United States Office of Water EPA

- 821

- R

- 13

- 003

Environmental Protection Washington, DC 20460 April 201 3 Agency



# Environmental Assessment for the Proposed Effluent

Limitations Guidelines and

Standards for the Steam Electric Power Generating Point Source Category

# Environmental Assessment for the Proposed Effluent Limitations Guidelines

and Standards for the Steam Electric Power Generating Point Source Category

EPA

- 821

- R

- 1 3

- 00 3

April 201 3

U.S. Environmental Protection Agency Office of Water (4303T) Engineering and Analysis Division 1200 Pennsylvania Avenue, NW Washington, DC 20460Acknowledgements and Disclaimer



### This report was prepared by the Environmental Protection Agency. Neither the United States Government nor any of its employees, contractors, subcontractors, or their employees make any warrant, expressed or implied, or assume any legal liability or responsibility for any third party ’s use of or the results of such use of any information, apparatus, product, or process discussed in this report, or represents that its use by such party would not infringe on privately owned rights.Table of Contents



### i TABLE OF CONTENTS Page

A CRONYMS



### ................................ ................................ ................................ ................................ ... vii

G LOSSARY



### ................................ ................................ ................................ ................................ ..... ix

S ECTION 

### 1 I NTRODUCTION



### ................................ ................................ ................................ .......... 1

- 1

S ECT ION 

### 2 B ACKGROUND AND 

### S COPE



### ................................ ................................ ........................ 2

- 1

S ECTION 

### 3 E NVIRONMENTAL 

### A ND 

### H UMAN 

### H EALTH 

### C ONCERNS



### ................................ .............. 3

- 1

3.1 Types of Pollutants Discharged in Steam Electric Waste Streams

........................... 3

- 3

3.1.1 Metals

................................ ................................ ................................ ........... 3

- 3

3.1.2 Nutrient s

................................ ................................ ................................ ....... 3

- 9

3.1.3 TDS

................................ ................................ ................................ ............. 3

- 10

3.2 Loadings Associated with Combustion Wastewater

................................ .............. 3

- 12

3.2.1 Annual Baseline Pollutant Loadings

................................ .......................... 3

- 12

3.2.2 Comparison of Steam Electric Loadings to Other Industries

..................... 3

- 14

3.2.3 Comparison of Steam Electric Loadings to Publicly Owned

Treatment Works

................................ ................................ ........................ 3

- 15

3.2.4 Pollutant Loadings to the Chesapeake Bay Watershed

.............................. 3

- 19

3.2.5 Pollutant Loadings to the Great Lakes Watershed

................................ ..... 3

- 22

3.3 Long Environmental Recovery Times Associated with Pollutants in Steam

Electric Waste Streams

................................ ................................ ........................... 3

- 24

3.4 Discharge to Sensitive Environments

................................ ................................ ..... 3

- 26

3.4.1 Proximity to Impaired Waters

................................ ................................ .... 3

- 27

3.4.2 Proximity to Fish Consumption Advisory Waters

................................ ..... 3

- 30

3.4.3 Proximity to Threatened and Endanger ed Species Habitats

....................... 3

- 31

3.4.4 Proximity to Drinking Water Resources

................................ .................... 3

- 32

3.5 Documented Environmental Impacts

................................ ................................ ..... 3

- 33

3.5.1 Case Studies and Damage Cases Documenting Surface Water Impacts

.... 3

- 34

3.5.2 Case Studies and Damage Cases Documenting Ground Water Impacts

.... 3

- 38

3.5.3 Potent ial for Impacts to Occur in Other Locations

................................ ..... 3

- 40

S ECTION 

### 4 E XPOSURE 

### P ATHWAYS



### ................................ ................................ .............................. 4

- 1

4.1 Combustion Wastewater Discharge and Leachate Entering Surface Waters

........... 4

- 2

4.1.1 Factors Controlling Environmental Impacts in Surface Waters

................... 4

- 3

4.1.2 Assessment of the Surface Water Exposure Pathway

................................ .. 4

- 4

4.2 Leaching to Ground Water

................................ ................................ ..................... 4

- 15

4.2.1 Factors Controlling Environmental Impacts to Ground Water

.................. 4

- 15

4.2.2 Assessment of the Ground Water Exposure Pathway

................................ 4

- 20

4.3 Combustion Residuals Surface impoundments as Attractive Nuisance

................. 4

- 21

S ECTION 

### 5 C URRENT 

### I MPACTS FROM 

### S TEAM 

### E LECTRIC 

### I NDUSTRY



### ................................ ......... 5

- 1

5.1 Ecological Impacts

................................ ................................ ................................ .... 5

- 1

5.1.1 Lethal Effects of Selenium

................................ ................................ ........... 5

- 1

5.1.2 Sublethal Effects of Selenium

................................ ................................ ...... 5

- 2

5.1.3 Lethal Effects of Other Metals

................................ ................................ ..... 5

- 3Table of Contents



### TABLE OF CONTENTS (Continued) Page

ii 5.1.4 Sublethal Effects of Other Metals

................................ ................................ 5

- 6

5.2 Potential for Human Health Effects

................................ ................................ .......... 5

- 6

5.3 Quantified Environmental Impacts

................................ ................................ ........... 5

- 7

5.3.1 Water Quality Impacts

................................ ................................ .................. 5

- 8

5.3.2 Wildlife Impacts

................................ ................................ ........................... 5

- 9

5.3.3 Human Health Impacts

................................ ................................ ............... 5

- 13

S ECTION 

### 6 E NVIRONMENTAL 

### I MPROVEMENTS 

### U NDER THE 

### P ROPOSED 

### R EGULATORY 

### O PTIONS



### ................................ ................................ ................................ ........................... 6

- 1

6.1 Loading Reductions Under the Proposed Regulato ry Options

................................ . 6

- 6

6.2 Key Environmental Improvements

................................ ................................ ......... 6

- 13

6.2.1 Improvements in Water Quality Under the Preferred Options

................... 6

- 16

6.2.2 Reduced Threat to Wildlife Under the Preferred Option

........................... 6

- 16

6.2.3 Reduced Human Health Cancer Risk Under the Preferred Option

............ 6

- 17

6.2.4 Reduced Threat of Non

- Cancer Human Health Effects Under the Preferred Option

................................ ................................ ......................... 6

- 17

6. 3 Pollutant

- Specific Improvements

................................ ................................ ........... 6

- 18

6.3.1 Arsenic

................................ ................................ ................................ ........ 6

- 19

6.3.2 Mercur y

................................ ................................ ................................ ...... 6

- 22

6.3.3 Selenium

................................ ................................ ................................ ..... 6

- 25

6.3.4 Cadmium

................................ ................................ ................................ .... 6

- 30

6.3.5 Thallium

................................ ................................ ................................ ..... 6

- 33

6.4 Improvements to Sensitive Environments and Watersheds

................................ .... 6

- 36

6.4.1 Impaired Waters

................................ ................................ ......................... 6

- 36

6.4.2 Threatened and Endangered Species

................................ .......................... 6

- 39

6.4.3 Fish Advisory Waters

................................ ................................ ................. 6

- 39

6.4.4 Sensitive Watersheds: Great Lakes and Chesapeake Bay

.......................... 6

- 39

6.5 Environmental and Human Health Improvements in Downstream Surface

Water

................................ ................................ ................................ ....................... 6

- 45

6.6 Attractive Nuisances

................................ ................................ ............................... 6

- 48

6. 7 Other Secondary Improvements

................................ ................................ ............. 6

