Biological Services Program
FWS/OBS-81/05
AUGUST 1981
Coal Combustion Waste Manual:
Evaluating Impacts to Fish and Wildlife
Office of Research and Development
U.S. Environmental Protection Agency
Fish and Wildlife Service
U.S. Department of the Interior
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The Biological Services Program was established within the U.S. Fish and
Wildlife Service to supply scientific information and methodologies on key
environmental issues that impact fish and wildlife resources and their supporting
ecosystems.
Projects have been initiated in the following areas: coal extraction and
conversion; power plants; mineral development; water resource analysis, including
stream alterations and western water allocation; coastal ecosystems and Outer
Continental' Shelf development; environmental contaminants; National Wetland
Inventory; habitat classification and evaluation; inventory and data management
systems; and information management.
The Biological Services Program consists of the Office of Biological Services in
Washington, D.C., which is responsible for overall planning and management;
National Teams, which provide the Program's central scientific and technical
expertise and arrange for development of information and technology by contracting
with States, universities, consulting firms, and others; Regional Teams, which
provide local expertise and are an important link between the National Teams and
the problems at the operating level; and staff at certain Fish and Wildlife Service
research facilities, who conduct inhouse research studies.
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UN!TED STATES
DEPARTMENT OF THE INTERIOR
FISH AND WILDLIFE SERVICE
EASTERN ENERGY AND LAND USE TEAM
Route 3, Box 44
Keameysville, West Virginia 25430
Dear Colleague:
The Eastern Energy and Land Use Team, Office of Biological Services,
is pleased to provide you with a copy of the enclosed publication.
This report is intended to assist the biologist, planner, manager,
and public in making decisions affecting the Nation's fish and wild-
life resources.
The goal of this manual is to provide quantitative guidelines, where
possible, for evaluating the potential extent of habitat disturbances
from waste constitutent dispersal. Criteria are also provided for
evaluating the potential for impact from trace elements in the waste.
This manual is designed to be used in conjunction with the technical
report entitled "Handling of Combustion and Emission-Abatement Wastes
from Coal-Fired Power Plants: Implications for Fish and Wildlife
Resources" (FWS/0BS-80/33 9/30/81).
We are interested in your thoughts and comments concerning this
publication and the kinds of information materials you would like
to see the Team produce in the future. We invite you to write us
at your convenience.
September 25, 1981
r • - n . .
•Edgar A. Pash, Team Leader
Eastern Energy and Land Use Team
Enclosure
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FWS/0BS-81/05
August 1981
COAL COMBUSTION WASTE MANUAL:
EVALUATING IMPACTS TO FISH AND WILDLIFE
by
Lars F. Soholt, Project Leader
Robert W. Vocke, Assistant Project Leader
Vanessa A. Harris
Mark J. Knight
Barry Siskind
Dimis J. Wyman, Editor
Division of Environmental Impact Studies
Argonne National Laboratory
9700 South Cass Avenue
Argonne, IL 60439
Project Officer
James Bennett
National Power Plant Team
2929 Plymouth Road
Ann Arbor, Ml 48105
Prepared for
National Power Plant Team
Office of Biological Services
Fish and Wildlife Service
U.S. Department of the Interior
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DISCLAIMER
The opinions, findings, conclusions, or recommendations expressed in this
report are those of the authors and do not necessarily reflect the views of
the Office of Biological Services, Fish arid Wildlife Service, U.S. Department
of the Interior, nor does mention of trade names or commercial products con-
stitute endorsement or recommendation for use by the Federal government.
The correct citation for this report is:
Soholt, L.F., et al. 1981. Coal Combustion Waste Manual: Evaluating Impacts
to Fish and Wildlife. U.S. Fish and Wildlife Service, Biological Ser-
vices Program, National Power Plant Team, FWS/OBS-81/G5. 150 pp.
ii
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Preface
The National Power Plant Team of the U. S. Fish and Wildlife Service, and
Argonne National Laboratory cooperated in producing this manual to provide the
reader with tools for evaluating specific situations which may be encountered
in reviewing plans for the handling and storage of coal combustion wastes.
The manual is designed to be used with the technical report "Handling of
Combustion and Emission - Abatement Wastes from Coal-Fired Power Plants:
Implications for Fish and Wildlife Resources," FWS/0BS-80/33. The technical
report provides more detailed information on the nature of wastes and their
potential impacts to fish and wildlife resources. This manual is cross-
referenced to the technical report by the bracketed numbers in the right-
hand margins of the manual. The numbers refer to pages of the technical
report relevant to the manual topics.
On April 3, 1981, the National Power Plant Team was transferred to the Eastern
Energy and Land Use Team (EELUT) and renamed the National Power Development
Group. Requests for information should be directed to:
Information Transfer Specialist
Eastern Energy and Land Use Team
U. S. Department of the Interior
Fish and Wildlife Service
Route 3 Box 44
Kearneysville, WV 25430
The facilities of Argonne National Laboratory are owned by the United States Government.
Under the terms of a contract (W-31-109-Enfl-38) among the U.S. Department of Energy, Argonne
Universities Association and The University of Chicago, the University employs the staff and
operates the Laboratory in accordance with policies and programs formulated, approved and reviewed
by the Association.
MEMBERS OF ARGONNE UNIVERSITIES ASSOCIATION
The University of Arizona
Carnegie-Mellon University
Case Western Reserve University
The University of Chicago
University of Cincinnati
Illinois Institute of Technology
University of Illinois
Indiana University
The University of Iowa
Iowa State University
The University of Kansas
Kansas State University
Loyola University of Chicago
Marquette University
The University of Michigan
Michigan State University
University of Minnesota
University of Missouri
Northwestern University
University of Notre Dame
The Ohio State University
Ohio University
The Pennsylvania State University
Purdue University
Saint Louis University
Southern Illinois University
The University of Texas at Austin
Washington University
Wayne State University
The University of Wisconsin-Madison
m
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Contents
Page
Preface iii
List of Figures viii
List of Tables x
Acknowledgements xii
INTRODUCTION 1
CHAPTER 1. SITING CONSIDERATIONS 5
Introduction 5
Environmental Criteria 5
Land 7
Air 7
Water 7
CHAPTER 2. HANDLING WASTES . 9
Processing 9
Dewatering 9
Underdrained Impoundments 12
Chemical Fixation 12
Forced Oxidation 12
Transport 12
Belt Conveyors 12
Rail 12
Barge 13
Truck 13
Pipelines 13
Storage 13
Wet Storage 13
Dry Storage 17
Mine Disposal 18
Ocean Disposal 18
Utilization of Coal Ash and FGD Sludge 19
CHAPTER 3. STANDARDS AND CRITERIA 21
Implications for Fish and Wildlife Resources 21
Clean Air Act 21
Clean Water Act 22
Resource Conservation and Recovery Act 23
CHAPTER 4. DESCRIPTION OF MODEL FACILITIES 29
Western Plant 29
Ohio River Valley Plant 33
Texas Plant 34
Southeastern Coastal Plant 35
iv
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Page
CHAPTER 5. WILDLIFE HABITAT LOSS 37
Potential Impacts ..... 37
Quantification 37
Impact Analysis 52
Information Requirements and Sources 53
Mitigative Measures 54
CHAPTER 6. WATER CONSUMPTION 55
Potential Impacts 55
Quantification 55
Estimating Consumptive Use of Water 55
Consumptive Use of Water by Model Plants 56
Impact Analysis 58
Evaluating Consumptive Use of Water 58
Impact of Consumptive Use of Water by Model Plants 58
Information Requirements and Sources 59
Mitigative Measures 60
CHAPTER 7. RUNOFF AND EROSION 61
Potential Impacts 61
Quantification ..... 61
Rainfall Factors 62
Erodibility Factors ..... 62
Topographic Factors 65
Cover Factors 65
Support Practice Factors 65
Impact Analysis 65
Evaluating Erosion Potential - 65
Impact of Runoff Dispersal from the Model Storage Sites 68
Information Requirements and Sources 70
Mitigative Measures 70
Storage-Site Design 70
Physical Methods 71
Chemical Methods 71
Vegetative Methods 71
CHAPTER 8. SEEPAGE OF LEACHATE 73
Potential Impacts 73
Physicochemical Properties of Waster Materials and
Surrounding Substrate 73
Rainfall Zone 75
Quantification and Impact Analysis ... 78
Landfill Leachate Production 78
Pond Leachate Production 78
Leachate Seepage Discharge from the Model Plant Storage Sites ... 81
Information Requirements and Sources 82
Mitigative Measures 83
Flexible Synthetic Liners 84
Admixed Liners 84
v
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Page
Soil Sealants 84
Natural Soil Systems 84
Stabilized Wastes 84
CHAPTER 9. WIND EROSION AND FUGITIVE DUSTING 85
Potential Impacts 85
Quantification 87
Erodibility 88
Surface Roughness 88
Vegetative Cover 88
Qpen-Field Length 89
Climate 89
Impact Analysis 89
Evaluating the Potential for Wind Erosion and Fugitive Dusting . . 89
Impact of Wind Erosion and Fugitive Dust at the Model
Storage Sites 90
Information Requirements and Sources 91
Mitigative Measures 91
Physical Methods 92
Chemical Methods 92
Vegetative Methods 92
CHAPTER 10. CONSEQUENCES TO BIOTA 93
Potential Impact 93
Quantification and Impact Analysis 95
Terrestrial Wildlife 97
Aquatic Biota 100
Impact of Effluent Discharges, Runoff Dispersal, Leachate
Seepage, and Wind Dispersal at the Model Plants 102
Information Sources and Requirements 108
Mitigative Measures 108
CHAPTER 11. RECLAMATION OF WASTE-STORAGE SITES 109
Introduction 109
Predisturbance Site Description 109
Waste-Storage Site Design 110
Waste-Storage Site Revegetation 110
Vegetation Establishment 112
Plant Species Selection 112
Cover Soil Placement 113
Seedbed Preparation 113
Seeding 113
Mulching 114
Postreclamation Land Use and Management 114
Information Requirements and Sources ..... 116
vi
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Page
CHAPTER 12. SOURCES OF CURRENT INFORMATION 117
Publications 117
Federal Agencies 118
Regional Offices of the U. S. Environmental Protection Agency ... 118
State Offices of the U. S. Soil Conservation Service 119
State Offices of the Bureau of Land Management 122
Regional Offices of the Office of Surface Mining Reclamation
and Enforcement 123
Offices of the U. S. Fish and Wildlife Service 124
REFERENCES 125
APENDICES
A. English/Metric Equivalents 131
B. Glossary 133
C. Species of Vegetation Appropriate for Revegetating Waste-
Storage Sites 139
vii
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Figures
Fi gure Page
1 Schematic Representation of Production of Coal Combustion
and Emission-Abatement Wastes ... 3
2 An Outline of the Evaluation of a Coal Ash and FGD
Sludge Waste-Handling Plan 4
3 Evaluation Criteria for Selection of Waste-Storage Sites .... 6
4 Potential Waste-Handling Schemes for Coal Ash and
FGD Sludge 10
5 Diked Pond Constructed Above-Grade 15
6 An Incised Storage Pond 15
7 A Side-Hill Storage Pond 16
8 A Cross-Valley Pond Configuration 16
9 A Heaped Landfill Configuration 17
10 A Side-Hill Landfill Configuration 17
11 A Valley-Fill Storage Configuration 18
12 Leachate Control Methods for Nonhazardous
Waste-Disposal Sites 27
13 Illustration of the Western Model Coal-Fired Power Plant .... 32
14 Illustration of the Ohio River Valley Model Coal-Fired
Power Plant 33
15 Illustration of the Texas Model Coal-Fired Power Plant 34
16 Illustration of the Southeastern Coastal Model
Coal-Fired Power Plant 35
27 Coal Consumption as a Function of Operating Capacity
of an Electric Generating Station 40
18 Volume of Ash as a Function of Weight and Percentage
of Fly Ash and Aggregate 41
19 Percentage S02 Removal Required to Meet USEPA Emissions
Standards 44
20 Amount of FGD Sludge Solids Produced When the Sulfur Content
of Coal is < 2% as a Function of Coal Sulfur Content and
Percent Removal of S02 from the Flue Gas 45
21 Amount of FGO Sludge Solids Produced for Limestone Scrubbing
and Coal Sulfur Contents > 2% as a Function of Sulfur
Content of the Coal and Percent Removal of S02 from the
Flue Gas 46
22 Amount of FGD Sludge Solids Produced for Lime Scrubbing
and Coal Sulfur Contents > 2% as a Function of Coal
Sulfur Content and Percent Removal of S02 from the
Flue Gas 47
23 Amount of FGD Sludge Solids Produced from Combined Lime/
Limestone Scrubbing and Coal Sulfur Contents > 2% as
a Function of Sulfur Content and Percent Removal of
S02 from the Flue Gas 48
v i i i
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24
25
26
27
28
29
30
31
32
33
34
35
36
37
49
50
51
63
64
66
74
76
77
80
81
86
86
Volume of FGO Sludge as a Function of the Percentage
of Dry Solids
Acreage Required to Hold Waste as a Function of Volume
of Waste and Depth of Storage
Schematic of a Generalized Impoundment Difce for the
Western Plant
Average Annual Values of the Rainfall Erosion Index
The Soil-Erodibility Nomograph
Slope Effect Chart
Saturated Hydraulic Conductivities for Different Soil
Types at Unit Gradients
Average Annual Precipitation in the United States
Average Net Precipitation in the United States
Quantity of Leachate from a Landfill
Effect of Sludge Hydraulic Conductivity on the Volume
of Leachate from a Pond -
Transport Modes Through Which Particulate Matter is
Moved by Wind Erosion
Dominant Mode of Windblown Soil Transport as a Function
of Particle Size
Cumulative Grain Size Distributions for Bituminous
Fly Ash
1x
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Tables
Table Page
1 Comparison of FGD Scrubber Sludge Stabilization Methods 11
2 Comparative Summary of Waste Storage/Disposal Options 14
3 Federal Statutes That May Affect the Handling and Release
of Coal Ash and FGD Sludge Wastes 22
4 New Source Performance Standards for Coal-Fired Steam
Electric Generating Plants 23
5 Effluent Standards for Discharges from Coal-Fired Steam
Electric Generating Plants 24
6 USEPA Toxicity Criteria for Classifying Waste as Hazardous ... 24
7 USEPA Guidelines for Controlling Mobilization of Waste
Constituents from Containment 26
8 Ash, Sulfur, and Heat Values of the Coals Utilized by the
Four Model 2100-MWe Coal-Fired Power Plants 30
9 Emission-Control Characteristics of the Four Model
Coal-Fired Power Plants 30
10 Ash Handling at the Four Model 2100-MWe Coal-Fired
Power Plants 31
11 Flue-Gas Desulfurization Sludge Handling at the Four
Model 2100-MWe Coal-Fired Power Plants 31
12 Mulch Factors and Length Limits for Construction Slopes 67
13 Factors Affecting Soil Cation Exchange Capacity 75
14 Potential for Adverse Effects to Groundwater from Seepage
from Unlined Ash and Sludge Waste-Storage Sites 79
15 Generalized Biological Concentration Factors for Elements
in Aquatic and Terrestrial Ecosystems 96
16 Estimated Permissible Ambient Concentrations of Ash and
Sludge Waste Constituents 98
17 Factors by Which Maximum Ambient Concentrations Exceed
Estimated Permissible Ambient Concentrations for a
Waste-Storage Site 99
18 Dilution Factors Required to Achieve Estimated Permissible
Ambient Concentrations for Water of Coal Combustion
Waste Constituents from a Waste-Handling Facility 101
19 Factors by Which Elemental Concentrations in Leachate
Exceed Estimated Permissible Ambient Concentrations
at the Western Model Power Plant 103
20 Factors by Which Elemental Concentrations in Leachate
Exceed Estimated Permissible Ambient Concentrations
at the Ohio River Valley Model Power Plant 104
21 Factors by Which Elemental Concentrations in Leachate
Exceed Estimated Permissible Ambient Concentrations
at the Texas Model Power Plant 105
x
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Table Page
22 Factors by Which Elemental Concentrations in Leachate
Exceed Estimated Permissible Ambient Concentrations
at the Southeastern Coastal Model Power Plant 106
23 Potential Land-Use Categories for Coal Combustion
Waste-Storage Sites 115
xi
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Acknowledgements
The authors are grateful for the guidance and support of the National
Power Plant Team, U.S. Fish and Wildlife Service. Dr. James Bennett and
Dr. R. Kent Schreiber of the Team provided many useful comments and ideas.
The authors also appreciate the helpful reviews by personnel of the Fish and
Wildlife Service regional offices and the U.S. Soil Conservation Service.
Dr. Lee Martin of BlueBird Enterprises, Fresno, California, provided useful
background information on discouraging wildlife from using impoundments.
Mr. William Hallett, Dr. Bernard Jaroslow, Dr. Elizabeth Stull, and
Dr. Jack Zapotosky from the Division of Environmental Impact Studies, Argonne
National Laboratory, and Dr. Barbara-Ann Lewis of Northwestern University
provided helpful reviews of early drafts of the manual. Ms. Alice Packard of
the Division of Environmental Impact Studies provided able technical infor-
mation support.
xii
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Introduction
Increased use of coal in the generation of electricity has become national
policy. With the anticipated accelerated use of coal as an energy source, a
concomitant increase can be expected in the potential for impacts to fish and
wildlife resources. Current new source performance standards promulgated by
the U.S. Environmental Protection Agency (USEPA) require restriction of atmo-
spheric emissions at virtually all coal-fired electric generating stations.
However, disposition of both the pollutants extracted from flue gases and the
reagents used in the extraction process poses a problem that has only recently
received much attention.
Personnel of the U.S. Fish and Wildlife Service are responsible for
assessing the impact of these flue-gas control wastes upon the nation's fish
and wildlife resources. These responsibilities are met through consultation
with other agencies and through review of environmental assessment documents.
The goal of this manual is to provide quantitative guidelines, where possible,
for evaluating the potential extent of habitat disturbance and waste constitu-
ent dispersal. Criteria are also provided for evaluating the potential for
impact from trace elements in the waste. Much impact assessment will be of a
qualitative nature because of the innate imprecision of both the input data
and the assessment tools. Evaluating the significance of coal combustion
wastes to fish and wildlife resources will require the biologist to rely
heavily on his or her own expertise in assessing the nature of fish and wild-
life populations and their interactions with their habitat.
This manual is designed to be used in conjunction with the technical
report entitled "Handling of Combustion and Emission-Abatement Wastes from
Coal-Fired Power Plants: Implications for Fish and Wildlife Resources"
(FWS/OBS-80/33). The technical report provides more detailed information on
the nature of the wastes and their potential impacts to fish and wildlife
resources. The manual is cross-referenced to the report (FWS/OBS-80/33) by
the bracketed numbers in the right-hand margin of the manual pages. These
numbers refer to the pages in the report relevant to the topics discussed in
the manual.
1
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The scope of this manual is restricted to the combustion and emission-
abatement waste-handling systems and the impacts of wastes upon fish and
wildlife resources. Discussion has been limited to the period following
collection of the wastes, and the mechanisms for extracting flue-gas pollu-
tants have not been described in detail. However, the reader may find descrip-
tions of flue-gas control systems in other documents, including "Air Pollution.
Vol. IV, Engineering Control of Air Pollution," edited by Stern (1976). For
general background information about the operation of a coal-fired electric
generating facility, the reader is referred to "Impacts of Coal-Fired Power
Plants on Fish, Wildlife, and Their Habitats" (FWS/OBS-78/29).
The waste stream from a coal-fired electric generating station contains a
number of materials that are potentially harmful to fish and wildlife re-
sources. These materials can include flue-gas-desulfurization (FGD) sludges,
collected fly ash, and boiler ash residue or aggregate (Figure 1). The FGD
sludges are derived from flue-gas sulfur removal systems (scrubbers) and con-
tain varying proportions of sulfates, sulfites, scrubbing reagent (currently
lime and limestone are most commonly used), and trace elements derived pri-
marily from ash impinged by the scrubber sludge. Fly ash is that portion of
coal ash which passes up the flue with the combustion gases; it is commonly
removed from the flue gases by means of electrostatic precipitators, bag
houses, or wet scrubbers. Aggregate consists of ash that has not been en-
trained by the flue gases; it may occur as slag, in which the ash has melted
and fused into a solid mass, or simply as particulate bottom ash. The ashes
contain a variety of trace elements, some of which may be toxic to fish and
wildlife resources.
This manual provides the reader with tools that can be used for evalu-
ating specific situations which may be encountered in reviewing plans for the
handling and storage of coal combustion wastes. The approach taken is out-
lined in Figure 2. The first chapter presents criteria for evaluating the
suitability of a site as a locale for a waste-storage facility. The next two
chapters contain a brief description of waste-handling options and the regula-
tory context for the handling of coal combustion wastes. Impacts from waste-
handling systems are divided into two aspects: (1) disturbance of habitat and
(2) release of potentially toxic materials to the environment. Techniques are
presented for estimating the magnitude of these two aspects and for evaluating
their impacts upon fish and wildlife resources. To help the reader learn how
this manual can be used, data for four model 2100-MWe electric generating
stations are presented as examples.
The International System of Units (SI) is used in this manual with a few
exceptions (e.g., Btu/lb). Definitions and conversion factors (Appendix A)
follow the "Standard for Metric Practice" of the American Society for Testing
and Materials (1976). A glossary of technical terms and acronyms is provided
in Appendix B.
2
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GASES AND
PARTICULATES
NOT COLLECTED BY
EMISSION-CONTROL DEVICES
^ COAL^-
FGD SCRUBBER
SLUDGE
>
COLLECTED
FLY ASH
>
SLAG OR
BOTTOM ASH
>
Figure 1. Schematic Representation of Production of Coal Combustion
and Emission-Abatement Wastes.
3
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Chapter 1
REVIEW
SITE SUITABILITY FOR
WASTE STORAGE
Chapters 2 3 3
REVIEW
WASTE-HANDLING
PLANS AND PERMITS
IMPACT
EVALUATION
>
f HABITAT "N
I DISRUPTION J
(
DISPERSAL OF
WASTE CONSTITUENTS
Chapter 6
WILDLIFE
HABITAT LOSS
Chapter 6
WATER
CONSUMPTION
i
)
1
Chapter 7
Chapt
er 8
Chapter 9
RUNOFF
SEEPAGE
DUSTING
POTENTIAL
POTENTIAL
POTENTIAL
Chapter 10
POTENTIAL CONSEQUENCES FOR
FISH AND WILDLIFE RESOURCES
Chapter 11
REVIEW
RECLAMATION PLANS
(
REVIEW
MITIGATION PLANS
V FINAL \-_
^ EVALUATION H
Figure 2. An Outline of the Evaluation of a Coal Ash and FGD Sludge
Waste-Handling Plan.
4
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Chapter 1
Siting Considerations
INTRODUCTION [98-100]
In reviewing plans for locating a waste-handling facility, the biologist
must consider those nonbiological factors that determine the ability of the
waste-management operation to contain and/or immobilize the wastes. This
involves consideration of many individual factors, the relative importance of
which varies among sites. The factors (evaluation criteria) that may influ-
ence the selection of a storage site can be divided into environmental and
nonenvironmental categories (Figure 3). Evaluation criteria are interdepen-
dent and, thus, fish or wildlife biologists must keep all factors in mind,
although their primary responsibilities center upon the environmental factors.
Additionally, the biologist must recognize that the ecological factors
are closely tied to the other environmental siting criteria. For example, a
site located in a geologically hazardous area (e.g., floodplain) could pose a
threat to fish and wildlife resources should there be catastrophic release of
waste materials.
Selection of a proper site can be a major factor in the mitigation of
impacts from a waste-storage facility.
ENVIRONMENTAL CRITERIA [98]
Most of the environmental criteria are not directly related to fish and
wildlife resources, but they do affect the future use of a site and the capa-
bility of a site to support a waste facility without adverse impacts to the
environment. The following questions should be considered in evaluating the
potential for environmental impacts from the siting of a waste-hand1ing facil-
ity. These questions are not definitive but are a sample of the questions
that may be asked. Proper siting of the facility is an important factor in
mitigating impacts from a waste operation. Impacts can be lessened by siting
facilities in areas that are not ecologically sensitive or in areas where the
release of the wastes is unlikely.
5
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ENVIRONMENTAL CRITERIA
NONENVIRONMENTAL CRITERIA
Figure 3. Evaluation Criteria for Selection of Waste-Storage Sites.
6
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Land
• Does the site contain important or unique agricultural soils?
• Are the soils of the site suitable for supporting a waste-storage
facility with minimal dispersal of waste constituents?
• Does the area around the site contain unique or sensitive terrestrial
habitats?
• Does terrestrial habitat on the site support populations of rare,
endangered, or commercially valuable species?
• Is terrestrial habitat at the site of high quality or is it the best
quality of that habitat in the region?
• Will wildlife use of the area around the site be affected by noise
generated during waste-handling operations?
• Does current land use of the area around the site conflict with use
of the site as a waste-storage facility?
• Can the site be restored to its current land use after closure of
the waste-handling operation?
• Will storage facilities on the site cause scenic or aesthetic effects
such as visible intrusion into the scenic view?
• Will a waste-storage operation disturb cultural resources such as
unique archeological, historical, or paleontological areas^
• Can these cultural resources be studied prior to construction of a
storage facility?
Air (Wind Speed and Direction)
• Is the site susceptible to wind erosion and resulting fugitive dust
from the stored waste?
• Could downwind habitat be affected by fugitive dust?
Water
• Can surface waters safely accept discharges from the site while
maintaining adequate water quality?
• Is sufficient surface water available to support consumptive uses of
waste handling without degradation of surface water biota?
• Will construction of a storage facility result in diversion of
surface water flows?
7
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• Will new impoundments attract wildlife, possibly delaying migrating
waterfowl or resulting in toxic effects to wildlife?
• Is the underlying groundwater susceptible to contamination from the
waste-storage site?
• Will the site comply with USEPA guidelines for maintaining a minimum
distance of 250 m between storage sites and groundwater supplies?
• Is the water table more than 1.5 m below the storage area?
• Is the site located in the 100-year floodplain and/or coastal zone?
• Will the facilities or practices at the storage site restrict the
flow of the 100-year flood, reduce the temporary water storage
capacity of the floodplain, or result in washout of solid waste?
• Will use of the site for waste storage alter or destroy unique
aquatic habitat, e.g., wetlands?
