EPA-600/8-85/008
June 1985
EPA GUIDE FOR
MINIMIZING THE ADVERSE ENVIRONMENTAL EFFECTS OF
CLEANUP OF UNCONTROLLED HAZARDOUS-WASTE SITES
Pacific Northwest Laboratory
Richland, Washington 99352
AD-89-F-2A115
Project Officer
Lawrence C. Raniere
Hazardous Materials Assessment Team
Environmental Research Laboratory
Corvallis, Oregon 97333
ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CORVALLIS, OREGON 97333
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DISCLAIMER
This manual describes scientifically relevant and important functional activities that
concern regional, state, and local authorities during the response to hazardous
substance releases. It is intended to convey technical recommendations only and not
to constitute agency policy. The manual should not supersede specific procedures
and documentation for quality assurance, chain-of-custody, and other requirements
addressed by Environmental Protection Agency regulations and policy guidance
documents currently in effect. The research described in this report has been funded
by the United States Environmental Protection Agency through interagency agree-
ment no. AD-89-F-2A115 to the United States Department of Energy. This report has
been subjected to the Agency's required peer and policy review.
This report was prepared as an account of work sponsored by an agency of the
United States Government. Neither the United States Government nor any agency
thereof, nor any of their employees, makes any warranty, expressed or implied, or
assumes any legal liability or responsibility for the accuracy, completeness, or use-
fulness of any information, apparatus, product, or process disclosed, or represents
that its use would not infringe upon privately owned rights. Reference herein to any
specific commercial product, process, or service by trade name, trademark, manu-
facturer, or otherwise, does not necessarily constitute or imply its endorsement,
recommendation, or favoring by the United States Government or any agency
thereof. The views and opinions of authors expressed herein do not necessarily state
or reflect those of the United States Government or any agency thereof.
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PREFACE
The Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA)
grants the President the authority to respond to releases of hazardous chemical substances that
imminently and substantially threaten public health or welfare, or the environment. The Act, which
establishes a $1.6-billion Superfund to finance response action, and which charges the Environmental
Protection Agency (EPA) with administering critical portions of the response program, was designed to
build on the existing environmental response authority given to EPA under Section 311 of the Clean
Water Act.
I n accordance with this mandate, the EPA is preparing a series of documents to assist state and regional
officials who are responsible for instituting cleanup actions at specific hazardous-waste sites. This guide
deals exclusively with environmental effects of remedial actions.
This guide supplies information and sources that an official needs to evaluate how to proceed at a
contaminated site. This document also can be used by management to assist in and overview staff
cleanup activities. Additionally, it is a training tool for persons who are new to the business of cleaning
up hazardous-waste sites. Finally, it is a resource for anyone who wishes to know more about the
cleanup of hazardous-waste sites.
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ACKNOWLEDGMENTS
Pacific Northwest Laboratory (PNL), operated by Battelle Memorial Institute for the U.S. Department of
Energy, prepared this document. The work was performed under Interagency Agreement No. AD-89-
F-2A115 with the U.S. Environmental Protection Agency (EPA) Office of Research and Development,
Corvallis Environmental Research Laboratory, Corvallis, Oregon. The work was performed at the
request of the EPA Office of Emergency and Remedial Response. Dr. Lawrence C. Raniere was the EPA
Project Officer and Dr. Richard A. Craig was the PNL Project Manager.
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CONTENTS
PREFACE iii
ACKNOWLEDGMENTS v
1.0 PURPOSE OF THIS GUIDE 1.1
2.0 HOW TO USE THIS GUIDE 2.1
3.0 SURFACE CONTROLS 3.1
3.1 SURFACE SEALING 3.1
3.2 GRADING 3.4
3.3 REVEGETATION 3.6
3.4 SURFACE-WATER DIVERSION AND COLLECTION 3.7
4.0 GROUND-WATER CONTROLS 4.1
4.1 IMPERMEABLE BARRIERS 4.1
4.2 PERMEABLE TREATMENT BEDS 4.3
4.3 GROUND-WATER PUMPING 4.4
4.4 INTERCEPTOR TRENCHES 4.5
4.5 BIORECLAMATION 4.5
5.0 LEACHATE COLLECTION AND TREATMENT 5.1
5.1 SUBSURFACE DRAINS 5.1
5.2 DRAINAGE DITCHES 5.2
5.3 LINERS 5.3
5.4 TREATMENT 5.4
6.0 GAS-MIGRATION CONTROLS 6.1
6.1 PIPE VENTS 6.1
6.2 TRENCH VENTS 6.2
6.3 GAS BARRIERS 6.3
6.4 GAS-COLLECTION SYSTEMS 6.4
6.5 GAS TREATMENT 6.4
6.6 GAS RECOVERY 6.5
7.0 DIRECT TREATMENT METHODS 7.1
7.1 EXCAVATION 7.1
7.2 HYDRAULIC DREDGING 7.2
7.3 LAND DISPOSAL 7.3
7.4 SOLIDIFICATION 7.4
7.5 ENCAPSULATION 7.5
7.6 IN SITU TREATMENT 7.6
7.6.1 In Situ Treatment—Solution Mining 7.6
7.6.2 In Situ Treatment—Neutralization/Detoxification 7.7
7.6.3 In Situ Treatment—Microbial Degradation 7.8
7.7 OTHER DIRECT TREATMENT METHODS 7.8
8.0 CONTAMINATED WATER AND SEWER LINES 8.1
8.1 IN SITU CLEANING 8.1
8.2 LEAK DETECTION AND REPAIRS 8.1
8.3 REMOVE AND REPLACE 8.2
VII
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9.0 CONTAMINATED SEDIMENTS , 9.1
9.1 MECHANICAL DREDGING 9.1
9.2 LOW-TURBIDITY HYDRAULIC DREDGING 9.2
9.3 DREDGE-SPOIL MANAGEMENT 9.3
9.4 REVEGETATION 9.4
10.0 REFERENCES 10.1
APPENDIX A
MONITORING SYSTEMS
A.1 GROUND-WATER MONITORING A.1
A.2 SURFACE-WATER MONITORING A.2
A.3 GAS-MONITORING A.3
APPENDIX B
WASTE-WATER TREATMENT MODULES
B.1 FLOW EQUALIZATION B.1
B.2 PRECIPITATION, FLOCCULATION, AND SEDIMENTATION B.I
B.3 BIOTREATMENT B.2
B.4 CARBON SORPTION B.3
B.5 ION EXCHANGE B.4
B.6 LIQUID ION EXCHANGE B.4
B.7 AMMONIA STRIPPING B.5
B.8 WET-AIR OXIDATION B.6
B.9 CHLORINATION B.6
ADDENDUM 1
FUGITIVE DUST AD-1.1
ADDENDUM 2
OTHER AIRBORNE EMISSIONS AD-2.1
VIII
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TABLES
3.0 SURFACE CONTROLS
3.1 Effects of Surface Controls: Surface Sealing (Capping) 3.2
3.2 Effects of Surface Controls: Grading 3.5
3.3 Effects of Surface Controls: Revegetation 3.6
3.4 Effects of Surface Controls: Surface-Water Diversion and Collection 3.7
3.1a Surface Controls:
3.1b Surface Controls
3.1c Surface Controls:
3.1d Surface Controls
3.1e Surface Controls
3.1f Surface Controls
3.1g Surface Controls
3.1h Surface Controls
3.1i Surface Controls
3.1j Surface Controls
3.2a Surface Controls
3.2b Surface Controls:
3.2c Surface Controls:
3.3a Surface Controls
3.4a Surface Controls
Surface Sealing—Soil Blending 3.9
Surface Sealing—Blending in Cements/Stabilizers 3.10
Surface Sealing—Soil Treating 3.11
Surface Sealing—Clay Capping 3.12
Surface Sealing—Portland Cement, Concrete, or Mortar 3.13
Surface Sealing—Bituminous Concrete Covering 3.14
Surface Sealing—Bituminous Membrane Covering 3.15
Surface Sealing—Sprayed Sulfur/Polyurethane Membranes 3.16
Surface Sealing—Poly (Vinyl Chloride, Ethylene, etc.) Covers 3.17
Surface Sealing—Industrial Residues 3.18
Grading—Slope Grading 3.19
Grading—Topsoil Hauling 3.20
Grading—Scarification or Contouring 3.21
Revegetation 3.22
Surface-Water Diversion and Collection—
Dikes and Berms 3.23
3.4b Surface Controls: Surface-Water Diversion and Collection—
Ditches, Diversions, and Waterways 3.24
3.4c Surface Controls: Surface-Water Diversion and Collection—
Terraces and Benches 3.25
3.4d Surface Controls: Surface-Water Diversion and Collection—
Chutes and Downspouts 3.26
3.4e Surface Controls: Surface-Water Diversion and Collection—
Levees 3.27
3.4f Surface Controls: Surface-Water Diversion and Collection—
Seepage Basins and Ditches 3.28
4.0 GROUND-WATER CONTROLS
4.1 Effects of Ground-Water Controls: Impermeable Barriers 4.1
4.2 Effects of Ground-Water Controls: Permeable Treatment Beds 4.3
4.3 Effects of Ground-Water Controls: Ground-Water Pumping 4.4
4.4 Ground-Water Controls: Interceptor Trenches 4.5
4.5 Ground-Water Controls: Bioreclamation 4.6
4.1a Ground-Water Controls: Impermeable Barriers—Slurry Walls 4.7
4.1b Ground-Water Controls: Impermeable Barriers—Grout Curtains 4.8
4.1c Ground-Water Controls: Impermeable Barriers—Sheet-Piling Cutoff Walls 4.9
4.2a Ground-Water Controls: Permeable Treatment Beds 4.10
4.3a Ground-Water Controls: Ground-Water Pumping 4.11
4.5a Ground-Water Controls: Bioreclamation 4.12
rx
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5.0 LEACHATE COLLECTION AND TREATMENT
5.1 Leachate Collection and Treatment: Subsurface Drains 5.1
5.2 Leachate Collection and Treatment: Drainage Ditches 5.2
5.3 Leachate Collection and Treatment: Liners 5.3
5.4 Leachate Collection and Treatment: Treatment 5.4
5.1a Leachate Collection and Treatment: Subsurface Drains 5.5
5.2a Leachate Collection and Treatment: Drainage Ditches 5.6
5.3a Leachate Collection and Treatment: Liners—Under-Waste Grouting 5.7
5.3b Leachate Collection and Treatment: Liners—Bentonite Slurry 5.8
6.0 GAS-MIGRATION CONTROLS
6.1 Effects of Gas-Migration Controls: Pipe Vents 6.1
6.2 Effects of Gas-Migration Controls: Trench Vents 6.2
6.3 Effects of Gas-Migration Controls: Gas Barriers 6.3
6.4 Effects of Gas-Migration Controls: Gas-Collection Systems 6.4
6.5 Effects of Gas-Migration Controls: Gas Treatment 6.5
6.6 Effects of Gas-Migration Controls: Gas Recovery 6.6
6.1a Gas-Migration Controls: Pipe Vents 6.7
6.2a Gas-Migration Controls: Trench Vents 6.8
6.3a Gas-Migration Controls: Gas Barriers 6.9
6.4a Gas-Migration Controls: Gas-Collection Systems 6.10
6.5a Gas-Migration Controls: Gas Treatment—Flares 6.11
6.5b Gas-Migration Controls: Gas Treatment—Afterburners 6.12
6.5c Gas-Migration Controls: Gas Treatment—Carbon Sorption 6.13
6.6a Gas-Migration Controls: Gas Recovery 6.14
7.0 DIRECT-TREATMENT METHODS
7.1 Direct-Treatment Methods: Excavation 7.1
7.2 Direct-Treatment Methods: Hydraulic Dredging 7.3
7.3 Direct-Treatment Methods: Land Disposal 7.4
7.4 Direct-Treatment Methods: Solidification 7.5
7.5 Direct-Treatment Methods: Encapsulation 7.6
7.6.1 Direct-Treatment Methods: In Situ Treatment—Solution Mining 7.6
7.6.2 Direct-Treatment Methods: In Situ Treatment—Neutralization/Detoxification 7.7
7.6.3 Direct-Treatment Methods: In Situ Treatment—Microbial Degradation 7.8
7.7 Direct-Treatment Methods: Others 7.9
7.1a Direct-Treatment Methods: Excavation 7.11
7.2a Direct-Treatment Methods: Hydraulic Dredging 7.12
7.3a Direct-Treatment Methods: Land Disposal—Landfilling 7.13
7.3b Direct-Treatment Methods: Land Disposal—Surface Impoundment 7.14
7.3c Direct-Treatment Methods: Land Disposal—Land Application 7.15
7.4a Direct-Treatment Methods: Solidification—Cement-Based Methods 7.16
7.4b Direct-Treatment Methods: Solidification—Lime-Based Methods 7,17
7.4c Direct-Treatment Methods: Solidification—Thermoplastic-Based Method 7.18
7.4d Direct-Treatment Methods: Solidification—Organic-Polymer-Based Methods 7.19
7.4e Direct-Treatment Method.^: Soiidinca'ion— Self-Cementing Methods 7.20
7.4f Direct-Treatment Methods: Solidification—Gasification Methods 7.21
7.5a Direct-Treatment Method^: Encapsulates 7.22
7.6a Direct-Treatment Methods: In Siti- Treatment—Solution Mining 7.23
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7.6b Direct-Treatment Methods: In Situ Treatment—Neutralization/Detoxification 7.24
7.6c Direct-Treatment Methods: In Situ Treatment—Microbial Degradation 7.25
7.7a Direct-Treatment Methods: Other Direct Treatment Methods—
Molten-Salt Process 7.26
7.7b Direct-Treatment Methods: Other Direct Treatment Methods—
Plasma-Reduction Process 7.27
8.0 CONTAMINATED WATER AND SEWER LINES
8.1 Contaminated Water and Sewer Lines: In Situ Cleaning 8.1
8.2 Contaminated Water and Sewer Lines: Leak Detection and Repairs 8.2
8.3 Contaminated Water and Sewer Lines: Remove and Replace 8.2
8.1a Contaminated Water and Sewer Lines: In Situ Cleaning 8.5
8.2a Contaminated Water and Sewer Lines: Leak Detection and Repairs 8.6
8.3a Contaminated Water and Sewer Lines: Remove and Replace 8.7
9.0 CONTAMINATED SEDIMENTS
9.1 Contaminated Sediments: Mechanical Dredging 9.1
9.2 Contaminated Sediments: Low-Turbidity Hydraulic Dredging 9.2
9.3 Contaminated Sediments: Dredge-Spoil Management 9.3
9.4 Contaminated Sediments: Revegetation 9.4
9.1a Contaminated Sediments: Mechanical Dredging 9.7
9.2a Contaminated Sediments: Low Turbidity—Hydraulic Dredging 9.8
9.3a Contaminated Sediments: Dredge-Spoil Management—Dewatering and Transport 9.9
9.3b Contaminated Sediments: Dredge-Spoil Management—Storage and Disposal 9.10
9.3c Contaminated Sediments: Dredge-Spoil Management—Separation 9.11
9.4a Contaminated Sediments: Revegetation 9.12
APPENDIX A
MONITORING SYSTEMS
A.I Monitoring Systems A.1
A.la Monitoring Systems: Ground-Water Monitoring A.3
APPENDIX B
WASTE-WATER TREATMENT
B.1 Waste-Water Treatment: Flow Equalization B.1
B.2 Waste-Water Treatment: Precipitation, Flocculation, and Sedimentation B.2
B.3 Waste-Water Treatment: Biotreatment B.3
B.4 Waste-Water Treatment: Carbon Sorption B.4
B.5 Waste-Water Treatment: Ion Exchange B.4
B.6 Waste-Water Treatment: Liquid Ion Exchange 8.5
B.7 Waste-Water Treatment: Ammonia Stripping B.5
B.8 Waste-Water Treatment: Wet-Air Oxidation B.6
B.9 Waste-Water Treatment: Chlorination B.7
XI
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B.1a Waste-Water Treatment Modules:
B.2a Waste-Water Treatment Modules:
B.3a Waste-Water Treatment Modules:
B.4a Waste-Water Treatment Modules:
B.5a Waste-Water Treatment Modules:
B.6a Waste-Water Treatment Modules:
B.7a Waste-Water Treatment Modules:
B.8a Waste-Water Treatment Modules:
B.9a Waste-Water Treatment Modules:
Flow Equalization B.9
Precipitation, Flocculation, and Sedimentation B.10
Biotreatment B.11
Carbon Sorption B.12
Ion Exchange B.13
Liquid Ion Exchange B.14
Ammonia Stripping B.15
Wet-Air Oxidation B.16
Chlorination B.17
ADDENDUM 1
FUGITIVE DUST
AD.1 Fugitive-Dust Control Costs AD-1.2
FIGURES
1.0 PURPOSE OF THIS GUIDE
1.1 Steps in the Cleanup Process 1.1
3.0 SURFACE CONTROLS
3.1 Example of Lateral Movement of Off-Site Recharge 3.4
XII
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1.0 PURPOSE OF THIS GUIDE
This document is intended to guide on-site decision authorities in appraising and analyzing potential
environmental consequences of any given alternative for cleanup of an uncontrolled hazardous-waste
site. As such, this guide focuses on the "Analysis of Alternatives" step of the cleanup process (Figure 1.1).
The Environmental Protection Agency (EPA) has published a "Handbook for Remedial Action at Waste
Disposal Sites" (EPA 625/6-82-006June 1982), henceforth referred to as EPA 1982. That manual presents
information on technologies which may be applicable to specific problems of controlling hazardous
wastes at disposal sites. EPA 1982 is a comprehensive treatise on the many corrective practices used to
clean up hazardous-waste sites and spills. EPA 1982 provides technical assistance to Federal, state, and
local agencies in identifying and analyzing cleanup alternatives; it does not, however, cover any
technology exhaustively, nor does it cover all topics that must be considered in analyzing alternative
cleanup actions.
A critical factor in the analysis of treatment options is the cost-effectiveness of the various alternatives.
An important element in the cost-effectiveness evaluation is consideration of the consequences of the
various treatment options because negative secondary effects often may result from well-intentioned
and conducted treatment measures.
This guide is structured to be used in conjunction with EPA 1982. The treatment options described in
EPA 1982 that may be used as components of a cleanup strategy are summarized here in terms of their
potentially adverse environmental effects. To the extent that specific information is available, that
informa'Jon is presented and documented. In cases where specific information is not available (i.e.,
where current knowledge is sparse, unconfirmed, or lacking), a subjective appraisal, with appropriate
qualification, is included. The remedial actions are discussed only in sufficient detail to identify what
adverse effects each may cause. EPA 1982 describes the remedial actions more fully.
Discovery
Stabilization
Preliminary
Survey
Decision for
Further Response
Site
Characterization
Assessment
Planned Response
Identification of
Alternatives
•/Analysis of v-
. Alternatives *
Selection of
Remedial Action
FIGURE 1.1 Steps in the Cleanup Process
T.I
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2.0 HOW TO USE THIS GUIDE
Before a decision maker uses this guide, he/she should have identified a preliminary list of remedial
actions (during the "Identification of Alternatives" step shown in Figure 1.1). These alternatives will
have been chosen for their potential to meet cleanup criteria at the site, taking into account the specific
characteristics of the site.
The basis for and principles of each of the potential technologies are discussed in EPA 1982. Also
discussed in that document is the basis for estimating the cost of each alternative. Because this
companion document will be used in conjunction with EPA 1982, those considerations are not
reiterated here.
This guide provides information on the potential adverse environmental effects associated with each
alternative. It addresses qualitatively the projected significance or probability of the effect, the extent
to which it may be avoided or mitigated, its persistence (during the construction phase only or
persisting into the indefinite future), and whether the effect is related to hazardous matter or unrelated
to the presence of hazardous material (a nuisance effect). Because any adverse effects will be con-
trolled by site-specific factors, the discussion here is generic. It is intended to stimulate consideration of
each of the possible effects; it is not intended to be all inclusive.
The organization of this guide parallels that of EPA 1982. That is, in EPA 1982, technical aspects of surface
sealing are discussed in Section 3.1; in this guide, environmental aspects of surface sealing are likewise
discussed in Section 3.1. Thus, the sections of EPA 1982 correspond on a one-to-one basis with those
here. This document has two additional sections, Addendum 1 and Addendum 2, which do not
correspond to any sections in EPA 1982. Since EPA 1982 has appendices (with corresponding appen-
dices in this document), the supporting sections here have been called addenda.
Summary tables are provided for each technology to describe potential environmental effects to
ground-water quantity/movement, ground-water quality, surface-water quantity/movement,
surface-water quality, air quality, soils/geology, biota, human health and safety, and resource com-
mitment. Each table is designed to give the reader a quick reference to estimate the level of concern
about the effect to each medium as reflected by a subjective probability for its occurrence (from
"highly probable" to "no effect predicted"); the duration of the effect (short term—lasting only during
the remedial activity—or long term—persisting beyond the period of the activity); the extent to which
it is reversible, preventable, or mitigable; and whether the effect is related to the hazardous matter at
the site or whether it is an impact that would occur on any site on which the activity is performed.
For each specific activity, good engineering practice (GEP) tables are provided and referenced at the
end of each section. These GEP tables provide a brief description of the nature of the potential adverse
environmental effect associated with that activity and a brief description of the mitigative action that
may be taken to prevent, correct, or minimize each effect.
The text accompanying each table contains a more complete discussion of the potential effects, a
description of mitigation or avoidance measures, and, where applicable, their costs (information is
incorporated by reference where possible). Because this guide is a companion to EPA 1982, each
section is intended to support the corresponding section of EPA 1982. As a result there is considerable
repetition from section to section of this guide.
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3.0 SURFACE CONTROLS
Surface controls are measures undertaken to prevent surface waters and wind from causing off-site
transport of hazardous matter. The methods discussed are surface sealing (capping), grading, revegeta-
tion, and surface-water diversion and collection.
3.1 SURFACE SEALING
Surface sealing (or capping) is a method for covering hazardous-waste disposal sites to prevent
surface-water infiltration, control wind and water erosion, and prevent the migration to the surface of
contaminants, waste, or volatile matter (EPA 1982). Capping contaminated surface soil will also reduce
the release of materials into the atmosphere. Various weather elements can act to enhance release
rates. Paniculate releases increase during high winds and during rainfall. Gaseous releases can be
increased depending on surface temperature, moisture, and as the result of changes in atmospheric
pressure. Depending on the contaminant composition, the capping measure will reduce atmospheric
releases of dust and vapor. The potential effects associated with the use of surface-sealing measures are
summarized in Table 3.1 and described in the good engineering practice tables, Tables 3.1a-j, at the end
of this section.
Because the areas covered by uncontrolled hazardous-waste sites are generally small compared to the
total recharge zone for near-surface aquifers, surface sealing is not expected to significantly affect
ground-water quantity and/or ground-water movement. Likewise, because capping is intended to
prevent infiltration, it is not projected to negatively affect ground-water quality. (The overwhelming
effect should be positive because it reduces transport of the hazardous material into the aquifer.) If,
however, industrial residues that contain toxic or objectionable materials are used for capping,
ground-water quality could be negatively affected. Fly ash, bottom ash and slag, furnace slag, and
incinerator residue all contain heavy metals and other objectionable materials. Dredge materials often
contain significant quantities of toxic and other objectionable materials. Nontoxic industrial sludges
and composted sewage sludge may contain significant quantities of objectionable materials (such as
nitrates, in the case of sewage sludge). If the cover materials contain objectionable or toxic materials
and if these materials can find their way into the ground water, they can degrade ground-water quality.
Additionally, the use of industrial residues as capping material may cause increased release of toxic
contaminants; reaction of chemicals in water that has passed through the industrial residue with the
hazardous waste may mobilize the waste. These potential effects of the use of industrial residues can be
minimized by careful selection and testing of candidate capping materials.
