, especially the labor cost component, wtiich is half the
amount of the 5 gpm unit Again, heating accounts for a
disproportionate share of operating costs. In no instance did
consumables and supplies account for any more than 10% of
total cleanup costs.
Comparison of total cleanup costs on a $/1000 gal basis
indicates that there is a point of diminishing returns, as
expected. A six-fold increase in size amounts to about a 35%
reduction in costs.
In all of the above analysis, it should be remembered that
costs for only 4 out of the 12 cost components were consid-
ered. If the additional factors are taken into account, costs
could increase significantly.
13
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-------
Section 5
Bibliography
1. Bishop, J., GAINING ACCEPTANCE,, Hazmat
World, June 1989, p. 37 ffd.
2. Brown, E J., et al, PENTACHLOROPHENOL 12.
DEGRADATION: A PURE BACTERIAL CUL-
TURE AND AN EPILITfflC MICROBIAL CON-
SORTIUM, Applied and Environmental Microbiol-
ogy, July 1986, p. 92-97.
3. Bourquin, A.W., BIOREMEDIATION OF HAZARD- 13.
OUS WASTE, HMC, Sept./Oct. 1989, p. 16 ffd.
4. Dworkin, D. and R.M. Shapot, INNOVATIVE
REMEDIAL TECHNOLOGIES AT A CREOSOTE-
BASED WOOD TREATMENT PLANT, presented at 14.
HAZMAT'88, Nov. 8-11,1988.
5. EPA, BIOLOGICAL TREATMENT OF
CHLOROPHENOLIC WASTES, Final Report,
Project No. 12130 EGK, June 1971.
15.
6. EPA, METHODS FOR CHEMICAL ANALYSIS OF
WATER AND WASTES, U.S. Environmental
Protection Agency, Environmental Monitoring and
Support Laboratory, Cincinnati, OH., EPA-600/4-79- 16.
020. Revised March 1983.
7. EPA, SUPERFUND INNOVATIVE TECHNOLOGY
EVALUATION (SITE) STRATEGY AND PRO- 17.
GRAM PLAN, EPA/540/G-86/001, Dec. 1986.
8. EPA, TEST METHODS FOR EVALUATING
SOLID WASTE, SW-846, U.S. Environmental
Protection Agency, US Government Printing Office,
Washington, DC, Third Edition, Nov. 1986.
18.
9. Finlayson, G., MICROBIAL CLEANUP OF TOXIC
WASTES MAY PROVIDE ALTERNATIVE
SOLUTION, Occupational Health and Safety, Jan.
1990, p. 36,38,40,57. 19.
10. Kennedy, M.S., J. Grammas and W.B. Arbuckle,
PARACHLOROPHENOL DEGRADATION USING
BIOAUGMENTATION, Research J. Water Pollution
Control Federation, 62 #3,227-233 May/Iune 1990. 20.
11. Lee, L.S., et al, INFLUENCE OF SOLENT AND
SORBENT CHARACTERISTICS ON DISTRIBU-
TION OF PENTACHLOROPHENOL IN
OCTANOL-WATER AND SOIL-WA1ER SYS-
TEMS, Environmental Science and Technology,
24,#5,654-661 (1990).
Lee, K.M. and H.D. Stensel, AERATION AND
SUBSTRATE UTILIZATION IN A SPARGED
PACKED-BED BIOFILM REACTOR, J. Water
Pollution Control Federation, 55 #11,1066-1072
(1986).
Loper, J.C., THE FUTURE OF BIOREMEDIATION:
PROSPECTS FOR GENETICALLY ENGINEERED
MICROORGANISMS, HMC, Sept./Oct. 1989, p. 24
ffd.
Mathewson, J.R. and R.B. Jones, COMMERCIAL
MICROORGANISMS, Hazmat World, June 1989 p.
48-51.
Mueller, J.G., PJ. Chapman and P.H. Pritchard,
CREOSOTE-CONTAMINATED SITES—THEIR
POTENTIAL FOR BIOREMEDIATION, Environ-
mental Science and Technology, 23, #10,1197-1201
(1989).
Nicholas, R.B. and D.E. Giamporcaro, NATURE'S
PRESCRIPTION, Hazmat World, June 1989, p. 30
ffd.
PEI Associates, Inc., REMEDIAL ALTERNATIVES
REPORT FOR THE MACGILLIS AND GIBBS CO.
HAZARDOUS WASTE SITE IN NEW BRIGHTON,
MINNESOTA, for Twin City Testing and Engineer-
ing Laboratory Inc., State PMN Contract No. 13726,
Subcontract No. 1-35086, PN 3686, April 1987.
Piotrowski, M.R., BIOREMEDIATION: TESTING
THE WATERS, Civil Engineering, Aug., 1989, p. 51-
53.
Rusten, B., WASTEWATER TREATMENT WITH
AERATED SUBMERGED BIOLOGICAL FILTERS,
J. Water Pollution Control Federation, 56 #5,424-431
(1984).
Saber, D.L. and R.L. Crawford, ISOLATION AND
CHARACTERIZATION OF FLAVOB ACTERIUM
STRAINS THAT DEGRADE PENTACHLORO-
PHENOL, Applied and Environmental Microbiology,
Dec. 1985, p. 1512-1518.
15
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21. Skladany, G J. and K.M. Sullivan, "DECAY
THEORY" BIOLOGICAL TREATMENT FOR
LOW-LEVEL ORGANIC CONTAMINATED
GROUNDWATER AND INDUSTRIAL WASTE,
Superfund '87 Conference (HMCRI), Nov. 17,1987,
Washington, D.C.
22. Stciert, J.G. and RJL Crawford, MICROBIAL
DEGRADATION OF CHLORINATED PHENOLS,
Trends in Biotechnology, 3, #12,1985, p. 300-305.
23. Stinson, M.K., W. Hahn and H.S. Skovronek, SITE
DEMONSTRATION OF BIOLOGICAL TREAT-
MENT OF GROUNDWATER BY BIOTROL, INC.
AT A WOOD PRESERVING SITE IN NEW
BRIGHTON, MN, Presented at 16th Annual EPA
Research Symposium, Cincinnati, OH, April 3-5,
1990.
24. Topp, E., R.L. Crawford, and R.S. Hanson, INFLU-
ENCE OF READILY METABOLIZABLE CARBON
ON PENTACHLOROPHENOL METABOLISM BY
A PENTACHLOROPHENOL-DEGRADING
FLAVOBACTERIUM SPECIES, Applied and
Environmental Microbiology, Oct. 1988, p. 2452-
2459.
25. Torpy, M.F., HP. Stroo, and G. Brubaker, BIOLOGI-
CAL TREATMENT OF HAZARDOUS WASTE,
Pollution Engineering, May 1989, p. 80 ffd.
26. Twin City Testing Corp., REMEDIAL INVESTIGA-
TION REPORT: MACGILLIS AND GIBBS COM-
PANY SITE, NEW BRIGHTON, MINNESOTA,
Document #120-86-414 for Minnesota Pollution
Control Agency, June 25,1986.
27. Valine, S.B., TJ. Chresand and D.D. Chilcote, SOIL
WASHING SYSTEM FOR USE AT WOOD PRE-
SERVING SITES, Proceedings of the 1989 Air and
Waste Management Association/USEPA International
Symposium, p. 257-268, Feb. 20-23,1989, Air and
Waste Management Association, 1989, Pittsburgh,
PA.
28. Wilson, S., THE IMPORTANCE OF BIOREMEDIA-
TION, Pollution Equipment News, Dec. 1989, p. 67
ffd.
16
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Appendix A
Process Description
Introduction
This section of the report presents a concise description
of the process as it was carried out at the MacGillis and Gibbs
site. Predemonstration factors involved in site selection are
presented to assist engineers and scientists in evaluating the
suitability of the process for their own needs at Superfund and
other hazardous waste sites. Results of the demonstration,
including a summary of analytical test results, are presented in
Appendix C.