- 48

S ECTION 

### 7 C ONCLUSIONS



### ................................ ................................ ................................ ........... 7

- 1

S ECTION 

### 8 R EFERENCES



### ................................ ................................ ................................ ............. 8

- 1

A PPENDIX 

### A

— L ITERATURE 

### R EVIEW 

### M ETH ODOLOGY AND 

### R ESULTS



### A PPENDIX 

### B

— P ROXIMITY 

### A NALYSES 

### S UPPORTING 

### T ABLES



### A PPENDIX 

### C

— W ATER 

### Q UALITY 

### M ODEL 

### M ETHODOLOGY



### A PPENDIX 

### D

— W ILDLIFE 

### M ODEL 

### M ETHODOLOGY



### A PPENDIX 

### E

— H UMAN 

### H EALTH 

### M ODEL 

### M ETHODOLOGY



### A PPENDIX 

### F

— A DDITIONAL 

### M ODEL 

### R ESULTS



### A PPENDIX 

### G

— M ETHOD OLOGY FOR 

### N ON



### - M ODELED 

### O PTIONSList of Tables



### iii List of Tables Page

2

- 1 Steam Electric Waste Streams Evaluated in the EA

................................ ........................ 2

- 2

2

- 2 Number of Plants Evaluated in the EA

................................ ................................ ............ 2

- 4

3

- 1 Key Metals Found In Combustion Wastewater

................................ ............................... 3

- 4

3

- 2 Annual Baseline Pollutant Discharges from the Steam Electric Industry

..................... 3

- 13

3

- 3 Pollutant Loadings for the Final 2010 Effluent Guidelines Planning Process: Top 10 Point Source Categories

................................ ................................ ............................ 3

- 14

3

- 4 Comparison of Average Pollutant Loadings in the Evaluated Waste Streams to an Average POTW

................................ ................................ ................................ .............. 3

- 18

3

- 5 Estimated Number of POTW Equivalents for Total Pollutant Loadings from the

Evaluated Waste Streams

................................ ................................ ............................... 3

- 19

3

- 6 Comparison of Steam Electric Pollutant Loadings to Other Point Source Discharges to the Chesapeake Bay Watershed

................................ .............................. 3

- 20

3

- 7 Estimated Number of POTW Equivalents for Pollutant Loadings to the Chesapeake Bay Watershed from the Evaluated Waste Streams

................................ .. 3

- 21

3

- 8 Steam Electric Pollutant Loadings to the Great Lakes Watershed

................................ 3

- 23

3

- 9 Estimated Number of POTW Equivalents for Pollutant Loadings to the Great

Lakes from the Evaluated Waste Streams

................................ ................................ ..... 3

- 24

3

- 10 Number and Percentage of Immediate Receiving Waters Identified as a Sensitive

Environment

................................ ................................ ................................ ................... 3

- 27

3

- 11 Number and Percentage of Immediate Receiving Waters Classified as Impaired

for a Pollutant Associated with the Evaluated Waste Streams

................................ ...... 3

- 28

3

- 12 Number and Percentage of Immediate Receiving Waters Issued a Fish Consumption Advisory for a Pollutant Associated with the Evaluated Waste

Streams

................................ ................................ ................................ ........................... 3

- 30

3

- 13 Comparison of Number and Percentage of Steam Electric Power Plants Located

within 5 Miles of a Drinking Water Resource

................................ ............................... 3

- 33

3

- 14 Summary of Select Documented Surface Water Impact Case Studies

.......................... 3

- 35

4

- 1 Combustion Wastewater Environmental Pathways and Routes of Exposure

Evaluated in the EA

................................ ................................ ................................ ......... 4

- 2

4

- 2 Final Outfall Receiving Water Types for Steam Electric Power Plants Within Scope of the Loadings Analysis

................................ ................................ ....................... 4

- 3

4

- 3 Metals Considered for Analysis in the Receiving Water Model

................................ ..... 4

- 8

4

- 4 Metal Conc entrations in Leachate Under Acidic Conditions (pH of 1.0 to 6.5)

........... 4

- 17

4

- 5 Metal Concentrations in Leachate Under Neutral Conditions (pH of 6.5 to 7.5)

.......... 4

- 17

4

- 6 Metal Concentrations in Leachate Under Basic Conditions (pH of 7.5 to 14)

.............. 4

- 18List of Tables



### List of Tables ( Continued ) Page

iv 4

- 7 Range of Fly Ash and FGD Total Content and Leaching Test Results (Initial Screening Concentrations) for Trace Metals

................................ ................................ . 4

- 20

5

- 1 Summary of Studies Evaluating Lethal Effects of Metals in Combustion

Wastewater

................................ ................................ ................................ ....................... 5

- 4

5

- 2 Median Lethal Concentrations (LC 50 

### ) for Metals in Combustion Wastewater

............... 5

- 5

5

- 3 Number and Percentage of Immediate Receiving Waters with Estimated Water Concentrations that Exceed the Water Quality Criteria

................................ ................... 5

- 9

5

- 4 Comparison of Modeled Selenium Concentrations in Fish Tissue to Documented

Concentrations of Selenium in Fish Tissue Known to Cause Adverse Effects

............. 5

- 10

5

- 5 Number and Percentage of Immediate Receiving Waters That Exceed Wildlife Fish Consumption NEHC for Mink and Eagle

................................ .............................. 5

- 12

5

- 6 Number and Percentage of Immediate Receiving Waters That Exceed Wildlife Fish Consumption Hazard Quotients for Mink and Eagle by Pollutant

........................ 5

- 13

5

- 7 Number and Percentage of Immediate Receiving Waters That Exceed Human Health Evaluation Criteria (Lifetime Excess Cancer Risk) for Inorg anic Arsenic

........ 5

- 14

5

- 8 Number and Percentage of Immediate Receiving Waters That Exceed Non

Cancer Oral Reference Dose Values

................................ ................................ .............. 5

- 15

5

- 9 Number and Percentage of Immediate Receiving Waters That Exceed Non

Cancer Oral Reference Dose Values by Pollutant

................................ ......................... 5

- 16

5

- 10 Comparison of T4 Fish Tissue Concentrations to Fish Advisory Screening Values

.... 5

- 17

6

- 1 Regulatory Options Evaluated in the EA

................................ ................................ ......... 6

- 3

6

- 2 Description of Environmental Improvements from Preferred Regulatory Options

........ 6

- 4

6

- 3 Steam Electric Industry Pollutant Reductions for Metals, Nutrients, Chlorides, and TDS Under Regulatory Options

................................ ................................ ....................... 6

- 9

6

- 4 Steam Electric Industry Toxic Weig hted Equivalent Pollutant Reductions for Metals, Nutrients, Chlorides, and TDS Under Regulatory Options

.............................. 6

- 11

6

- 5 Key Environmenta l Improvements Under the Regulatory Options

............................... 6

- 14

6

- 6 Key Environmental Improvements for Arsenic Under the Regulatory Options

............ 6

- 20

6

- 7 Key Environmental Improvements for Mercury Under the Regulatory Options

.......... 6

- 23

6

- 8 Comparison of Estimated Selenium Concentrations in Fish to Documented Literature Fish Impacts

................................ ................................ ................................ .. 6

- 27

6

- 9 Key Environmental Improvements for Selenium Under the Regulatory Options

......... 6

- 2 8

6

- 10 Key Environmental Improvements for Cadmium Under the Regulatory Options

........ 6

- 31

6

- 11 Key Environmental Improvements for Thallium Under the Regulatory Options

......... 6

- 34

6

- 12 Loading Reductions to Impaired Waters by Impairment Type

................................ ..... 6

- 37List of Tables



### List of Tables ( Continued ) Page

v 6

- 13 Total Loadings Removed to the Great Lakes Watershed Under the Regulatory Options

................................ ................................ ................................ ........................... 6

- 41

6

- 14 Total Loading Reductions to the Chesapeake Bay Watershed Under the Regulatory Options

................................ ................................ ................................ ........ 6

- 43

6

- 15 Key Environmental Improvements for Downstream Waters Under the Regulatory Options

................................ ................................ ................................ ........................... 6

- 46List o f Figures



### vi List of Figures Page

3

- 1 Location of Plants that Directly Discharge Combustion Wastewater to a Surface Water Impaired due to Arsenic, Mercury, and Selenium

................................ .............. 3

- 28

3

- 2 Location of Plants t hat Directly Discharge Combustion Wastewater to a Surface Water Impaired due to Metals Other than Mercury

................................ ....................... 3

- 29

3

- 3 Location of Plants that Directly Discharge Combustion Wastewater to a Surface Water Impaired due to Nutrients

................................ ................................ .................... 3

- 29

3

- 4 Location of Plants that Directly Discharge to a Surface Water with a Fish Consumption Advisory for Cadmium, Lead, and Mercury

................................ ........... 3

- 31

4

- 1 Overview of Receiving Water Model

................................ ................................ .............. 4

