&EPA
United States
Environmental Protection
Agency
Research and
Development
(RD681)
EPA/540/A5-91/002
October 1991
C.
AWD Technologies
Integrated AquaDetox 7SVE
Technology
Applications Analysis Report
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
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EPA/540/A5-91/002
October 1991
AWD Technologies Integrated
AquaDetox®/SVE Technology
Applications Analysis Report
Risk Reduction Engineering Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, OH 45268
CA£> Printed on Recycled Paper
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Notice
The information in this document has been prepared for the U.S. Environmental Protection
Agency's (EPA) Superfund Innovative Technology Evaluation (SITE) Program under
Contract No. 68-CO-0047. This document has been subjected to the Agency's peer review
and administrative review and it has been approved for publication as a U.S. 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 and Reauthorization Act (SARA). The program is a joint
effort between EPA's Office of Research and Development (ORD) and Office of Solid
Waste and Emergency Response (OSWER). The purpose of the program is to assist in the
development of hazardous waste treatment technologies necessary to implement new cleanup
standards that require greater reliance on permanent remedies. This is accomplished through
technology demonstrations that are designed to provide engineering and cost data on selected
technologies.
This report presents the findings of a SITE field demonstration designed to analyze AWD
Technologies' integrated AquaDetox®/soil vapor extraction technology. The technology
demonstration took place at the Lockheed Aeronautical Systems Company site in Burbank,
California. The demonstration effort was directed to obtain information on the performance
and cost of the technology and to assess its use at this and other uncontrolled hazardous
waste sites. Documentation consists of two reports: (1) a Technology Evaluation Report
(TER) that describes the field activities and laboratory results and (2) this Applications
Analysis Report (A AR) that provides an interpretation of the data and discusses the potential
applicability of the technology.
An extensive Quality Assurance (QA) program was conducted according to EPA QA
guidelines, including audits, data reviews, and corrective action plans. This program is the
basis for the quality of the data derived from the SITE project. Discussions of the QA
program and the results of the audits, data reviews, and corrective action plans can be found
in the TER.
A limited number of copies of this report will be available at no charge from EPA's Center
for Environmental Research Information (CERI), 26 West Martin Luther King Drive,
Cincinnati, Ohio 45268. Requests should include the EPA document number found on the
report's cover. When the limited supply is exhausted, additional copies can be purchased
from the National Technical Information Service (NTIS), Ravensworth Building,
Springfield, Virginia 22151, 703/487-4600. Reference copies will be available at EPA
libraries in the Hazardous Waste Collection. You can also call the SITE Clearinghouse
hotline at 800/424-9346 or 202/382-3000 in Washington, D.C., to inquire about the
availability of other reports.
in
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Abstract
In support of the U.S. Environmental Protection Agency's (EPA) Superfund Innovative
Technology Evaluation (SITE) Program, this report evaluates the AWD Technologies, Inc.,
integrated AquaDetox®/SVE treatment system for simultaneous on-site treatment of
contaminated groundwater and soil-gas. The AWD technology uses an AquaDetox®
moderate vacuum steam stripping system to treat contaminated groundwater and a soil vapor
extraction (SVE) system that uses granular activated carbon (GAC) beds to treat soil-
gas. The two systems are looped together to form a closed system with no emissions. This
report evaluates both the treatment efficiency and economic data based on results from the
SITE demonstration and describes several case studies.
Under the SITE Program, the AWD technology was demonstrated at the Lockheed site in
Burbank, California, in September 1990. The groundwater and soil at the Lockheed site
were contaminated with volatile organic compounds (VOC), primarily trichloroethylene
(TCE) and tetrachloroethylene (PCE). Extensive sampling and analyses were performed on
the groundwater and soil-gas before and after treatment so that system removal efficiencies
could be calculated. All sampling and analyses were performed according to quality
assurance guidelines outlined by the SITE Program.
The 2-week long SITE demonstration consisted of 21 test runs performed under varying
operating conditions. Four operating parameters were varied including: groundwater flow
rate, steam flow rate, stripping tower pressure, and GAC bed regeneration frequency. The
AWD technology was evaluated based on the removal efficiencies achieved for removal of
TCE and PCE from contaminated groundwater and soil-gas. The technology was also
evaluated based on compliance of the effluent groundwater with the regulatory discharge
requirements at the Lockheed site.
The conclusions drawn from these evaluations are: (1) the system can effectively treat VOC
contaminated groundwater and soil-gas; (2) VOC removal efficiencies as high as 99.99
percent can be achieved for groundwater; (3) soil-gas VOC removal efficiencies as high as
99.9 percent can be achieved; (4) the effluent groundwater was in compliance with the
regulatory discharge requirements of 5 (ig/L each for TCE and PCE throughout the
demonstration; (5) the system operates more efficiently at lower stripping tower pressures;
and (6) the 1,000-gallons per minute system at Lockheed has an estimated capital cost of
$4.3 million and annual operating and maintenance costs of approximately $820,000.
IV
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Contents
Page
Foreword iii
Abstract iv
Abbreviations and Symbols viii
Conversions x
Acknowledgements xi
1 Executive Summary 1
Introduction 1
Demonstration Results 1
Economics 2
Field Reliability 2
Conclusions 2
2 Introduction 5
Purpose, History, and Goals of the SITE Program 5
Documentation of the SITE Demonstration Results 6
Purpose of the Applications Analysis Report 6
Technology Description 6
3 Technology Applications Analysis 11
Technology Evaluation 11
Site Factors 14
Materials Handling 15
Personnel Requirements 16
Potential Community Exposures 16
Appropriate Waste and Site Conditions 16
Regulatory Requirements 17
4 Economic Analysis 21
Introduction 21
Basis of Economic Analysis 21
Site-Specific Factors Affecting Cost 21
Cost Categories 22
References 27
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Contents (continued)
Page
Appendices 29
A. Key Contacts for the SITE Demonstration 29
AWD Technologies 31
EPA Regional Office 31
SITE Project Managers 31
The SITE Program 31
B. Vendor's Claims for the Technology 33
Introduction 36
The Technologies 36
System Advantages 38
The Project 39
Operating Costs 40
References 41
C. SITE Demonstration Results 43
Introduction 46
Site Characteristics 46
Treatment System Performance 47
Review of Treatment Results 50
References 54
D. Case Studies 55
Introduction 57
Case Study D-l, In-Situ Soil Vapor Extraction System, Northern
California 57
Case Study D-2, AquaDetox® Groundwater Treatment, Southern
California 58
Case Study D-3, AquaDetox® Vacuum Steam Stripping System,
King of Prussia, Pennsylvania 58
Case Study D-4, AquaDetox® Technology, Kalkaska, Michigan 59
Case Study D-5, Integrated Aquadetox®/SVE Treatment System,
Burbank, California 59
VI
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Figures
Number Page
2-1 Isometric View of the AWD Integrated AquaDetox®/SVE System 7
2-2 AWD Integrated AquaDetox®/SVE System Schematic 8
3-1 Tower Pressure vs. Steam/Groundwater Flow Rate Ratios
for all Test Runs 14
Tables
3-1 Federal and State ARARs for the AquaDetox®/SVE Process 18
4-1 Estimated Costs Associated with Moderate Vacuum
AquaDetox®/SVE Systems 22
vn
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Abbreviations and Symbols
Hg/L Micrograms per liter
AAR Applications Analysis Report
ARAR Applicable or Relevant and Appropriate Requirements
CERCLA Comprehensive Environmental Response Compensation and Liability
Act
CERI Center for Environmental Research Information
CFR Code of Federal Regulations
cm/sec Centimeters per second
CWA Clean Water Act
EPA U.S. Environmental Protection Agency
GAC Granular activated carbon
gpm Gallon per minute
HSWA Hazardous Solid Waste Amendments
kW Kilowatt
kWh Kilowatt hour
LADWP Los Angeles Department of Water and Power
LASC Lockheed Aeronautical Systems Company
Ib/hr Pounds per hour
MCL Maximum contaminant level
mg/L Milligrams per liter
mm Hg Millimeters of mercury
NCP National Contingency Plan
NIOSH National Institute for Occupational Safety and Health
NPDES National Pollutant Discharge Elimination System
NTIS National Technical Information Service
O&M Operation and maintenance
ORD Office of Research and Development
OSHA Occupational Safety and Health Act
OSWER Office of Solid Waste and Emergency Response
PCB Polychlorinated biphenyl
via
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Abbreviations and Symbols (continued)
PCE Tetrachloroethylene
POTW Publicly-owned treatment works
ppb Parts per billion
ppm Parts per million
PSD Public Service Department
QA/QC Quality assurance/quality control
RCRA Resource Conservation and Recovery Act
RWQCB Regional Water Quality Control Board
SARA Superfund Amendments and Reauthorization Act
scfm Standard cubic feet per minute
SDWA Safe Drinking Water Act
SFVGB San Fernando Valley Groundwater Basin
SITE Superfund Innovative Technology Evaluation
SVE Soil vapor extraction
SVOC Semi-volatile organic compound
TCE Trichloroethylene
TDS Total dissolved solids
TER Technology Evaluation Report
TOC Total organic carbon
UCL Upper confidence limit
VOC Volatile organic compound
IX
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Conversions
Area:
Flow Rate:
Length:
Mass:
Temperature:
Volume:
English (US)
1ft2
1 gpm
1 scfm
1 Ib/hr
1ft
lin
lib
1 °F
1ft3
1 gallon
1 std ft3 of gas
Metric (SI)
9.2903 x lO-2 m2
2.2712 x ID-' mVhr
1.6957 std mVhr
4.5359 x 10-' kg/hr
0.3048 m
2.54 cm
4.5359 x 10 ' kg
5/9 (°F + 459.67) K
2.8317 x 10 2m3
3.7854 x 103 m3
2.S262 x 10-2 std m3
°F = degrees Fahrenheit
cm = centimeter
ft = foot, ft2 = square foot, ft3 = cubic foot
gpm = gallon per minute
in = inch
K = Kelvin
kg = kilogram, kg/hr = kilogram per hour
Ib = pound, Ib/hr = pounds per hour
m = meter, m2 = square meter, m3 = cubic meter
mVhr = cubic meter per hour
scfm = standard cubic feet per minute
std = standard conditions of 15.0°C and 101.325 kilopascal absolute
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Acknowledgements
This report was prepared under the direction and coordination of Ms. Norma Lewis and Mr.
Gordon Evans, U.S. Environmental Protection Agency's (EPA) Superfund Innovative
Technology Evaluation (SITE) Project Managers in the Risk Reduction Engineering
Laboratory, Cincinnati, Ohio. Mr. Chuck Biagi of AWD Technologies and Mr. David
Jensen of Lockheed Engineering and Sciences Company contributed greatly to this report.
Many other individuals reviewed and provided constructive comments to improve this
document. Lockheed Aeronautical Systems Company is greatly appreciated for allowing
the use of its site and treatment facilities and its assistance and cooperation throughout the
SITE demonstration.
Dr. Gary Welshans, Mr. Behzad Behtash, Mr. Kent Morey, and Ms. Barbara Sootkoos of
PRC Environmental Management, Inc., prepared this report for EPA's SITE Program under
Contract No. 68-CO-0047. Engineering-Science, Inc., performed the sampling and analytical
activities for this SITE demonstration.
XI
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Section 1
Executive Summary
Introduction
The integrated AquaDetox®/SVE technology developed
by AWD Technologies, Inc., was evaluated under the
U.S. Environmental Protection Agency's (EPA)
Superfund Innovative Technology Evaluation (SITE)
program. The first field-scale system has been
remediating volatile organic compound (VOC)
contamination at the Lockheed Aeronautical Systems
Company (LASC) at the San Fernando Valley Superfund
Site, Area I (Burbank/North Hollywood Well Field) in
Burbank, California since September 1988 and was the
subject of the SITE technology demonstration. The
demonstration was performed over a 2-week period in
September 1990.
The AWD technology simultaneously treats groundwater
and soil-gas contaminated with VOCs, such as
trichloroethylene (TCE) and tetrachloroethylene (PCE).
This technology integrates two basic processes: (1) a
high-efficiency, moderate vacuum stripping tower (tower
pressure no less than 50 mm Hg) that uses low-pressure
steam to treat contaminated groundwater and (2) a soil
vapor extraction (SVE) system that removes
contaminated soil-gas for subsequent treatment with
granular activated carbon (GAC). Integrating the two
technologies creates a closed-loop system, providing
simultaneous remediation of contaminated groundwater
and soil-gas with virtually no air emissions.
The AWD technology demonstration had the following
primary objectives:
• Evaluate the ability of the AWD integrated
AquaDetox®/SVE system to remove the VOCs
present in the contaminated groundwater and soil-
gas at the Lockheed site at AWD-specified operating
parameters.
• Evaluate the performance of the AWD system and
its percent removal efficiencies for VOCs under
varying operating conditions.
• Monitor the compliance of the AWD system with
regulatory discharge requirements.
• Develop capital and operating costs for the system.
• Identify specific operating and maintenance
concerns that may affect the long-term reliability of
the system.
This report presents the findings of the AWD technology
demonstration. The results and discussions presented in
this report can be used to evaluate possible
implementation of the AWD technology at other
Superfund or Resource Conservation and Recovery Act
(RCRA) Corrective Action sites. A detailed description
of the technology is presented in Section 2 of the report.
AWD technology's performance, requirements
(operation and maintenance, site conditions, and
personnel), and its applicability are discussed in Section
3. Section 4 presents an economic analysis of the
system.
Demonstration Results
The SITE demonstration consisted of 21 test runs under
varying operating conditions. The operating parameters
that were varied during the demonstration were: (1)
groundwater flow rate, (2) steam flow rate, (3)
AquaDetox® stripping tower pressure, and (4) GAC bed
regeneration frequency. Influent and effluent
groundwater and soil-gas samples were collected during
each test run for subsequent analyses. Temperature,
flow rate, tower pressure, and pH were also measured
and recorded for each test run.
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The groundwater and soil at the Lockheed site were
contaminated with TCE and PCE. Concentrations in the
influent groundwater samples collected during the
demonstration typically ranged from 400 to 600 ng/L
for TCE and 2,000 to 2,500 \ig/L for PCE. Soil-gas
samples from the demonstration had concentrations of
approximately 10 parts per million (ppm) for TCE and
400 ppm for PCE. No other VOCs were detected in the
groundwater or soil-gas at the site.
Groundwater removal efficiencies for total VOCs (TCE
and PCE combined) ranged from 99.92 to 99.99 percent.
The removal efficiencies were slightly higher for PCE
than TCE. Soil-gas removal efficiencies ranged from
98.0 to 99.9 percent for total VOCs when the GAC beds
were regenerated in 8-hour shifts as specified by AWD.
As expected, removal efficiencies were lower (as low as
93.4 percent) when the GAC beds were regenerated less
frequently.
Ninety-five percent upper confidence limit (UCL) values
for effluent groundwater TCE and PCE concentrations
were compared with the regulatory discharge
requirement (5 [igfL for each compound) for all test runs.
Although the operating conditions in some test runs were
less than optimum, the effluent from all test runs met the
regulatory discharge requirement.
Economics
An economic analysis was performed that examined 12
separate cost categories for a moderate vacuum
AquaDetox®/SVE system. Three treatment flow rates
were evaluated: 500, 1,000, and 3,000 gallons per
minute (gpm). Based on the economic analysis, the
capital costs for the 500-, 1,000-, and 3,000-gpm systems
were calculated to be approximately $3.2, $4.3, and $6.0
million (1991 $), respectively. The total annual operation
and maintenance (O&M) costs are approximately
$510,000, $820,000, and $2,000,000 (1991$) for the
500-, 1,000-, and 3,000-gpm systems, respectively.
Section 4 of this report details the capital and O&M
costs and presents the assumptions used to arrive at these
estimates.
Field Reliability
Only one major operating problem was encountered
during the SITE demonstration. The system was
inoperable for approximately 4 days because of a broken
SVE blower. This was considered to be unusual as the
system has been operating successfully for over 2 years
at the Lockheed site. During this time period, the system
has been operational for 93 percent of the time, with 7
percent down time due to scheduled or nonscheduled
repairs.
In the past, the high alkalinity of the groundwater at the
Lockheed site had caused scaling problems in parts of
the treatment system. A sulfuric acid injection system
has been installed at the Lockheed site to control the
groundwater's pH and to eliminate the scaling problem.
Conclusions
Based on the analytical results and observations from
the AWD SITE demonstration, the following
conclusions were made about the technology's
effectiveness and cost.
• The AWD technology can successfully treat
groundwater and soil-gas contaminated with
VOCs.
• The efficiencies ranged from 99.92 to 99.99 percent
for removal of VOCs from contaminated
groundwater. VOC removal efficiencies for soil-
gas ranged from 98.0 to 99.9 percent when the GAC
beds were regenerated according to the AWD-
specified frequency (8-hour shifts). VOC removal
efficiencies dropped to as low as 93.4 percent when
the GAC beds were regenerated less frequently.