Brief reference is also made in this Appendix to two
parallel studies that were also carried out in conjunction with
the evaluation of the biological treatment process. These were
the BioTrol soil washing study and the Westinghouse field
immunoassay methodology for pentachlorophenol monitor-
ing. Both of these subjects will be presented fully in indepen-
dent SITE Program reports.
Process Description
Biological treatment has been widely used for many
years in the treatment of industrial and municipal wastewa-
ters, with aerobic treatment being the most widely used tech-
nology. However, as industrial products have l>een developed
to provide resistance to degradation by the environment, it has
often been assumed that these chemicals also would be resis-
tant to conventional biodegradation. Of speciflc concern has
been the resistance of chlorinated organics to biodegradation.
It has now been confirmed that using proper procedures and
with development of suitable biological populations, efficient
biodegradation of many organic chemicals, including chlori-
nated aromatics such as pentachlorophenol, can be achieved.
To provide the most efficient and cost effective treatment
of wastewaters containing such contaminants, BioTrol, Inc.
has developed and applied for a patent for a process called
amended fixed-film aerobic treatment In this technique an
initial biogrowth is developed on an inert support matrix such
as corrugated poly vinyl chloride sheets (Figure; A-l) using an
indigenous bacterial source. The initial bacterial population,
having come from the local soil, has developed some resis-
tance to the toxicity of the local contaminants and has devel-
oped a population distribution which favors the: destruction of
such chemicals. After this bacterial source has! been allowed
to grow and establish itself on the matrix in tide presence of
nutrients and a less toxic wastewater, an inoculum of a bacte-
rium specific to the target chemical, pentachlorophenol in this
case* may be added and further acclimation is allowed to
occur using the subject wastewater in a total recycle mode.
The system is then ready for once-through treatment of the
groundwater.
The design of the BioTrol system allows the development
of the largest concentration or population of bacteria capable
of degrading pentachlorophenol in the first chamber, where
the concentration is highest. As the wastewater flows through
the reactor and the pentachlorophenol concentration dimin-
ishes, other bacteria more suitable to degradation of other
contaminants, but perhaps more sensitive to deactivation by
pentachlorophenol, have the opportunity to grow and con-
sume those contaminants.
The BioTrol system used in this demonstration consists
of a single mobile trailer (20 ft) on which all the vessels,
pumps, etc. for the entire process are installed (Figure A-2). A
level area (ideally a concrete apron) about 50 x 50 ft is needed
to support the trailer and auxiliary facilities. The hydraulic
capacity is about 10 gpm. Contaminated water from any
source is brought to a mixing or conditioning tank where the
pH is automatically adjusted as necessary to just above 7.0 by
metering in a 50% caustic solution. A solution of nitrogen and
phosphorus nutrients (urea plus trisodium phosphate) is also
metered in at a predetermined rate. The mixed water is passed
through a heat exchanger and then through a heater to elevate
the temperature to about 70°F (21°C) before it is introduced
into a 3-cell biological reactor (Figure A-3). As shown in
Figure A-4, influent is introduced into the base of each
chamber by means of an underflow weir. Air is simulta-
neously pumped to the base of each chamber and distributed
by a network of sparger tubes to maintain sufficient dissolved
oxygen (about 5 ppm). The combination of the flow, the air
sparging, and the design of the plastic media are such that
upward and lateral distribution of the water and the air occur
in each chamber. After moving through the three chambers,
the effluent exits at an overflow weir from the third chamber.
While the process is claimed to be relatively insensitive
to suspended solids and dispersed oil and does not incorporate
means of removing these contaminants, the vendor recognizes
and is ready to incorporate oil/water separation or solids
removal as necessary, depending on the wastewater being
treated. In the case of the MacGillis and Gibbs site, no such
pretreatment was deemed necessary.
Similarly, while BioTrol's experience has been that post-
treatments such as suspended solids removal or carbon polish-
17
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Blocks
Cross-stacked
FIguro A-1. Corrugated polyvlnyl chloride media.
ing are not always necessary, EPA made the decision that a
small bag filter and a carbon adsorber would be added to the
effluent line to assure the safety of the discharge to the
Minneapolis Metropolitan POTW. EPA also chose to install a
carbon adsorber on the air exhaust line exiting from the
bioreactor to assure that no hazardous volatile chemicals were
discharged. Analyses were carried out before and after both
carbon adsorbers as part of the demonstration program to
assess the need for such protective devices at future sites.
BioTrol Soil Washing Process
In addition to the Aqueous Treatment System, Biotrol
also has developed a soil washing process that separates large,
relatively uncontaminated sand from more heavily contami-
nated fine material such as clay. PCP contamination of the
fines is then reduced by biological treatment in a slurry
bioreactor. The relatively clean sand and even the slurry-
reactor treated clay may then be returned to the site. The
BATS is employed in this sequence to treat the washwater
used to separate the sand and fine materials. The Soil Washing
process is the subject of a separate SITE demonstration pro-
gram at the MacGillis and Gibbs site and is being reported
separately.
Field Immunoassay for Pentachlorophenol
While the background for this project was being devel-
oped, EPA's Environmental Monitoring Systems Laboratory
(EMSL) in Las Vegas was searching for a facility where a
new field method for monitoring pentachlorophenol in waste-
waters could be studied under real-world conditions. The
BioTrol demonstration project at the MacGillis and Gibbs site
was an ideal environment to evaluate this technique in parallel
with the extensive analyses being done as part of the demon-
stration. Consequently, arrangements were made to have EPA's
contractor personnel carry out field tests of this method as part
of their assignment.
• Heat Exchanger
Table
Control Panels
Blower
• Temper Tank
Figure A-2. BioTrol, lnc.'s mobile aqueous treatment system.
18
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The test itself, developed by Westinghouise, takes advan-
tage of the inhibition of bacterial enzyme activity that occurs
when a target chemical, in this case pentachlorophenol, is
present The inhibition is observed by a color change in a
reagent matrix and is readily quantified using standards. Only
very small samples of material are needed and the results are
generated within an hour. The field evaluation sought to
determine the sensitivity of the test in real-world wastewater
matrices, its convenience and reliability in the field when used
by relatively inexperienced personnel and, most important,
how well results correlated with the standard GC/MS analysis
and larger scale laboratory immunoassays.
Reference is included to make the reader aware of this
effort and die potential availability of the method. A report
documenting the procedure, equipment, and results of this
study will be available under the SITE program.
Influent
Heat
Recovery
Effluent
toPOTW
*' or Reuse
Conditioning
Heat
Air Air Air
Air"'
Figure A-3. Schematic of BATS system.
Vent
Influent
Overflow
Weir
Effluent
Air Diffuser Pipe
Packing
Figure A-4. Schematic of bioreactor.
19
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Appendix B
Vendor's Claims
Introduction
The technology developed by BioTrol for treatment of
wastewateis involves the use of naturally occurring microor-
ganisms for the destruction of dissolved organic contami-
nants. Since the early 1900s biological treatment has been
utilized for the treatment of municipal wastewaters, and has
long been recognized as a low cost, highly effective technique
for the destruction of organic compounds. Only recently,
however, have the microbial pathways for the biodegradation
of widespread priority pollutants been elucidated to the point
where effective treatment systems can be applied. Using
naturally occurring microbial systems, the effluent produced
by this technology is substantially reduced in concentrations
of many hazardous compounds, including PCP, polynuclear
aromatic hydrocarbons (PAHs), gasoline components (BTEX),
solvents, and substituted phenols. Removal efficiencies for
these compounds in the 95 to 99 percent range have been
achieved by BioTrol in on-site demonstrations and full-scale
installations. Concomitant reductions in biochemical oxygen
demand (BOD) in the 75 to 90 percent range have also been
achieved.
While there are several treatment methods for removing
organic compounds by chemical oxidation—such as UV/
ozone, chlorine dioxide, or hydrogen peroxide systems—
these methods often incur very high operating costs (due to
quantity of oxidant required) when applied to wastewaters.
Furthermore, the complete conversion of the organics to car-
bon dioxide and water is often not achieved. On the other
hand, separation techniques, like carbon adsorption, merely
transfer the contaminants to another medium (the adsorbent)
which must then be regenerated, often at a very high expense.