• Is there potential for detrimental effects to populations of rare,
endangered, or commercially valuable aquatic species?
8
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Chapter 2
Handling Wastes
Handling of coal ash and flue-gas-desulfurization (FGD) wastes for ulti-
mate disposal involves three steps: processing, transport, and storage. As
shown in Figure 4, the combinations of methods used may vary widely and the
choice is a function of the characteristics of the waste, method of storage,
land availability, cost, and potential for environmental disturbance.
Coal ash processing is usually unnecessary but may be appropriate for
some waste-handling methods. For example, water must be added to the ash for
pond storage and slurry pipeline transport. The ash may also be blended with
FGD sludge to act as a sludge stabilizer.
For convenient handling, processing of FGD sludge is necessary because
its thixotropic nature (i.e., it tends to become fluid when disturbed) makes
sludge difficult to handle. As a result, the sludge must be stabilized, or
fixed, so that it does not flow prior to disposal. The available stabiliza-
tion methods are dewatering, underdraining impoundments, chemical fixation,
and forced oxidation. A comparison of these methods is given in Table 1.
Dewatering [29-30]
Dewatering reduces the moisture content of the ash or FGD sludge slurry
and, thus, the land area requirements for waste storage. Water removed from
the sludge during dewatering may be recycled to the scrubber, resulting in
decreased consumptive water use. Water removal also results in reduced poten-
tial for seepage of soluble trace elements into the surrounding environment.
Pond settling and thickening are used almost universally to concentrate sludge
or slurry solids. Chemical dewatering aids may be added to the sludge to
cluster colloidal suspensions, allowing them to settle out of suspension.
Following primary dewatering by one of the steps discussed above, the FGD
sludge may undergo secondary dewatering by vacuum filtration or centrifuga-
tion.
PROCESSING
[29-31]
9
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Figure 4. Potential Waste-Handling Schemes for Coal Ash and FGD Sludge. Modified from
GAI Consultants (1979).
-------
Table 1. Comparison of F6D Scrubber Sludge Stabilization Methods3
Pewaterin9 Underdraining Chemical Forced
Settling pond Thickener Vacuum filter Centrifuge impoundment fixation oxidation
Sensitivity to
flow variations
and solids content
Low
High
High
Medium
Low
Low
Low
Maintenance
required
Low
Medium
High
High
Low
Medium
High
Land commitments
for process
High
Low
Low
Low
High
Low
Low
Energy require-
ments
Low
Medium
High
High
Low
Medium
Medium
Percent reduction
in sludge volume
10 to 90%
10 to 93%
10 to 77%b
10 to 75%b
n.a.c
n. a.
n. a.
Seepage potential
High
Low to high
Low
Low
Low
Low
Low
Ease of sludge
removal
Low
High
High
High
n. a.
High
High
Based on personal communication and data from U.S. Environmental Protection Agency (1980b), Metcalf & Eddy (1972),
.and Fair et al. (1966-1968).
Percent reduction following primary dewatering.
n.a. = not applicable because water is not withdrawn from the waste.
-------
Underdrai ned Impoundments
[30]
Underdrained impoundments contain a drainage bed in the floor of the
impoundment. The drainage bed collects seepage, which is removed and may be
reused as makeup water in the scrubber. This method allows the pond to be
used as an acceptable landfill because collection of the seepage greatly
reduces infiltration of waste constituents into the soil and groundwater.
However, pond liners may be required where soils are highly permeable or where
there is a high water table.
Chemical Fixation [30-31]
Chemical fixation involves treatment of the FGD sludge with chemical
additives or coal ash, resulting in a solidified waste that can be handled
much more readily than the original sludge. The permeability of the waste is
decreased, and the amount of material leached from the waste is reduced.
However, the addition of ash to FGD sludge results in higher concentrations of
potentially mobile elements than are found in the sludge alone.
Forced Oxidation [30]
Forced oxidation involves forcing air through the sludge, thereby accel-
erating the oxidation of calcium sulfite to calcium sulfate. Calcium sulfate
sludge has a higher solids settling rate, is easily dewatered, and is less
thixotropic than calcium sulfite. Calcium sulfate may also be marketable,
lessening the need for long-term storage. In addition, forced oxidation
reduces the potential for sulfite contamination of the environment.
TRANSPORT
There are five methods that can be used for transportation of wastes to
disposal sites: belt conveyors, rail, barge, truck, and pipeline. The design
and selection of an ash or scrubber sludge transport system depends primarily
on whether the transported material is handled as solids (dry) or as a slurry
(wet).
Belt Conveyors
Belt conveyors are limited to disposal of dry wastes. They may be used
for transport of dewatered FGD sludge as well as ash. Short conveyors have a
high degree of flexibility and can be moved to different locations, whereas
long conveyors (several hundred meters or more) are usually permanent instal-
lations. Impacts from this mode of transport would be localized because
conveyors are not used for long distance (several kilometers) hauling.
Rail
Rail can be used to transport dry ash and fixed sludge. Dry ash disposal
using conventional side-dumping or bottom-dumping cars has been shown to be
effective. However, there are problems in handling wet sludge, and specially
12
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designed cars have not yet been developed. It is possible to use existing
commercial rail-haul routes or to haul on tracks and rights-of-way controlled
by the utility. Hauling by commercial routes is not economically competitive
at distances less than 80 km. Fugitive dust in transit could be a problem and
might require that the cars be covered or that dust-suppressant sprays be
used.
Barge
Barge transport may accommodate wet or dry sludges and has high system
reliability and very low unit costs. However, it does not promise wide appli-
cability because of limited transport routes and required special loading and
unloading facilities. Except for ocean disposal, barging alone would not get
the wastes to the disposal site.
Truck
Truck transport may be used for wet or dry ash and sludge hauling, but is
preferred for dry hauling. Trucking is the most flexible and most widely used
mode of dry ash and sludge transportation. A principal disadvantage of truck
transport is high public visibility. The quantity of materials produced at a
fully operational station require a nearly continuous flow of truck traffic in
and out of the station site. Fugitive dusting problems from open trucks can
require the use of dust-control measures.
Pipe!ines
Pipelines are used to transport wet ash and sludge slurries for distances
up to 15 km. A typical pipeline transport facility consists of a single
pumping station, although more than one may be required for long distances or
uphill traverses. Two full-size pipelines are often required--one pipeline
for transporting the slurry to the storage site, the other for returning
supernatant to the station. Conventional pumping and piping materials are
generally suitable if the pH is near neutral, but the abrasive character of
the sludge and ash may lead to pipeline failure resulting from erosion.
STORAGE [31-37]
There are two basic types of storage for coal ash and FGD sludge wastes:
wet (ponding) and dry (landfil1ing). Two other options are deposition of the
wastes in mines or in the ocean. A comparison of these methods is given in
Table 2.
Wet Storage
The four wet storage pond configurations used most often are the diked
pond, incised pond, side-hill pond, and cross-valley pond. The following
illustrations (Figures 5 through 8) are reproduced from Duvel et al. (1979).
The arrows in the illustrations indicate the position and direction of view
for the cross section of each configuration.
13
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Table 2. Comparative Summary of Waste Storage/Disposal Options3
Wet storage
Dry storage
Mine disposal
Ocean disposal
Method
Ponding of
waste
Landfilling of
waste
Backfilling mines
with waste
Depositing waste in
the ocean
Applicability
Most wastes
and handling
systems except
double alkali
Dry or fixed
waste
Mainly dry or
fixed wastes
Dry or fixed wastes
Advantages
Simple
Low land
requirement
Sites available
No new land preempted
Versatile
No impoundment
requi red
No new land pre-
empted
Low traffic
potential
Low seepage
potential
Aids in mine
stabi1ity
Low dust
potential
Reclamation
practicable
No attraction
for biota
Disadvantages
High land
requirement
Sludge fixation
required
High leaching
potential
Limited to coastal areas
Impoundment
construction
High dust
potential
Potential for
acid mine drain-
age synergisms
May be legally unaccept-
able
High potential
for seepage
High traffic
potential
May require that
mine be dewatered
Sludge
instability
Requires
diversion of
runoff
Plant must be
near mine site
Reclamation
uncertain
May require
further proces-
sing of waste
Liners may
be required
Ponds may
attract biota
aSources: Frascino and Vail (1976), Ansari et al. (1979), and Duvel et al. (1979),.
14
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The diked pond is the most common pond in use, requires a
nearly level site, and is contained within a perimeter
embankment or dike.
An incised pond is contained in an excavation below the
existing grade and is most appropriate for use where the
bedrock and water table are deep. The incised pond is
preferable where space is limited for dikes or where
excavated materials are unsuitable for dike construction.
Figure 6. An Incised Storage Pond.
15
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The side-hi 11 pond takes advantage of local hilly terrain
to provide one or two sides of an impoundment. However,
it may be difficult to safely construct a large side-hill
pond on steeply sloping sides.
Figure 7. A Side-Hill Storage Pond.
A cross-valley pond is formed by constructing a dam across
a portion of a natural valley between the valley walls.
The design is critical because, in addition to waste
storage, it must provide for controlled storage and dis-
charge of the natural water flow in the valley.
Figure 8. A Cross-Valley Pond Configuration.
16
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Dry Storage
Dry storage, or landfilling, of sludge requires blending of dry material
(e.g., ash) with sludge to aid in reducing the moisture content. Dry storage
usually requires construction of facilities to divert runoff from landfill
areas. The following illustrations of landfill configurations (Figures 9
through 11) are reproduced from Duvel et al. (1979). The arrows in the illus-
trations indicate the position and direction of view for the cross section of
each configuration.
The heaped fill is the simplest landfill configuration and
is typically used in areas with level terrain. Ground-
water pollution, slope stability, and site preparation
problems are minimal when the site is properly managed.
However, the landfill has a high visibility.
Figure 9. A Heaped Landfill Configuration.
The side-hill construction is often used in hilly or
gently sloping terrain. Properly constructed, side-hill
landfills may blend well with the existing terrain.
Figure 10. A Side-Hill Landfill Configuration.
17
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The valley-fil 1 is the most common type of landfill in
areas of hilly terrain. Control of surface water and
groundwater is necessary since valleys are natural avenues
of surface runoff and, in some cases, of springs along
side slopes.
Mine Disposal
Mine disposal of coal ash has been practiced at a number of mines, but no
full-scale operation of FGD sludge disposal in surface or deep mines has been
developed. Mine disposal has a potential for impacts on groundwater or sur-
face waters by dispersal of soluble materials from wastes deposited in the
mines. Mine disposal of coal ash or FGD sludge may be dependent on guidelines
for the use of toxic materials as backfill in both surface and deep mines
(30 CFR 816.103, 817.103).*
Ocean Disposal
Ocean disposal of waste sludge may be an available alternative for some
coastal utilities. However, ocean dumping is being discouraged by government
agencies.. Certain compounds contained in waste sludge may not be disposed of
in the ocean. These toxic pollutants are listed in 40 CFR 401, and control of
these pollutants would be required if an ocean dumping permit were granted.
Because of potential sulfite toxicity effects, ocean disposal is not appli-
cable to untreated, sulfite-rich FGD sludges.
Title 30, Code of Federal Regulations (CFR), Sections 816.103 and 817.103.
Such citations are usually abbreviated as indicated.
Figure 11. A Valley-Fill Storage Configuration.
18
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UTILIZATION OF COAL ASH AND FGD SLUDGE
[37-39]
Coal ash can be recycled for such uses as cement additive, fill material
for road construction sites, stabilizer in pavement, and filler in asphalt
mix. Ash utilization is also under study for agricultural and land reclama-
tion applications, water treatment, grouting mixes, and fire abatement in
landfills or coal mine refuse piles. Currently, less than 25% of the coal ash
being produced is recycled.
The prospects for large-scale utilization of FGD sludge are minimal. On
a small scale, it appears feasible to use sludge as a soil additive to improve
soil porosity or nutrient enrichment, for blending with coal ash in landfill
and surface reclamation, as fill in pavement, as liners in waste ponds, and as
a source of gypsum.
19
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Chapter 3
Standards and Criteria
IMPLICATIONS FOR FISH AND WILDLIFE RESOURCES
[97]
The U.S. Congress has passed statutes regulating solid waste handling in
order to protect human health and the environment from deleterious effects of
hazardous solid wastes. Implicit in protection of the environment is protec-
tion of the nation's fish and wildlife resources. The primary thrust of the
regulations, promulgated and proposed, is to contain toxic wastes in the
storage area. In general, this should lead to a reduction in the amounts of
hazardous material reaching areas where they might affect fish and wildlife
resources. The regulations do not, however, require recovery of wildlife
habitat that may be preempted by the waste-storage facility, nor do they
ensure that wildlife will not use potentially toxic drinking waters in impound-
ments.
An outline of the federal statutes as they pertain to various aspects of
the waste-handling process is presented in Table 3. The three major federal
laws affecting coal ash and FGD wastes are the Clean Air Act, Resources Con-
servation and Reclamation Act (RCRA), and Clean Water Act. In addition to
federal regulations, local and state regulations will also place constraints
upon the manner in which ash and sludges wastes may be handled.
CLEAN AIR ACT [97]
The Clean Air Act (Public Law 90-148, as amended) was passed in response
to increasing concern for maintaining air quality at a level compatible with
human health and environmental integrity. Ttiis act has a direct impact upon
the amount of disposable waste produced because, under regulations promulgated
in response to the act, coal-fired generating stations must employ emissions-
control technology. Thus, most of the particulates (fly ash) and sulfur
compounds must be removed from the flue-gas stream, thereby producing the bulk
of the solid wastes to be handled by the utility. For coal-fired steam elec-
tric generating plants, the standards (40 CFR 60) presented in Table 4 must
be met.
21
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Table 3. Federal Statutes That May Affect the Handling and Release of
Coal Ash and FGD Sludge Wastes3
Affected process/legislation
PRODUCTION
Clean Air Act of 1973 and
Amendments of 1977
HANDLING
Resource Conservation and Recovery
Act of 1976
Dam Safety Act of 1972
Surface Mining Control and
Reclamation Act of 1977
Occupational Safety and Health Act
of 1970
Federal Coal Mine Health and Safety
Act of 1969
AERIAL RELEASES
Clean Air Act of 1973 and
Amendments of 1977
Hazardous Materials Transportation
Act of 1969
Federal Coal Mine Health and Safety
Act of 1969
Occupational Safety and Health Act
of 1970
GROUNDWATER CONTAMINATION
Resource Conservation and Recovery
Act of 1976
Safe Drinking Water Act of 1974
SURFACE WATER CONTAMINATION
Clean Water Act of 1977
Resource Conservation and Recovery
Act of 1976
MARINE WATER CONTAMINATION
Clean Water Act of 1977
Resource Conservation and Recovery
Act of 1976
Marine Protection Research and
Sanctuaries Act of 1972
aData from GAI Consultants (1979).
Administrative authority
Environmental Protection Agency
Environmental Protection Agency
Army Corps of Engineers
Office of Surface Mining,
Reclamation and Enforcement
Occupational Safety and Health
Admini stration
Mining Enforcement Safety
Admini stration
Environmental Protection Agency
Department of Transportation
Mining Enforcement Safety
Administration
Occupational Safety and Health
Administration
Environmental Protection Agency
Environmental Protection Agency
Environmental Protection Agency
Environmental Protection Agency
Environmental Protection Agency
Environmental Protection Agency
Environmental Protection Agency
Permits required
Prevention of Significant Deterio-
ration (PSD); New Source Review
Hazardous Waste
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Hazardous Waste
Underground Injection
National Pollutant Discharge Elimi-
nation System; Dredge and Fill
Hazardous Waste
National Pollutant Discharge Elimi-
nation System
Hazardous Waste
Ocean Dumping
CLEAN WATER ACT [97]
The Federal Water Pollution Control Act (Public Law 92-500) as amended by
the Clean Water Act has an established goal of eliminating the discharge of
pollutants into the nation's water bodies. The act has expressly declared
22
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Table 4. New Source Performance Standards for Coal-Fired
Steam Electric Generating Plants
Plant
bui It
Emissions
product
Between 12 August 1971
and 18 September 1978
After 18 September 1978
Particulates
^ 43 ng/J (0.10 lb/Btu)
S 13 ng/J (0.03 lb/Btu)
and S IX of potential
combustion concentration
S02
^ 520 ng/J (1.2 lb/Btu)
^ 520 ng/J (1.2 lb/Btu)
and ^ 10% of potential
combustion concentration
or
260 ng/J (0.6 lb/Btu)
with a maximum release
of 30% of potential com-
bustion concentration
no2
S 300 ng/J (0.7 lb/Btu)
^ 210 ng/J (0.5 lb/Btu)
Source: 40 CFR 60.
that regulations be promulgated so as to protect the biota of freshwater and
marine systems. Under the authority of this act, the U.S. Environmental
Protection Agency (USEPA) has issued standards for discharges from coal ash
and FGD sludge waters. Current effluent standards for discharges from steam
electric generating stations are presented in Table 5. For new sources, there
may be no discharge that contains suspended solids from fly ash transport
waters. Unless the operator of a waste-handling site can show extenuating
circumstances, runoff from waste-storage sites cannot contain in excess of
50 mg suspended solids per liter of water. These effluent standards may be
changed in the near future.
RESOURCE CONSERVATION ANO RECOVERY ACT [93-96]
The Resource Conservation and Recovery Act (Public Law 94-580) has a
major impact upon the handling of coal ash and FGD sludges as solid waste.
This act is intended to prohibit open, uncontrolled dumping and promote waste-
handling techniques that will reduce adverse effects to health and environ-
ment. The USEPA (1979a, 1979b, 1980a) has promulgated standards and criteria
for carrying out these goals. To date, utility wastes have not been labeled
as hazardous, but some data suggest that they may occasionally exceed the
USEPA criteria for toxicity hazard. Current USEPA criteria for classifying
wastes as toxic hazards are listed in Table 6.
23
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Table 5. Effluent Standards for Discharges from
Coal-Fired Steam Electric Generating Plants
Standards for ash and
Parameter FGD sludge liquors
pH 6-9
Total suspended solids 100 mg/L (daily maximum)
30 mg/L (30-day average)
Oil and grease 20 mg/L (daily maximum)
15 mg/L (30-day average)
Source: 40 CFR 423.
Table 6. USEPA Toxicity Criteria for Classifying Waste as Hazardous3
Criterion concentration
Contaminant in leachate (mg/L)
Arsenic 5-0
Barium 100.0
Cadmium 10
Chromium 5.0
Lead 5.0
Mercury 0.2
Selenium 1-0
Silver 5.0
Endrin 0.02
Lindane 0.40
Methoxychlor 10.0
2,4-Dichlorophenoxyacetic acid (2,4-D) 10.0
2,4,5-Trichlorophenoxypropionic acid (2,4,5-TP) 1.0
Toxaphene 0.5
aFrom U.S. Environmental Protection Agency (1980a). Criteria are 100 times
the USEPA National Interim Primary Drinking Water Regulations. _ The USEPA
(1980a) requires a standard method for testing a waste for toxic hazard.
If leachate from this test contains any of the above contaminants in excess
of the criteria in this table, the waste is to be classified as hazardous.
24
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Under RCRA, the USEPA (1979a, 1979b) has also issued regulations and
guidelines for locating and designing nonhazardous waste sites, including
sites for coal ash and FGD sludge. These regulations and guidelines indicate
that:
A site may not be located in:
• Environmentally sensitive areas, such as 100-year floodplains,
wetlands, or permafrost
• Critical habitat for endangered species
• Seismically active areas
• Recharge zones of sole-source aquifers
Additionally, the waste-handling facility must not discharge pollutants into
surface waters in violation of the requirements of the National Pollutant
Discharge Elimination System (NPDES) under the Clean Water Act. The facility
should be designed such that mobilization of waste constituents is minimized
by incorporating the guidelines in Table 7 and Figure 12. These USEPA guide-
lines are not mandatory at this time but should be considered by the states in
developing waste-handling regulations. Site monitoring is required to assess
the success of containment during the lifetime of the facility.
25
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Table 7. USEPA Guidelines for Controlling Mobilization of
Waste Constituents from Containment3
Leachate control
• Unless the groundwater in the area is already unusable, the bottom of the
landfill should be maintained at least 1.5 m above the seasonal high
water table.
• Runoff diversion structures should be constructed which are capable of
diverting all runoff from a 10-year, 24-hour storm.
• If needed, dikes to prevent inundation by the 100-year flood should be
included.
• Final grade of the landfill should be between 2 and 30% so that erosion
and infiltration are minimized.
• Terraces should be included at 6-m vertical intervals.
• The final soil cover should be seeded to minimize erosion and maximize
evapotranspi ration.
• Either low permeability or high permeability soils should be used as
cover, depending upon design considerations for leachate control.
• Liner materials should have a permeability coefficient of 1 v 10-7 cm/s
or less.
• Minimum thickness for in-place or constructed soil liners is 30 cm, and
for synthetic membranes is 20 mils.
• Synthetic liners should be covered and rest on sufficient granular
material to prevent puncture.
• Liner grades of 1% or more are required.
• Collected leachate must be treated before discharge.
Runoff control
• The landfill should be located in an area where drainage from adjacent
lands onto the site is minimal.
• Suitable runoff diversion ditches should be constructed surrounding the
site.
• Landfill surface should be sloped to grades not in excess of 30%.
• Well-compacted, fine-grained soil should be used for final cover.
• Offsite runoff and uncontaminated onsite runoff should be routed to a
sedimentation basin prior to discharge. Contaminated onsite runoff must
be collected and decontaminated prior to discharge.
aAdapted from GAI Consultants (1979).
26
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SOIL LINER
CASE I
NATURAL HYDROGMEOLOQIC CONDITIONS
SUFFICIENT TO PREVENT CQNT AWN#»TlON,
NO CONTROL REQUIRED
case n
LINER REDUCES ANO CONTROLS LEACHATE
OUMtTtTf ANO IMPROVES QUALITY BY SOIL
ATTENUATION. ADDITIONAL LEACHATE
IMPROVEMENT BY DILUTION OR ATTENUATION
IN SITE SOIL8
i
CASE HI
NATURAL CONDITIONS PROVIDE ONLY
MINIMUM LEACHATE IMPROVEMENT. LINER
AND LEACHATE COLLECTION REQUIRED.
J£,
CASE IE
NATURAL CONDITIONS PROVIDE LITTLE OR
NO LEACHATE IMPROVEMENT. MULTIPLE
LINER8 £Ng LEACHATE COLLECTION REQUIRED.
Figure 12. Leachate Control Methods for Nonhazardous Waste-Disposal Sites.
The lines at the bottom of the drawings represent the water
table. From GAI Consultants (1979).
27
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Data on four model 2100-MWe coal-fired power plants are presented to
illustrate how to use the guidelines given in this manual for assessing pro-
posed coal combustion waste-storage sites, management of active sites, and
reclamation of former sites. Each plant has a nominal operating lifetime of
40 years. Values presented for quantification purposes are approximate values
and, due to rounding, recalculation will not result in the exact values pre-
sented here. [Numbers are rounded in accordance with the rules outlined in
the style manual of the Council of Biology Editors (1978)]. Model plant
locations and coal characteristics are presented in Table 8. Coal types
reflect regionally observed variations in coal composition. Operating parame-
ters of the four plants, which are characteristic of current power plants
coming on line, are presented in Table 9. Waste-handling practices are sum-
marized in Tables 10 and 11.
WESTERN PLANT [135-139]
At the Western plant (Figure 13), ash residues are stored in a large
upland surface coal mine 8 km (5 miles) from the plant, near the Powder River
in Wyoming. The sludge storage site, a diked pond, is located in an alluvial
area more than 300 m from the river and meets applicable state and federal
specifications. The soil type of the storage pond area is Kim loam, an
Entisol, with 0 to 3% slope. The area is currently managed for range and
wildlife habitat but has potential for being managed for irrigated hay, small
grain, and pasture. Natural vegetation is dominated by plains grassland, but
range conditions have deteriorated slightly-allowing annual invaders, prickly
pear cactus, and short grasses to appear. Forage value of the area is higher
than most habitat types in the region, and similar habitats available for
wildlife are in limited supply. Endangered and threatened species have not
been reported in the area.
29
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Table 8. Ash, Sulfur, and Heat Values of the Coals Utilized
by the Four Model 2100-MWe Coal-Fired Power Plants3
Ash Sulfur Heat value Sulfur'5
Model plant Coal type (%) (%) (BUi/lb) (lb/106 Btu)
Western
Low-sulfur
6.0
0.48
8,200
0.58
Ohio River
valley
High-sulfur
10
3.5
11,400
3.07
Texas
Lignite
10
0.8
7,705
1.04
Southeastern
coastal
High-sulfur
12.4
1.6
13,135
1.22
The model plants are designated as 2100-MWe plants, the MWe indicating
units of electric power as opposed to, for example, thermal power (MWt).
All model plants are assumed to operate at 70% of capacity over one year
.(i.e., the plant factor = 0.7).
Sulfur (lb/10s Btu) = sulfur (%) ~ [heat value (Btu/lb) x 106].
Table 9. Emission-Control Characteristics of the Four
Model Coal-Fired Power Plants
S0P control
Model plant
FGD reagent
% S02 removal3
Western
Lime
70
Ohio River valley
Lime
90
Texas
Limestone
74
Southeastern coastal
Limestone
90
Particulate control for all model plants
• 85% of ash is fly ash.
¦ Electrostatic precipitators are used.
• 99.5% of the ash is removed from the flue stream.
¦ About 0.135 of the fly ash is removed from the flue gas
by impingement on FGD reagent.
aFrom Figure 19, using the data for sulfur (lb/106 Btu)
from Table 8.