• The AWD technology produced effluent
groundwater that complied with regulatory discharge
requirements for TCE and PCE (5 |ig/L for each
compound) at the Lockheed site throughout the
SITE demonstration. In addition, routine sampling
by Lockheed has shown that the effluent
groundwater has been in compliance with the
regulatory requirements throughout the 2-year
operation of the system.
• The GAC beds effectively removed VOCs from
contaminated soil-gas even after 24 hours of
continuous operation without steam regeneration.
The SITE demonstration results indicate that the
GAC beds at the Lockheed site may be oversized for
the current soil-gas VOC concentrations.
• The AquaDetox® system proved highly effective in
removing VOCs such as TCE and PCE (boiling
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points up to about 120°C) from contaminated
groundwater. The system should also be effective
for less volatile organics (boiling points in excess of
200°C according to the developer). However,
because higher boiling point organics were not
present in the groundwater treated during the AWD
SITE demonstration, the system's effectiveness in
removing this type of contamination could not be
evaluated. Water containing such organics should
be subjected to a treatability study.
The system's steam consumption dropped with
decreasing tower pressures. During the
demonstration, the system proved more efficient at
lower operating tower pressures.
The system has been operating successfully for over
2 years at the Lockheed site. During this time
period, the system has been operational for 93
percent of the time, with 7 percent down time due to
scheduled or nonscheduled repairs.
The AWD system is estimated to cost approximately
$3.2, $4.3, and $6.0 million (1991$), for the 500-
, 1,000-, and 3,000-gpm systems, respectively. The
total annual operation and maintenance (O&M)
costs are approximately $510,000, $820,000, and
$2,000,000 (1991$) for the 500-, 1,000-, and 3,000-
gpm systems, respectively.
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Section 2
Introduction
This section provides background information about the
Superfund Innovative Technology Evaluation (SITE)
Program, discusses the purpose of this Applications
Analysis Report, and describes the AWD technology. A
list of key contacts who can provide additional
information is provided in Appendix A.
Purpose, History, and Goals of the
SITE Program
In response to the Superfund Amendments and
Reauthorization Act of 1986 (SARA), EPA's Office of
Research and Development (ORD) and Office of Solid
Waste and Emergency Response (OSWER) established
the SITE Program to accelerate the development,
demonstration, and use of new or innovative
technologies to clean up hazardous waste sites across the
country. The SITE Program consists of five component
programs: (1) Demonstration Program; (2) Emerging
Technologies Program; (3) Measurement and Monitoring
Technologies Development Program; (4) Innovative
Technologies Program; and (5) Technology Transfer
Program.
The primary purpose of the SITE Program is to enhance
the development of and to demonstrate innovative
technologies applicable to hazardous waste sites, and
thereby establish their commercial availability. Major
goals of the SITE Program are to:
• Identify and remove impediments to the
development and commercial use of alternative
technologies.
• Demonstrate promising innovative technologies in
order to establish reliable performance and cost
information for site characterization and cleanup
decision making.
• Develop procedures and policies that encourage the
selection of available alternative treatment remedies
at Superfund sites.
• Structure a development program that nurtures
emerging technologies.
EPA recognizes that a number of forces inhibit the
expanded use of alternative technologies at hazardous
waste sites. One of the objectives of the program is to
identify these impediments and remove them or design
methods to promote the expanded use of alternative
technologies.
Another objective of the SITE Program is to demonstrate
and evaluate selected technologies. This is a significant
ongoing effort involving ORD, OSWER, EPA Regions,
and the private sector. The demonstration program
serves to test field-ready technologies and provide
Superfund decision makers with the information
necessary to evaluate the use of these technologies for
future cleanup actions.
Another aspect of the SITE Program includes
developing procedures and policies that match available
technologies with wastes, media, and sites for actual
remediation.
The SITE Program also provides assistance in nurturing
the development of emerging innovative technologies
from the laboratory- or bench-scale to the pilot- or field-
scale stage.
Technologies chosen for a SITE demonstration must be
pilot- or full-scale applications, innovative, and offer
some advantage over existing technologies. Mobile
technologies are of particular interest.
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Documentation of the SITE
Demonstration Results
The results of each SITE demonstration are incorporated
into two documents: the Technology Evaluation Report
(TER) and the Applications Analysis Report (AAR).
The TER provides a comprehensive description of the
demonstration and its results. A likely audience for the
TER is engineers responsible for performing a detailed
evaluation of the technology for a specific site and waste
situation. These technical evaluators seek to understand,
in detail, the performance of the technology during the
demonstration and the advantages, risks, and costs of the
technology for the given application. This information
may be used to develop specific plans to test and
evaluate the demonstrated technology.
The AAR is intended for decision makers responsible
for implementing specific remedial actions. The basic
use of the AAR is to assist in determining whether the
specific technology should be considered further as an
option for a particular cleanup. The report discusses the
advantages, disadvantages, and limitations of the
technology. Costs of the technology for different
applications are estimated based on available data for
the operational system. The report discusses the factors,
such as site and waste characteristics, that have a major
impact on performance and cost. If the candidate
technology appears to meet the needs of the site
engineers, a more thorough analysis should be conducted
based on the TER, the AAR, and information from
remedial investigations for the specific site.
Purpose of the Applications Analysis
Report
To encourage the general use of demonstrated
technologies, EPA will evaluate the applicability of each
technology in regards to certain sites and wastes, other
than those already tested, and will study the likely costs
of these applications. The results are presented through
the AAR. These reports attempt to synthesize available
information on the technology and draw reasonable
conclusions as to its broad range applicability. The AAR
is very useful to those considering the technology for
Superfund cleanups and represents a critical step in the
development and commercialization of the treatment
technology.
Each SITE demonstration will evaluate the performance
of a technology in treating a particular waste found at the
demonstration site. To obtain data with broad
applications, attempts will be made to select waste
frequently found at other Superfund sites. In many
cases, however, the waste at other sites will differ in
some way from the waste tested. Thus, the successful
demonstration of a technology at one site does not
ensure that it will work equally well at other sites. Data
obtained from the demonstration may have to be
extrapolated to estimate the total operating range over
which the technology performs satisfactorily. This
extrapolation should be based upon both demonstration
data and other information available about the
technology.
The amount of available data for the evaluation of an
innovative technology varies widely. Data may be
limited to laboratory tests on synthetic wastes, or may
include performance data on actual wastes treated at
pilot- or field-scale treatment systems. In addition, there
are limits to conclusions regarding Superfund
applications that can be drawn from a single field
demonstration. A successful field demonstration does
not necessarily ensure that a technology will be widely
applicable or fully developed to a commercial scale.
Technology Description
The AWD technology simultaneously treats
groundwater and soil-gas contaminated with volatile
organic compounds (VOC), such as trichloroethylene
(TCE) and tetrachloroethylene (PCE). This technology
integrates two processes: (1) AquaDetox®, a moderate
vacuum steam stripping tower (tower pressure no less
than 50 mm Hg) that treats contaminated groundwater
and (2) a soil vapor extraction (SVE) system that
removes contaminated soil-gas for subsequent treatment
with granular activated carbon (GAC). The two
technologies are integrated into a closed-loop system,
providing simultaneous remediation of contaminated
groundwater and soil-gas with no air emissions. The
integrated AquaDetox®/SVE system is shown in Figure
2-1.
AquaDetox® is a high-efficiency, countercurrent
stripping technology developed by the Dow Chemical
Company. Stripping is commonly defined as a process
that removes dissolved volatile compounds from water.
A carrier gas, such as air or steam, is purged through the
contaminated water, with the volatile components being
transferred from the water into the gas phase. According
to the developer, the AquaDetox® technology can be
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RERUN WATER
TANK
CONTROL ROOM
AOUADETOX
STRIPPING TOWER
GRANULAR ACTIVATED
CARBON BEDS
CONTAINMENT
BERM
SOLVENT
STORAGE TANK
CONDENSER
VACUUM PUMP
GRA VITY SEPARA TOR
NOTE: SOURCE OF STEAM NOT SHOWN
Figure 2-1. Isometric View of the AWD Integrated AquaDetox / SVE System.
HEAT EXCHANGER
used to remove a wide variety of volatile compounds and
many compounds that are normally considered
"nonstrippable" (i.e., those with boiling points in excess
of 200°C). The application of AquaDetox® for the
removal of compounds with boiling points greater than
200°C and the use of vacuum are patented by the Dow
Chemical Company.
SVE is commonly used for the in-situ removal of VOCs
from soil. A vacuum is applied to vadose zone
extraction wells to induce airflow within the soil toward
the wells. The air acts as a stripping medium that
volatilizes the VOCs in the soil. Soil-gas from the
extraction wells is typically treated in GAC beds before
release to the atmosphere. Alternatively, the treated soil-
gas is reinjected into the soil to control the direction of
air flow in the soil.
The AquaDetox® and SVE systems are connected in a
closed loop. Noncondensable vapors from the
AquaDetox® system are combined with vapors from the
SVE compressor and treated using the GAC beds. The
GAC beds are regenerated periodically using steam.
This contaminated regeneration steam is then condensed
and sent to the AquaDetox® tower for treatment.
A schematic diagram of the integrated
AquaDetox®/SVE treatment system is shown in Figure
2-2. The demonstration system was designed to handle
1,200 gallons per minute (gpm) of groundwater and a
maximum of 300 standard cubic feet per minute (scfm)
of soil-gas. However, the system is normally operated
at a rate of 900 gpm groundwater and 170 scfm soil-
gas.
Groundwater Treatment System
The AquaDetox® stripping tower is a packed column
approximately 9 feet in diameter and 60 feet in height.
About 30 feet of the column are packed with plastic pall
rings. The tower operates at a pressure of approximately
105 mm Hg. Low-pressure steam supplied at a rate of
approximately 4,500 Ib/hr maintains the tower at a
temperature of 52°C.
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SOLVENT
STORAGE
TANK
///////////y/Y////
•OL-aUMJECnON WELLS H '// /////
y//A///A%ym.
OONTAUMATED OROUNDWATER
OROUNOWATER
EXTRACTION WELL
OROUNDWATER
RBNJECnONWEU.
Figure 2-2. AWD Integrated AquaDetox / SVE System Schematic.
Contaminated groundwater is pumped to the treatment
facility from an extraction well at an approximate depth
of 150 to 170 feet. The extracted groundwater enters the
facility at an approximate temperature of 18°C. This
relatively cool groundwater is used to condense the
stripping tower overheads and the steam used to
regenerate the GAC beds. It is also fed to a cross-
flow heat exchanger where it cools the treated
groundwaterexiting at the bottom of the tower from
approximately 52°C to 24°C. At the same time, the
untreated groundwater is heated from a temperature of
approximately 18°C to 48°C before entering the
AquaDetox® stripping tower. Less steam is required to
treat the groundwater at this higher inlet temperature.
As contaminated groundwater flows down the stripping
tower, it is heated to the tower's operating temperature
of 52°C by the injection of steam at the bottom of the
tower. Under these conditions of temperature and
reduced pressure, the VOCs are stripped from the
groundwater and exit the top of the stripping tower along
with the steam. The overhead stream flows to a water-
cooled condenser where it is condensed and pumped to
a gravity separator. The water for cooling the condenser
is provided by diverting a portion of the cool untreated
groundwater through the condenser and back to the main
influent groundwater stream.
Total condensation of the overhead stream is not
possible due to noncondensable gases present in the
stream. The uncondensed vapor stream from the first
condenser is sent to a secondary condenser where all but
trace quantities of the VOCs are condensed and pumped
to the gravity separator. The organic phase from the
gravity separator is pumped to and stored in a solvent
storage tank. The organics are periodically loaded from
the solvent storage tank into a truck for off-site
recycling. The aqueous phase from the gravity separator
is pumped to and stored in the rerun water tank where it
is recycled into the AquaDetox® stripping tower at a
low flow rate. The vent from the secondary condenser
contains all noncondensables and is sent to the GAC
beds for treatment before discharge into the reinjection
wells of the SVE system.
Soil Vapor Extraction System
Soil vapor is removed through extraction well clusters
at depths of approximately 150 feet and fed to a vapor-
liquid separator where excessive moisture is separated
from the vapor. The liquid collected in the vapor-
liquid separator is pumped to the rerun water tank for
treatment by the AquaDetox® stripping tower.
The vapor from the vapor-liquid separator is combined
-------
with the noncondensable vapors generated by the
AquaDetox® process. This combined stream is treated
by two GAC beds connected in series. The treated soil-
gas coming off the bottom of the second GAC bed is
reinjected into the soil at depths ranging from 50 to 150
feet through the vadose zone. The soil-gas then sweeps
horizontally through the contaminated soil, picking up
additional hydrocarbons, and is once again collected in
the soil-gas extraction well system, where hydrocarbons
are again removed.
A third GAC bed is regenerated while the other two
GAC beds are on-line. The GAC beds are regenerated
by injection of steam at the bottom of the beds. The
steam removes the VOCs and exits through the top of
the GAC beds. The contaminated steam is then
condensed and sent to the AquaDetox® stripping tower
for treatment. Once each 8 hours, the regenerated off-
line bed is placed in service and a spent GAC bed is
removed from service and regenerated.
Innovative Features of the Technology
Typical treatment options for VOC-contaminated
groundwater include air or steam stripping, carbon
adsorption, ultraviolet radiation/oxidation technologies,
and biological treatment. VOC-contaminated soil may
be treated by various technologies, including enhanced
aeration, vacuum extraction followed by carbon
adsorption, incineration, and biodegradation. An
innovative feature of the AquaDetox ®/SVE system is
its ability to treat the contaminated groundwater and soil-
gas simultaneously.
Steam stripping and SVE systems are widely used for
remediation of contaminated water and soil. The
technologies are well known. As such, neither
technology can justifiably be labeled "innovative."
However, AWD Technologies' integration of these two
technologies produces a system that treats contaminated
groundwater and soil simultaneously with no air
emissions.
While the AquaDetox® system extracts and treats
contaminated groundwater, an array of SVE wells
removes contaminated soil-gas from the vadose zone.
The soil-gas is treated by the carbon beds and reinjected
into the ground to sweep through the soil and remove
additional contamination. This integrated system
combines the advantages of both technologies while
eliminating many of the disadvantages that are normally
associated with each technology.
Particularly, the integrated AquaDetox®/SVE system
eliminates frequent GAC replacement and greatly
simplifies the GAC regeneration process. Typically,
GAC is used until it becomes saturated, at which time it
is physically replaced with new or regenerated GAC.
The costly physical removal and off-site regeneration of
GAC is unnecessary with the AWD technology.
The process of acquiring an air permit is also simplified
because the integrated AquaDetox®/SVE system was
designed to operated with no air emissions. As air
emission standards become stricter, AWD Technologies'
zero air emission advantage becomes increasingly
important.
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Section 3
Technology Applications Analysis
This section addresses the general applicability of the
AWD integrated AquaDetox®/SVE technology to
contaminated waste sites. The analysis is based
primarily on the SITE demonstration results. Limited
information about other applications of the technology is
also presented. The developer's claims regarding the
applicability and performance of the integrated
AquaDetox®/SVE technology are included in Appendix
B.
Technology Evaluation
The demonstration of the AWD integrated
AquaDetox®/SVE technology was designed to achieve
the following primary objectives:
• Evaluate the ability of the AWD integrated
AquaDetox®/SVE system in removing the volatile
organic compounds (VOC) present in the
contaminated groundwater and soil-gas at the
Lockheed site at AWD-specified operating
parameters.
• Evaluate the performance of the AWD system and
calculate its percent removal efficiencies for VOCs
under varying operating conditions.
• Monitor the compliance of the AWD system with
regulatory discharge requirements.
• Develop capital and operating costs for the system.
• Identify specific operating and maintenance
concerns that may affect the long-term reliability of
the system.
To achieve these objectives, a SITE Demonstration plan
was developed (PRC, 1990) outlining a test plan
consisting of 21 test runs. The demonstration was
completed in September 1990. Analytical tests were
performed on samples of untreated and treated waste
materials collected during the demonstration. The
results are summarized in Appendix C and are discussed
more thoroughly in the Technology Evaluation Report.
An overview of the demonstration and the effectiveness
of the AWD technology are discussed below.
Site Demonstration Overview
The SITE demonstration was conducted at the Lockheed
site in Burbank, California. The treatment system at this
site is a full-size unit capable of treating 1,200 gallons
per minute (gpm) of groundwater and 300 standard cubic
feet per minute (scfm) of soil-gas. The system began
operation in September 1988. The use of a full-size unit
for the SITE demonstration made system modifications,
such as the addition of sampling ports and flow meters
more difficult or impossible to achieve. In addition,
certain operating conditions were unattainable because
of the site-specific design of the system.