Biodegradation offers the potential to completely miner-
alize the organic contaminants with little or no consequential
risk to the environment, at a much lower cost than that of
systems utilizing chemical oxidation or adsorption. In addi-
tion, biological treatment efficiently removes organics con-
tributing to the BOD of the wastewater, thereby reducing
sanitary sewer surcharges, or even rendering the effluent
suitable for stream discharge. In cases where carbon adsorp-
tion is required as a post-treatment, the removal of BOD
serves to greatly reduce the cost of carbon usage.
Technology Description
Reactor Design
Reactor design is critical to successful implementation of
this technology. BioTrol employs a multi-stage, submerged,
aerated, fixed-film reactor that provides a high biomass con-
centration and, consequently, a reduced reactor volume. This
is known as the BioTrol Aqueous Treatment System or BATS.
The multiple stages create a dispersed plug flow of wastewa-
ter through the reactor. The plug flow configuration is impor-
tant in that contaminant concentrations typically fall in the
range of first order removal kinetics. That is, the rate of
removal is proportional to the concentration of contaminant.
A completely mixed tank system operating at a low effluent
concentration will experience low removal rates. A system
with plug flow characteristics, on the other hand, will experi-
ence the.same low rates in the effluent sections; however, the
influent sections will operate at very high rates, thus yielding
higher overall removal rates than the mixed tank system.
The use of a fixed-film system allows for a long cell
retention time and, therefore, lowered production of excess
sloughed biomass. Moreover, the fixed-film system elimi-
nates the often problematic biomass separation step which is
crucial to successful operation of an activated sludge system.
The BATS can be skid-mounted and fully automated to allow
for minimal operator attention.
Microbial Amendment
Many of the priority pollutants can be degraded by micro-
organisms indigenous to a given wastewater. For these com-
pounds, treatment can be accomplished by simply adding the
appropriate inorganic nutrients and allowing time for acclima-
tion. However, in cases where a highly toxic or recalcitrant
compound is to be treated, the appropriate microorganisms
may be absent. In these cases, treatment can be accomplished
by adding organisms with the appropriate degradative capa-
bilities/This technique, called microbial amendment, is find-
ing increasing use as microbiologists continue to isolate
organisms with novel metabolic pathways.
As an example of microbial amendment, aFlavobacterium
species is used by BioTrol for treatment of pentachlorophe-
nol-contaminated wastewaters. This microorganism can per-
form 'rapid mineralization of pentachlorophenol. at
concentrations up to 200 mg/L.
20
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Applicability
The following is a partial listing of organic contaminants
which can be successfully biodegraded:
Pesticides
2,4-D, pentachlorophenol, dieldrin, parathion,
2,4,5-T, formaldehyde, aldrin, malatltu'on,
low-MW polynuclear aromatics
Solvents
acetone, methyl isobutyl ketone, methylene
chloride, acetonitrile, methyl ethyl ketone,
cyclohexanone, ethyl ether, methanol, cresols,
trichloroethylene and related compounds
Petrochemicals
benzene, ethylbenzene, toluene, xylene,
alkanes, styrene, tetrahydrofuran, alkenes,
diethyl phthalate
Chemical Products
anih'ne, ethylene glycol, chlorobenzene,
benzidine, substituted phenols, ethyl acetate,
hexachlorobenzene, acrylamide
Case Studies
Biodegradation has wide applicability for the treatment
of wastewaters contaminated with various toxic organics. In
fact, treatment of PCP represents a "worst case" in that PCP is
one of the most highly toxic of the common priority pollut-
ants. BioTrol has also had success treating a variety of other
wastewaters with the BATS approach. These waters range
from very high strength process water with high concentra-
tions of substituted phenols to low strength groundwater
contaminated with trace concentrations of benzene.
BTEX-Contaminated Groundwater
Figure B-l shows the performance of a full-scale BATS
unit treating gasoline-contaminated groundwater (benzene,
toluene, ethylbenzene, and xylenes as primary contaminants)
at 15 gpm. This system has consistently performed >99 per-
cent removal of benzene since installation, and the effluent
qualifies for discharge without a polishing step. This system
will ultimately be coupled with an in situ treatment process at
the site. Effluent from the reactor will be lamended with
hydrogen peroxide and reinjected into the aquifer to initiate
treatment of the soil.
Phenol-Contaminated Process Water
Figure B-2 shows the performance of a bench-scale BATS
system for continuous treatment of a process water from a
creosoting operation. The target contaminants in this case
were substituted phenols. Percent removal of total recoverable
phenols remained high even at very high loading rates (up to
420 lb COD/1000 ft3 packed volume/day). The continuous
flow bench-scale study, in this case, was used to generate
design data for a full-scale system.
Solvent-Contaminated Process Water
Table B-l shows the results of another continuous flow
bench-scale study involving treatment of solvent-contami-
nated process water. The target compounds in this case were
methyl ethyl ketone, toluene, and tetrahydrofuran. These re-
moval percentages were achieved at a loading rate of 110 lb
COD/1000 ft.3 packed volume/day and with an influent COD
concentration of about 3000 mg/L. In this case, treatment was
accomplished solely by microorganisms indigenous to the
water.
5000
4000
3000
2000
7000
Influent, ppb
Effluent, ppb
40
30
20
10
10
15 20
25
Days
Figure B-1. Benzene treatment by BATS.
Table B-1. Treatment of Solvent-Contaminated Process
Water
Methyl ethyl ketone
Total BTEX
Tetrahydrofuran
Total Unknown Peaks
Influent
(mg/L)
43.0
1.3
5.7
5.0
Effluent
(mg/L)
<0.005
<0.01
0.014
99.9
>99
>99.7
>99
21
-------
Summary
The BATS technology demonstrated under the SITE
program has wide applicability for treatment of contaminated
groundwalers and process waters. Many contaminants are
amenable to biodegradation by indigenous microorganisms,
and in some cases, microbial amendment can be used to
promote biodegradation of recalcitrant compounds. The BATS
can achieve high removal efficiencies at relatively high or-
ganic loading rates. Contaminants amenable to treatment in-
clude pentachlorophenol, gasoline components (BTEX),
solvents, PAHs, and substituted phenols. Table B-2 summa-
rizes results of laboratory, pilot-scale, and commercial trials
of the system.
100
80
60
40
20
Percent Removal
100 200 300 400
Loading (Ib COD/1000 of/day)
500
Figure B-2. Phenols removal by BATS.
22
-------
Table B-2. BATS Performance Data
Description Scope
(Waste/Loc.)
Woodpreserv.
(GA)
DOE Mfg site
(LA)
Woodpreserv.
(GA)
Woodpreserv
(AL)
Woodpreserv.
(GA)
Woodpreserv.
(AK)
Woodpreserv.
(GA)
Woodpreserv.
(TX)
Tape mfg.
(CA)
-
Woodpreserv.
(Canada)
Gas Station
(MN)
Woodpreserv.
(MN)
Woodpreserv. •
(GA)
Window mfg.
(Wl)
Woodpreserv.
(TX)
Woodpreserv
(MN)
Window mfg.
(IA)
Gas Station
(MN)
Woodpreserv.