Capping of a facility and diverting run-on and runoff waters may affect ground water if insufficient care
is taken in disposing of the waters. Lateral movement of infiltrating ground water must be considered in
the design of capping activities (Figure 3.1). Protection of the facility must be carried out to some
distance from the waste-storage area to prevent any infiltration of diverted waters into the waste area.
If surface sealing functions as designed, it will affect surface-water movement by diverting waters (that
would otherwise infiltrate) off site. In turn, this increased runoff to off-site locations could potentially
cause off-site erosion and degrade water quality by carrying soil to surface-water bodies. If off-site
erosion occurs, it could remove habitat for terrestrial biota. If surface-water quality is degraded as a
result of off-site erosion, aquatic habitat will be degraded. Additionally, if the short-term runoff results
in silting of the receiving waters, a short-term impact on biota in receiving waters can be expected. A
small amount of silt can have a significant effect on the aquatic ecosystem if fish spawning or insect
reproduction cycles are affected. Each of these possible negative effects may be avoided by managing
the runoff through appropriate grading and/or off-site surface-water controls. Off-site surface-water
controls may include diversion ditches or infiltration basins used in conjunction with revegetation.
Design and cost considerations for these are discussed in EPA 1982 (Sections 3.3 and 3.4).
3.1
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TABLE 3.1. Effects of Surface Controls: Surface Sealing (Capping)
Ground-Water
Surf ace-Water
Public
Health/ Resource
Movement/ Movement/ Air Soils/
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
Soil Blending 9HPR
Blending in
Cements/
Stabilizers
Soil Treating
• lime/fly ash
• chemical
dispersants/
swell
reducer
Clay Capping
Portland
Cement,
Concrete, or
Mortar
Bituminous
Concrete
Covering
Bituminous
Membrane
Covering
Sprayed
Sulfur/
Polyurethane
Membranes
Poly (VC,
Chlor. L, etc.)
Covers
OHPR
0>HPR
OHPR
9HPR
9HPR
9HPR
OHPR
(1HPR
»HPR
ONPR «NPR «NSR 9NPR 9HPR 9HPR
— — OHPR — 9NPR —
»NPR «NPR »NSR ONPR »HPR 0>HPR
— — 9HPR — <»NPR —
»NPR «NPR «NSR ONPR 0)HPR 0>HPR
— — »HPR — ONPR —
»NPR «NPR »NPR 0>HPR 0>HPR
— — (1HPR — «NPR —
— — ONSR — — —
»NPR »NPR »NSR OJNPR «NPR —
»NPR »NPR »NSR 0>NPR ONPR —
»NPR «NSI »NPR 0>NPR
— «NSR — —
dNPR
NPR
NSI
NSR
ONPR —
ONPR «NPR «NSR »NPR «NPR —
»NPR »NPR »NSR 0>NPR ONPR —
• = Highly Probable 3 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
3.2
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Ground-Water
TABLE 3.1. (Continued
Surface-Water
Public
Movement/
Quality Quantity Quality
Industrial
Residues
• fly ash OHPR — ONPR
• bottom ash/
slag OHPR — <1NPR
• furnace slag/
incinerator
residue OHPR — ONPR
• mine
overburden OHPR — ONPR
• dredge
material OHPR — ONPR
• industrial
sludges
(nontoxic) OHPR — ONPR
• compacted
sewage
sludge OHPR — ONPR
ONPR
• = Highly Probable O = Probable
N = Nuisance H = Hazardous
S = Short-term (construction phase only)
R = Reversible (or mitigable)
NB: Multiple entries in a category indicate that
Movement/ Air
Quantity Quality
• NPR • NSR
• NPR • NSR
• NPR • NSR
• NPR • NSR
• NPR • NSR
• NPR • NSR
• NPR • NSR
0 =
P =
1 =
several different types
Soils/ Health/ Resource
Geology Biota Safety Commitments
ONPR ONPR — —
ONPR ONPR — —
ONPR ONPR — —
ONPR ONPR — —
ONPR ONPR — —
ONPR ONPR — —
ONPR ONPR — —
: Improbable
: No significant effects predicted
: Persistent (beyond construction phase)
Irreversible (unmitigable)
of effects are foreseen as possible.
3.3
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do
Runoff
Recharge Cone
of Impression
FIGURE 3.1. Example of Lateral Movement of Off-Site Recharge
Blending brought-in soil with existing soil or blending of additives to the existing soil to create capping
material will raise fugitive dust. If the surface soil is contaminated with a hazardous material, the
fugitive dust may represent both a hazardous air contaminant and an on-site human health and safety
hazard. If the surface is uncontaminated, then the fugitive dust represents a nuisance factor. If the
fugitive dust is uncontaminated, it can be reduced by water spraying and other measures (see Adden-
dum 1). Application of water or other matter for dust control requires careful planning and monitoring
to assure that excess water is not applied or that the material being used for dust control does not
interact with the capping medium. The application of excess water can result in increased levels of
saturation of the capping material and subsequent increases in the hydraulic conductivity of those
materials. Imprudent selection of dust-control liquids could reduce the effectiveness of the cap.
The use of bituminous concrete or bituminous membrane coverings fabricated on site will result in the
emission of heavy hydrocarbons. This is an unavoidable effect of use of this technology and only occurs
during the period of construction. The effect of these emissions is not significant, in most instances
causing only a local and temporary nuisance factor.
3.2 GRADING
Grading is a general term for techniques used to reshape the surface of covered landfills in order to
manage surf ace-water infiltration and runoff while controlling erosion (EPA 1982). The potential effects
associated with the use of grading are summarized in Table 3.2 and described in the good engineering
practice tables. Tables 3.2a-c, at the end of this section.
Grading consists of a series of construction activities that can be conveniently divided into three
groups: slope grading, topsoil haulage, and scarification or contouring. Because the general purpose
of grading activities is to divert surface water from the site, these are not expected to cause significant
negative effects to ground-water quantity, ground-water movement, or ground-water quality.
During the construction phase and before new vegetation has been established on the site, surface
grading and scarification or contouring can leave soils open to erosion. Loose soil provides a potential
source of particulates that could be suspended in surface water. If the eroded soils are contaminated
with hazardous materials, surface waters potentially could be contaminated with hazardous materials.
These effects can be mitigated by using runoff controls and sedimentation basins during construction
activities (see Section 3.4 of EPA 1982).
3.4
-------
TABLE 3.2. Effects of Surface Controls: Grading
Ground-Water Surface-Water
Soils/
Slope Grading
Quality
—
Movement/
Quantity
—
Quality
3HPR
ONSR
Movement/
Quantity
• NPR
Air
Quality
(1HPR
ONSR
Public
Health/
Resource
Geology Biota Safety Commitments
— 3NPR 3HPR —
— OHPR — —
Topsoil Haulage
Scarification or
Contouring
»NSR
N
S
R
NB:
= Highly Probable 3 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
'NSI
— ONSI
ONSR — ONSR —
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
Slope grading is intended to change the patterns of surface-water movement. Changing water move-
ment patterns may change local drainages. This could cause adverse effects by reducing or increasing
flow in small streams, possibly causing flooding in the latter case. The potential for this effect should be
considered and surface-water diversion and collection measures used if applicable. Reduced flow may
be unavoidable.
Slope grading and scarification, being construction-related activities, can potentially raise fugitive dust.
If the soil moved during slope grading is contaminated with hazardous materials, the fugitive dust may
carry site contaminants off site. These fugitive dusts can affect nearby terrestrial biota. The raising of
fugitive dust during construction-related activities can be reduced by the use of water spray and other
measures (see Addendum 1).
Hauling topsoil increases traffic along neighboring roads. This traffic will raise fugitive dust and
increase noise. These effects are irremediable except that haulage activities may be conducted during
the hours of the day when these effects are least noticeable.
If slope grading reduces surface-water discharge to small creeks by diverting flow to another drainage,
the reduction in flow of that water body can negatively affect the biota in that water body. Additionally,
if the short-term runoff results in silting of the receiving waters, a short-term impact on biota in
receiving waters can be expected. A small amount of silt can have a significant effect on the aquatic
ecosystem if fish spawning or insect reproduction cycles are affected. If the silt is contaminated with a
nondegradable material, then the effect can be expected to be persistent. Likewise, if. during the
period of the scarification or contouring activities, sediment loading to receiving waters is increased.
negative impacts on biota in receiving waters can be expected. These effects on biota can be mitigated
using the same measures used to prevent surface-water quality from deteriorating.
If slope grading transports hazardous material off site via either fugitive dust or sediment, this presents
a potential health and safety hazard for off-site populations. This potential negative effect can be
mitigated by using the same measures used to control fugitive dusts and surface-water sediments.
Topsoil haulage, by increasing local traffic, presents a traffic safety hazard for the communities through
which the traffic passes. This is an irremediable but short-term negative effect.
3.5
-------
3.3 REVECETATION
Revegetation establishes a vegetative cover to stabilize the surface of a hazardous-waste site. Revegeta-
tion can also be useful in controlling infiltration by increasing transpiration (Beedlow 1984). Proper
revegetation will preclude the establishment of deep-rooted species, the presence of which could
reduce the effectiveness of other control measures. Thus, revegetation can serve multiple uses as part
of a remedial alternative. The potential effects associated with the use of revegetation measures are
summarized in Table 3.3 and described in the good engineering practice table, Table 3.3a, at the end of
this section.
The vegetative cover should not adversely affect ground water or surface water. However, fertilizers
and/or other agricultural chemicals (e.g., herbicides) that may be applied to help establish the
vegetation can infiltrate to ground water or run off into surface waters. Species should be selected
carefully and agricultural chemicals applied judiciously to avoid contamination.
The type of rooting system of the plants must also be considered. Many plant species have intrusive
roots which might penetrate the cap and breach the seal. If the seal is breached, hazardous materials
may be released, resulting in potential negative effects on ground-water quality, surface-water quality,
soils, biota, and human health and safety. Penetrating roots may take up the hazardous materials and
transport them to the surface; breakdown of these roots provides new pathways for the infiltration of
water. These effects can be mitigated by restricting the species used for revegetation to those with
shallow roots and species that are intensely competitive with deep-root native species. A layer of
herbicide between the cap and the surface can be an effective barrier to root penetration by deep-
rooted species while permitting establishment of shallow-rooted species.
If the soil on which the vegetative cover is contaminated or if the plant roots penetrate to a contami-
nated zone, the plants may pick up and incorporate hazardous matter. To guard against public
exposure via this route, the vegetative cover should not be used for food for humans or livestock. A
long-term monitoring program should continue to examine the vegetative cover for uptake of
hazardous matter.
Additionally, revegetation as an element in a remedial action alternative contains the possibility of
inadvertant introduction of noxious or poisonous weeds that contaminate the seeds. This possible
negative effect can be minimized by specification of the seed content and source region (seed should
not be imported from a region where a specific weed species is known to thrive) and by careful
follow-up inspection of the site. In some cases, revegetation with native communities may be the best
management practice.
TABLE 3.3. Effects of Surface Controls: Revegetation
Ground-Water Surf ace-Water
Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
Fertilization
Revegetation
3NPR
»HPR
(1NSR
3HPR
»HPR OHPR
— ONPI
3HPR
N
S
R
NB:
= Highly Probable O = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
3.6
-------
3.4 SURFACE-WATER DIVERSION AND COLLECTION
Surface-water diversion and collection structures are used to provide short-term or permanent mea-
sures to isolate hydrologically waste sites from surface inputs (EPA 1982). These structures are divided
into the following categories: dikes and berms; ditches, diversions and waterways; terraces and
benches; chutes and downpipes; levees; seepage basins and ditches (recharge basins); and sedimenta-
tion basins/ponds. Dikes, berms, ditches, chutes, and downspouts are temporary structures to manage
water during remediation activities; diversions, waterways, terraces, and benches are permanent
structures or temporary structures, and seepage basins and ditches, levees, and sedimentation basins
and ponds are permanent structures. The potential effects associated with the use of surface-water
diversion and collection measures are summarized in Table 3.4 and described in the good engineering
practice tables, Tables 3.4a-g, at the end of this section.
Surface-water diversion and collection structures are not expected to significantly affect ground-water
quality or quantity. However, dikes and berms and some terraces and benches are installed upgradient
of the site while ditches, diversions, and waterways will skirt the site. These structures could induce
recharge through the waste matter. This can be avoided by developing a clear understanding of the
local hydrology and recharge before deciding to install diversion and collection systems.
TABLE 3.4. Effects of Surface Controls: Surface-Water Diversion and Collection
Terraces and
Benches
Chutes and
Downpipes
Levees
Seepage Basins
and Ditches
(recharge basins)
Sedimentation
Basins and
Ditches
Sedimentation
Basins/Ponds
Ground-Water
Movement/
Surface-Water
Movement/ Air
Soils/
Public
Health/
Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
Dikes and Berms O HSR
Ditches,
Diversion,
and Waterways 3 H PR
OHSR
OHPR
OHPR
ONSR
ONPR
ONSR
ONSR
ONSR
ONSR
ONSR
ONSR
ONSR
ONSR
OHPI
ONSR
ONPR
ONSR
ONPR
ONSR
ONSR
ONPR
• NSR — ONPR —
• NSR — ONPR ONPR
• NSR — ONPR —
• NSR — ONPR —
• NSR — ONPR ONPR
ONSR —
• NSR —
• NSR —
ONPR ONPR
ONPR ONPR
ONSR —
N
S
R
NB:
= Highly Probable O = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
3.7
-------
ic use of surface-watei Jivefiicjn and colloctirr. ilfL'i_tu?t.' is not expected to affect surface-water
uality except during the construction of these structures, "efore the building material is stabilized,
jnoff may carry increased amounts of sediment. If the sediment reaches receiving waters, it wii!
adversely affect biota by reducing habitat. Additionally, if the short-term runoff results in silting of the
receiving waters, a short-term impact on biota in receiving waters can be expected. A small amount of
silt can have a significant effect on the aquatic ecosystem if fish spawning or insect reproduction cycles
are affected. This can be mitigated via the early installation of sedimentation basins or ponds for which
this effect is self-mitigating. A possible, but unlikely, negative effect of the use of sedimentation basins
or ponds to prevent the transport of contaminated sediments off site would occur from a greater-than-
design flood that could release the trapped contaminated sediments into the environment. This effect
is unavoidable, but very unlikely.
The use of surface-water diversion and collection methods, by design, affects the destination of
overland flow. This can result in adverse effects on wildlife if the flow to streams or wetlands is
significantly reduced. The use of levees to prevent floodwaters from encroaching on the hazardous-
waste site will tend to increase flood potential immediately upstream or downstream. These are
unavoidable adverse effects of this technology.
During the construction of these structures or decommissioning of temporary structures, fugitive dust
may be raised. Fugitive-dust emissions may be reduced by the use of water spraying and other
techniques (see Addendum 1).
In addition to effects on aquatic biota from increased sediment loadings during construction, ditches,
diversions and waterways; levees; and seepage basins and ditches will catch water in a way that will
provide breeding grounds for insects. Low spots in ditches, diversions and waterways can trap small
pockets of water. Seepage basins and ditches generally hold standing water, especially after use has led
to some silting. Levees can prevent runoff from reaching receiving waters, but the runoff will pond on
the uphill side of the levee providing a potential breeding ground for insects. Creation of insect
breeding grounds can be minimized by maintenance activities. Ditches, diversions and waterways
should be inspected so that ponding can be found and corrected. When seepage basins have silted
such that water is retained for extended periods of time, these must be rehabilitated. Upslope
collection areas should be designed in tandem with the levee and pumped regularly. An additional
potential negative effect of seepage basins and ditches is that humans and other biota may be trapped
in them if the sides are too steep and the structures too deep. For safety, these should be fenced. To
prevent impacts on biota, the sides should not be so steep as to trap small animals. Small animal control
should be an element of diversion measure management because animal burrows can compromise the
integrity of earthern barriers, which can result in failure.
3.8
-------
TABLE 3.1a. Surface Controls: Surface Sealing—Soil Blending
Affected Area Effect Mitigation Measure
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
if surface soil is contaminated, blending opera-
tions may raise contaminated fugitive dusts
Soils/Geology increased runoff as a result of capping can
cause erosion
Biota fugitive dust (contaminated or uncontami-
nated) from capping can affect nearby biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
Public Health contaminated fugitive dust from capping
or Safety activities can carry hazardous material off site
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
incorporate surface-water diversion and
collection measures with revegetation as
appropriate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorporate
surface-water diversion and collection mea-
sures as appropriate (see EPA 1982, Sections 3.3
and 3.4); decreased flow may be unavoidable
fugitive-dust control (see Addendum 1)
control of contaminated fugitive dust (see
Addendum 1)
incorporate surface-water diversion and
collection measures with revegetation as
appropriate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
see air quality above
3.9
-------
TABLE 3.1b. Surface Controls: Surface Sealing—Blending in Cements/Stabilizers
Affected Area
Effect
Mitigation Measure
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
if surface soil is contaminated, blending oper-
ations may raise contaminated fugitive dusts
Soils/Geology increased runoff as a result of capping can
cause erosion
Biota fugitive dust (contaminated or uncontami-
nated) from capping can affect nearby biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
Public Health contaminated fugitive dust from capping
or Safety activities can carry hazardous material off site
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
incorporate surface-water diversion and
collection measures with revegetation as
appropriate (see EPA 1982, Sections 3.3 and
3.4)
if increased flow will be a problem, incorporate
surface-water diversion and collection mea-
sures as appropriate (see EPA 1982, Sections 3.3
and 3.4); decreased flow may be unavoidable
fugitive-dust control (see Addendum 1)
control of contaminated fugitive dust (see
Addendum 1)
incorporate surface-water diversion and
collection measures with revegetation as
appropriate (see EPA 1982, Sections 3.3 and
3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
see air quality above
3.10
-------
Table 3.1c. Surface Controls: Surface Sealing—Soil Treating
Affected Area
Effect
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
if surface soil is contaminated, blending oper-
ations may raise contaminated fugitive dusts
Soils/Geology increased runoff as a result of capping can
cause erosion
Biota fugitive dust (contaminated or uncontami-
nated) from capping can affect nearby biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
Public Health contaminated fugitive dust from capping
or Safety activities can carry hazardous material off site
Mitigation Measure
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
incorporate surface-water diversion and
collection measures with revegetation as
appropriate (see EPA 1982, Sections 3.3 and
3.4)
if increased flow will be a problem, incorporate
surface-water diversion and collection mea-
sures as appropriate (see EPA 1982, Sections 3.3
and 3.4); decreased flow may be unavoidable
fugitive-dust control (see Addendum 1)
control of contaminated fugitive dust (see
Addendum 1)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
see air quality above
3.11
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TABLE 3.1d. Surface Controls: Surface Sealing—Clay Capping
Affected Area
Effect
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
Soils/Geology increased runoff as a result of capping can
cause erosion
Mitigation Measure
Biota
fugitive dust from capping can affect nearby
biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
understand ground-water hydrology in suffi-
cient detail to know fate of waters
incorporate surface-water diversion and
collection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorpo-
rate surface-water diversion and collection
measures as appropriate (see EPA 1982, Sec-
tions 3.3 and 3.4); decreased flow may be
unavoidable
fugitive-dust control (see Addendum 1)
incorporate surface-water diversion and
collection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
3.12
-------
TABLE 3.1e. Surface Controls: Surface Sealing—Portland Cement, Concrete, or Mortar
Affected Area
Effect
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surf ace-Water runoff from soils disturbed during capping
Quality activities can carry sediment to receiving
waters
increased runoff as a result of capping can
cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
Soils/Geology increased runoff as a result of capping can
cause erosion
Biota
fugitive dust from capping can affect nearby
biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
Mitigation Measure
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorporate
surface-water diversion and collection mea-
sures as appropriate (see EPA 1982, Sections 3.3
and 3.4); decreased flow may be unavoidable
fugitive-dust control (see Addendum 1)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
3.13
-------
TABLE 3.1f. Surface Controls: Surface Sealing—Bituminous Concrete Covering
Affected Area
Effect
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
bituminous concrete construction will result
in emission of heavy hydrocarbons
Soils/Geology increased runoff as a result of capping can
cause erosion
Mitigation Measure
Biota
fugitive dust from capping can affect nearby
biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorporate
surface-water diversion and collection mea-
sures as appropriate (see EPA 1982, Sections 3.3
and 3.4); decreased flow may be unavoidable
fugitive-dust control (see Addendum 1)
none; unavoidable, but brief effect of this
technology
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
3.14
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TABLE 3.1g. Surface Controls: Surface Sealing—Bituminous Membrane Covering
Affected Area
Effect
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
bituminous concrete construction will result
in emission of heavy hydrocarbons
Soils/Geology increased runoff as a result of capping can
cause erosion
Biota
fugitive dust from capping can affect nearby
biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
Mitigation Measure
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorporate
surface-water diversion and collection mea-
sures as appropriate (see EPA 1982, Sections 3.3
and 3.4); decreased flow may be unavoidable
fugitive-dust control (see Addendum 1)
none; unavoidable, but brief effect of this
technology
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
3.15
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TABLE 3.1h. Surface Controls: Surface Sealing—Sprayed Sulfur/Polyurethane Membranes
Affected Area
Effect
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
Soils/Geology increased runoff as a result of capping can
cause erosion
Mitigation Measure
Biota
fugitive dust from capping can affect nearby
biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorporate
surface-water diversion and collection mea-
sures as appropriate (see EPA 1982, Sections 3.3
and 3.4); decreased flow may be unavoidable
fugitive-dust control (see Addendum 1)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
3.16
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TABLE 3.1L Surface Controls: Surface Sealing—Poly (Vinyl Chloride, Ethylene, etc.) Covers
Affected Area
Effect
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
Soils/Geology increased runoff as a result of capping can
cause erosion
Biota
fugitive dust from capping can affect nearby
biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
Mitigation Measure
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorpo-
rate surface-water diversion and collection
measures as appropriate (see EPA 1982, Sec-
tions 3.3 and 3.4); decreased flow may be
unavoidable
fugitive-dust control (see Addendum 1)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
3.17
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TABLE 3.1j. Surface Controls: Surface Sealing—Industrial Residues
Affected Area
Effect
Ground-Water if run-on and runoff waters are not disposed of
Quality properly, lateral infiltration can result in
ground-water contamination
fly ash, bottom ash and slag, furnace slag, and
incinerator residue contain heavy metals that
leach and contaminate ground water
nontoxic industrial sludges and composted
sewage sludge may contain significant quanti-
ties of objectionable matter that can leach and