There were, however, advantages to using a full-size
system for the demonstration. A major advantage of
demonstrating a full-size system is that the results
achieved by the system at Lockheed are more likely to
be duplicated by other systems at similar sites. In
addition, demonstrating a full-size system eliminates
scale-up considerations. Finally, the nature of
operational problems encountered during this
demonstration should be indicative of what to expect at
other sites.
During the demonstration, the system treated
groundwater and soil-gas contaminated with VOCs. The
primary contaminants present at the Lockheed site were
trichloroethylene (TCE) and tetrachloroethylene (PCE)
in soil and groundwater. The effectiveness of the AWD
technology was evaluated by analyzing the soil-gas and
11
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groundwater samples that were collected for each test
run. The groundwater and recovered solvent samples
were analyzed for VOCs using EPA SW-846 Methods
8010, 8015, and 8020. The soil-gas samples were
analyzed for VOCs using NIOSH Methods 1003 and
1022. In addition, several groundwater samples were
analyzed for polychlorinated biphenyls (PCB) and semi-
volatile organic compounds (SVOC) using SW-846
Methods 8080 and 8270, respectively. Other
groundwater analysis included alkalinity, hardness, pH,
temperature, total organic carbon (TOC), and total
dissolved solids (TDS).
Effectiveness of the AWD Technology
The analytical results indicate that the AWD technology
effectively reduced the concentration of VOCs in the
treated groundwater and soil-gas. Groundwater removal
efficiencies of 99.92 percent or better were observed in
all test runs for TCE and PCE. In addition, the effluent
groundwater concentrations of TCE and PCE were
below the regulatory discharge limit of 5 \lg/L (each) for
all the test runs. Soil-gas removal efficiencies ranged
from 98.0 to 99.9 percent for total VOCs (TCE and PCE
combined) when the granular activated carbon (GAC)
beds were regenerated in 8-hour shifts as specified by
AWD. As expected, removal efficiencies were lower (as
low as 93.4 percent) when the GAC beds were
regenerated less frequently. Reinjected soil-gas was not
subject to regulatory requirements.
Factors Influencing Performance
Waste characteristics, operating conditions, maintenance
requirements, and other factors influencing the
performance of the AWD technology are discussed
below.
Waste Characteristics
The AquaDetox®/SVE system at Lockheed was
designed to handle influent groundwater VOC
concentrations of approximately 12,000 |ig/L and soil-
gas VOC concentrations of approximately 6,000 parts
per million (ppm). Significantly higher influent VOC
concentrations may produce effluent groundwater that
does not meet the regulatory discharge requirements;
however, the operating conditions of the system can be
modified to improve its overall removal efficiency at the
expense of higher operating costs. The developer claims
that systems can be designed to accommodate much
higher influent VOC concentrations than those
encountered at the Lockheed site. According to AWD
Technologies, the design of a system is not significantly
impacted until the influent VOC concentrations exceed
200,000 |ig/L.
Characteristics of Contaminated Groundwater
Characteristics of the organic contaminants also
influence removal efficiencies. The AquaDetox®
system is designed to treat organ ics with higher boiling
points than is possible with more traditional designs such
as nonvacuum air strippers. However, the boiling point
and vapor pressure of the organic contaminants do
influence the efficiency of the AWD technology.
Generally, organics with lower boiling points and higher
vapor pressures such as VOCs are more readily stripped
by the AquaDetox® system. However, the system is not
limited to VOCs. According to the developer, organics
with boiling points in excess of 200° C can be
successfully treated by the AWE* system.
Hardness, pH, and alkalinity of the influent groundwater
are also important characteristics. High alkalinity and
hardness can cause scaling problems in various parts of
the system. At the Lockheed site, the high alkalinity of
the influent groundwater (alkalinity range of 250 to 340
mg/L, as CaCO3) was causing scaling problems in the
heat exchanger, reducing the heat transfer efficiencies
and increasing steam consumption. A sulfuric acid
injection system was employed at Lockheed to control
the scaling problem.
Characteristics of Contaminated Soil
Low boiling points and high vapor pressures are also
desirable characteristics for organic contamination in
the soil. Organics with high vapor pressure, such as
TCE and PCE, are more readily removed from the soil
by the SVE system.
Physical characteristics of the contaminated soil must
be evaluated to determine if SVE is a feasible solution.
Grain size, moisture content, stratification, and air
permeability are the most important properties in this
regard. Significant differences are generally observed
in the air conductivity of the various strata. A
horizontally stratified soil is usually suitable for SVE.
Its relatively impermeable strata limits the rate of
vertical inflow from the ground surface and tends to
extend the applied vacuum horizontally to useful
12
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distances from the point of application.
SVE is best suited for highly permeable soils with a
large grain size and a low moisture content. However,
for soils with even moderate permeability (permeability
range of about 10-3 to 105 cm/sec), sufficient air flow for
removal of contaminants is possible. However, the
success of SVE in these soils may be more dependent on
the presence of conductive strata such as sand or gravel.
Typically, the soil-gas extraction rate should be
approximately 100 to 1,000 scfm at an applied vacuum
of 50 to 150 mm Hg.
There are few guidelines for optimal design, installation,
and operation of SVE systems. Especially lacking are
theoretical design equations that would define the limits
of the technology. Consequently, it may be beneficial to
install and operate a small-scale or partial system on a
short-term basis to determine if a full-scale system
should be installed. If a full-scale SVE system proves
feasible, data collected from the installation and
operation of a partial system can be used for designing
a full-scale system.
Operating Parameters
Operating parameters can be varied during the operation
to achieve desired treatment efficiencies. The operating
parameters that were varied during the SITE
demonstration were the groundwater flow rate, steam
flow rate, stripping tower pressure, and the regeneration
period of GAC beds. These are the basic operating
parameters for the AWD AquaDetox®/SVE technology.
In general, lower tower pressures increase the efficiency
of the AquaDetox® stripping tower, and reduce the
required steam flow rate. Figure 3-1 shows the
relationship between the stripping tower pressure and
required steam flow rate. Because the groundwater flow
rate was not constant for all test runs, the steam flow rate
is reported per unit groundwater flow rate.
As shown on Figure 3-1, there is a direct relationship
between the tower pressure and steam flow. During the
SITE demonstration, approximately 20 percent of the
steam consumption was used to strip contaminants, the
other 80 percent was used to raise the incoming water to
its boiling point of approximately 52° C at 105 mm Hg.
As the stripping tower pressure was reduced, the
operating tower temperature, corresponding to the
boiling point of water, was also reduced. For example,
at 75 mm Hg (Run 15), the tower temperature was
lowered to 46° C. The amount of steam required to bring
the temperature of the influent groundwater from 18°C
to this lower tower temperature was significantly less.
Since approximately 80 percent of the steam is used for
heating of the influent groundwater, a significant
reduction in steam used for heating lowers the overall
steam requirements substantially. Steam requirements
for Runs 1 (105 mm Hg) and 8 (160 mm Hg) were 27
and 70 percent higher, respectively, than Run 15
performed at 75 mm Hg. Lower tower pressures also
increase the ability to strip higher boiling point organics.
Operation at low stripping tower pressures are possible
by using a larger vacuum pump, reducing the
groundwater flow rates, or both. During the SITE
demonstration, the lower tower pressures (75 to 95 mm
Hg) could only be achieved when the groundwater flow
rate was reduced from 900 to 600 gpm because the
system was designed to operate at a pressure of 105 mm
Hg. A system designed with a larger vacuum pump
would allow operation at lower tower pressures without
requiring a reduction in the groundwater flow rate,
thereby reducing steam consumption and increasing the
system's overall efficiency. However, larger vacuum
pumps have higher capital costs and are more costly to
operate.
Tower pressures in the 75 to 85 mm Hg range seemed
most efficient; however, operation at these reduced
tower pressures was only possible when the groundwater
flow rates were also reduced. Replacing the existing
vacuum pump with a larger system would allow higher
groundwater flow rate operation at reduced stripping
tower pressures and would improve the system's
efficiency.
Maintenance Requirements
Regular maintenance by a field technician is required
for successful operation of the AquaDetox ®/SVE
system. The system at Lockheed has operated
successfully since September 1988. According to AWD
Technologies, the system has been operational for 93
percent of the time, with 7 percent down time due to
scheduled or nonscheduled repairs.
Routine maintenance for prevention of scaling should
include inspection of groundwater lines, heat exchangers
and condensers, and the stripping tower. Particularly
13
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180
150 -
•3120 -\
x
E
60 -
30 -
A Tower Pressure
• Steam/GW Ratio
I I I I
6.00
5.00
Q.
3
4.00 *
C
-3.00 £
-2.00 £
I
E
h 1.00
0.00
1 2 345 67 8 11 12 13 14 15 16 17 18 19 20 21
Test Run Number
Figure 3-1. Tower Pressure vs. Steam / Groundwater Flow Rate Ratios for all Test Runs.
important are the heat exchangers and condensers where
the operating efficiencies can be greatly reduced by
excessive scaling. Antiscaling agents such as sulfuric
acid minimize scaling. At the Lockheed site, sulfuric
acid is routinely injected into the influent groundwater
stream to control scaling.
To date, major equipment repairs at the Lockheed site
have included rebuilding of a blower and replacing the
seals for the water rerun pump. Generally, piping,
valves, fittings, pump seals, blowers, and control valves
should be routinely inspected and repaired as required.
In-line measurement instrumentation including resistor
temperature detectors, differential pressure transmitters,
turbine and magnetic flow meters for groundwater, and
gas stream flow meters should be maintained regularly.
Most of the measurement instruments at the Lockheed
plant required no field calibration. However, if required
by the manufacturer, calibration procedures outlined in
the owner's manual should be followed for each
instrument.
Site Factors
Site-specific factors have an impact on the application
of the AWD technology. These factors should be
considered before using this technology.
Space
The 1,000-gpm treatment system at the Lockheed site is
laid out in a 4,000-square-foot area (52 feet by 75 feet).
The equipment is placed on a concrete pad with a 2-
foot spill containment berm surrounding the facility. A
control room containing the computer equipment is
located outside the containment area.
Utilities for the system at Lockheed, including steam
and electricity, are supplied from existing services on or
adjacent to Lockheed property, [f these services are not
readily available at another site, additional space for
steam generating boilers and electrical systems will be
required.
14
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The number and placement of groundwater and soil-
gas extraction and reinjection wells are also site-
specific. The system at Lockheed has one groundwater
extraction and one groundwater reinjection well. Soil-
gas is extracted through seven extraction wells, in three
clusters, and reinjected to the vadose zone through a
series of five reinjection wells. The exact number and
placement of wells required for any system will depend
upon the system capacity, plume location, size, and
movement for groundwater wells; and, soil conditions
and contamination profile for the soil-gas wells.
Additional space is required for storage, parking, and
site access for removal of recovered contaminants.
Climate
Climatic conditions can affect the AWD system and may
require design modifications for extreme conditions.
During the September 1990 SITE demonstration at the
Lockheed site in Burbank, extremely hot conditions were
encountered. Mid-day temperatures were in the high 90s
to over 100°F range. Under these extreme conditions of
heat and direct sunlight on the AquaDetox® tower, the
normal operating pressure of 105 mm Hg (or lower) was
unattainable. A larger capacity vacuum pump should be
considered for systems that will be located in warmer
climates.
Utilities
Steam is required for the operation of the AquaDetox®
tower and regeneration of the GAC beds. The amount
of steam required depends on the system's capacity, as
well as the operating conditions. The AquaDetox®/SVE
system at Lockheed required a steam flow rate of 3,800
pounds per hour (Ibs/hr) at a groundwater flow rate of
900 gpm. Considerably less steam was used for
regeneration of the GAC beds. GAC bed regeneration
steam was supplied at a flow rate of approximately 340
Ibs/hr. Existing steam plants on Lockheed property
supplied the steam required for the system at the
Lockheed site. Systems at other sites may require on-
site steam generating boilers sized according to the
system's overall capacity.
The treatment system at Lockheed requires an electrical
source capable of supplying 88 kilowatts (kW).
Electrical consumption depends on the system's capacity
and operating conditions. If an on-site source is not
readily available, additional provisions may be required.
Services and Supplies
A number of services and supplies are required for the
AWD technology. Most of these services and supplies
can be obtained locally. A telephone connection is
required to contact emergency services and to provide
normal communications.
Replacement parts and calibration equipment may be
obtained locally or shipped from regional companies.
Other supplies such as tools and drums can also be
purchased locally.
A security fence may be necessary to protect the
equipment at night and to prevent access to the site by
unauthorized personnel. Also, the services of a
hazardous waste recycling company are required for
periodic removal of recovered contaminants from the
site.
Materials Handling
Material handling for the AquaDetox®/S VE technology,
including pretreatment requirements and residual
handling, are discussed below.
Pretreatment Requirements
Due to the high alkalinity of the influent groundwater at
the Lockheed site, antiscaling treatment of the influent
groundwater is required. The principal disadvantage of
scaling is the reduction in heat transfer efficiency of the
cross exchanger, resulting in greater steam consumption.
An antiscalant agent such as PT 110, which is an
aqueous polyelectrolyte complex with microbiological
control agents, may be added to the influent groundwater
to control scaling. At the Lockheed site, however,
persisting scaling problems required an alternative
solution. To resolve the scaling problem at Lockheed a
sulfuric acid injection system was installed to control pH
and reduce scaling.
In addition, sites with high total dissolved solids (TDS)
in the groundwater may require filtering of the influent
stream. Groundwater with a high TDS content can
reduce the stripping tower's efficiency.
15
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Residual Handling
Three types of residuals are generated by the
AquaDetox®/SVE system: (1) effluent groundwater;
(2) recovered organics; and (3) spent GAC. The treated
groundwater is disposed of off-site. Three off-site
disposal options are available: (1) surface water
discharge; (2) discharge to a publicly-owned treatment
works (POTW); or (3) reinjection back into the aquifer.
During the SITE demonstration, the treated groundwater
was discharged to a storm sewer system. Currently,
Lockheed is reinjecting the treated groundwater back
into the aquifer using a groundwater reinjection well.
The recovered organics are stored in an on-site storage
tank. Periodically, a licensed waste hauler removes the
organics for recycling or off-site treatment depending on
the nature of organics. The GAC at the Lockheed site
has not been replaced since the system became
operational in September 1988. It is estimated that GAC
replacement will not be necessary until after at least 3
years of operation.
Personnel Requirements
The entire AquaDetox®/SVE system is controlled by a
computer system housed inside a small control room
adjacent to the process equipment. Although fully
automatic operation of the system is possible using the
computer control system, a field technician is needed to
make control adjustments, check and maintain the
equipment, make routine repairs, and collect
groundwater samples.
At the Lockheed site, a full-time field technician
maintained and operated the facility during the initial
start-up period. After 6 months of operation, the field
technician's time requirement was reduced to 24 hours
per week. It is anticipated that the field technician will
be needed for about 16 hours per week for future
operation of the treatment facility.
The time requirements for a field technician are reduced
by the computerized and highly automated control of the
treatment system and the built-in safety features that
automatically shut down the system if the system
malfunctions or is not operating within pre-specified
parameters. For example, if a pump fails or the stripping
tower pressure exceeds an acceptable value determined
by AWD Technologies, the control system will then
automatically shut down the system. Alarm conditions
are logged by the computer and an automatic telephone
dialer will notify the field technician about the shut
down.
The operating personnel are subject to Occupational
Safety and Health Act (OSHA) regulations. Specific
health and safety issues will vary depending on the type
of contamination present at a site. Therefore, a site-
specific Health and Safety Plan should be prepared.
This plan should include the facility description, a list of
chemicals of concern and their concentrations, health
and safety zones, personnel protective clothing and
equipment, contaminant monitoring procedures, hospital
routes, and the personnel to contact in the event of an
emergency.
Potential Community Exposures
Contaminant emissions from the AWD technology are
minimal. The AquaDetox®/SVE system produces no air
emissions; therefore, no major potential for on-site
personnel or community exposure to airborne
contaminants is anticipated. The SITE demonstration
results also indicated that the AWD technology reduced
the concentrations of TCE and PCE in the effluent
groundwater to below the regulatory discharge
requirements for these compounds. In case of system
malfunction, all components of the system will shut off
automatically, leaving no threat to the community.
Appropriate Waste and Site Conditions
The suitability of the AWD technology for a hazardous
waste site depends on several factors that must be
evaluated before selection of a site remediation method.
The suitability of a site is determined through waste
treatability studies and measurement of physical
conditions at the site. An obvious requirement for any
candidate site for the AWD technology is VOC
contamination of both groundwater and soil, a relatively
common occurrence. A thorough site assessment should
include the following steps:
• Review previous studies of similar wastes.
• Determine conventional water quality parameters
and specific contaminants present in the
groundwater and soil at the site and perform
treatability testing on wastes from the site.