(TX)
lab
treat
lab
treat
lab
treat
lab
treat
lab
treat
lab
treat
lab
treat
bench
cont
bench
cont
bench
cont
pilot
pilot /
pilot
pilot
pilot
pilot
comm
(.75gpm)
comm
comm
Contaminants
COD
Total K001
TCE
vinyl chloride
DCE
PAH
COD
total phenols
PAHs
COD
total phenols
COD
PCP
PCP
COD
PCP
totalphenols
COD
MEK-
THF
Cyclohexanone
COD
PCP
totalphenols
COD
BTEX
PCP
Total PAHs
COD
PCP
Totalphenols
COD
PCP
BTEX
totalphenols
COD
PCP
roc
PCP
BTEX
BTEX
totalphenols
total PAHs
Influent
mg/L
1700
70
10
3
10
10
100
2
1.2
2000
6.3
15000
43
4.5
11000
70-80
10-50
5500
40-50
5-10
—
3/00
9-10
5-6
800-850
5-10
90-100
10-13
250-300
10-15
50
10-11000
2-5
1
20-200
500-1500
40-45
80
90-100
7-8
3-5
50-150
5-6
Effluent
mg/L
60
1.3
0.05
<0.005
<0.005
2
70
0.6
0.02
300
0.8
1800
\
3
<0.5
2500
0.2-0.5
99
>99
80
30
70
98
85
87
88
93
>89
77
99
>95
89
>99
>99
76
>94
>88
>56
>98
>97 ,
>90
>95
>40
>75
>99
>75
>98
>38
>99
>97
>99
>90
>94
23
-------
Appendix C
SITE Demonstration Results
Introduction
The goal of this demonstration project was to study the
effectiveness of the BioTrol ATS in removing PCP and PAHs
from wood treating wastewaters. After considering another
site, the MacGillis and Gibbs site in New Brighton, MN
became the prime candidate on the basis of the Remedial
Investigation/Feasibility Study (RI/FS) that led in its inclu-
sion on the National Priorities List in 1984. The RI/FS study
suggested that the groundwater under the site could be heavily
contaminated with both target species. In addition, BioTrol,
Inc. had already treated process water contaminated with
pentachlorophenol in conjunction with its soil washing unit at
the facility.
The MacGillis and Gibbs Company site had been used for
wood treatment since the early 1940s. Creosote was the
preservative until the mid-1950s when a shift was made to
pentachlorophenol in a light oil. Impregnation was carried out
in open troughs, resulting in significant spills and drippage. In
addition, the pentachlorophenol/oil mixture occasionally was
used for weed control throughout the site. In the 1970s,
pentachlorophenol was replaced by the newer chromated cop-
per arsenate process and enclosed pressure kettles were sub-
stituted for the open troughs, thereby eliminating many of the
sources of contamination.-
An adjacent facility, the Bell Pole and Lumber Company,
also was treating wood during the same period. While it is still
unconfirmed, there may be movement of contaminated ground-
water from the Bell site to the MacGillis and Gibbs site. A
disposal area in the western portion of the MacGillis and
Gibbs site also may be a source of soil and groundwater
contamination. Figure C-l presents the general layout of the
facility and the location of two wells that were drilled to
assess the suitability of the site for the SITE demonstration
project.
While the RI/FS sampling results suggested that there
were pockets of creosote and pentachlorophenol contamina-
tion as a result of operations dating back to the 1940s, there
were no groundwater test well results to assure that an appro-
priate wastewater (sufficient flow, suitable levels of penta-
chlorophenol) would be available for the demonstration.
Therefore, two wells were drilled in locations based on the RI/
FS reports (Figure C-2). During the drilling, rapid tests for
pentachlorophenol (PCP) were carried out at increasing depths
using the High Pressure Liquid Chromatography (HPLC)
method devised by BioTrol. [Data in the QA comparison
study conducted as part of the QA program confirmed that
BioTrol's HPLC data are comparable to data from EPA's
SW-846 Method 8270.] The first of the two wells contained
about 45 mg/L of PCP, adequate for the demonstration (al-
though a higher level would have been preferred) and was of
adequate flow (>5 gpm) for the demonstration project This
well was fully developed by pumping for about 69 hours;
further PCP analyses at about 10 hour intervals (by HPLC)
confirmed the 45 mg/L range. The second well, located about
65 feet away, contained an unacceptably high level of oil (a
lens of oil), significantly lower PCP levels, and inadequate
flow when subjected to a pump test of flow (Table C-l).
Upon consideration of the BioTrol process and the ground-
water available, it was determined that the key variable that
could be tested was flow rate. At a constant concentration, this
allowed the capacity of the system in terms of pentachloro-
phenol removal to be studied. To avoid shock loading and the
need for re-acclimation, the flow rate into the system was
incrementally increased, allowing it to stabilize at each flow
rate so that analytical results of "steady state" operation could
be obtained. Three experimental stages of two week duration,
at 1,3, and 5 gpm flow rate, were selected on the basis of the
capacity of the pilot scale system.
Influent, effluent, and intermediate points in the bioreactor
were sampled by 24-hour composites for PCP or full semi-
volatile organic scans during each regime. Other constituents
were sampled and analyzed at varying frequencies and loca-
tions, including the well, during each experiment using appro-
priate grab or compositing techniques. Included were oil/
water, total and volatile suspended solids, volatile organics,
nitrogen and phosphorus nutrients, and heavy metals. Chlo-
ride and TOC analyses were given particular attention since
changes in these parameters should parallel pentachlorophe-
nol destruction and establish whether mineralization of the
pentachlorophenol does occur, as claimed by the vendor.
Air leaving the bioreactor was also monitored for volatile
organics and semivolatiles, before and after a carbon adsorber,
to determine whether stripping was a significant contributor to
removal. The Quality Assurance Project Plan also called for
the sludge in the bag filter to be collected and analyzed to
learn if absorption of pentachlorophenol on the biological
growth was a contributor to removal; however, the nature of
the filter and the small amount of sludge produced allowed
only limited analyses. The effluent from the aqueous carbon
adsorber was also analyzed to assure that the discharge met
the 2 mg/L pentachlorophenol limit imposed by the POTW.
24
-------
M
I
1 POP
\
Process <
Area I
i 1
Figure C-1. MacGillis & Gibbs site.
Field Activities
BioTrol personnel were responsible for acclimating the
system over about a two week period using the selected well
water in a recycle mode. The system was inoculated with a
PCP-specific flavobacterium after one week. EPA contractor
personnel initiated sampling when BioTrol advised EPA that
the system was acclimated. A separate laboratory trailer was
available where contractor personnel could prepare equip-
ment and samples, although much of the sample handling was
done outside.
Test Procedures
Composite samples were collected in ice-chilled Isco
samplers for 22 hours. Grab samples were taken on a predeter-
mined schedule using transfer beakers or by direct immersion
of bottles and then were processed in a manner similar to that
for the composite samples. Samples were transferred to bottles,
inhibited or preserved as called for by the individual methods,
labelled, sealed, and shipped in ice-filled coolers to off-site
laboratories by overnight express. Flow was occasionally
measured manually at the well as well by monitoring readings
from a flowmeter on the effluent line. The temperature, dis-
solved oxygen, and pH in the three chambers of the bioreactor
and the groundwater were also documented to assure that no
gross change in conditions affected reaction effectiveness.
Sampling points are indicated on the schematic of the system,
Figure C-3. The sampling schedule, analytical protocols used
and results, and QA/QC protocols are described in the Tech-
nology Evaluation Report. The ongoing QA program allowed
for the collection and reporting of high quality data.
25
-------
Ttbl» C-1. Analyses of Wells on MacCillls and Glbbs Site
WuHNo.
Max. Flow
(gpm)
Avg. PCP
(mg/L)
1
2
28
3
45.9'
11.2"
• by HPLC during 69 hr well pump test
* by HPLC after development, well not "pump tested"
Vented Stainless
Steel Cap
Steel Casing with
Cap & Lock
Bottom of
Borehole
4* I.D. Schedule 40 Type 304
Stainless Steel Riser
Cement Bentonite Grout
3" x 5' Steel
Guard Post
Land Surface
4" I.D. Schedule 40 Type 304
Stainless Steel Screen
(0.020' Slot)
Not to Scale
Flush Plug
Figure C-2. Well construction.
26
-------
Nutrients,
Caustic
Liquid Sample
(Well Water)
Air Sample
0
Liquid Sample
#3
Carbon
To Air
Air Sample
0
Liquid Sample
100 gal.
Conditioning
Tank
Liquid Sample
(Influent)
©
Note: Circled numbers refer
to sample points
"Active"
Biomass
Sample
0
Liquid Sample
(Effluent)
Solids Sample
#7
ToPOTW
or
MacGillis
and Gibbs
Liquid Sample
^~^\
#8
Figure C-3. BioTrol aqueous treatment system (BATS) with sampling points shown.