contaminate ground water
leachates from industrial residue can change
groundwater chemistry and mobilize toxics
Surface-Water increased runoff as a result of capping can
Quality cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
Soils/Geology increased runoff as a result of capping can
cause erosion
Mitigation Measure
Biota
fugitive dust from capping can affect nearby
biota
erosion can remove terrestrial habitat
sediment from erosion and increased runoff
can affect aquatic biota
understand ground-water hydrology in suffi-
cient detail to know fate of diverted waters
select and test candidate capping material
carefully
select and test candidate capping material
carefully
select and test candidate capping material
carefully
incorporate surface-water diversion and col-
lection measures with revegetation as approp-
riate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorpo-
rate surface-water diversion and collection
measures as appropriate (see EPA 1982, Sec-
tions 3.3 and 3.4); decreased flow may be
unavoidable
fugitive-dust control (see Addendum 1)
incorporate surface-water diversion and col-
lection measures with revegetation as approp-
riate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see soils/geology above
see soils/geology above
3.18
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TABLE 3.2a. Surface Controls: Grading—Slope Grading
Affected Area
Effect
Mitigation Measure
Surface-Water runoff from soils disturbed during grading
Quality activities can carry sediment to receiving
waters
if soil is contaminated, runoff can carry con-
taminated sediment to receiving waters
increased runoff as a result of grading can
cause erosion and carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
if surface soil is contaminated, grading opera-
tions may raise contaminated fugitive dusts
Soils/Geology increased runoff as a result of grading can
cause erosion
Biota
Public Health
or Safety
fugitive dust (contaminated or uncontami-
nated) from grading can affect nearby biota
sediment (contaminated or uncontaminated)
from grading or changed flow patterns can
affect aquatic biota
changed flow in receiving waters can affect
resident aquatic biota
contaminated fugitive dust or contaminated
sediment from grading activities can carry
hazardous material off site
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
if increased flow will be a problem, incorpo-
rate surface-water diversion and collection
measures as appropriate (see EPA 1982, Sec-
tions 3.3 and 3.4); decreased flow may be
unavoidable
fugitive-dust control (see Addendum 1)
control of contaminated fugitive dust (see
Addendum 1)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
prevention is key (see air quality above);
remediation difficult
see surface-water quality above
see surface-water quantity above
see air quality and surface-water quality above
3.19
-------
TABLE 3.2b. Surface Controls: Grading—Topsoil Hauling
Affected Area Effect Mitigation Measure
Air Quality hauling activities will result in release of fugi- none; unavoidable; schedule hauling so that
live dusts along route effect is minimized
hauling activity will result in noise along the none; unavoidable; schedule hauling so that
route effect is minimized
Public Health hauling activities increase traffic safety hazard none; unavoidable; route and schedule haul-
or Safety along truck routes ing to minimize effect
3.20
-------
TABLE 3.2c. Surface Controls: Grading—Scarification or Contouring
Affected Area Effect Mitigation Measure
Surface-Water runoff from soils disturbed during contouring incorporate revegetation as appropriate (see
Quality activities can carry sediment to receiving EPA 1982, Section 3.3)
waters
Air Quality contouring activities can result in release of fugitive-dust control (see Addendum 1)
fugitive dusts
Biota
fugitive dust from contouring activities can affect prevention is key (see air quality above);
nearby biota remediation difficult
sediment carried to receiving waters can affect see surface-water quality above
resident biota
3.21
-------
TABLE 3.3a. Surface Controls: Revegetation
Affected Area
Effect
Mitigation Measure
Ground-Water fertilizers and/or other agricultural chemicals
Quality can infiltrate and contaminate ground water
root system can breach capping and lead to
ground-water contamination
Surface-Water root system can breach capping and lead to
Quality surface-water contamination
facilities and or other agricultural chemicals
can run off and contaminate ground water
Soils/Geology root system can breach capping and lead to
soil contamination
Biota
Public Health
or Safety
root system can breach capping and vegeta-
tion can take up contaminants, introducing
toxics into food chain
noxious or poisonous plant species may be
inadvertently introduced
root system can breach capping leading to
public exposure
if soil is contaminated or roots penetrate
waste, plants can take up toxics and expose
public via food chain
careful selection and judicious application of
chemicals
select shallow-rooted species; apply thin herb-
icide layer between cap and surface
see ground-water quality above
careful selection and judicious application of
chemicals
see ground-water quality above
see ground-water quality above
use native communities, if possible; other-
wise, specify seed content and place of origin
see ground-water quality above
establish and enforce policy of not using
vegetative cover for food for humans or
livestock
3.22
-------
TABLE 3.4a. Surface Controls: Surface-Water Diversion and Collection—Dikes and Berms
Affected Area
Effect
Ground-Water dikes and berms, being upgradient of the site,
Quality could induce recharge through the waste and
contaminate ground water
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow i
Movement receiving waters
Mitigation Measure
in
Air Quality construction activities can result in release of
fugitive dusts
Biota fugitive dust or sediment resulting from con-
struction can affect nearby biota
develop a clear understanding of area hydrol-
ogy and implications of technology before
deciding to use
incorporate sedimentation basins or ponds
early in remediation process (see EPA 1982,
Section 3.4)
if increased flow will be a problem, incorpo-
rate seepage basin or ditch early in remedia-
tion process (see EPA 1982, Section 3.4)
fugitive-dust control (see Addendum 1)
prevention is key (see air quality and surface-
water quality above); remediation difficult
3.23
-------
TABLE 3.4b. Surface Controls: Surface-Water Diversion and Collection—Ditches, Diversions,
and Waterways
Affected Area
Effect
Ground-Water ditches, diversions, and waterways skirt the
Quality site and could cause recharge through the
waste and contaminate ground water
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
Biota fugitive dust or sediment resulting from con-
struction can affect nearby biota
Public Health low spots can hold water and establish a breed-
Mitigation Measure
or Safety
ing ground for insects
develop a clear understanding of area hydrol-
ogy and implications of technology before
deciding to use
incorporate sedimentation basins or ponds
early in the remediation process (see EPA 1982,
Section 3.4)
if increased flow will be a problem, incorpo-
rate seepage basins early in the remediation
process (see EPA 1982, Section 3.4)
fugitive-dust control (see Addendum 1)
prevention is key (see air quality and surface-
water quality above); remediation difficult
establish and enforce an inspection and main-
tenance program
3.24
-------
TABLE 3.4c. Surface Controls: Surface-Water Diversion and Collection—Terraces and Benches
Affected Area
Effect
Ground-Water upgradient terraces or benches could induce
Quality recharge through the waste and contaminate
ground water
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
Biota fugitive dust or sediment resulting from con-
struction can affect nearby biota
Mitigation Measure
develop a clear understanding of area hydrol-
ogy and implications of technology before
deciding to use
incorporate sedimentation basins or ponds
early in the remediation process (see EPA 1982,
Section 3.4)
if increased flow will be a problem, incorpo-
rate seepage basin or ditch early in the reme-
diation process (see EPA 1982, Section 3.4)
fugitive-dust control (see Addendum 1)
prevention is key (see air quality and surface-
water quality above); remediation difficult
3.25
-------
TABLE 3.4d. Surface Controls: Surface-Water Diversion and Collection—Chutes and Downspouts
Affected Area
Effect
Mitigation Measure
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water changed runoff patterns can change flow in
Movement receiving waters
Air Quality construction activities can result in release of
fugitive dusts
Biota fugitive dust or sediment resulting from con-
struction can affect nearby biota
incorporate sedimentation basins or ponds
early in the remediation process (see EPA 1982,
Section 3.4)
if increased flow will be a problem, incorpo-
rate seepage basin or ditch early in the reme-
diation process (see EPA 1982, Section 3.4)
fugitive-dust control (see Addendum 1)
prevention is key (see air quality and surface-
water quality above); remediation difficult
3.26
-------
TABLE 3.4e. Surface Controls: Surface-Water Diversion and Collection—Levees
Affected Area
Effect
Mitigation Measure
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water levees to prevent on-site flooding will tend to
Movement increase off-site flooding directly upstream
Air Quality construction activities can result in release of
fugitive dusts
Biota fugitive dust or sediment resulting from con-
struction can affect nearby biota
Public Health runoff collecting on the uphill side of the
or Safety levee can provide a breeding area for noxious
insects
temporary, but may be unavoidable; tempor-
ary sedimentation basin or pond might be
used (see EPA 1982, Section 3.4)
none; unavoidable aspect of use of this
technology
fugitive-dust control (see Addendum 1)
prevention is key (see air quality and surface-
water quality above); remediation difficult
include upslope collection area in design, and
pump regularly
3.27
-------
TABLE 3.4f. Surface Controls: Surface-Water Diversion and Collection—Seepage Basins and Ditches
Effect
Affected Area
Surface-Water runoff from soils disturbed during construc-
tion activities can carry sediment to receiving
waters
Quality
Air Quality
construction activities can result in release of
fugitive dusts
Biota fugitive dust or sediment resulting from con-
struction can affect nearby biota
seepage basins and ditches may trap small
wildlife
Public Health seepage basins and ditches that have been in
or Safety use for some time generally hold standing
water and, therefore, can be breeding grounds
for noxious insects
deep seepage basins and ditches may be a
public hazard if people can fall in them
Mitigation Measure
incorporate sedimentation basins or ponds
early in the remediation process (see EPA 1982,
Section 3.4)
fugitive-dust control (see Addendum 1)
prevention is key (see air quality and surface-
water quality above); remediation difficult
walls should not be steep enough to trap
wildlife
establish and enforce schedule for inspection
and rehabilitation
establish security to control public access
3.28
-------
4.0 GROUND-WATER CONTROLS
Ground-water controls are implemented to prevent contaminated ground water from migrating away
from the uncontrolled hazardous-waste site or to divert ground water to prevent contact with waste
materials.
4.1 IMPERMEABLE BARRIERS
Impermeable barriers are used to divert ground-water flow away from an uncontrolled hazardous-
waste site or to contain contaminated ground water at the site. Three impermeable-barrier methods
used to control ground-water movement are addressed in EPA 1982: slurry walls, grout curtains, and
sheet-piling cutoff walls. The potential effects associated with the use of impermeable barriers are
summarized in Table 4.1 and described in the good engineering practice tables, Tables 4.1a-c, at the
end of this section.
Certain potential adverse environmental effects are common to all of these impermeable barrier
methods for controlling ground water. Impermeable barriers will, by design, divert ground-water flow.
Diverting the flow will increase ground-water heads in some areas bordering the site and decrease
heads in others. If these increased heads intercept the surface or manmade structures, significant
nuisance effects may occur. For instance, if the local water table intercepts the surface, seeps and
springs will be formed. Aside from the direct nuisance caused by seeps and springs, there may be an
effect on the utility of the soil for agricultural use where they occur. If the head is increased such that
the local water table intercepts basements or sewer lines, basement flooding, sewer-line backup, or
overload of the sewer system is possible. If the change in head creates new discharge to local surface
waters or reduced discharge to other surface waters, small streams and the biota inhabiting these
streams and the riparian areas may be adversely affected. These adverse effects can best be remedied
by studying in detail how the planned remedial action will affect the local water table before taking
TABLE 4.1. Effects of Ground-Water Controls: Impermeable Barriers
All Methods
Slurry Walls
Grout Curtains
Sheet-Piling
Cutoff Walls
Ground-Water
Movement/
Surf ace-Water
Movement/ Air
Soils/
Public
Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
OHPR
OHPR
ON PR
ONPR
9NPR
>NSI
• NSR
OHPR
ONPR ONSR —
— OHPI OHPI
»HPR —
• = Highly Probable d = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
4.1
-------
action. If impermeable barriers are deemed to be absolutely necessary but the change in the water
table causes negative effects off site by intercepting manmade structures or the surface, then addi-
tional off-site ground-water controls such as impermeable barriers or drains, may be required to
prevent these negative effects. All studies of the effect of the impermeable barriers on the local water
table should consider seasonal variations and include future human activities that may affect the local
water table (e.g., irrigation or off-site residential development).
Because each of the impermeable barrier methods involves construction activities, with consequent
local soil disruption, fugitive dust could be released either containing or not containing hazardous
material. These fugitive dusts may affect nearby biotic communities. In addition, runoff from the
disturbed area can contribute to sediment loading in local surface waters with consequent effect on
biota inhabiting the waters. Contaminated fugitive dust or sediments transported off site can present a
hazard to public health. Fugitive dust emitted during construction-related activities can be reduced by
water spraying or other measures (see Addendum 1). Surface-water diversion and collection measures
together with revegetation (see Sections 3.3 and 3.4 of EPA 1982) can prevent surface-water quality from
being degraded as a result of these construction activities.
The use of impermeable barriers to control ground water may interact with measures taken to control
gaseous releases and adversely affect the ventilation of the hazardous-waste site (see Sections 6 of EPA
1982 and of this document). If ventilation is affected, noxious or hazardous vapors could be released
with potential exposure to humans and biota. Remedying this potential effect simply involves consider-
ing potential interactions between measures taken.
A possible effect specific to slurry wall construction is that, during excavation, an aquitard may be
breached or damaged, connecting a contaminated aquifer to an uncontaminated aquifer. If this were
to occur, some remedy of the contamination of the new aquifer would be required. Damage to the
aquitards should be carefully avoided through detailed study of the hydrology and devising and
enforcing excavation procedures before beginning operation.
During the construction of grout curtains, numerous holes are drilled to bedrock or to a significant
aquitard encircling the uncontrolled hazardous-waste site. Each of the holes could potentially pene-
trate an aquitard and connect an uncontaminated aquifer to a contaminated aquifer. Again, the best
remedy for this potential effect is to prevent its occurrence by carefully logging the material through
which the hole is being drilled. If such penetration does occur, the hole should be sealed with a
physically strong and impermeable material and monitored.
Additionally, some of the grouts that are described for use for grout curtains (EPA 1982) are themselves
toxicand/or noxious (for instance, the lignochromium and acrylamide grouts). Use of lignochromium
grouts (which are based on hexavalent chromium) could potentially contaminate ground water or, if
spilled on site, contaminate the soils. Soil contamination from spills can be remedied by cleanup after
the grouting operation. Acrylamide has been recognized as a neurotoxin and since 1979 has not been
marketed for grouting purposes in the United States (Shafer et al. 1984); the most significant hazard in
the use of acrylamide grouts was to the worker because the material polymerizes quickly after contact
with the soil.
The use of sheet-piling cutoff walls requires a pile driver to insert the sheet piling. Inevitably, the pile
driver creates a noise nuisance factor. Although irremediable, this effect is short term and can be
mitigated in part by operating only during midday hours.
4.2
-------
4.2 PERMEABLE TREATMENT BEDS
Permeable treatment beds treat ground water in situ by intercepting ground-water flow with material
that can remove contaminants. Such material could be limestone, activated carbon, zeolites, locally
obtained glauconitic green sands, or synthetic ion-exchange resins. After the contaminated ground-
water plume has been successfully treated or the treatment bed is exhausted, the treatment bed would
have to be removed and disposed of as contaminated material. The potential effects associated with the
use of permeable treatment beds are summarized in Table 4.2 and described in the good engineering
practice table, Table 4.2a, at the end of this section.
The treatment material, after being removed, could potentially contaminate ground waters at the
disposal site. The contaminants can remobilize if water chemistry at the new site differs from that at the
originating area. Therefore, the treatment medium must be disposed of as a hazardous material in a
Resource Conservation Recovery Act (RCRA)-approved site.
Permeable treatment beds are constructed by excavation to below the water table. If the ground water
is contaminated where the bed is being constructed, the material through which the ground water
flows (i.e., the material being excavated) must be presumed to be contaminated. If the contaminated
soils are not disposed of promptly, these may dry and form a source of contaminated fugitive dust,
thereby transporting the contaminant off site where biota and human health and safety may be
affected. Soils also could be contaminated off site by these fugitive dusts. To prevent contamination off
site, the contaminated soils should be disposed of properly before they can dry ?nd become sources of
fugitive dusts.
Also, these construction activities have the potential for releasing fugitive dusts from surface activities;
construction-related emissions of uncontaminated fugitive dusts can be minimized by keeping the
disturbed soils damp by water spraying and by other measures (see Addendum 1).
Construction-related activities can also cause increased sediment loading to nearby surface waters by
disturbing surface cover. In addition, if the contaminated soils are not disposed of properly and
promptly, the sediment carried to surface water may be contaminated with the hazardous material.
These potential effects could be mitigated by proper handling and prompt disposal of the contami-
nated soils and treating the runoff water from these soils as contaminated. Surface-water diversion and
collection measures together with revegetation (see EPA 1982) can prevent uncontaminated sediments
from increasing sediment loading to nearby surface waters.
TABLE 4.2. Effects of Ground-Water Controls: Permeable Treatment Beds
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
3HPR
N
S
R
NB:
0>HSR
3NSR
3 HSR
= Highly Probable * = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
OHPR 3HPR »HPR
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
= Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
4.3
-------
4.3 GROUND-WATER PUMPING
Ground-water pumping is effected to accomplish three possible goals: 1) to lower the water table
locally and prevent ground water from contacting the waste, 2) to contain a contaminated plume, or
3) to extract contaminated ground water for subsequent treatment. The potential effects associated
with the use of impermeable barriers are summarized in Table4.3 and described in the good engineer-
ing practice table, Table 4.3a, at the end of this section.
Pumping ground water to lower the water table or to contain a contaminant plume involves handling
only uncontaminated water and drilling through uncontaminated media. In this case, potential nega-
tive effects are the long-term commitment of energy for pumping and, if the pumped water is
discharged to surface waters, the effects of increased flows resulting from the discharge on surface-
water movement and quantity and on the biota inhabiting those surface waters. An alternative to
surface-water discharge of the pumped water is to return the water to the aquifer, either through
injection wells or percolation basins. This approach has the additional advantage that it may (although
not necessarily will) contribute to the efficiency of the plume management or water-table manage-
ment if designed accordingly.
If the ground water is pumped to remove contaminated ground water for subsequent treatment, the
construction of the well probably involves drilling through and into contaminated media. (The
negative effects of ground-water treatment options are discussed in Appendix B.) If the drill cuttings
are not handled as contaminated material and are allowed to lie where they fall, these can contaminate
the soil, degrade air quality as contaminated fugitive dust, and degrade surface-water quality as
contaminated suspended sediment. These contaminants can, in turn, negatively affect local biota and
human health and safety. These effects can be prevented by handling the drill cuttings and any material
removed from the well as hazardous material. Proper development of the capture well will probably
require the removal of significant quantities of sediment-laden water from the wells. Since well
completion may very possibly occur before completion of the water-treatment facility, the water and
sediment will have to be stored and handled as hazardous material.
After treatment, the treated ground water must be disposed of. The negative effects of disposing of
contaminated water from pumping will depend on the method of disposal. If it is disposed of to surface
TABLE 4.3. Effects of Ground-Water Controls: Ground-Water Pumping
Ground-Water Surface-Water
Movement/ Movement/ Air
Quality Quantity Quality Quantity Quality
»HPR
ONSR
ONPR
N
S
R
NB:
= Highly Probable 3 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
Soils/
Geology Biota
Public
Health/ Resource
Safety Commitments
• NSR
»HPR
• NSI
<»HPR »HPR 3HPR • NPI
— ONPR —
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
4.4
-------
waters, it could affect surface-water movement and quantity and potentially affect the surface-water
biota because of increased flows. The remedy for these potential negative effects is to reinject the water
through wells or percolation basins.
Another potential negative effect of ground-water pumping is the noise of drilling during construc-
tion. This effect, although irremediable, is short term and only lasts during the process of construction.
The noise-related environmental insult can be remedied in part by confining drilling to normal
working hours.
4.4 INTERCEPTOR TRENCHES
See Section 5.2: Drainage Ditches and Table 4.4.
TABLE 4.4. Ground-Water Controls: Interceptor Trenches
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
SEE SECTION 5.2; DRAINAGE DITCHES
• = Highly Probable 9 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
4.5 BIORECLAMATION
Bioreclamation involves the in situ destruction of ground-water contaminants by exotic biota. In this
process, microorganisms are introduced into the ground water together with nutrients, and the
ground water is aerated. The potential effects associated with the use of bioreclamation are summar-
ized in Table 4.5 and described in the good engineering practice table, Table 4.5a, at the end of this
section.
The construction of the well involves drilling through and into contaminated media. If the drill cuttings
are not handled as contaminated material and are allowed to lie where they fall, these can contaminate
the soil, degrade air quality as contaminated fugitive dust, and degrade surface-water quality as
contaminated suspended sediment. These contaminants can, in turn, negatively affect local biota and
human health and safety. These effects can be prevented by handling the drill cuttings and any material
removed from the well as hazardous material. Proper development of the well will probably require
removal of significant quantities of sediment-laden water from the wells. Since well completion may
very possibly occur before completion of a water treatment facility (if any is to be constructed) the
water and sediment will have to be stored or disposed of as hazardous material.
Another potential negative effect of bioreclamation is the noise of drilling during well construction.
This effect, although irremediable, is short term and only lasts during the process of construction. The
noise-related environmental insult can be remedied, in part, by confining drilling to normal working
hours.
4.5
-------
TABLE 4.5. Ground-Water Controls: Bioreclamation
Ground-Water
Quality
Movement/
Quantity
ONPR
• NPR
Surface-Water
Quality
OHPR
Movement/
Quantity
N
S
R
NB:
= Highly Probable O = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
Air
Quality
OHPR
• NSR
• NSI
Soils/
Geology
Biota
Public
Health/ Resource
Safety Commitments
OHPR (1HPR OHPR
— ONPR —
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
Other negative effects associated with bioreclamation include further ground-water contamination
because nutrients can migrate away from the site and into drinking waters. Finally, the microorgan-
isms could potentially be released outside of the site area. Although this effect may be more serious in
its perception by the public ("you're putting bugs into my drinking water") than real, it must still be
considered.