- 6

4

- 2 Water Quality Model: Pollutant Fate in the Water Body

................................ .............. 4

- 10Acronyms



### vii 

## ACRONYMS

ARCS Assessment and Remediation of Contaminated Sediments

ASTM American Society for Testing a nd Materials

ATSDR Agency for Toxic Substances and Disease Registry

BAT Best Available Technology Economically Achievable

BCF Bioconcentration factor

BPT Best Practicable Control Technology Currently Available

CCR Coal combustion residuals

CFR Code of Federal Regulations

CSCL Chemical stressor concentration limit

CSF Cancer slope factor

CWA Clean Water Act

DCN Document control number

DMR Discharge monitoring report

DOE Department of Energy

EA Environmental assessment

ELGs Effluent Limitations Guidelines and Standards

EP Extraction procedure

EPA U.S. Environmental Protection Agency

FGD Flue gas desulfurization

HQ Hazard quotient

IRIS Integrated Risk Information System

LADD Lifetime average daily dose
lb/yr Pounds per year

LC50 Median lethal concentrati on

LECR Lifetime excess cancer risk

MCL Maximum contaminant level

MRL Minimal risk level

MGD Million gallons per day
mg/day Milligrams per day
mg/kg Milligrams per kilogram

mg/L Milligrams per liter

NEHC No effect hazard concentration

NOAEL No

- observed

- adverse

- effect level

NPDES National Pollutant Discharge Elimination System

NRWQC National Recommended Water Quality Criteria

NSPS New Source Performance StandardsAcronyms



### viii OSWER Office of Solid Waste and Emergency Response

POTW Publicly owned treatment works

ppm Parts per million

PSES Pretreatment Standards for Existing Sources

PSNS Pretreatment Standards for New Sources

RCRA Resource Conservation and Recovery Act

RfD Reference dose

SDWA Safe Drinking Water Act

SQuiRT Screening Quick Reference Table

TC Toxicity characteristic

TCLP Toxicity characteristic leaching procedure

TDD Technical Development Document

TDS Total dissolved solids

TMDL Total maximum daily load

TRI Toxics Release Inventory

TSS Total suspended solids

TTHM Total trihalomethanes

TWF Toxic weighti ng factor

TWPE Toxic weighted pound equivalent
μg/g Micrograms per gram
μg/L Micrograms per liter

USGS United States Geological Survey

WHO World Health Organization

WMA Wildlife Management Area

WQC Water quality criteria

WQI Water quality indexGlossary



### ix 

# GLOSSARY

Acute

– having a sudden onset or lasting a short time. An acute stimulus is severe enough to

induce a response rapidly. The word acute can be used to define either the exposure or the response to an exposure (effect). The duration of an acute aquatic toxicity test is generally four days or less and mortality is the response usually measured.

Aquifer

– a n underground formation or group of formations in rocks and soils containing enough ground water to supply wells and springs.

Benthic c ommunity

– the community of organisms dwelling at the bottom of a pond, river, lake,

or ocean.

Bioaccumulation

– gener al term describing a process by which chemicals are taken up by an organism either directly from exposure to a contaminated medium or by consumption of food containing the chemical.

Biomagnification

– result of the process of bioaccumulation and biotransfe r by which tissue concentrations of chemicals in organisms at one trophic level exceed tissue concentrations in organisms at the next lower trophic level in a food chain.

Chronic

– involving a stimulus that is lingering or continues for a long time; often signifies periods from several weeks to years, depending on the reproductive life cycle of the species. This

term c an be used to define either the exposure or the response to an exposure (effect). Chronic exposures typically induce a biological response of relatively slow progress and long duration.

Coal combustion residuals (CCR)

– means fly ash, bottom ash, boiler slag, and flue gas desulfurization (FGD) materials destined for disposal. CCRs are also known as coal combustion wastes (CCWs) and fossil fuel combustion (FFC) wastes, when destined for disposal.

C ombustion residuals

– solid wastes associated with combustion

- related power plant processes, including fly and bottom ash from coal

- , petroleum coke

- , or oil

- fired units; FGD solids; flue gas

mercury c ontrol wastes; and other wastewater treatment solids associated with combustion

wastewater.

C ombustion wastewater

– all combustion

- related wastewaters evaluated as part of the steam electric proposed effluent limitations guidelines and standards (ELGs), in cluding ash transport

water from coal

- , petroleum coke

- , or oil

- fired units; air pollution control wastewater (e.g., FGD wastewater, flue gas mercury control wastewater, carbon capture wastewater); and leachate from landfills or surface impoundments contai ning combustion residuals.

Criterion maximum concentration

– is an estimate of the highest concentration of a material in surface water to which an aquatic community can be exposed briefly without resulting in an unacceptable effect.Glossary



### x Direct discharge

– was tewater discharged directly into a waterway under a National Pollutant Discharge Elimination System (NPDES) permit through a defined conveyance or system such as outlet pipes; a point source.

Edema

– swelling caused by fluid in body tissues.

Effluent l imitation

– under Clean Water Act ( CWA ) section 502(11), any restriction, including schedules of compliance, established by a s tate or the Administrator on quantities, rates, and concentrations of chemical, physical, biological, and other constituents whic h are discharged from point sources into navigable waters, the waters of the contiguous zone, or the ocean.

Evaluated waste streams

– subset of combustion wastewaters evaluated in the environmental assessment ( EA ) and Benefits and Cost A nalysis that includ es FGD wastewater, fly ash transport water, bottom ash transport water, and leachate from landfills or surface impoundments containing combustion residuals.

Exposure

– the contact or co

- occurrence of a stressor with a receptor.

Gasification wastew ater

– t aken collectively as if from one source, wastewater from all sources associated with the gasification process or related chemical recovery processes at an integrated gasification combined cycle operation. Gasification wastewater includes, but is not limite d to, slag handling wastewater, fly ash stream, sour/grey water (which consists of condensate from gas cooling, as well as other waste streams), carbon dioxide ( CO 2 

### ) /steam stripper wastewater, air separation unit blowdown, and sulfur recovery unit blowdown

.

Ground water

– water in a saturated zone or stratum beneath the surface of land.

Hematological

– pertaining to or emanating from blood cells.

Histopathological

– pertaining to tissue changes.

Impaired waters

– a surface water is classified as a 303(d) impaired water when pollutant concentrations exceed water quality standards and the surface water can no longer meet its designated uses (e.g., drinking, recreation, and aquatic habitat).

Indirect discharge

– wa stewater discharged directly to a publicly owned sewage treatment works (POTW).

Invertebrates

– animals without a backbone or spinal column; m acroinvertebrates are invertebrates that can be seen without a microscope (macro), such as aquatic insects, worms

, clams, snails, and crustaceans.

Landfill

– a disposal facility or part of a facility where solid waste, sludges, or other process residuals are placed in or on any natural or manmade formation in the earth for disposal and which is not a storage pile, a land treatment facility, a surface impoundment, an underground injection well, a salt dome or salt bed formation, an underground mine, a cave, or a corrective action management unit.Glossary



### xi Leachate

– liquid, including any suspended or dissolved constituent in th e liquid that has percolated through or drained from waste or other materials emplaced in a landfill, or that pass through the containment structure (e.g. bottom, dikes, berms) of a surface impoundment. Leachate also includes the terms seepage, leak, and l eakage, which are generally used in reference to leachate from an impoundment.

Lentic water body

– still or slow

- moving water, such as lakes or ponds.

Lethal

– causing death by direct action.

Lotic water body

– flowing water, such as streams and rivers.

Me dian l ethal c oncentration (LC 50 

### )

– a statistically or graphically estimated concentration that is expected to be lethal to 50 percent of a group of organisms under specified conditions.

Mortality

– death rate or proportion of deaths in a population.

Partition coefficient

– the ratio of a pollutant concentration in one medium compared to another (e.g., dissolved in the water column, sorbed to suspended sediment, and sorbed to benthic sediment in a receiving water).

Piscivorous

– habitually feeds on fi sh.

Point s ource

– any discernable, confined, and discrete conveyance from which pollutants are or may be discharged. See CWA section 502(14).

Population

– an aggregate of individuals of a species within a specified location in space and

time.

Receptor

– t he ecological or human entity exposed to a stressor.

Sediment

– particulate material lying below water.

Sensitivity

– in relation to toxic substances, organisms that are more sensitive exhibit adverse (toxic) effects at lower exposure levels than organisms that are less sensitive.