30
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Table 10. Ash Handling at the Four Model 2100-MWe Coal-Fired
Power Plants
Model plant
Storage option
Design
Transport
Water content
of
thickened waste
Western
Deposited dry in
surface mine
Not applicable
Truck
Not applicable
Ohio River
valley
Slurried with sludge
to impoundment
Diked pond
Pipeline
65%
Texas
Dry-mixed with
sludge in landfill
Heaped landfill
Truck
Not applicable
Southeastern
coastal
Slurried with sludge
to impoundment
Above-grade
diked pond
Pipeline
65%
Table 11. Flue-Gas Desulfurization Sludge Handling at the
Four Model 2100-MWe Coal-Fired Power Plants
Model plant
Storage option
Design
Transport
Water content
of
thickened waste
Western
Slurried to
impoundment
Incised, diked
pond
Pipeline
65%
Ohio River
valley
Slurried with ash
to impoundment
Above-grade
diked pond
Pipeline
35%
Texas
Mixed with dry
ash in landfill
Heaped landfill
Truck
50%
Southeastern
coastal
Slurried with ash
to impoundment
Above-grade
diked pond
Pipeline
35%
31
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Ash is used as fill material in the surface coal mine providing coal for
the Western plant. Scrubber sludge from the power plant contains 15% solids
and is mechanically thickened to 35% solids by weight; water from the thicken-
ing process is recycled in the scrubbing system. Supplementary water is
pumped from the Powder River. Thickened sludge is piped to the partially
incised, diked storage pond. The storage site has been excavated to a depth
of 3 m, and the excavated soil material is used in the construction of re-
straining dikes to allow scrubber sludge to be deposited 9.1 m deep. The
above-grade restraining dike is 7.6 m high and 65.5 m wide at the base. The
outer slope of the dike has a 5:1 grade, the inner slope a 3:1 grade. Jhe
storage site occupies approximately 53 ha (130 acres), including the area
occupied by waste, restraining dikes, and associated pipelines and access
roads. This area is sufficient to hold the waste produced over the 40-year
lifetime of the plant. The pond is lined with clay having a hydraulic con-
ductivity of 7.5 x 10-7 cm/s. The pond has an effluent discharge facility. As
individual cells of the storage pond are filled, they will be stabilized for
reclamation by natural evaporation, and the stabilized storage area will be
graded, covered, and revegetated.
Figure 13. Illustration of the Western Model Coal-Fired Power Plant.
32
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OHIO RIVER VALLEY PLANT
[139-143]
The Ohio waste-storage site (Figure 14) is located in an alluvial area
adjacent to the Ohio River. The diked storage pond is 300 m or more from the
river and meets all applicable state and federal specifications. Levees will
be constructed as needed to protect the area from flooding. The storage pond
area soil type is Huntington silt loam, a Hoi 1isol, which is nearly level.
Approximately 50% of the area is currently used for row crops (corn and soy-
beans); the other 50% was formerly cultivated but has been abandoned and is
reverting to woodland. Huntington silt loam is well suited for corn and small
grain crops, grasses and legumes, wild herbaceous upland plants, and hardwood
plants—making habitat for open-land wildlife or woodland wildlife. Wetland
wildlife are also found in the area due to the proximity of satisfactory habi-
tat along the Ohio River. Bald eagles (Haliaeetus leucocephalus), a threat-
ened species, and Virginia big-eared bats (Plecotus townsendil virginianus),
an endangered species, have been reported in the area.
Ash at the Ohio plant is deposited with scrubber sludge in a diked stor-
age pond. The diked pond is completely above-grade because of the shallow
water table. Restraining dikes are 10.7 m high and 89.9 m wide at the base.
The outer slope of the dike has a 5:1 grade, the inner slope a 3:1 grade. The
combined ash and sludge is deposited to a depth of 9.0 m. The square storage
site, including a 30.5-m buffer zone (with the deposited waste, restraining
dikes, and associated access roads, etc.), will occupy about 670 ha (1700
acres) at the end of plant operations. The pond is lined with clay having a
hydraulic conductivity of 5 x 10-7 cm/s. The combustion wastes are stabilized
to 65% solids by weight in the storage pond by natural evaporation and by
removal of excess supernatant through a controlled-flow effluent discharge
after the suspended solids have settled. The stabilized storage area will be
graded, covered, and revegetated.
Figure 14. Illustration of the Ohio River Valley Model Coal-Fired Power Plant.
33
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TEXAS PLANT
[143-147]
The Texas waste-storage site (Figure 15) is located near Sam Houston
National Forest. The storage site soil type is Tuckerman loam-heavy sub-
stratum, an Alfisol, with less than 0.3% slope. The area is currently managed
for loblolly pine (Pinus taeda) and slash pine (Pinus el 1iottii) timber and
woodland grazing. The most important forage plants are sedges, which make up
80% of the herbaceous understory. Although the area is managed in part as
woodland, equipment limitations, plant competition, and seedling mortality are
severe. Wildlife species are abundant, and red wolves (Canis rufus), an
endangered species, have been reported in the area.
At the Texas plant, scrubber sludge is mechanically thickened to 50%
solids by weight. Thickened sludge is mixed with ash residues and landfilled
to a thickness of 4.6 m. Prior to deposition of the wastes, 0.6 m of topsoil
is removed from the storage site. The completed storage site will occupy
approximately 730 ha (1800 acres). The landfill site will not be lined. As
the site is filled, it will be capped with a clay liner, covered with stored
topsoil, and revegetated.
Figure 15. Illustration of the Texas Model Coal-Fired Power Plant.
34
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SOUTHEASTERN COASTAL PLANT
[147-150]
The Southeastern coastal waste-storage site (Figure 16) is located on the
North Carolina coastal plain. The diked storage pond is 300 m or more from
the nearest stream and meets all applicable state and federal specifications.
The soil type of the storage pond area is a sandy loam, an Ultisol, which is
nearly level. Approximately 50% of the area is currently used for row crops
(corn and soybeans); the other 50% is in the early stages of old-field
succession. Natural vegetation types for the area are oak-pine (Quercus-
Pi_nus) and tupelo-sweet gum-bald cypress (Nyssa sp.-Liquidambar styraciflua-
Taxodium distichum). A number of wildlife species use the site. Bald eagles
(Haliaeetus leucocephalus), a threatened species, and American alligators
(A11igator mississippiensis), an endangered species, have been reported in a
nearby small stream and large estuary.
Scrubber sludge and ash from the Southeastern coastal plant are stored in
an above-grade, diked storage pond with an underdrain system. Underdrainage
is recycled to the scrubber system. Excess supernatant is removed through a
controlled effluent discharge after adequate settling of suspended solids has
occurred. Restraining dikes are 7.6 m high and 65.5 wide at the base, with
the outer slope of the dike at a 5:1 grade, the inner slope at 3:1. Combus-
Figure 16. Illustration of the Southeastern Coastal Model Coal-Fired
Power Plant.
35
-------
tion wastes are deposited to a depth of 6.0 m. The storage site is surrounded
by a 30.5-m buffer zone and occupies 730 ha (1800 acres). The pond is lined
with clay, having a permeability of 1 x 10-7 cm/s, below the underdrain sys-
tem. When the storage pond is filled and stabilized to 65% solids, the stor-
age area will be graded, covered, and revegetated.
36
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Chapter 5
Wildlife Habitat Loss
POTENTIAL IMPACTS
[41-42]
Withdrawal of land from use by wildlife may have marked impacts upon
local faunal populations. Members of the less mobile species may be killed by
clearing and construction activities. Although mobile species can move into
adjacent habitats, the resulting increased competitive pressures may prove to
be detrimental to the population as a whole. Because of the complex network
of interactions influencing a population's success, it is difficult to assess
the potential magnitude and impact of increased competition pressures due to
displacement of individual wildlife. Available information is largely anec-
dotal, and predictions of adverse impact are based upon the assumptions that
habitats are normally at carrying capacity and increased competition is detri-
mental to a population. These assumptions have not been rigorously tested.
Of particular concern is the displacement of wildlife populations from
habitat that is important to their life history, e.g., winter foraging, nest-
ing, or breeding areas. If such areas are rare in a given locale, their
removal from use by wildlife may markedly reduce wildlife abundance. This is
especially important if rare, endangered, or other sensitive wildlife popula-
tions are involved. Therefore, in assessing the impact of land preemption due
to storage of coal ash or FGD sludge wastes, one must first evaluate the
kinds, extent, and value of habitat available to local wildlife resources and
the degree to which habitats are being exploited by wildlife populations.
The initial steps in quantifying the amount of habitat to be lost/ to
waste-storage facilities is to quantify the amount of wastes that will be
produced during operation of the coal-fired utility. Often, the amount of
waste produced and land requirements can be obtained from the utility. In
some instances, this information may be incomplete or one may wish to check
QUANTIFICATION
[18-26]
37
-------
utility estimates. A predominantly graphic method for estimating waste pro-
duction and land requirements for waste storage is presented below. Estimates
derived from this approach will provide approximations for the quantities in
question.
The initial step in quantifying waste production is determining the rate
of coal consumption by the operating plant (Figure 17). The rate of coal
consumption is a function of the operating capacity (rated capacity x percent
of time the plant is in operation [plant factor]), heat capacity of the coal
being consumed, and the heat rate of the plant (amount of heat required to
produce a given amount of electricity). For Figure 17, it is assumed that a
heat rate of 8930 Btu/kWe is representative of a typical coal-fired electric
generating facility. If another heat rate is to be used, the results from
Figure 17 must be multiplied by the new heat rate value and divided by 8930.
The ash produced is simply:
Amount/year = Amount/year coal burned x proportion of ash in coal (l)
The ash collected is calculated in two steps:
Amount of fly ash/year = Amount of ash/year x proportion of fly ash
in ash x percent collection efficiency (2)
Amount of aggregate/year = Amount of ash/year x proportion of
aggregate in ash (3)
Using the information in Tables 8 and 9 and Equations 1-3, one can calcu-
late the following coal consumption and ash production for the four model
2100-MWe plants, each operating at 70% of rated capacity:
Coal
(109 kg/yr)
Fly ash
(109 kg/yr)
Aggregate
(10s kg/yr)
Volume ash
col 1ected
(104 m3/yr)
Western
6.4
0.3
0.1
28
Ohio River valley
4.0
0.3
0.1
33
Texas
6.8
0.6
0.1
49
Southeastern coastal
4.0
0.4
0.1
36
The volume of ash handled can be determined from Figure 18.
A sample calculation for the Western plant is presented in Box 1.
38
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BOX 1
SAMPLE CALCULATION OF VOLUME OF ASH COLLECTED
STEP 1: Rated capacity of plant (from Table 8) = 2100 MWe.
STEP 2: Plant factor (from Table 8) = 0.7.
STEP 3: Operating capacity of plant = Step 1 x Step 2 = 0.7 x 2100 MWe
= 1470 MWe.
STEP 4: Heat value of coal to be used (from Table 8) = 8200 Btu/lb.
STEP 5: Rate of coal consumption (using Step 3 and Step 4 in Figure 17)
- 6.4 x 1Q9. kg/yr.
STEP 6: Percentage ash in coal (from Table 8) = 6.0.
STEP 7: Rate of ash production (from Equation 1) = Step 5 x Step 6
-r 100 = 4.0 x 1Q8 kg/yr.
STEP 8: % Fly ash produced (from Table 9) = 85.
STEP 9: Fly ash produced (from Equation 2) = Step 7 x Step 8 f 100
= 0.3 x lQfi kg/yr>
STEP
10:
% Fly ash collected (from Table 9) = 99.5.
STEP
11:
Fly ash collected = Step 9 x Step 10 t 100 = 0.3 x
109 ka/yr
STEP
12:
% Aggregate produced = 100 - Step 8 = 1J5.
STEP
13:
Aggregate produced and collected (from Equation 3)
= Step 7
X Step 10 T 100 = 0.1 X lo9 kg/yr.
STEP 14: Total ash collected =¦ Step 11 + Step 13 = 0.4 x 1Q9 kg.
STEP 15: Volume of ash collected (using Step 8 and Step 14 in Figure 18)
= 0.3 x 1Q6 m3/vr.
39
-------
20
16
cr
-
oc
LU
Q_
CO
O
CO
o
o
»—
Q.
Zt
ZD
CO
o
o
<
o
o
12
f
X
-L
-L
-L
16
12
8
or
LU
>-
cc
LU
Q_
CD
o>
O
O
t—
Q_
SE
=3
CO
o
O
o
o
400 800 1200 1600 2000
OPERATING CAPACITY (MWe)
2400 2800
Figure 17.
Coal Consumption as a Function of Operating Capacity of an
Electric Generating Station. A heat factor of 8930 Btu/kWe
has been assumed. The dashed line illustrates the example
in Box 1.
40
-------
400
DRY BULK DENSITY
FLY ASH: 80 lb/ft3
AGGREGATE: 165 lb/ft3
300 -
i
LU
OC
o
«x
5
200
100 -
0
- 0.4
0.3
ro
to
O
0.2 5
0.1
0.1 0.2 0.3 0.4 0.5 0.6
I06 TONS ASH COLLECTED PER YEAR
0.7
Figure 18. volume of Ash as a Function of Weight and Percentage of Fly Ash
and Aggregate. The dashed line illustrates the example in Box 1.
41
-------
FGD scrubber sludge volumes can be calculated from the data on coal
consumption rates (Figure 17), sulfur content of the coal (Table 8), S02
removal efficiency of scrubbers (Figure 19), and scrubbing reagent (Table 9).
The reagent used in the FGD scrubber influences the sulfate:sulfite (S04:S03)
ratio of the waste scrubber sludge. Limestone reagents yield sludges with
sulfate:sulfite ratios of about 8:2, lime reagents yield a ratio of about 2:8,
and lime/limestone reagents yield a ratio of about 1:1. As can be seen in
Figure 20, this sulfate:sulfite ratio influences the weight of waste solids
produced in an FGD scrubber system.
For the Western plant, the parameters of the sulfur removal system are
presented in Box 2.
BOX 2
SAMPLE INFORMATION
FOR
SULFUR EMISSIONS CONTROL
STEP 1: Sulfur content of coal (from Table 8)
= 0.48% or 0.6 Ib/Btu.
STEP 2: % S02 removal required (using Step 1
in Figure 19) = 70%.
STEP 3: Scrubbing reagent (from Table 8)
= Lime (2 SO,.:8 SO,).
42
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The weight of sludge solids can be estimated from Figures 20, 21, 22, or
23. Figure 20 is used for situations where the coal contains 2% or less of
sulfur; Figures 21, 22, and 23 are used for coals containing 2% or more sulfur
and for limestone, lime, or lime/limestone scrubbing, respectively. The
volume of sludge produced is dependent upon the proportion of dry solids in
the sludge suspension (Figure 24).
For example, at the Western plant—with 0.48% sulfur in the coal, a lime
scrubbing reagent (2 S04:8 S03), and a final dry solid percentage of 65%--the
calculations proceed as presented in Box 3.
BOX 3
SAMPLE CALCULATION OF AREA REQUIRED FOR STORAGE OF SLUDGE
STEP 1: Coal consumption (Step 5 from Box 1) = 6.4 x 1Q9 kg/yr.
STEP 2: Weight of dry solids (using Steps 1, 2, and 3 from Box 2 in
Figure 20) s 14 x 1Q3 kg per 106 kg coal combusted.
STEP 3: Total solids produced = Step 1 x Step 2 = (14 x 103)
x (6.4 x 103) t 106 = 9.0 x 1Q7 kg/yr.
STEP 4: Volume of sludge (using Step 3 in Figure 24) = 1.0 x 1Q3 m3 per
106 kg dry solids.
STEP 5: Volume of sludge produced annually = Step 3 x Step 4
= (9.0 x 107) x (l.o x 103) t 106 = 9.0 x 1Q4 m3/yr.
STEP 6: Minimum area required for storage (from Figure 25 using depth
of 9.1 m and Step 5) = 9.0 x 103 m2/yr = 0.9 ha/yr.
The minimum area needed to handle this sludge can be obtained from Fig-
ure 25. If the ash at this site were impounded with the sludge, the area
could also be estimated from the volume produced by using Figure 24 and
Step 15 in Box 1.
43
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POUNDS SULFUR PER 10s Btu
I'll I I I I 1 I 1 I
0 4 8 12 16 20
POUNDS S02 PRODUCED PER 10s Btu
Figure 19. Percentage S02 Removal Required to Meet USEPA
Emissions Standards. The dashed line illus-
trates the example in Box 2.
44
-------
1.0 1.5 2.0
% SULFUR IN COAL
Figure 20. Amount of FGD Sludge Solids Produced When the Sulfur Content
of Coal is < 2% as a Function of Coal Sulfur Content and
Percent Removal of S02 from the Flue Gas. The dashed line
illustrates the example in Box 3.
45
-------
cn
z
o
o
-
cc
Q
CO
o
to
o
80 S04 : 20 SO3
LIMESTONE SCRUBBING
2 70 -
1
±
190 q
CO
O
o
<
o
o
0
X
o
ce
UJ
Q.
Ui
O
Q
CO
>-
CC
Q
O
ro
O
70
2.5
3.0
%
3.5
SULFUR
4.0
IN COAL
4.5
5.0
Figure 21. Amount of FGD Sludge Solids Produced for Limestone Scrubbing
and Coal Sulfur Contents > 2% as a Function of Sulfur Content
of the Coa"! and Percent Removal of S02 from the Flue Gas.
46
-------
230
o
LlJ
ZD
CO
z
o
o
190
o
o
en
150
(O
O
cc
UJ
Q_
ZD
—I
>-
C£
CD
o>
Q
110
ro
2 70
230
190
CO
o
c_>
150
<*
o
<_>
o
no
to
O
cc
UJ
CL
CO
>-
s
70
2.5 3.0 3.5 4.0 4.5 5.0
% SULFUR IN COAL
Figure 22. Amount of FGD Sludge Solids Produced for Lime Scrubbing and
Coal Sulfur Contents > 2% as a Function of Coal Sulfur Content
and Percent Removal of S02 from the Flue Gas.
-------
%
3.5 4.0
SULFUR IN COAL
Figure 23.
Amount of FGD Sludge Solids Produced from Combined Lime/
Limestone Scrubbing and Coal Sulfur Contents > 2% as a
Function of Sulfur Content and Percent Removal of SO2
from the Flue Gas.
48
-------
4.0 -
3.0 -
2.0 -
1.0 -
SPECIFIC GRAVITY
OF DRY SOLIDS
IS 2.4
VOLUME
OF
WATER
CO
o
—1
o
CO
>-
ce
Q
£
id
o
or
LlI
Q_
PO
PO
O
0.3 f
VOLUME OF DRY SOLIDS
' ¦ ' i i I i
20 40 60 80
% DRY SOLIDS IN SLURRY
Figure 24. Volume of FGD Sludge as a Function of
the Percentage of Dry Solids. The
dashed lines with arrows illustrate
the examples in Boxes 3 and 4.
49
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VOLUME tro6 M3)
VOLUME (ACRE-FEET)
Figure 25. Acreage Required to Hold Waste as a Function of Volume of
Waste and Depth of Storage. The dashed line illustrates
the example in Box 3.
50
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Impounded wastes require an additional preemption of land by the berm or
dike surrounding the storage area. If more accurate information is not avail-
able, one may use an approach for estimating area under the dike as illus-
trated in Figure 26. This figure presents a schematic of the distance beyond
the waste covered by a dike with a 5:1 external slope and 3:1 internal slope,
i.e., 3 horizontal meters for each vertical meter. For this estimate, it was
assumed that waste depth was 9.1 m, freeboard (height from waste surface to
top of dike) was 1.5 m, and a 5-m wide roadway ran along the top of the dike.
Under these assumptions, simple geometric calculations yield a dike basal
width of 65.5 m. In adding the dike width to area preempted by waste alone, a
correction for displacement by the internal slope can be estimated as half the
horizontal distance from the contact points of the dike and the substrate to
that of the dike and the waste surface (15 m in our example). The total area
preempted by the berm can then be approximated as width of dike times length
of dike required. In the example, 50.5 m is the width of the dike (65.5 m)
minus the correction for displacement of waste by the dike (15 m). In some
areas (particularly urban areas), a 30-m buffer area may also be required
around the site (Duvel et al. 1979). Thus, for the Western model site, the
minimum amount of land for the storage impoundment would be about 36 ha for
sludge and 14 ha for berm, or 50 ha in order to hold the FGD waste from 40
years of plant operation.
WASTE SURFACE
GROUfi
-65.5m
SUBSTRATE
Figure 26. Schematic of a Generalized Impoundment Dike
for the Western Plant.
51
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The area set aside for storage of 40-years' production of waste at each
of the model plants is as follows:
Area for storage of
40-years' waste
production
Model plant
hectares
acres
Western
53
130
Ohio River valley
670
1,650
Texas
730
1,800
Southeastern coastal
730
1,800
IMPACT ANALYSIS [43]
Over the past several years, the U.S. Fish and Wildlife Service has been
developing a methodology for evaluating the value of land as wildlife habitat,
i.e., "The Habitat Evaluation Procedure" (U.S. Fish Wildl. Serv. 1980). These
procedures provide the wildlife biologist with a means for comparing the value
of different habitats that may be affected by development of a waste-storage
facility. Galvin (1979) provides a collection of information on wildlife and
their habitat requirements that can be useful in estimating habitat value.
Additionally, it is necessary to know the availability of that habitat for use
by wildlife populations. If a habitat is rare and of high wildlife value, it
is less desirable as a waste-storage site than is a more common habitat of
moderate value. The Soil Conservation Service, Bureau of Land Management, and
state wildlife officials may serve as sources of information on habitat dis-
tribution in the region of concern. In the end, the wildlife biologists must
rely greatly upon their own experience and knowledge to evaluate the potential
for adverse impacts from developing a waste-storage facility at a given site.
Preemption of land at the four model facilities will result in an incre-
mental loss of potential wildlife habitat. Therefore, there will be potential
for decrease in those species utilizing this habitat. Even after reclamation,
the site will not be as valuable for wildlife habitat for at least several
decades. At the Western site, the habitat to be lost is of relatively high
value to wildlife, but is only a small fraction of the habitat available in
the region. At the Ohio River site, more area will be lost and, because the
area is already highly industrialized, this could be of importance to several
populations of wildlife. However, bald eagles and Virginia big-eared bats
would not be directly impacted by these habitat losses. There will be a
reduction in red wolf habitat (open woodlands) at the Texas site, which'could
be detrimental to local populations. The Southeastern coastal facility will
52
-------
use as much land as the Texas facility, but the habitat to be preempted does
not support populations of wildlife that are as sensitive as the red wolf. Of
all the sites, the Texas facility is most likely to threaten the survival of a
wildlife population.
INFORMATION REQUIREMENTS AND SOURCES
The following is a list of information required to carry out an analysis of
wildlife habitat loss as discussed in this chapter. The most likely sources
of this information are also identified.
Information required
Sources
Power plant operating characteristics
and coal type
Facility operator
Design of storage facility
Facility operator
Location and area of proposed site
Facility operator
Site visit
Estimated from quanti-
ties of waste to be
produced
Habitat type
Facility operator
Literature
Site visit
U.S. Fish and Wildlife
Service
Other federal agencies
Local university
biologist
Important wildlife resources
Facility operator
Literature
Site visit
U.S. Fish and Wildlife
Service
Other federal agencies
Local university
biologist
53
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MITI6ATIVE MEASURES
The loss of potential wildlife habitat is unavoidable for any waste-
storage facility. However, some mitigation of impacts is possible. The four
methods most likely to be used at a waste-storage site are:
• Maximizing the density of the waste so that less land is required
per unit volume of waste.
• Increasing the depth of stored waste so that less area is used.
• Revegetating the site as it is filled.
• Protecting from development an area of equivalent or higher wildlife
value in compensation for preempting land for waste storage.
• Upgrading of nearby habitat to enhance value to wildlife.
54
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Chapter 6
Water Consumption
POTENTIAL IMPACTS
[73-75]
Numerous water bodies (lakes, ponds, reservoirs, and rivers) have com-
peting water users; the addition of a coal-fired power plant or a change in
the processing of combustion waste products could place an additional demand
on water resources managed for fish and wildlife. Changes that occur in eco-
systems from which water is drawn are directly related to water loss. The
severity of these effects is modified by season of the year and rate and
frequency of drawdown associated with consumptive water use. Changes in both
terrestrial and aquatic ecosystems will be greater where the percentage change
from baseline characteristics is greatest; this is more likely in small water-
sheds or in more arid areas where the amount of available water is low.
A reduction in total volume of water in aquatic systems can stress aquat-
ic biota by causing changes in production, loss of habitat, and changes in
species composition. Organisms can become concentrated, thereby increasing
both competition for resources and interactions with other species. These
effects can be important if the littoral zone is reduced or eliminated,
because it is this zone in which forage grows and becomes available to support
the many interrelated organisms within the ecosystem.
Potential impacts from impingement or entrainment are generally small to
immeasurable due to the low flows (<10 cfs) required to support waste-handling
operations.
QUANTIFICATION
Estimating Consumptive Use of Water
The volume of water required for solid-waste disposal will depend on the
specific waste-handling procedure employed. Using Figure 24, the amount of
water required in waste handling can be estimated from the amount of solids
55
-------
and the percentage of water in the waste stream. There will be evaporative
loss of water in the scrubbers; however, no attempt has been made to quantify
this loss.
Consumptive Use of Water by Model Plants
Western plant. The lime scrubbing process generates a slurry of 85%
water by weight and requires 52 ha-m (420 acre-ft) of water per year supplied
from the Powder River. The slurry is thickened to 65% water by weight, and
water from the thickening process is recycled to the scrubbing system. Thus,
32 ha-m (280 acre-ft) of water are recycled per year, and 20 ha-m (140 acre-
ft) of water are required per year. However, based on leachate seepage esti-
mates (p. 80), 9 ha-m/yr (70 acre-ft/yr) of the 20 ha-m/yr (140 acre-ft/yr)
are reintroduced to the Powder River water system and the loss from the system
is 9 ha-m/yr (70 acre-ft/yr). The average precipitation falling on the pond
surface inside the berm area--which is not reintroduced to the hydrological
system--is 38 cm/yr on 36 ha (98 acres) or 14 ha-m/yr (130 acre-ft/yr).
Adding 11 ha-m/yr loss from evaporation, the total water loss is 25 ha-m/yr
(200 acre-ft). A sample calculation is presented in Box 4.
Ohio River valley plant. The lime scrubbing process generates a slurry
of 85% water by weight and requires 360 ha-m (2880 acre-ft) of water per year.
Excess water from the storage pond is not recycled to the scrubbing system.
However, based on leachate seepage estimates (p. 80), 80 ha-m/yr (650 acre-
ft/yr) of the 360 ha-m/yr are reintroduced to the Ohio River system and
750 ha-m/yr (6100 acre-ft/yr) minus 540 ha-m/yr (4360 acre-ft/yr) of precipi-
tation are reintroduced by surface discharges. Therefore, net consumptive
water use is 360 ha-m/yr minus (80 ha-m/yr plus 210 ha-m/yr) or 70 ha-m/yr
(570 acre-ft/yr).