4.6
-------
TABLE 4.1a. Ground-Water Controls: Impermeable Barriers—Slurry Walls
Affected Area
Effect
Ground-Water excavation may breach aquitard, thereby con-
Quality laminating an additional aquifer
Ground-Water increased heads may intercept land surface
Movement resulting in seeps or springs
increased heads may intercept manmade
structures resulting in flooding or sewer
overload
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water altered ground-water flow may affect water
Movement transfer to surface waters and change stream
flow
Air Quality construction activities can result in release of
fugitive dusts
excavation to aquitard can bring contaminated
soils to surface where these can become con-
taminated fugitive dusts
thi» measure can interfere with ventilation
measures (if used) resulting in airborne vapor
release
Soils/Geology surface seeps or springs (see ground-water
movement above) may reduce land utility
Biota changed surface-water flow (see surface-water
movement above) may affect resident biota
fugitive dust (contaminated or uncontami-
nated) from excavation can affect nearby
biota
sediment (contaminated or uncontaminated)
from excavation can affect aquatic biota
Public Health contaminated fugitive dust or contaminated
or Safety sediment from excavation activities can carry
hazardous material off the site and expose
public
Mitigation Measure
know hydrology in detail; devise and enforce
procedures for excavation
model off-site changes in water table, includ-
ing potential land-use changes; install off-site
ground-water controls if needed
model off-site changes in watertable, including
potential land-use changes; install off-site
ground-water controls if needed
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
model off-site changes in water table, includ-
ing potential land-use changes; install off-site
ground-water controls if needed
control of contaminated fugitive dust (see
Addendum 1)
control of contaminated fugitive dust (see
Addendum 1)
consider possible interactions between
measures
see ground-water movement above
see surface-water movement above
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
4.7
-------
TABLE 4.1b. Ground-Water Controls: Impermeable Barriers—Grout Curtains
Affected Area
Effect
Mitigation Measure
Ground-Water drilling may breach aquitard, thereby contam-
Quality inating additional aquifer
lignochromium grouts may contaminate
ground water
Ground-Water increased heads may intercept land surface
Movement resulting in seeps or springs
increased heads may intercept manmade
structures resulting in flooding or sewer
overload
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water altered ground-water flow may affect water
Movement transfer to surface waters and change stream
flow
Air Quality construction activities can result in release of
fugitive dusts
drilling to aquitard can bring contaminated
soils to surface where these can become con-
taminated fugitive dusts
this measure can interfere with ventilation
measures (if ventilation is used) resulting in
airborne vapor release
Soils/Geology surface seeps or springs (see above) may
reduce land utility
spills of toxic grouts may contaminate surface
soils
Biota
Public Health
or Safety
changed surface-water flow above may affect
resident biota
fugitive dust (contaminated or uncontami-
nated) from drilling can affect nearby biota
sediment (contaminated or uncontaminated)
from drilling operation can affect aquatic
biota
contaminated fugitive dust or contaminated
sediment from drilling activities can carry
hazardous material off the site
know hydrology in detail; devise and enforce
procedures for drilling; if breach of aquitard
occurs, seal entire drill hole
be certain that grouts are chemically suitable
for on-site conditions
model off-site changes in water table, includ-
ing potential land-use changes; install off-site
ground-water controls if needed
model off-site changes in water table, includ-
ing potential land-use changes; install off-site
ground-water controls if needed
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
model off-site changes in water table, includ-
ing potential land-use changes; install off-site
ground-water controls if needed
fugitive-dust control (see Addendum 1)
handle drill cuttings as hazardous matter
consider possible interactions between
measures
see ground-water movement above
plan for spills by using dedicated material
handling area; plan to clean up area
(see surface-water movement above)
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
4.8
-------
TABLE 4.1c. Ground-Water Controls: Impermeable Barriers—Sheet-Piling Cutoff Walls
Affected Area
Effect
Mitigation Measure
Ground-Water increased heads may intercept land surface
Movement resulting in seeps or springs
increased heads may intercept manmade
structures resulting in flooding or sewer
overload
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water altered ground-water flow may affect water
Movement transfer to surface waters and change stream
flow
Air Quality construction activities can result in release of
fugitive dusts
this measure can interfere with ventilation
measures (if used) resulting in airborne vapor
release
pile-driver installation of sheet-piling cutoff
walls will create noise
Soils/Geology surface seeps or springs (see ground-water
movement above) may reduce land utility
Biota changed surface-water flow (see above) may
affect resident biota
fugitive dust (contaminated or uncontami-
nated) from construction activities can affect
nearby biota
sediment (contaminated or uncontaminated)
from construction activities can affect aquatic
biota
Public Health contaminated fugitive dust or contaminated
or Safety sediment from construction activities can carry
hazardous material off the site
model off-site changes in water table, potential
land-use changes; install off-site ground-water
controls if needed
model off-site changes in water table, including
potential land-use changes; install off-site
ground-water controls if needed
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
model off-site changes in water table, includ-
ing potential land-use changes; install off-site
ground-water controls if needed
fugitive-dust control (see Addendum 1)
consider possible interactions between
measures
schedule pile-driver operating hours to reduce
public nuisance
see ground-water movement above
see surface-water movement above
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
4.9
-------
TABLE 4.2a. Ground-Water Controls: Permeable Treatment Beds
Affected Area Effect
Ground-Water treatment material may contaminate ground
Quality waters at site of disposal
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
excavation into aquifer can bring contami-
nated soils to surface where these can be car-
ried to receiving waters by overland flow
Air Quality construction activities can result in release of
fugitive dusts
excavation into aquifer can bring contami-
nated soils to surface where these can become
contaminated fugitive dusts
Soils/Geology excavation into aquifer can bring contami-
nated soils to surface where these can
contaminate surface soils
Mitigation Measure
Biota
Public Health
or Safety
fugitive dust (contaminated or uncontami-
nated) from excavation can affect nearby biota
sediment (contaminated or uncontaminated)
from excavation can affect aquatic biota
contaminated fugitive dust or contaminated
sediment from excavation activities can carry
hazardous material off the site
handle spent treatment-bed material as con-
taminated matter; dispose of in a RCRA-
approved site
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
handle and dispose of excavated material as
contaminated matter
fugitive-dust control (see Addendum 1)
handle and dispose of excavated material as
contaminated matter
see air quality above
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
4-10
-------
TABLE 4.3a. Ground-Water Controls: Ground-Water Pumping
Affected Area
Effect
Mitigation Measure
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
runoff of soils contaminated by drill cuttings
or development water may contaminate sur-
face water
Surface-Water discharge of pumped water to receiving waters
Movement will increase surface-water flows
Air Quality construction activities can result in release of
fugitive dusts
soils contaminated by drill cuttings or devel-
opment water may form contaminated fugi-
tive dusts
drilling will produce noise
Soils/Geology drill cuttings may contaminate soil
water pumped from well to develop well may
contaminate soil
Biota changed surface-water flow (see above) may
affect resident biota
fugitive dust (contaminated or uncontami-
nated) from activity can affect nearby biota
sediment (contaminated or uncontaminated)
from activity can affect aquatic biota
Public Health contaminated fugitive dust or contaminated
or Safety sediment from drilling or well development
activities can carry hazardous material off the
site
Resource use of ground-water pumping to isolate waste
Commitments involves commitment of energy and other
resources for pumping for an indefinite period
use of pump-and-treat option involves com-
mitment of energy and other resources for
period of treatment
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
see soils/geology below
if adverse effects can result from increased
flow, use reinjection wells or use percolation
basins
fugitive-dust control (see Addendum 1)
see soils/geology
none; unavoidable but temporary, reduce
effect of noise by scheduling drilling
handle and dispose of drill cuttings as hazard-
ous matter
handle development waters as hazardous mat-
ter and store for treatment
see surface-water movement above
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
none; unavoidable effect of this technology
none; unavoidable effect of this technology
4.11
-------
TABLE 4.5a. Ground-Water Controls: Bioreclamation
Affected Area
Effect
Ground-Water nutrients introduced to assist microbiota may
Quality contaminate nearby drinking waters
microorganisms introduced to degrade toxic
matter may be released off site
Surface-Water runoff from soils disturbed during drilling
Quality activities can carry sediment to receiving
waters
runoff of soils contaminated by drill cuttings
or development water may contaminate sur-
face water
Air Quality construction activities can result in release of
fugitive dusts
soils contaminated by drill cuttings or devel-
opment water may form contaminated fugi-
tive dusts
drilling will produce noise
Soils/Geology drill cuttings may contaminate soil
water pumped from well to develop well may
contaminate soil
Biota fugitive dust (contaminated or uncontami-
nated) from activity can affect nearby biota
sediment (contaminated or uncontaminated)
from activity can affect aquatic biota
Public Health contaminated fugitive dust or contaminated
or Safety sediment from drilling or well development
activities can carry hazardous material off the
site
Mitigation Measure
mitigation difficult; careful study of ground-
water flow, monitoring of treated flow, and
planning are key
primarily a public perception issue; mitigable
by education
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
see soils/geology below
fugitive-dust control (see Addendum 1)
see soils/geology below
none; unavoidable, but temporary; reduce
effect of noise by scheduling drilling
handle and dispose of drill cuttings as hazard-
ous matter
handle development waters as hazardous
matter and store for treatment
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
4.12
-------
5.0 LEACHATE COLLECTION AND TREATMENT
Leachate is defined as the contaminated liquid discharged from a waste disposal site to either surface or
subsurface receptors. Leachate collection systems consist of a series of drains that intercept the
leachate and channel it to an ultimate treatment point. The drains may consist of open ditches or
trenches or pipe or tile drain fields. To a limited extent, liners may be used to assist in leachate
collection.
5.1 SUBSURFACE DRAINS
Subsurface drains consist of underground gravel-filled trenches lined with tile or perforated pipe.
These drains intercept leachate (or infiltrating water destined to become leachate) and transport this
water to a treatment point (or disposal point, as appropriate). The potential effects of the use of
subsurface drains are summarized in Table 5.1 and described in the good engineering practice table,
Table 5.1a, at the end of this section.
The most serious potential adverse effect associated with the use of subsurface drains is that this
method is only effective in saturated soils because the drains will only collect leachate below the local
water table (this restriction does include a perched water table). Thus, if the water table changes
significantly with season, leachate may move by unsaturated-zone transport and escape a collection
system consisting of subsurface drains, or infiltrating water may escape the drains and become
leachate, leading to contamination of ground water. Therefore, re lying on subsurface drains may lead
to a false sense of security because the drains may be dry, while, in fact, the leachate is going around the
drains. A possible remedy for this effect is to create a perched aquifer by engineering an under-landfill
liner (see Section 5.3 of this document and of EPA 1982). However, this remedy is fraught with potential
hazard and success is not certain.
Other potential adverse effects from subsurface drains are related to construction activities that disturb
the surface. Fugitive dusts can degrade air quality, but can be controlled by water spraying and other
methods (see Addendum 1). Runoff from disturbed soils can affect surface-water quality and the biota
inhabiting that surface water. These effects may be prevented through the use of surface-water
diversion and collection methods together with revegetation (see Sections 3.3 and 3.4 of EPA 1982).
TABLE 5.1. Leachate Collection and Treatment: Subsurface Drains
Ground-Water
Quality
Movement/
Quantity
Surface-Water
Quality
Movement/
Quantity
3NSR
3HPR
Air
Quality
• NSR
9HPR
Soils/
Geology
9HPR
Biota
ONPR
3HPR
Public
Health/ Resource
Safety Commitments
3NPR —
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
5.1
-------
If the subsurface drain is intended to collect leachate, excavation very probably will proceed into a
contaminated zone. If the excavated soils are not handled accordingly, fugitive dusts and surface
runoff from these contaminated soils can be a hazard both to neighboring biota and man. These
potential adverse effects can be remedied by treating the excavated material as hazardous and
disposing of it accordingly.
5.2 DRAINAGE DITCHES
Drainage ditches can be used for two purposes in remedial action. First, they can collect or divert
ground water as part of a ground-water-control strategy (see Section 4.4 of EPA 1982). Second, drainage
ditches can be used as part of a leachate collection system for subsequent treatment. The potential
effects of the use of drainage ditches are summarized in Table 5.2 and described in the good
engineering practice table, Table 5.2a, at the end of this section.
Regardless of the purpose, the construction of the drainage ditches can cause adverse effects on
surface-water quality, air quality, and biota. Sediment carried from the construction site by overland
flow can degrade surface-water quality in receiving streams and can adversely affect biota residing in
those streams. This can be prevented by using surface-water diversion and collection methods
together with revegetation (see Sections 3.3 and 3.4 of EPA 1982) as part of the overall site activity.
Air quality can be degraded as a result of fugitive dust from construction activities. This can be
controlled via the appropriate use of water spraying or other methods (see Addendum 1).
If the trench is being constructed to intercept leachate, it is highly probable that the excavated soil will
be contaminated with the hazardous material. This soil can become airborne or carried to receiving
streams by overland flow unless specific measures are taken. In either case, the contaminants being
transferred off site may present a hazard for man and biota. This effect can be prevented by treating the
contaminated soil as hazardous matter and disposing of it in an appropriate fashion.
TABLE 5.2. Leachate Collection and Treatment: Drainage Ditches
Ground-Water
Movement/
Quality Quantity
Collect & Divert
Ground Water
Collect Leachate
for Treatment
Surface-Water
Quality
9 NSR
3 NSR
3HPR
Movement/
Quantity
9NPR
—
Air
Quality
• NSR
9HPR
• NSR
0>HPR
Soils/
Geology
Biota
Public
Health/ Resource
Safety Commitments
9 NSR 9NPR
9NPR —
9 NSR 3HPR
»HPR ONPR
dNPR —
• = Highly Probable 3 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
5.2
-------
Drainage ditches are generally from six to twelve feet deep and are intended to hold standing water or
leachate (EPA 1982). A six-to-twelve-foot-deep trench filled with water forms a potential trap for man
and terrestrial biota. The hazard to human safety can be remedied by additional security, fencing, and
other measures. By covering the drain, the hazard to terrestrial biota can be mitigated as well.
The standing water in the trenches also forms a potential breeding ground for mosquitoes and other
noxious insects. As such, these ditches could be judged to be a public nuisance. Also if a riparian zone is
allowed to develop around the standing water, the trench can tend to become an attractive environ-
ment for birds and mammals. If the standing water or vegetation contains biota that are food for game
birds, a pathway to the human food chain may be created. The ditches can be prevented from
becoming a breeding ground by covering them or maintaining an oil film on the standing water.
Vegetative growth can be prevented through herbicide application. The use of any additive must be
considered in regard to the effect of that additive on the overall treatment package.
If the drainage trench is being used specifically to collect and divert ground-water flow, the quantity
and movement of the receiving water into which this ground water is discharged may be affected,
along with the biota that inhabit these receiving waters. This effect can be prevented by using
percolation basins or injection wells as part of the ground-water-control strategy.
5.3 LINERS
As noted in Section 5.1, drains are only effective when operating below the local water table. The use of
an under-the-waste liner can create a perched water table of leachate and, thereby, make such
subsurface drains effective. The potential effects of the use of liners are summarized in Table 5.3 and
described in the good engineering practice tables, Tables 5.3a and b, at the end of this section.
EPA (1982) describes two methods for creating under-waste liners. The first, under-waste grouting,
involves drilling through the waste and grouting the soil beneath. The second involves slurrying
bentonite into an existing lagoon; the bentonite would then settle to the bottom and consolidate to
form a liner.
TABLE 5.3. Leachate Collection and Treatment: Liners
Ground-Water
Quality
Under-Waste
Grouting
Bentonite
Slurry
Movement/
Quantity
Surf ace-Water
Quality
3HPR
»NSR
Movement/
Quantity
Air
Quality
Soils/
Geology
Biota
Public
Health/ Resource
Safety Commitments
OHPR OHPR OHPR OHPR
• NSR — — »HPR
ONSR — — —
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
5.3
-------
Implementing under-waste grouting involves drilling through the waste or the use of slant-drilling
techniques. Drilling into waste is recognized to be a hazardous activity. Waste-disposal sites have been
known to contain compressed gases and pyrophoric and explosive materials. A fire or explosion
initiated by the drilling process would release hazardous material that could be a persistent hazard to
human health and safety and biota. This contamination could also cause a persistent degradation of
surface-water quality and contamination of soils in the vicinity.
Drill cuttings also will very likely be contaminated with hazardous matter. If they are left as they lie, they
can evolve into contaminated fugitive dust or contaminated sediments in runoff, thereby degrading air
quality and surface-water quality, respectively. This effect is mitigated by treating the drill cuttings as
hazardous matter and disposing of them accordingly. Slant drilling under the waste is a possible
alternative to drilling through the waste. This option is, however, very expensive and subject to limited
applicability.
Construction-related activities at the site associated with the drilling and grouting will disturb surface
soils and create fugitive dusts. The fugitive dust will degrade air quality; this can be remedied in part by
water spraying and other methods (see Addendum 1).
Disturbing the surface cover also will lead to sediment in runoff. This can be prevented through the use
of surface-water diversion and collection measures together with revegetation (see Sections 3.3 and 3.4
of EPA 1982).
The use of powdered bentonite to form a slurry can result in fugitive dust, which can degrade air
quality. This effect is transitory, lasting only during the period during which the bentonite is being
applied. It may be mitigated by applying the bentonite as a slurry.
5.4 TREATMENT
See Appendix B and Table 5.4.
TABLE 5.4. Leachate Collection and Treatment: Treatment
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
SEE APPENDIX B
• = Highly Probable O = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
5.4
-------
TABLE 5.1a. Leachate Collection and Trea'ment: Subsurface Drains
Affected Area
Effect
Mitigation Measure
Ground-Water if drained region becomes unsaturated, drains
Quality will be ineffective and leachate may escape
collection leading to ground-water
contamination
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
runoff containing excavated matter may carry
contaminated sediments to receiving waters
Air Quality construction activities can result in release of
fugitive dusts
contaminated soil resulting from excavation
can become contaminated fugitive dusts
Soils/Geology excavated matter may contain hazardous
material and may contaminate soils
Biota fugitive dust (contaminated or uncontami-
nated) from excavation can affect nearby biota
sediment (contaminated or uncontaminated)
from excavation can affect aquatic biota
Public Health contaminated fugitive dust or contaminated
or Safety sediment from excavation activities can carry
hazardous material off the site and expose
public
ensure that drained region is saturated
year-round; alternative is to create perched
water table by engineering an under-landfill
liner (see EPA 1982, Section 5.3)
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
see soils/geology below
fugitive-dust control (see Addendum 1)
see soils/geology below
contain excavated material and handle as con-
taminated matter
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
5.5
-------
TABLE 5.2a. Leachate Collection and Treatment: Drainage Ditches
Affected Area
Effect
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
runoff containing excavated matter may carry
contaminated sediments to receiving waters
Surface-Water drainage ditches to collect and divert ground-
Quality water flow may affect flow of surface water in
receiving waters
Air Quality construction activities can result in release of
fugitive dusts
contaminated soil resulting from excavation
can become contaminated fugitive dusts
Soils/Geology excavated matter may contain hazardous
material and may contaminate soils
Biota fugitive dust (contaminated or uncontami-
nated) from excavation can affect nearby biota
sediment (contaminated or uncontaminated)
from excavation can affect aquatic biota
drainage ditch may present hazard to wildlife
which might fall into it
Public Health contaminated fugitive dust or contaminated
or Safety sediment from excavation activities can carry
hazardous material off the site and expose
public
if riparian zone develops, a contaminant
pathway to human food chain may be
established
drainage ditch may present hazard to public
who might fall into it
standing water in drainage ditch can be an
insect breeding area
Mitigation Measure
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
see soils/geology below
if significant, use percolation basins or injec-
tion wells as part of the ground-water control
strategy
fugitive-dust control (see Addendum 1)
see soils/geology below
contain excavated material and handle as con-
taminated matter
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
cover the drainage ditch
see air quality and surface-water quality above
prevent vegetative growth with herbicides
secure area from public
use covers and/or oil film
5.6
-------
TABLE 5.3a. Leachate Collection and Treatment: Liners—Under-Waste Grouting
Affected Area
Effect
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
runoff containing drill cuttings may carry con-
taminated sediments to receiving waters
Air Quality construction activities can result in release of
fugitive dusts
contaminated soil resulting from drill cuttings
can become contaminated fugitive dusts
Soils/Geology drill cuttings may contain hazardous material
and may contaminate soils
Biota
Public Health
or Safety
fugitive dust (contaminated or uncontami-
nated) from activity can affect nearby biota
sediment (contaminated or uncontaminated)
from activity can affect aquatic biota
contaminated fugitive dust or contaminated
sediment from excavation activities can carry
hazardous material off the site and expose
public
drilling can encounter pyrophoric or explo-
sive matter, which could result in a significant
release and public exposure
Mitigation Measure
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
see soils/geology below
fugitive-dust control (see Addendum 1)
see soils/geology below
contain excavated material and handle as con-
taminated matter
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
establish and enforce drilling procedures
5.7
-------
TABLE 5.3b. Leachate Collection and Treatment: Liners—Bentonite Slurry
Affected Area Effect Mitigation Measure
Air Quality handling of dry bentonite powder can result handle bentonite as a slurry
in fugitive dust
5.8
-------
6.0 GAS-MIGRATION CONTROLS
Gas-migration controls are used to control the lateral movement of flammable and volatile toxic gases
and to control emissions to the atmosphere of volatile toxic compounds from an uncontrolled
hazardous-waste site.
6.1 PIPE VENTS
Pipe vents include vertical or lateral perforated pipe installed in and around the landfill. Possible effects
of the use of pipe vents are summarized in Table 6.1 and described in the good engineering practice
table. Table 6.1a, at the end of this section.
Installing vertical pipes in the landfill involves drilling through the waste site. Drilling through
hazardous-waste sites is risky. Methane in the ground can become diluted to explosive limits during
the drilling and installation operations. Thus, explosion and fire are potential adverse effects resulting
from use of this technology. This effect should be addressed when developing drilling plans.
When a pipe vent system is successfully installed, methane and other products of anaerobic decompo-
sition are released to the atmosphere, together with vapors of any of the toxic materials that may be
present. The release of these toxic vapors presents a small but not-insignificant potential health and
safety hazard to humans and biota. The release of the methane and other products of anaerobic
decomposition could create a local degradation in air quality, because anaerobic decomposition
produces gases other than methane, some of which are extremely offensive. The release of these
offensive gases can be prevented only by using gas-collection and -treatment or -recovery measures
(see Sections 6.4, 6.5, and 6.6 of EPA 1982).
Surface soils may be disrupted by construction of the venting system. Loose soils can become fugitive
dusts and contami nate the air locally or can be carried by surface ru noff to receivi ng waters, where they
contribute to the sediment load. Release of uncontaminated soils as fugitive dusts can be prevented by
water spraying or other measures (see Addendum 1). Runoff containing uncontaminated soils can be
prevented using surface-water diversion and collection measures together with revegetation (see
Ground-Water
TABLE 6.1. Effects of Gas-Migration Controls: Pipe Vents
Surface-Water
Movement/
Quality Quantity Quality
OHPR — CJHPR
— — «NSR
Movement/ Air
Quantity Quality
ONPR
»HPR
• NSR
Soils/
Geology Biota
Public
Health/ Resource
Safety Commitments
OHPR OHPR »HPR
>NPI
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
6.1
-------
Sections 3.3 and 3.4 of EPA 1982). However, if the surface soils contain drill cuttings or excavated
materials, fugitive dusts and sediments may be contaminated with the hazardous matter. Contamina-
tion of fugitive dusts and runoff sediments can be prevented by treating excavated material as
hazardous matter and disposing of it accordingly.
It should be noted that each pipe vent passing through a surface cap represents a possible breach of
that cap. Vent openings, therefore, should be local high spots. Even if the site is not capped, vents
represent a possible pathway for water to enter the waste area directly.
Removing the gases from the site may cause subsidence and disrupt capping or surface contouring,
thereby interfering with other remedial measures. This effect can be precluded by recognizing the risk,
inspecting the site periodically to see that subsidence has not occurred, and taking action (recontour-
ing) if it has occurred.
If the pipe vents are being used with forced ventilation, there is the additional long-term commitment
of electrical energy to provide the pumping. This is an unavoidable aspect of the use of forced
ventilation.
6.2 TRENCH VENTS
Trench vents provide a barrier against lateral migration of gases. These are deep, narrow, gravel-filled
trenches spanning part or all of the perimeter of the waste site. Gases migrate into the trenches from
which they are collected. Possible effects of the use of trench vents are summarized in Table 6.2 and
described in the good engineering practice table, Table 6.2a, at the end of this section.
During excavation of trench vents, methane concentrations may be diluted to explosive concentra-
tions. Thus, a potential hazard to the health and safety of humans and neighboring biota exists because
of the potential for fire or explosion. This unavoidable effect should be considered when preparing
excavation plans. In some cases, trench vents may be used with an air blanket pumped into the vent
(EPA 1982). Again, this can dilute methane concentrations to explosive levels causing a long-term
hazard for explosion.
TABLE 6.2. Effects of Gas-Migration Controls: Trench Vents
Ground-Water Surface-Water
Movement/ Movement/ Air
Quality Quantity Quality Quantity Quality
»HPR — ONSR
— — OHPR
— »NSR
— 3HPR
Public
Soils/ Health/ Resource
Geology Biota Safety Commitments
»HPR ONPI —
— OHPR —
— ONPR »HPR
— — »NPR
• NPI
• = Highly Probable O = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
6.2
-------
If an air blanket is used or if the trench is pumped to remove the gases, a long-term commitment of
energy resources is implied. This is an unavoidable aspect of the use of forced ventilation.
During the construction of trench vents, surface soils can be disturbed, which may lead to fugitive-dust
emissions and contribute to sediment loading in receiving waters from surface runoff. If the excavated
soils contain hazardous materials, the fugitive dust and sediments can be contaminated. The dust and
sediments can further contaminate local soils and represent a hazard to humans and neighboring biota.
The spread of contamination in this way and the associated hazards can be mitigated by treating
contaminated excavated material as hazardous matter. Emissions of uncontaminated fugitive dust can
be prevented by water spraying and other measures (see Addendum 1). Increased sediment loading of
receiving waters can be prevented by using surface-water diversion and collection measures together
with revegetation (see Sections 3.3 and 3.4 of EPA 1982).
Additionally, trenches venting to the atmosphere can emit hazardous or noxious chemicals to the air,
resulting in a degradation of local air quality and exposure of the public and biota. Such degradation
can be prevented by the use of collection and treatment facilities (see Section 6.4 of EPA 1982).
Trench vents potentially can affect ground water as well as control gas migration. Open trenches
provide a direct pathway for recharge from the surface to the waste. This is an unavoidable aspect of the
use of trench vents; hydrologic consequences of this measure should be considered during the
alternative selection process. Additionally, release of the gases could affect the integrity of capping and
other surface-water controls; this is unavoidable but can be mitigated in part by periodically inspecting
the site and, if subsidence has occurred, recontouring.