Stressor

– any physical, chemical, or biological entity that can induce an adverse response.

Sublethal

– below the concentration that directly causes death. Exposure to sublethal concentrations of a substance can produce effects o n behavior, biochemical and/or physiological functions, and the structure of cells and tissues in organisms.

Surface i mpoundments

– a facility or part of a facility which is a natural topographic depression,

man

- made excavation, or diked area formed primar ily of earthen materials (although it may be

lined with man

- made materials), which is designed to hold an accumulation of liquid process wastes or process wastes containing free liquids, and which is not an injection well. Examples of surface impoundments are holding, storage, settling, and aeration pits, ponds, and lagoons. Surface impoundments are used to receive combustion residuals that have been sluiced (flushedGlossary



### xii or mi x ed with water to facilitate movement), or wastes from wet air pollution control devic es, often in addition to other solid wastes.

Surface water

– all water naturally open to the atmosphere, such as rivers, lakes, reservoirs, streams, and seas.

Teratogenic

– a ble to disturb the growth and development of an embryo or fetus.

Trophic level

– position of an organism in the food chain.

Toxic pollutants

– as identified under the CWA , 65 pollutants and classes of pollutants, of which 126 specific substances have been designated priority toxic pollutants. See Appendix A to 40

CFR 423.Section 1

— Introduction



### 1-1 

# SECTION 1 INTRODUCTION

The U.S. Environmental Protection Agency (EPA) is proposing revised effluent limitations guidelines and standards (ELGs) for the Steam Electric Power Generating Point Source Category (40 CFR 423). In support of the development of the revised ELGs , EPA conducted an environmental assessment (EA) to evaluate the environmental impact of pollutant loadings released under current (i.e., baseline) discharge practices and assess the potential environmental improvement from pollutant loading reductions under varying regulatory options.

Based on evidence in the literature, documented cases studies, and modeled receiving water pollutant concentrations, it is clear that current combustion wastewater discharge p ractices at steam electric power plants impact the water quality in receiving waters, impact the wildlife in

the surrounding environments, and pose a potential human health threat to nearby communities.

Substantial evidence exists that metals (e.g., arseni c, cadmium, mercury, selenium) from combustion wastewater discharges transfer from the aquatic environment to terrestrial food

webs , indicating a potential for broader impacts to ecological systems by altering population diversity and community dynamics in the areas surrounding steam electric power plants. Ecosystem recovery from exposure to combustion wastewater discharges can be extremely slow and even short periods of exposure (e.g., less than a year) can cause observable ecological impacts that last for years.

Steam electric power plants discharge c ombustion wastewater into water bodies used for recreation and can present a potential threat to human health. Documented fish kills in waters that receive combustion wastewater discharges have resulted in states issuing fish advisories to protect the public from exposure to fish with elevated pollutant concentrations. Leachate from surface impoundments and landfills containing combustion residuals are known to impact

off -site ground water and drinking water w ells at concentrations above maximum contaminant level (MCL) drinking water standards, posing a potential threat to human health.

The goal of the EA was to answer the following five questions regarding the evaluated

waste streams included in the analysis:

• 

### What are the environmental concerns under current (i.e., baseline) discharge practices?

• 

### What are the environmental and exposure pathways for steam electric industry discharges to impact water quality, wildlife, and human health?

• 

### What are the baseline envi ronmental impacts to water quality and wildlife ?

• 

### What are the potential impacts to human health from baseline discharges?

• 

### W hat are the improvements to water quality, wildlife, and human health under the regulatory option s?

The EA evaluated environmental concerns and potential exposures (wildlife and humans) to pollutants commonly found in combustion wastewater discharges from steam electric power plants. EPA completed both qualitative and quantitative analyses. Qualitative a nalyses includeSection 1 —Introduction



### reviewing documented site impacts in literature, case studies, and damage cases; pollutant loadings to receiving waters; discharges to sensitive environments; and the effect of pollutant exposure on ecological and human receptors. To quantify baseline impacts and improvements under the proposed Steam Electric ELGs, EPA developed models to determine pollutant concentrations in the immediate and downstream receiving waters, pollutant concentrations in fish tissue, and exposure doses to ecological and human receptors from fish consumption. EPA compared the values calculated by the models to benchmarks to determine the extent of the environmental impacts nationwide.

This report presents the methodology and results of the qualitative and quantitative analyses performed to evaluate baseline discharges from steam electric power plants an d improvements under the regulatory options. The analyses presented in this report reflect the current conditions in the industry. The results do not reflect changes in the industry that may occur as a result of future EPA rulemakings such as EPA’s Office of Solid Waste and Emergency Response (OSWER)’s Coal Combustion Residual (CCR) rule and Office of Air’s National Emission Standards for Hazardous Air Pollutants (NESHAP).

In addition to the EA, t he proposed Steam Electric ELGs are supported by a number of

reports including:

• 

### Technical Development Document for Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (TDD),

Document No. EPA 821-R-13-002. This report includes background on the propose d ELGs; applicability and summary of the proposed ELGs; industry description; wastewater characterization and identifying pollutants of concern; treatment technologies and pollution prevention techniques; and documentation of EPA’s engineering analyses to support the proposed ELGs including cost estimates, pollutant loadings, and non

- water quality impact assessment (DCN SE01964).

• 

### Benefits and Cost Analysis for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generation Point Source Category (Benefits and Cost Analysis) , Document No. EPA 821-R-13-004. This report summarizes the monetary benefits and societal costs that result from implementation of the proposed ELGs (DCN SE03172).

• 

### Regulatory Impact Analysis for Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generation Point Source Categor y , Document No. EPA 821-R-13-005. This report presents a profile of the steam electric industry, a summary of the costs and impacts associated with the regulatory options, and an assessment of the proposed ELGs’ impact on employment and small businesses (DCN SE03170).

These reports are available in the public record for this rule and on EPA’s web site at http://water.epa.gov/scitech/wastetech/guide/steam_index.cfm

.

The proposed ELGs for the Steam Electric Power Generating Point Source Category are based on data generated or obtained in accordance with EPA’s Quality Policy and Information Quality Guidelines. EPA’s quality assurance (QA) and quality control (QC) activities for this

1-2Section 1

— Introduction



### 1-3 rulemaking include the development, approval and implementation of Quality Assurance Project Plans for the use of environmental data generated or collected from all sampling and analyses, existing databases and literature searches, and for the development of any models which used environmental data. Unless otherwise stated within this document, the data used and associated data analyses were evaluated as described in these quality assurance documents to ensure they are of known and documented quality, meet EPA's requirements for objectivity, integrity and utility, and are a ppropriate for the intended use.Section 2

— Background and Scope



### 2-1 

# SECTION 2 BACKGROUND AND SCOPE

The proposed Steam E lectric effluent limitations guidelines and standards (ELGs) apply

to establishments primarily engaged in generating electricity for distribution and/or sale, which results primarily from a process utilizing fos sil -type fuels (coal, petroleum coke, oil, gas) or nuclear fuel in conjunction with a thermal cycle using the steam water system as the thermodynamic medium (40 CFR 423.10). The U.S. Environmental Protection Agency (EPA) is proposing to revise or establish Best Available Technology Economically Achievable ( BAT) limitations, New Source Performance Standards ( NSPS), Pretreatment Standards for Existing

Sources (PSES), and Pretreatment Standards for New Sources (PSNS) that may apply to discharges of seven wastewater streams: flue gas desulfurization (FGD) wastewater, fly ash transport water, bottom ash transport water, leachate from landfills and surface impoundments containing coal combustion residuals (CCR), wastewater from flue gas mercury control (FGMC)

syst ems, wastewater from gasification systems, and nonchemical metal cleaning wastes. See the Technical Development Document for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (TDD) (DCN

SE 01964) for more information on the rule applicability and definitions, waste streams and pollutants of concern, treatment technologies, baseline and option pollutant loadings, costs of implementing treatment technologies, and option selection.