Texas plant. Tlie limestone scrubbing process generates a slurry of 85%
water by weight and requires 120 ha-ra/yr (95G acre-ft/yr) of water. Water
from mechanically thickened sludge (98 ha-m/yr or 790 acre-ft/yr) is not
recycled to the limestone scrubbing system but is discharged to a nearby
stream. The average net consumptive water requirement for the scrubbing
system is 20 ha-m/yr (160 acre-ft/yr).
Southeastern coastal plant. The limestone scrubbing process generates a
slurry of 85% water by weight and requires 160 ha-m (1260 acre-ft) of water
per year. Water from the storage pond underdrain system is recycled to the
limestone scrubbing system. Assuming that seepage discharge from the pond is
limited by the hydraulic conductivity of the ash-sludge mixture, which is
assumed to be 1 x 10-6 cm/s, through approximately 570 surface hectares
(1400 acres), the equivalent of all leachate seepage from the initial 85%
water by weight and the final 35% water by weight is recycled (150 ha-m or
1200 acre-ft of water per year) to the limestone scrubbing system. The total
water withdrawn from the hydrological system is 43 ha-m (350 acre-ft) per
year. This water is obtained from an onsite well because of the low flow
(950 ha-m/yr) within the nearby stream.
56
-------
BOX 4
SAMPLE CALCULATION OF WATER USE AT THE WESTERN PLANT
STEP 1: Scrubber solids produced (from Step 3, Box 3) = 9.0 x 1Q7 kg/yr.
STEP 2: % Solids in initial slurry (from p. 29) = 15%.
STEP 3: Volume of water in initial slurry (using Step 2 in Figure 24)
= 5.8 x 1Q3 m3 per 1Q6 kg dry solids.
STEP 4: Volume of water per year in initial slurry = Step 1 x Step 3
= (9.0 x 107) x (5.8 x lo3) t 106 = 5.2 x 10s m3/yr
= 52 ha-m/yr.
STEP 5: % Solids in dewatered sludge (from Table 11) = 35%.
STEP 6: Volume of water in dewatered sludge (using Step 5 in Figure 24)
= 2.2 x 1Q3 m2 per 106 kg dry solids.
STEP 7: Volume of water per year in dewatered sludge = Step 1 x Step 6
= (9.0 x 107) x (2.2 x 103) ^ 106 = 2.0 x 105 m3/yr
= 20 ha-m/yr.
STEP 8: Volume of water recycled from dewatering = Step 4 - Step 7
= 52 - 20 = 32 ha-m/yr.
STEP 9: Volume of water in seepage (from p. 80) = 9 ha-m/yr.
STEP 10: Volume of water lost from hydrologic system = Step 7 - Step 9
= 20 - 9 = 11 ha-m/yr.
STEP 11: Minimum area for rainfall caught in pond (from p. 51) = 36 ha.
STEP 12: Average annual precipitation = 0.38 m/yr.
STEP 13: Volume precipitation caught in pond = Step 12 x Step 11
= 0.38 x 36 = 14 ha-m/yr.
STEP 14: Total water loss to hydrologic system = Step 10 + Step 13
= 11 + 14 = 25 ha-m/yr.
57
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IMPACT ANALYSIS
[73-75]
Evaluating Consumptive Use of Water
Impact analysis is based on direct removal of water from an aquatic
ecosystem for handling of combustion and emission-abatement wastes. If cumula-
tive demands of industrial, utility, municipal, and agricultural consumptive
water are substantial, regional analysis of consumptive use is necessary.
Piecemeal consideration may be misleading, and on a case-by-case basis one may
dismiss impacts as negligible although the cumulative effect to aquatic re-
sources may be marked.
In assessing the significance of water withdrawal from an aquatic habi-
tat, the biologist must rely heavily upon his own knowledge of the habitat
requirements of populations inhabiting the source of makeup waters. Impacts
can be evaluated by determining the habitat alterations that will occur due to
the continuous withdrawal of water. The Western Energy and Land Use Team of
the U.S. Fish and Wildlife Service is developing instream flow strategies for
many states. As part of this effort, weighted criteria are used to assess the
impacts of altered stream-flow regimes on a stream habitat (Bovee and Coch-
nauer 1977). This information base can be used to evaluate the impacts of
withdrawing water from stream ecosystems. For lake or pond systems, the
habitat alteration due to lowering the water level can be estimated from
knowledge of the system's morphometry. The significance of habitat attenu-
ation to the affected fishery resources can be evaluated by determining if the
habitat requirements of the fish populations are compatible with the expected
habitat changes.
Impact of Consumptive Use of Water by Model Plants
Consumptive use of water for waste handling at the model plants is as
f o 1]ows:
Consumptive use of water
Model plant location
ha-m/yr
acre-ft/yr
Wyomi ng
25
200
Ohio
70
570
Texas
20
160
North Carolina
43
350
Consumptive use at the Wyoming storage site, along with other consumptive uses
of the power plant, puts increased pressure on already scarce water resources
of the area. Removal of water from the Powder River during periods of low
flow may result in adverse impacts to fish and wildlife. However, consumptive
58
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use of water at the storage site should not substantially alter the flow
regime of the Powder River (ca. 2.5 x 104 ha-m/yr) or the available aquatic
habitat. Thus, there should be little impact to fish and wildlife resources.
Stream flows at the Ohio and Texas plants are ca. 9.5 x 106 ha-m/yr and
9500 ha-m/yr, respectively. Consumptive water use for waste-handling pro-
cedures at these plants puts little pressure on water resources of the areas.
Although dilution rates for downstream discharges could be lessened, this is
not likely to be of major concern because both plants withdraw less than 0.2%
of the stream flow. Fish and wildlife should not be impacted adversely.
The North Carolina plant obtains water from a well, and fisheries re-
sources will not be impacted.
INFORMATION REQUIREMENTS AND SOURCES
The following is a list of information required to carry out an analysis of
water consumption as discussed in this chapter. The most likely sources of
this information are also identified.
Information required
Sources
Procedures for handling wastes
Facility operator
Storage site operation and design
Facility operator
Site-specific aquatic habitat data, including
water quality and quantity and biological
assemblages
Site visit
Facility operator
U.S. Army Corps of
Engineers
U.S. Fish and Wildlife
Service
Local Public Health
Service
59
-------
MITIGATIVE MEASURES
The volume of water required for solid-waste disposal will depend on the
specific waste-handling procedure employed. Thickening and dewatering (by
means of settling ponds, thickeners, vacuum filters, and centrifuges) are used
on the scrubber bleed stream to reduce the water content. Increasing the
sulfate content of the sludge (e.g., by forced oxidation) improves the de-
watering potential of the wastes. Pipeline transport of wastes to basins will
require large volumes of water if no recycling is practiced. After the solids
have settled, the supernatant water may be discharged to surface waters,
evaporated, or recycled. Consumptive use is greatest if dewatering is by
evaporation, least if the supernatant liquid is discharged to surface waters,
and intermediate if the water is recycled. Recycling can reduce the amount of
water consumed by an order of magnitude over dewatering by evaporation. These
options for reducing consumptive water use are particularly important where
water resources are scarce, e.g., the arid West. Additionally, if impacts to
aquatic ecosystems due to consumptive water use during low flow periods are
projected to be substantial, water probably can be removed during high flow
periods and stored in a reservoir. This would result in less impact to the
aquatic ecosystem, although more water would be required to take into account
evaporation from the reservoir.
60
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Chapter 7
Runoff and Erosion
POTENTIAL IMPACTS
[44-50]
Constituents of ash and FGD sludge wastes can be dispersed from the
storage site into terrestrial and aquatic environments through runoff. Rain-
drop impact and the overland flow of water (i.e., runoff) are processes that
result in water erosion of both suspended and dissolved solids. Although
raindrop impact contributes to displacement of erodible materials, runoff is
the principal transport mechanism of the erosion-sedimentation processes
induced by water.
There are two aspects of waste storage that may be affected by erosion:
the waste material itself and co\/4r or containment materials used to confine
the wastes. The cover and containment materials are usually composed of
disturbed and perhaps compacted soils and subsoils. The principles of erosion
that have been elucidated over the past several decades are derived from the
behavior of undisturbed soils. In the discussion of erosion presented here,
these principles are applied to the erosion of wastes and cover on containment
materials. These materials do not behave exactly like true soils, but the
general principles of erosion are still valid.
The potential for transport of coal combustion wastes into the environ-
ment through runoff is a function of (1) the method of ash and FGD sludge
storage, (2) local climatic conditions, (3) topography, and (4) waste or cover
material characteristics. Brief intense rainfalls, sparse vegetative cover,
low infiltration capacity, and location of a storage facility in hilly topog-
raphy will promote erosion.
QUANTIFICATION [44-50]
At sites where water erosion is a critical issue, the investigator may
elect to use the Universal Soil Loss Equation (USLE) for predicting erosion
potential. The equation is usually adequate for characterizing the water-
61
-------
erosion potential for small areas such as waste-storage sites (Wischmeier and
Smith 1978) because it can be used to estimate the sediment generated and
displaced from a given area by sheet and rill erosion during a future period
of time. As presented here, the USLE should not be interpreted as a precise
prediction of erosion loss. Many of the factors influencing erosion have been
generalized to obtain a tool that can be readily used without a background in
soil science. The USLE is expressed as:
Erosion Loss = R x K x LS x C x P (4)
The soil model from which the USLE was derived can be extrapolated to
other materials such as berm spoils, coal ash, and FGD sludge. Thus, we have
used this equation as a means of estimating erodibility of coal combustion
waste-storage areas. However, the properties of combustion wastes and soils
are different due to differing origins of the materials, and, although the
factors that influence soil erosion can generally be said to affect the ero-
sion of other materials, the magnitude of the effects may not be precisely the
same.
Rainfall Factors (R)
Rainfall factors or R values, which represent the integration of raindrop
effect and the amount of runoff, have been calculated for numerous areas
throughout the contiguous United States. They are the basis for the iso-
erodent (lines of equal R values) delineations shown in Figure 27. The
R value for a given site can be established by interpolation between two adja-
cent isoerodents. For example, R values for the southern third of Illinois
range between 200 and 250; the value for a site equidistant between the iso-
erodents is 225. The isoerodents are based on rainfall characteristics, and
empirical evidence shows that R values for areas where significant runoff
results from ice and snowmelt must be adjusted by adding 1.5 times the rain-
fall equivalent of the annual snowfall. For example, given an R value of 20
in western Colorado and precipitation from 1 December through 31 March equiva-
lent to 12 inches of water: R = 1.5 (12) + 20, or 38.
Erodibility Factors (K)
Tables of experimentally determined erodibility factors or K values are
available from state SCS offices for many specific soils. However, such
values may or may not be appropriate for subsurface and other materials ex-
posed during site development and management operations. Given the textural
composition, organic matter content, structural characteristics, and perme-
ability of the materials to be exposed, the K values can be apprcpximated by
use of the nomograph presented as Figure 28. Much of the necessary informa-
tion should be obtainable from the utility. Other information can usually be
extracted or approximated from published soil surveys or other literature, but
analysis of materials will probably be necessary in some instances. For dry
coal ash, K is approximately 0.85--ass.uming particle size distribution of a
clay, no organic matter, very fine granular structure, and very slow perme-
ability.
62
-------
en
OJ>
Figure 27. Average Annual Values of the Rainfall Erosion Index. From Wischmeier and Smith (1978).
-------
Figure 28. The Soil-Erodibility Nomograph. From Wischmeier and Smith (1978).
-------
Topographic Factors (LS)
Topographic factors (LS) are a combination of slope length (L) and slope
gradient (S) factors. The L factor is the ratio of soil loss from the field
slope length of the area in question to that from a 72.6-ft slope length under
identical conditions. The S factor is the ratio of the soil loss from a field
slope gradient to that from a 9% slope under otherwise identical conditions.
Topographic factors are presented in Figure 29. To use the figure, identify a
field-measured length of slope on the horizontal axis; move vertically to
intercept the appropriate percent slope measured in the field; then read the
LS value on scale at the left. For example, the LS value for a 200-ft slope
with a 14% gradient is about three. The LS values derived in this manner are
appropriate only for uniform slopes.
Cover Factors (C)
Cover factors (C) represent the effects of vegetative cover and land-
management variables (including effects associated with agricultural prac-
tices). In the event that all aboveground vegetation and plant roots are
removed, as in the case of an unrevegetated waste-storage pile, C for the
denuded area will be equal to one. Numerous measures can be initiated to
reduce the C value, including applications of various types of mulch. Some
examples of the effects of mulching are illustrated in Table 12.
Support Practice Factors (P)
The support practice factor (P) is the ratio of soil loss with a support
practice (contouring, strip cropping, or terraining) to that with straight-row
farming up and down the slope. P factors for open waste dumps will usually be
equal to one, and thus will not affect estimates based on other USLE factors.
P factors for managed waste dumps can be less. Terracing could be used to
reduce LS, but the erosion-reducing effects due to terracing would be ac-
counted for in the determinations of LS values.
IMPACT ANALYSIS [44-50]
Evaluating Erosion Potential
Evaluating erosion potential is a prerequisite to assessing the potential
for dispersal of waste constituents from a given waste-storage site. Although
it is unlikely that information will be available describing the physical
characteristics of the coal ash or scrubber sludge to be produced by a pro-
posed coal-burning powerplant, data from the literature (e.g., Duvel et al.
1979; GAI Consultants, Inc. 1979; and Page et al. 1979) can be used to ade-
quately describe the waste materials. When these data are coupled with design
details of the proposed waste-storage facility (e.g., method of waste deposi-
tion, length and steepness of slopes) and information describing local topo-
graphy and climatic conditions, the USLE can then be used to estimate the
potential for erosion of berms and wastes from the proposed facility.
65
-------
SLOPE LENGTH (FEET)
Figure 29. Slope Effect Chart. The dotted line illustrates the example
on page 65. From Wischmeier and Smith (1978).
-------
Table 12. Mulch Factors and Length Limits for Construction Slopes3
Type of mulch
Mulch
rate
(103 kg/ha)
Land
slope
(%)
Cover
factor
(C)
Length
1imitb
(m)
None
0
all
1.0
-
Straw or hay
2.2
1-5
0.20
60
(tied down by anchoring and
2.2
6-10
0.20
30
tacking equipment)c
3.3
1-5
0.12
90
3.3
6-10
0.12
45
4.4
1-5
0.06
120
4.4
6-10
0.06
60
4.4
11-15
0.07
45
4.4
16-20
0.11
30
4.4
21-25
0.14
22
4.4
26-33
0.17
15
4.4
34-50
0.20
10
Crushed stone
297.
<16
0.05
60
(k to lh inches)
297.
16-20
0.05
45
297.
21-33
0.05
30
297.
34-50
0.05
22
528.
<21
0.02
90
528.
21-33
0.02
60
528.
34-50
0.02
45
Wood chips
15.
<16
0.08
22
15.
16-20
0.08
15
26.
<16
0.05
45
26.
16-20
0.05
30
26.
21-33
0.05
22
55.
<16
0.02
60
55.
16-20
0.02
45
55.
21-33
0.02
30
55.
34-50
0.02
22
Adapted from Meyer and Parts (1976). Originally developed by an inter-
agency workshop group on the basis of field experience and limited
bresearch data.
Maximum slope length for which the specified mulch rate is considered
effective. When this limit is exceeded, either a higher application
rate or mechanical shortening of the effective slope length is required.
When the straw or hay mulch is not anchored to the soil, C values on
moderate or steep slopes of soils having K values greater than 0.30
should be taken at double the values given in this table.
67
-------
Careful consideration should also be given to how local soils used in the
construction of dikes or runoff channels could be affected by water erosion.
Soils containing a high proportion of clay will have low infiltration capaci-
ties, which will enhance runoff. Soil survey maps with suitable interpreta-
tions will provide information for specific sites, including erosion poten-
tial. These surveys may identify plants suitable for establishing vegetation
cover with a minimum of soil treatment. Many such surveys are available from
local Soil Conservation Service offices. In addition, onsite soil investiga-
tions before and during operations are generally needed to supplement the soil
survey.
The USLE can be used to estimate the amounts of water erosion expected
from a waste-storage facility. However, the biologist must determine whether
a given level of erosion will be hazardous to the biota of adjacent areas or
eventually undermine the integrity of the storage facility.
Impact of Runoff Dispersal from the Model Storage Sites
In the Wyoming, Ohio, and North Carolina model storage sites, scrubber
sludge or the combination of scrubber sludge and coal ash are disposed of in
diked storage ponds. For each of these storage facilities, the length-slope
factor of the USLE is zero for the storage area; therefore, erosion loss per
unit area per unit time is zero. Potential for soil loss from the storage
pond dikes can be minimized by proper design to preserve dike integrity.
At the Texas model plant, runoff dispersal of the wastes could occur
without proper management of the heaped-landfill. The rainfall and runoff
factor (R) of the USLE is high (Figure 27). The soil erodibility factor (K)
is approximately 0.85 for ash and 0.68 for Tuckerman loam soil cover (Fig-
ure 28)--assuming that the soil has blocky structure, is very slowly per-
meable, and is composed of 0% organic matter, 80% fine sand and silt, and 5%
sand. The vegetation cover (C) and support practice (P) factors can be as-
sumed to be one. As can be seen from the calculation of USLE in Box 5, antic-
ipated erosion loss from the landfill embankments is high. The landfill will
have to be properly revegetated to reduce C, and terraced or otherwise con-
toured to reduce P. Design of the embankment slope could be modified to
reduce LS but this would require increasing the areal extent of the landfill.
68
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BOX 5
SAMPLE CALCULATION OF RUNOFF DISPERSAL AT THE TEXAS PLANT
STEP 1: Rainfall and runoff factor (R): Using Figure 27, R = 400.
STEP 2: Soil erodibility index (K): Using Figure 28 for Tuckerman loam
(a soil with blocky structure, very slow permeability, and
0% organic matter, 80% fine sand and silt, and 5% sand),
K = 0.68.
STEP 3: Topographic factor (LS): Using length of slope (76.9 ft) and
percent slope (5:1 or 20%) in Figure 29, LS = 3.6.
STEP 4: Cover factor (C): For an unrevegetated slope, C = 1.
STEP 5: Support factor (P): Assumed for this example, P = 1.
STEP 6: Erosion loss (A): Using Equation 4, A = R x K x LS x C x P
= 400 x 0.68 x 3.6 x 1 x l = 979.2 tons/acre/yr.
69
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INFORMATION REQUIREMENTS AND SOURCES
The following is a list of information required to carry out an analysis of
runoff and erosion as discussed in this chapter. The most likely sources of
this information are also identified.
Information required
Sources
Characteristics of soils:
Soil maps
Detailed soil descriptions
Land-use capabilities and limitations
Soil management guidelines
Descriptions of local climate, geology,
and topography
Field offices of Soil
Conservation Service
Local universities
Precipitation and evaporation potential
Local weather reporter
Natl. Weather Service
Facility operator
Design of the storage site
Facility operator
Properties of the waste
Facility operator
MITIGATIVE MEASURES [111]
In general, mitigation of erosion involves manipulating the parameters of the
Universal Soil Loss Equation in order to reduce the rate of soil loss.
Storage-Site Design
Various structures can be designed to control surface runoff from waste
-storage sites, including:
• Contour terraces, at intervals normal for sloping sur-
faces, to increase surface storage capacity
70
-------
• Storage or siltation ponds to increase surface storage
capacity
• Ditches, earthern dikes, piping, hay bales to temporarily
divert and spread runoff
• Permanent structures to collect and channelize runoff
• Permanent check dams, at intervals within the runoff-
collection channel, to control gully or channel erosion
and depositions of sediment downslope
The kinds and extent of structures used for surface runoff control will
be dependent on site-specific considerations. Control measures will also vary
according to the storage method.
Physical Methods
Surface runoff from waste-storage sites can be reduced through the use of
the following techniques:
• Tillage of waste surfaces to increase roughness and clod-
diness of exposed materials, thereby increasing rainfall
infiItration.
• Emplacement of organic mulches crimped into surface
materials by discing.
• Applications of thin layers of coarse gravel, country
rock, or crushed stone.
Chemical Methods
The promotion of surface crusting by chemical stabilizers is effective
for controlling water erosion. Surface crusts absorb the energy of raindrop
impact, preventing the detachment of surface particles. However, these crusts
also decrease rainfall infiltration and enhance surface runoff. Because of
the binding effect of the stabilizers, the runoff would have a lower particu-
late load. Several available chemicals have been shown to be cost effective
in stabilizing mill tailings under laboratory conditions (Qean et al. 1974).
Vegetative Methods
The establishment of a self-perpetuating vegetative coyer on a waste-
storage site is one of the more cost~effective and aesthetically desirable
methods for controlling water erosion, Vegetation obstructs the flow and
tends to reduce the velocity of surface runoff, thus reducing the erosive
force of the runoff. However, opportunities for establishing vegetation prior
to final reclamation of a given waste-storage area will be dependent on site-
specific conditions as well as the storage method.
71
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Chapter 8
Seepage of Leachate
POTENTIAL IMPACTS
[50-54]
Vertical and lateral seepage of leachate can occur from ash and sludge
waste-storage sites, particularly where the waste material is deposited as a
slurry, The major impact of seepage is addition of potentially toxic leachate
waste constituents to groundwater and soil. Contamination of groundwater can
result in eventual contamination of fish and wildlife water sources.
Seepage and transport of potentially toxic elements and ions from storage
sites are influenced by a number of factors (Dvorak et al. 1978; Duvel et al.
1979). The most important are: physicochemical properties of ash and/or
sludge waste and surrounding substrate (including permeability, pH, cation
exchange capacity, and trace element composition) and rainfall zone.
Physicochemical Properties of Waste Materials
and Surrounding Substrate
Permeability. Permeability of ash and sludge wastes and storage-site
substrates is one of the most important parameters influencing leachate seep-
age from storage sites (Duvel etal. 1979). Hydraulic conductivities for
different soil types and waste materials are presented in Figure 30. Hydrau-
lic conductivity (k) is a constant property of a material and is one of the
parameters determining permeability of that material. Permeability is a
direct function of k. Hydraulic conductivity is expressed in units of length
per time (e.g., cm/s).
Stratification of soils and wastes can also markedly affect permeability
by creating layers of differing compaction. Other factors affecting perme-
ability are density, trapped air pockets, and dissolved salt content of the
leachate--all of which are inversely correlated with bulk water movement
(Duvel et al. 1979). Contamination of groundwater is related to the perme-
ability of the impoundment material; in general, the permeability of such
material increases in the order: granite < shale < sandstone < soil < sand.
73
-------
FT/YR
GAL/DAY/FT'
10® I07 10®
10® I04 I03 I02
10
I0~' I0~2 10 3
1
I06
1
1 1
I05 I04
1 1
1
I03
1
1
I02
1
o -
i
10"'
1 1
1 1 1
I0"2 I0"3 I0"4
1 1 1
CM/S
10'
10
I
10"' I0~2 I0"3 I0*4 I0"5 I0~6
I0'7 I0"8 I0"9
SOIL
TEXTURE
TYPE
CLEAN
GRAVEL
CLEAN SANDS}
CLEAN SAND AND
GRAVEL MIXTURES
VERY FINE SANDS;
SILTS; SAND, SILT AND
CLAY MIXTURES
UNWEATHERED
CLAYS
DRAINAGE
CHARAC-
TERISTICS
GOOD
TO
FAIR
POOR
IMPERVIOUS
COMPACTED
FLY ASH
FGD SLUDGE
»-H
UNTREATED TREATED
Figure 30. Saturated Hydraulic Conductivities for Different Soil Types
at Unit Gradients. Modified from Duvel et al. (1979); com-
pacted fly ash data based on Frascino and Vail (1976).
£H. Soil pH influences movement of leachate seepage. The solubilities
of most trace elements in water tend to decrease as pH is increased (Frascino
and Vail 1976). The pH of most ash- and sludge-pond leachates will be neutral
or alkaline. In general, trace-element-toxicity effects should be of more
concern when the absorbing medium (soil) and transporting medium (pond leach-
ates) are acidic rather than neutral to alkaline. However, elements forming
anions (e.g., boron and arsenic) may be as mobile under alkaline as under
acidic conditions.
Cation exchange capacity. Cation exchange capacity of a soil influences
transport of solutes. In general, the higher the clay content and organic
matter of a soil, the greater is its cation exchange capacity (Table 13). A
high clay content in a soil tends to bind cations in seepage and to reduce the
percentage of cations entering groundwater. Such retention in the soil allows
a greater concentration source for eventual uptake by vegetation. If the
soils are sandy, there is a tendency for rainfall to leach away the cations
from the root zone, but this increases the chances for groundwater contamina-
tion.
74
-------
Table 13. Factors Affecting Soil Cation
Exchange Capacity (CEC)a
Soil factor
Relative CEC
Texture
Sand
Loam
Clay
Organic content
Low
High
Clay type
Hydrous oxides
Kaolinite
Chlorite
Hydrous micas
Montmorillonite
Vermiculite
Low
Moderate
High
Low
High
Low
Low
Low
Low
High
High
(
4 meq/100 g)
8 meq/100 g)
( 30 meq/100 g)
( 30 meq/100 g)
(100 meq/100 g)
(150 meq/100 g)
Based on data in Brady (1974).
Trace-element composition. The background levels of trace elements in
soils are inportant in influencing the potential for toxic effects from waste
leachate. There are regions of the country wtiere high concentrations of
certain elements such as selenium and Hiolybdenum occur locally (see Dvorak
et al. 1973). In these regions, addition to the soil of these e^ments from
waste seepage over the long term may aggravate the potential for adverse
effects to wildlife. Also, incoming seepage may displace potentially toxic
ions (e.g., aluminum) from soil and transport them to groundwater.
Rainfall Zone
The amount of rainfall entering a waste-storage site and its environs
markedly affects the potential for adverse effects from the waste at sites
where the waste-storage impoundments are not lined. If the average annual
rainfall is low, seepage from the waste-storage site will tend to remain in
the upper layers of the soil, thus increasing the chances for uptake by vege-
tation; however, seepage to groundwater will be low, depending on the depth at
which the water table occurs. In zones of high rainfall, ionic constituents
of waste will tend to be leached rapidly to groundwater, particularly where
the substrate is sandy or otherwise relatively permeable. High rainfall will
also tend to move dissolved material laterally into the soil.
75
-------
Figure 31. Average Annual Precipitation in the United States. From Geraghty et al. (1973)
(reprinted with permission from Water Information Center, Inc., Syosset, NY,
Copyright 1973).
-------
Figure 32. Average Net Precipitation in the United States. Figures represent difference
in inches between precipitation and evaporation. From Duvel et al. (1979).