Open trenches represent a potential hazard to wildlife and people who might fall into the trench. The
hazard to people can be mitigated through fencing and other security measures to prevent the public
from entering the site. The hazard to biota cannot be avoided when using open trenches.
6.3 GAS BARRIERS
Gas barriers are used to prevent the vertical or lateral migration of gases and to assist in gas collection.
The barriers usually are used together with other methods. Possible effects of the use of gas barriers are
summarized in Table 6.3 and described in the good engineering practice table, Table 6.3a, at the end of
this section.
TABLE 6.3. Effects of Gas-Migration Controls: Gas Barriers
Ground-Water Surface-Water
Quality
Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quantity Quality Quantity Quality Geology Biota Safety Commitments
0>NSR
ONPR
dNSR —
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
6.3
-------
Creating gas barriers involves construction activities that disrupt surface soils. This can cause fugitive
dust to be raised and sediments to be carried to receiving surface waters by overland runoff. The
fugitive dusts or sediments could cause negative effects on the resident biota. Fugitive emissions can be
controlled by water spraying or other methods (see Addendum 1). Transport of sediment by overland
runoff can be prevented by using surface-water diversion and collection methods together with
revegetation (see Sections 3.3 and 3.4 of EPA 1982).
Because gas barriers will also be barriers to surface-water percolation, they will affect runoff and the
amount of water discharged to surface waters. This effect can be mitigated, if necessary, through the
use of surface-water controls, holding ponds, and percolation beds (see Section 3.4 of EPA 1982).
6.4 GAS-COLLECTION SYSTEMS
Gas-collection systems gather the gas collected in trenches or pipe vents and carry it to a point for
treatment or for use. Possible effects of the use of gas-collection systems are summarized in Table 6.4
and described in the good engineering practice table, Table 6.4a, at the end of this section.
The only direct effects of gas-collection systems are the energy commitment and noise associated with
pumping operations. Neither of these can be avoided completely if gas collectors are used. However,
the noise effects of pumping can be reduced by enclosing the pumps and/or operating the pumps on a
daily cycle such that public annoyance is minimized.
The installation of gas-collection systems involves construction activities, which can raise fugitive dusts;
these dusts can affect resident biota. The effects of fugitive dusts can be minimized by water spraying
and other measures (see Addendum 1). Disturbed areas can contribute sediments to surface runoff,
which will be discharged to receiving waters and may affect biota inhabiting those waters. These effects
can be reduced by the use of surface-water diversion and collection measures together with revegeta-
tion (see Sections 3.3 and 3.4 of EPA 1982).
TABLE 6.4. Effects of Gas-Migration Controls: Gas-Collection Systems
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
ONSR — »NPI — »NSR — «NPI
— — »NSR — — — —
• = Highly Probable 9 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
6.5 GAS TREATMENT
Gases that are collected from an uncontrolled hazardous-waste site can be treated via sorption or
thermal oxidation. In thermal oxidation, the gases are oxidized either in a self-sustaining manner
through flares or through the use of afterburners. I n methods of treatment using sorption, the gases are
6.4
-------
TABLE 6.5. Effects of Gas-Migration Controls: Gas Treatment
Ground-Water
Surface-Water
Public
Health/ Resource
Movement/ Movement/ Air Soils/
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
Flares —
Afterburners —
Sorption
Oncethrough 3HPR
Regenerated OHPR
3NPR
3HPR
3HPR
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
dNPI — — — —
O NPR — — — • NPI
— OHPR — — —
3 HSR OHPR — — »NPI
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
sorbed on activated carbon either on a once-through basis or with regeneration of the activated
carbon. Possible effects of the use of gas-treatment methods are summarized in Table 6.5 and described
in the good engineering practice tables, Tables 6.5a-c, at the end of this section.
Flares used to oxidize methane and noxious gases can degrade local air quality because these create
noxious and corrosive combustion products. The effects to air quality are irremediable if flares are
used.
Afterburners imply a long-term, irremediable commitment of fuel to oxidize the collected gases. The
combustion products can be noxious or corrosive and, therefore, can degrade air quality. The latter
effect can be remedied by the use of some sort of scrubbing system. However, the process waters from
this scrubbing system, if discharged to receiving waters, may degrade surface-water quality and
adversely affect biota inhabiting these surface waters. This can be mitigated by treating scrubbing
waters before discharge.
Once-through sorption of noxious gases on activated carbon leaves the problem of disposal of the
spent carbon. Because the carbon contains the hazardous material, it can degrade the soil and surface-
and ground-water quality if it is not properly disposed of (that is, in a RCRA site).
If the carbon is regenerated, the out gases must be collected and treated either by flare or via
afterburners. Either method then leads to the potential effects associated with the final treatment.
Activated carbon does not retain its effectiveness for an indefinite number of regeneration cycles, so
when it is spent, it must be disposed of. If improperly disposed of, it can contaminate soils and degrade
surface- or ground-water quality. Accordingly, spent carbon from a regeneration cycle should also be
handled as hazardous material.
6.6 GAS RECOVERY
Cases extracted from an uncontrolled hazardous-waste site may be recovered and used for their
thermal value. Possible effects of the recovery of gases are summarized in Table 6.6 and described in the
good engineering practice table, Table 6.6a, at the end of this section.
6.5
-------
TABLE 6.6. Effects of Gas-Migration Controls: Gas Recovery
Ground-Water
Surface-Water
Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
ONPI
N
S
R
NB:
= Highly Probable d = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigabl")
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
These gases usually are contaminated with hazardous and noxious vapors; they would be 'sweetened'
before use. The waste stream of the sweetening process will include noxious gases that also must be
disposed of, most probably through the use of flares because of the energy commitment of after-
burners. Accordingly, flaring these gases can reduce air quality.
6.6
-------
TABLE 6.1a. Gas-Migration Controls: Pipe Vents
Affected Area
Effect
Mitigation Measure
Ground-Water
Quality
Surface-Water
Quality
this measure may interfere with effectiveness
of cap or surface contouring leading to ground-
water contamination
runoff from soils disturbed during construc-
tion activities can carry sediment to receiving
waters
runoff from soils containing drill cuttings can
carry contaminated sediments to receiving
waters
Air Quality construction activities can result in release of
fugitive dusts
fugitive dusts from soils containing drill cut-
tings can be contaminated
release of toxic vapors can degrade air quality
release of anerobic decomposition products
can degrade air quality
Soils/Geology drill cuttings may contaminate soils
Biota release of toxic vapors may affect resident
biota
fugitive dust (contaminated or uncontami-
nated) from excavation can affect nearby
biota
sediment (contaminated or uncontaminated)
from activity can affect aquatic biota
Public Health contaminated fugitive dust or contaminated
or Safety sediment from activities can carry hazardous
material off site
release of toxic vapors may affect public
health
during drilling, methane may be diluted to
explosive limit, presenting risk of explosion
Resource if used with forced ventilation, a long-range
Commitment commitment of electrical energy is implied
consider possible interactions between mea-
sures; inspect and repair as required
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
see soils/geology below
fugitive-dust control (see Addendum 1)
see soils/geology below
use gas-collection and -treatment (or
-recovery) measures (see EPA 1982, Sections
6.4-6.6)
use gas-collection and -treatment (or
-recovery) measures (see EPA 1982, Sections
6.4-6.6)
contain drill cuttings; handle as hazardous
matter
see air quality above
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
see air quality above
consider this possibility when developing dril-
ling plan
none; unavoidable effect of this technology
6.7
-------
TABLE 6.2a. Gas-Migration Controls: Trench Vents
Affected Area
Effect
Ground-Water this measure may interfere with effectiveness
Quality of cap or surface contouring leading to ground-
water contamination
this measure may interfere with hydrologic
control measures
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
runoff from soils containing excavated matter
can carry contaminated sediments to receiv-
ing waters
Air Quality construction activities can result in release of
fugitive dusts
fugitive dusts from soils containing excavated
matter can be contaminated
release of toxic vapors can degrade air quality
release of anaerobic decomposition products
can degrade air quality
Soils/Geology excavated matter may contaminate soils
Biota release of toxic vapors may affect resident
biota
fugitive dust (contaminated or uncontami-
nated) from excavation can affect nearby biota
sediment (contaminated or uncontaminated)
from activity can affect aquatic biota
open trenches represent a potential hazard to
wildlife which might fall into them
Public Health contaminated fugitive dust or contaminated
or Safety sediment from activities can carry hazardous
material offsite
Mitigation Measure
consider possible interactions between
measures; inspect and repair as required
consider possible interactions between
measures
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
see soils/geology below
fugitive-dust control (see Addendum 1)
see soils/geology below
use gas-collection and -treatment measures
(see EPA 1982, Section 6.4)
use gas-collection and -treatment measures
(see EPA 1982, Sections 6.4)
contain excavated matter; handle as hazard-
ous matter
see air quality above
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
none; unavoidable aspect of open trenches
see air quality and surface-water quality above
release of toxic vapors may affect public health see air quality above
Resource
Commitment
during excavating, methane may be diluted to
explosive limit, presenting risk of explosion
open trenches represent a potential hazard for
the public who might fall into them
if used with an air blanket or if trench is
pumped, a long-range commitment of electri-
cal energy is implied
consider this possibility when developing
excavating plan
control access
none; unavoidable effect of this technology
6.8
-------
TABLE 6.3a. Gas-Migration Controls: Gas Barriers
Affected Area
Effect
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Surface-Water changes in percolation of surface water can
result in increased discharge to receiving
waters
Quality
Air Quality
Biota
construction activities can result in release of
fugitive dusts
fugitive dust from excavation can affect nearby
biota
Mitigation Measure
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
incorporate surface-water controls, holding
ponds, and percolation basins as appropriate
(see EPA 1982, Section 3.4)
fugitive-dust control (see Addendum 1)
prevention is key (see air quality above);
remediation is difficult
sediment from activity can affect aquatic biota see surface-water quality above
6.9
-------
TABLE 6.4a. Gas-Migration Controls:
Affected Area Effect
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
Air Quality construction activities can result in release of
fugitive dusts
pumping operations will generate noise
Biota fugitive dust from excavation can affect nearby
biota
sediment from activity can affect aquatic biota
Resource pumping operations imply a commitment of
Commitment electrical energy
Gas-Collection Systems
Mitigation Measure
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
fugitive-dust control (see Addendum 1)
none; unavoidable effect of this technology;
if possible operate on cycle to minimize effect
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
none; unavoidable effect of this technology
6.10
-------
TABLE 6.5a. Gas-Migration Controls: Gas Treatment—Flares
Affected Area Effect Mitigation Measure
Air Quality noxious or corrosive combustion products none; unavoidable
may degrade air quality
6.11
-------
TABLE 6.5b. Gas-Migration Controls: Gas Treatment—Afterburners
Affected Area Effect Mitigation Measure
Surface-Water scrubber waste water can degrade quality of treat scrubber waste water before discharge
Quality receiving waters
Air Quality noxious or corrosive combustion products use scrubber (see surface-water quality above)
may degrade air quality
Resource long-term commitment to supply fuel tooxid- none; unavoidable aspect of this technology
Commitment ize collected gases
6.12
-------
TABLE 6.5c. Gas-Migration Controls: Gas Treatment—Carbon Sorption
Affected Area Effect Mitigation Measure
Ground-Water disposal of spent carbon can result in ground- dispose of in a RCRA-approved site
Quality water contamination
Surface-Water disposal of spent carbon can result in surface- dispose of in a RCRA-approved site
Quality water contamination
Air Quality regeneration of carbon releases toxic vapors use flare or afterburner (see EPA 1982, Section
which can degrade air quality 6.5)
Soils/Geology disposal of spent carbon can result in soil dispose of in a RCRA-approved site
contamination
6.13
-------
TABLE 6.6a. Gas-Migration Controls: Gas Recovery
Affected Area Effect Mitigation Measure
Air Quality flaring of extracted noxious gases can degrade none; unavoidable
air quality
6.14
-------
7.0 DIRECT-TREATMENT METHODS
Direct treatment methods involve control of the pollutant source, rather than control of the transport
medium. Direct treatment involves one or more of the following:
• physical removal together with disposal in a more suitable location,
• physical removal followed by stabilization or destruction, or
• in situ treatment.
7.1 EXCAVATION
Excavation involves the removal for further treatment of the hazardous waste from an uncontrolled
site. The potential effects associated with excavation are summarized in Table 7.1 and described in the
good engineering practice table, Table 7.1a, at the end of this section.
When excavating dry matter, the construction-type activities used can cause noise and fugitive dust.
The noise is an irremediable effect; it can be mitigated in part by operating only during normal daylight
working hours. Fugitive dust may be contaminated by the wastes and spread hazardous matter to other
areas if not controlled. Contaminated or uncontaminated fugitive dust can affect resident biota.
Uncontaminated fugitive dusts can be controlled by water spraying and other methods. Because
sprinkling is only about 50% effective, highly contaminated fugitive dust may have to be controlled by
other methods. For instance, an enclosure could be erected around the site during the excavation
activities. (See Addendum 1.)
The construction activities will disturb the surface; therefore, contaminated or uncontaminated
sediments may be contributed to receiving water via runoff. These sediments can adversely affect
aquatic biota. Surface-water diversion and collection controls and revegetation can be used to prevent
the degradation of surface-water quality (see Sections 3.3 and 3.4 of EPA 1982).
TABLE 7.1. Direct-Treatment Methods: Excavation
Ground-Water
Surface-Water
Quality
Dry-Matter
Wet-Matter/
Sludge
Movement/
Quantity
Quality
Movement/ Air
Quantity Quality
3NSR
OHPR
Soils/
Geology Biota
Public
Health/ Resource
Safety Commitments
»NSR 3HPR »HPR 0>NSI
0>HPR — ONSR 0>HSR
»NSI — — 3HPR
»NSI OJHPR 0)HPR »NSI
»HPI — dNSR 0>HPR
O HPR — »HSR
N
S
R
NB:
= Highly Probable 3 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
7.1
-------
Additional adverse effects that the exhumation of dry matter can cause include releases to the
atmosphere of evaporating materials (including potentially hazardous materials) and the potential for
fire and/or explosion. Evaporation of volatiles is an unavoidable aspect of waste excavation. Excavation
activities can release explosive concentrations of waste materials or expose pyrophoric matter. Fire or
explosion would be likely to release hazardous matter beyond the confines of the waste site, thereby
contaminating soils and forming a health and safety hazard for humans and biota. The potential for
exposing explosive or pyrophoric matter should be considered when preparing the excavation plan.
When excavating wet matter, liquids and sludges must be removed from lagoons or holding basins.
When this wet matter is removed, waters will seep from the spoils. These waters will be contaminated
with some of the hazardous material and can, in turn, contaminate surface water, ground water, or
soils.
Prevention of the release of dewatering liquids is the appropriate mitigative action; these waters
should be contained and held for treatment as hazardous matter. I n addition, the process of excavating
the sludges can cause additional breaches of the containment, allowing contaminated matter to reach
ground water. This effect is mitigated by taking care during the excavation process, and excavating
sufficient material to ensure that all contaminated matter has been removed.
During the handling of the hazardous material, wet or dry, the potential for spills exists. Although spills
should be avoided through careful handling of the contaminated matter, their potential should be
recognized and procedures for identifying and removing these should be implemented.
Other effects inherent to the handling and/or the disposal of the hazardous waste are caused by the
traffic associated with off-site removal. This traffic creates a short-term irremediable noise effect and
forms a potential traffic safety hazard. The transport of hazardous matter to disposal sites may result in
releases. A fraction of the material hauled can be expected to be released as contaminated fugitive
dust. This can be minimized by hauling the excavated matter in containers. An accident could result in a
major release of material.
7.2 HYDRAULIC DREDGING
Hydraulic dredging can be used to physically remove contaminated material. The potential effects
associated with hydraulic dredging are summarized in Table 7.2 and described in the good engineering
practice table. Table 7.2a, at the end of this section.
Using this direct method, leaks from pumps and/or conduits (hose or piping) can contaminate soils or
surface water. This effect can be avoided by observing the removal process carefully and treating any
such releases as spills of hazardous material. In addition, runoff material from dredged matter can
contaminate soils, surface water, or ground water. This contamination can be prevented by containing
dredge-spoil runoff and treating it as hazardous matter. The hydraulic-dredging process may damage
the existing confinement, resulting in releases to ground water. This effect can be prevented by
removing enough material to ensure that no contaminated matter remains.
Construction-like activities will disturb surface soils. Fugitive dusts will be raised; if these soils have
been contaminated by spills or leaks, the fugitive dusts may be contaminated. Fugitive dusts can
adversely affect resident biota; contaminated fugitive dusts can be carried off site and affect the public.
Fugitive dust emissions can be controlled by various methods (see Addendum 1.1).
7.2
-------
TABLE 7.2. Direct-Treatment Methods: Hydraulic Dredging
Ground-Water Surface-Water
Movement/ Movement/ Air
Quality Quantity Quality Quantity Quality
OHPR
»HPR
• NSR
3HSI
(iHPR
Soils/
Geology Biota
Public
Health/ Resource
Safety Commitments
»HPR
OHPR ONSI
dNSR C»HPR
N
S
R
NB:
= Highly Probable
-------
TABLE 7.3. Direct-Treatment Methods: Land Disposal
Ground-Water
Surface-Water
Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
Land Fill
OHPR
Surface
Impoundment OHPR
Land
Application
OHPR
(BNSR
OHPR
OHPR
ONSR
OHPR
• NSR OHPR ONSR OHPR • NPI
OHSR — OHPR — —
OHPI OHPR OHPR OHPR • NPI
• NSR — ONSR — —
• HPR OHPR OHPR — • NPI
• = Highly Probable O = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
and create an offensive odor in the surrounding area. Using this method, surface soils are highly
disturbed, so they can form a source of fugitive dusts, both contaminated and uncontaminated. These
air pollution effects are integral to the land-application method and cannot be avoided or mitigated
within this method. The release of fugitive dusts can be minimized by properly choosing weather
conditions for tilling and maintaining moist soil conditions.
Because the surface soils are disturbed, runoff controls and sedimentation basins (see Section 3.4 of
EPA 1982) will be required to prevent the transport of contaminated sediments to receiving waters by
overland flow. Since wastes are applied directly to the surface, contamination of ground water is of
concern. Ground-water contamination can be prevented only by careful design of the land application
to ensure that 1) the design does not overwhelm the capacity of the land to destroy the material and
2) the process is monitored to determine that it is working as designed and no migration off site is
occurring. Particular design attention should be given to abnormal weather conditions that may affect
recharge or microbial activity and, therefore, may lead to contamination of ground water. Cauti an is
advised in the cultivation of feed or food crops in soils being used or which have been used for land
application to avoid plant uptake and the bioaccumulation of hazardous materials which may be
passed through the food chain.
7.4 SOLIDIFICATION
Solidification is a process of consolidating the hazardous-waste material before secure disposal, either
on site or off. It is not a disposal alternative in itself, but rather a component in an alternative. The
potential effects associated with solidification are summarized in Table 7.4 and described in the good
engineering practice tables, Tables 7.4a-f, at the end of this section.
Solidifying the waste using cement-based, lime-based, or self-cementing solidification processes can
raise fugitive dusts during the handling of the solidifying material. This is probably irremediable,
because the materials are finely divided and must be handled when dry. In addition, because the
7.4
-------
TABLE 7.4. Direct-Treatment Methods: Solidification
Ground-Water
Surf ace-Water
Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
Cement-Based
Lime-Based
OHPR —
— —
— — O HSR
— — ONSI
— — OHSR
— — ONSI
OHPR
OHPR
Thermoplastic-
Based — — —
Organic
Polymer-Based OHSR — OHSR
Self-Cementing — — —
Classification — — —
• = Highly Probable O = Probable
N = Nuisance H = Hazardous
S = Short-term (construction phase only)
R = Reversible (or mitigable)
NB: Multiple entries in a category indicate that several
OHSR OHPR — — »NSI
— OHPR — — —
OHSR OHPR — — «NSI
ONSI — — — —
OHSR OHPR — — »NSI
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
1 = Irreversible (unmitigable)
different types of effects are foreseen as possible.
hazardous material may need to be dried in the cement-based, lime-based, thermoplastic-based,
self-cementing, and glassification processes, hazardous matter may be emitted during the drying
process, either as fugitive dusts or as vapors.
Waste materials such as fly ash, bottom ash and slag, furnace slag, and incinerator residue are
commonly used materials for solidifying liquid or sludge matter in a pit or lagoon. As noted in Section
3.1 of this guide, these materials commonly contain heavy metals and other objectionable matter which
can contribute to contamination. Additionally, these materials can change ground-water chemistry so
as to mobilize components that may have been fixed in the waste. This potential for ground-water
contamination can be reduced by characterization of soil, waste, and combustion-residue chemistry to
determine if the potential for a problem exists.
7.5 ENCAPSULATION
Encapsulation is a process by which the hazardous matter is physically enclosed within a container. The
potential effects associated with encapsulation are summarized in Table 7.5 and described in the good
engineering practice table, Table 7.5a, at the end of this section.
Potential adverse effects are the emissions and spills occurring during the handling process. The
emissions of fugitive dust or vapors are probably irremediable. Spills should be taken into considera-
tion and treated as part of the cleanup activity.
As part of the encapsulation process, the containers will be fused. This process involves the commit-
ment of energy.
7.5
-------
TABLE 7.5. Direct-Treatment Methods: Encapsulation
Ground-Water Surface-Water PuWic
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
3HSI
OHPR — —
INSI
N
S
R
NB:
= Highly Probable d = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
7.6 IN SITU TREATMENT
For in situ treatment, wastes are treated in place or removed with minimal soil disruption. In situ
treatment processes include surface solution mining, neutralization/detoxification, and microbial
degradation. The potential effects associated with in situ treatment are summarized in Table 7.6 and
described in the good engineering practice tables, Tables 7.6a-c, at the end of this section.
7.6.1 In Situ Treatment—Solution Mining
In solution mining, the wastes are removed by flushing them out of the soil using water, acidic or basic
solutions, or complexing or chelating agents. The leachate thus generated is collected and removed for
treatment.
TABLE 7.6.1 Direct-Treatment Methods: In-Situ Treatment—Solution Mining
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
Water
Acid
Alkali
Complexing/
Chelating
9 HSR
OHSR
3HSR
3 HSR
9NSI
9HSI
ONSI
3HSI
ONSI
OHSI
— 0>NSI —
— ONSI —
— 0>NSI —
N
S
R
NB:
= Highly Probable 0> = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
7.6
-------
Contamination of ground water by any of the possible elutriates, is a major concern. The use of solution
mining contains as an article of faith that the leachate will be collected. Because inhomogeneities or
uncertainties in the hydrologic system can allow leachate to pass uncollected, ground-water contami-
nation is a real concern. This effect is remediable, but only via ground-water treatment (see Section 4 of
EPA 1982) if it occurs.
Releases of the elutriating agent, if other than water, also can cause atmospheric pollution through
vaporization. Other sources of air pollution are reaction products occurring as a result of uncontrolled
reactions between the elutriate and the waste. These sources of air pollution are integral to the method
and the reagents involved and cannot be mitigated.
Finally, some chelating agents are themselves somewhat toxic and may damage existing biota. Once
again, the effects of these solvents are integral to the method used and probably cannot be mitigated.
7.6.2 In Situ Treatment—Neutralization/Detoxification
Neutralization/detoxification is the technique of applying or injecting into the uncontrolled waste
disposal site a substance that immobilizes or destroys the contaminant. This method can produce a
leachate that may contaminate ground water with the hazardous material or with the reagent itself. In
addition, immobilized material could be remobilized by subsequent ranges in soil chemistry. (For
instance, an oxidation by bacteria causing the remobilization of heavy metal ions.) If such leachate
reaches the ground water, it would be a potential hazard for human health and safety and could be
remedied only via ground-water treatment methods. Monitoring ground-water quality to detect
possible contamination should be an integral part of this method.