16
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• Identify potential pretreatment options to improve
the waste treatment process.
• Assess site conditions affecting the treatment of
waste and the disposal of the treated waste.
• Review health and safety requirements.
Regulatory Requirements
This subsection discusses the regulatory requirements
for the AquaDetox®/SVE system as they relate to
conducting a hazardous waste site remediation. A
discussion of potential applicable or relevant and
appropriate requirements (ARAR) for a given remedial
action using the AquaDetox®/SVE process is provided
in Table 3-1.
Comprehensive Environmental Response,
Compensation, and Liability Act
The Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) of 1980
authorizes the Federal government to respond to releases
or potential releases of any hazardous substance into the
environment, as well as to releases of pollutants or
contaminants that may present an imminent or
significant danger to public health and welfare or the
environment.
The Superfund Amendments and Reauthorization Act
of 1986 (SARA) amended CERCLA and directed EPA
to:
• Use remedial alternatives that permanently and
significantly reduce the volume, toxicity, or mobility
of hazardous substances, pollutants, or contaminants.
• Select remedial actions that protect human health
and the environment, are cost-effective, and involve
permanent solutions and alternative treatment or
resource recovery technologies to the maximum
extent practicable.
• Avoid off-site transport and disposal of untreated
hazardous substances or contaminated materials
when practicable treatment technologies exist
(Section 121 (b)).
As part of the requirements of CERCLA, EPA has
prepared the National Contingency Plan (NCP) to
address responses to releases of hazardous substances.
The NCP (codified in 40 CFR Part 300) delineates the
methods and criteria for determining the appropriate
extent of removal and cleanup for hazardous substance
contamination.
In general, there are two types of responses possible
under CERCLA: removal actions and remedial actions.
The AquaDetox®/SVE process can be part of either
response type. However, if the process is used only for
a removal action, it will be limited in the amount of time
and money spent to implement the response. Superfund-
financed removal actions cannot exceed 12 months in
duration or $2 million in cost in most cases (Section
104(c) (1)).
Remedial actions are governed by CERCLA as amended
by SARA. As stated above, these amendments promote
remedies that permanently reduce the volume, toxicity,
and mobility of hazardous substances, pollutants, or
contaminants. Section 121 (c), of CERCLA as amended
by SARA, requires EPA to review any remedial action
in which hazardous substances, pollutants, or
contaminants remain at the site.
ARARs dictate the degree of cleanup necessary at
CERCLA sites. Requirements for identifying ARARs
are codified in 40 CFR Section 300.400(g). On-site
remedial actions must comply with Federal or more
stringent state ARARs that are determined on a site by
site basis.
No Federal, state, or local permits are required for on-
site response actions conducted pursuant to CERCLA
Section 104. Thus the process would be exempt from
these permit requirements, if used as part of an "on-
site" response action (40 CFR Section 300.400(e)).
Resource Conservation and Recovery Act
RCRA, an amendment to the Solid Waste Disposal Act,
was passed in 1976 to address the problem of how to
safely manage and dispose of municipal and industrial
solid wastes. RCRA specifically addresses the
identification and management of hazardous wastes.
The Hazardous and Solid Waste Amendments of 1984
(HSWA) significantly expanded the scope and
requirements of RCRA. RCRA regulations concerning
hazardous waste identification and management are
specified in 40 CFR Parts 124, 260-272. EPA- and
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Table 3-1. Federal and State ARARs for the AquaDetox / SVE Process
Process Activity
ARAR
Description
Basis
Response
Waste identification
(untreated soil-gas
and groundwater)
Extraction of soil-gas
groundwater
Waste processing
Transportation of
recovered solvent for
further reclamation
Discharging treated
groundwater to storm
drain or POTW
On-site monitoring
and maintenance
activities
RCRA 40 CFR Part
261 or state
equivalent
RCRA 40 CFR Part
262 or state
equivalent
RCRA 40 CFR Parts
264 and 265 or state
equivalent
RCRA 40 CFR Part
262 or state
equivalent
RCRA 40 CFR Part
263 or state
equivalent
CWA 40 CFR Part
122 or state
equivalent
OSHA 29 CFR
Part 1910, Subpart I
or state equivalent
Identifying and
characterizing the waste
Standards applicable to
the generation of
hazardous waste
Standards applicable to
the treatment of
hazardous waste at
permitted and interim
status facilities
Manifest and labeling
requirements prior to
transporting
Transportation Standards
Discharge Standards
Personnel Protection
Standards
A requirement of RCRA prior to
managing and handling the
waste
Chemical and physical analysis
must be performed as well as
determining if the soil-gas or
groundwater was contaminated
with a listed hazardous waste
If contaminated soil-gas or
groundwater is determined to
be a hazardous waste and
is extracted for treatment, the
requirements for a hazardous
waste generator will be applicable
Treatment of hazardous waste
must be conducted in a manner
that meets the operating and
monitoring requirements
Obtain an EPA identification and
number
Solvents recovered from the
treatment of a listed hazardous
waste which require further
reclamation must be managed
as a hazardous waste
The recovered solvents must
be transported as hazardous
waste
Water discharged to a surface
water body must meet NPDES
permit standards and water
discharged to a POTW must
meet pretreatment standards
Personnel performing activities
on hazardous waste sites must
comply with OSHA
requirements
Previous testing indicates that
soil-gas and groundwater to be
treated is compatible with
the AquaDetox®/SVE process.
Equipment must be operated
and maintained daily.
EPA must issue an identification
number
A transporter licensed by EPA
must be used to transport the
hazardous waste according
to EPA regulations
Meet NPDES permit standards
or pretreatment standards
Wear personal protective
equipment such as Tyveks,
rubber gloves, and eye guards
RCRA-authorized states implement and enforce RCRA
and state regulations.
The key to determining whether RCRA regulations
apply to the AquaDetox®/SVE process is whether the
contaminated media is a hazardous waste. EPA defines
hazardous waste in 40 CFR Part 261. It is unlikely that
soil-gas will meet the statutory definition of a solid
waste; however, EPA has no specific policy on this
matter. If groundwater is contaminated with a listed
hazardous waste and extracted, the groundwater must be
treated as a hazardous waste.
If contaminated soil-gas or groundwater is determined to
be a hazardous waste, and is extracted for treatment,
storage, or disposal, the requirements for a hazardous
waste generator will be applicable. Requirements for
hazardous waste generators are specified in 40 CFR Part
262 and include obtaining an EPA identification number.
If hazardous wastes are treated by the AquaDetox®/SVE
process, the owner/operator of the treatment or disposal
facility must obtain an EPA identification number and a
RCRA permit from EPA- or RCRA-authorized state.
RCRA requirements for permits are specified in 40 CFR
Part 270. In addition to the permitting requirements,
18
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Part 270. In addition to the permitting requirements,
owners and operators of facilities which treat hazardous
waste must comply with 40 CFR Part 264.
Liquid organics recovered from the gravity separator
that are transported off-site for further reclamation will
be considered solid wastes and possibly considered
hazardous wastes. If the liquid organics are determined
to be hazardous wastes and must be stored on-site prior
to treatment, other RCRA regulations may apply. These
regulations may include complying with the use of a
Uniform Hazardous Waste Manifest, if hazardous waste
is transported off-site, complying with 90-day
accumulation limits for facilities without hazardous
waste storage permits (40 CFR Section 262.34),
complying with 40 CFR Part 264 or 265, Subpart I, if
hazardous wastes are stored in containers, and
complying with 40 CFR Part 264 or 265, Subpart J, if
hazardous wastes are stored in tanks.
Section 3020 of the RCRA statute allows the injection
of groundwater into the aquifer from which it was
withdrawn if the following requirements are met:
• The injection is a response taken under Section 104
or 106 of CERCLA, or part of a RCRA corrective
action;
• The contaminated groundwater is treated to
substantially reduce hazardous constituents prior to
such injection; and
• The response action or corrective action will, upon
completion, be sufficient to protect human health
and the environment.
Air emissions from hazardous waste treatment, storage,
or disposal operations are addressed in 40 CFR Part 264
and 265, Subparts A A and BB. The air emission
standards are applicable to treatment, storage, or disposal
units subject to the RCRA permitting requirements of 40
CFR Part 270 or hazardous waste recycling units that are
otherwise subject to the permitting requirements of 40
CFR Part 270.
RCRA Corrective Action
RCRA regulations (Sections 264.100 - 264.101) require
that a corrective action program be instituted as
necessary to protect human health and the environment
from all releases of hazardous waste or its constituents
from any solid waste management unit. The corrective
action program must be in compliance with groundwater
protection standards and must begin within a reasonable
amount of time after the groundwater protection
standard has been exceeded. The contaminated water
must be treated to the levels determined in the corrective
action order. These levels can vary, depending on state
and local requirements (e.g., National Pollutant
Discharge Elimination System (NPDES), POTW, or
maximum contaminant levels (MCL)).
Additionally, a groundwater monitoring program must
be implemented to prove that the corrective action
program has been effective. A corrective action must be
completed during the compliance period to the extent
necessary to ensure that the groundwater protection
standard is met. However, if a corrective action is not
completed within the compliance period, it must then
continue for as long as necessary to achieve compliance
with the groundwater protection standard.
Clean Water Act
The Clean Water Act (CWA), as amended by the Water
Quality Act of 1987, describes standards and
enforcement for discharges, including toxic and
pretreatment effluent standards which are applied
primarily to protect surface water quality. The CWA
established the NPDES, which requires that (1) EPA
publish water quality criteria for pollutants and (2) each
state set water quality standards, using the EPA criteria,
for every significant body of surface water within its
borders. States then issue permits for discharges into
these bodies of surface water.
NPDES requirements are specified in 40 CFR Part 122.
Part 122 requires that contaminated water be treated to
appropriate levels prior to discharging into a storm sewer
or surface water body. If the AquaDetox®/SVE process
is used as a RCRA corrective action and the treated
water is discharged to a surface water body, a NPDES
discharge permit would be required and pretreatment
standards (if discharged to a POTW) would need to be
identified.
Safe Drinking Water Act
The Safe Drinking Water Act (SOWA) of 1974, as most
recently amended by the Safe Drinking Water
Amendments of 1986, requires EPA to establish
regulations to protect human health from contaminants
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in drinking water. The legislation authorized national
drinking water standards and a joint Federal-state system
for ensuring compliance with these standards.
The National Primary Drinking Water Standards are
found in 40 CFR Parts 141 through 149. Wells used by
operators of hazardous waste management facilities to
dispose of hazardous waste into a formation within a
quarter-mile of an underground source of drinking water
will be classified as Class IV wells (Section 144.6 (d)).
Operators considering using wells to reinject
contaminated groundwater that has been treated and is
being reinjected into the same formation from which it
was drawn are not prohibited from constructing and
operating Class IV wells if such injection is approved by
EPA for cleanup of releases under CERCLA or RCRA
corrective actions (Section 144.13 (c)).
Occupational Safety and Health Act
Superfund remedial actions and RCRA corrective
actions must be performed in accordance with the OSHA
requirements codified in 29 CFR Parts 1900 through
1926.
Although the AquaDetox®/S VE system requires limited
personnel involvement once it is operating under desired
conditions, technicians performing monitoring and
sampling must wear personal protective equipment, such
as rubber gloves and eye guards (Part 1910, Subpart I).
Additional personal protective equipment may be needed
when handling untreated groundwater. In addition, all
personnel working on-site must have completed 40
hours of formal health and safety training in accordance
with 29 CFR 1910.120(e). A medical surveillance
program in accordance with 29 CFR 1910.120(f) should
also be instituted.
State occupational safety and health requirements may
be significantly stricter than Federal standards.
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Section 4
Economic Analysis
Introduction
The costs associated with the AWD AquaDetox®/SVE
system can be separated into 12 cost categories that
reflect typical cleanup activities at Superfund and
RCRA-corrective action sites. These categories include
site preparation costs; permitting and regulatory costs;
capital and equipment costs; startup and fixed costs;
labor costs; supply and consumable costs; utility costs;
costs for effluent disposal to a municipal system;
residuals and waste shipping, handling, and
transportation costs; analytical costs; equipment repair
and replacement costs; and site demobilization costs.
The estimated cost analysis presented in Table 4-1 is
based on the discussions of each cost category included
in this section.
Basis of Economic Analysis
This economic analysis is based on the costs associated
with the 1,000-gallons per minute (gpm), moderate
vacuum AquaDetox®/SVE system operating at the
Lockheed site. The cost data for the 500- and 3,000-
gpm systems were provided by Lockheed and AWD
Technologies, or were extrapolated from the cost data for
the 1,000-gpm system. One-time costs as well as annual
operation and maintenance (O&M) costs for these
systems are presented in Table 4-1. These costs are
order-of-magnitude (-30 to +50 percent) estimates, as
defined by the American Association of Cost Engineers,
and are based on 1991 costs.
This analysis assumes that the moderate vacuum system
will be operated continuously, 24 hours a day, 7 days a
week, for 1 year. During this 1-year period, the
moderate vacuum system would treat 0.26 billion gallons
for a 500-gpm system; 0.52 billion gallons for a 1,000-
gpm system; and 1.6 billion gallons for a 3,000-
gpm system. One year was chosen as the period of time
for this analysis so that annual operating and
maintenance costs could be determined. However, it
should be noted that most groundwater remedial actions
require a greater amount of time (e.g., 5 to 30 years).
The following two operating conditions were assumed:
(1) vacuum pressure of 105 mm Hg within the steam
stripping tower and (2) low pressure steam supplied at
4,500 Ibs/hour to maintain the tower temperature at
52°C. Furthermore, this analysis assumes that the
groundwater is contaminated only with VOCs, primarily
TCE and PCE. The total VOC contaminant
concentration is assumed to be approximately 12,000
Hg/L, of which the concentrations of TCE and PCE
combined comprise 11,000 Hg/L. These contaminant
levels are similar to those initially observed at the
Lockheed site.
Site-Specific Factors Affecting Cost
Several major factors affecting the cost of the AWD
system are highly site-specific. The site-specific factors
most affecting the cost include the following: volume of
contaminated groundwater and soil-gas to be treated;
extent of contamination; site preparation requirements
(i.e., length of access roads to be constructed and amount
of regrading required for the treatment pad); extraction
and reinjection wells required (i.e., number and type);
and treatment goals.
The costs presented in this analysis are based on
conditions found at the Lockheed site. Any assumptions
made regarding site-specific costs are included in the
discussions for each cost category. Site-specific costs
for the AWD system are difficult to estimate since data
from other remedial actions using the system are not
available and, therefore, cannot be used to compare
results and findings.
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Table 4-1. Estimated Costs Associated with Moderate Vacuum AquaDetox®/ SVE Systems
Estimated Costs (1991 $)
Item
500-gpm
• One-time costs.
"Annual operation and maintenance costs.
1,000-gpm
3,000-gpm
Site Preparation Costs*
Permitting and Regulatory Costs*
Capital Equipment Costs*
Startup and Fixed Costs*
Labor Costs6
Supply and Consumable Costs"
Utility Costs"
Effluent Disposal Costs (Municipal System)"
Residuals and Waste Shipping, Handling, and Transportation Costs"
Analytical Costs"
Equipment Repair and Replacement Costs"
Site Demobilization Costs*
Total One-Time Costs
Total Annual O&M Costs
650,000
90,000
1,800,000
110,000
71,000
53,000
165,000
160,000
0
21,000
41,000
500.000
3,150,000
511,000
930,000
130,000
2,600,000
121,000
71,000
73,000
279,000
320,000
0
21,000
58,000
500.000
4,281,000
822,000
1,350,000
190,000
3,800,000
161,000
110,000
96,000
734,000
960,000
0
21,000
76,000
500.000
6,001,000
1,997,000
Cost Categories
The items and assumptions associated with each of the
12 cost categories in Table 4-1 are discussed in the
following subsections.
Site Preparation Costs
Site preparation costs can be divided into planning and
surface preparation costs for the treatment system.
Planning costs include the engineering, administrative,
and construction management costs involved with
system design and construction. Planning costs for the
system are approximately 35 percent of capital
equipment costs (10 percent for engineering, 15 percent
for administrative, and 10 percent for construction
management), or $630,000 for the 500-gpm system,
$910,000 for the 1,000-gpm system, and $1,330,000 for
the 3,000-gpm system.
Surface preparation costs can vary greatly depending on
the type of site where the treatment operation takes
place, the condition of the site, and the size of the
treatment system. This analysis assumes that the
treatment system and support facilities for each unit
cover an approximately 10,000 square-foot area. Sites
that require major clearing and regrading for the
foundation will significantly increase site preparation
costs. In addition, some sites may require the
construction of access roads. This analysis assumes that
surface preparation costs include temporary trailer rental,
minor clearing of the site, and installation of emergency
and safety equipment ($3,400); surface grading
($0.08/square foot); construction of a 1-foot thick
concrete foundation for the system ($0.57/square foot);
and fencing ($12.50/linear foot) (Means, 1990). Surface
preparation costs, therefore, are approximately $20,000,
including a 20 percent contingency.
