Introduction to Phytoremediation - US Environmental Protection

104 Pages·2000·3.67 MB·English

EPA/600/R-99/107
February 2000
Introduction to Phytoremediation
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
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Notice
The EPA through its ORD produced this document. It has been subjected to the Agency’s peer
and administrative review and has been approved for publication as an EPA document. Mention
of trade names or commercial products does not constitute endorsement or recommendation
for use.
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Foreword
The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation’s
land, air, and water resources. Under a mandate of national environmental laws, the Agency
strives to formulate and implement actions leading to a compatible balance between human
activities and the ability of natural systems to support and nurture life. To meet this mandate,
EPA’s research program is providing data and technical support for solving environmental prob-
lems today and building a science knowledge base necessary to manage our ecological re-
sources wisely, understand how pollutants affect our health, and prevent or reduce environmen-
tal risks in the future.
The National Risk Management Research Laboratory is the Agency’s center for investigation of
technicological and management approaches for reducing risks from threats to human health
and the environment. The focus of the Laboratory’s research program is on methods for the
prevention and control of pollution to air, land, water and subsurface resources; protection of
water quality in public water systems; remediation of contaminated sites and ground water; and
prevention and control of indoor air pollution. The goal of this research effort is to catalyze
development and implementation of innovative, cost-effective environmental technologies; de-
velop scientific and engineering information needed by EPA to support regulatory and policy
decisions; and provide technical support and information transfer to ensure effective implemen-
tation of environmental regulations and strategies.
This publication has been produced as part of the Laboratory’s strategic long-term research
plan. It is published and made available by EPA’s Office of Research and Development to assist
the user community and to link researchers with their clients.
E. Timothy Oppelt, Director
National Risk Management Research Laboratory
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Abstract
Phytoremediation is the name given to a set of technologies that use different plants as a
containment, destruction, or an extraction technique. Phytoremediation as a remediation tech-
nology that has been receiving attention lately as the results from field trials indicate a cost
savings compared to conventional treatments.
The U.S. EPA has a dual role in which it seeks to protect human health and the environment
associated with hazardous waste sites, while encouraging development of innovative technolo-
gies that might more efficiently clean up these sites.
This Introduction is intended to provide a tool for site regulators, owners, neighbors, and man-
agers to evaluate the applicability of phytoremediation to a site. This document defines terms
and provides a framework to understand phytoremediation applications. It is a compilation of
research and remediation work that has been done to date. The format is intended to be acces-
sible to EPA RPMs, state regulators, and others who need to choose between alternate tech-
nologies, as well for site owners, consultants, contractors, and students who are interested in
basic information. It is not a design manual, and is not intended to provide enough information
to choose, engineer, and install a phytoremediation application.
This work may also be used to help guide research, development, and regulation. Areas of
needed research have been identified. By compiling the published and unpublished work, re-
search repetition can be avoided, and areas of opportunity that need attention should be clear.
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Table of Contents
Foreword..................................................................................................................................iii
Acknowledgements..................................................................................................................xi
Chapter 1 Introduction...........................................................................................................1
1.1 Objectives ......................................................................................................1
1.2 Approach........................................................................................................1
1.3 Report Organization.......................................................................................1
Chapter 2 Overview of Phytoremediation...............................................................................3
2.1 Background.....................................................................................................3
2.2 Technical Considerations ................................................................................7
2.3 Economic Considerations ...............................................................................7
2.4 Regulatory Considerations..............................................................................9
2.5 Ecosystem Restoration................................................................................. 10
2.6 Current Research.......................................................................................... 12
Chapter 3 Evaluation of Phytoremediation Technologies...................................................... 14
3.1 Phytoextraction............................................................................................. 14
3.2 Rhizofiltration................................................................................................ 18
3.3 Phytostabilization.......................................................................................... 21
3.4 Rhizodegradation .......................................................................................... 23
3.5 Phytodegradation.......................................................................................... 28
3.6 Phytovolatilization......................................................................................... 31
3.7 Hydraulic Control........................................................................................... 34
3.8 Vegetative Cover Systems............................................................................ 35
3.9 Riparian Corridors/Buffer Strips..................................................................... 39
Chapter 4 Phytoremediation System Selection and Design Considerations......................... 41
4.1 Contaminated Media Considerations............................................................. 42
4.2 Contaminant Considerations ......................................................................... 43
4.3 Plant Considerations..................................................................................... 44
4.4 Site Considerations....................................................................................... 48
4.5 Treatment Trains............................................................................................ 51
4.6 Additional Information Sources..................................................................... 51
Chapter 5 Remedial Objectives, Treatability, and Evaluation................................................ 52