The reagents used to neutralize and/or detoxify wastes may be volatile and form air pollutants.
U ncontrolled or unexpected reaction between the reagents and the waste matter may release hazard-
ous matter to the atmosphere. The rate of release will be controlled in part by ambient surface
conditions. Also, neutralization and detoxification reagents may be toxic to local biota. The effects of
this toxicity are inherent to the method and are probably not otherwise mitigable, but should be
recognized.
TABLE 7.6.2 Direct-Treatment Methods: In-Sit j Treatment—Neutralization/Detoxification
Ground-Water Surface-Water
Movement/ Movement/
Quality Quantity Quality Quantity
OHSR — — OHSI
• NSR — — ONSI
• HPR — — —
• = Highly Probable 9 = Probable
N = Nuisance H = Hazardous
S = Short-term (construction phase only)
R = Reversible (or mitigable)
NB: Multiple entries in a category indicate that
Air
Quality
several c
Soils/
Geology
Biota
Public
Health/ Resource
Safety Commitments
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
7.7
-------
7.6.3 In Situ Treatment—Mkrobial Degradation
Microbial degradation involves an enhancement of natural biodegradation by seeding the site with
appropriate bacteria or other microorganisms, adding nutrients or chemical buffers, and aerating.
Because microbial degradation is a slow process, the waste matter may leach out of the soil and
contaminate ground water before degradation is complete. This effect, if it occurs, is remediable only
via ground-water cleanup (see Section 4.0 of EPA 1982). Nutrients added to assist the microbial
degradation process can themselves contaminate ground water with nontoxic contaminants. The latter
effect is also remediable only through ground-water cleanup.
TABLE 7.6.3 Direct-Treatment Methods: In-Situ Treatment—Microbial Degradation
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
dHSR — — — ____ _
dNPR _ _ ______
• = Highly Probable 9 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
7.7 OTHER DIRECT TREATMENT METHODS
Other direct treatment methods include molten-salt destruction and plasma reduction processes. In
the molten-salt process, the contaminated material is injected into a molten salt where it is destroyed.
In plasma reduction, the material is injected into a plasma (an electrical discharge in a gas) where the
contaminants are destroyed. The potential effects associated with other direct treatment methods are
summarized in Table 7.7 and described in the good engineering practice table, Table 7.7a, at the end of
this section.
For each of these processes, the major effect is the commitment of energy resources, because both
methods are very energy intensive. This energy commitment is unavoidable.
Emissions of the hazardous material may occur during the handling and injection processes and spills
may occur during the handling process. Emissions of the hazardous materials are probably irremedi-
able. Spills should be anticipated and cleaned up before the site is deemed to have been restored.
7.8
-------
TABLE 7.7 Direct-Treatment Methods: Others
Ground-Water
Surface-Water
Quality
Molten Salt
Plasma
Reduction
Movement/
Quantity
Quality
Movement/
Quantity
Air
Quality
3HSI
Soils/
Geology
Biota
9HPR —
3HSI OHPR —
Public
Health/ Resource
Safety Commitments
— »NSI
— • NSI
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
7.9
-------
-------
TABLE 7.1a. Direct-Treatment Methods: Excavation
Affected Area
Effect
Mitigation Measure
Ground-Water dewatering off waters can contaminate ground
Quality waters
excavation process can further breach original
containment allowing contaminants to reach
ground water
Surface-Water runoff from soils disturbed during excavation
Quality activities can carry sediment to receiving
waters
dewatering off waters can contaminate sur-
face waters
Air Quality excavation activities can result in release of
fugitive dusts
excavation of contaminated matter can con-
taminate soils, which can become contami-
nated fugitive dusts
construction-like activities will produce noise
evaporating hazardous matter can reduce air
quality
off-site haulage of exhumed matter can result
in airborne releases
Soils/Geology spills of exhumed matter can contaminate soils
exhumation of pyrophoric or flammable
material can result in fire or explosion which
can contaminate soils beyond original extent
contain dewatering liquids; treat as hazardous
matter
excavation process should remove enough
matter to ensure that all contaminated mate-
rial is removed
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
see ground-water quality above
fugi ive dust control (see Addendum 1)
control contaminated fugitive dust (see
Addendum 1)
schedule activities to minimize effects
none; unavoidable aspect of waste exhumation
haul material in closed containers or covered
trucks
spills should be expected and spill cleanup
incorporated in operating plan
see public health or safety below
dewatering off waters can contaminate soils see ground-water quality above
Biota
fugitive dust (contaminated or uncontami-
nated) from excavation can affect nearby biota
sediment (contaminated or uncontaminated)
from excavation can affect aquatic biota
Public Health contaminated fugitive dust or contaminated
or Safety sediment from excavation activities can carry
hazardous material off site
exhumation of flammable, explosive, or pyro-
phoric matter could result in fire or explosion
haulage of excavated matter for disposal can
present traffic safety hazard
accident involving truck hauling exhumed
matter can represent major release
prevention is key (see air quality above);
remediation difficult
see surface-water quality above
see air quality and surface-water quality above
establish and enforce operating procedures
that include this possibility
schedule and route hauling to minimize traffic
risks
include possibility of such an accident in con-
tingency planning; route hauling to minimize
effect
7.11
-------
TABLE 7.2a. Direct-Treatment Methods: Hydraulic Dredging
Affected Area
Effect
Mitigation Measure
Ground-Water dewatering off waters can contaminate ground
Quality waters
dredging process can further breach original
containment allowing contaminants to reach
ground water
Surface-Water dewatering off waters can contaminate sur-
Quality face waters
Air Quality dredging activities can result in release of fugi-
tive dusts
spills or leaks of contaminated matter can con-
taminate soils, which can become contam-
ianted fugitive dusts
evaporating hazardous matter can reduce air
quality
off-site haulage of exhumed matter can result
in airborne releases
Soils/Geology spills of exhumed matter or leaks from pumps
and lines can contaminate soils
contain dewatering liquids; treat as hazardous
matter
dredging process should remove enough mat-
ter to ensure that all contaminated material is
removed
see ground-water quality above
fugitive-dust control (see Addendum 1)
control contaminated fugitive dust (see
Addendum 1)
none; unavoidable aspect of waste exhumation
haul material in closed containers or covered
trucks
spills and leaks should be expected and spill
cleanup incorporated in operating plan
Biota
Public Health
or Safety
dewatering off waters can contaminate soils see ground-water quality
fugitive dust (contaminated or uncontami-
nated) from dredging can affect nearby biota
sediment (contaminated or uncontaminated)
from dredging can affect aquatic biota
contaminated fugitive dust or contaminated
sediment from dredging activities can carry
hazardous material off site
haulage of excavated matter can result in traf-
fic noise
haulage of excavated matter for disposal can
present traffic safety hazard
accident involving truck hauling exhumed
matter can represent major release
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
see air quality and surface-water quality above
schedule and route hauling to minimize traffic
risks
schedule and route hauling to minimize traffic
risks
include possibility of such an accident in con-
tingency planning;route hauling to minimize
effect
7.12
-------
TABLE 7.3a. Direct-Treatment Methods: Land Disposal—Landfilling
Affected Area Effect Mitigation Measure
Ground-Water leak of material can contaminate ground use a RCRA-approved site
Quality water
Surface-Water runoff from soils disturbed during excavation incorporate surface-water diversion and col-
Quality activities can carry sediment to receiving lection measures with revegetation as appro-
waters priate (see EPA 1982, Sections 3.3 and 3.4)
release of material can contaminate surface use a RCRA-approved site
water
Air Quality landfilling activities can result in release of fug- fugitive-dust control (see Addendum 1)
itive dusts
evaporating hazardous matter can reduce air use a RCRA-approved site
quality
Soils/Geology releases from landfill can contaminate soils use a RCRA-approved site
release of matter from landfill can expose use a RCRA-approved site
biota to hazardous waste
Biota fugitive dust from landfilling can affect nearby prevention is key (see air quality above);
biota remediation is difficult
sediment from landfilling can affect aquatic see surface-water quality above
biota
Public Health release of matter from landfill can expose pub- use a RCRA-approved site
or Safety lie to hazardous matter
Resource land is committed to use as hazardous waste none; unavoidable aspect of this technology
Commitment disposal site for an indefinite period
7.13
-------
TABLE 7.3b. Direct-Treatment Methods: Land Disposal—Surface Impoundment
Affected Area Effect Mitigation Measure
Ground-Water leak of material can contaminate ground use a RCRA-approved site
Quality water
Surface-Water runoff from disturbed soils during excavation incorporate surface-water diversion and col-
Quality activities can carry sediment to receiving waters lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
release of material can contaminate surface use a RCRA-approved site
water
Air Quality construction activities can result in release of fugitive-dust control (see Addendum 1)
fugitive dusts
evaporating hazardous matter can reduce air use a RCRA-approved site
quality
Soils/Geology releases from impoundment can contaminate use a RCRA-approved site
soils
release of material from impoundment can use a RCRA-approved site
expose biota to hazardous substances
Biota fugitive dust from construction can affect prevention is key (see air quality above);
nearby biota remediation is difficult
sediment from construction can affect aquatic see surface-water quality above
biota
Public Health release of matter can expose public to hazard- use a RCRA-approved site
or Safety ous substances
Resource land is committed to use as hazardous waste none; unavoidable aspect of this technology
Commitment disposal site for an indefinite period
7.14
-------
TABLE 7.3c. Direct-Treatment Methods: Land Disposal—Land Application
Affected Area
Effect
Ground-Water material can contaminate ground water
Quality
Surface-Water runoff from highly disturbed soils can carry
Quality contaminated sediment to receiving waters
Air Quality disturbed soils can be source of contaminated
fugitive dusts
evaporating hazardous matter can reduce air
quality
Soils/Geology soils will be contaminated with hazardous
matter
Biota inadvertant release can expose biota to
hazardous matter
Public Health release of matter can expose public to hazard-
or Safety ous matter
if vegetation grown on soil enters food chain,
it can expose public to hazardous matter
Resource land is committed to use as hazardous waste
Commitment disposal site for an indefinite period
Mitigation Measure
design carefully; establish procedures for
monitoring; consider possibility of abnormal
weather conditions
incorporate surface-collection measures as
appropriate (see EPA 1982, Sections 3.3 and
3.4)
maintain moist soil conditions; establish and
enforce procedures for scheduling tilling
activities
none; unavoidable aspect of this technology
none; unavoidable aspect of this technology
prevention: see ground-water quality, surface-
ater quality, and air quality above
prevention: see ground-water quality, surface-
water quality, and air quality above
establish and enforce procedures to ensure
that vegetation does not enter food chain
none; unavoidable aspect of this technology
7.15
-------
TABLE 7.4a. Direct-Treatment Methods: Solidifaction—Cement-Based Methods
Affected Area Effect Mitigation Measure
Ground-Water useof combustion waste matter for solidifying characterize soil, waste, and combustion
Quality contents of pit or lagoon can result in ground- chemistry to determine whether this will be a
water contamination problem
Air Quality handling of solidifying material can result in none; unavoidable
release of fugitive dusts
drying process may release hazardous vapors none; unavoidable
or fugitive dusts
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
7.16
-------
TABLE 7.4b. Direct-Treatment Methods: Solidification—Lime-Based Methods
Affected Area Effect Mitigation Measure
Air Quality handling of solidifying material can result in none; unavoidable
release of fugitive dusts
drying process may release hazardous vapors none; unavoidable
or fugitive dusts
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
7.17
-------
TABLE 7.4c. Direct-Treatment Methods: Solidification—Thermoplastic-Based Method
Affected Area Effect Mitigation Measure
Air Quality drying process may release hazardous vapors none; unavoidable
or fugitive dusts
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
Resource process uses heat energy for solidification none; unavoidable aspect of this technology
Commitment
7.18
-------
TABLE 7.4d. Direct-Treatment Methods: Solidification—Organic-Polymer-Based Methods
Affected Area Effect Mitigation Measure
Ground-Water weep waters evolved during curing process contain weep waters and handle as contami-
Quality can contaminate ground water nated matter
Surface-Water weep waters evolved during curing process see ground-water quality above
Quality can contaminate receiving waters
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
7.T9
-------
TABLE 7.4e. Direct-Treatment Methods: Solidification—Self-Cementing Methods
Affected Area Effect Mitigation Measure
Air Quality handling of solidifying material can result in none; unavoidable
release of fugitive dusts
drying process may release hazardous vapors none; unavoidable
or fugitive dusts
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
Resource self-cementing process requires significant none; unavoidable aspect of technology
Commitment energy input
7.20
-------
TABLE 7.4f. Direct-Treatment Methods: Solidification—Classification Methods
Affected Area Effect Mitigation Measure
Air Quality drying process may release hazardous vapors none; unavoidable
or fugitive dusts
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
Resource glassification process consumes significant none; unavoidable aspect of technology
Commitment amount of energy
7.21
-------
TABLE 7.5a. Direct-Treatment Methods: Encapsulation
Affected Area Effect Mitigation Measure
Air Quality handling process may release hazardous vapors none; unavoidable
or fugitive dusts
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
Resource fusing of containers consumes significant none; unavoidable aspect of this technology
Commitment amount of energy
7.22
-------
TABLE 7.6a. Direct-Treatment Methods: In Situ Treatment—Solution Mining
Affected Area Effect Mitigation Measure
Ground-Water elutriate can contaminate ground water design carefully; establish procedures for
Quality monitoring; consider possibility of abnormal
weather conditions; treat ground-water if
contamination occurs (see EPA 1982, Section 4)
Air Quality vaporizing elutriate can reduce air quality none; unavoidable aspect of this technology
uncontrolled reaction between elutriate and none; unavoidable aspect of this technology
waste matter can result in release of hazardous
matter
Biota some elutriate components toxic to biota none; unavoidable if those agents are used
7.23
-------
TABLE 7.6b. Direct-Treatment Methods: In Situ Treatment—Neutralization/Detoxification
Affected Area
Effect
Mitigation Measure
Ground-Water reaction can produce leachate that can con-
Quality laminate ground water
immobilized material may subsequently be
mobilized by change in soil chemistry and
contaminate ground water
Air Quality evaporating reagents can reduce air quality
uncontrolled reaction between reagent and
waste matter can result in release of hazardous
matter
Biota
some reagents toxic to biota
careful design; establish procedures for
monitoring; if ground-water contamination
occurs, ground-water treatment may be
required (see EPA 1982, Section 4)
monitor; if contamination occurs, ground-
water treatment may be required (see EPA
1982, Section 4)
none; unavoidable aspect of this technology
none; unavoidable aspect of this technology
none; unavoidable if those agents are used
7.24
-------
TABLE 7.6c. Direct-Treatment Methods: In Situ Treatment—Microbial Degradation
Affected Area Effect Mitigation Measure
Ground-Water waste matter can leach before degradation is design carefully; establish procedures for
Quality complete and contaminate ground water monitoring; consider possibility of abnormal
weather conditions; if ground-water contam-
ination occurs, ground-water treatment may
be required (see EPA 1982, Section 4)
nutrients added to assist microbial growth may monitor; if contamination occurs, ground-
contaminate ground water water treatment may be required (see EPA
1982, Section 4)
7.25
-------
TABLE 7.7a. Direct-Treatment Methods: Other Direct Treatment Methods—Molten-Salt Process
Affected Area Effect Mitigation Measure
Air Quality handling process may release hazardous vapors none; unavoidable aspect of this technology
or fugitive dusts
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
Resource molten-salt process consumes significant none; unavoidable aspect of this technology
Commitment amount of energy
7.26
-------
TABLE 7.7b. Direct-Treatment Methods: Other Direct Treatment Methods—Plasma-Reduction Process
Affected Area Effect Mitigation Measure
Air Quality handling process may release hazardous vapors none; unavoidable aspect of this technology
or fugitive dusts
Soils/Geology spills of contaminated matter may contami- spills should be expected and spill cleanup
nate soils incorporated in operating plan
Resource plasma-reduction process consumes significant none; unavoidable aspect of this technology
Commitment amount of electrical energy
7.27
-------
8.0 CONTAMINATED WATER AND SEWER LINES
Contamination of sewer and water lines can occur as a result of infiltration of contaminated ground
water or as the result of illegal dumping. When contamination of sewer or water lines occurs, three
basic remedial options are available: in-place cleaning, in-place leak detection and repair, or removal
and replacement.
8.1 IN SITU CLEANING
Contaminants may be removed from water or sewer lines in situ by mechanical and hydraulicscouring,
bucket dredging and suction cleaning, or chemical treatment. The possible effects of these activities
are summarized in Table 8.1 and described in the good engineering practice table, Table 8.1a, at the
end of this section.
For each of these methods, the potential exists for hazardous material to be released to the atmosphere
or spilled during the handling process. The potential for atmospheric releases is quite small, but spills
can be expected, and should be planned for, and remedied by cleaning up and treating the spilled
matter as contaminated soil.
Additionally, a certain amount of noise and traffic disruption will occur during the cleaning process.
These effects are integral to such an operation and can only be partially mitigated by operating during
normal daylight hours and avoiding, to the extent possible, traffic disruptions during rush hours.
TABLE 8.1. Contaminated Water and Sewer Lines: In Situ Cleaning
Ground-Water Surface-Water
Movement/ Movement/ Air
Quality Quantity Quality Quantity Quality
• NSI
OHSI
• NSR
Soils/
Geology Biota
OHPR —
Public
Health/ Resource
Safety Commitments
• NSI —
• = Highly Probable 3 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
8.2 LEAK DETECTION AND REPAIRS
Detecting and repairing leaks involves sewer inspection, poisoning of intruding roots with copper
sulfate or other appropriate herbicide, and grouting or relining and sleeving. The possible effects of
leak detection and repair are summarized in Table 8.2 and described in the good engineering practice
table, Table 8.2a, at the end of this section.
During leak detection and repair, the potential exists for material to be released to the atmosphere or
spilled during the operation. The potential for atmospheric releases is quite small, but spills can be
expected, and should be planned for, and remedied by cleaning up and treating the spilled matter as
contaminated soil.
8.1
-------
TABLE 8.2. Contaminated Water and Sewer Lines: Leak Detection and Repairs
Ground-Water
Movement/
Quality Quantity
Surface-Water
Movement/ Air
Quality Quantity Quality
ONSR
• NSI
OHSI
• NSR
Soils/
Public
Health/
Resource
Geology Biota Safety Commitments
(JHPR —
>NSI
N
S
R
NB:
= Highly Probable 3 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
Additionally, a certain amount of noise and traffic disruption will occur during the leak detection and
repair process. These effects are integral to such an operation and can only be partially mitigated by
operating during normal daylight hours and avoiding, to the extent possible, traffic disruptions during
rush hours.
An additional effect can occur if the root poison used enters the sewage treatment system. This can
cause an upset at the sewage treatment facility, resulting in noxious emissions and transitory release of
less-than-fully-treated sewage to receiving waters.
8.3 REMOVE AND REPLACE
Removing contaminated sewer or water lines and replacing these with new lines or moving the lines
are major construction activities. These activities may involve excavation into contaminated media. The
possible effects of the remove-and-replace option are summarized in Table 8.3 and described in the
good engineering practice table, Table 8.3a, at the end of this section.
TABLE 8.3. Contaminated Water and Sewer Lines: Remove and Replace
Ground-Water
Surface-Water
Public
Health/ Resource
Movement/ Movement/ Air Soils/
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
OHPR
3HPR
ONSR
3HPR 3HPR 3HPR 3HPR
• NSR — »NSR »NSR
•
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
= Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
8.2
-------
Removal of incompletely drained sewer pipes can readily result in the contamination of adjacent soils
(if not already contaminated). In an extreme case, this might result in ground-water contamination.
This effect can be prevented by in situ cleaning before the removal operation (see Section 8.2 of EPA
1982).
The major construction activities associated with removal and replacement of contaminated sewer or
water lines will involve disruption of the surface. If the line passes under sensitive areas such as roads,
parks, forests, wetlands, or critical habitat, removal and replacement will disrupt surface growth,
surface structures, and interfere with human and wildlife activities for the period of the activity.
Restoration of vegetation to the original state may be costly and may take an extended period.
Disruption of human activity will evoke public resistance and will probably require the commitment to
restore surface conditions to the original condition. Wildlife patterns could be disrupted permanently.
Disruption of the surface is concommitant to the remove-and-replace option and the appropriate
restoration activities are the only mitigation.
The construction activities can result in contaminated and uncontaminated fugitive dusts being
released and transported off site where these can contaminate soils and form a hazard to human health
and safety and biota. Fugitive dust can be controlled by water spraying and other control techniques
(see Addendum 1).
The construction activities can also result in contaminated or uncontaminated sediments running off
site and onto neighboring lands or into receiving waters where they can affect biota and human health
and safety. This effect can be prevented by the use of surface-water diversion and collection controls
(EPA 1982).
Construction activities also will result in noise and disruptions of traffic. These effects can be mitigated
in part by operating only during normal daylight hours.
8.3
-------
TABLE 8.1a. Contaminated Water and Sewer Lines: In Situ Cleaning
Affected Area Effect Mitigation Measure
Air Quality atmospheric release of hazardous matter is none; unavoidable but improbable
possible during handling
Soils/Geology spills of material removed from the lines can plan for spills; clean up and treat spilled matter
contaminate soils as contaminated soil
Public Health noise and traffic disruption can be expected schedule operations to reduce effects of noise
or Safety and reduce traffic disruption
8.5
-------
TABLE 8.2a. Contaminated Water and Sewer Lines: Leak Detection and Repairs
Affected Area Effect Mitigation Measure
Air Quality atmospheric release of hazardous matter is none; unavoidable but improbable
possible during handling
Surface-Water root poisons may cause upset at sewage treat- consider effect of root poison on sewage
Quality ment facility resulting in release of less-than- treatment; may be unavoidable
fully-treated sewage
Soils/Geology spills of material removed from the lines can plan for spills; clean up and treat spilled matter
contaminate soils as contaminated soil
Public Health noise and traffic disruption can be expected schedule operations to reduce effects of noise
or Safety and reduce traffic disruption
8.6
-------
TABLE 8.3a. Contaminated Water and Sewer Lines: Remove and Replace
Affected Area
Effect
Mitigation Measure
Ground-Water spills from incompletely drained sewer lines
Quality can contaminate ground waters
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
runoff can carry contaminated soils as sedi-
ment to receiving waters
Air Quality construction activities can result in release of
fugitive dusts
excavation to sewer line can bring contami-
nated soils to surface where these can become
contaminated fugitive dusts
removal of incompletely drained sewer line
can contaminate surface soils, which can
become contaminated fugitive dusts
construction activities will result in noise
Soils/Geology spills from incompletely drained sewer lines
can contaminate soils
Biota fugitive dust (contaminated or uncontami-
nated) from excavation can affect nearby biota
sediment (contaminated or uncontaminated)
from excavation can affect aquatic biota
biota will be disturbed in area of construction
activity
Public Health contaminated fugitive dust or contaminated
or Safety sediment from excavation activities can carry
hazardous material off site
excavation of buried lines may result in traffic
disruption
in situ cleaning before removal (see EPA 1982,
Section 8.2)
incorporate surface-water diversion and col-
lection measures with revegetation as approp-
riate (see EPA 1982, Sections 3.3 and 3.4)
see ground-water quality above
fugitive-dust control (see Addendum 1)
control contaminated fugitive dust (see
Addendum 1)
see ground-water quality above
none; unavoidable; schedule operations to
reduce the effect
see ground-water quality above
prevention is key (see air quality above);
remediation is difficult
see surface-water quality above
none; unavoidable but temporary if area
revegetated; wildlife patterns may be per-
manently affected
see air quality and surface-water quality above
schedule operations to minimize effect
8.7
-------
9.0 CONTAMINATED SEDIMENTS
Sediments in or adjacent to surface water may become contaminated as a result of migration from an
uncontrolled hazardous-waste site. This section describes the effects of removing these sediments (by
mechanical dredging or low-turbidity hydraulic dredging), managing dredge spoils, and revegetating
wetlands from which the sediment may have been removed. It should be noted that the choice of
mechanical dredging or low-turbidity hydraulic dredging is specific to the site. As discussed in EPA
1982, mechanical dredging is applicable under a limited set of circumstances; under other circumstan-
ces, hydraulic dredging is required.