-------
Average annual and net precipitation (difference in inches between pre-
cipitation and evaporation) tend to increase west to east across the United
States, excluding coastal areas (Figures 31 and 32). Average net precipita-
tion values in the eastern United States are positive, whereas in most of the
western United States values are negative. In general, leachate quantities
are likely to be greater in the eastern part of the country. However, in the
arid West where net precipitation is negative, seepage of ions could lead to
soil salinization as the ions are carried up into the plant rooting zone.
QUANTIFICATION AND IMPACT ANALYSIS [54-59]
Quantity, composition, and movement (seepage) of leachate are influenced
by the physicochemical properties of the wastes and surrounding substrates,
climatic conditions, and storage-site design and management practices that are
site-specific (Duvel et al. 1979). The accuracy of estimating quantities of
leachate seepage depends on the accuracy of permeability estimates, which
requires extensive field and laboratory testing of ash and sludge wastes and
storage-site substrates. However, given some general information about a
particular site and assuming that the storage area is unlined, some indication
of the potential for impact from seepage can be derived from the data in
Table 14. Additionally, one can obtain estimates of leachate production using
the following procedures.
Landfill Leachate Production
Order-of-magnitude estimates of leachate quantities from landfill storage
sites are obtained by assuming a given percent infiltration, with overall
hydraulic conductivity (k) of the waste or substrate being a limiting condi-
tion (Figure 33) (Duvel et al. 1979); either the overall percent infiltration
or the hydraulic conductivity of the materials can limit the leachate quantity
in each situation. A net infiltration rate of 20% of the precipitation is a
reasonable estimate for many situations. However, when site-specific measure-
ments are available, 30%, 40%, or 50% net infiltration may be more appro-
priate. Using Figure 33, if the average rainfall is 50 cm/yr (20 in./yr),
with 20% infiltration and k = 7.5 x 10-7 cm/s, the leachate seepage rate from
the storage site—which is limited by the infiltration rate in this case—
would be about 4.2 m3/ha/day (450 gal/acre/day). If k = 2.5 x 10-7 cm/s, the
leachate seepage from the storage site--which is limited by hydraulic conduc-
tivity of the materials in this case--would be about 2.1 m3/ha/day (225 gal/
acre/day). By selecting the appropriate lining materials and proper compac-
tion of the fill, hydraulic conductivity can be adjusted at a landfill site to
minimize the leachate seepage rate.
Pond Leachate Production
The quantity of seepage from a pond storage system is influenced by
permeability of the wastes and substrate, dimensions and configuration of the
pond, and boundary conditions of the entire system. Unlike landfill sites,
supernatant liquid is present as a recharge source for leachate generation.
• Figure 34 can be used to obtain an approximate estimate of seepage quantities
78
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Table 14. Potential for Adverse Effects to
Groundwater from Seepage from Unlined Ash
and Sludge Waste-Storage Sites3
Factor
Relative probability of
groundwater contamination
Nature of waste
Dry
Slurry
Acid
Alkaline
Nature of substrata*3
Granite
Shale
Sandstone
Soil
Clays
Loams
Sands, sandy loams
Rainfall zonec
< 25 cm (< 10 inches)
25-76 cm (10-30 inches)
> 76 cm (> 30 inches)
Low to moderate
High
High
Low to moderate
Extremely low
Low
Moderate
Low
High
Very high
Low
Low to high
High
.Derived from Dvorak et al. (1978)
Defined as the layer or layers of
beneath the waste, or between the
the groundwater aquifer, and may
Annual average precipitation.
natural material
waste impoundment and
include the soil.
if (1) the substrate beneath the pond is more permeable than the wastes,
(2) the depth to any impervious stratum is much greater than pond depth,
(3) the depth of supernatant is small compared to sludge depth, and (4) there
are no complex subsurface conditions. For example, if the hydraulic con-
ductivity of the sludge is 10-5 cm/s, the volume of leachate generated is
about 84 m3/ha/day (9000 gal/acre/day) (Figure 34). If substrate permeability
is less than waste permeability or if depth to an impervious layer beneath the
pond is not much greater than pond depth, the seepage quantities will be less
than predicted by using Figure 34. If the depth of pond supernatant is large,
seepage quantities will be increased; depth of pond supernatant is dependent
on net precipitation (Figure 32) and storage practices. A method for estimat-
ing seepage quantities in cases with more complex boundary conditions than
those assumed in Figure 34 has been developed by Witherspoon and Narasimhan
(1973).
79
-------
Average Annual Rainfall (Inches/year)
Figure 33. Quantity of Leachate from a Landfill. The dashed line
illustrates the infiltration-limited example and the
dotted line the conductivity-limited example on page 77.
From Ouvel et al. (1979).
80
-------
-J I I l_
I0"6 I0'5 I0"4 IQ"3
Sludge Hydraulic Conductivity, K (cm/s)
Figure 34. Effect of Sludge Hydraulic Conductivity on the Volume of
Leachate from a Pond. The dashed line illustrates the
pond leachate example on page 77. From Duvel et al. (1979).
Leachate Seepage Discharge from the Model Plant Storage Sites
The sandy loam soils and somewhat higher rainfall at the North Carolina
site means that there is a large potential for impacts from leachate seepage
from an unlined pond at this site (Table 14). The Ohio site has a slightly
higher potential for leachate dispersal than the Wyoming site because of the
higher rainfall. Dry storage at the Texas site results in the least potential
for leachate dispersal.
A permanent head of water will not be allowed to develop at the Wyoming
and Ohio waste-storage sites. Therefore, leachate discharges from the storage
81
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areas may be estimated using Figure 33. However, rainfall will pool up in the
ponds, allowing for nearly 100% infiltration of the water; in both cases, the
seepage rate is limited by hydraulic conductivity.
Seepage discharge from the Wyoming pond is limited by hydraulic conduc-
tivity of the clay liner (hydraulic conductivity = 7.5 x 10-* cm/s). There-
fore, the discharge rate is approximately 6.3 m3/ha/day (680 gal/acre/day)
through an average of 40 ha (98 acres) of 250 m3/day (9 ha-m/yr) seepage from
the storage site. Leachate from the ash wastes may alter the quantity or
quality of leachate associated with coal mining activities, but this cannot be
quantified without more detailed knowledge of the local subsurface hydrology.
Seepage discharge from the Ohio pond is limited by the clay liner (hy-
draulic conductivity = 5 x 10-7 cm/s). Therefore, the discharge rate is
approximately 4.2 nrvha/day (450 gal/acre/day) through an average of 510 ha
(1260 acres), or 80 ha-m/yr (650 acre-ft/yr) seepage from the storage site.
Seepage discharge from the Texas landfill is not limited by the hydraulic
conductivity of the ash-sludge mixture. With an average annual rainfall of
114 cm with 20% infiltration, the discharge rate is approximately 6.3 m3/ha/
day (680 gal/acre/day) through 0 to 730 ha (0 to 1800 acres) as the landfill
increases in size.
Leachate seepage at the North Carolina site is collected by the under-
drain system and recycled to the scrubber system and not discharged to the
envi ronment.
INFORMATION REQUIREMENTS AND SOURCES
The following is a list of information required to carry out an analysis of
seepage of leachate as discussed in this chapter. The most likely sources of
this information are also identified.
82
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Information required
Sources
Design and operation of the storage site
Facility operator
Climatology and meteorology
Facility operator
Natl. Weather Service
Characteristics of soils
Facility operator
Field offices of Soil
Conservation Service
Depth to water table
Facility operator
U.S. Geological Survey
Field offices of Soil
Conservation Service
MITIGATIVE MEASURES [104-106]
Steps should be taken to minimize leachate seepage to groundwater if a
problem is indicated. This is particularly important where an underlying
aquifer is either currently or potentially useful as a water supply. Contam-
ination is less likely where the difference between water table elevation and
bottom of the landfill or pond is large. Additionally, movement of leachate
seepage away from a storage site can be reduced by using liners, stabilizing
the wastes and reducing permeability, or using underdrains. However, liners
have a finite lifetime, and the seepage rate will increase as a liner deteri-
orates.
A wide variety of natural or synthetic materials may be placed on the
inside surface of an impoundment basin to reduce seepage from the basin. . The
necessity for a liner is dependent upon the properties of the ponded efflu-
ents, the quantity and chemical quality of potential leachate, the impacts of
seepage, the geology and geography of the site, the availability of process
water, and the regulations governing seepage. Liners may be grouped into five
major categories: (1) flexible synthetic liners, (2) admixed materials, (3)
soil sealants, (4) natural soil systems, and (5) stabilized wastes.
83
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Flexible Synthetic Liners
Flexible synthetic liners (e.g., polyvinyl chloride or polyethylene) are
the only "impermeable" liners. They are manufactured as long continuous
sheets that can be sealed at the edges so that each liner exactly fits the
pond. Flexible liners rely upon the earthen structure for support. They may
be vulnerable to puncture (especially during installation), aging with expo-
sure to sun or temperature extremes, reaction with ponded wastes, and stresses
from trapped gases or groundwater.
Admixed Liners
Admixed liners (such as concrete or gunites) provide some structural
support rigidity as well as reducing pond seepage, but they are not imperme-
able. The major disadvantage of rigid liners is their susceptibility to
fracture under seismic, hydrostatic, thermal, and weathering stresses.
Soil Sealants
Chemical sealants and soil additives seal the impoundment basin by fill-
ing soil interstices or by causing reactions that reduce permeability. Chemi-
cal sealants such as sodium carbonate or polyphosphates may be applied by
spraying, mixing with soil, or as additions to the waste stream inflow.
Chemical sealants are not always effective, due in part to soil nonhomogenei-
ties and in part to the sealant itself. Additionally, the chemicals them-
selves could pose toxic hazards.
Natural Soil Systems
Liners constructed of natural soil materials will generally be flexible
to some degree. They can thus withstand seismic activity and normal subgrade
settlement and are usually stable in both wet and dry conditions. In compari-
son to compacted clay and bentonite liners, liners of coarser textured soils
are relatively permeable.
Stabilized Wastes
Stabilized coal combustion and emission-abatement wastes may have value
as liners, and waste-storage capacity would be increased by incorporating the
wastes into pond embankments. However, the use of compacted wastes for liners
is not widespread.
84
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Chapter 9
Wind Erosion and Fugitive Dusting
POTENTIAL IMPACTS
[62-65]
Deposited waste materials that have low moisture content and are exposed
to strong winds are readily erodible. If proper control measures are taken,
wind erosion of ash or sludge waste-storage sites is generally expected to
result in minimal fugitive dust impacts to biota of adjacent areas.
Wind erosion moves particulate matter through three transport modes
(Figure 35):
Saltation is the skipping or leap-frogging of windblown particles over a
surface. The particles become airborne by wind gusts or by impact of other
particles, but they are too large or heavy to remain airborne for long
(Donovan et al. 1976). Surface creep is particle motion along a surface
without the particles becoming airborne. Suspension is the process whereby
particles become airborne and are transported long distances downwind; this
process is the most significant source of fugitive dust emissions (Donovan
et al. 1976). The range of particle sizes most likely to be affected by each
of the three wind erosion processes is shown in Figure 36. The majority of
fly ash particles fall into the si2e range erodible by suspension (Figure 37);
thus, the potential exists for these particles to be transported far from the
storage site. Because of the inverse relationship between fly ash particle
size and the concentration of trace elements adsorbed to the particles, the
particles most likely to become airborne also have the greatest potential for
carrying toxic trace elements.
Saltation
Surface creep
Suspension
85
-------
Saltation Surface Creep
71
6 '' -. ? ' - - " ' - '*d
* ' o'
» / ,V /I ,
Suspension
Figure 35. Transport Modes Through Which Particulate Matter is Moved
by Wind Erosion. From Donovan et al. (1976) (originally
from Witco Chemical Co. 1970).
0.05 0.1 0,
1
0,5 1.0 2.0mm diameter
Suspension
Creep
Saltation
l«l Most vulneroble
size range
Figure 36. Dominant Mode of Windblown Soil Transport as a Function
of Particle Size. Adapted from Donovan et al. (1976)
{originally from Hudson 1971).
86
-------
SIEVE ANALYSIS
CLEAR SQUARE
OPENINGS U.S. STANDARD SERIES
PARTICLE DIAMETER ft mm
Figure 37. Cumulative Grain Size Distributions for Bituminous Fly Ash.
The dashed line illustrates an example where 20% of well-
graded si 1ty sand and gravel has a particle size of 0.1 mm
or less. Adapted from GAI Consultants (1979) (originally
from Faber and DiGioia 1976).
QUANTIFICATION [63-65]
In some instances, it may be worthwhile for the investigator to attempt
to quantify wind erosion potential using the Wind Erosion Equation (Skidmore
and Woodruff 1968). The equation is used by the U.S. Soil Conservation Ser-
vice (SCS) for designing erosion control practices and for advising farmers on
87
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soil conservation programs (Woodruff et al. 1977). Thus, the investigator is
advised to consult with SCS personnel regarding appropriate applications of
the equation under considerations specific to a given storage site. The Wind
Erosion Equation is expressed as:
Soil Loss = Function of (Erodibility, Surface Roughness, Climate,
Open Field Length, and Vegetation Cover) (5)
Equation 5 is a useful tool in determining: (1) potential for wind
erosion on a site under existing conditions, and (2) conditions of surface
roughness, soil cloddiness, vegetative cover, sheltering, width, and orienta-
tion of a site necessary to reduce wind erosion to a tolerable level (Woodruff
et al. 1977). To give the reader a basic understanding of the Wind Erosion
Equation, the variables involved in the calculation of erosion loss are dis-
cussed in general below. For a detailed explanation of the equation and its
use, see Woodruff and Siddoway (1965) or Skidmore and Woodruff (1968). In
most cases, the Wind Erosion Equation will be useful as a qualitative tool for
evaluating relative potential for wind erosion and fugitive dusting.
Erodibility
The structural stability of surface materials greatly influences erosion
potential. Alternate freeze-thaw and wet-dry cycles as well as raindrop
impact tend to cause disintegration of surface aggregates, resulting in
increased erosion potential. On the other hand, rainfall or wetting may
consolidate certain fine-grained materials, such as ash and subsequent drying
results in formation of a crust that is relatively resistant to wind erosion.
Aside from structural relationships, the density and particle size (Figure 36)
of surface materials also influence erosion and dusting. For a given frac-
tion, the lighter particles are more readily displaced. Materials comprised
of a high proportion of fine particles are strongly cohesive and highly resis-
tant to wind erosion unless the surface layers are disturbed.
Surface Roughness
Small ridges and depressions, clods, and surface aggregates collectively
contribute to the roughness of an erodible surface. These surface irregulari-
ties alter wind speed by absorbing and deflecting some of the wind energy.
Microrelief of 5 to 12 cm (2 to 5 inches) is considered the most effective in
limiting wind erosion losses (Woodruff et al. 1977). Greater microrelief
causes increased wind turbulence and therefore increased erosion.
Vegetative Cover
The presence of living vegetation and/or vegetative residues reduces the
erosion potential of a given area. When determining the wind erosion poten-
tial of a waste-storage site before final revegetation, vegetative cover will
likely be zero.
88
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Open-Field Length
For a single erosion event, the erosion loss from an unprotected open
area is strongly dependent on the length of eroding surface in parallel with
the direction of the erosive wind. If the eroding area is of sufficient
length, the sediment load increases to the maximum that the wind can sustain,
and the rate of erosion remains constant regardless of additional length of
eroding surface.
CIimate
Characteristics of the climate that affect wind erosion include wind,
precipitation, temperature, and humidity. Wind is the energy source for the
erosion process, and the effects of the process vary with the velocity, turbu-
lence, direction, and duration of wind flow. Erosion is initiated when wind
action is sufficient to dislodge and transport surface particles. Given
initial particle transport, the rate of erosion increases with incremental
increases in wind speed; i.e., under otherwise comparable conditions, the rate
or erosion for a 48-km/h (30-mph) wind is more than three times that for a
32-km/h (20-mph) wind (Woodruff et al. 1977).
IMPACT ANALYSIS
Evaluating the Potential for Wind Erosion
and Fugitive Dusting
[62-65]
Analyses and integration of information obtained by literature review and
field reconnaissance will usually provide an adequate basis for evaluating
wind-erosion potential at a proposed waste-storage site. In many instances,
accurate prediction of the potential intensity of wind erosion from a given
waste-storage site is difficult; however, because most wind erosion/dust
suppression methods are highly effective, the impacts associated with wind
erosion and fugitive dusting will often be minimal when these methods are
employed.
For a given ash and sludge storage method, the potential for wind erosion
and fugitive dust production will vary as a function of climatic factors
including precipitation, evaporation, and wind speed. Wind erosion is more of
a problem in areas of low, variable precipitation where drought is frequent
and in areas where temperature, evaporation, and wind speeds are high
(Woodruff et al. 1977). Coal combustion waste-storage facilities in these
areas will lose moisture quickly and be subject to high wind energy.
Given these considerations and information on regional mean annual pre-
cipitation, evaporation, and wind speed [see U.S. Department of the Interior
(1970)], it is possible to indicate the potential for wind erosion in various
regions of the country. Brady (1974) indicates that there are two areas
within the western Midwest and lower near West regions that have the highest
potential for wind erosion in the United States: (1) the central portions of
North Dakota, South Dakota, and Nebraska; and (2) the western portions of
Kansas, Oklahoma, and Texas; and southeastern Colorado and eastern New Mexico.
89
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Local topographic features also modify wind erosion by reducing exposure
to wind erosion. Ash and sludge wastes stored in flat, exposed areas will be
more subject to wind erosion than those stored in hilly, forested areas. In
this regard, ash and sludge wastes in the Northeast and Southeast will be
least subject to wind erosion because of generally hilly terrain and large
forested areas. The Prairie and Great Plains regions have large flat areas
with no forests, and ash and sludge wastes stored in these areas will be
subject to high wind erosion. Wind energy effects on ash and sludge wastes in
the eastern Midwest will be more moderate because of an interspersion of hilly
and flat areas with prairie and forested areas.
Impact of Wind Erosion and Fugitive Dust
at the Model Storage Sites
In the model sites where combustion wastes will be stored in diked ponds
(Western, Ohio, and North Carolina plants), fugitive dusting from the stored
wastes will be low. In ponds containing wet materials, fugitive dust emis-
sions may occur if the basin surfaces dry. Storage pond dikes will be
designed such that wind erosion is minimized to protect dike integrity.
Measures will have to be taken to control fugitive dust during the interim
between basin surface drying and the final reclamation of the storage pond.
The choice of mitigative measures will be limited because the surface of the
ponded wastes will probably not be able to withstand the weight of tillage
equipment or heavy-duty vehicles.
Trucking ash to the surface mine adjacent to the Wyoming plant poses the
potential for fugitive dust problems along haul roads. The site is located in
an area of high winds, low rainfall and negative net precipitation. Fly ash
particles are susceptible to wind entrainment (Figures 36 and 37), and appli-
cation of water or chemical stabilizers will be necessary to reduce fugitive
dusting during transport.
Fugitive dusting is also likely to occur from the ash landfill storage
site of the Texas plant. These emissions will occur as the result of heavy
equipment operations during waste deposition and compaction, as well as from
exposed surfaces of deposited ash. Water application to haul roads and in
conjunction with surface compaction activities will reduce fugitive dust
emissions associated with the operation of the landfill. Emissions from
exposed surfaces can be reduced by the timely application of the clay cap and
topsoil layer. The establishment of vegetation on the topsoil will reduce
dust emissions from this material.
90
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INFORMATION REQUIREMENTS AND SOURCES
The following is a list of information required to carry out an analysis of
fugitive dusting as discussed in this chapter. The most likely sources of
this information are also identified.
Information required
Sources
Methods used to suppress dust and prevent
wind erosion
Site visit
Facility operator
Field offices of Soil
Conservation Service
Data required to apply Wind Erosion Equation;
determination if Wind Erosion Equation
is applicable to a given site
Field offices of Soil
Conservation Service
Precipitation, evaporation potential, and
wind velocity and direction
Natl. Weather Service
Facility operator
Local topography
Site visit
U.S. Geological Survey
Habitat of areas adjacent to waste-storage site
Site visit
Facility operator
Field offices of Soil
Conservation Service
MITIGATIVE MEASURES [107-111]
Many of the mitigative measures used in controlling water erosion are
also effective in reducing wind erosion and fugitive dusting. Although these
methods can be categorized as involving physical, chemical, and vegetative
processes, the basic purpose of all control methods is to modify one or more
91
-------
of the parameters of the Wind Erosion Equation (Equation 5). The usefulness
of a given procedure varies according to site-specific conditions and the
method of waste deposition. In most cases, a combination of procedures will
be required to adequately control wind erosion.
Physical Methods
Procedures included in this category involve efforts to reduce the local
wind velocity across the surface of the wastes or physically stabilize the
erodible surfaces of deposited waste material. Wind barriers oriented at
right angles to the prevailing wind direction can effectively protect a lee-
ward area for a distance of approximately 15 times the height of the barrier
(Woodruff et al. 1977). Typical wind barriers are solid wood fences or snow
fences, although it may be feasible to establish tree and/or shrub shelter-
belts on areas directly adjacent to waste-storage sites.
Tillage equipment can be used to roughen or ridge the surface of depos-
ited wastes to reduce wind velocity and trap windborne particles. However,
the operation of tillage equipment on waste surfaces may not always be prac-
tical, especially in the case of ponded scrubber sludge. The most widespread
technique for stabilizing the surfaces of deposited waste materials is through
water application in conjunction with surface compaction. This technique is
particularly effective for fine-grained materials such as fly ash. Other
physical methods of surface stabilization include the crimping of organic or
inorganic mulches into the waste surface and the application of thin layers of
coarse gravel, country rock, or crushed stone. The latter materials have
proven to be useful in arid areas where wind velocities are consistently high.
Chemical Methods
The application of chemicals to waste surfaces causing the formation of a
surface crust can significantly reduce the wind erodibility of fine-grained
particles. A list of chemicals shown to be effective in the formation of
surface crusts (e.g., potassium and sodium silicates) can be found in Dean
et al. (1974).
Vegetative Methods
The vegetation of a site absorbs some wind energy, thereby reducing local
wind velocity; it also intercepts or entraps windborne particles, reducing the
amount of material removed from the eroding surface. Additionally, root
systems help to bind soil or waste particles together. Although the opportu-
nity to establish vegetation directly upon waste surfaces prior to the final
reclamation of the disposal site will be dependent on site-specific condi-
tions, it seems unlikely that vegetative methods will be used to temporarily
stabilize coal-combustion waste surfaces.
92
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Chapter 10
Consequences to Biota
POTENTIAL IMPACT
[65-71,
75-81]
Runoff, seepage, and dusting are means by which potentially toxic con-
stituents of ash and FGD sludge are mobilized and dispersed from storage sites
into terrestrial and aquatic environments. Organisms can also serve as agents
for dispersal by absorbing these constituents from their physical environment
and diluting, concentrating, transforming, and immobilizing them--thus affect-
ing their ultimate toxicity (Van Hook 1978).
Biological pathways of dispersal in terrestrial ecosystems include:
• Microbial interactions in soil
¦ Plant uptake from the soil-soil water continuum
• Translocation in plant tissues
• Food-chain transmissions to primary and secondary consumers
Biological pathways of dispersal in aquatic ecosystems include:
• Microbial-sediment interactions
• Absorption and adsorption from water by phytoplankton
• Food-chain transmission to consumers
• Direct uptake from water by consumers
Direct uptake from air through inhalation by animals can occur in ter-
restrial systems, but probably does not represent a major food web pathway for
coal ash and FGD sludge constituents.
93
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Concentration and toxicity of trace elements in plants are element- and
species-specific, as well as site-specific. A number of environmental and
physiological factors can affect uptake, accumulation, and toxicity of trace
elements. Moreover, trace elements have a variety of effects on plants inclu-
ding changes in physiology, productivity, reproductive success, community
composition, and species abundance.
Differential accumulation of toxic elements in terrestrial and aquatic
plant tissues may determine which elements are ingested by fish and wildlife
foraging on different plant tissues. Most terrestrial plant species tend not
to readily translocate As, Be, Cr, Pb, Ni, and V from the root; whereas B, Cd,
Cu, Se, and Zn, among others, are more readily translocated to the shoot.
Based on the literature and their own experiments, Wallace and Romney (1977)
have tentatively placed a number of trace elements into three groupings re-
garding element distribution between roots and shoots:
1. Reasonably uniformly distributed: Zn, Mn, Ni, Li, B.
2. Usually more in roots than in shoots, but often moderate with some-
times large quantities in shoots: Fe, Cu, A1, Cd, Co, Mo.
3. Mostly in roots with very little in shoots: Pb, Sn, Ti, Ag, Cr, V,
Zr, Ga.
These generalizations are not always true for all species under all condi-
tions, particularly when very high levels of an element are present in the
soi 1.
One pathway by which potentially toxic substances could come in contact
with wildlife is ingestion of impoundment liquors. Particularly in arid
areas, waste ponds could be attractive watering sites for local or migrating
wildlife, resulting in potential toxic impacts to the wildlife or disruption
of their migratory patterns.
Little is known about the potential for toxic effects of ash and sludge
waste constituents to animals. The effects that have been demonstrated re-
quired direct ingestion of ash in acute dosages. The best indicator of poten-
tial impacts to herbivores is probably obtained from looking at plant tissue
concentrations of trace elements known to be toxic to animals. Less is known
about the toxicity and mutagenicity of organic constituents of coal combustion
wastes.
Biological effects of exposure to a single trace contaminant can be
modified by addition of one or more different trace contaminants. Interaction
effects with biota can be:
• Additive - Same as the sum of exposure to the
individual components
• Antagonistic - Less than the effects of each
component taken additively
94
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Synergistic - Greater than additive effects
Emissions from combustion waste-storage sites are likely to contain complex
mixtures of potentially toxic materials, making it imperative that the complex
mixtures, themselves, and not just the individual constituents be studied for
potential toxicity on a site-specific basis.
There are a number of studies that present data on toxicity of various
contaminants for fish, wildlife, and plants. Recent studies include Cleland
and Kingsbury (1977), Gough et al. (1979), and Johnson and Finley (1980).
QUANTIFICATION AND IMPACT ANALYSIS [71-72]
The actual magnitude of impacts to fish and wildlife from ash and sludge
wastes is extremely site- and species-specific. Only after extensive studies
of a given situation can one make site-specific predictions of impacts to
biota contacting constituents of these wastes. In most cases, such studies
will not have been carried out on projects which the fish and wildlife biolo-
gist reviews. Additionally, it will be difficult to predict accident scenar-
ios and associated impacts to fish and wildlife.