Based on these assumptions, site preparation costs are
approximately $650,000 for the 500-gpm system,
$930,000 for the 1,000-gpm system, and $1,350,000 for
the 3,000-gpm system.
Permitting and Regulatory Costs
Permitting and regulatory costs can vary depending on
whether treatment is performed at a Superfund or
RCRA-corrective action site. At Superfund sites,
Section 121 (d) of CERCLA as amended by SARA
requires that remedial actions be consistent with any
applicable or relevant and appropriate requirements
(ARAR). For the AquaDetox®/SVE system, ARARs
will affect the treatment goals set to meet discharge or
reinjection requirements. At RCRA-corrective action
sites, regulatory costs will increase since analytical
protocols and monitoring reports need to be maintained
during operation of the treatment system.
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Permitting and regulatory costs will also vary depending
on how the effluent is disposed. Permits are required for
any discharges to publicly-owned treatment works
(POTW) or any surface water bodies. Such permits may
require additional effluent monitoring prior to discharge.
This analysis assumes that treatment is being conducted
as part of a Superfund remedial action and that the
effluent is discharged to a POTW. Permitting and
regulatory costs are assumed to be approximately 5
percent of the capital equipment costs, or $90,000 for the
500-gpm system, $130,000 for the 1,000-gpm system,
and $190,000 for the 3,000-gpm system.
Capital Equipment Costs
Capital equipment costs are one-time costs associated
with purchasing and installing the treatment system on-
site. These costs include purchasing and installing the
following components of the system: an AquaDetox®
vacuum stripping tower; a soil-gas vapor
extraction/reinjection system; a three-bed granular
activated carbon (GAC) unit; a control building; and,
associated piping, pumps, blowers, heat exchanger,
condensers, filters, separators, and aboveground tanks.
In addition, the installation of one groundwater
extraction well is included as part of capital costs. If an
existing steam source is not available, cost of steam
generating boilers need to be added to the capital costs.
This analysis assumes that for a 1,000-gpm moderate
vacuum system, one groundwater extraction well and
eight vapor extraction/reinjection wells will be installed
at a total cost of $200,000. This cost is based on
information provided by AWD and conditions at the
Lockheed site, where (1) the contaminated aquifer is
located 150 to 170 feet below ground surface and (2) all
extraction and reinjection wells are located within 1,000
feet of the treatment plant. It should be noted that since
the number of groundwater and vapor
extraction/injection wells required for effective operation
of the system is highly site-specific, costs for well
installation will vary greatly from site-to-site. For the
500- and 3,000-gpm systems, well installation costs are
estimated at $100,000 and $600,000, respectively.
Any contaminated soil removed during the installation
of extraction and reinjection wells that is hazardous will
need to be stored in compliance with RCRA and state
requirements. Soil disposed of at a permitted landfill
will have to be treated to meet Federal or state land
disposal restriction requirements. Since hazardous waste
disposal costs vary greatly depending on the type and
level of contamination, as well as site location, this
analysis assumes that hazardous soil is not generated
during well installation.
Major components of the treatment system include the
AquaDetox® tower and packing material, control room,
computerized control system, GAC beds, and various
process components including tanks, separators,
condensers, pumps, piping, measurement instruments,
and control valves. Capital equipment costs also include
the initial utility connections required for the treatment
system. For the SITE demonstration, only a new
electrical connection was required; steam and electrical
service were available from the Lockheed site. Utility
connections can be either overhead or buried; however,
buried utility connections typically require more design,
planning, and construction. For this analysis, it is
assumed that utility connections are overhead.
Based on these assumptions and on information
provided by AWD, total capital costs are $1.8 million
for the 500-gpm system; $2.6 million for the 1,000-
gpm system; and $3.8 million for the 3,000-gpm
system.
Startup and Fixed Costs
Startup and fixed costs include those required to
mobilize equipment, perform an initial shakedown of
the equipment, establish operating procedures, train
operators, and perform health and safety monitoring.
Mobilization and shakedown costs include transporting
the unit to the site, performing an initial on-site checkout
of the equipment, and evaluating the system's
performance to determine the proper operating
parameters for treatment. These costs are highly site-
specific. For this analysis, mobilization and shakedown
costs (including a 20 percent contingency) are assumed
to be $100,000 for the 500-gpm system, $110,000 for
the 1,000-gpm system, and $150,000 for the 3,000-
gpm system.
To ensure safe, economical, and efficient operation of
the system, a program to train operators is necessary.
Training will include instruction on operating and
maintaining the system as well as health and safety
measures. This training will be given to one individual
(i.e., a field technician) responsible for monitoring the
system. This analysis assumes that AWD personnel will
23
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instruct the field technician for 1 week in the operation
and maintenance of the system, and that the field
technician will attend a 40-hour health and safety
training course. Training costs for all systems are
estimated to be approximately $11,000, including a 20
percent contingency.
Based on these assumptions, total startup and fixed costs
for each system are assumed to be approximately
$110,000 for the 500-gpm system, $121,000 for the
1,000-gpm system, and $161,000 for the 3,000-gpm
system.
Labor Costs
Once the AWD AquaDetox®/SVE system is installed
and shakedown is completed, the system requires very
little labor for operation. One field technician will be
needed to check and maintain the equipment, make
routine repairs, and take water samples. Based on
information provided by AWD and from case studies,
this analysis assumes that for the 500- and 1,000-gpm
systems, the technician would be needed for 16 hours a
week, and for the 3,000-gpm system, the technician
would be needed for 32 hours a week. These estimates
do not include labor costs associated with major
equipment repairs.
For the 500- and 1,000-gpm systems, the annual labor
costs are estimated at $71,000. For the 3,000-gpm
system, the annual labor costs are estimated at $ 110,000.
The labor rates used in this analysis include indirect
costs on labor such as benefits.
Supply and Consumable Costs
Supplies and consumables for the moderate vacuum
systems include sulfuric acid to maintain pH and
miscellaneous maintenance supplies such as oil and
antiscalant chemicals. The volume of sulfuric acid used
depends on the pH level and alkalinity of the
contaminated water and the size of the system employed.
The system at Lockheed requires about 70 gallons of 96
percent sulfuric acid solution per day at a cost of
approximately $1 per gallon. The quantities of
miscellaneous supplies used depend on the type and size
of the system employed.
Based on current operating information provided by
Lockheed, the annual costs for sulfuric acid and
miscellaneous maintenance supplies are estimated at
$53,000 for the 500-gpm system, $73,000 for the 1,000-
gpm system, and $96,000 for the 3,000-gpm system.
Utility Costs
Utility costs include the amount of electricity needed to
operate the AquaDetox®/SVE system. The AWD
system runs on electricity from a local utility. Based on
current operating information provided by Lockheed,
which assumes a cost of $0.07/kWh, annual electrical
costs are $42,000 for the 500-gprn system, $54,000 for
the 1,000-gpm system, and $84,000 for the 3,000-
gpm system.
Utility costs also include steam. Based on information
provided by Lockheed, which assumes a cost of
$5.70/1,000 pounds steam, the average annual costs for
steam are assumed to be $123,000 for the 500-gpm
system, $225,000 for the 1,000-gpm system, and
$650,000 for the 3,000-gpm system.
For this analysis, utility costs do not include any costs
associated with installing and maintaining a telephone
line.
Total utility costs, therefore, are $165,000 for the 500-
gpm system, $279,000 for the 1,000-gpm system, and
$734,000 for the 3,000-gpm system.
Effluent Disposal Costs
Effluent disposal costs will vary significantly based on
the type and amount of contaminants discharged. This
analysis assumes that effluent will be discharged to a
storm sewer system. The cost for effluent discharge to
a storm sewer system at the Lockheed site is
approximately $0.605 per 1,000 gallons. For the
AquaDetox®/SVE system, effluent can also be
reinjected into aquifers underlying the site, eliminating
the effluent discharge costs; however, reinjection is also
subject to stringent monitoring requirements.
This analysis also assumes that effluent monitoring will
be performed routinely by a technician in accordance
with requirements of the discharge permit. Costs for the
technician to perform monitoring are included under the
labor cost category, and costs for analyzing effluent
samples are included in the analytical cost category.
Based on the costs associated with discharging effluent
at the Lockheed site, annual effluent disposal costs are
approximately $160,000 for the 500-gpm system,
24
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$320,000 for a 1,000-gpm system, and $960,000 fora
3,000-gpm system.
Residuals and Waste Shipping, Handling, and
Transportation Costs
The residuals and waste associated with the AWD
system include recovered organics, that can either be
disposed of or recycled, and spent GAC, that may need
replacement after approximately 3 years of operation.
The costs or credits associated with removal of the
recovered organics are highly site-specific. This analysis
assumes that the organics disposal or recovery costs are
negligible. In addition, GAC replacement costs are not
included in this analysis since the exact required
frequency of GAC replacement is yet to be determined.
Analytical Costs
Analytical costs include laboratory analyses, data
reduction and tabulation, quality assurance/quality
control (QA/QC), and reporting. This analysis assumes
that one effluent sample will be collected and analyzed
for organics each month. Monthly laboratory analyses
are estimated at approximately $1,250, while data
reduction and tabulation, QA/QC, and reporting are
estimated at approximately $500 per month. Total
annual analytical costs, therefore, are estimated at
$21,000 per year.
Equipment Repair and Replacement Costs
Equipment parts that may require repair and replacement
include motors, seals, gauges, regulators, gaskets, filters,
and the GAC beds. Based on information provided by
AWD, the annual costs for equipment repair and
replacement are estimated at $41,000 for the 500-gpm
system, $58,000 for the 1,000-gpm system, and $76,000
for the 3,000-gpm system. This corresponds to
approximately 2 percent of capital costs for each system.
Site Demobilization Costs
Site demobilization will include operation shutdown,
site cleanup and restoration, permanent storage costs,
and site security. Site demobilization costs will vary
depending on whether the treatment operation occurs at
a RCRA-corrective action site or a Superfund site.
Demobilization at a RCRA-corrective action site
requires detailed closure and post-closure plans and
permits. Demobilization at a Superfund site will not
require extensive post-closure care; for example, 30-
year monitoring is not required.
This analysis assumes that site demobilization costs
include decommissioning the equipment and
transporting it off-site. Costs for preparing closure plans
and conducting post-closure monitoring are not
included. In addition, this analysis assumes that the
equipment has no salvage value. According to AWD
Technologies, site demobilization costs do not vary
significantly for systems with capacities in the 500-
to 3,000-gpm range and are assumed to be $500,000 for
each system.
25
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References
AWD Technologies, Inc., 1989. AquaDetox® Stripping
System for Groundwater Remediation. AWD
Technologies, 1988.
AWD Technologies, Inc., 1989. Use of Vapor
Extraction Systems for In Situ Removal of Volatile
Organic Compounds from Soil. AWD
Technologies, 1988.
Environmental Protection Agency, 1988. Guidance on
Remedial Actions for Contaminated Groundwater at
Superfund Sites. U.S. EPA/540/G-88/003,
December 1988.
Environmental Protection Agency, 1990a. Handbook
on In Situ Treatment of Hazardous Waste-
Contaminated Soils. U.S. EPA, RREL, Cincinnati,
Ohio, EPA/540/2-90/002, January 1990.
Environmental Protection Agency, 1990b. State of
Technology Review: Soil Vapor Extraction
Systems. U.S. EPA, RREL, Cincinnati, Ohio,
EPA/600/S2-89/024, January 1990.
McCabe, W.L., J.C. Smith, and P. Harriott, 1985. Unit
Operations of Chemical Engineering, Fourth
Edition. McGraw-Hill Book Company.
Means, 1990. Building Construction Cost Data, Western
Edition. R.S. Means Company, Inc., 1990.
Perry, R.H., D.W. Green, and J.O. Malony, 1984.
Perry's Chemical Engineers' Handbook, Sixth
Edition. McGraw-Hill Book Company.
PRC Environmental Management, Inc., 1990.
Demonstration Plan for the AWD Technologies
Integrated AquaDetox®/SVE Technology. Prepared
for U.S. EPA, RREL, Cincinnati, Ohio, by PRC
SITE Team, September 1990.
Smith, J.M., and H.C. Van Ness, 1987. Introduction to
Chemical Engineering Thermodynamics, Fourth
Edition. McGraw-Hill Book Company.
Treybal, R.E., 1980. Mass-Transfer Operations, Third
Edition. McGraw-Hill Book Company.
27
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Appendix A
Key Contacts for the SITE Demonstration
29
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Appendix A Contents
Page
AWD Technologies 31
EPA Regional Office 31
SITE Project Managers 31
The SITE Program 31
30
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Appendix A
Key Contacts for the SITE Demonstration
Additional information on the AWD technology, the
demonstration site, and the SITE Program can be
obtained from the following sources.
AWD Technologies
David Bluestein
Director of Industry Marketing
AWD Technologies, Inc.
49 Stevenson Street
San Francisco, CA 94105
415/227-0822
The SITE Program
Director, Superfund Technology
Demonstration Division
Robert Olexsey
U.S. Environmental Protection Agency
Office of Research and Development
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH 45268
513/569-7861
Chief, SITE Demonstration and
Evaluation Branch
Steve James
U.S. Environmental Protection Agency
Office of Research and Development
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH 45268
513/569-7696
Chief, SITE Demonstration Section
John Martin
U.S. Environmental Protection Agency
Office of Research and Development
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH 45268
513/569-7758
SITE Program, EPA Headquarters
Jim Cummings
U.S. Environmental Protection Agency
Technology Innovation Office (OS-110W)
401 M. Street, S.W.
Washington, DC 20460
703/308-8796
S/7E Project Managers
Norma M. Lewis and Gordon M. Evans
U.S. Environmental Protection Agency
Office of Research and Development
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH 45268
513/569-7665 and 513/569-7684
EPA Regional Office
Alisa Greene
U.S. Environmental Protection Agency
Superfund Remedial Branch (H-6-1)
Hazardous Waste Management Division
75 Hawthorne Street
San Francisco, CA 94105
415/744-2248
31
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Appendix B
Vendor's Claims for the Technology
33
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Appendix B Contents
Page
Introductioa 36
The Technologies 36
System Advantages 38
The Project 39
Operating Costs 40
References 41
34
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Tables
Number Page
B-l Strippable EPA-Designated Priority Pollutants 38
B-2 Integrated System at Lockheed-Burbank Design Criteria and
Performance Results 41
35
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Appendix B
Vendor's Claims for the Technology
Note: This appendix to EPA's Applications Analysis
Report was prepared by AWD Technologies. Claims
and interpretations of results in this appendix are those
made by the vendor and are not necessarily substantiated
by test or cost data. Many of AWD's claims regarding
performance can be compared to the available test data
in Appendix C.
Introduction
The Lockheed Aeronautical Systems Company (LASC)
has over 200 acres of aircraft manufacturing facilities
located in Burbank, California. Among the famous
aircraft that have been assembled at this facility are the
P-38 Lightning, the F-104 Starfighter, the U-2, and the
L-1011.
In late 1987, solvent-contaminated soil and groundwater
were identified near Building 175. As a result, the Los
Angeles Regional Water Quality Control Board
(RWQCB) issued a Cleanup and Abatement order
requiring soil and groundwater remediation to
commence by August 1, 1988, and October 15, 1988,
respectively.
LASC selected AWD Technologies, Inc. (AWD) to
design, install, and operate a treatment facility to meet
the requirements of the RWQCB. AWD is a wholly
owned subsidiary of The Dow Chemical Company.
AWD provides a comprehensive range of services for
remediation of contaminated soil and groundwater and
can draw upon the specialized resources and expertise
of its parent company.
The Technologies
Two existing technologies were integrated in an
innovative way: AquaDetox®, a low-pressure steam
stripping technology developed by Dow Chemical to
extract volatile organic compounds (VOC) from the
groundwater, and Soil Vapor Extraction (SVE) for the
treatment of the VOCs in the vadose zone. The
following paragraphs describe the unique features of
these technologies. Their integration will be described
in a subsequent section.
AquaDetox®
Over the past several years, an effort has been under way
to improve the efficiency of air stripping in removing
contaminants from groundwater. This work has led to
the development of the AquaDetox® technology, which
surpasses more conventional approaches to air stripping
in terms of removal efficiency. In most cases,
AquaDetox® can reduce contaminants in groundwater
to below maximum contaminant levels (MCL) without
liquid-phase carbon bed treatment. Moderate vacuum
and deep vacuum AquaDetox® steam stripping go even
further, allowing the near total recovery of contaminants
for possible recycling.