9.1 MECHANICAL DREDGING
Mechanical dredging involves diversion of the stream (or other waterbody) around the contaminated
area through the use of coffer dams and diversion conduits, together with physically removing the
contaminated material using a backhoe, clamshell, dragline, front loader, or similar excavation equip-
ment. The possible environmental effects associated with mechanical dredging are summarized in
Table 9.1 and described in the good engineering practice table, Table 9.1a, at the end of this section.
This operation involves construction activities in and adjacent to the waterway outside of the contami-
nated area. The benthic and riparian zones will be disturbed in the areas where construction activities
occur, so the biota inhabiting these zones will be disturbed and could be adversely affected. Disturbing
soils and sediments in the uncontaminated area will lead to turbidity in the waterway. These effects are
inherent to the construction activities and cannot be avoided; however, they are also brief, extending
only over the construction period.
Construction of a coffer dam involving a pile driver, or similar activities, will produce noise. This noise is
also unavoidable, but can be mitigated in part by operating only during normal working hours.
It is probable that the site from which the contaminated sediments will be removed will not be
accessible by road. Construction of access roads will disturb the biota and may require filling in some
wet- and/or low-land areas. If these road accesses are removed and the areas revegetated (see Section
9.4 of EPA 1982) when cleanup activities are completed, the negative effects on the area and inhabiting
biota are temporary and confined only to the cleanup period.
TABLE 9.1. Contaminated Sediments: Mechanical Dredging
Grounu-Water Surface-Water
Movement/ Movement/ Air Soils/
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
Public
Health/ Resource
• NSI
OHSI
N
S
R
NB:
= Highly Probable 3 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
'NSI »HPR — «NSI —
— — • NSI — —
— — 3HPI — —
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
9.1
-------
It may not be desirable or possible to divert the waterway from the contaminated area; alternatively, it
may be possible to conduct the mechanical-dredging operation in-stream. During in-stream mechanical-
dredging operations, contaminated sediments would be resuspended. This might cause a greater
hazard to man and biota than if the sediment were allowed to remain in place. Thus, if the dredging
operation is conducted in-stream, silt curtains (used to contain the majority of the resuspended silt)
would bean integral part of the operation (as described in EPA 1982). However, some sediment would
escape the silt curtains and would present a possible hazard to man and biota. Also, during in-stream
mechanical dredging, sorbed contaminants will desorb into the water and be carried off in solution.
This contamination of the surface water by dissolved contaminants is transitory, confined only to the
period of cleanup, and is unavoidable with in-stream dredging.
In removing the contaminated sediments, spills of sediments and dewatering liquids are to be
expected. These spills will contaminate soils within the site area and should be cleaned up at the close
of site activities.
To remove contaminated sediments, a large volume of material will be moved. This implies a great deal
of traffic related to hauling, and hauling traffic presents a noise and safety hazard to the public. These
adverse effects are unavoidable, but can be mitigated in part by confining traffic to normal daylight
hours and avoiding, to the extent possible, populated areas.
9.2 LOW-TURBIDITY HYDRAULIC DREDGING
Low-turbidity hydraulic dredging involves pumping the sediments from the bottom into barge con-
tainment. Because all of the material removed is contained during the operation, this method reduces
the effects caused by operations. The possible effects that may occur with low-turbidity hydraulic
dredging are summarized in Table 9.2 and described in the good engineering practice table, Table 9.2a,
at the end of this section.
TABLE 9.2. Contaminated Sediments: Low-Turbidity Hydraulic Dredging
Ground-Water
Quality
Movement/
Quantity
Surface-Water
Quality
»HSI
»NSI
Movement/
Quantity
Air
Quality
Soils/
Geology
Biota
• NSI
OHSI
Public
Health/ Resource
Safety Commitments
OHSI —
N
S
R
NB:
= Highly Probable O = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
9.2
-------
Dredging will, however, disturb the habitat of benthic biota. In addition, sorbed contaminants can
desorb into the water and be carried off in a dissolved state. Finally, low-turbidity dredging is not
'no-turbidity' dredging. Some sediments, both contaminated and uncontaminated, will be suspended.
Depending on site-specific conditions, the resuspended sediment that escapes the silt curtains may
present a hazard to man and biota. All of these effects are unavoidable products of the low-turbidity
hydraulic-dredging operation, but are confined to the period of operation and short times thereafter.
9.3 DREDGE-SPOIL MANAGEMENT
Dredge-spoil management consists of activities involved with handling the dredged material after it has
been removed. These activities include the dewatering and transport, storage and disposal, and any
separation or treatment activities that might be conducted to reduce the volume of material to be
disposed of in a secure site. The possible effects that may occur during dredge-spoil management are
summarized in Table 9.3 and described in the good engineering practice tables, Tables 9.3a-c, at the
end of this section.
Dewatering and transport involve reducing the amount of entrained water in the sediment and
transporting the contaminated matter to the ultimate disposal site. Off waters can contain contami-
nated material in suspension or in solution. If the off waters end upon the soil or in surface waters, the
soil or surface water will be contaminated (for instance, if, as described in EPA 1982, a clamshell
operator dewaters the solids by holding these over land or over water before loading onto the truck).
This effect can be mitigated by dedicating an area to off-water containment and treating the waters as
contaminated material. In handling contaminated sediments, spills of the sediments are nearly inevita-
ble. These spills will contaminate the soils where they occur. This effect is mitigated by recognizing the
potential for spills and cleaning these up at the end of site activities. Finally, the transport operation
includes trucking the contaminated sediments off site to a point of ultimate disposal. This involves the
fugitive dust, noise, and safety hazards associated with trucking along the haul route. The noise and
TABLE 9.3. Contaminated Sediments: Dredge-Spoil Management
Dewatering and
Transport
Storage and
Disposal
Separation
Ground-Water
Surface-Water
Public
Health/ Resource
Movement/ Movement/ Air Soils/
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
3 HSR
3NSR
3 HSR
3 HSR
3 HSR
3NSR
>NSI 3HPR — 3NSI
ONSI
1 NPI
• = Highly Probable 3 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
9.3
-------
safety effects are irremediable, but may be mitigated, in part, by conducting trucking activities only
during normal daylight working hours and avoiding, to the extent possible, populated areas. Fugitive
dusts caused by truck hauling are inevitable; release of hazardous matter can be prevented by
containing loads.
Storage and disposal involves temporary or permanent holding of dredge spoils after their removal
from the river bottom. Waters emanating from these spoils will be contaminated and can, in turn,
contaminate ground and/or surface waters. If the spoils are placed for ultimate disposal, contaminants
on the sediments may remobilize and contaminate ground or surface waters. Whether the spoils are
held for storage or for permanent disposal, runoff waters should be collected, monitored, and treated
if contaminated. Because chemical conditions may change after the material has been removed from
the river, monitoring and the option for treatment of runoff waters should continue for an extended
period of time. There is an implied commitment to monitor and treat, if necessary, runoff waters for the
period that the spoils remain hazardous.
Physical or chemical processing of contaminated sediments to reduce the amount of material to be
disposed of in a secure site may be deemed to be cost effective. Physical separation may involve
screening, flotation, and other methods (EPA 1982). Chemical separation may involve the use of
solvents to remove the contaminants. Physical separation using water as a separation medium may
result in contaminated waters if the contaminants dissolve. Chemical treatment can result in emissions
of reagent or solvent material, and spills of contaminated water or solvents can contaminate surface
waters or ground waters. The effects of such spills can be mitigated by recognizing their potential and
planning for their clean up as part of site restoration. Solvent releases to surface or ground waters or
releases of waters used in physical separation should be guarded against and should be contained and
cleaned up at the time of the release.
9.4 REVEGETATION
When the sediments have been removed from wetland environments, it may be deemed necessary to
replace the dredged material and revegetate the area to provide habitat and reduce suspended solids
in the water by stabilizing the soils. The potential effects associated with revegetation are summarized
in Table 9.4 and described in the good engineering practice table, Table 9.4a, at the end of this section.
TABLE 9.4. Contaminated Sediments: Revegetation
Ground-Water Surf ace-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
iNSI — — — (1NPR —
• = Highly Probable 3 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
9.4
-------
The revegetation process may involve bringing in additional soils, introducing or seeding with appro-
priate vegetation, and applying agricultural chemicals (fertilizers and herbicides). Inevitably, bringing
in additional soils, fertilizing, and applying herbicides will introduce suspended solids, nutrients, and
herbicides into the water. These effects are integral to the process, but will disappear when the
revegetation is complete. Bringing in outside soils presents the possibility for introducing species that
do not fit into the local ecosystem; this potential effect is mitigable in part by selecting soils for fill from
similar ecosystems.
9.5
-------
Affected Area
TABLE 9.1a. Contaminated Sediments:/* lechanical Dredging
Effect Mitigation Measure
Surface-Water runoff from disturbed soils can carry sediment none; unavoidable, but temporary if area
Quality to receiving waters revegetated
useof in-stream dredging will result in release silt curtains will minimize but not eliminate
of contaminated suspended sediment and dis- release of contaminated sediment; release of
solved contaminants dissolved contaminants unavoidable but tem-
porary aspect of in-stream dredging
Air Quality haulage activities can result in release of fugi- fugitive-dust control (see Addendum 1); secure
tive dusts loads to prevent releases from trucks
haulage activities will result in noise along haul schedule hauling to minimize effect
route
useof pile driver to build coffer dam will cause none; unavoidable; schedule operation to
noise minimize effect
Soils/Geology spills of sediments and dewatering liquids will use dedicated handling area and clean up at
contaminate handling area end of site activity
Biota biota will be disturbed in area of construction none; unavoidable, but temporary if
activity revegetated
road construction to site, if required, may none; unavoidable, but temporary if accesses
affect wetlands and biota are removed and area revegetated
contaminated suspended sediment or dissolved none; unavoidable, but short-term, aspect of
contaminant may pose risk to biota this technology
Public Health contaminated suspended sediment or dissolved unavoidable, but short-term, aspect of this
or Safety contaminant may pose public health risk technology
haulage activities can present safety hazard plan route and scheduling to minimize hazard
along haul route
9.7
-------
TABLE 9.2a. Contaminated Sediments: Low-Turbidity Hydraulic Dredging
Affected Area Effect Mitigation Measure
Surface-Water dredgingwill result in releaseof smallamount silt curtains will minimize, but not eliminate
Quality of contaminated suspended sediment and dis- release of contaminated sediment; release
solved contaminants of dissolved contaminants unavoidable, but
temporary, aspect of in-stream dredging
Biota biota will be disturbed in area of dredging none; unavoidable aspect of this technology
activity
contaminated suspended sediment or dissolved none; unavoidable, but short-term, aspect of
contaminant may affect biota this technology
Public Health contaminated suspended sediment or dissolved none; unavoidable, but short-term, aspect of
or Safety contaminant may pose public health risk this technology
9.8
-------
TABLE 9.3a. Contaminated Sediments:Dredge-Spoil Management—Dewatering and Transport
Affected Area Effect Mitigation Measure
Surface-Water dredge-spoil off waters may contain dissolved contain off waters and treat as contaminated
Quality or suspended contaminated matter, which can material
contaminate surface waters
Air Quality haulage activities can result in release of fugi- secure loads to prevent releases from trucks
tive dusts along route
haulage activities will result in noise along haul schedule hauling to minimize effect
route
Soils/Geology spills of dewatering liquids will contaminate use dedicated handling area and clean up at
handling area end of site activity
Public Health haulage activities can present safety hazard plan route and scheduling to avoid hazard
or Safety along haul route
9.9
-------
TABLE 9.3b. Contaminated Sediments:Dredge-Spoil Management—Storage and Disposal
Affected Area Effect Mitigation Measure
Ground-Water dredge-spoil runoff may contain dissolved contain runoff, monitor, and treat if required
Quality contaminants, which can contaminate ground
water
Surface-Water dredge-spoil runoff may contain dissolved or contain runoff, monitor, and treat if required
Quality suspended contaminated matter which can
contaminate surface waters
Resource storage or disposal of dredge spoils implies none; unavoidable effect of this option
Commitment commitment to monitor and treat runoff
waters, if necessary, over the period that the
spoils remain hazardous
9.10
-------
TABLE 9.3c. Contaminated Sediments:Dredge-Spoil Management—Separation
Affected Area Effect Mitigation Measure
Ground-Water dredge-spoil processing waters may contain contain process waters, monitor, and treat as
Quality dissolved contaminants which can contami- required
nate ground water
spills of processing reagents may contaminate plan for spills; clean up at time of spill
ground water
separation agents can reduce air quality
none; unavoidable effect of this option
Surface-Water dredge-spoil process waters may contain dis- contain process water and treat as contami-
Quality solved or suspended contaminated matter, nated material
which can contaminate surface waters
spills of processing reagents may contaminate plan for spills; clean up at time of spill
surface waters
9.11
-------
TABLE 9.4a. Contaminated Sediments:Revegetation
Affected Area Effect Mitigation Measure
Surface-Water revegetating wetlands by bringing in soil and none; irremediable, but temporary aspect of
Quality fertilizing, and applying herbicides will intro- this action
duce suspended solids, nutrients, and herbi-
cides into surface waters
Biota use of outside soil can introduce new and use soil from similar ecosystems
inappropriate species
9.12
-------
10.0 REFERENCES
Beedlow, P. A. 1984. Designing Vegetation Covers for Long-Term Stabilization of Uranium Mill Tailings.
NUREG/CR-3674 (PNL-4986), Nuclear Regulatory Commission, Washington, D.C.
EPA. 1982. Handbook for Remedial Action at Waste Disposal Sites. EPA-625/6-82-006, U.S. Environmental Protec-
tion Agency, Office of Research and Development, Cincinnati, Ohio.
Shafer, J. M., P. L. Oberlander and R. L. Skaggs. 1984. Mitigation Techniques and Analysis of Generic Site
Conditions for Ground-Water Contamination Associated with Severe Accidents. NUREG/CR-3681 (PNL-5072),
Nuclear Regulatory Commission, Washington, D.C.
10.1
-------
APPENDIX A
MONITORING SYSTEMS
-------
APPENDIX A
MONITORING SYSTEMS
Monitoring systems provide in formation on the effectiveness of the remedial action and provide early
warning of breakdown of the remedy. These systems monitor ground-water, surface-water, and
atmospheric releases. The potential effects of ground-water monitoring are summarized in Table A.I
and described in the good engineering practice table, Table A.1a, at the end of this section.
A.I GROUND-WATER MONITORING
Ground-water monitoring involves installing wells into one or more aquifers and a continuing sam-
pling program. The construction of the well presents the major potential for negative effects. Well
cuttings and waters withdrawn during completion and sampling are very likely contaminated. If
cuttings are allowed to fall where they may, additional soils may be contaminated. If water pumped
during well completion is discharged to the surface, soil and surface-water contamination may result.
These effects can be remedied by handling all material removed from the ground as contaminated
matter to be disposed of properly.
Also, if several aquifers are beirtg monitored, the well can potentially cause cross-aquifer contamina-
tion. This can be prevented by proper grouting and completion of the well (EPA 1982).
Drilling operations are noisy and may be a source of complaint. This can be mitigated in part by
operating the drill rig only during normal daylight working hours.
The sampling program will disturb local biota during those periods when people and equipment are in
the area. This is a temporary, but irremediable, aspect of the sampling program. If breeding habitat for
sensitive species are nearby, disturbance can be mitigated by appropriate timing of sampling activities.
TABLE A.1. Monitoring Systems
Ground-Water Surface-Water
Movement/ Movement/
Quality Quantity Quality Quantity
Ground-Water
Monitoring OHPR — 3 HPR —
Surface-Water
Monitoring — — — —
Gas
Monitoring — •— — —
Public
Air Soils/ Health/ Resource
Quality Geology Biota Safety Commitments
<1NSI
-------
A.2 SURFACE-WATER MONITORING
No significant effects are projected.
A.3 GAS MONITORING
No significant effects are projected.
REFERENCE
EPA. 1982. Ground-Water Monitoring Guidance for Owners and Operators of Interim Status Facilities:
Instructions for Complying with 40 CFR Part 265, Subpart F. U. S. Environmental Protection Agency,
Washington, D. C.
A.2
-------
TABLE A.1a. Monitoring Systems: Ground-Water Monitoring
Affected Area Effect Mitigation Measure
Ground-Water cross-aquifer contamination can result from establish and enforce procedures for well
Quality multiple aquifer wells logging, grouting, and completion
Surface-Water water pumped during well completion can treat development waters as contaminated
Quality contaminate receiving waters matter
Air Quality drilling will produce noise schedule drilling operations to reduce effect
Soils/Geology drill cuttings or development waters may con- treat all materials removed from the ground as
laminate soil contaminated matter
Biota sampling activities will disrupt wildlife none; unavoidable; if sensitive, schedule
sampling to reduce effect
A.3
-------
APPENDIX B
WASTE-WATER TREATMENT MODULES
-------
APPENDIX B
WASTE-WATER TREATMENT MODULES
Leachate may be treated using industrial waste-water treatment methods. The potential effects of these
various treatment methods are described below. Note that these methods are not necessarily alterna-
tives to each other. Instead, several may be used in concert to make up a treatment strategy alternative.
B.1 FLOW EQUALIZATION
Flow equalization basins act to dampen flow and concentration fluctuations in the treatment stream.
Potential effects of this treatment option are summarized in Table B.I and described in the good
engineering practice table, Table B.1 a, at the end of this section.
If the flow equalization basin is open to the atmosphere, hazardous materials may evaporate and
degrade air quality. This effect may be remedied by covering the basin.
Construction of the equalization basin may result in construction-related effects. These effects include
the emission of fugitive dusts, which can be reduced by water spray and other control means (see
Addendum 1). Construction activities will also disturb soils; overland flow can then transport these
disturbed soils as suspended solids to receiving waters. This effect can be mitigated by using surface-
water diversion and collection controls (see Section 3.4 of EPA 1982) while the basin is being con-
structed and revegetating (see Section 3.3 of EPA 1982) after construction activities are completed.
Ground-Water
TABLE B.1. Waste-Water Treatment: Flow Equalization
Surface-Water
Movement/
Quality Quantity Quality
Public
Movement/ Air Soils/ Health/ Resource
Quantity Quality Geology Biota Safety Commitments
(1NSR
• NSR
» HSR
— ONSR
N
S
R
NB:
= Highly Probable O = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
B.2 PRECIPITATION, FLOCCULATION, AND SEDIMENTATION
Precipitation, flocculation, and sedimentation are waste-water treatment processes that are used
widely to treat industrial waste waters containing particulates and/or heavy metals. Each of these
processes produces by-products that must be properly disposed of. Failure to dispose of these
by-products properly can result in ground-water, surface-water, air, and soil contamination, which can
result in adverse effects to the public and biota residing near the disposal site. Proper disposal means
treating the by-products as hazardous matter and disposing of these in a RCRA-approved site. Potential
effects of this treatment option are summarized in Table B.2 and described in the good engineering
practice table, Table B.2a, at the end of this section.
B.1
-------
TABLE B.2. Waste-Water Treatment: Precipitation, Flocculation and Sedimentation
Ground-Water Surf ace-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
OHPR
ONSR
OHPR
• NSR
OHPR
3HPR
« NSR a HPR
3HPR —
• = Highly Probable 9 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
Each of the processes uses reagents; spills of these reagents and/or runoff from reagent storage may
contaminate surface waters. Spills of the reagents, although not inevitable, are probable, so cleanup
and disposal plans should be part of the operating plan. Reagent storage areas should be designed so
that runoff from these is collected and diverted to the treatment facility.
Construction of the precipitation, flocculation, and sedimentation facilities may result in construction-
related effects. These effects include the emission of fugitive dusts, which can be reduced by water
spraying and other control techniques (see Addendum 1). Construction activities will also disturb soils,
which can carry suspended solids to receiving waters by overland flow. This effect can be mitigated by
using surface-water diversion and collection controls (see Section 3.4 of EPA 1982) while the basin is
being constructed and revegetating (see Section 3.3 of EPA 1982) after construction activities are
completed. If not prevented, these fugitive dusts and sediment releases can affect resident biota.
B.3 BIOTREATMENT
Most organic chemicals are biodegradable and a large number of biotreatment options are available.
All of these produce a by-product that must be disposed of properly, although the by-product will
probably be much less hazardous than the original material. Failure to dispose of these by-products
properly can result in ground-water, surface-water, air, and soil contamination, which can result in
adverse affects on the public and biota residing near the disposal site. Proper disposal means treating
the by-products as hazardous matter and disposing of these in a RCRA-approved site. Potential effects
of this treatment option are summarized in Table B.3 and described in the good engineering practice
table, Table B.3a, at the end of this section.
Construction of biotreatment facilities may cause adverse effects such as the emission of fugitive dusts.
Construction activities will also disturb soils, which can carry suspended solids to receiving waters by
overland flow. This effect can be mitigated by using surface-water diversion and collection controls
(see Section 3.4 of EPA 1982) while the basin is being constructed and revegetating (see Section 3.3 of
EPA 1982) after construction activities are completed. Fugitive dusts can be reduced by water spraying
and other control techniques (see Addendum 1). If not prevented, these fugutive dusts and sediment
releases can affect resident biota.
B.2
-------
TABLE B.3. Waste-Water Treatment: Biotreatment
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
All
Biotreatment
Methods 3HPR — fJNSR — OHPR OHPR »HPR OHPR »NSI
— — »HPR — »NSR — — — —
— — — — 3NSI — — — —
Activated
Sludge — — — — — — — — »NSI
Trickling
Filters — — — — — — — — • NSI
Rotating
Biological Disks — — — — — — — — • NSI
Bioseeding — — — — - — — »NSR —
Anaerobic,
Aerobic, and
Faculative
Lagoons — — — — — — — — —
• = Highly Probable O = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
Biotreatment processes may release noxious or offensive odors that may degrade air quality. This
problem is common to the processes and is not specifically mitigable. Activated sludge, trickling filter,
and rotating biological disk processes require a commitment of energy for pumping or for rotating the
disks. This resource commitment is integral to these biotreatment processes and is not mitigable.
Bioseeding, that is the introduction of specifically adapted microorganisms to any of the biotreatment
options, can potentially be perceived by the public as a health and safety risk associated with exotic
microorganisms. Although this effect is perceptual rather than actual, it could affect the operation of
the treatment facility if public opposition is aroused. This can be avoided by educating the public.
B.4 CARBON SORPTION
Carbon sorption can be used in a treatment mode for dilute leachate or in a polishing mode. Aside
from disposal of spent carbon or waste material obtained during regeneration of the carbon, no
significant effects are associated with the use of carbon sorption as a treatment option. Failure to
dispose of these by-products properly can result in ground-water, surface-water, air, and soil contami-
nation, which can result in adverse affects on the public and biota residing near the disposal site. Proper
disposal means treating the by-products as hazardous matter and disposing of these in a RCRA-
approved site. Table B.4 has no entries except those related to by-product disposal. Table B.4a, at the
end of this section describes the good engineering practices for by-product disposal.
B.3
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TABLE B.4. Waste-Water Treatment: Carbon Sorption
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
3HPR
3HPR »HPR OHPR OHPR
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
B.5 ION EXCHANGE
Ion-exchange resins can be used, in the same way as carbon, to sorb specific hazardous materials in a
polishing mode or a direct treatment mode for very dilute leachates. Again, no significant adverse
effects other than those related to disposal of resins and by-products are associated with this process.