With the exception of an inoperative dissolved oxygen
meter at the outset of the project, all process and sampling
equipment functioned well. The design of the reactor and the
mobile trailer is such that space was very limited and some
improvisation was necessary in collecting certain samples.
Air monitoring of the exhaust stack from the bioreactor
before and after the carbon adsorber used a modified MM5
stack method and XAD adsorbent resin traps. Modifications
were necessary when determining air flow through the sys-
tem, because of the narrow diameter of the stack (3-4 inches).
These tests were carried out about once per week for three
weeks.
The sludge in the bag filter could not be readily, consis-
tently, nor completely removed from the bag. Eventually, the
bag was removed at arbitrary times and cut up so that solids
could be flushed from the fabric for sampling purposes.
Results
System Parameters
Nitrogen as nitrate, nitrite, and ammonia, and phosphorus
as phosphate were monitored over the course of the investiga-
tion. No unusual effects were observed; the presence of re-
sidual nutrients in the effluents suggests that reaction
(biodegradation) was not inhibited by insufficient nutrients.
Similarly, dissolved oxygen was measured in each cham-
ber of the reactor twice daily over the course of the study and
found to remain reasonably constant between 5 and 6 mg/L.
There was a slight increase in the dissolved oxygen as the
27
-------
water passed through the system and was aerated by the air
sparger system. The incoming groundwater contained <1.0
mg/L dissolved oxygen.
Some variation in temperature was observed throughout
the project (Table C-2). The temperature of the influent to the
biorcactor was lower in the 3 gpm (14-17 C) and the 5 gpm
(14-21 C) studies than in the 1 gpm study (22-25 Q. This
probably was partially due to a decrease in the temperature of
the groundwater over the course of the program, and possibly
also due to inadequate heat exchange to the incoming ground-
water, which was at a lower temperature (11-16 Q. The
heater was not used. As expected, temperature increased
slightly as the wastewater passed through the system, i.e., the
effluent temperature was higher than the influent temperature
in all three study segments.
Table C-2. Temperature Across BIoTrol System
Temperature fC, avg)
Flow Gdwater
(gpm) #r
1 21
3 11
S 13
Influent
#2
23.4
15.7
14.6
Midpt
#3
24.6
20.4
20.8
Midpt
#4
24.5
20.4
21.0
Effluent
#5
24.8
20.9
20.9
While vendor specifications called for a pH of about 7.3
in the tempering (conditioning) tank, the pH measured in the
three chambers of the bioreactor usually was somewhat higher,
particularly at the lower flows and, at least at the 1 gpm flow,
appeared to increase across the system. The pH of the ground-
water was consistently in the range of 6.7-6.9 standard units.
Initial oil and grease values of approximately 50 mg/L
were reduced to <10 mg/L by passage through the system.
Total suspended solids levels (TSS) in the incoming well
water were quite low (<5 mg/L) and increased (to 54 mg/L at
1 gpm, 26 mg/L at 3 gpm, and 18 mg/L at 5 gpm) over the
course of the study (Table C-4). At these levels, the suspended
solids (sloughed biomass) probably do not represent a signifi-
cant mechanism for removal of organic pollutants. Volatile
suspended solids represent approximately 40% of the total
suspended solids in the effluent, increasing slightly (to ~50%)
at the highest flow rate.
Pentochlorophenol Removal
With the receipt of the first PCP analytical data generated
by SW-846, Method 8270, it became clear that the anticipated
results were not being obtained. Influent PCP values (com-
posite samples) were significantly lower than the concentra-
tion at the well (grab samples). Analyses by BioTrol using
grab samples just before the bioreactor (Point "B" in Figure
C-3) and the HPLC method agreed with the higher well data.
At first it was thought that the difference might have been due
to foaming during the extractions for the analytical procedure
(SW846 Methods 3510/8270). While that problem persisted
throughout the study and did affect the recovery achievable
for the samples, it became clear that it was not the cause of the
drastic differences between the well or BioTrol's samples and
the influent chamber samples.
Additional QA testing indicated that BioTrol's HPLC
method for PCP and EPA's Standard Method (SW-846, Method
8270) are comparable when extraction efficiency is taken into
account. This information aided in establishing that the well
water concentrations of PCP were actually better representa-
tions of the influent concentrations than the influent data by
the SW-846 method. Consequently, removal efficiency deter-
minations (Table C-4) were based on well water and effluent
data (both by Method 8270) instead of the influent samples.
Other possible explanations for the anomaly in results
were then considered, including absorption on the walls of the
bioreactor, separation of a PCP-in-oil layer, and backmixing
under the underflow weirs separating the chambers.
Backmixing appears to be the best explanation for the low
values obtained for the influent and the gradual improvement
in agreement between well water data, BioTrol HPLC data,
and influent data as the flow rate was increased each two
weeks. Well water (sampling point #1) and influent (sampling
point #2) PCP values in Table C-4 are much more in agree-
ment at the 5 gpm flow than at the 1 or 3 gpm rates, suggesting
that the importance of the backmixing decreases as the flow
increases.
Grab samples also were taken from a "T" just before the
influent chamber (point B on Figure C-3) and analyzed by
BioTrol's HPLC method. These samples, which were not
subject to the backmixing, agreed with the well samples
(sampling point #1). Consequently, the grab samples from the
well were primarily used in determining PCP removal. Within
limits discussed later, free chloride and TOC data at the
several sampling points also support this conclusion.
On the assumption that the correct concentration of PCP
in the influent was about 45 mg/L in the 1 gpm study but was
about 7 mg/L in the first chamber of the bioreactor, it was
estimated that approximately 5 gallons was "leaking" back
through the system for every gallon introduced.
Nevertheless, using either the well water or sampling
point #1, it is clear that the BioTrol Aqueous Treatment
System does effectively remove PCP from the groundwater as
it moves through the system. Concentrations of PCP after
treatment (but before carbon polishing) were about 0.13 mg/L
at the 1 gpm flow rate and increased to an average of 0.99i0.49
mg/L at the 5 gpm flow rate.
The BATS achieves at least 95% PCP removal at the 5
gpm flow rate and 99% at the lower flow rates. Even using the
lower influent chamber analytical results (#2), percent re-
moval is still excellent
Based on the estimated mass of PCP introduced to the
system over each two week experimental period, and assum-
ing that all PCP is lost by biological degradation, mass remov-
als of >95% are consistently achievable (Table C-5).
28
-------
Table C-3. A verage TSS and Oil Across the BioTrol System
Ground/water
Flow TSS O/G
(gpm) mg/L
TSS
Influent
mg/L
O/G
TSS
Effluent
mg/L
O/G
1
3
5
2.5 ±0.7
13± 12.7
1.5± 0.7
54.5+2.1
61.0 ± 1.4
47.5± 10.6
29.6 ±9.4
24.2+ 17.6
15.7±8.9
57.5 ± 10.7
37.8 ± 14.9
50.8 ± 10.5
53.6 ±6.6
26.3 ±11.1
22.5 ± 9.5
Note: Complete data can be found in the Technology Evaluation Report.
6.0± 0.4
6.0 ± 1.3
8.0 ±2.4
Table C-4. Average Pentachlorophenol Removal by BioTrol System
Flow PCP
(gpm) (#1)
Gdwtr
1 42.0±7.1a
3 34.5 ±7.8"
5 27.5±0.7a
PCP
(#2)
Infl
6.9 ±3.4
19.0 ±5.8
24.2 ±6.8
PCP
(#5)
Effl
0.1 3 ±.25
0.34 ±.15
0.99 ±.49
Removal
Gdwtr/Eff
99.8
98.5
96.4
Infl/Effl
98.1
98.2
95.9
Comparison of analytical results for PCP in as-is samples
and in filtered samples indicated that very little if any of the
PCP was absorbed on the filterable solids. While there were
measurable concentrations of PCP in the sludge samples, the
amount of sludge exiting the bioreactor was so small that this
is not considered a significant contributor to the removal of
PCP from the system. Similarly, the low concentration of oil
in the effluent (<10 mg/L) strongly argues against loss of PCP
by extraction into that phase. Analyses of the air exhausted
from the bioreactor confirmed that no detectable quantities of
pentachlorophenol were lost by this route.