AquaDetox® technology can be used to remove a wide
variety of volatile compounds, and many compounds
that are normally considered "nonstrippable" (i.e., those
with boiling points in excess of 200°C). The application
of AquaDetox® for the removal of compounds with
boiling points greater than 200°C and the use of vacuum
are patented by the Dow Chemical Company.
Stripping is commonly defined as a process to remove
dissolved volatile compounds from water. A carrier gas,
such as air or steam, is purged through the contaminated
water, with the volatile components being transferred
from the water into the gas phase. While the physical
principles involved are straightforward, the practice of
stripping has undergone considerable development since
the early 70s.
36
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Dow's effort has focused on:
• Development of the proper theoretical relationships
that provided a clear understanding of the stripping
process.
• Application of these relationships, along with the
correct hardware, to attain higher levels of
contaminant removal than previously possible.
• Development of the proper scale-up parameters to
go from pilot units handling less than 1 gallon per
minute (gpm) to production units handling over 3000
gpm.
• Development of the conditions under which
compounds with very high boiling points (e.g.,
200°C) can be stripped from water.
• Compilation of a vapor-liquid equilibrium data base
with special emphasis on EPA priority pollutants.
The effort necessary to address these criteria has been
carried out by the Separations Section of the Applied
Science and Technology Department of Dow. The
research and development has been under the direction
of Dr. Lanny Robbins.
By the early 1980s, the result of this effort was the
AquaDetox® process, an innovative technology for the
high efficiency stripping of organic contaminants from
water.
AquaDetox® is capable of effectively stripping over 90
of the 110 volatile compounds listed in CFR 40, July 1,
1986, by the EPA (see Table B-l). The ability of
AquaDetox® to efficiently attain low levels of
contamination in the effluent represents a major
breakthrough. Conventional strippers will normally
achieve only 95 to 98 percent removal of the
contamination, whereas AquaDetox® can achieve up to
99.99 percent.
Another major concern raised regarding conventional
stripping systems is that they simply transfer
contaminants from the water to the air. The
contaminated air is usually treated over carbon beds, but
can still release significant amounts of contaminants to
the atmosphere. The AquaDetox® steam stripper
(moderate or deep vacuum) condenses the contaminated
steam to form a multi-phase liquid from which the liquid
phase contaminant can be decanted for possible
recycling. Only a small stream of noncondensable gases
is emitted following carbon treatment.
There are three versions of the basic AquaDetox®
technology:
• Air Stripping AquaDetox®.
• Moderate Vacuum AquaDetox® (requires source of
steam).
• Deep Vacuum AquaDetox® (does not require source
of steam).
Typical schematic flow diagrams for each of the types
of AquaDetox® technology are included in the paper by
Street, Robbins, and Clark.
Soil Vapor Extraction
Soil vapor extraction (SVE) is a technology commonly
applied for the in-situ removal of VOCs from soil. A
vacuum is applied to vadose zone extraction wells to
induce air flows within the soil toward the wells. The
air acts as a stripping medium which volatilizes the
VOCs in the soil. Soil-gas from the extraction wells is
typically treated in carbon beds before release to the
atmosphere. Alternatively, the treated soil-gas is
reinjected in the soil to control the direction of air flow
in the soil.
Integrated System
The integrated system consists of two basic processes:
an AquaDetox® vacuum stripping tower using low-
pressure steam and a soil-gas vapor
extraction/reinjection process. The system removes
VOCs from the groundwater and soil with no gaseous
emissions to the atmosphere.
Integrating the two technologies creates a unique system.
While the AquaDetox® system extracts and treats
contaminated groundwater, an array of SVE wells
removes contaminated soil-gas from the vadose zone.
The soil-gas is treated by the carbon beds and reinjected
into the ground to sweep through the soil and remove
additional contamination.
The AquaDetox® and SVE systems share a 3-bed
granulated activated carbon (GAC) unit. When one of
37
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Table B-1. Strippable EPA-Designated Priority Pollutants
Volatiles
acrolein
acrylonitrile
benzene
bromoform
carbon tetrachloride
chlorobenzene
chlorodibromomethane
chloroethane
2-chloroethylvinyl ether
chloroform
dichlorobromomethane
1,1-dichloroethane
1,2-dichloroethane
1,1 -dichloroethy lene
1,2-dichloropropane
1,3-dichloropropylene
methyl bromide
methyl chloride
methylene chloride
1,1,2,2-tetrachloroethane
tetrachloroethylene
toluene
1,2-trans-dichloroethylene
1,1,1-trichloroethane
1,1,2-trichloroethane
trichloroethylene
vinyl chloride
Acid Compounds
2-chlorophenol
2,4-dichlorophenol
2,4-dimethylphenol
p-chloro-m-cresol
pentachlorophenol
2,4,6-trichlorophenol
Base/Neutral
acenaphthene
acenaphthylene
anthracene
benzidine
benzo(a)anthracene
benzo(a)pyrene
3,4-benzofluoranthene
benzo(ghi)perylene
benzo(k)fluoranthene
bis(2-chloroethoxy)methane
bis(2-chloroethyl)ether
bis(2-chloroisopropyl)ether
bis(2-ethylhexyl)phthalate
4-bromophenyl phenyl ether
butylbenzyl phthalate
2-chloronaphthalene
4-chlorophenyl phenyl ether
chrysene
1,2-dichlorobenzene
1,3-dtehlorobenzene
1,4-dichlorobenzene
S.S'-dichlorobenzidine"
di-n-butyl phthalate
2,4-dinitrotoluene
2,6-dinitrotoluene
di-n-octyl phthalate
1,2-diphenylhydrazine"
(as azobenzene)
fluroanthene
fluorene
hexachlorobenzene
hexachlorobutadiene
hexachlorccyclopentadiene
hexachloroethane
indeno(1,2,3-cd)pyrene"
isophorone
naphthalene
nitrobenzene
N-nitrosodimethylamine*
N-nitrosodi-n-propylamine1
N-nitrosodiphenylamine*
phenanthrene
pyrene
1,2,4-trichlorobenzene
Pesticides
aldrin
alpha-BHO
beta-BHC-
delta-BHC-
chlordane
4,4'-DDT
4.4'-DDE
4,4'-DDD
dieldrin
alpha-endosulfarr
beta-endosulfan*
endosulfan sulfate*
endrin aldehyde*
heptachlor
heptachlor epoxide
PCB-1242-
PCB-1254-
PCB-122V
PCB-1232-
PCB-1248-
PCB-12601
PCB-1016'
toxaphene
• Needs further pilot study to determine treatability.
the GAC beds is regenerated, the steam and organic
vapors are condensed in the secondary condenser of the
Aquadetox® System. Condensed organics are pumped
to a storage tank for recycle, water condensate is pumped
to the recycle tank for further treatment by the
AquaDetox® process, and noncondensables are
transferred to the active GAC bed.
The integrated system was given a patent on July 11,
1989.
System Advantages
The advantages of the AquaDetox®/SVE system are:
The AquaDetox®/SVE integrated system when
utilized as described in this appendix results in zero
air emissions.
Can be utilized with very high concentrations of
VOCs in both the groundwater and soil vapor.
Concentrations of VOCs in the groundwater in
excess of 200,000 |ig/L and 12,000 parts per million
(ppm) in the soil vapor can be handled by the
AquaDetox®/SVE integrated system.
The sizing of an AquaDetox® steam stripping
system, for a particular groundwater flow rate, is not
significantly impacted by VOC concentration up to
approximately 200,000
38
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• Greatly reduced usage of GAC. At the Lockheed
site the GAC beds have not been replaced since the
start of operation in September 1988.
• Recovery of the organic solvent as a liquid phase.
This recovered solvent can be disposed of through
a solvent recycler.
The Project
On February 1, 1988, LASC awarded AWD a contract
for pilot-testing, design, and installation of an integrated
1200-gpm groundwater treatment plant and a 300-
standard cubic feet per minute (scfm) S VE system. Fast-
track project techniques were used, and 7-1/2 months
later all systems of the $4 million project were
operational.
Groundwater Treatment Facility
The groundwater treatment technology at the Lockheed
site is the moderate vacuum steam stripper AquaDetox®
system.
Contaminated groundwater is fed from extraction wells
to a cross exchanger, where it is heated by the treated
water. The heated water then enters the top of the
stripping column (9-feet diameter by 60 feet tall) and
flows down the column, contacting the rising vapor flow
generated by the introduction of steam to the bottom of
the column. Under a pressure of 100 mm Hg (absolute),
the contaminants are stripped from the liquid into the
vapor stream, which exits from the top of the column.
The treated water leaves the bottom of the column. The
treated water passes through a heat exchanger, where it
is cooled and the contaminated feedwater is heated. The
water exiting the treatment facility is thereby 9 to 10°F
higher than the incoming groundwater.
The overhead vapors flow to a water-cooled condenser,
where the water vapor is condensed and recycled back to
the contaminated feedwater. The water for cooling the
condenser is provided by diverting a portion of the cool
feed stream through the condenser and back to the main
feed stream. Total condensation of the overhead vapors
is not possible due to noncondensable gases from
"vacuum leaks" and dissolved gas contained in the
contaminated groundwater. These noncondensable
vapors, carrying some water, inert gases, and VOCs,
enter a vacuum pump where they are compressed to
atmospheric pressure. Cooling of this compressed vapor
stream results in condensation of water and VOCs.
The water phase is recycled to the contaminated
feedwater and the organic solvent phase is withdrawn
for reclamation by a contract recycler. The coolant for
this secondary condenser is supplied from the feedwater
as is done for the first condensing unit.
The vent stream from the secondary condenser contains
the noncondensables and an equilibrium quantity of
VOCs. This stream is passed through vapor-phase GAC
prior to discharge into the re-injection wells of the SVE
system.
Soil Vapor Extraction System
Soil vapor extraction (SVE) is being used at the
Lockheed site for remediation of contaminated soil
because of the relatively volatile character of the
reported contaminants, depth to groundwater in the
range of approximately 150 to 170 feet, and the
predominantly coarse-grained nature of subsurface soils.
The design of the SVE system focused on the
distribution of the wells to produce an effective and
nondisruptive pneumatic flow regime. "Effectiveness"
of SVE was judged to depend on establishing radially
inward flow (toward an extraction well) throughout the
areas of probable soil contamination; "nondisruptive
pneumatic flow regime" refers to injection well
placement such that (1) fugitive atmospheric emissions
are not created, and (2) soil-gas within the areas of
probable soil contamination is not displaced from the
zone of extraction well influence.
Extraction wells connected to a common header feed up
to 300 scfm of contaminated soil-gas to the system for
processing and decontamination via carbon adsorption.
Liquids collected in the SVE scrubber sump are pumped
to the water recycle tank for processing through the
AquaDetox® tower. Vapors are exhausted to the GAC
beds for hydrocarbon removal prior to reinjection.
Three GAC beds remove chlorinated hydrocarbons from
SVE system extraction well soil-gas, along with vent
gases from the AquaDetox® system. The GAC beds are
operated alternately, with two beds on-line in series
while the remaining unit is being regenerated. Once
each 8 hours, the regenerated off-line bed is placed in
39
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service and the spent carbon bed is removed from service
and regenerated. Steam is used to strip chlorinated
hydrocarbons from the GAC units. The vapors from this
regeneration process are condensed and processed in the
AquaDetox® separator.
Treated soil-gas is reinjected into the ground at depths
ranging from 50 to 150 feet through the vadose zone.
The soil-gas then sweeps horizontally through the
contaminated soil, picking up additional hydrocarbons,
and is once again collected in the soil-gas extraction well
system, where hydrocarbons are again removed.
System Operation
The groundwater treatment plant operates at an average
flow rate of 1,000 gpm and the SVE at 170 scfm. The
contaminants treated are listed in Table B-2. Initially,
total VOC concentrations were 12,000 jig/L in the
groundwater and 6,000 ppm in the soil-gas. After the
integrated system had been operating several months,
these concentrations had dropped to 5,000 [igfL and 450
ppm, respectively. At these lower levels, the
AquaDetox®/SVE facility removes 60 pounds per day
of PCE/TCE from the groundwater and 45 pounds per
day from the soil-gas.
Table B-2 lists the major contaminants in the
groundwater feed to the treatment plant. Effluent
analyses show that all contaminants have been reduced
to below the analytical detection level. This equates to
a removal efficiency in excess of 99.99 percent. The
soil-gas treatment by two of three 3,500-pound carbon
beds removes VOCs to below 2 ppm before the air is
reinjected in the ground. This equates to a removal
efficiency of better than 99 percent.
While the treatment plant has operated consistently at
average design flow rates (95 percent availability factor)
and has produced water effluents at nondetectable VOC
concentrations, it has not been devoid of typical start-
up problems and one operational problem. The start-
up problems were typically failures of instrumentation
and control software bugs, which have since been
resolved. A more persistent problem, however, has been
caused by the high alkalinity of the groundwater and
resulting calcium carbonate scaling in parts of the
treatment plant.
Solubility of the calcium carbonate in the groundwater
is reduced in two ways as the water is processed through
the AquaDetox® system. First, the water is heated and,
second, carbon dioxide is removed during the stripping
process in the column, thereby increasing the pH. The
principal disadvantage of scaling is the reduction in heat
transfer efficiency of the cross exchanger, resulting in
greater steam consumption. Initially, an antiscalant was
injected into the feed water but could not totally halt the
scaling due to the subsequent removal of carbon dioxide
and concomitant pH increase. Periodically, the heat
exchanger was acidified to maintain its heat transfer
properties.
To resolve the scaling problem a sulfuric acid injection
system was installed to control pH and eliminate scaling.
The costs associated with the addition of sulfuric acid
will be offset by: (1) the savings resulting from
eliminating antiscalant injection; (2) the savings
associated with the elimination of phosphoric acid used
to periodically clean the heat exchanger; and (3) lower
average steam consumption due to improved heat
exchanger efficiency. Less than 20 percent of the steam
consumption in the AquaDetox® facility is needed to
strip contaminants, the other 80 percent is needed to
raise the incoming water to its boiling point of 120°F at
100 mm Hg. The cross exchanger helps reduce this
steam requirement by using heat from the effluent water.
This is a highly energy-efficient and cost-effective
approach, and future systems will have even larger heat
exchangers.
Operating Costs
Annual operating costs for the AquaDetox®/SVE plant
at LASC are:
Labor: One individual was initially assigned full-
time for the maintenance and operation of the
facility, but after the first 6 months of operation, his
time was reduced to 3 days per week. At the start of
the third year of operation, 16 hours per week have
been scheduled. Current labor costs are about
$5,900 per month.
Steam: Steam, which is presently provided by an
existing Lockheed boiler, is costed at $5.70 per
1,000 pounds. At a flow rate of 1,000 gpm, the
steam consumption is 3,500 Ib/hr before calcium
carbonate scaling shows its effect on the cross
exchanger efficiency. An additional 340 Ib/hr of
steam (equivalent continuous average) is used to
regenerate the carbon beds. This results in a total
40
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Table B-2. Integrated System at Lockheed-Burbank Design Criteria and Performance Results
AquaDetox®
Design Contaminants
Trichloroethylene
Toluene
Tetrachloroethylene
Trans-1 ,2-dichloroethylene
Chloroform
1,1-dtehloroethane
1 ,2-dtehloroethane
Carbon tetrachloride
Benzene
1 , 1 ,2-trichloroethane
Ethylbenzene
Soil Vapor Extraction
Design Feed
Water Concentration
(W/L)
3300.0
180.0
7650.0
19.5
30.0
18.0
4.5
7.5
30.0
34.5
255.0
Actual (11/88)
Influent Concentration
(M9/L)
2200
<100
1 1 ,000
<100
<100
<100
<100
<100
<100
<100
<100
Design Effluent
Concentration
(ng/L)
4.5
9.5
3.5
15.0
N/A
5.5
0.8
N/A
0.65
N/A
N/A
Actual Effluent
Concentration
(Mg/L)
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Appendix C
SITE Demonstration Results
43
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Appendix C Contents
Page
Introductioa 46
Site Characteristics 46
Treatment System Performance 47
Review of Treatment Results 50
References 54
44
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Figures
Number Page
C-l North Hollywood Well Field Map 47
C-2 Lockheed Site Location 48
C-3 Percent Removal of VOCs from Groundwater for all Test Runs 51
C-4 Percent Removal of VOCs from Soil-Gas for all Test Runs 52
C-5 95-Percent Upper Confidence Limits of TCE and PCE
Concentrations in Effluent Groundwater Samples for all
Test runs 54
Tables
C-l AWD SITE Demonstration Schedule and Test Run Conditions 49
C-2 Summary of Total Groundwater TCE and PCE Concentrations
and Percent Removal Data 52
C-3 Summary of Total Soil-Gas TCE and PCE Concentrations and
Percent Removal Data 53
45
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Appendix C
SITE Demonstration Results
Introduction
Appendix C presents a brief history of the Lockheed site
and summaries of the AWD SITE demonstration results.