Failure to dispose of these by-products properly can result in ground-water, surface-water, air, and soil
contamination, which can result in adverse effects to the public and biota residing near the disposal
site. Proper disposal means treating the by-products as hazardous matter and disposing of these in a
RCRA-approved site. Table B.5 has no entries except those related to by-product disposal and Table
B.5a at the end of the section describes good engineering practices for by-product disposal.
TABLE B.5. Waste-Water Treatment: Ion Exchange
Ground-Water
Quality
OHPR
Movement/
Quantity
Surf ace-Water
Quality
(1HPR
Movement/
Quantity
Air
Quality
(1HPR
Soils/
Geology
Biota
Public
Health/ Resource
Safety Commitments
— »HPR OHPR
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
B.6 LIQUID ION EXCHANGE
Liquid ion exchange involves selectively removing contaminants from the leachate by dissolution in an
immiscible organic material. Potential effects of this treatment option are summarized in Table B.6 and
described in the good engineering practice table, Table B.6a, at the end of this section.
The immiscible organic material is at least partially soluble in the aqueous stream, and releases of the
solvent to the stream must either be tolerated or the stream must undergo further treatment to remove
B.4
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TABLE B.6. Waste-Water Treatment: Liquid Ion Exchange
Ground-Water
Movement/
Quality Quantity Quality
0>HPR
Surface-Water Public
Movement/ Air Soils/ Health/ Resource
Quantity Quality Geology Biota Safety Commitments
G>HPR
»NSR
(JHPR 3HPR
3HPR3HPR
— »NSR
N
S
R
NB:
= Highly Probable 3 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
= Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
traces of the solvent. In addition, spills of the solvent may contaminate surface waters if not contained.
The solvents themselves can represent a health or safety hazard to personnel working at the site or to
the public. Many of the solvents are flammable and some are toxic. If a fire or explosion occurs at the
facility, the hazardous material could be spread over a greater area than was originally contaminated.
Although this possibility is remote, it must be considered. Proper safety planning and precautions can
reduce the probability of such accidents.
The ion-exchange process produces by-products which must be disposed of properly. Failure to
dispose of these by-products properly can result in ground-water, surface-water, air, and soil contami-
nation, which can result in adverse effects to the public and biota residing near the disposal site. Proper
disposal means treating the by-products as hazardous matter and disposing of these in a RCRA-
approved site.
B.7 AMMONIA STRIPPING
Ammonia stripping is a process wherein ammonia in the waste stream is sparged with air. Potential
effects of this treatment option are summarized in Table B.7 and described in the good engineering
practice table. Table B.7a, at the end of this section.
Ground-Water
TABLE B.7. Waste-Water Treatment: Ammonia Stripping
Surface-Water
Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
ONSR
OHSR
• = Highly Probable (9 = Probable O = Improbable
N = Nuisance H = Hazardous — = No significant effects predicted
S = Short-term (construction phase only) P = Persistent (beyond construction phase)
R = Reversible (or mitigable) I = Irreversible (unmitigable)
NB: Multiple entries in a category indicate that several different types of effects are foreseen as possible.
B.5
-------
If open to the atmosphere, this stripping process will release ammonia to the air, which may degrade air
quality in the vicinity of the treatment site. If the air quality would be degraded significantly, the
ammonia should be collected in a sorption unit. Hazardous volatile compounds may also be sparged
with the ammonia. This effect is unavoidable with the use of this technology.
B.8 WET-AIR OXIDATION
No significant adverse effects other than those associated with improper disposal of by-products were
found to be associated with wet-air oxidation. Table B.8 has no entries except those related to
by-product disposal, and good engineering practices for by-product disposal are described in Table
B.8a, at the end of this section.
Failure to dispose of these by-products properly can result in ground-water, surface-water, air, and soil
contamination, which can result in adverse effects to the public and biota residing near the disposal
site. Proper disposal means treating the by-products as hazardous matter and disposing of these in a
RCRA-approved site.
TABLE B.8. Waste-Water Treatment: Wet-Air Oxidation
Surf ace-Water
Ground-Water Surface-Water Public
Movement/ Movement/ Air Soils/ Health/ Resource
Quality Quantity Quality Quantity Quality Geology Biota Safety Commitments
OHPR
3HPR
dHPR 3HPR OHPR »HPR
N
S
R
NB:
= Highly Probable 9 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
= Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
B.9 CHLORINATION
Chlorination is a process used in waste-water treatment to disinfect, to control odor, and to reduce
biological oxygen demand. Potential effects of this treatment option are summarized in Table B.9 and
described in the good engineering practice table, Table B.9a, at the end of this section.
Chlorination involves introducing gaseous chlorine into the waste-water stream. The presence of
gaseous chlorine on site introduces the possibility of atmospheric releases of chlorine with attendant
air-quality degradation and, in the case of a significant accident, a hazard to human health and safety.
This effect is an irremediable, but improbable, component of the use of gaseous chlorine.
Chlorination can reduce the biological oxygen demand. However, depending on the chemical
constituents in the waste stream, chlorination can turn relatively benign contaminants into more
hazardous contaminants (for instance, chlorination can convert phenols into polychlorinated
B.6
-------
Ground-Water
TABLE B.9. Waste-Water Treatment: Chlorination
Surface-Water
Quality
Movement/
Quantity
Quality
(»HSI
Movement/ Air
Quantity Quality
Soils/
Geology Biota
Public
Health/ Resource
Safety Commitments
ONSI
N
S
R
NB:
= Highly Probable 3 = Probable
= Nuisance H = Hazardous
= Short-term (construction phase only)
= Reversible (or mitigable)
'NSR OHSI
O = Improbable
— = No significant effects predicted
P = Persistent (beyond construction phase)
I = Irreversible (unmitigable)
Multiple entries in a category indicate that several different types of effects are foreseen as possible.
phenols). Toxic contaminants may adversely affect human health and that of biota residing in the
receiving streams. This effect is an integral and unmitigable aspect of the use of Chlorination in
waste-water treatment and should be considered when considering the Chlorination option. Also, if
the waste-water stream is released with free chlorine remaining in the stream, this chlorine will be toxic
to biota in the receiving waters. This effect can be mitigated by the use of a dechlorination facility. The
effects of chlorination of waste stream are discussed in numerous references; some of these are Bean,
Riley, and Ryan (1978); Jolley et al. (1980); Jolley et al. (1983a); Jolley et al. (1983b); and Bean, Neitzel,and
Thomas (1984).
REFERENCES
Bean, R. M., R. G. Riley and P. W. Ryan. 1978. "Investigation of Halogenated Components Formed from Chlorina-
tion of Marine Water." In Wafer Chlorination Environmental Impact and Health Effects, Volume 2, pp 223-333, Ann
Arbor Science Publishers, Inc., Ann Arbor, Michigan.
Bean, R. M., D. A. Neitzel and B. L. Thomas. 1984. "Analysis of Sediment and Suspended Matter for Halogenated
Products from Chlorination of Power Plant Cooling Matter." Paper presented at the Fifth Conference on Water
Chlorination: Environmental Impact and Health Effects, June 3-8,1984, Williamsburg, Virginia.
EPA. 1982. Handbook for Remedial Action at Waste Disposal Sites. EPA-625/6-82-006, U.S. Environmental Protec-
tion Agency, Office of Research and Development, Cincinnati, Ohio.
Jolley, R. L., W. A. Brungs, R. B. Gumming and V. A. Jacobs, eds. 1980. Water Chlorination, Environmental Impact
and Health Effects, Volume 3. Ann Arbor Science Publishers, Inc., Ann Arbor, Michigan.
Jolley, R. L., W. A. Brungs, J. A. Cotruvo, R. B. Cumming, J. S. Mattice and V. A. Jacobs, eds. 1983a. Water
Chlorination, Environmental Impact and Health Effects, Volume 4, Book 7, Chemistry and Water Treatment. Ann
Arbor Science Publishers, Inc, Ann Arbor, Michigan.
Jolley, R. L., W. A. Brungs, J. A. Cotruvo, R. B. Cumming, J. S. Mattice and V. A. Jacobs, eds. 1983b. Water
Chlorination, Environmental Impact and Health Effects, Volume 4, Book 2, Environment, Health, and Risk. Ann
Arbor Science Publishers, Inc., Ann Arbor, Michigan.
B.7
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Affected Area
TABLE B.la. Waste-Water Treatment Modules: Flow Equalization
Effect
Mitigation Measure
Surface-Water runoff from soils disturbed during construe- incorporate surface-water diversion and coi-
tion activities can carry sediment to receiving lection measures with revegetation as appro-
waters rriate (see EPA 1982, Sections 3.3 and 3.4)
Quality
Air Quality
Biota
construction activities can result in release of fugitive-dust control (see Addendum 1)
fugitive dusts
evaporation of hazardous matter may contam- cover basin
inate air
fugitive dust from excavation can affect nearby see air quality above
biota
sediment from excavation can affect aquatic see surface-water quality above
biota
B.9
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TABLE B.2a. Waste-Water Treatment Modules:Precipitation, Flocculation, and Sedimentation
Affected Area
Effect
Mitigation Measure
Ground-Water improper disposal of by-product matter can
Quality cause ground-water contamination
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
reagent spills can contaminate receiving
waters
runoff from reagent storage can contaminate
receiving waters
improper disposal of by-product matter can
contaminate surface waters
Air Quality construction activities can result in release of
fugitive dusts
improper disposal of by-product matter can
cause air contamination
Soils/Geology improper disposal of by-product matter can
cause soil contamination
Biota fugitive dust from construction can affect
nearby biota
sediment from construction can affect aquatic
biota
improper disposal of by-product matter can
affect biota at disposal site
Public Health improper disposal of by-products can affect
or Safety public health for persons near disposal site
see surface-water quality below
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
incorporate cleanup and disposal of reagent
spills as part of operating plan
collect runoff and divert to treatment area
treat by-products as contaminated matter;
dispose of in a RCRA-approved site
fugitive-dust control (see Addendum 1)
see surface-water quality above
see surface-water quality above
see air quality above
see surface-water quality above
see surface-water quality above
see surface-water quality above
B.10
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TABLE B.3a. Waste-Water Treatment Modules: Biotreatment
Affected Area
Effect
Ground-Water improper disposal of by-product matter can
Quality cause ground-water contamination
Surface-Water runoff from soils disturbed during construc-
Quality tion activities can carry sediment to receiving
waters
improper disposal of by-product matter can
contaminate surface waters
Air Quality construction activities can result in release of
fugitive dusts
biotreatment of some materials may release
noxious or offensive odors
improper disposal of by-product matter can
cause air contamination
Soils/Geology improper disposal of by-product matter can
cause soil contamination
Biota fugitive dust from construction can affect
nearby biota
sediment from construction can affect aquatic
biota
improper disposal of by-product matter can
affect biota at disposal site
Public Health improper disposal of by-products can affect
or Safety public health of persons near disposal site
introduction of microorganisms can be per-
ceived as health risk
resource commitment
Mitigation Measure
see surface-water quality below
incorporate surface-water diversion and col-
lection measures with revegetation as appro-
priate (see EPA 1982, Sections 3.3 and 3.4)
treat by-products as contaminated matter;
dispose of in a RCRA-approved site
fugitive-dust control (see Addendum 1)
none; unavoidable effect of this technology
see surface-water quality above
see surface-water quality above
see air quality above
see surface-water quality above
see surface-water quality above
see surface-water quality above
education of public
unavoidable; some processes require energy
for operation; this is an integral part of these
technologies
B.11
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TABLE B.4a. Waste-Water Treatment Modules: Carbon Sorption
Affected Area
Effect
Mitigation Measure
Ground-Water improper disposal of by-product matter can
Quality cause ground-water contamination
Surface-Water improper disposal of by-product matter can
Quality contaminate surface waters
Air Quality improper disposal of by-product matter can
cause air contamination
Soils/Geology improper disposal of by-product matter can
cause soil contamination
Biota improper disposal of by-product matter can
affect biota at disposal site
Public Health improper disposal of by-products can affect
or Safety public health of persons near disposal site
see surface-water quality below
treat by-products as contaminated matter;
dispose of in a RCRA-approved site
see surface-water quality above
see surface-water quality above
see surface-water quality above
see surface-water quality above
B.12
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TABLE B.5a. Waste-Water Treatment Modules: Ion Exchange
Affected Area Effect Mitigation Measure
Ground-Water improper disposal of resins and by-product see surface-water quality below
Quality matter can cause ground-water contamination
Surface-Water improper disposal of resins and by-product treat by-products as contaminated matter;
Quality matter can contaminate surface waters dispose of in a RCRA-approved site
Air Quality improper disposal of resins and by-product see surface-water quality above
matter an cause air contamination
Soils/Geology improper disposal of resins and by-product see surface-water quality above
matter can cause soil contamination
Biota improper disposal of resins and by-product see surface-water quality above
matter can affect biota at disposal site
B.13
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TABLE B.6a. Waste-Water Treatment Modules: Liquid Ion Exchange
Affected Area
Effect
Ground-Water improper disposal of by-product matter can
Quality cause ground-water contamination
Surface-Water improper disposal of by-product matter can
Quality contaminate surface waters
spills of ion-exchange liquid can contaminate
receiving waters
ion-exchange liquid in waste stream can con-
taminate receiving waters
Air Quality improper disposal of by-product matter can
cause air contamination
Soils/Geology improper disposal of by-product matter can
cause soil contamination
Biota improper disposal of by-product matter can
affect biota at disposal site
Public Health personnel may be exposed to flammable or
or Safety toxic vapors from ion-exchange liquid
fire or explosion of ion-exchange material
could cause greater public exposure than cur-
rent situation
improper disposal of by-product matter can
affect public health near disposal site
Mitigation Measure
see surface-water quality below
treat by-products as contaminated matter;
dispose of in a RCRA-approved site
plan for containing spills
none; unavoidable; treat waste stream to
remove ion-exchange traces if needed
see surface-water quality above
see surface-water quality above
see surface-water quality above
proper safety planning and precautions
proper safety planning and precautions
see surface-water quality above
B.14
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TABLE B.7a. Waste-Water Treatment Modules: Ammonia Stripping
Affected Area Effect Mitigation Measure
Air Quality released ammonia may degrade local air collect ammonia in a sorption unit
quality
volatile hazardous materials may be sparged none; unavoidable aspect
with the ammonia
B.15
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TABLE B.8a. Waste-Water Treatment Modules: Wet-Air Oxidation
Affected Area
Effect
Ground-Water improper disposal of by-product matter (if
Quality any) can cause ground-water contamination
Surface-Water improper disposal of by-product matter (if
Quality any) can contaminate surface waters
Air Quality improper disposal of by-product matter (if
any) can cause air contamination
Soils/Geology improper disposal of by-product matter (if
any) can cause soil contamination
Biota
improper disposal of by-product matter (if
any) can affect biota at disposal site
Public Health improper disposal of by-products can affect
or Safety public health for persons near disposal site
Mitigation Measure
see surface-water quality below
treat by-products as contaminated matter;
dispose of in a RCRA-approved site
see surface-water quality above
see surface-water quality above
see surface-water quality above
see surface-water quality above
B.16
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TABLE B.9a. Waste-Water Treatment Modules: Chlorination
Affected Area Effect Mitigation Measure
Air Quality leaks or accidental releases of chlorine can establish and enforce appropriate safety
degrade local air quality procedures
Biota chlorination by-products may be toxic to biota perform tests to determine chlorination
products
free chlorine in waste stream will be toxic to use a dechlorination facility
biota
Public Health some chlorination by-products may be more perform tests to determine chlorination
or Safety toxic than those in waste stream products
B.17
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ADDENDUM 1
FUGITIVE DUST
-------
ADDENDUM 1
FUGITIVE DUST
Fugitive-dust emissions are defined as any paniculate emissions to the atmosphere that are not
released through a stack, vent, duct, or other exhaust system designed to regulate the flow of the
pollutants. Fugitive-dust emissions will occur as the result of wind erosion and/or construction
activities (e.g., vehicular traffic, digging, blasting, etc.). The amount of material released to the
atmosphere by wind erosion will depend on ambient wind speeds, atmospheric turbulence and
stability, and the physical characteristics of the material itself (particle size, particle density, particle
shape) (Chepil 1951; Bagnold 1954). Mechanically generated fugitive-dust emissions will depend on
the type of construction activities (equipment, vehicle miles, etc.) and the physical properties of the
surface material (Bohn et al. 1978). Potential amounts of fugitive-dust emissions and subsequent air
concentrations can be estimated, if necessary, using established emission-factor guidelines and air-
quality models (see e.g., Blackwood and Wachter 1978; Bohn et al. 1978; EPA 1979; EPA 1977). Such
steps may be necessary if potential emission would result in a violation of the applicable total
suspended particulate (TSP) and ambient air-quality standards. Likewise, it may be desirable or neces-
sary to estimate fugitive-emission rates, air concentration, and deposition patterns if the material in
question is deemed hazardous.
Several control strategies are available to regulate fugitive-dust emissions. These include treating the
exposed surface to reduce dust emissions, or erecting wind barriers to reduce wind speeds and hence
emission rates (Li et al. 1983). Treatment technologies include covering the surface with materials such
as straw, bark, or rock; applying a water spray; and applying a chemical dust-suppressant compound.
Covers are appropriate only if the material will not be further disturbed during construction activities.
Water spray is only about 50% effective in reducing dust emissions and is a temporary measure only,
requiring repeated application (PEDCo 1973). Numerous chemical treatments are available commer-
cially and are very effective in controlling dust emissions (85% reduction and higher) (PEDCo 1973;
Elmone and Hartley 1984). Their durability and effectiveness depends on the material being treated and
subsequent construction activities which may erode the agents applied to the surface.
Wind barriers have been proven to regulate fugitive emissions effectively. They range from simple
fencing (e.g., snow fencing) to more elaborate panels that are specifically designed to control fugitive
emissions (Radkey and MacCready 1979; Li et al. 1983). Some commercial units are portable so they can
be adjusted to particular wind directions or moved from site to site. Their effectiveness depends on
their height and width, their 'porosity' to the ambient wind, and their positioning relative to the area to
be protected. Wind barriers can also be constructed from materials removed during excavation and
construction activities. If a sufficient amount of material must be temporarily removed and stored, it
can be placed in a mound upwind of the areas likely to be subject to fugitive emissions. With proper
placement and construction, such barriers can reduce wind speed below threshold levels at which
wind erosion occurs. Davies (1980) reports on a physical modeling study of such a control strategy.
Costs for fugitive-dust control are summarized in Table AD.1.
Construction-related dust emissions can be reduced by using a combination of the above mitigating
measures, and regulating vehicle speeds (PEDCo 1973). Meteorological conditions conducive to
intense dust emission and transport episodes can be monitored either on site or via a local weather
office. Construction activities can then be controlled appropriately to reduce emissions during unfa-
vorable atmospheric conditions.
AD-1.1
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TABLE AD.1 Fugitive-Dust Control Costs
Unpaved Roads
Exposed Areas
$2-5/acre/day(f)
Construction Site
Storage Pile
for spray system
$10,000-11,000 est.
for permanent system'6)
Water Spray'3)
$3000/mile AOC(dMe)
$4-10/acre AOddMe)
$300/hectare<8)
$2-5/acre/day(f)
Chemical
Stabilizers^)
$5000-12,000/mile AOC(e)
$35-50/acre
AOC
(a) Effectiveness of water spray depends on environmental factors and
regularity of watering; costs will vary accordingly.
(b)Costs for chemical stabilization vary with compound used; research
results indicate that less effective compounds require more frequent
application, hence costs ranges may be narrower than reported.
(c) Limited data available on wind break costs; reported values are for tree
liners and several commercial systems only.
(d)Annual operating costs; does not include initial costs for equipment
purchase (e.g., spray trucks).
(e)Bohnetal. (1978).
(f) PEDCo (1973).
(g)Elmone and Hartley (1984).
REFERENCES
Bagnold, R. A. 1954. The Physics of Blown Sand and Desert Dunes. Methuen and Co., Ltd., London, England.
Blackwood, T. R., and R. A. Wachter. 1978. Source Assessment: Coal Storage Piles. EPA-600/2-78-004R, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina.
Bohn, R., T. Cuscino and C. Cowherd. 1978. Fugitive Emissions from Integrated Iron and Steel Plants. EPA-600/2-78-
050, U.S. Environmental Protection Agency, Research Triangle Park, N.C.
Chepil, W. S. 1951. "Properties of Soil Which Influence Wind Erosion." Soil Science 72:465-478.
Davies, A. E. 1980. "A Physical Modeling Approach to the Solution of Fugitive Emission Problems." In Proceedings
73rd Annual Meeting of the Air Pollution Control Association, Montreal, Quebec, June 22-27,1980.
Elmone, M. R., and J. N. Hartley. 1984. Laboratory Testing of Chemical Stabilizers for Control of Fugitive Dust
Emissions from Uranium Mill Tailings. NUREG/CR-3697, U.S. Nuclear Regulatory Commission, Washington, D.C.
Li, C. T., M. R. Elmone and J. N. Hartley. 1983. A Review of Fugitive Dust Control for Uranium Mill Tailings.
NUREG/CR-2856, U.S. Nuclear Regulatory Commission, Washington, D.C.
PEDCo. 1973. Investigation of Fugitive Dust - Sources, Emissions and Control. PEDCo Environmental Specialists,
Inc., Cincinnati, Ohio.
AD-1.2
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Radkey, R. L, and P. B. MacCready. 1979. A Study of the Use of Porous Wind Fences to Reduce Paniculate
Emissions at a Coal-Fired Generating Station. AVTP-951212, Environment, Inc., Pasadena, California.
U.S. Environmental Protection Agency. 1977. Compilation of Air Pollutant Emission Factors, Third Edition (Includ-
ing Supplements). AP-42, Office of Air and Waste Management, Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina.
U.S. Environmental Protection Agency. 1979. Industrial Source Counter (ISC) Dispersion Model User's Guide,
Volume I and II. EPA 450/4-79-030, Research Triangle Park, North Carolina.
AD-1.3
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ADDENDUM 2
OTHER AIRBORNE EMISSIONS
-------
ADDENDUM 2
OTHER AIRBORNE EMISSIONS
Before implementing the remedial activities, the potential impacts resulting from release to the
atmosphere of noxious or hazardous materials can be evaluated using established procedure. Gases,
aerosols, or particles may be emitted as a result of routine operations or because of an assistant (fire,
explosion, etc.). The subsequent transport and diffusion of these materials will result in downwind
concentrations, either on site or off site, that may adversely affect environmental quality or public
welfare. After evaluating the potential sources of such emissions and their likelihood of occurrence,
air-quality dispersion modeling techniques can be used to estimate the locations and magnitude of
maximum impacts (Turner 1967; Hanna et al. 1982; Ramsdell and Athey 1981). Meteorological data for
these studies can be provided through an on-site monitoring program or from historical observations
collected at nearby weather stations. The results of these evaluations can be used to estimate maximum
impacts and provide guidelines for construction-related activities to help minimize emissions, particu-
larly during periods of unfavorable atmospheric conditions.
REFERENCES
Hanna, S. R., C. A. Briggs and R. P. Hosker. 1982. Handbook on Atmospheric Diffusion. DOE/TIC-11223, U.S.
Department of Energy, Washington, D.C.
Ramsdell, J. V., and G. F. Athey. 1981. MESOI: An Interactive Lagrangian Trajectory Puff Diffusion Model.
PNL-3968, Pacific Northwest Laboratory, Richland, Washington.
Turner, D.B. 1967. Workbook of Atmospheric Dispersion Estimates. Public Health Service, Publication 999-AP-26,
Robert A. Toff Sanitary Engineering Center, Cincinnati, Ohio.
AD-2.1
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