Table C-5. Mass Removal of Pentachlorophenol
Week
1
2
3
4
5
6
Flow
(gpm)
0.98
1.0
2.92
3.02
5.14
5.03
Total PCP
In (Ibsf
(#1)
3.32
2.65
8.39
6.29
9.99
10.13
Total PCP
Out (Ibs)
(#5)
.178
.002
.077
.075
.533
.221
Removal
(%)
94.6
99.9
99.1
98.8
94.7
97.8
' Based on well water (#1) analyses
Chloride and TOC monitoring of the grotindwater and
the effluent produced results that are consistent with the
vendor's claim that the pentachlorophenol is mineralized,
but indicate that other contributors to chloride and TOC are
present. Table C-6 summarizes the actual changes in chlo-
ride and TOC and the changes calculated on the basis of the
observed decrease in pentachlorophenol.
Removal of other organic constituents, even including
oil or biomass, may explain why the observed decreases in
TOC levels are greater than calculated. The concentrations
of mono-, di-, and trichlorophenols (by SW846 Method
8270) all were below the detection limits in the semivolatile
scans of the groundwater, influent, and effluent; however,
the detection limits were often quite high since pentachloro-
phenol was the primary "target" of the analyses. It is also
reported that commercial pentachlorophenol may contain as
much as 20% by weight of tetrachlorophenols (TCPs). If, for
example, the PCP were accompanied by 20% by weight as
tetrachlorophenols (which were not target analytes), this
would mean 8.4 mg/L of TCPs were present and could
contribute 5.1 mg/L of chloride. [Review of two archived
scans of groundwater indicated total TCP contents of about
4% and 10% of the PCP concentrations.] And, if all the
partially chlorinated isomers (mono-, di-, and
trichlorophenols) were present at just below their detection
limits' in the well water sample, they could contribute an
additional 6.4 mg/L of chloride. Table C-7 summarizes the
calculated chloride yields during the 1 gpm study.
Polynuclear Aromatic Hydrocarbon Removal
Concentrations of the various PAHs in the incoming well
water were lower than anticipated and below the detection
limits. The high detection limits for PAHs in the semivolatile
organics GC/MS scans, often in the range of 2 mg/L when
analyzing for PCP in the 10-50 mg/L range, precluded mea-
surements at (j.g/L level. Two values for total PAHs obtained
during the predemonstration well drilling effort, 145 and 295
mg/L, are consistent with the absence of PAHs at the indi-
cated detection limits during the project. The lack of specific
values for PAHs in the well water and/or the influent makes it
impossible to assess the removal of these chemicals across the
system. Specific PAHs also were not measurable in the efflu-
ents even though the detection limits were now 10-100 \ig/L.
In other studies by BioTrol it was demonstrated that PAHs are
removed by the BATS (see Appendix D). Limited analyses on
a few sludge samples for PCP or PAHs indicated detectable
quantities of selected PAH compounds, as noted in Table C-8.
Because of the small amount of sludge discharged, accumula-
29
-------
lion of PAHs (or PCP) in the sludge is not a significant
contributing mechanism for the removal of these species.
Monitoring of the reactor exhaust air, before and after the
carbon adsorber, indicated that some stripping of polynuclear
aromatic hydrocarbons does occur, probably due to the air
bubbled through system (Table C-9). Additional air was also
introduced to the stack during the monitoring, which may
explain the observation that some naphthalene did pass through
the carbon, possibly by an air "regeneration" phenomenon.
Small amounts (=< 1 |ig/L) of phenol, 2,4-dimethyl phenol,
and other, higher molecular weight PAHs (dibenzofuran and
fluorcne) also were found occasionally in the pre-carbon
samples but not in the after-carbon samples.
PolychlorinatedDibenzo-p-Dioxinsl
Dibenzofurans
Selected samples were scanned for the .various dioxins
and furans using high resolution GC coupled with low resolu-
tion MS. A number of the chlorodioxin and furan species were
found to be present in the influent and the effluent, usually at
the nanogram/liter level. The 2,3,7,8-TCDD isomer was re-
ported at above detection limit in only one sample (62 ng/L in
an effluent sample). Review of the data (Table C-10) also
indicates an increase in concentration for all the isomers as the
wastewater moves through the reactor, possibly due to accu-
mulation of dioxins on the biomass, which does increase
across the system and is sloughed off into the effluent
Table C-ll presents dioxin/furan data for the sludges
collected in the bag filter during the study. Some dioxin/furan
isomers were found in the sludge, in the ng/gm range based on
wet weights. This is not considered a problem in light of the
small amount of sludge generated, except that the sludge may
require disposal as a dioxin-contaminated material.
Heavy Metals
While arsenic and various heavy metals were found in the
groundwater at low concentrations, these constituents pass
through the system with little change in concentrations (Table
C-12)—with the exception of the first effluent sample, which
shows anomalous results
Volatile Organics
Analyses for volatile organics indicated that few of these
materials were present in the groundwater, even at low con-
centrations. Levels were further reduced by passage through
the treatment system, probably by stripping. Volatile organics
were not detected in the exhaust air collected from the reactor.
Biomonitoring
Biomonitoring with two different species, minnows and
water fleas, was carried out on the groundwater, the influent,
and the effluent. The results confirmed that the groundwater
was toxic to these species and that treatment removed the
cause of the toxicity. The results in Table C-13, presented as
LC(50) values, reflect the percentage of groundwater, influ-
ent, or effluent in the water that could be tolerated in the test
water before 50% of the species succumbed. When 1% or
even less of either the groundwater or the influent is incorpo-
rated in the test water, 50% or more of the test species die
during the test period. After treatment, the effluent has essen-
tially no adverse effect on either species during the test period,
even when 100% effluent is the test water.
Table C-S. Comparison of Chloride and TOC Changes with PCP Removal
Increase in
Flow PCP Cl(fd)> Cl(calc)?
(gpm) change rng/L
TOC(fd)
Decrease in
mg/L
TOC(calc)
1
3
5
-41.9
-34.1
-26.5
+40.2
+37.2
+27.2
+27.9
+22.7
+17.6
-25.5
-31.5
-21.0
-11.3
-9.2
-7.0
•fd * found; (effluent - groundwater)
»ca/c - calculated from change in PCP, as 5CI/PCP & 6C/PCP
Table C-7. Potential Chloride Contributions from Partially Chlorinated Phenols
Substance
2-Monochloro
2.4-Dlchtoro
2,4,6-Trichloro
2,4.5-Trichloro
Totracbloro
Possible non-PCP total
Pentachloro
Total Calculated
Detection Limit
mg/L
2
2
2
10
na, 2PCP1
42 found
Chloride Yield
mg/L (calc)
0.6
0.9
' 1.1
5.4
5.1
13.1
27.9
41.0
'Estimated only, on the basis that PCP may contain as much as 20% tetrachloro- isomers.
30
-------
Table C-8.
Sample
B-09-07S
C-OS-07S
C-10-07S
C-10-15&
Sludge Analysis Results
Pollutant
POP
Pyrene
Chrysene
Benzo(b)fluoranthene
Benzo(a)pyrene
PCP
Anthracene
Benzo(k)fluoranthene
PCP
Anthracene
Pyrene
PCP
Cone
(mg/kg dry)
34
15
5.3
10
6.1
170
92
74
2.7
3.0
2.5
18
Phenanthrene
1.9
3 This sample is sludge found adhering to walls of bioreactor.
Table C-9. PAHs In Air Emissions from Bioreactor
Test Liquid
# Flow at
Time of Test
1
2
3
4
5
a b.c. - be
1
1
1
3
5
fore carbon atisi
Naphthalene
b.c.' a.c.a
r
6.5
3.8
4.6
4.6
34.6
nrht*r
0.6
1.6
1.7
0.6
1.1
2-me Naphthalene
b.c. a.c.
4.7
3.0
3.7
6.7
47.9
nd"
nd
nd
nd
nd
Acenaphthene
b.c. a.c.