In January 1989, EPA solicited proposals from
technology developers to demonstrate innovative
technologies at Superfund sites under the SITE program.
In response, AWD Technologies submitted a proposal
for its integrated AquaDetox®/SVE technology. This
technology is currently being used for remediating
contamination at the Lockheed Aeronautical Systems
Company (LASC) at the San Fernando Superfund Site,
Area I (Burbank/North Hollywood Well Field) in
Burbank, California. Figure C-l includes a map of the
North Hollywood Well Field and shows the location of
the Lockheed site. The Lockheed site and the AWD
treatment facility are shown on Figure C-2. Through a
cooperative effort between EPA's Office of Research
and Development (ORD), EPA's Office of Solid Waste
and Emergency Response (OSWER), EPA Region IX,
AWD Technologies, and LASC, the technology was
demonstrated under the SITE program at the Lockheed
site in September 1990.
Site Characteristics
Groundwater contamination in the San Fernando Valley
Groundwater Basin (SFVGB) wells was first discovered
in 1980. Los Angeles Department of Water and Power's
(LADWP) groundwater monitoring program (conducted
from 1981 through 1987) revealed that TCE and PCE
had contaminated approximately 50 percent of the water
supply wells in the eastern SFVGB at concentrations
exceeding Federal and state drinking water standards.
LASC has over 200 acres of aircraft manufacturing
facilities located in Burbank, California. In addition,
EPA has identified approximately 30 other potentially
responsible parties associated with the Burbank/North
Hollywood Well Field. Late 1987, solvent-
contaminated soil and groundwater were identified near
the Lockheed site. As a result, the California Regional
Water Quality Control Board, Los Angeles Region,
issued a Cleanup and Abatement order requiring soil and
groundwater remediation to commence by August 1,
1988, and October 15,1988, respectively.
The results of a monitoring program by the City of
Burbank, which routinely samples several Public Service
Department (PSD) wells in its vicinity indicated that
TCE and PCE concentration levels in the groundwater
exceeded the maximum contaminant levels (MCL),
which are 5.0 |ig/L for both TCE and PCE. Most of the
PSD wells are within a 2-mile radius of the Lockheed
site, with the wells closest to the site showing the
greatest contamination. The groundwater treated during
the AWD SITE demonstration was extracted from an on-
site extraction well at the Lockheed site.
An operable unit feasibility study, performed by James
M. Montgomery Consulting Engineers, Inc. (JMM) for
LADWP in 1988, confirmed the presence of VOCs in a
number of wells in the SFVGB. In addition to TCE and
PCE, trace quantities of other VOCs, including
methylene chloride, toluene, acetone, carbon
tetrachloride, methyl ethyl ketone, and the
trihalomethanes, chloroform, bromodichloromethane,
and dibromochloromethane, were detected (JMM, 1988).
Lockheed has routinely monitored the performance of
the AWD treatment system in its Burbank site since the
system became operational in September 1988. Influent
and effluent groundwater and soil-gas samples are
routinely collected and analyzed to ensure proper
operation of the system. Samples from the first 10
months of operation showed groundwater TCE
contamination in the 1,100 to 2,300 |ig/L range and PCE
contamination ranging from approximately 9,000 to as
46
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Figure C-1. North Hollywood Well Field Map.
high as 22,000 |ig/L. During this period, soil-gas
contamination was approximately 100 ppm for TCE and
6,000 ppm for PCE.
Concentrations of contaminants in the groundwater and
soil-gas have dropped with continued operation of the
system. Influent TCE and PCE concentrations observed
during the demonstration were considerably less than
those previously mentioned. Concentrations in the
influent groundwater samples collected during the SITE
demonstration were typically in the 400 to 600 ug/L
range for TCE and 2,000 to 2,500 ng/L range for PCE.
Soil-gas samples from the demonstration had
concentrations of approximately 10 ppm for TCE and
400 ppm for PCE. No other VOCs were detected in the
groundwater or soil-gas at the site.
Treatment System Performance
A review of the system's performance and any
operational problems during the technology
demonstration and a description of site preparation and
demobilization efforts are presented in this section.
Site Preparation
Site preparation included minor modifications to the
treatment system already on-site, and setup of on-
support services and utilities. Unlike most other SITE
projects, the AWD technology was demonstrated by
using an already-installed, operational system at the
Lockheed site. As such, set up of the treatment system,
system start up procedures and teardown of the system
after completion of the demonstration were not required.
However, the existing system was slightly modified for
the demonstration.
The modifications included the addition of stainless steel
sampling ports to the GAC beds to facilitate soil-gas
sample collection and suspension of two normal
operational practices for the duration of the 2-week
demonstration. Sulfuric acid is normally added to the
influent groundwater to prevent scaling problems in the
47
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i
EMPIRE AVENUE
LEGEND:
A INDICATES APPROXIMATE LOCATION OF VAPOR
• INDICATES APPROXIMATE LOCATION OF VAPOR
9 INDICATES APPROXIMATE LOCATION OF
QROUNDWATER EXTRACTION WELL
Figure C-2. Lockheed Site Location.
AquaDetox® stripping tower. Sulfuric acid addition was
suspended during the demonstration to allow better
control of the stripping tower pressure. The second
suspended practice was the addition of the vacuum
pump's lubricant to the recovered solvents. Typically a
heavy lubricant is circulated through the vacuum pump
and discharged to the recovered solvent at a very low
flow rate. The lubricant was collected in a 55-gallon
drum during the demonstration to minimize its effect on
the quality of the recovered solvents.
On-Site Support Services
On-site laboratory analyses were conducted in a field
trailer. The field trailer also served as an office for field
personnel, provided shelter and storage for equipment
and supplies, and acted as a base for site security
personnel. Two portable toilets were located near the
trailer. The trailer was equipped with a fax machine and
a copy machine. Although the treatment system at the
Lockheed site is enclosed by a fence and Lockheed
security patrols the area periodically, a commercial
security service was hired to provide additional
protection from equipment theft or vandalism during the
evening hours and weekends.
Utilities
All utilities required for the operation of the AWD
system were obtained from sources at or near Lockheed
facilities. Utilities required for the on-site office trailer
included electrical and telephone services and water.
Water was required for drinking and personnel
decontamination. Bottled water was used for both
purposes.
Telephone service was required to order supplies,
coordinate site activities, and provide communication.
Two telephone lines were installed in the trailer. An on-
site diesel generator provided electricity to the office
48
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trailer. Canopies provided shelter from direct sunlight to
the personnel, as well as the sampling equipment.
Technology Demonstration
The AWD Technology was demonstrated over a 2-
week period in September 1990. The SITE
demonstration consisted of 21 test runs performed under
varying operating conditions. The test runs were
grouped into six phases. Phase 1 test runs were
performed at AWD-specified operating conditions
(tower pressure at 105 mm Hg, steam flow rate at 3,800
Ibs/hr, and groundwater flow rate at 900 gpm). The
steam flow rate was varied in Phase 2 test runs. Steam
flow rates and tower pressures were varied
simultaneously in Phases 3 and 4. The groundwater flow
rate was varied in Phase 5 test runs. Phase 6 involved
the SVE system, in which the GAC bed regeneration
frequency was varied. During the 2-week period, the
demonstration schedule was significantly modified to
accommodate several operational problems or
limitations. Table C-l lists the operating conditions for
each test run.
Operational Problems
Operational problems are grouped into two categories:
(1) equipment related problems, and (2) nonequipment
related problems. A description of each follows.
Equipment Related Problems
A dry run (a practice run where collected samples are
not analyzed) was attempted on Friday, September 7.
During the dry run it was determined that additional
sampling ports were required to collect all the soil-
gas samples that were outlined in the demonstration
plan. Stainless steel sampling ports were installed by
contracted welders on the morning of September 10.
The demonstration was started in the afternoon of
September 10, 1990. The system performed with no
equipment related problems during the first 4 days of
testing. However, a broken SVE blower prevented
operation of the system on September 14. The
replacement parts required to repair the broken blower
were shipped by a supplier and were not available until
Table C-1. AWD SITE Demonstration Schedule and Test Run Conditions
Run Number
1
2
3
4
5
6
7
8
9-
10-
11
12
13
14
15
16
17
18
19
20
21
GAC-A
GAC-B
Phase Number
1
2
2
2
1
3
3
3
3
3
1
4
4
4
4
1
5
5
5
5
1
6
6
Groundwater
Flow Rate (gpm)
900
900
900
900
900
900
900
900
~
—
900
600
600
600
600
900
600
700
800
970
900
900
900
Tower
Pressure (mm Hg)
105
105
105
105
105
150
125
160
—
—
105
105
95
85
75
105
105
105
105
105
105
105
105
Steam
Flow Rate (Ib/hr)
3,800
3,750
3,700
3,850
3,800
4,800
4,350
5,100
—
—
3,800
2,600
2,400
2,200
2,000
3,800
2,600
2,700
3,300
4,100
3,800
3,800
3,800
GAC Bed
Regeneration Period (hr)
8
8
8
8
8
8
8
8
-
—
8
8
8
8
8
8
8
8
8
8
8
16
24
• These runs were not performed because the desired conditions could not be attained.
49
-------
the morning of September 18. The blower was fixed in
the afternoon and demonstration activities resumed.
Even though Lockheed stocks many spare parts on-
site, it is not practical for Lockheed to store every spare
part to avoid an extended down time as occurred during
the SITE demonstration.
Another equipment related problem was the performance
of the system at higher tower pressures. High stripping
tower pressure runs in Phase 3 (Runs 9 and 10) had to be
modified or cancelled altogether because the system
could not reach steady state conditions or it would shut
down completely.
Runs 9 and 10 were originally planned to operate at
pressures of 300 and 350 mm Hg, respectively.
However, these tower pressures were unattainable and
the test runs were canceled. At 300 mm Hg, the
operating temperature of the stripping tower was
increased by 24° C due to the higher boiling point of
water at this pressure. The effluent groundwater exiting
the stripping tower at this higher temperature was
causing cavitation problems in the groundwater pump.
Pump cavitation occurs as liquid enters the pump
chamber and literally boils or vaporizes due to the low
pressure conditions within the chamber.
To avoid the pump cavitation problem the conditions for
Runs 7 and 8 were modified. However, it was difficult
to maintain the stability of the system even at a relatively
low pressure range of 150 to 160 mm Hg. The vacuum
pump at the Lockheed site operates at full capacity at all
times. To achieve pressures in the 150 to 160 mm Hg
range, a control valve used to adjust the intensity of the
vacuum was nearly shut. Therefore, even small
adjustments to the control valve impacted the tower
pressure significantly. Consequently, steady state
conditions took considerably longer to achieve and were
difficult to maintain in these runs.
Nonequipment Related Problems
The demonstration schedule was modified several times
due to the unusually hot weather during the first week of
testing. Mid-day temperatures in excess of 100°F during
the first week of the demonstration greatly reduced the
effectiveness of the vacuum pump. Many of the runs
requiring a pressure of 105 mm Hg or lower were
postponed or were performed early in the morning to
avoid problems related to the high ambient temperatures.
Another nonequipment related problem was the
interruption of Run 2 when it was discovered that the
incorrect operating parameters were set. The correct
operating parameters were then established and Run 2
was restarted.
Demobilization
As previously mentioned, tear down and demobilization
of the treatment system equipment was not required for
this project. Removal of the on-site office trailer,
utilities, and related equipment w as accomplished within
the first week after completion of the demonstration.
Contaminated materials, such as empty sample
containers, laboratory wastes, and disposable protective
equipment generated during the demonstration, were
placed in a 55-gallon, open-top drum. These materials
contained only residual contamination.
Review of Treatment Results
The AWD technology demonstration involved: (1)
performing tests on appropriate process streams with
operating parameters set at AWD-specified values to
confirm that the system is viable for use at Superfund
sites and (2) evaluating the ability of the system to
remove VOCs from groundwater and soil-gas under
varying operating conditions. The operating parameters,
including the steam flow rate, stripping tower pressure,
groundwater flow rate, and GAC bed regeneration
frequency, were varied throughout the demonstration,
and the system's performance was evaluated under each
set of operating conditions.
The AWD system is designed to treat VOC-
contaminated groundwater and soil. In addition, the
only organics detected at the site were TCE and PCE.
Therefore, the major performance criterion for this
demonstration was percent removal of TCE and PCE
from contaminated groundwater and soil-gas. The
system's compliance with groundwater regulatory
discharge requirements for TCE and PCE (5 [ig/L each)
was also monitored.
Quantifiable Results
The AWD technology achieved removal efficiencies as
high as 99.99 percent for both TCE and PCE from the
groundwater. On the average, the removal efficiencies
50
-------
were slightly higher for PCE than TCE (Figure C-
3). Removal efficiencies for total VOCs (TCE and PCE)
ranged from 99.92 to 99.99 percent (Table C-2).
The three runs with the lowest removal efficiencies,
Runs 11, 18, and 19, were all performed on September
18 after the system was inoperable for 4 days. The
system may not have been operating efficiently after
being shut down for several days.
removes the majority of the VOC contamination from
the soil-gas. The secondary GAC bed, functioning as a
fail-safe device removes any remaining contamination.
It is therefore, expected that the VOC concentrations be
higher in the effluent of the primary GAC bed.
Based on sample collection information, it was
determined that VOC concentrations were higher in the
secondary GAC bed effluent only when GAC bed No. 3
was being used as the secondary bed. Two possible
!
99.98 - gr-j ^
99.97 - a \ ^
r ^ i
99.95 - ^ ^ ^
99.94- | | ^
99.93 - ^ ^ ^
99.92 - ^ jl ^
1 1 I
99.91 - ^ S ' S
9990- L. L L
II.
I
I
'. ^B TCE Removal
111
I
I
'
I
I
I
i
SS PCE Removal l~~l Total VOC Removal I
i
1
1
1
1
1
1
I
I
I
8 11 12 13 14
Test Run Number
15
16 17
18 19
20 21
Figure C-3. Percent Removal of VOCs from Groundwater for all Test Runs.
Removal efficiencies for total VOCs from soil-gas
ranged from a low of 93.4 percent to as high as 99.9
percent (Figure C-4). As expected, lower removal
efficiencies were observed when the GAC beds were
regenerated less frequently (Phase 6 Runs GAC-A and
GAC-B). However, even after 24 hours of operation
without steam regeneration, the primary GAC bed
removed more than 99 percent of VOCs from the soil-
gas.
As shown in Table C-3, for several runs (those with a
negative percent removal in the secondary GAC bed)
the effluent from the first on-line GAC bed was actually
cleaner than the effluent from the second on-line bed.
As the primary GAC bed, the first on-line GAC bed
explanations exist: (1) GAC bed No. 3 was not
performing as designed or (2) the samples were collected
in the incorrect order. That is, the primary GAC bed
effluent samples were labeled as the secondary bed
effluent and vice versa. The removal efficiencies listed
in Table C-3 were calculated based on the first
explanation. However, if the samples were collected in
the wrong order, the removal efficiencies would be even
higher.
SVOCs, PCBs, and other VOCs were not detected in
groundwater samples. Total organic carbon (TOC) and
total dissolved solids (TDS) analyses were also
performed. SVOC, PCB, TOC, and TDS analyses were
only performed for the first test run. Alkalinity,
51
-------
Table C-2. Summary of Total Groundwater TCE and PCE Concentrations and Percent Removal Data
Run
No.
1
2
3
4
5
6
7
8
9-
10-
11
12
13
14
15
16
17
18
19
20
21
Influent Concentrations (uo/U
TCE
488
489
498
562
522
495
542
548
-
—
530
620
554
544
544
491
620
615
814
515
475
PCE
2010
1930
2080
1920
2080
2170
2100
2390
-
-
2770
2520
2320
2550
2620
2420
2520
2800
4080
2130
2080
Total
2500
2420
2580
2470
2610
2670
2640
2940
-
-
3300
3140
2870
3090
3160
2910
3140
3420
4900
2650
2550
Effluent Concentrations
TCE
0.15
0.15
0.15
0.15
0.15
0.15
0.15
0.15
-
-
0.20
0.15
0.15
0.15
0.15
0.15
0.15
0.43
0.53
0.15
0.15
PCE
0.80
0.43
0.20
0.20
0.20
0.93
0.53
0.33
--
--
1.67
0.70
0.43
0.43
1.13
0.33
0.70
2.37
2.70
0.20
0.67
(uo/U
Total
0.95
0.58
0.35
0.35
0.35
1.08
0.68
0.48
-
-
1.87
0.85
0.58
0.58
1.28
0.48
0.85
2.80
3.23
0.35
0.82
Total
%Removed
99.96
99.98
99.99
99.99
99.99
99.96
99.97
99.98
—
—
99.94
99.97
99.98
99.98
99.96
99.98
99.97
99.92
99.93
99.99
99.97
These runs were not performed because the desired conditions could not be attained.