One method of estimating impacts to fish and wildlife (Lewis et al. 1978)
is to assume that at equilibrium the concentration of a given trace element in
the soil as a result of seepage will be the same as the concentration in the
leachate and will be in a form available for biotic uptake (losses through
leaching and soil binding being ignored). Plant concentrations are then
calculated using pi ant:soi1 concentration ratios (e.g., Table 15), which are
multiplied by 10 to provide a safety margin. These values are compared with
normal concentration ranges and suggested maximum tolerable concentrations in
plant leaves and with trace-element concentrations known to be toxic to ani-
mals (cf. Gough et al. 1979).
Lewis et al. (1978) recognized a number of limitations in their method.
In addition to the imprecision inherent in predicting concentrations in vege-
tation (particularly cumulative concentrations in perennials), there are
uncertainties in estimating toxic levels in different animal species due to
differences in excretion rates, quantity of the vegetation species consumed,
quantity of other food in the diet, physiological response to a given con-
centration in the diet, and effects of long-term consumption of supposedly
nontoxic concentrations.
Due to the lack of species- and site-specific data, a set of impact
criteria have been adopted in this manual for quantification purposes. Gener-
alized criteria for determining the potential harm to human health and the
environment have been developed by Cleland and Kingsbury (1977) under the
sponsorship of the USEPA. These criteria, termed "estimated permissible
ambient concentrations" (EPC), represent indicator thresholds above which
deleterious effects may occur to biota (including wildlife resources) during
chronic long-term exposure. If the estimated amount of a given constituent of
coal combustion waste exceeds an EPC, it does not necessarily mean an adverse
impact will occur but indicates there is a potential for deleterious effects
that requires further scrutiny.
95
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Table 15. Generalized Biological Concentration Factors for Elements in Aquatic and
Terrestrial Ecosystems3
Concentration factor ([biota]/[growth medium])**
Element
Terrestrial
Freshwater
Marine
Plant
Animal
Macrophyte
Invertebrate
Fish
Plant
Invertebrate
Fish
A1 umi num
0.007
0.001
_c
-
-
6,000
-
-
Antimony
0.03
0.003
-
10
1
-
5
40
Arsenic
~0.03
0.03
1,000
300
300
10,000
300
300
Barium
0.03
0.002
-
-
-
1,000
-
-
Beryllium
0.02
0.0003
-
10
2
2,000
200
200
Boron
5
0.02
-
-
-
30
-
-
Cadmi um
10
8
4,000
2,000
200
4,000
200,000
3,000
Chromium
0.002
0.0008
2,000
-
-
20,000
-
-
Cobalt
M). 06
0.004
4,000
-
-
2,000
-
-
Copper
~0. 7
0.1
200
1,000
200
4,000
2,000
1,000
Fluorine
M).2
3
-
-
-
3
-
-
Lead
M). 3
0.2
500
100
300
300,000
1,000
200
Manganese
¦vO.7
0.0002
200
-
-
30,000
-
-
Mercury
0.5
2
200,000
100,000
1,000
1,000
30,000
2,000
Molybdenum
~0.4
0.1
1,000
-
-
40
-
-
Nickel
-n-0.08
0.02
3,000
100
100
600
200
100
Selenium
1
10
-
200
200
10,000
1,000
4,000
Vanadium
0.016
0.002
-
-
-
1,000
-
-
Zinc
%2
3
5,000
10,000
1,000
20,000
100,000
2,000
.Data from Bowen (1966), Braunstein (1978), and Hutchinson (1975).
Growth medium: soil for terrestrial biota, water for aquatic biota.
A hyphen indicates data not available.
-------
Permissible concentrations for the protection of health (EPCh) were
derived by CI eland and Kingsbury (1977) from laboratory animal toxicological
studies using acute exposures. These values can be used as indicators of the
potential for adverse direct impacts to wildlife. The EPCh for soils repre-
sent threshold limits for wildlife via their food, whereas the EPCh for water
represent threshold limits for ingestion of water. Permissible concentrations
in soils for the protection of the environment (EPC^) were derived from
studies of plant toxicology. These values may be used as indicators of the
potential for adverse indirect impacts to wildlife, i.e., impacts to wildlife
habitat.
EPC values in Table 16 are less than threshold values for acute toxicity.
Dilution factors were applied to toxicity threshold values in order to reflect
the lower concentrations required to elicit responses during chronic exposure,
which is the type of exposure most likely for wildlife in waste-handling
areas.
The elemental concentrations presented in Table 16 are for constituents
in solution; thus, in general, the values represent amounts potentially avail-
able for biological uptake. For soils, this amount can be considerably less
than the total amount of the element in a unit of soil.
The approach presented here does have limitations. The complex inter-
actions of trace elements and other factors in the environment cannot be
easily quantified and incorporated into the evaluation of impacts to biota.
The criteria in Table 16 are only for trace elements, and we have not con-
sidered potential impacts from other constituents of the coal combustion
wastes, e.g., organic compounds and sulfites. Moreover, the criteria are
generalized from data on different organisms and do not precisely apply to
site-specific situations. Therefore, predictions of impacts from coal and FGD
sludge contain a degree of uncertainty. As more research data are accumu-
lated, more sophisticated approaches can be devised.
Terrestrial Wildlife
Where data on ambient concentrations of constituents dispersed from
wastes are unavailable, a worst-case scenario may be developed for analysis.
As illustrated in Table 17, maximum soil concentrations of waste constituents
can be estimated from estimated concentrations in the leachate from a coal
combustion waste-storage site. Soil bulk density was assumed to be 1.5 g/cm3
and soil water content 33%. If leachate replaces all soil water, concentra-
tions of the elements in the soils are given by:
Ci x 0.33
C = (6)
s 1.5 g/cm3 x 1000 cm3/L
where C is the soil concentration (pg/g) and Cj is the leachate concentration
(|jg/L). Maximum water concentrations of the elements can be taken as the
97
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Table 16. Estimated Permissible Ambient Concentrations (EPC)
of Ash and Sludge Waste Constituents3
EPCh EPCE
Water
Soil or sediment
Water
Soil or sediment
Constituent
fpg/L)
(msi/s)
(HflA)
(pg/g)
Aluminum
73
0.15
200
0.4
Antimony
7
0.014
40
0.08
Arsenic
50
0.1
10
0.02
Barium
l,OOOb
2b
-
-
Berylli um
-
-
llb
0.022b
Boron
43
0.09
5,000
10
Cadmium
10
0.02
0.4
0.0004
Chromium
50
0.1
50
0.1
Cobalt
0.7
0.001
50
0.1
Copper
1,000
2
10
0.02
Lead
50
0.1
10
0.02
Manganese
50
0.1
20
0.04
Mercury
2
0.004
0.05b
0.0001b
Molybdenum
70
0.14
1,400
0.02
Nickel
1.4
0.003
2
0.C04
Selenium
10
0.02
5
0.01
Strontium
27
0.05
-
-
Vanadium
7
0.014
75
0.15
Zinc
5,000
10
20
0.04
Data from Cleland and Kingsbury (1977), except as indicated. EPCh are
permissible concentrations for health effects; EPC^ are permissible
concentrations for environmental effects. EPC in soil or sediment repre-
sent amounts available for biological uptake, i.e., that dissolved in soil
¦ solution.
Data from U.S. Environmental Protection Agency (1976).
concentrations in the leachate. In this example (Table 17), the elements most
likely to cause problems for wildlife are boron, nickel, and vanadium--values
for which all markedly exceed EPC.
98
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Table 17. Factors by Which Maximum Ambient Concentrations Exceed Estimated
Permissible Ambient Concentrations (EPC) for a Waste-Storage Site3
Concentration
(pg/L) in
1eachateb
Factors
health
based on
effects
Factors based on
environmental effects
Element
Water Soil
or sediment
Soil or sediment
Antimony
16
2
<1
<1
Arsenic
19
<1
<1
<1
Bari urn
640
1
<1
-
Beryllium
2
-
-
<1
Boron
1840
43
4
<1
Cadmi um
1
<1
<1
1
Chromium
171
3
<1
<1
Copper
19
<1
<1
<1
Lead
5.4
<1
<1
<1
Manganese
2
<1
<1
<1
Mercury
0.6
3
<1
1
Molybdenum
158
2
<1
2
Nickel
50
36
4
<1
Seleni um
92
9
1
2
Vanadium
100
14
2
<1
Zinc
20
<1
<1
<1
The factors were calculated by dividing the values for concentration (pg/L)
.in leachate by the EPC values from Table 16.
Derived from Holland et al. (1975).
The many complex interactions that may occur among constituents of ash
and sludge wastes have not been taken into account for the values listed in
Table 16. For general assessment purposes, it can be assumed that the inter-
actions are additive and that the potential for adverse effects exists if any
waste constituent present in the environment occurs at a concentration higher
than the EPC value for that constituent as given in Table 16.
Sophisticated levels of assessment cannot be accomplished without more
detailed site-specific information, including more complex models of (1) the
interactions of the abiotic and biotic components of the affected ecosystem
and (2) the dispersal and interactions of waste constituents. In most in-
stances, however, these detailed data and analyses will not be available.
99
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Aquatic Biota
[81-82]
Generalized criteria for determining the potential for harm to aquatic
biota have also been developed by Cleland and Kingsbury (1977). These cri-
teria are the EPCf for water listed in Table 16 and are equivalent to the
USEPA's "quality criteria for water." Expected concentrations of trace ele-
ments in the waste liquors can generally be obtained from the operator of the
proposed facility. With this information, one can calculate a dilution factor
(Df) or factor by which leachate concentration exceeds EPC:
Cg is the concentration of a constituent in the waste leachate or discharge
effluent and EPC is the estimated permissible concentration of that constitu-
ent (from Table 16). The dilution factors can be used as indicators of which
waste constituents discharged or leached into surface waters could pose poten-
tial hazards to aquatic biota. For example, for the waste-handling facility
in Table 18, the elements mercury, selenium, and nickel will require the
greatest amount of dilution before they can be brought to levels that will
ensure protection of aquatic life. When the concentrations of elements in
waste discharge are known, the same approach can be used to indicate potential
problem areas for other situations.
If effluents, including leachate seepage, from ash and sludge waste-
storage sites are discharged into flowing surface waters, the following rela-
tionship can be used to conservatively predict receiving-stream flows that are
required to achieve acceptable EPCg values for potentially toxic discharge
constituents, vn'th no losses after complete mixing:
Dr is the receiving-stream flow; De is the effluent flow; Ce is the effluent
concentration of a given constituent; Cr is the ambient receiving-stream
concentration of a given constituent before effluent addition (generally
considered to be zero for nonpolluted streams); and EPC is the permissible
concentration of a given constituent in the receiving water after complete
mixing (Table 16).
The complex interactions that occur between discharge constituents and
receiving-stream biota can be conservatively modeled by an additive relation-
ship. Information on receiving-stream and discharge flows and chemistry may
be available from the operators of the proposed facility. If receiving-stream
flows are above the calculated Dr for a given constituent or combination of
constituents, one can generally conclude that aquatic biota in the receiving
(7)
Dfl(C -EPC)
Cr = ——
r EPC-Cr
(8)
100
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stream will be unaffected by the operation. Where the measured flow of the
receiving stream is less than Dy, the likelihood for impact is indicated" The
actual degree of environmental impact caused in aquatic ecosystems by ash and
sludge waste storage will be dependent on the quantity and quality of storage-
site discharges, receiving-stream flows, and other site-specific variables.
Table 18. Dilution Factors Required to Achieve
Estimated Permissible Ambient Concentrations
(EPC) for Water of Coal Combustion
Waste Constituents from a
Waste-Handling Facility3
Element
Concentration (pg/L) .
in discharge or seepage
Dilution
factors
Antimony
16
<1
Arsenic
19
2
Barium
640
-
Beryllium
2
<1
Boron
1840
<1
Cadmi um
1
2
Chromium
171
3
Copper
19
2
Lead
5.4
1
Manganese
2
<1
Mercury
0.6
12
Molybdenum
158
<1
Nickel
50
25
Selenium
92
18
Vanadium
100
1
Zinc
20
1
The factors were calculated by dividing the values
for concentration (pg/L) in discharge or seepage by
.the EPC values from Table 16.
Derived from Holland et al. (1975).
101
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Impact of Effluent Discharges, Runoff Dispersal, Leachate Seepage,
and Wind Dispersal at the Model Plants
Effluent discharges. Surface discharges from waste-handling procedures
at the Wyoming, Ohio, Texas, and North Carolina model plants are assumed to
have the constituent concentrations and discharge volumes outlined in
Tables 19-22, respectively.
Receiving-stream flows at the Wyoming, Ohio, and Texas sites are, respec-
tively: 8.0 m3/s (280 cfs); 3.0 x 103 m3/s (1.0 x 105 cfs); and 3.0 m3/s
(100 cfs). These rates should be sufficient to dilute potentially toxic
constituents to acceptable EPC. There should be little biological concentra-
tion and magnification of potentially toxic constituents to toxic levels at
the storage site areas based on concentration factors presented in Table 15.
There is no effluent discharge at the Wyoming facility; thus, only in the
immediate vicinity of the Ohio and Texas discharge sites is there potential
for gradual accumulation of potentially toxic constituents.
Surface discharges from the North Carolina storage pond [1.9 x io-1 m3/s
(7 cfs)] enter a small stream (average annual flow = 3 x io-1 m3/s or 10 cfs)
which flows into a large estuary. The stream does not provide sufficient flow
to dilute some constituent concentrations to EPC in the water (Tables 16
and 22). However, the estuary provides sufficient volume and flow to dilute
total constituent concentrations to acceptable EPC in water, with the possible
exception of nickel. There will be a potential for biological concentration
and magnification of potentially toxic constituents to toxic levels in the
stream (500 m in length) before it enters the estuary based on the biocon-
centration factors presented in Table 15. Although the discharge will be
rapidly diluted in the estuary, biological concentration occurring in the
stream could impact estuarine organisms. There could also be high background
concentrations of potentially toxic constituents (particularly nickel) and,
with addition of the discharge, critical levels required for protection of
fish and wildlife could be exceeded. The discharge will be a long-term addi-
tion to the stream and estuarine system, and there could be biomagnification
of potentially toxic trace elements in food webs leading to the bald eagle,
American alligator, and important fishery species.
Runoff dispersal. If proper erosion-control techniques are used, runoff
dispersal from the model storage sites should result in little, if any, move-
ment of potentially toxic combustion wastes and should have little impact on
fish and wildlife.
Wind dispersal. If proper erosion-control techniques are used, wind
dispersal from the model storage sites should result in minor movement of
potentially toxic combustion wastes and should have little impact on fish and
wild!i fe.
102
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Table 19. Factors by Which Elemental Concentrations
in Leachate Exceed Estimated Permissible Ambient
Concentrations at the Western
Model Power Planta
Element
Concentration
in leachate^
(ng/L)
Water
Soil
or
Sediment
Antimony
14
<1
<1
Arsenic
2
<1
<1
Beryllium
2
<1
<1
Boron
2600
1
<1
Cadmium
0.5
1
<1
Chromium
1
<1
<1
Copper
31
3
<1
Lead
5.6
1
<1
Manganese
2
<1
<1
Mercury
0.5
10
1
Molybdenum
63
<1
1
Nickel
50
25
3
Selenium
45
9
1
Vanadium
100
1
<1
Zinc
5
<1
<1
?No surface discharge.
From Holland et al. (1975).
103
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Table 20. Factors by Which Elemental Concentrations
in Leachate Exceed Estimated Permissible Ambient
Concentrations at the Ohio River Valley
Model Power Plant3
Element
Concentration
in leachateb
(|jg/L)
Water
Soil
or
Sediment
Antimony
22
1
<1
Arsenic
72
7
<1
Beryl 1ium
1
<1
<1
Boron
1100
<1
<1
Cadmium
1
2
1
Chromium
1000
20
2
Copper
13
1
<1
Lead
4.3
<1
<1
Manganese
2
<2
<1
Mercury
0.3
6
1
Molybdenum
690
<1
8
Nickel
50
<1
3
Selenium
470
94
10
Vanadium
200
3
<1
Zinc
5
<1
<1
Surface discharge = 750 ha-m/yr (6100 acre-ft/yr) or
h2.4 x 10-1 m3/s (8.4 cfs).
From Holland et al. (1975).
104
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Table 21. Factors by Which Elemental Concentrations
in Leachate Exceed Estimated Permissible
Ambient Concentrations at the
Texas Model Power Plant3
Element
Concentration
in leachateb
(Mfl/L)
Water
Soil
or
Sediment
Antimony
18
<1
<1
Arsenic
84
8
1
Beryllium
0.6
<1
<1
Boron
16,900
3
<1
Cadmium
2.5
6
1
Chromium
210
4
<1
Copper
31
3
<1
Lead
2.7
<1
<1
Manganese
2
<1
<1
Mercury
0.5
10
1
Molybdenum
52
<1
1
Nickel
15
8
1
Selenium
0.5
10
<1
Vanadium
100
1
<1
Zinc
25
1
<1
aSurface discharge = 95 ha-m/yr (750 acre-ft/yr) or
h3 x io-2 m3/s (1 cfs).
From Holland et al. (1975).
105
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Table 22. Factors by Which Elemental Concentrations
in Leachate Exceed Estimated Permissible Ambient
Concentrations at the Southeastern Coastal
Model Power Plant9
Element
Concentration
in leachate^
(ijg/O
Water
Soi 1
or
Sediment
Antimony
8.7
<1
<1
Arsenic
6
1
<1
Beryllium
0.3
<1
<1
Boron
48
<1
<1
Cadmi um
1.1
3
1
Chromium
14
<1
<1
Copper
15
2
<1
Lead
6.3
1
<1
Manganese
2
<1
<1
Mercury
0.3
6
1
Molybdenum
10
<1
<1
Nickel
46
23
2
Selenium
0.5
<1
<1
Vanadi um
100
1
<1
Zinc
17.5
1
<1
Surface discharge = 620 ha-m/yr (5050 acre-ft/yr) or
.1.9 ^ 10-1 m3/s (7 cfs).
From Holland et al. (1975).
106
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Leachate seepage. Concentrations of leachate seepage constituents from
waste-handling procedures at the Wyoming, Ohio, Texas, and North Carolina
plants are presented in Tables 19-22. Maximum hydraulic conductivities
through the wastes and underlying substrates at three sites are as follows:
Maximum hydraulic conductivities (cm/s)
Model site Wastes Substrates
Wyomi ng
7.5 x
10-7
1 x
10-4
Ohio
5 x
10-7
1 x
10-4
Texas
1 x
10-6
2 x
1
O
Movement through the substrate is substantially faster. Leachate seepage at
the North Carolina site is collected by the underdrain system and recycled to
the scrubber system.
Assuming that the substrate is 33% water by volume, leachate movement
away from the Wyoming, Ohio, Texas, and North Carolina sites should be suffi-
cient to dilute the total constituent concentrations to EPC in the soil
(Tables 16 and 19-22). There should be little biological concentration and
magnification of potentially toxic constituents to toxic levels at the
storage-site areas based on concentration factors presented in Table 15.
Therefore, little short-term impact to biota is expected due to leachate
seepage. However, in the immediate vicinity of the Wyoming, Ohio, and Texas
sites, there is potential for accumulation of constituents from leachate
seepage in soih As a result of physical and chemical processes, including
soil reaction pH, concentrations of several constituents could exceed EPC
values, including nickel at the Wyoming site and molybdenum and selenium at
the Ohio site. Additionally, if there are high background concentrations of
potentially toxic constituents at the sites, critical levels required for
protection of fish and wildlife resources could be exceeded with the addition
of leachate seepage constituents.
107
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INFORMATION REQUIREMENTS AND SOURCES
The following is a list of information required to carry out an analysis of
consequences to biota as discussed in this chapter. The most likely sources
of this information are also identified.
Information required
Sources
Runoff and effluent discharges from the
storage site
See RUNOFF
Seepage from the storage site
See SEEPAGE
Dusting from the storage site
See WIND EROSION AND
FUGITIVE DUSTING
Habitat data including soils, water, and
biological assemblages
Site visit
Facility operator
Field offices of Soil
Conservation Service
U.S. Fish and Wildlife
Service
Toxicity data
Facility operator
Reclamation plans
Facility operator
MITIGATIVE MEASURES
Impacts to biota can be mitigated by minimizing runoff, seepage, and
dusting dispersal of potentially toxic ash and FGD sludge waste constituents
from storage sites (see Mitigative Measures for RUNOFF* SEEPAGE and WIND
EROSION AND FUGITIVE DUSTING). Additionally, wildlife can be discouraged from
using impoundments by means of fences, netting* scarecrows, or noisemakers.
Plans can be developed to protect fish and wildlife resources in the event of
catastrophic release of wastes.
108
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Chapter 11
Reclamation of Waste-Storage Sites
INTRODUCTION
[115-129]
Currently, there is no federal regulatory program addressing requirements
for acceptable reclamation of coal combustion waste-storage sites. However,
regulations recently implemented or newly promulgated through federal and
state laws, outlining standards for waste storage and the protection of water
resources, have provided the impetus for careful planning of waste-storage-
site retirement (GAI Consultants 1979). This will most likely result in the
development of a reclamation program for a proposed waste-storage facility.
The reclamation plan should describe, in some detail, practices useful for
erosion and sediment control, vegetation establishment, postreclamation moni-
toring, and future land uses.
In the section that follows, the components of a comprehensive reclama-
tion program will be discussed to give the reader an introduction to the types
of information needed to develop such a plan. Although it is difficult to
accurately predict whether a proposed reclamation plan will result in the
successful rehabilitation of a given storage site, it is possible to judge the
adequacy of the planning effort for closure of a facility.
PREDISTURBANCE SITE DESCRIPTION
During the process of selecting a waste-storage site, a great deal of
baseline data concerning the existing environmental conditions of candidate
sites are gathered. CIimatological data are helpful in selecting appropriate
plant species for use in revegetation, in determining the schedule of plant-
ing, and in designing erosion and sediment control structures. A vegetation
survey of the proposed site and adjacent habitats identifies the plant species
and plant community types adapted to local climatic and edaphic conditions.
Soil surveys of the proposed storage site aid in determining the potential
available volumes of topsoil, friable subsoil, and low permeability subsoil.
The quality, thickness, spatial distribution, and quantity of the soil re-
109
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source at a given site dictates the type of artificial soil profile construc-
ted over the deposited waste materials, which in turn will determine the
success of revegetation and erosion control practices. Analyses of the tex-
ture, fertility, and pH of the soil aid in determining application rates of
fertilizer, lime, and other soil amendments.
WASTE-STORAGE SITE DESIGN [129]
Certain design characteristics (e.g., length and gradient of slopes) will
influence the types of reclamation practices employed and the subsequent
revegetation of the storage site. Therefore, one should become familiar with
the proposed engineering design of a given storage facility before evaluating
the reclamation program for that facility.
Storage-site design characteristics that influence reclamation will, in
turn, be greatly influenced by regulations promulgated under the Resource Con-
servation and Recovery Act of 1976 (RCRA). Although the regulatory program
for RCRA is currently incomplete, proposed guidelines for regulations could
have a significant impact on erosion control practices, revegetation, and clo-
sure of ash and FGD sludge storage sites (GAI Consultants 1979). These guide-
lines include:
• Construction of runoff diversion structures.
• Inclusion of terraces at 6-m (20-ft) vertical intervals.
• Seeding the final soil cover.
• Making landfill grades no greater than 33%.
• Routing offsite runoff and uncontaminated onsite runoff to
a sedimentation basin prior to discharge.
• Preparing a final landfill cover with 15 cm (6 in.) of
clay followed by 45 cm (18 in.) of soil capable of
supporting vegetation, the upper 15 cm (16 in.) of which
must be topsoil or soil-covering material with plant
production capacity greater than or equal to the original
soil.
• Maintaining the landfill in an aesthetic manner.
WASTE-STORAGE SITE REVEGETATION [127-129]
When preparing a waste-storage disposal site for closure, one of the
principal concerns is development of measures to prevent the dispersal of
deposited wastes into the surrounding environment. Good vegetation cover and
proper design of a water-disposal system are needed in controlling erosion and
stabilizing waste surfaces (Donovan et al. 1976). It is difficult to estab-
lish vegetation directly upon coal ash or FGD sludge because plant growth is
110
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inhibited by a variety of toxic constituents of these materials (e.g., high
boron and soluble salt content) and the lack of essential plant nutrients
(nitrogen and phosphorus). Although vegetation has been established directly
upon fly ash following the addition of organic materials or fertilizer (Rippon
and Wood 1975; Townsend and Gill ham 1975) or following the weathering and
leaching of the deposited ash (Townsend and Gillham 1975), little effort has
been made to directly revegetate FGD sludge. In either case, the development
of self-perpetuating plant communities as a result of direct seeding of waste
surfaces has not been demonstrated. Currently, one can conclude that the
direct revegetation of waste surfaces is not a viable reclamation practice.
Since coal combustion wastes appear to be, at best, marginal plant growth
materials, successful reclamation of storage sites will require the placement
of a soil mantle over the waste materials to help ensure the establishment of
vegetation and reduce erosion. The depth of the soil mantle will play an
important role in determining revegetation success. A primary factor affect-
ing soil mantle thickness is the moisture regime of the storage site. In arid
regions of the country, a thick soil mantle may be required to sustain plant
growth, whereas a thinner mantle may be acceptable in more mesic regions.
A review of several experiments suggests that 30 cm of soil cover should
provide for adequate rooting and minimal susceptibility to drought in most
instances (GAI Consultants 1979). However, the study also indicated that
increased soil cover thickness will be required where:
• The soil is capable of holding limited amounts of
available moisture (e.g., highly sandy or clayey soils).
• Slope gradients are steep and rapid drainage produces
droughty conditions.
• The climate is marked by severe deficiency of moisture
during the growing season.
In contrast to the review by GAI Consultants (1979), Hodgson et al. (1963)
indicated that 60 cm of soil fertilized at normal rates was required to obtain
satisfactory plant growth. Furthermore, Dvorak et al. (1979) reported that
vegetation growing on a 60-cm mantle of subsoil placed over acidic coal refuse
was able to survive a five-week drought better than vegetation growing on 15-
or 30-cm deep sgbsoil mantles.