7
0.5
0.3
nd
0.7
2.8
nd
nd
nd
nd
nd
a.c. = after carbon adsorber
nd = not detected
Table C-10. Dioxins/Furans Found in System
Influent/Effluent Concentrations
(ng/L)
Week HpCDD
1
2
3
4
5
6
d/4
&U/7SW
32/180
<4.4/4.3
25/62
HpCDF
<10/20
<2.8/30
2.1/7.0
HxCDD
j
<2.2/8.8
HxCDF
<1. 5/4.1
OCDD
340/1100
170/910
28/42
<8.6/28
140/390
OCDF
<17/23
<7.3/40
<4.8/12
TCDD 2378-
<3.2/62
'- ' indicates the isomer was absent or below detection limit in both influent and effluent. ~ "^ — —
31
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Table C-11. Dloxlns/Furans Found In Sludge
Sludge Concentrations
(ng/gm)
Wook HpCDD
HpCDF
HxCDD
HxCDF
OCDD
OCDF
TCDD
2378-
1 260
2 no sample
46
13
13
1900
41
:.05A
<.054
3
4
5
6
no sample
25
23
3.9
4
1.4
1.5
1.7
1.7
190
0.98
140
3.0
<.22
3.1
<.088
•f.08
<.088
<.08
Table C-12. Metals Found In System
Wook
As
Concentration of Metals (Groundwater/Effluent)
Cu
Ni
Cr
Pb
Zn
1
1
2
3
V
A
*r
5
6
ni?
• A'-
» DL
64/220
4.1/5.6
5.4/5.3
6.5/7.7
5.9/5.7
1.5
25/4400
19/37
20/23
—/19
—/23
ND/30
12
60/390 ND'/450
54/67 ND/8.0
81/73 ND/ND
—/60 —/ND
67/71 ND/23
91/87 7.0/ND
21 6.7
7.7/580
11 /ND
ND/11
—J8.1
3.9/6.1
6.9/5.9
2.9
32/20,000
20/20
ND/8.0
—/13
23/30
20/17
5.7
- indicates the analysis was not carried out; an ND indicates the concentration was below detection limit.
= Detection limit
Table C-13. Acute Bfotoxlcity of Groundwater and Treated Effluent
Wook
1
y
3
4
5
6
Flow
(gpm)
1
1
3
3
5
5
LC(50;-Daphnia"
LC(50)-Minnovf
Grdwtr Infl. Effl. Grdwtr Intl.
(% Wastewater/Test water)
— 0.35
— 0.84
— 0.26
— 0.54
1.0 0.61
0.27 0.66
100
100
100
100
100
100
— 0.3
— 1.07
— 0.43
— 0.3
0.22 0.20
0.22 0.20
Effl.
100
100
100
35
100
100
48 hour static test at 2CPC, Daphnia magna
* 96 hour static test at2CPC, Pimephales promelas
32
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Appendix D-l
Full Scale Wood Preserving Site
Introduction
The subject of this study is a wood preserving facility
using the Boultonizing process that generates a process water
contaminated with creosote-derived phenolics, polynuclear
aromatic hydrocarbons (PAHs), and aromatic compounds ex-
tracted from the wood. The BATS unit offered an opportunity
to treat this wastewater biologically in a compact, efficient
manner with minimal operator attention.
The process water to be treated contains significant oily
material. It is treated in two stages for oil/water separation and
then cooled in a cooling tower. Water from the cooling tower,
which was previously discharged to an on-site lagoon, was
treated in the pilot study and, subsequently, in the commercial
unit. The character of, the feedwater varied considerably,
depending on the type of wood treated, rainfall, and evapora-
tion rates (Table D-l).
Table D-1. Characteristics of Phenolic Process Water
Constituent Average Range
(mg/L) (mg/L)
Phenols
SCOD
BOD
TSS
Oil/grease
pH
Temperature (F)
129
1059
752
104
28
11-327
412-1912
75-1200
22-659
8-270
6-9
80-90
Pilot Scale Studies
A pilot scale demonstration study using a 3-celled mobile
unit with a 15 gpm flow capacity was carried out over six
weeks at flow rates of 2 gpm and 1 gpm. Influenit and effluent
samples were collected daily as 24-hour composites while the
bioreactor cells were grab-sampled. Key analyses were total
recoverable phenolics (TRP) by Standard Method 510.B and
chemical oxygen demand (COD) by the OI Corp. method. In
addition, biochemical oxygen demand (BOD), oil and grease,
and total suspended solids (TSS) were also analysed. On three
occasions during the course of the pilot demonstration, samples
were analyzed by EPA Method 610 for polymiclear aromatic
hydrocarbons (PAHs).
Based on analytical results from a pilot unit (Figure D-l),
effluent concentrations of phenols were almost always below
1 mg/L, corresponding to an average phenolics removal of
>99%. Decreases in BOD and COD, while significant, were
not as great, possibly due to sloughed biomass. Variations in
TSS indicate a cyclic character to the TSS values, suggests
that solids accumulation occurs followed by solids release.
PAH removal was in the range of 80+%, but elevated PAH
levels for total samples (including sloughed solids) from the
middle cells suggest that adsorption of PAHs on solids as well
as biodegradation is occurring (Figure D-2).
Commercial System Evaluation
Based on the success of the pilot scale demonstration in
removing phenolics from the aqueous wastewater, a commer-
cial (30 gpm) unit was installed in August 1988. After a two
week acclimation period (no specific bacterium was added),
the unit has been in continuous operation with the flow rate
starting at 20 gpm and then increased to the design rate of 30
gpm. The effluent is discharged to a POTW. Based on the
results for the first 5 months of operation (Table D-2), the
system has produced effluent with an average phenolics con-
centration below 1 mg/L with minimal operator attention.
Table D-2. Wood Preserving Wastewater Treatment by BA TS
Month Phenolics in Effluent (mg/L)
August
September
October
November
December
5 Month A verage:
0.12
0.058
0.14
0.20
1.11
0.33
Cost Data
Operating cost data were developed on the basis of opera-
tion of the commercial unit. Assuming a 30 gpm flow rate and
an influent with 1000 mg/L of BOD and 200 mg/L of phenols,
the operating costs were as shown in Table D-3.
Conclusions
Based on the pilot scale studies and operation of the
commercial unit for several months, the BATS is a cost-
33
-------
effective means of removing phenolics and PAHs from this Table D-3. Operating Cost for BATS Commercial Unit
wastewater. Cost Item $/1000 gallons
The nature of the BATS system is such that it requires a Electricity (@ $0.06/Kwhr)
minimum of labor relative to conventional activated sludge Nutrients (@ $o.71/gallon)
systems where trained personnel may be needed to assure that Labor (10 hr/wk @ $15/nr)
optimum sludge separation and return is carried out. Total
0.15
0.14
0.49
0.78
30 35 40 45
Figure D-1. Phenolic* removal In commercial BATS.
34
-------
I
I
o
Influent
Cell1
Cell 2
Effluent
Location
Figure D-2. PAH removal in commercial BATS.
35
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Appendix D-2
Tape Manufacturer
California
Introduction
A tape manufacturing facility in California produces about
15,000 gpd of solvent-contaminated process water. Contribut-
ing to a high COD are toluene, xylene, methyl ethyl ketone,
tetrahydrofuran, and cyclohexanone. Currently, the plant uses
activated carbon pretreatment prior to discharge to the POTW.
Biological treatment was considered as an alternate, less
costly treatment
A bench scale continuous flow evaluation of biological
treatment using the BATS was carried out Because of high
variability in wastewater loading, the goal of the investigation
was to evaluate the effectiveness of the system at various
organic loadings, in addition to the removal of specific con-
taminants.
Bench-scale Study
The bench scale continuous flow studies were carried
out using a 55 gallon drum of process water shipped to the
BioTrol facility. The system consisted of a 4 in. ID translu-
cent PVC column packed to a depth of 12 in. with 1 in.
Intalox PVC saddles to simulate the structured PVC packing
used in a commercial unit. Air was injected at the base. The
column was inoculated with activated sludge from a POTW
and acclimated over 10 days. Continuous flow operation was
then maintained for 1 week at each of 3 flow rates: 2,4, and
8 L/day, corresponding to loadings of 110, 235 and 485 Ib
COD/1000 ft3 of packing/day.