In this report, EPA uses the term

“combustion wastewater ” as all combustion

related wastewaters evaluated as part of the proposed Steam Electric ELGs. For the the environmental assessment (EA) , EPA evaluated only a subset of the waste streams (see Table 2-1 below). 1 

### “C ombustion

residuals” are the solid wastes associated with combustion-related power plant processes, including fly and bottom ash; FGD solids; flue gas mercury control wastes ; and other

wastewater treatment solids associated with

combustion wastewater. The term “coal combustion residuals (CCR)” means solid

wastes associated with the CCR rule that includes fly ash, bottom ash, boiler slag, and

FGD materials destined for solid w aste disposal.

1 EPA evaluated technology options associated with FGMC wastewater, gasification wastewater, and nonchemical metal cleaning wastes as part of the regulatory options. However, no plants currently discharge FGMC wastewater; all existing gasification plants are operating the technology used as the basis for the regulatory option; and the proposed limitations and standards for nonchemical metal cleaning wastes are equal to current Best Practicable Control Technology Currently Available (BPT) limitations for existing direct dischargers. Therefore, EPA estimated zero compliance costs and zero pollutant reductions associated with these waste streams and did not include these

three waste streams in the EA. Man y steam electric power plants use large surface impoundments to store and treat wastewater s. These impoundments are hydrologically connected to surface and ground water.Section 2

— Background and Scope



### 2-2 Steam electric power plants generate solid residuals from fuel combustion and from emission control technologies. These solid residuals include fly ash, bottom ash, and FGD solids.

Plants remove these solid materials through both wet and dr y handling methods. Dry handling typically involves transferring the solids to a storage silo or outdoor storage pile, either to bedisposed of in a landfill or, depending on the particular residual, used to create beneficial byproducts such as wallboard or cement. However, many plants use wet handling systems, which typically transfer the wastes to a surface impoundment ( e.g. , ash pond) using large quantities of water. For example, in wet systems, bottom ash collects at the bottom of the boiler in a water

bath , and the water containing the bottom ash is then typically transported to a surface impoundment for storage and/or disposal. Fly ash may be handled similarly after it is collected from the particulate collection system. The slurry stream exiting wet FGD systems, which contains 10 to 20 percent FGD solids, is typically either discharged to a surface impoundment or sent to an advanced wastewater treatment system prior to discharge to a receiving stream or reused in other plant processes. Section 4 of th e TDD describes the industry waste streams in

detail. Table 2-1 lists the specific waste streams evaluated in the EA.

Table 2-1. Steam Electric Waste Streams Evaluated in the EA

Evaluated Waste Stream Description
Fly ash transport water Water used to convey the fly ash particles removed from the flue gas via a collection

system

.

Untreated ash transport waters contain significant concentrations of total suspended solids (TSS) and metals. The effluent from ash ponds generally contains low concentrations of TSS; however, metals are still present in the wastewater, predominantly in dissolved form

. Fly ash transport water contains significant concentration of metals, including arsenic, calcium, and titanium (see Section 6 of the TDD for further details)

. Bottom ash transport water Water used to convey the bottom ash particles collected at the bottom of the boiler.

As noted above, u ntreated ash transport waters contain significant concentrations of

TSS and metals

. FGD wastewater Wastewater generated from a wet FGD scrubber system

. Wet FGD systems are used to control sulfur dioxide (SO 2 ) emissions from the flue gas generated in the plant’s

boiler.

The pollutant concentrations in FGD wastewater vary from plant to plant depending on the coal type, the sorbent used, the materials of construction in the FGD system, the FGD system operation, the level of recycle within the absorber, and the air pollution control systems operated upstream of the FGD system

. FGD wastewater contains significant concentrations of chloride s
, total dissolved solids ( TDS )

, nutrients, and metals, including bioaccumul ative pollutants such as arsenic, mercury,

and selenium (see Section 6 of the TDD for further details)

. Landfill and surface impoundment leachate Liquid that has percolated through or drains from a landfill or a pond , where the steam electric power plant disposes of or stores a variety of wastes from the combustion process.

L eachate contains high concentration of metals, such as boron, calcium, chloride, and sodium, similar to FGD and ash wastewaters. The metals pre sent in the leachate are generally at lower concentrations than those seen in FGD wastewater and ash

transport water (see Section 6 of the TDD for further details)

.Section 2

— Background and Scope



### 2-3 Surface impoundments act as a physical treatment process to remove particulate

material fr om wastewater through gravitational settling. The wastewater in surface impoundments can include one specific type of

wastewater (e.g., fly ash transport water) or a

combination of wastewaters (e.g., fly ash transport water and FGD wastewater). Additionally, plants may transfer wastewater

streams from other operations into their on- site impoundments (e.g., cooling tower blowdown or metals cleaning wastes). The waste streams sent to surface impoundments can also include coal pile runoff. Although coal pile runoff is not the result of a combustion process, it can contain many of the pollutants present in coal

fired power plant combustion wastewater. Leachate or seepage may occur from surface impoundments or landfills containing combustion residu als. Regardless of whether they use surface impoundments or an advanced treatment system, plants typically discharge combustion wastewater into the natural environment where numerous studies have raised concern regarding the toxicity of these waste streams [ERG, 2013f; NRC, 2006; Rowe et al., 2002; U.S. EPA, 2007b]. Previous regulations at 40 CFR 423 control pH and polychlorinated biphenyls (PCBs) discharge from all waste streams and TSS and oil and grease from ash transport waters and other

“low -volume wastes” that include air pollution control wastewater (see Section 1 of the TDD).

Section 6 of the TDD discuss es wastewater characterization and selection of pollutants of

concern.

Based on 2009 data from the Department of Energy and additional data EPA obtained

from the 2010 Questionnaire for the Steam Electric Power Generating Effluent Guidelines (the

Steam Elec tric Survey ), EPA estimates that 1,079 steam electric power plants are subject to the proposed regulation. However, EPA estimates that only 386 plants generate one or more of the waste streams that are included in the proposed revisions to the ELGs. Additionally, because some of these plants do not discharge any of the waste streams

, already comply with the proposed revisions, or have plans to comply with the proposed revisions prior to January 1, 2014,

EPA determined that only a subset (290 plants) are likely to achieve pollutant reductions as a result of the proposed ELGs, depending on their operations. In the EA, EPA evaluated the current impact and potential improvement to the environment and human health from a further subset of 281 plants that discharge directly to surface waters and that EPA projects will achieve reduced loadings as a result of the regulatory options evaluated. Table 2-2 presents the number of plan ts by discharge type (direct or indirect) included in the cost and loadings analysis presented

in Section 10 of the TDD. Surface impoundments accumulate high concentrations of toxic pollutants from fly ash transport waters, bottom ash transport waters and FGD wastewater.Section 2

— Background and Scope



### 2-4 Table 2-2 . Number of Plants Evaluated in the EA

Plant Description Number of

Plants
Number of Plants in Scope of Proposed ELGs
Plants that fall under the applicability of the proposed ELGs (40 CFR 423) 1,079
Cost and Loadings Analysis

Plants for which EPA calculated loading s in the cost and loadings analyses
(see Section 10 of the TDD) 290

Plants that discharge only to surface waters (direct discharger) 277
Plants that discharge only to Publicly Owned Treatment Works (POTWs) (indirect discharger) 9
Plants that discharge to surface waters and to a POTW (direct and indirect discharger) 4

Environmental Assessment
Plants evaluated in Steam Electric ELGs EA (includes all direct discharge rs ) 281



### EPA conducted an extensive literature search to collect documented cases of

envir onmental impacts that are relevant to steam electric power plant discharges. 2 

### Based on environmental impacts identified during the literature search, EPA identified several environmental concerns and routes of exposure to address in the EA. The EA comprised both qualitative and quantitative assessme nts of the current impact that steam electric power plants are having on the environment and the potential to impact human health. The EA also provided an

assessment of the potential improvements projected to occur following implementation of the regulatory options considered by EPA. Qualitative analyses included reviewing documented site impacts in literature, case studies, and damage cases; pollutant loadings to receiving waters; discharges to sensitive environments; and the effect of pollutant exposure o n ecological and human receptors. To quantify baseline impacts and improvements under the proposed Steam Electric ELGs, EPA developed computer models to determine pollutant concentrations in the immediate and downstream receiving waters, pollutant concentrations in fish tissue, and exposure doses to ecological and human receptors from fish consumption. EPA compared the values calculated by the models to benchmarks to determine the extent of the environmental impacts nationwide.