On the basis of this limited research, it appears that at least 60 cm of
soil is required to sustain plant growth; this soil depth is often mentioned
in reclamation plans. Many states (for example, Arizona, Florida, Illinois,
Kentucky, Missouri, Montana, Pennsylvania, Oklahoma) have solid waste-handling
regulations that require a minimum of 60 cm of soil cover. If borrow pits are
necessary to obtain cover materials, larger areas could be impacted.
Ill
-------
VEGETATION ESTABLISHMENT
[120-127]
Once the optimal soil mantle thickness for a given storage site has been
determined, the plant species adapted to the climatic and predicted edaphic
conditions of the site should be identified and candidate species for revege-
tation selected. The practices appropriate for the preparation and seeding of
the soil-covered storage site can then be determined. Plants should be selec-
ted that provide short- and long-term cover. The ultimate long-term cover
should provide the percent cover required to control erosion. This can be
determined by use of the USLE (Equation 4).
Plant Species Selection
The species selection process should begin with an examination of native
species occurring at the proposed storage site. These native species and
plant community types are adapted to the site's existing environmental condi-
tion and can probably survive the environmental conditions of the developed
storage facility. Each plant species has its own growth characteristics that
determine its value in stabilizing soil for reclamation (Mills and Char 1976).
Information should then be gathered describing the characteristics (e.g.,
environmental requirements, agronomic uses, performance in field tests) that
may be used to determine the capability of that species to grow in the new
"habitat" of the soil-covered storage facility. The habitat created on the
storage site will be a function of local climatic conditions, soil types used
in the soil mantle, and storage-site design.
There will often be cases when seeds, cuttings, or containerized plant-
ings of native vegetation will not be available, or prohibitively expensive,
and other plant species will have to be selected (GAI Consultants 1979).
Plant species useful in the revegetation of buried coal combustion wastes are
listed in Appendix C.
In reviewing the species selected for revegetating a waste-storage site,
the reader may wish to determine whether the species chosen meet the following
criteria (Mills and Char 1976; GAI Consultants 1979):
• Able to withstand the erosive and traffic stresses pre-
sented at the storage site.
• Adaptable to storage-site soil conditions (i.e., pH,
moisture, texture, and fertility).
• Adaptable to climatic conditions (i.e., sunlight exposure,
temperature, wind exposure, and precipitation) at the
site.
• Resistant to insect damage and disease.
• Compatible with other plants selected for use.
• Compatible with post-closure land use.
112
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• Able to propagate themselves (either vegetatively or by
seed).
• Able to provide good surface coverage.
• Somewhat tolerant of the constituents of the buried wastes
(e.g., tolerant of saline or alkaline conditions; resis-
tant to the effects of boron)
Cover Soil Placement
After the deposited waste materials have been graded to final contour,
the soil mantle should then be placed. Most blade-type machinery may be used
to spread the soil cover. The major concern in this stage of reclamation is
to monitor the degree of compaction that occurs within the soil mantle during
placement (GAI Consultants 1979). For successful plant establishment, a dry
bulk density of the soil mantle in the range of 1.2 to 1.6 g/cm3 is recom-
mended.
Seedbed Preparation
Following application of the soil mantle over the surface of the depos-
ited waste materials, the soil should be prepared for planting as quickly as
possible. The nutrient status, pH, and bulk density of the soil should be
determined (GAI Consultants 1979), and appropriate amounts of fertilizer and
lime applied to the soil cover. If the soil cover has been severely compacted
during placement, the soil can be loosened by scarification or tillage. Disc
harrowing to a depth of 15 to 25 cm mixes amendments into the cover soil and
will prepare the soil surface for planting.
Seedi ng
Once the seedbed has been prepared, one or more methods of planting vege-
tation should be identified. Currently used methods of establishing vege-
tation and their specific suitability include (Mills and Char 1976):
Broadcasting, in which seed is dispersed by a fly wheel mechanism as
the seed falls from a container. Uniform distribution is difficult
on sloping areas or areas difficult to traverse with planting
equipment.
Seed drilling, in which seed placement (distribution and planting
depth) is ensured. This is the preferred method for establishing
herbaceous vegetation, but use is limited to rolling or level
terrain that is relatively free of stones; it cannot be used on
slopes greater than 3:1.
113
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Hydro-seeding, which is commonly used for seeding disturbed areas.
Application of seed and possibly fertilizers and mulch is made by
spraying a slurried mixture over the surface. It is useful in
seeding steep outslopes and other areas where equipment accessi-
bility is limited.
Hand planting, which is used when trees or, more likely, shrubs are
planted as bare-root stock or tublings.
Mulchi ng
Mulching is required to protect the newly seeded area from erosion during
and immediately following germination. In addition, mulching provides a
better environment for germination and plant development by increasing soil
moisture, moderating soil temperature, and increasing soil organic matter
content. The mulch should be "crimped" into the soil surface soon after
application to prevent the loss of mulch by wind and water. County agri-
cultural extension agents can aid in determining appropriate mulch application
rates.
POSTRECLAMATION LAND USE AND MANAGEMENT [129]
It will be difficult to identify the land use appropriate for a given
reclaimed storage site prior to its construction and ultimate closure. How-
ever, a statement describing the potential land-use categories (Table 23) for
which a storage site is being considered should be included in the reclamation
plan because the proposed end use of a storage site will influence both the
reclamation methods and the vegetation species employed.
Postreclamation site management includes all efforts to perpetuate vege-
tation established on the site and maintain the physical integrity of the
site, thus preventing exposure and subsequent dispersal of waste materials.
The major emphasis of reclaimed waste-site management can be classified as:
~ Monitoring environmental and site conditions
• Site maintenance
The degree of postreclamation maintenance required at a storage site will
largely depend upon the proposed land use of the reclaimed site, method of
waste placement, and federal and state regulations (GAI Consultants 1979).
Immediately following revegetation, data should be gathered describing
germination and early growth of vegetation. Decisions can then be made as to
the need for additional fertilization, reseeding, or irrigation. Periodic
measurement of plant density and/or plant cover over several growing seasons
will indicate the success of revegetation. Additional observations should be
made to estimate the suitability of the revegetated area for wildlife.
114
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Table 23. Potential Land-Use Categories for
Coal Combustion Waste-Storage Sites3
Possible site use
after closure
Requi rements
Wildlife habitat, wilderness
Limited agriculture or
recreation:
Grazing
Hunting
Developed agriculture or
recreation:
Cropland
Athletic fields
Golf courses
Light commercial and
industrial development:
Warehouse
Shopping plaza
Parking lot
Materials storage lot
Light industry
Adequate cover and vegetation.
Adequate cover and vegetation; added pro-
tection of fill or embankment slopes to
prevent erosion resulting from animal or
vehicle traffic; maintenance of vegetation.
Possible increase in soil cover depth;
management and maintenance of vegetation;
stable underlying waste; possible increased
erosion control to prevent exposure of
waste.
Stable underlying ash capable of foundation
support (where required); increased erosion
control and drainage considerations; manage-
ment and maintenance of vegetation.
Source: GAI Consultants (1979).
Site maintenance includes required upkeep and other work identified as
necessary by the monitoring program. Operations necessary to maintain the
integrity of the storage site include:
• Repair of fences surrounding the site
* Maintenance and clearing of water drainage pathways and
erosion control structures
Upkeep of access roads and earth embankments
115
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INFORMATION REQUIREMENTS AND SOURCES
The following is a list of information required to carry out an analysis of
reclamation of waste-storage sites as discussed in this chapter. The most
likely sources of this information are also identified.
Information required
Sources
Local climatological data:
Range of temperature
Amount of precipitation
Intensity of precipitation
Facility operator
Natl. Weather Service
Vegetation survey:
Plant species of site
Plant community types adapted to local
climatic and edaphic conditions
Facility operator
Site visit
Field offices of Soil
Conservation Service
State Department of
Natural Resources
Soil survey:
Soil types
Spatial distribution across site
Facility operator
Field offices of Soil
Conservation Service
Agricultural Extension
Service
Soil analyses:
Soil texture
Soil fertility
Soil pH
Facility operator
Field offices of Soil
Conservation Service
Soil survey reports
Agricultural Extension
Service
116
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Chapter 12
Sources of Current Information
This chapter presents sources of current information on combustion waste
production, waste handling, applicable regulations, reclamation, and fish and
wildlife resources. Approaches to environmental assessment are being de-
veloped by a number of the agencies listed below, and these may prove useful
to the reader as supplements or more sophisticated substitutes for the ap-
proach outlined in this manual. Researchers are expanding the data base for
toxicological effects of combustion waste materials. Several of the agencies
listed here are sponsoring such research and can serve as sources of ongoing
research. To maintain a current knowledge of toxicological effects, one must
keep up with the current literature. Journals that are likely to carry perti-
nent articles include:
Archives of
Builetin
Environmental Health
of Environmental
Contamination and Toxicology
Envi ronmental Health Perspectives
Environmental Pollution
Environmental Science and Technology
Journal of Environmental Quality
Minerals
5oH
and
Science
the Environment
Water, Air, and Soil Pollution
Water Research
Water Resources Bulletin
Water Resources Research
This list of sources is not exhaustive but is provided to serve as a starting
point for acquiring information. Appropriate state and local agencies can be
identified by consulting the appropriate regional offices listed below or the
Conservation Directory.
PUBLICATIONS
Conservation Directory, published annually by the National Wildlife Founda-
tion"^ 1412 16th St. NW, Washington, DC 20036. Telephone: (202) 797-6800.
Energy Users Report, published weekly by the Bureau of National Affairs,
Washington, DC 20037. Telephone: (202) 452-4200.
117
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Environment Reporter, published weekly by the Bureau of National Affairs,
Washington, DC 20037. Telephone: (202) 452-4200.
EPRI Journal, published monthly by Electric Power Research Institute, P.O.
Box 10412, Palo Alto, California 94303. Telephone: (415) 855-2000.
Federal Register, published daily during the working week by the Office of the
Federal Register, National Archives and Records Service, General Services
Administration, Washington, DC 20408. Telephone: (202) 523-5227.
Inside EPA Weekly Report, published weekly by Inside Washington Publishers,
P.O. Box 7167, Ben Franklin Station, Washington, DC 20044. Telephone: (202)
347-3976.
FEDERAL AGENCIES
Regional Offices of the U.S. Environmental Protection Agency
Region I
Jonn F. Kennedy Federal Building
Boston, Massachusetts 02203
Connecticut, Maine, Massachusetts,
New Hampshire, Rhode Island, Vermont
Region II
26 Federal Plaza
New York, New York 10007
New Jersey, New York, Puerto Rico,
Virgin Islands
Region III
6tfi and Walnut Streets
Philadelphia, Pennsylvania 19106
Delaware, District of Columbia,
Maryland, Pennsylvania,
Virginia, West Virginia
Region IV
34b Courtland Street, N.E.
Atlanta, Georgia 30308
Alabama, Florida, Georgia, Kentucky,
Mississippi, North Carolina, South
Carolina, Tennessee
Region V
230 S. Dearborn Street
Chicago, Illinois 60604
Illinois, Indiana, Michigan,
Minnesota, Ohio, Wisconsin
Region VI
1201 Elm Street
Dallas, Texas 75270
Arkansas, Louisiana, New Mexico,
Oklahoma, Texas
Region VII
1735 Baltimore Street
Kansas City, Missouri 64108
Iowa, Kansas, Missouri, Nebraska
Region VIII
1860 Lincoln Street
Denver, Colorado 80203
Colorado, Montana, North Dakota,
South Dakota, Utah, Wyoming
Region IX
100 California Street
San Francisco, California 94111
Arizona, California, Hawaii, Nevada,
Pacific Trust Territories
Region X
1200 6th Avenue
Seattle, Washington 98101
Alaska, Idaho, Oregon, Washington-
118
-------
State Offices of the U.S. Soil Conservation Service
Alabama
Soil Conservation Building
P.O. Box 311
Auburn, Alabama 36830
Alaska
Severns Building
P.O. Box F
Palmer, Alaska 99645
Arizona
230 N. 1st Avenue
6029 Federal Building
Phoenix, Arizona 85025
Av^ancac
Federal Office Building
Room 5401
Little Rock, Arkansas
California
Tioga Building
2020 Mil via Street
Berkeley, California 94704
Colorado
12417 Federal Building
Denver, Colorado 80202
Connecticut
Mansfield Professional Building
Storrs, Connecticut 06268
Delaware
501 Academy Street
P.O. Box 418
Newark, Delaware 19711
Florida
Federal Building
P.O. Box 1208
Gainesville, Florida 32601
Georgia
Old Post Office Building
P.O. Box 832
Athens, Georgia 30601
Hawaii
440 Alexander Young Building
Honolulu, Hawaii 96813
Idaho
5263 Emerald Street
P.O. Box 38
Boise, Idaho 83707
Illinois
Federal BuiIding
200 W. Church Street
P.O. Box 678
Champaign, Illinois 61820
Indiana
311 West Washington Street
Indianapolis, Indiana 46204
Iowa
693 Federal Building
Des Moines, Iowa 50209
Kansas
760 South Broadway
P.O. Box 600
Salina, Kansas 67401
Kentucky
1409 Forbes Road
Lexington, Kentucky 40505
Louisiana
3737 Government Street
P.O. Box 1630
Alexandria, Louisiana 71301
119
-------
Maine
USDA Building
University of Maine
Orono, Maine 04473
Maryland
4321 Hartwick Road
College Park, Maryland 20740
Massachusetts
27-29 Cottage Street
Amherst, Massachusetts 01002
Michigan
1405 South Harrison Road
East Lansing, Michigan 48823
Minnesota
200 Federal Building
316 North Robert Street
St. Paul, Minnesota 55101
Mississippi
Milner Building, Room 490
P.O. Box 610
Jackson, Mississippi 39205
Missouri
601 West Business Loop 70
P.O. Box 459
Columbia, Missouri 65201
Montana
Federal Building
P.O. Box 970
Bozeman, Montana 59715
Nebraska
134 South 12th Street
Lincoln, Nebraska 68508
Nevada
Room 234
U.S. Post Office Building
P.O. Box 4850
Reno, Nevada 89505
New Hampshire
Federal Building
Durham, New Hampshire 03824
New Jersey
1370 Hamilton Street
P.O. Box 219
Somerset, New Jersey 08873
New Mexico
517 Gold Avenue, S.W.
P.O. Box 2007
Albuquerque, New Mexico 87103
New York
Midtown Plaza, Room 400
700 East Water Street
Syracuse, New York 13210
North Carolina
1330 Saint Marys Street
P.O. Box 12045
Raleigh, North Carolina 27605
North Dakota
Federal Building
P.O. Box 1458
Bismarck, North Dakota 58501
Ohio
200 N. High Street
Room 526
Columbus, Ohio 43215
Oklahoma
Agriculture Center Building
Farm Road and Brumley Street
Stillwater, Oklahoma 74074
120
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Oregon
Washington Building
1218 S.W. Washington Street
Portland, Oregon 97205
Pennsylvania
Federal Bldg. and Court House
Box 985
Harrisburg, Pennsylvania 17101
Puerto Rico
G.P.O. Box 4868
Santurce Station
San Juan, Puerto Rico 00936
Rhode Island
Soil Conservation Service
East Greenwich,
Rhode Island 02818
South Carolina
Federal Building
901 Sumter Street
Columbia, South Carolina 29201
South Dakota
239 Wisconsin Avenue, S.W.
P.O. Box 1357
Huron, South Dakota 57350
Tennessee
561 U.S. Court House
Nashville, Tennessee 37203
Texas
16-20 South Main Street
P.O. Box 648
Temple, Texas 76501
Utah
4012 Federal Building
125 South State Street
Salt Lake City, Utah 84111
Vermont
19 Church Street
Burlington, Vermont 05401
Virginia
Federal Building, Room 7408
400 N. 8th Street
P.O. Box 10026
Richmond, Virginia 23240
Washington
360 U.S. Courthouse
W. 920 Riverside Avenue
Spokane, Washington 99201
West Virginia
209 Prairie Avenue
P.O. Box 865
Morgantown, West Virginia 26505
Wisconsin
4601 Hammersley Road
P.O. Box 4248
Madison, Wisconsin 53711
Wyoming
Tip Top Building
345 East 2nd Street
P.O. Box 340
Casper, Wyoming 82602
121
-------
State Offices of the Bureau of Land Management
Alaska
Bureau of Land Management
701 C Street
Box 13
Anchorage, Alaska 99513
Arizona
Bureau of Land Management
2400 Valley Bank Center
Phoenfx, Arizona 85073
California
Bureau of Land Management
Federal Building
Sacramento, California 95825
Colorado
bureau of Land Management
Colorado State Bank Building
Denver, Colorado 80202
Eastern States
Bureau of Land Management
7981 Eastern Avenue
Silver Spring, Maryland 20910
Idaho
Bureau of Land Management
Federal Building
Boise, Idaho 83724
Montana
Bureau of Land Management
Granite Tower Building
222 N. 32nd Street
Billings, Montana 59101
Nevada
Bureau of Land Management
Federal Building
Reno, Nevada 89509
New Mexico
Bureau of Land Management
Federal Building
Santa Fe, New Mexico 87501
Oregon
Bureau of Land Management
729 NE Oregon Street
Portland, Oregon 97208
Utah
Bureau of Land Management
University Club Building
136 E. South Temple Street
Salt Lake City, Utah 84111
Wyomi ng
Bureau of Land Management
Federal Building
Cheyenne, Wyoming 82001
122
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Regional Offices of the Office of Surface Mining Reclamation and Enforcement
Region I
1st Floor, Thomas Hill Bldg.
950 Kanawha Blvd. East
Charleston, West Virginia 25301
Maine, New Hampshire, Vermont,
Massachusetts, Rhode Island,
New York, Connecticut, New Jersey,
Maryland, Pennsylvania, Delaware,
West Virginia, Virginia
Reqion II
530 Gay St. SW
Suite 500
Knoxville, Tennessee 37902
Kentucky, Tennessee, North Carolina,
South Carolina, Georgia, Florida,
Alabama, Mississippi
Region IV
Scarritt Bldg.
818 Grand Ave.
Kansas City, Missouri 64106
Iowa, Missouri, Nebraska, Kansas,
Oklahoma, Arkansas, Texas,
Louisiana
Region V
Brook Towers
1020 15th St.
Denver, Colorado 80205
North Dakota, South Dakota, Montana,
Wyoming, Colorado, Utah, Arizona,
Nevada, California, Idaho, Oregon,
Washington, Alaska, Hawaii,
New Mexico
Region III
Federal Bldg., U.S. Courthouse
Room 510
46 E. Ohio St.
Indianapolis, Indiana 46204
Ohio, Indiana, Illinois, Michigan,
Wisconsin, Minnesota
123
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Offices of the U.S. Fish and Wildlife Service
Region I
U.S. Fish and Wildlife Service
Lloyd 500 Building, Suite 1692
500 N.E. Multnomah Street
Portland, Oregon 97232
Region II
U.S. Fish and Wildlife Service
P.O. Box 1306
Albuquerque, New Mexico 87103
Region III
U.S. Fish and Wildlife Service
Federal Building
Fort Snelling
Twin Cities, Minnesota 55111
Region IV
U.S. Fish and Wildlife Service
17 Executive Park Drive, N.E.
P.O. Box 95067
Atlanta, Georgia 30347
Region V
U.S. Fish and Wildlife Service
One Gateway Center, Suite 700
Newton Corner, Massachusetts 02158
Region VI
U.S. Fish and Wildlife Service
P.O. Box 25486
Denver Federal Center
Denver, Colorado 80225
Eastern Energy and Land Use Team
Office of Biological Services
U.S. Fish and Wildlife Service
Route 3, Box 44
Kearneysville, West Virginia 25430
Western Energy and Land Use Team
Office of Biological Services
U.S. Fish and Wildlife Service
2625 Redwing Road
Fort Collins, Colorado 80526
124
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Bovee, K.D., and T. Cochnauer. 1977. Development and Evaluation of Weighted
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Gough, L.P., H.T. Shacklette, and A.A. Case. 1979. Element Concentrations
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129
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Appendix A
English/Metric Equivalents
Multiply
By
To obtain
Acres
0.4047
Hectares (ha)
Acre-feet
1.2335 x 103
Cubic meters (m3)
British thermal units
[(Btu) thermochemical]
1.0544 x 103
Joules (J)
British thermal
units/pound (Btu/lb)
2.324 x 103
Joules/kilogram (J/kg)
Calories (cal)
4.18
Joules (J)
Cubic feet (ft3)
0.0283
Cubic meters (m3)
Degrees Fahrenheit (°F)
- 32
5/9
Degrees Celsius (°C)
Feet (ft)
0.3048
Meters (m)
Gallons (gal)
3.7854
Liters (L)
Gallons (gal)
0.0038
Cubic meters (m3)
Gallons/minute (gal/min)
0.0631
Liters/second (L/s)
Gallons/minute (gal/min)
6.309 x 10-5
Cubic meters/second (m3/s)
Inches (in.)
2.540
Centimeters (cm)
Kilowatt-hours (kWh)
3.60 x 106
Joules (J)
Miles (mi)
1.6093
Kilometers (km)
Pounds (lb)
0.4536
Kilograms (kg)
Square feet (ft2)
0.0929
Square meters (m2)
Square miles (mi2)
2.590
Square kilometers (km2)
Tons, short (t)
9.0718 x 102
Kilograms (kg)
Tons, short (t)
0.9072
Tons, metric (MT)
131
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Appendix B
Glossary
The technical terms selected for the Glossary are mainly terms that may not
ordinarily be familiar to biologists. The definitions provided are those
applicable to the subject matter of this report.
ACID MINE DRAINAGE - Acidic seepage from mines in which the spoil is high in
pyrite (FeS); when oxidized in the presence of water, pyrite yields
sulfuric acid.
AGGREGATE (BOILER) - That part of residual combustion solids that has fused
into particles heavy enough to drop out of the furnace gas stream.
AQUIFER - A permeable unit of rock or sediment from which groundwater can be
extracted. Confined aquifers are bounded on top and bottom by imperme-
able materials. Unconfined aquifers are bounded on top by a water table.
ASH (COAL) - The solid material remaining after coal is burned. Contains most
of the mineral and inorganic material originally present in the coal.
AVAILABLE ELEMENTS (SOIL) - Chemical elements in a soil that are in a form
capable of assimilation by plants. May comprise only a portion of the
total amount of the element present in that soil.
BAG HOUSE - A series of filters to remove particles from the flue gases.
BERM - A bench of soil or rock built on an earthen structure. It may serve
various purposes such as a dike, an encasement for a drainage system, a
weight for structural stabilization of an embankment, or an erosion-
control structure.
BOTTOM ASH - Dry ash from coal combustion that does not melt but is too heavy
to be entrained in the flue gas. Also called cinders.
BUFFERING CAPACITY - A measure of the tendency of a soil or water to resist
large changes in pH.
BULK DENSITY (SOIL) - The weight per unit volume of soil. Agricultural soils
have bulk densities usually between 1.2 and 1.7 g/cm3. A compacted clay
may have a bulk density of 2 g/cm3.
CATION EXCHANGE CAPACITY (CEC) - The relative adsorptive power of a soil for
cations. Expressed as the number of milliequivalents of cations per
100 grams of dry soil.
133
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CLARIFLOCCULATOR - A device for handling dilute suspensions to produce a
relatively clear supernatant liquid (overflow) and an agglomeration of
settleable or filterable solids that are withdrawn at the bottom of the
device (underflow). It consists of a tank, a means for introducing the
feed suspension, a drive-actuated rake mechanism for moving settled
solids to a discharge point, a means for removing the thickened solids,
and a means for removing the clarified liquor. Chemicals may be added to
the feed to enhance the physical separation.
CLAY LINER (WASTE DISPOSAL) - A liner consisting of a compacted layer of a
clay with a low hydraulic conductivity.
CODE OF FEDERAL REGULATIONS (CFR) - A codification of all executive and admin-
istrative rules and regulations having general applicability and legal
effect issued by the administrative agencies of the federal government.
CONSUMPTIVE USE (WATER) - That portion of water taken into a power plant that
is not directly returned to the surface water body. The water is lost
through evaporation and seepage.
DEWATERING (SLURRY) - The process of removing water from a slurry. Processes
include natural evaporation, centrifugation, decantation, and filtration.
ELECTROSTATIC PRECIPITATOR - A device used to remove particles from flue
gases, by charging the particles electrically and collecting them on
appropriate electrodes.
FIXATIVE (FOR FGD SLUDGE) - A chemical additive that is mixed with FGD sludge
to give it more desirable properties for disposal. Commonly, a fixative
is used to lessen the thixotropic characteristics of the sludge.
FLOODPLAIN - The portion of a river or stream valley that is periodically
inundated during episodes of excessive runoff. The solid waste-disposal
regulations (40 CFR, Part 257) use the term "floodplain" to refer to the
100-year floodplain. The 100-year floodplain is the area that is likely
to be inundated once in one hundred years.
FLOW, AVERAGE ANNUAL - The average volume of water to pass a given cross
section of a stream during a given year. Usually expressed in units such
as cubic feet per second (cfs).
FLOW, 7-DAY/10-YEAR LOW FLOW - The lowest volume af flow statistically ex-
pected to pass through a given cross section of a stream during a 7-day
timespan in any 10-year period.
FLUE-GAS DESULFURIZATION (FGD) - Any process used to remove sulfur (largely
sulfur oxides) from flue gases.
FLUSHING TIME (IMPOUNDMENT) - The period of time required to completely re-
place the volume of water in an impoundment through natural processes.
FLY ASH - That portion of the coal ash carried up the flue.
134
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FUGITIVE DUST - Particles of dust removed from a surface by the wind.
GROUNDWATER - The water contained within the pore spaces of rock or soil.
HEAT RATE - Efficiency of conversion of boiler heat energy to electrical
energy--e.g., if X amount of boiler heat is needed to produce Y amount of
electricity, heat rate is X Btu/Y kWh.
HEATING VALUE - Amount of heat released per weight of coal during combustion.
HIGH-SULFUR COAL - In general, coal that contains over 1% sulfur. In some
instances, however, it is defined as coal containing over 3% sulfur.
HYDRAULIC CONDUCTIVITY - The velocity at which water can flow through a perme-
able material.
HYDRAULIC GRADIENT - The change in hydraulic head over distance. Nearly
horizontal flow has a very small gradient.
HYDRAULIC HEAD - The energy that allows water to flow. It consists of a
pressure and a height component. Water flows from areas of higher to
lower head.