98-5 !
96-5 5
94-5 ;
92-5 5
90 - i :
88 - 55
86-5 5
84-5 !
82-5 5
80-5 !
78 - ; ;
76 - i 5
74-5 ;
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s s s
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s S S
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^ s s
s ^ S
> S S
s N
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s N S
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s s s
> s s
S S S
^~t
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s
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s
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s
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s
s
s
1
Nn
s
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s
s
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s
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s
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c
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s
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>
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s
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SSSSSSSSSSSSSSSSfSSSSSSSfSSSSSSSSffSSSSSfSfSSSSSSSSs
1
I
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; s • TCE Removal SS3 PCE Removal ED Total VOC Removal
; Rs
^ pjK
Rs
JB^
Bs
fis
fis
Rv
K »$ K
Ws. B^ ^^
B?
_Bv
B
H>
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-1
-,
^
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s
s
s
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s
s
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^
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s
s
s
J
^
0
c
c
R^l
Rs
K<
11 12 13 14 15
Test Run Number
16 17 18 19 20 21
GAC GAC
-A -B
Figure C-4. Percent Removal of VOCs from Soil-Gas for all Test Runs.
52
-------
Table C-3. Summary of Total Soil-Gas TCE and PCE Concentrations and Percent Removal Data
Run
No.
1
2
3
4
5
6
7
8
9"
10"
11
12
13
14
15
16
17
18
19
20
21
GAC-A
GAC-B
Primarv GAC Bed Conditions
Influent (ppmv)
643
968
566
922
1270
864
1080
1210
-
-
675
586
1190
606
730
726
586
993
1030
1350
846
863
389
Effluent (ppmv)
0.00
5.53
3.04
0.938
5.77
1.79
1.35
1.24
--
--
15.6
6.80
3.80
17.4
15.6
0.930
6.80
1.33
0.800
1.04
1.41
4.11
3.37
%Removed
100.
99.4
99.5
99.9
99.5
99.8
99.9
99.9
--
--
97.7
98.8
99.7
97.1
97.9
99.9
98.8
99.9
99.9
99.9
99.8
99.5
99.1
Secondary GAC Bed Conditions
Influent (ppmv)
0.00
5.53
3.04
0.938
5.77
1.79
1.35
1.24
-
-
15.6
6.80
3.80
17.4
15.6
0.930
6.80
1.33
0.800
1.04
1.41
4.11
3.37
Effluent (ppmv)
1.74
1.23
1.32
13.0
0.706
6.37
7.95
6.13
--
--
8.25
5.94
6.24
0.884
1.69
14.4
5.94
12.6
12.3
11.7
8.16
57.1
13.0
%Removed
NEC-
77.8
56.6
NEG
87.8
NEG
NEG
NEG
-
-
47.1
12.6
NEG
94.9
89.2
NEG
12.6
NEG
NEG
NEG
NEG
NEG
NEG
Total
%Removed
9a7
gag
gas
gae
99.9
gas
gas
gas
-
-
gas
gao
gas
99.9
gas
gao
gao
9a7
gas
gai
99.0
934
96.7
* Concentrations were higher in the secondary GAC bed effluent, resulting in negative removal efficiencies.
b These runs were not performed because the desired conditions could not be attained.
hardness, and pH measurements were performed for all
test runs. Hardness and pH values did not change
significantly after treatment. Alkalinity values were
lower in the effluent groundwater samples.
To eliminate the steam supply as a possible source of
contamination, condensed steam samples were collected
on the first and last day of the demonstration. TCE and
PCE concentrations for both steam samples were below
the detection limit.
Ninety-five percent upper confidence limit (UCL) values
for effluent groundwater TCE and PCE concentrations
were compared with the regulatory discharge
requirement for each compound for all test runs.
Although the operating conditions in some test runs were
less than optimum, the effluent from all test runs met the
regulatory discharge requirement. Figure C-5 shows the
UCL for each VOC and how it compares with the
regulatory discharge requirement in each test run.
Final Products of the Treatment Process
The final products of the AWD technology include the
treated groundwater and soil-gas, recovered VOCs, and
spent carbon from the GAC beds. Although the carbon
in the GAC beds at the Lockheed site has not required
replacement in over 2 years of operation, it is estimated
that GAC replacement may become necessary after
approximately 3 years of operation. The recovered
VOCs are collected in an on-site storage tank and
periodically trucked to an off-site recycler. During the
SITE demonstration approximately 17 pounds of VOCs
were recovered from the groundwater, as well as the
soil-gas (34 pounds total).
Accomplishing the Goals of the Technology
Demonstration
Specific goals for the AWD technology demonstration,
and an evaluation of how those goals were met, are
discussed below.
53
-------
6 -
:4 -
3 -
.2 -I
1 H
TCE CH PCE
Regulatory Discharge Limit
I
1 2 3 4 S 6 7
11 12 13 14 15 16 17 18
Test Run Number
19 20
21
Figure C-5. 95-Percent Upper Confidence Limits of TCE and PCE Concentrations in Effluent Groundwater Samples
for all Test Runs.
1. Goal: Evaluate the performance of the AWD
system and its removal efficiencies for VOCs from
groundwater and soil-gas at AWD-specified
operating conditions and under varying operating
conditions.
Result: The AWD system successfully treated
VOCs present in the groundwater and soil-gas at the
Lockheed site. Removal efficiencies as high as
99.99 percent were achieved for total VOCs present
in the groundwater. Removal efficiencies were as
high as 99.9 percent for total soil-gas VOCs.
2. Goal: Monitor the compliance of the AWD system
with regulatory discharge requirements.
Result: The effluent groundwater from all test runs
met the regulatory discharge requirements for both
TCE and PCE. Other organics were not detected.
3. Goal: Develop capital and operating costs for the
system.
Result: The AWD system costs approximately $3.2,
$4.3, and $6.0 million (1991$), for the 500-, 1,000-
, and 3,000-gpm systems, respectively. The total
annual operation and maintenance (O&M) costs are
approximately $510,000, $820,000, and $2,000,000
(1991$) for the 500-, 1,000-, and 3,000-gpm
systems, respectively.
4. Goal: Identify specific operating and maintenance
concerns.
Result: Problems with the SVE blower shut down
the system for 4 days. This and other operational
problems were noted.
References
James M. Montgomery Consulting Engineers, Inc.,
1988. Remedial Investigation of the San Fernando
Valley Groundwater Basin, Operable Unit
Feasibility Study, Burbank Well Field. JMM,
October 1988.
PRC Environmental Management, Inc., 1990.
Demonstration Plan for the AWD Technologies
Integrated AquaDetox®/SVE Technology. Prepared
for U.S. EPA, RREL, Cincinnati, Ohio, by PRC
SITE Team, September 1990.
54
-------
Appendix D
Case Studies
55
-------
Appendix D Contents
Page
Introduction 57
Case Study D-l, In-Situ Soil Vapor Extraction System, Northern California 57
Case Study D-2, AquaDetox® Groundwater Treatment, Southern California 58
Case Study D-3, AquaDetox® Vacuum Steam Stripping System,
King of Prussia, Pennsylvania 58
Case Study D-4, AquaDetox® Technology, Kalkaska, Michigan 59
Case Study D-5, Integrated AquaDetox®/SVE Treatment System,
Burbank.California 59
56
-------
Appendix D
Case Studies
Introduction
This appendix summarizes several case studies on the
use of AWD Technologies' treatment systems that have
been tested at five sites. Unlike the integration of the
AquaDetox®/SVE treatment systems at the Lockheed
facility in Burbank, four of these case studies involve the
separate applications of these treatment components.
The fifth case study presents the results of a test run
conducted by the California Department of Health
Services on the integrated system at the Burbank facility.
This appendix summarizes the following case studies:
Study System and Location
D-1 In-Situ Soil Vapor Extraction System,
Northern California
D-2 AquaDetox® Groundwater Treatment,
Southern California
D-3 AquaDetox® Vacuum Steam Stripping
System, King of Prussia, Pennsylvania
D-4 AquaDetox® Technology, Kalkaska,
Michigan
D-5 Integrated AquaDetox ®/SVE Treatment
System, Burbank, California
Case Study D-1
In-Situ Soil Vapor Extraction System,
Northern California
LOCATION:
PERFORMANCE
PERIOD:
ASSIGNMENT:
Northern California
1989 - Present
Design/Construct/Operate Soil
Vapor Extraction System
PROJECT:
CLIENT:
In-Situ Soil Vapor Extraction
System
Confidential
This site was previously an industrial warehouse.
Significant soil contamination identified at various soil
boring locations was confined to a small area at the site.
Soil is mainly comprised of silty sand to a depth of 5
feet. The major volatile organic compounds involved
are toluene, TCE, and 1,1,1-trichloroethane. A vapor
extraction system furnished with four in-line extraction
wells, vacuum blower, moisture trap, and emission
control unit was constructed to remove soil vapor in the
vadose zone. An in-situ vapor extraction test was
performed using the four in-line wells to evaluate the
feasibility of the soil treatment via vapor removal. One
well was used as the extraction well and the remaining
three wells served as monitoring wells. An explosion
proof vacuum blower removed soil-gas at a rate of
approximately 100 scfm during the test. The vacuum
head applied to the extraction well measured 40 inches
of water and the most distant monitoring well, 30 feet
away from the vacuum well, measured 5 inches of water.
Three monitoring wells had almost instant response to
the applied vacuum.
The vacuum measured in these wells was within a range
of 5 to 6 inches of water. Therefore, the radius of
influence caused by the applied vacuum was estimated
beyond 30 feet from the vacuum source. From this
result, the in-situ vapor extraction method was shown to
be an effective remedial technique for soil contamination
at the site.
57
-------
A permit was obtained from the Bay Area Air Quality
Management District in September 1989. The vapor
extraction system has been in operation since and
maintained volatile organic emission at below detection
limit.
Case Study D-2
AquaDetox® Groundwater Treatment,
Southern California
PROJECT:
CLIENT:
LOCATION:
PERFORMANCE
PERIOD:
ASSIGNMENT:
AquaDetox® Groundwater
Treatment
Confidential
Southern California
1988 - 1989
Design and Construction of
Groundwater Treatment System
A major manufacturing corporation retained AWD
Technologies, Inc., to design and construct a
groundwater remediation system to treat high
concentrations of PCE and TCE at a depth of 25 feet.
The company had planned to expand its existing
treatment system—one stripping tower with a carbon bed
adsorption unit—to four parallel trains with two stripping
towers each and a carbon adsorption unit for each train.
AWD significantly reduced the number of stripping
towers required to process the contaminated water by
using AquaDetox® technology. AWD's final design
uses three parallel trains with one stripping tower each
and a set of carbon adsorption units servicing all three
trains. AWD incorporated the existing stripping tower
and carbon adsorption unit into the design. The two
additional stripping towers~a conventional 300 gpm air
stripper and a 600 gpm AquaDetox® moderate vacuum
unit--and the new set of carbon adsorption units
completed the system.
Contaminated groundwater is piped to the treatment
system from off-site extraction wells near the head of
the plume three-fourths of mile west of the site and from
on-site extraction wells near the source of the
contamination. Contaminated air is purified with carbon
adsorption before being vented to the atmosphere. The
entire process is controlled by a state-of-the-art
instrumentation system.
Case Study D-3
AquaDetox® Vacuum Steam Stripping
System, King of Prussia, Pennsylvania
PROJECT:
CLIENT:
LOCATION:
PERFORMANCE
PERIOD:
ASSIGNMENT:
AquaDetox® Vacuum Steam
Stripping System
Ciba-Geigy Corporation
King of Prussia, Pennsylvania
1988-Present
Design and Construction of
Groundwater Treatment System
AWD Technologies, Inc., was retained by Ciba-Geigy
Corporation to permit, pilot test, design, construct, and
operate a vacuum steam stripping system to treat
contaminated groundwater at the Tyson's Dump
Superfund Site.
The Tyson's Dump site is an abandoned septic waste
and chemical waste disposal site reported to have
operated form 1976 to 1980 within a sandstone quarry,
approximately 200 yards from the Schuyhill River. In
September 1983, the site was added to the National
Priority List. Between January 1983 and August 1984,
EPA and its contractors conducted a series of
investigations primarily in what is referred to as the "On-
Site" area which includes two former lagoon areas.
Samples showed the presence of chemical contamination
within the soil column from the surface extending down
to bedrock.
In 1985, further investigation of the off-site area was
undertaken that included the underlying groundwater.
The groundwater was found to be contaminated with
organics. Major contaminants were 1,2,3-
58
-------
trichloropropane at levels exceeding 100,000 ppb, total
xylenes, aniline, and phenol.
As an interim remedial measure to clean the
groundwater, carbon adsorption units were installed at
the site. In 1988, the PRP committee retained AWD
Technologies, Inc., to design and construct a
groundwater treatment system to provide a long-term
solution.
AWD performed an AquaDetox® pilot simulation at
Dow Chemical's research laboratory in Midland,
Michigan. Based on the simulation, AWD designed a
500-gpm AquaDetox® vacuum steam stripping system
with recovered organics storage.
AWD began construction of the system in September
1989. Work included site work, foundations, building,
utility services, and the AquaDetox® stripping tower.
The system began operating in March 1990. AWD is
currently operating the system.
Case Study D-4
AquaDetox® Technology, Kalkaska,
Michigan
PROJECT:
CLIENT:
LOCATION:
ASSIGNMENT:
AquaDetox® Technology
The Dow Chemical Company
Kalkaska, Michigan
Design and Build Groundwater
Treatment System
The Dow Chemical Company selected the site of a
former Dowell facility in Kalkaska, Michigan, to apply
its AquaDetox® technology to a major groundwater
cleanup operation. The major contaminant was toluene
which had leaked from a faulty fitting. The leak had
proceeded an undetermined number of years, creating a
large plume. The initial concentration in the plume was
over 10 ppm toluene. AquaDetox® technology was
favored over traditional carbon bed adsorption because
of its high efficiency and low cost.
An AquaDetox® system was installed to treat
groundwater recovered from purge wells within the
plume. The system was set up to handle pumping rates
between 25 and 100 gpm and was generally operated at
30 to 40 gpm. The initial concentration of 10 ppm
toluene in 1984 is now down to less than 4 ppb,
approaching the laboratory detection limit. Some of the
purge wells are now being phased out as water quality
improves. The cost of treating the water by
AquaDetox® was about $1 to $2 per 1,000 gallons
compared to approximately $20 per 1,000 gallons for
carbon bed adsorption.
Case Study D-5
Integrated AquaDetox®/SVE Treatment
System, Burbank, California
PROJECT:
CLIENT:
LOCATION:
PERFORMANCE
PERIOD:
ASSIGNMENT:
AquaDetox®/SVE Treatment
System
Lockheed Aeronautical Systems
Company
Burbank, California
January - March 1990
Participate in Demonstration by
State of California, Department
of Health Services
This case study reviews AWD's integrated
AquaDetox®/SVE treatment system operating at the
Lockheed site over a six week period in early 1990. The
study was part of California's Toxic Substances Control
Program, alternative Technology Division under the
state's Department of Health Services. Their evaluation
included calculating the contaminant removal
efficiencies of the AquaDetox® and SVE systems
separately and determining an overall contaminant mass
balance on the integrated system.
During the course of the demonstration which began on
January 22, 1990 and ended on March 5,1990, influent
and effluent groundwater samples were collected weekly
and analyzed for VOCs and general water quality
parameters. Influent and effluent soil-gas samples were
collected biweekly and analyzed for VOCs. For the
purpose of conducting a mass balance, levels in the
59
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solvent storage tank, liquid phase separator's boot, and
soil-gas vapor/liquid separator tank were recorded before
and after the test.
The average overall contaminant removal efficiency of
the AquaDetox® system was 99.87 percent. Average
removal efficiencies for PCE and TCE were 99.98 and
99.94 percent, respectively. The average overall
contaminant removal efficiency of the SVE system was
99.65 percent with average removal efficiencies of 99.72
and 98.11 percent for PCE and TCE, respectively. The
overall total calculated recovery of contaminants was 6
percent higher than the actual quantity recovered.
Comparing the influent and effluent waters, there were
significant changes in chloride, sulfate, nitrate, and
boron. The effluent's temperature was approximately 6
to 9°C higher than the influent and had slightly lower
hardness and alkalinity than that of the influent water.
The effluent's pH was approximately 1 pH unit higher
than that of the influent. Total dissolved solids of the
effluent were lower than that of the influent.
60
•&U. S, GOVERNMENT PRINTING OFFICE: 199 1/55 1-564
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U.S. Envn-3;-;'::':rv:' p' ' ction ^'ency
Region 5, [ jcrj-y ;V'.-''1.J)
77 West Jackson :"- •• ' "srd, 12;.': Floor
Chicago, IL 6Gt. . JO
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