5.1 Remedial Objectives..................................................................................... 52
5.2 Treatability Studies ....................................................................................... 53
5.3 Monitoring for Performance Evaluation.......................................................... 56
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Contents (continued)
Chapter 6 Case Studies ......................................................................................................58
6.1 Edgewood Area J-Field Toxic Pits Site Aberdeen Proving Grounds
Edgewood, Maryland..................................................................................... 58
6.2 Carswell Site Fort Worth, Texas .................................................................... 60
6.3 Edward Sears Properties Site New Gretna, New Jersey ............................... 64
6.4 Bioengineering Management: U.S. Nuclear Regulatory Commission
Beltsville, MD ...............................................................................................67
6.5 Lakeside Reclamation Landfill Beaverton, Oregon......................................68
6.6 Alternative Landfill Cover Demonstration Sandia National Laboratories
Albuquerque, NM .......................................................................................... 70
Appendix A Glossary.............................................................................................................A-1
Appendix B Phytoremediation Database................................................................................B-1
Appendix C References.........................................................................................................C-1
Appendix D Common and Scientific Names of Referenced Plants ........................................D-1
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Figures
Figure 2-1. Mechanisms for phytoremediation......................................................................... 4
Figure 2-2. Example root depths. ............................................................................................6
Figure 3-1. Phytoextraction. .................................................................................................. 16
Figure 3-2. Rhizodegradation................................................................................................. 24
Figure 3-3. Phytodegradation................................................................................................. 29
Figure 3-4. Phytovolatilization. .............................................................................................. 32
Figure 3-5. Hydraulic control of contaminated plume............................................................. 34
Figure 3-6. Illustration of an Evapotranspiration (ET) cover. .................................................. 36
Figure 3-7. Phytoremediation cover evolution........................................................................ 37
Figure 6-1. Experimental Design ........................................................................................... 61
Figure 6-2. TCE Concentrations............................................................................................ 63
Figure 6-3. Site Map (Edward Sears Site) ............................................................................. 65
Figure 6-4. Sampling Grid (Edward Sears Site)..................................................................... 66
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Tables
Table 2-1. Phytoremediation Applications ..............................................................................5
Table 2-2. Root Depth for Selected Phytoremediation Plants.................................................6
Table 2-3. Phytoremediation at Superfund Sites ....................................................................8
Table 3-1. Phytoremediation Overview................................................................................. 15
Table 4-1. Phytoremediation Technologies Applicable to Different Contaminant Types1,2 43
............
Table 4-2. Plant Selection Process...................................................................................... 45
Table 5-1. Summary of Phytoremediation Technologies and Method of Contaminant Control52
Table 5-2. Experimental Factors for Testing in Treatability Studies....................................... 54
Table 5-3. Information Needed for a Pilot Treatability Study................................................. 55
Table 5-4. Summary of Monitoring Parameters.................................................................... 57
Table 6-1. Monitoring Approaches at the J-Field Site........................................................... 59
Table 6-3. Estimated Cost of Phytoremediation at the Carswell Site.................................... 63
Table 6-2. Average Concentrations of TCE, cis-DCE, and trans-DCE at Carswell Site......... 63
Table 6-4. Design Type and Completion Dates for the Experimental Covers. ....................... 67
Table 6-5. Summary of Run-off, Evapotranspiration, and Deep Percolation From the
Bioengineered Plots. ........................................................................................... 68
Table 6-6. Summary of Percolation and Precipitation Rates From
May 1997 Through March 1998 for the Six Cover Designs. ................................. 72
Table 6.7 Construction Costs for the Final Landfill Covers.................................................. 72
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Acronyms
AAP Army Ammunition Plant
ACAP Alternative Cover Assessment Program (U.S. EPA)
ALCD Alternative Landfill Cover Demonstration
ANOVA Analysis of Variance
APG Aberdeen Proving Grounds
ARARs Applicable or Relevant and Appropriate Requirements
ASTM American Society for Testing and Materials
BTEX Benzene, Toluene, Ethylbenzene, Xylenes
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
C Original Concentration
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DEPH Diethylhexylphthalate
DNAPL Dense Nonaqueous Phase Liquid
DOD Department of Defense
DOE Department of Energy
EPA Environmental Protection Agency
ERT U.S. EPA Emergency Response Team
FFDCA Federal Food, Drug, and Cosmetic Act
FIFRA Federal Insecticide, Fungicide, and Rodenticide Act
GC/MS Gas Chromatography/Mass Spectroscopy
HCB Hexachlorobenzene
K octanol-water partition coefficient
ow
LNAPL Light Nonaqueous Phase Liquid
MCL Maximum Contaminant Level
NPDES National Pollutant Discharge Elimination System
NPL National Priority List (Superfund)
NRMRL National Risk Management Research Laboratory
OSC On-Scene Coordinator
ORD U.S. EPA Office of Research and Development
OSWER U.S. EPA Office of Solid Waste and Emergency Response
PAH Polynuclear Aromatic Hydrocarbons
PCB Polychlorinated Biphenyls
PCE Perchloroethylene, tetrachloroethene
PCP Pentachlorophenol
PRP Potentially Responsible Party
PVC Polyvinyl Chloride
QA/QC Quality Assurance/Quality Control
RCRA Resource Conservation and Recovery Act
RD Remedial Design
RPM Remedial Project Manager
ROD Record of Decision
RTDF Remediation Technologies Development Forum
SITE Superfund Innovative Technology Evaluation Program (EPA)
TCA Tetrachloroethane
TCAA Trichloroacetic acid
TCE Trichloroethylene
TIO U.S. EPA Technology Innovation Office
TNT Trinitrotoluene
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Acronyms (continued)
TPH Total Petroleum Hydrocarbons
TSCA Toxic Substances Control Act
USDA U.S. Department of Agriculture
UXO Unexploded Ordinance
VOC Volatile Organic Compounds
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