Results
Samples were removed by BioTrol and measured for the
parameters noted in Table D-4 using standard methods.
Biological treatment effectively removed 99% of the
specific components of concern with only slight fall off in
efficiency when the loading rate was increased from 110 to
235 lb/1000 ftVday. Final effluent with residual concentra-
tions of 5 to 15 (ig/L were achieved at the lower loading and
somewhat higher at the higher loading.
The difference between removal efficiency for specific
components and that for COD is consistent with the presence
of other, more recalcitrant constituents. (Other tests indicate
that stripping of volatile organics accounts for less than 10%
of their removal.)
Cost Data
Using the removal data developed in the bench scale
study, cost data were developed for a commercial system with
a 10 gpm capacity. On that basis, the total anticipated operat-
ing cost would be $3.51/1000 gallons of wastewater as shown
in Table D-5.
TabloD-4.
Parameter
BATS Removal Efficiency—Tape Process Water Table D-5.
Influent
mg/L
Loading: 100 lb/1000 ft'/day
Tokione, xylene 1.3
MEK
THF
COD
43.0
5.7
3178
Loading 235 lb/1000 ft'/day
Toluene, xytene 1.3
MEK 43.0
THF 5.7
COD 3178
Effluent
mg/L
<0.01
<0.005
0.014
758
0.06
0.55
<0.05
1413
Removal
%
>99
>99.9
>99.7
76
95
98.7
>99.1
55
Operating Cost for 10 gpm BATS
Item $/1000gal
Nutrients (liquid fertilizer)
Electricity (for pumps)
(2 Ib oxygen/hp-hr and
10 gpm effluent pump @ 50 ft head)
Labor (10 hr/wk @ $20/hr)
Base for neutralization (NaOH)
Total
0.32
0.37
1.98
0.84
$3.51
36
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Appendix D-3
BATS Treatment of BTEX
Minnesota
Introduction
A truck stop in Minnesota experienced widespread soil
contamination by gasoline from leaking underground storage
tanks. In addition to removing the tanks and highly contami-
nated soil, it was necessary to treat soil beneath buildings and
groundwater to prevent spread of a contaminated plume.
BioTrol proposed that both goals could be achieved by
above-ground treatment of the groundwater in a BATS, fol-
lowed by reinjection of the treated water to stimulate in situ
bioremediation of the soil. Laboratory studies demonstrated
that with proper additions of nutrients and oxygen, the indig-
enous microflora were capable of destroying benzene, tolu-
ene, ethyl benzene, and xylenes (BTEX) in the soil to below
detectable levels in 8 days. Since this remediation scheme
depended on initial above-ground treatment to levels suitable
for reinjection, a pilot scale evaluation of the BATS was
deemed to be necessary.
Pilot-Scale BATS
A single column pilot-scale BATS was installed at a gas
station in the Minneapolis area. The reactor column was 1 ft in
diameter and filled to 9-ft depth with 1 in. Mtalox PVC
saddles to simulate the structured PVC packing used in the
full scale unit. The system provided 1.6 hr of residence time.
The system was first acclimated for 2 wk with no addition
of bacteria except that in the groundwater. The reactor was
then sampled daily for 1 wk, using composite samples of
influent and effluent taken with a zero headspace sampling
device. Analyses of these samples confirmed that >99% re-
moval of BTEX could be achieved with an influent ranging
from 1900 to 15,000 pg/L, and effluent concentrations of <20
|4.g/L for individual components were achieved. The BTEX
results are summarized in Table D-6.
Table D-6. BETX Treatment with the BA TS
Day
Influent
Effluent
Removal
1
2
3
1962
4700
15300
<80
<80
<80
>96
>98
>99
Full-Scale BATS
On the basis of the pilot study it was concluded that the
process was very effective at removing BTEX. A two-stage
reactor was installed at the contaminated site to be used in
conjunction with a closed loop groundwater extraction sys-
tem. Modelling of shallow groundwater flow was used to
design the extraction well and infiltration gallery network.
The BATS is currently treating groundwater at a 15 gpm
flowrate. With a groundwater temperature of 50°F, no heat
input has been found necessary to maintain reactivity. With
influent BTEX concentrations of approximately 4200 pg/L,
consistent reductions to <80 \ig/L have been achieved. Mea-
surements of BTEX concentrations in the air exhaust from the
reactor established that air stripping accounts for removal of
only 5 - 10% of the removed BTEX.
Cost Data
The operating and maintenance cost of the combined in
situ and above-ground treatment is expected to average about
$9000/yr. Total cost of remediation, including capital, mainte-
nance and operation, but excluding groundwater monitoring
and project management fees, is approximately $165,000 with
a 3-yr anticipated project life. More detailed information is
not available at this time.
37
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Appendix D-4
Pilot Plant BATS
Minnesota
In the fall of 1986, the feasibility of treating contaminated
groundwater at a wood preserving site in Minnesota was
evaluated in a 9-month pilot study using the BioTrol Aqueous
Treatment System. The study was funded by a grant from the
U.S. Geological Survey.
The purpose of the study was to establish the long term
effectiveness of the BATS for such wastewaters, particularly
for the removal of PCP and, secondarily, for PAHs. These
materials are commonly found contaminating sites where
wood preserving operations using PCP and creosote had been
practiced over previous decades. The groundwater at the site
contained 60-100 mg/L of PCP based on preliminary studies.
Pilot Plant Study
A simple 30-gallon packed bed reactor was used in the 9-
month pilot study. The system was activated with indigenous
microflora and later amended with inoculations of a
Flavobacterium specific to PCP. The unit was operated essen-
tially in a continuous mode, over the length of the study,
adjusting pH and adding nutrients as necessary. Air was
continuously injected to maintain aerobic conditions.
BioTrol subsequently developed a proprietary bioreactor
design specifically suited to treatment of contaminated ground?
water with an amended, fixed-film microbial system.
Results
The packed bed system effectively removed PCP, PAHs,
and other constituents that were found to be present. The
specific rate of PCP degradation was as high as 70 mg of PCP/
L of reactor volume/hr, well beyond the values normally
reported in the literature. In later work using the proprietary
system design, PCP removal rates between 40 and 50 mg
PCP/L of reactor volume/hr were consistently achieved, with
rates as high as 65 mg/L/hr being achieved. All PCP analyses
were carried out using a HPLC method developed by BioTrol.
Extensive removal of PAHs was also confirmed. While sub-
stantial reductions in COD also occurred, the levels in the
effluent indicate the presence of considerable refractory mate-
rial. Typical results are summarized in Table D-7.
While the influent and effluent data over the 9-month
investigation did exhibit occasional elevated levels in the
effluent, these usually were attributable to mechanical fail-
ures, such as loss of aeration, loss of heat, etc. Daily tabulation
of influent and effluent data indicates that the system had
excellent recovery capability after such upsets.
No cost data is available for this small scale study.
38
-------
Table D-7. Groundwater Treatment In 30 gal Packed Reactor
Constituent Well water
(Ml)
Pentachlorophenol
Acenaphthalene
Naphthalene
Acenaphthene
Phenanthrene
Anthracene
Fluoranthene
Pyrene
Benzo(a)anthracene
Chrysene
Benzo(b)fluoranthene
Benzo(k)ftuoranthene
Benzo(a)pyrene
Dibenzo(a,h)anthracene
Benzo(g,h,i)perylene
Fluorene
lndo(1,2,3-c,d)pyrene
COD (mg/L)
9$000
4,402
1,932
2,041
264
252
466
232
292
171
448
178
211
296
315
545
203
250-300
Effluent
6VQ
nd
nd
81
140
38
20
153
15
9
8
8
7
5
33
4
nd
nd
100-150
Removal
(%)
~100
~100
96
93
86
92
67
94
96
95
98
96
98
89
99
~100
~100
>40
39
* U.S. GOVERNMENT PRINTING OFFICE: 1991—551-565
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