IMPERMEABLE LINER (WASTE DISPOSAL) - Material placed on the bottom and sides
of a waste impoundment to contain the waste material. No liner is com-
pletely impermeable, but many of the synthetic materials are relatively
impermeable compared to natural earth liners.
INFILTRATION RATE (SOIL) - The rate at which water enters the surface layer of
soil.
ISOERODENTS - Lines of equal values of R (rainfall and runoff factor) in the
Universal Soil Loss Equation.
LEACHATE - Water and dissolved constituents draining out of a given column of
saturated porous material such as soil.
LEACHING - The process of moving dissolved constituents (usually by water)
downward through a column of porous material such as soil.
MINE-MOUTH - Operations such as coal washing and power generation carried out
adjacent to the coal mine.
ORGANIC MATTER (SOIL) - The amount of plant and animal residues in a soil.
Soils typically contain about 1 to 6% organic matter.
PERMEABILITY (SOIL) - The quality of a soil that enables it to transmit water
or air. It is not equivalent to infiltration rate (see INFILTRATION
RATE).
135
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PERMEABILITY CLASSES (SOIL) -
Hydraulic conductivities
(inches/hour) (centimeters/second) (meters/day)
Very slow
< 0.05
<
3.5
X
10s
< 0.006
Slow
0.05 - 0.20
3.5 x
10s
-
14 x 105
0.006 - 0.023
Moderately slow
0.20 - 0.80
X
H
105
-
56 x 105
0.023 - 0.046
Moderate
0.80 - 2.50
X
ID
LO
105
-
176 x 105
0.046 - 0.289
Moderately rapid
2.50 - 5.00
176 x
105
-
352 x 10s
0.289 - 0.578
Rapid
5.00 - 10.00
352 x
10s
-
704 x 105
0.578 - 1.156
Very rapid
> 10.00
>
704
X
105
> 1.156
PIPING - A progressive failure of a dike or embankment that occurs when a
seepage velocity is great enough to cause internal erosion.
PLANT CAPACITY (RATED CAPACITY) - Nominal capacity for the power output by a
electric generating unit, usually expressed in kilowatts or megawatts.
PLANT FACTOR - Ratio of electricity generated during a year to the electricity
that could have been generated if the plant operated at nominal capacity
for the entire year.
PLUME (WATER) - A stream of water that enters an existing body of water and is
still distinguishable because of differences between the influent water
and the receiving water in such factors as velocity, chemistry, or tem-
perature. A plume dissipates with dilution and dispersion.
POINT SOURCE (WATER) - A single source of pollutant discharge to surface
waters.
POZZOLANIC - Pertaining to a material that becomes cementlike after exposure
to water.
RECLAMATION - Usually implies the restoration of disturbed land to primary
production.
RUNOFF (RAINFALL) - All rainfall (and snowmelt) that does not soak into the
ground, does not evaporate immediately, or is not used by vegetation.
This flows down slopes and forms streams.
136
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SCRUBBER SLUDGE (FGD) - Semisolid waste material, usually CaS03 and CaS04,
resulting from the removal of sulfur oxides from flue gases using lime,
limestone, or double-alkali techniques.
SEEPAGE - Any water or liquid effluent that flows through a porous medium.
This term is often used to refer to the liquid lost through the bottom of
a waste pond.
SLAG - That portion of the coal ash that melts to a viscous fluid at boiler
operating temperatures, and cools to a glassy, angular material.
SLURRY - Any mixture of water and finely divided solids. Can refer to mix-
tures of coal and water (coal slurry), ash and water (ash slurry), desul-
furization sludge and water (scrubber slurry), or coal refuse and water
(refuse slurry).
SPLIT FACTOR - Percentage of ash that becomes entrained in flue gas as fly
ash.
STEAM-ELECTRIC POWER PLANT - A power plant that generates electric power
through steam-driven turbines. In commercial power plants, the fuel used
to produce steam from water can be coal, oil, natural gas, or enriched
urani um.
TEXTURE (SOIL) - The proportion of sand, silt, and clay in a soil. Soil
texture is expressed in terms such as "sandy loam", "clay", "silty clay
loam", etc.
THIXOTROPIC - Having the property of liquefying when disturbed and returning
to the solid phase upon standing undisturbed.
THROW-AWAY SYSTEM (FGD) - A system in which the waste product from flue-gas
desulfurization is not recycled or reclaimed, but instead is disposed of
as waste.
TRACE ELEMENTS - Chemical elements that normally are present in minute (trace)
quantities. Includes metals such as chromium, zinc, cadmium, and copper,
and nonmetals such as selenium, boron, and arsenic.
UNDERFLOW (CLARIFIER) - The stream of coarse particles that are separated by a
clarifier or cyclone (see also CLARIFLOCCULATOR).
UNSATURATED FLOW - Flow of a liquid through a porous medium in which some of
the pore space is occupied by air. Unsaturated flow is usually slower
than saturated flow under the same conditions.
VACUUM DISK FILTER - A continuous rotary vacuum filter made up of filter disks
mounted at regular intervals around a hollow center shaft covered with a
cloth filter. The device is used for dewatering sludge or solids by
application of a vacuum inside the disks. A layer of caked solids (fil-
ter cake) is formed on the outer filter surface, and is subsequently
removed.
137
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WATER-HOLDING CAPACITY (SOIL) - The total amount of water capable of being
held in a soil by capillary forces. Usually expressed as percent by
weight of dry soil.
WATERSHED - An area, usually a valley or collection of valleys, surrounded by
surface-water divides. All precipitation falling into a watershed sup-
plies runoff to the same stream.
WATER TABLE - The surface that separates the groundwater in an unconfined
aquifer (an aquifer not bounded on top by an impermeable layer) from the
unsaturated zone above it (see AQUIFER).
138
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Appendix C
Species of Vegetation Appropriate for Revegetating Waste-Storage Sites
The selection of plant species for use in the revegetation of buried coal
combustion wastes is extremely difficult, because little effort has been made
to identify species appropriate for this purpose. To date, no large-scale
reclamation of these wastes has been attempted in the United States. This
section can therefore only identify plant species that may be suitable for the
revegetation of these wastes, based upon the performance of these species in
the reclamation of other types of covered or buried anthropogenic waste.
Specifically, those species used to successfully revegetate coal mining wastes
and mineral tailings were considered. Table C.l is a list of plant species
adaptable to a wide range of soil pH, fertility, salinity, and other physical
and environmental conditions.
Because the vegetation planted on burial sites for coal combustion wastes
will not be growing directly on the waste material, species-selection criteria
will be based primarily upon both the chemical and physical characteristics of
the soil mantle placed over the wastes and the site-specific considerations^
precipitation, topography, and climate. Roots of plants growing over buried
combustion wastes will, however, be in contact with the wastes either atthe
interface between the soil mantle and the wastes or by root penetration into
the waste material. Some tolerance to the acidic or alkaline nature of the
waste material is therefore desirable. In many instances, subsoil will be
used to form the mantle, requiring the use of plants adapted to harsh, low-
fertility conditions. If topsoil is segregated during waste-site construction
and then reapplied over the waste material, species adapted to very different
soil conditions will be needed.
139
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Table C.l. Plant Species Potentially Useful in the Revegetation of
Buried Coal Combustion Wastes3
Common name
Scientific name
• b
Species
origin
Region of use
in United States
Comments
Grasses and Legumes
A1 fal fa
Alkali sacaton
Bahia grass
Barley
Bentgrass
Bermuda grass
Big bluestem
Birdsfoot trefoil
Blackseed needlegrass
Buffalograss
Buffel grass
Medicago sativa
Sporobolus airoides
Paspalum notatum
Hordeum vulgare
Agrostis spp.
C.ynodon dactyl on
Andropogon gerardi
Lotus corniculatus
Stipa avenacea
Buchloe dactyloides
Cenchris ciliaris
m
N
N
East, Midwest, West
West
Southeast
Northeast, Southwest
East
Southeast, Southwest
East, Midwest, West
East, Midwest
West
Midwest, West
Southeast, Southwest
Legume; good growth in dry
regions; high boron toler-
ance.
Recommended for dry regions;
well adapted to moderately
alkaline and saline condi-
tions.
Recommended for warmer cli-
mates; volunteer on alkaline
limestone strip mine spoil.
Annual species; yields fast
cover; good growth on alka-
line and saline soils.
Semi tolerant of growth on
fly ash; some strains toler-
ant of high soil A1, Cu, Fe,
and Zn concentrations.
Recommended for dry regions
and saline soils.
Strong, deep-rooted, with
short underground stems;
effective in controlling
erosion.
Legume; salt tolerant; good
growth on soil with pH 4.0
or greater.
Good for loam or heavier
soils with > 33 cm precipi-
tation per year.
Drought-tolerant; withstands
alkaline soils but not sandy
ones; will regenerate if
overgrazed.
Good growth on alkaline and
saline spoils.
(continued)
-------
Table C.l. (Continued)
Common name
Scientific name
Species'3
origin
Region of use
in United States
Comments
Grasses and Legumes (contd.)
Canada bluegrass Poa compressa
Caucasian bluestem
Cicer milkvetch
Clover
Crownvetch
Deertongue
Field brome
Flat pea
Foxtail millet
Gramma grass
Dothriochloa caucasica
Astragalus cicer
Trifolium spp.
Coronilla varia
Panicum clandestinum
Bromus arvensis
Lathyrus sylvestris
Setaria italica
Bouteloua spp.
Northeast, Northwest
Midwest, Northeast
West
East, Midwest, West
East, Midwest
Northeast
Northeast, Northwest
East, Northeast
Midwest, West
N West
(continued)
Does well on acid soils,
droughty soils, or soils too
low in nutrients to support
good stands of Kentucky
bluegrass.
Does well on moderately
acid, droughty sites.
Legume; adapted to dry condi-
tions; does well on alkaline
soils.
Legumes; tolerant of saline
and alkaline soils; adaptable
to dry conditions.
Legume; used extensively on
both moderately acid and
calcareous spoils; if seeded
with cover crop, may be use-
ful in erosion control; sup-
presses woody plant invasion.
Recommended for acid soils;
does not compete well with
other grasses; shade-
tolerant.
Good winter cover plant;
extensive fibrous root sys-
tem; annual; grows rapidly,
easy to establish.
Legume; recommended for acid
soils in cooler climates;
suppresses woody plant
invasion.
Requires warm weather during
growing season; cannot tol-
erate drought; good seedbed
preparation important.
Drought-resistant species.
-------
Tabl
Common name
Scientific name
Grasses and Legumes (contd.)
Indiangrass Sorghastrum nutans
Indian ricegrass
Italian ryegrass
Kentucky bluegrass
Lespedeza
Little bluestem
Lovegrass
Oat
Oryzopsis hymenoides
Lolium multiflorum
Poa pratensis
Lespedeza spp.
Scizachyrium scoparium
Eraqrostis spp.
Avena sativa
Orchard grass
Dactyl is qlomerata
Perennial ryegrass
Lolium perenne
Prairie sandreed
Calamovilfa lonqifolia
C.l. (Continued)
Species'5
origin
Region of use
in United States
Comments
N
N
I
I
N/I
N
N/I
East
West
East, Midwest
Northeast, Midwest
Northeast
Northeast, Midwest
West
East, Midwest, West
East, Midwest, West
East, Midwest
Midwest, West
Good growth and vigor on some
acid spoils.
Adapted to arid and semi arid
regions.
Annual species; yields quick
cover; adaptable to pH as low
as 5.0.
Recommended for cooler cli-
mates, moderate-pH soils.
Legumes; adaptable to a wide
range of soil pH; good for
erosion control.
Slow to establish; good
growth on moderately acid
spoil.
Recommended for dry regions;
adapted to alkaline and
saline conditions.
Bunch-forming; good winter
cover plant; requires nitro-
gen for good growth.
Adapted to moderate-pH soils
(pH 6-8); good for western,
high-altitude sites.
Highly adaptable to moder-
ately acid and alkaline
sites; can be developed for
pasturelands; does well in
mixtures with native grasses;
good for rapid stabilization
of soil and erosion control.
Tall, drought-tolerant; can
be used on sandy sites; rhi-
zomatous; seed availability
poor.
(conti nued)
-------
Common name Scientific name
Grasses and Legumes (contd.)
Redtop Agrostis alba
Reed canarygrass
Rye
Sand dropseed
Sheep sorrel
Smaller seabeach grass
Smooth brome
Switchgrass
Tall fescue
Tall oatgrass
Phalaris arundinacea
Secale cereale
Sporobolus cryptandrus
Rumex acetosella
Panicum amarum
Bromus i nermi s
Panicum virqatum
Festuca arundinacea
Arrhenatherum elatius
C.l. (Continued)
Species
origin
Region of use
in United States
Comments
Northeast, Midwest
East, Midwest
Northeast, Southwest
West
East
East
East, Midwest, West
East, Midwest
East, Midwest, West
East, Midwest, West
Useful for erosion control;
good on extremely harsh
spoil; recommended for cooler
eastern climates.
Highly adaptable to moderate
acid sites; can be developed
for pasturelands; does well
in mixtures with native
grasses.
Annual species; yields fast
cover for erosion control
during initial vegetative
establishment.
Recommended for desert areas.
Root sprouting perennial;
produces better cover than
grasses on low-fertility
soils; weedy plant; no
seeds available.
Good on very sandy, droughty
sites.
Good for rapid stabilization
and erosion control; fairly
drought-res i stant.
Drought-tolerant; good growth
on low-fertility soil; adapt-
able to wide soil pH range.
Shade-tolerant; does well in
mixtures with other grasses.
Short-lived perennial bunch-
grass, maturing early in the
spring; less heat tolerant
than orchard grass except in
Northeast; good on sandy and
shallow shale sites.
(continued)
-------
Table C.l. (Continued)
Common name
Scientific name
Species Region of use
origin in United States
Comments
Grasses and Legumes (contd.)
Timothy Phleum pratense
Western wheatgrass
Winter wheat
Shrubs
Big sagebrush
Black chokeberry
Bladder-senna
Blue paloverde
Bristly locust
Common matrimony-vine
Coral berry
Desert-willow
Agropyron smithii
Triticum aestivum
Artemisia tridentata
Pyrus melanocarpa
Colutea arborescens
Cercidium floridum
Robinia fertilis
Lycium halimi folium
Symphoricarpos orbiculatus N
Chilopsis linearis N
Northeast
West
Northeast, Midwest,
Southwest
West
Northeast
East
Southwest
East, Midwest
West
Midwest
Southwest
Good growth on soils with
pH 5.0 or higher.
Sod-forming, spreads rapidly,
slow germination; valuable
for erosion control; drought-
resi stant.
Annual species; tolerant to
high salt and low moisture;
may be good as cover crop
during initial vegetative
establi shment.
Adapted to growth on alkaline
soils; rapid growth; effec-
tive soil stabilizer.
Fairly good survival on acid
soi 1.
Nitrogen-fixing species;
does well under alkaline
conditions.
Drought-tolerant; will with-
stand alkaline conditions.
Nitrogen-fixing species; does
well on moderate pH soil;
good for erosion control.
Recommended for dry regions;
adaptable to alkaline and
saline conditions.
Good growth on spoil with
pH 5.0-6.5.
Withstands cold and drought;
excellent results on ferti-
lized saline-alkaline
tai1ings.
(conti nued)
-------
Table C.l. (Continued)
Common name
Scientific name
Species
origin
Region of use
in United States
Comments
Shrubs (contd.)
Elaeagnus
Gregg catclaw
Grease-wood
Hopbush
Honeysuckle
Indigobush
Japanese barberry
Saltbush
Rubber rabbitbrush
Scotch broon
Elaeagnus spp.
Acacia qreqgii
Sarcobatus verrciculatus
Dodonacea viscosa
Lonicera spp.
Amorptia fruticosa
Berberi s thunbergi i
Atriplex spp.
Chrysothainntis nauseosus
Cytisus scoparius
I East, Midwest, West
N Southwest
N West
N Southwest
N/I East, Midwest, West
N East, Midwest
I Southeast
N/I West
N West
Northeast, Midwest
Adaptable to a wide range of
soil pH; recommended for
saline conditions in arid
western climates; nitrogen
fixers.
Desert plant; with proper
management, adaptable to a
wide variety of soils.
Adapted for growth on saline-
alkaline soils in dry regions.
Aridk dry-country shrub;
resistant to cold; excellent
growth on saline-alkaline
copper tailings.
Does well on moderate pH
soils; poor results obtained
on wet, saline-alkaline
soils.
Acid-tolerant; prefers neu-
tral to slightly alkaline
soils; nitrogen fixer.
Tolerant of growth on alka-
line soil.
Arid, dry-country shrub; rec-
ommended for use on alkaline
and saline soils; drought-
resistant; varieties now
available.
Adapted to alkaline-saline
conditions; excellent growth
on Arizona copper tailings.
Very acid-tolerant; unable
to withstand Pennsylvania
and West Virginia winters;
poor choice for long-term
stands.
(continued)
-------
Common name
Scientific name
Shrubs (contd.)
Silver buffaloberry
Silky dogwood
Southern arrowwood
Sumac
Tree tobacco
Trees
Ash
Arizona sycamore
Austrian pine
Birch
Black cherry
Black locust
Shepherdia argentea
Cornus amomum
Viburnum dentatum
Rhus spp.
Nicotiana glauca
Fraxinus spp.
Platanus wrightii
Pinus nigra
Betula spp.
Prunus serotina
Robinia pseudoacacia
Black walnut
Juglans nigra
C.l. (Continued)
Species Region of use
origin in United States
N West
N Northeast
N East
N East, Midwest, West
N Southwest
Comments
Recommended for alkaline and
saline conditions on wet
soils; nitrogen fixer.
Does well on moderate pH
soil.
Good survival on moderately
acid spoil.
Eastern species are acid-
tolerant; species used in
West are adapted to alkaline
and saline conditions in dry
climates.
Excellent growth on ferti-
lized saline-alkaline
tai1i ngs.
N Northeast, Midwest
N Southwest
I Northeast, Midwest
N East
N Northeast, Midwest
N Northeast, Midwest
N Northeast, Midwest
Poor to good survival on mod-
erate pH soils.
Drought-tolerant.
Good survival on acid sites.
Good survival over a wide
range of soil pH.
Does fairly well on acid
embankments.
Nitrogen-fixing species; pro-
duces fast cover; good nurse
crop; excellent for erosion
control; susceptible to
insect attacks; good growth
on alkaline overburden.
Fair survival on moderately
acid soils; better growth
on calcareous spoils.
(continued)
-------
Table C.l. (Continued)
Common name
Scientific name
Species
origin
Region of use
in United States
Comments
Trees (contd.)
Eastern cottonwood
Eastern redbud
Eastern white pine
Eucalyptus
European black alder
Jack pine
-c*
--1 Larch
Loblolly pine
Mesquite
Netleaf hackberry
Norway spruce
Oak
Osage-orange
Pitch pine
Populus deltoides
Cercis canadensis
Pi nus strobus
Eucalyptus spp.
Alnus glutinosa
Pinus banksiana
Larix spp.
Pi nus taeda
Prosopis spp.
Celtis reticulata
Picea abies
Quercus spp.
Maclura pomifera
Pinus riqida
Northeast, Midwest
East, Midwest
Northeast, Midwest
Southwest
East, Midwest
Northeast, Midwest
East
East, Midwest
Southwest
Southwest
Northeast, Midwest
East, Midwest
Northeast, Midwest
Northeast, Midwest
Fast growing in pure stand
on spoils with pH 4.0-8.0.
Good survival on moderately
acid spoil in Illinois;
nitrogen fixer.
Tolerant to extreme acid con-
ditions at some sites.
Drought-tolerant; adapted to
dry regions.
Good for use in erosion con-
trol; tolerant of wide range
of soil pH and of high
salinity; nitrogen fixer.
Superior growth on extremely
acid sites.
Acid-tolerant; requires moist
soil with good drainage; some
species are shallow-rooting.
Superior growth on some acid-
waste embankments.
Drought- and acid-tolerant.
Deep-rooting tree; very tol-
erant of drought and alkaline
soil.
Survives well on waste banks;
slow early growth.
Average to good survival on
moderately acid spoil.
Grows well over a wide soil
pH range; good growth on
moist strip mine spoil.
Superior growth on extremely
acid soil; survives on shal-
low, dry, low-fertility
soils.
(continued)
-------
Tab! e
Common name
Trees (contd.)
Red pine
Scotch pine
Shortleaf pine
Siberian elm
Silver maple
Sitka spruce
t—•
00
Speckled alder
Sweetgum
Sycamore
Table mountain pine
Virginia pine
Scientific name
Pi nus resincsa
Pinus sylvestris
Pinus echinata
LUntus purnil a
Acer saccharinum
Picea sitchensis
Alnus rugosa
Liquidambar styraci f 1 ua
Platanus occidental is
Pi nus punqens
Pi nus vi rqi ni ana
(Continued)
Region of use
in United States
Comments
Northeast, Midwest
Northeast Midwest
Northeast, Midwest
Midwest, West
Northeast, Midwest
Northeast
East, Midwest
East, Midwest
East, Midwest
Northeast
Northeast, Midwest
Tolerant of low fertility and
dry soils; good growth on
acid spoils.
Hardy species on dry and
infertile sites.
Good growth and survival on
acid sites.
Recommended for dry climates;
adapted for alkaline and
saline conditions.
Survival only fair on acid
embankments.
Occasionally used on acid
embankments; extremely tol-
erant of alkaline and saline
conditions; high boron
tolerance.
Fast-growing; tolerant of a
wide range of soil pH, and
of high salinity; nitrogen
fixer; needs wet site for
seeding.
In preliminary tests, appears
to do better on neutral to
alkaline soils than on acid
soi 1.
Adaptable to a wide range of
soil pH; salt-tolerant.
Slow growth; fair survival on
higher acid shale.
Attains excellent height
among conifers on some coal-
waste embankments.
-------
Table C.l. (Concluded)
Species'3 Region of use
Common name Scientific name origin in United States Comments
Trees (contd.)
White spruce Picea qlauca N Northeast, Midwest Good survival on acidic
anthracite spoil.
Willow Salix spp. N East, Midwest Adaptable to a wide range of
soil pH; S. interior and
and S. nigra are volunteers
on aTkaline fly ash pits.
aData from Coalgate et al. (1973), D'Appalonia Consulting Engineers (1975), Gonsoulin (1975), Donovan et al. (1976), GAI
.Consultants (1979), and U.S. Soil Conservation Service (personal communication).
N = species native to United States; I = species introduced to United States (exotic); N/I = genus includes both native and
introduced species.
-------
REFERENCES
Coalgate, J.L., D.J. Akers, and R.W. Frum. 1973. Gob Pile Stabilization,
Reclamation, and Utilization. Report No. 75, Interim Report No. 1.
Prepared for U.S. Department of the Interior, Office of Coal Research and
Development, Washington, DC, by Coal Research Bureau, West Virginia
University, Morgantown. 127 pp.
D'Appalonia Consulting Engineers, Inc. 1975. Coal Refuse Disposal Facili-
ties; Engineering and Design Manual. Prepared for U.S. Department of the
Interior, Mining Enforcement and Safety Administration, Washington, DC.
1 v. (various pagings).
Donovan, R.P., R.M. Felder, and H.H. Rogers. 1976. Vegetative Stabilization
of Mineral Waste Heaps. EPA-600/2-76-087. U.S. Environmental Protection
Agency, Research Triangle Institute, Research Triangle Park, NC.
GAI Consultants, Inc. 1979. Coal Ash Disposal Manual. EPRI FP-1257. Pre-
pared for the Electric Power Research Institute, Palo Alto, CA, by GAI
Consultants, Inc., Monroeville, PA. 1 v. (various pagings).
Gonsoulin, G.J. 1975. A study of plant succession on three TVA fly ash pits
in middle Tennessee. Castanea 40:44-56.
150
-------
bibliographic data
SHEET
1. Report No.
FWS/0BS-81/05
3. Recipient's Accession No.
4. Title and Subtitle
COAL COMBUSTION WASTE MANUAL: EVALUATING IMPACTS TO FISH AND
WILDLIFE
5. Report Date
August 1981
6.
7. Author(s) i_arS F. Soholt, Robert W. Vocke, Vanessa A. Harris,
Mark .1. Knight, and Barrv Siskind
8. Performing Organization Rept.
No. ]
9. Performing Organization Name and Address
Division of Environmental Impact Studies
Argonne National Laboratory
9700 S. Cass Avenue
Argonne, IL
10. Project/Task/Work Unit No.
11. Contract/Grant No.
FWS-14-16-0009-79-997
13. Type of Report & Period
Covered
Final report
12. Sponsoring Organization Name and Address
Department of the Interior, U.
Office of Biological Services,
Route 3, Box 44
Kearneysville, WV 25430
S. Fish and Wildlife Service
Eastern Energy & Land Use Team
14.
15. Supplementary Notes
national policy,
a concomitant
wildlife resources.
16. Abstracts
Increased use of coal in the generation of electricity has become
With the anticipated accelerated use of coal as an energy source,
increase can be expected in the potential for impacts to fish and
The goal of this manual is to provide quantitative guidelines, where possible for
evaluating the potential extent of habitat .disturbance from waste constituent dispersal
Criteria are also provided for evaluating the potential for impact from trace elements
in the waste.
This manual is designed to be used in conjunction with the technical report entitled
"Handling of Combustion and Emission-Abatement Wastes from Coal-Fired Power Plants:
Implications for Fish and Wildlife Resources" (FWS/0BS-80/33).
This manual is limited to combustion and emission-abatement waste-handling systems and
impacts of wastes on fish and wildlife resources.
17. Key Words and Document Analysis. 17a. Descriptors
coals, coal constituents, fossil fuels, heating fuels, combustion, combustion products
combustion deposits, airborne wastes, wastes
17b. Identifiers/Open-Endecf Terms
vapers, exhaust gases, exhaust emissions, smoke, waste treatment, waste disposal,
fish and wildlife impacts
17c. COSATI Field/Group 43. g8Aj C> q. g1A; g7R
IB. Availability Statement
Unlimited
19. Security Class (This
Report)
UNjri ASSIF1ED
.. . Wt-lY.llll.-HM »««.
20. Security Class (This
"^JNC.I.ASSIFIEP
21. No. of Pages
xii + 151
22. Price
form NTis-aa IREV. 10-731 ENDORSED BY ANSI AND UNESCO.
151
USCOMM-DC S264-P74
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