EPA used the results from qua ntitative and qualitative assessments combined with the literature review to evaluate and describe the environmental impacts caused by the discharge of the evaluated waste streams. EPA organized the remainder of this report into the following five

sections :

• 

### Section 3 describes the environmental concerns associated with the evaluated waste streams, including a discussion of the pollutants of concern and documented ca se studies and damage cases showing negative impacts to surface water and ground

water;

• 

### Section 4 outlines how ecological and human receptors may be exposed to pol lutants (i.e., environmental pathways), provides a qualitative description of factors that control environmental impacts for each pathway, and gives an overview of the

2 EPA discusses the results of the literature review throughout this report. Appendix A provides details on the literature search methodology and summary of results.Section 2

— Background and Scope



### 2-5 methodology used to quantitatively evaluate the environmental and human health impacts;

• 

### Section 5 presents the environmental and human health impacts based on qualitative review and quantitative assessments (modeling of plant- specific discharges) of

c urrent (baseline) discharges ;

• 

### Section 6 presents the improvements to the environment and human health estimated from the implementation of the regulatory options; and

• 

### Section 7 presents EPA’s conclusions on the environmental and human health improvements estimated under the proposed ELGs.Section 3

— Environmental And Human Health Concerns



### 3-1 

# SECTION 3 ENVIRONMENTAL AND HU MAN HEALTH CONCERNS

Current scientific literature indicates that combustion wastewater is not a benign waste [NRC, 2006 ; Rowe et al., 2002]. Many of the common pollutants (e.g., selenium, mercury, and arsenic) found in the waste streams evaluated as part of the environmental assessment (i.e., fly ash and bottom ash transport wate r, flue gas desulfurization (FGD) wastewater, and leachate) present an increased ecological threat due to their tendency to persist in the environment and bioaccumulate in organisms. This often results in slow ecological recovery times following

exposure. The toxic impacts of combustion wastewater contamination to surface waters have been well documented in studies of over 30 aquatic ecosystems receiving discharges from steam electric power plants. 3



### The U.S. Environmental Protection Agency (EPA) did not find documented cases of human health impacts from coal combustion wastewaters. However, documented exceedances of drinking water maximum contaminant levels ( MCLs) downstream of steam electric power plants and the issuance of fish advisories in receiving wat ers
, indicate a n ongoing human health concern. In a number of damage cases, EPA found that ground water contamination from combustion wastewater resulted in pollutant concentrations exceeding MCLs, indicating a potential human health impact [NRC, 2006 ; U.S . EPA , 2007b ]. There were three damage cases

that documented instances where leachate contamination impacted private drinking water wells. In other damage cases, EPA documented locations where selenium in combustion wastewater discharges resulted in fish consumption advisories being issued for surface waters (for selenium ). For example, a series of major fish kills occurred i n 1978 and 1979 at Martin Lake (Texas) due

to the elevated concentrations of selenium in the water and fish tissue. Studies conducted throughout the 1980s documented histopathological and reproductive damage in the fish populations inhabiting the lake. In addition, the studies determined that the overall health of the aquatic populations near the discharge s ite remained adversely affected by the selenium pollution, despite the reduction in the annual discharge of selenium. In 1992, a fish consumption advisory was issued for the lake [ATSDR, 1998c].

Documented ecological impacts include acute effects (e.g., fi sh kills) and chronic effects (e.g., malformations, and metabolic, hormonal, and behavioral disorders) upon biota within the receiving water and surrounding environment. Numerous case studies and damage cases document the toxic impacts of combustion wastew ater contamination to ground water and potential to impact off

- site sources as a result of leaching from landfills and surface impoundments (often unlined) [AECOM, 2009; ASU, 2009; DRBC, 2006; EIP, 2010a and 2010b; ERG, 2012b; Gazette, 2011; MACo, 2007; MDNRE, 2010; U.S. EPA, 2007b and 2010e]. A number of studies performed in the 1970s and 1980s outlined toxic impacts on ground water from fly ash, bottom ash, and other combustion wastewater; toxic impacts include deleterious increases in conductivity, total suspended solids (TSS), total dissolved solids (TDS), pH, sodium,

and metals – aluminum, arsenic, cadmium, iron, mercury, s elenium , and zinc [Cherry, 2000].

3 Sources include ATSDR, 1998a, 1998b and 1998c; Charlotte Observer, 2010; DOE, 1992; EIP, 2010a and 2010b; Roe et al., 2005; Sorensen et al., 1983; Sorensen, 1988; Specht et al., 1984; U.S. EPA, 2007b; and Vengosh et al.,

2009.Section 3

— Environmental And Human Health Concerns



### 3-2 While these sites are often assumed to be anomalies, an increasing amount of evidence indicates that the characteristics contributing to the documented impact (e.g., magnitude of the pollutant loadings, type of pollutant present in the waste, plant operations, and wastewater handling techniques) are common among steam electric power plant discharge locations [Cherry, 2000; NRC, 2006; Rowe et al., 2002].

EPA identified a recent study that evaluated the environmental and ecological impacts that steam electric industry discharges have on receiving waters in North Carolina [Ruhl, 2012].

The study evaluated ten surface water sites that receive combustion wastewater discharges and determined that these sites contain high levels of contaminants as a result of these discharges

. From the data collected between 2010 and 2012, contaminant levels at multiple sites exceeded drinking water standards and/or National Recommended Water Quality Criteria ( NRWQC ) . For example, arsenic concentration s at two outfalls were as high as 45 micrograms per liter (μg/L) and 92 μg/L, respectively. The drinking water MCL for arsenic is 10 μg/L. When compared to the upstream pollutant concentrations at the ten North Carolina sites, data showed elevated levels of contaminants such as boron, chromium, selenium, bromine, arsenic, and thallium. Elevated pollutant concentrations were also found in lake sediments (arsenic and selenium) and pore water near lake bottoms (including manganese, arsenic, nickel , and bromine). Even at low concentrations, pollutants can cause negative impacts in the receiving water. Negative impacts to

fish included deformities at one lake due to elevated selenium concentrations.

This section details the following environmental concerns associ ated with combustion

wastewater discharges from steam electric power plants :

• 

### Changes in surface water quality and sediment contamination levels;

• 

### Changes in ground water quality and potential contamination of private drinking

water wells ;

• 

### B ioaccumulation of contaminants in fish and aquatic life, fish eaten by p iscivorous

wildlife (i.e., fish- eating wildlife) , and fish eaten by humans ; and

• 

### T oxic effects on fish and aquatic life

.

The pollutants commonly discharged in the evaluated waste streams cause environm ental harm by contaminating surface water and ground water (e.g., selenium concentrations from steam electric power plants have resulted in fish kills). Long residence times for pollutants following release into the environment result in pollutant bioaccumulation and binding with the sediment. There is documented evidence of slow ecological recovery as a result of these pollutant discharges. Steam electric power plants also discharge to sensitive environments (e.g., impaired waters , waters under a fish consumption advisory , Great Lakes, valuable estuaries, and drinking water sources ). Some impacts m ight not be realized for years due to the persistent and bioaccumulative nature of the pollutants released. Based on the pollutant loadings calculated for

the pro posed Steam Electric ELGs, t he total amount of toxic pollutants currently being released in wastewater discharges from steam electric power plants is significant and raises concerns regarding the long-term impacts to aquatic organisms, wildlife, and humans that are exposed to these pollutants. For details on the pollutant loadings analysis, see Section 10 of the Technical Development Document for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (TDD) (DCN SE01964 ).Section 3

— Environmental And Human Health Concerns



### 3-3 3.1 T YPES OF 

### P OLLUTANTS 

### D ISCHARGED IN 

### S TEAM 

### E LECTRIC 

### W ASTE 

### S TREAMS



### This section provides an overview of the pollutants in combustion wastewater discharges that are frequently cited as affecting local wildlife or have the potentia l to pose a threat to human health. A number of variables can affect the composition of combustion wastewater , including

fuel composition, type of combustion process, air pollution control technologies implemented, and management techniques used to dispose of combustion wastewater [ Carlson and Adriano, 1993] . In addition , commingli ng combustion wastewater with other waste streams from the plant in surface impoundment s can result in a chemically complex effluent that is released to the environment [ Rowe et a l., 2002]. To identify pollutants of concern for the proposed ELGs, EPA used the following sources of wastewater characterization data in hierarchic order: EPA’s field sampling program; industry -supplied data including data provided in questionnaire respon ses; and various literature sources (see Section 6 of the TDD and the preamble to the proposed ELGs). Pollutants such as metals, nutrients, and TDS (including chloride and bromides) are the common pollutants found in combustion wastewater that have been as sociated with documented environmental impacts or could have the potential to cause environmental impacts based on the

load ings and concentrations present in the evaluated waste streams

.

3.1.1 Metals

Studies commonly cite m etals as the primary cause of ecologica l damage following exposure to combustion wastewater [Rowe et al., 1996; Lemly, 1997; Hopkins et al., 2000; Rowe et al., 2002]. The concentrations of metals present in combustion wastewater tend to vary based on the type of fuel (e.g., coal) used by the plant. An important consideration in evaluating metals is their bioavailability –the proportion of total metals that can be incorporated into organisms. A metal’s bioavailability is affected b y the characteristics of both the metal and surrounding environment (e.g., temperature, pH, salinity, oxidation-reduction (redox) potential, total organic content, suspended particulate content, and water velocity). Environmental conditions influence the tendency of a dissolved metal to remain in solution or precipitate out of solution, sorb to either organic or inorganic suspended matter in the water column, or sorb to the mixture of materials (e.g., clays and humic matter) found in sediments [U.S. EPA , 2007a]. Metals that precipitate out of solution can become concentrated in the sediments of a water body. While organisms can bioaccumulate metals by either consuming metal

- enriched sediments and suspended particles or by filtering ambient water containing dissolved metals, organisms concentrate free metal ions from solution (i.e., dissolved metals) more efficiently than by consuming metal- enriched particulate matter [USGS, 1995]. Table 3-1 lists some of the common

metals found in combustion wastewater that have been associated with documented health and environmental impacts or could potential ly cause health and environmental impacts based on the

load ings and concentrations present in the wastewater. Table 3-1 is intended to highlight the

metals identified as pollutants of concern in combustion wastewater associated w ith health and environmental impacts and does not include all metals that may cause adverse impacts. Metals in steam electric industry wastewater are present in both soluble (i.e., dissolved) and particulate (i.e., suspended) form . Based on EPA sampling data collected in support of the proposed Steam Electric ELGs, some metals such as arsenic are present mostly in particulate form while other pollutants such as selenium and boron are present mostly in soluble form. The remainder of the section provides additional details on several key metals included in the EA.Section 3

— Environmental And Human Health Concerns



### 3-4 Table 3-1. Key Metal s Found In Combustion Wastewater

Pollutant Examples of Potential Health and Environmental Concerns

Aluminum Aluminum contamination can lead to the inability of fish to maintain the balance of their fluids and is associated with damage to amphibian eggs and larvae, mostly in areas under acid stress. Human exposure to high concentrations has been linked to Alzheim er’s Disease.

Arsenic a Arsenic contamination causes poisoning of the liver

, developmental abnormalities , behavioral impairments, metabolic failure, reduced growth, and appetite loss in fish and is associated with an

increased risk of cancer in humans in the liver and bladder.

Boron Leachate has caused ground water to exceed state drinking water standards for boron . Human exposure to high concentrations can cause nausea, vomiting, and diarrh ea. Pollutant can be toxic to vegetation.

Cadmium Cadmium contamination can lead to developmental impairments in wildlife and skeletal malformations in fish. Human exposure to high concentrations can lead to kidney, liver, and lung

failure.

Chromium b Studies have found elevated chromium levels in ground water contaminated by leachate. Chromium is not known to bioaccumulate in fish; however, high concentrations of chromium can lead to gill damage, reduced growth, and altered metabolism in fish. Human ex posure to high concentrations can cause gastrointestinal bleeding and lung problems.
Copper Copper contamination can lead to reproductive failure, gill damage, and reduced sense of smell in

fish

. Human exposure to high concentrations can cause nausea, vomiting, diarrhea, and liver and kidney damage.

Iron Leachate from combustion residuals stored in surface impoundment s has caused elevated iron concentrations in nearby surface water. Iron contamin ation can lead to growth reduction, greater susceptibility to injury and disease, and decreased egg hatchability in fish. Human exposure to high concentrations can cause metabolic changes and damage to the pancreas, liver, spleen, and heart.

Lead Leachat e has caused ground water to exceed state drinking water standards for lead

. Lead contamination can result in delayed embryonic development, suppressed reproduction, and inhibited growth in fish. Human exposure to high concentrations in drinking water can cause serious damage to the brain, kidneys, nervous system, and red blood cells.
Manganese Leachate has caused elevated manganese concentrations in nearby ground water and surface water. Manganese primarily accumulates in organisms lower in the food chain such as phytoplankton, algae, mollusks, and some fish. Although high levels can be toxic to humans, manganese is not generally considered toxic when ingested. The most common impacts due to human exposure to high concentrations involve the nervous system.
Mercury c The pollutant can convert into methylmercury, increasing the potential for bioaccumulation. Methylmercury contamination can lead to reduced growth and reproductive success in fish and

invertebrates. Human exposure at levels above the MCL for re latively short periods can result in kidney and brain damage. Fetuses, infants, and children are particularly susceptible to impaired neurological development from methylmercury exposure.

Nickel At low concentrations, nickel can inhibit the growth of mic roorganisms and algae. Nickel toxicity

in fish and aquatic invertebrates varies among species, and can damage the lungs, immune system, liver, and kidneys. Human exposure to high concentrations can cause gastrointestinal and kidney damage.

Selenium d Selenium readily bioaccumulates. Elevated concentrations have caused fish kills and numerous sublethal effects (e.g., organ damage, decreased growth rates, reproductive failure) to aquatic and terrestrial organisms. In humans, s hort

- term exposure at levels above the MCL can cause hair and fingernail changes, damage to the peripheral nervous system, and fatigue and irritability. Long

- term exposure can damage the kidney, liver, and nervous and circulatory systems.

Thallium In humans, short

- term exposure to thallium can lead to neurological symptoms, alopecia, gastrointestinal effects, and reproductive and developmental damage. Long

- term exposures at levels above the MCL lead to changes in blood chemistry, and damage to liver, kidney, intestinal and

testicula r tissues, and hair loss.Section 3

— Environmental And Human Health Concerns



### 3-5 Table 3-1. Key Metal s Found In Combustion Wastewater

Pollutant Examples of Potential Health and Environmental Concerns

Vanadium Vanadium contamination can lead to increased blood pressure and neurological effects in animals. There are very few reported cases of oral exposure to vanadium in humans; however, a few reported incidences documented diarrhea and stomach cramps. It also has been linked to the development of some neurological disorders and cardiovascular diseases.

Zinc Zinc contamination leads to behavioral changes, reduced oxygen supply, and reproductive impairment in fish. In humans, s hort

- term exposure can cause nausea, vomiting, and stomach cramps. Long

- term exposure can cause anemia.

a – Arsenic exists in two primary forms: arsenic III and arsenic V.

b

– Chromium exists in two primary forms: chromium III and chromium VI.

c – The EA evaluated two forms of mercury: total mercury and methylmercury.

d

– Selenium exists in two primary forms: selenium VI (selenate) and selenium IV (selenite).



### Selenium

Selenium is the most frequently cited pollutant associat ed with documented environmental impacts to ecological receptors following exposure to combustion wastewater [NRC, 2006] . The toxic potential of selenium is related to its chemical form and solubility. The predominant chemical forms of selenium in aquatic systems that receive combustion

wastewater discha rges are selenite and selenate [Besser et al., 1996] . Availability of selenium is controlled by dissolved oxygen levels, hardness, pH, salinity, temperature, and the other chemical constituents present [ NPS, 1997]. In alkaline conditions, selenite (Se(IV)) will oxidize in the presence of oxygen to become selenate (Se(VI)) ; selenate is both stable and soluble and is the commonly found form of the chemical in alkaline soils and waters. In acidic conditions,

sel enite is insoluble due to its tendency to bind to iron and aluminum oxides [ WHO, 1987 ]. Because combustion wastewater may be

alkaline or acidic , the form of selenium present in a particular waste stream d epend s on the type
of fuel used, the fuel composition, and the amount of metal oxides present in the

wastewater.

The extent to which selenium is found in ecological receptors is affected by bioaccumulation, biomagnification, and maternal transfer. Bioaccumulation occurs when an organism absorbs a toxic substance through food and exposure to the environment at a faster rate

than the body can remove the substance. The bioaccumulation of selenium is of particular concern due to the potential for it to impact higher trophic levels through biomagnification [Coughlan and Velte, 1989] and offspring through maternal transfer [Hopkins et al., 2006; Nagle Metal Impacts to Ecological Receptors

• Due to bioaccumulation, seleniumrelated environmental impacts can linger for years even after exposure to

combustion wastewater has ceased.

• Fish and invertebrates exposed to

combustion wastewater have exhibited elevated mercury levels in their tissues and developed sublethal effects such as

redu ced growth and reproductive

success.

• Elevated arsenic tissue concentrations are associated with several biological impacts such as liver tissue death, developmental abnormalities, and reduced growth.Section 3

— Environmental And Human Health Concerns



### 3-6 et al., 2001]. A laboratory study demonstrated that diet can be an important source of trace element exposure in aquatic snakes and potentially other amphibians [Hopkins et al., 2002]. Hopkins reported that the snakes accumulated significant concentrations of the trace elements,

with selenium accumulation being the most notable. This study also revealed that amphibian prey species are able to migrate considerable distances and can therefore be exposed to toxic levels of selenium, even if they do not inhabit a contaminated site. Because of bioaccumulation and biomagnification, selenium- related environmental impacts can linger for years even after exposure to combustion wastewater has ceased [ Rowe et al., 2002].

The primary selenium

- related impacts observed by scientists include lethal effects such as fish kills; sublethal effects such as histopathological changes and damage to reproductive and developmental success; and the impacts of these effects on aquatic populations and communities. In a 1991 study, Sorensen found that dissolved selenium levels as low as 3 to 8 μg/L in aquatic environments can be life-threatening to fish [NPS, 1997]. Aquatic organisms exposed to

comb ustion wastewater have exhibited elevated selenium concentration in organs such as their kidneys, liver, and gonads, resulting in abnormalities that hinder growth and survival [Rowe et al., 2002].

In addition to ecological impacts, EPA has documented numer ous damage cases where

selenium in combustion wastewater discharges resulted in fish consumption advisories being

issued for surface waters and selenium MCLs being exceeded in ground water, suggesting that

selenium concentrations in combustion wastewater have the potential to impact human health [NRC, 2006; U.S. EPA, 2007b]. Short- term exposure at levels above the MCL can cause hair and fingernail changes , damage to the peripheral nervous system, and fatigue and irritability in humans. Long

- term exposure ca n damage the kidney, liver, and nervous and circulatory systems. For more information on lethal and sublethal effects of selenium, refer to the selenium discussion

in Section 5.1

.

Mercury

M ercury is a volatile metal and highly toxic compound that represents an environmental

and human health threat even in small concentrations. One of the primary environmental concerns regarding mercury concentrations in

combustion wastewater is the potential for methylmercury to form in combustion residuals surface impoundments and constructed wetlands prior to discharge and in receiving waters following discharge . Methylmercury is an organic form of mercury that readily bioaccumulates in fish and other organ isms and is associated with high rates of reproductive failure [ WHO, 1976]. Bacteria found in anaerobic conditions, such as those that may be present in sediments found on

the bottom of combustion residuals surface impoundments or in river sediments, conve rt Metal Impacts to Human Receptors

• Pregnant women exposed to mercury can pass the contaminant to their developing fetus, leading to possible

mental retardation an d damage to other parts of the nervous system.

• Inorganic arsenic is a carcin ogen (i.e., causes cancer). Cadmium is a suspected carcinogen.



### • Human exposure to high concentrations of lead in drinking water can cause serious damage to the brain, kidneys, nervous system, and red blood cells, especially in

children.Section 3

— Environmental And Human Health Concerns



### 3-7 mercury to methylmercury through a process called methylation [WHO, 1976]. Microbial methylation rates increase in acidic and anoxic environments with high concentrations of organic

matter. S ublethal effects from mercury exposure include reduced growth and reproductive

success, metabolic changes , and abnormalities of the liver and kidneys. Human exposure at levels above the MCL for relatively short periods of time can result in kidney and brain damage. Pregnant women who are exposed to mercury can pass the contaminant to their developing fetus, leading to possible mental retardation and damage to other parts of the nervous system [A TS DR, 1999]. Studies have documented fish and invertebrates exposed to mercury from combustion

wastewater exhibiting elevated levels of mercury in their tissues and developing sublethal effects such as reduced g rowth and reproductive success [Rowe et al., 2002].

Arsenic

Arsenic, like selenium, is of concern because it is soluble in near-neutral pH and in alkaline conditions, whi ch are commonly associated with combustion wastewater

. Therefore, arsenic is highly mobile and is frequently observed at elevated concentrations at sites located downstream from combustion residuals surface impoundments [NRC, 2006] . Inorganic arsenic, a carcinogen (i.e., causes cancer) , is found in natural and drinking waters mainly as trivalent arsenite (As(III)) or pentavalent arsenate (As(V)) [WHO, 2001]. Both the a rsenite and arsenate forms are highly soluble in water.

Arsenic is also of concern due to its tendency to bioaccumulate in aquatic communities and potentially impact higher-trophic-level organisms in the area. For example, studies have documented water snakes, which feed on fish and amphibians, with arsenic tissue concentrations higher than the ir pre y [ Rowe et al., 2002] . Elevated arsenic tissue concentrations are associated with several biological impacts such as liver tissue death, developmental abnormalities, behavioral impairments, metabolic failure, reduced growth, and appetite loss [ NRC, 2006; Rowe et al., 2002, U.S. EPA 2011f].

Human exposure to arsenic will likely occur through ingesting contaminated drinking

water [WHO, 2001]. Exposure can also occur by consuming contaminated fish ; h owever, several

studies have shown that most arsenic in fish is organic and not harmful to humans . Inorganic arsenic, which can cause cancer in humans, typically makes up less than 4 percent of the total

arsenic that accumulates in fish [U.S. EPA, 1997b].

EPA has documented several damage cases where arsenic levels exceeded drinking water standards in ground water near combustion residuals surface impoundment s [U.S. EPA, 2007b].

Arsenic contamination of ground water at the levels documented represents a pot ential human health threat, if either the aquifer is used as a drinking water source or the ground water

contaminates a downstream drinking water source.

Cadmium

The speciation and toxicity of cadmium in water depend s on the water’s salinity, hardness, temperature, and organic content [WHO, 1992]. Cadmium tends to bioaccumulate readily in mollusks, soil invertebrates, and microorganisms. Due to its chemical similarity with calcium, it can also interfere with calcium uptake in aquatic organisms, which can lead toSection 3

— Environmental And Human Health Concerns



### 3-8 sub lethal effects in fish such as skeletal malformation. Divalent cadmium (Cd(II)) is the species most commonly found in an aquatic environment, but depending on the quality of the water, cadmium can also occur as cadmium carbonate, hydroxide, sulfite, sulfate or chlorides.

Cadmium is a probable or suspected carcinogen [ATSDR, 2008a]. In humans, chronic low-level exposure to cadmium from contaminated drinking water can lead to cadmium poisoning, which is primarily associated with failure of the kidney and liver, but may also impact the lungs.

Thallium

Thallium typically exists as the monovalent or trivalent thallium ion [WHO, 1996] . It is soluble in most waters and is readily available to aquatic life. Bioconcentration factors are high

for fish and v egetation in fresh and marine waters, as well as marine invertebrates, which suggests that thallium may be a potential threat to higher order organisms in vulnerable

ecosystems [U.S. EPA, 2011a]. Studies in humans and animals indicate that thallium compounds are readily absorbed through ingestion of food and water and maternal transfer [WHO, 1996].

Thallium can accumulate in the hair and bone; however, studies often observed the highest concentrations in the endocrine glands, kidneys, liver, and intestine [WHO, 1996].

Elevated thallium concentrations can lead to neurological symptoms (e.g., weakness, sleep disorders, muscular problems), alopecia (i.e., loss of hair from the head and body), and gastrointestinal effects (e.g., diarrhea and vomiting). Long

- term exposures at levels above the MCL lead to changes in blood chemistry; damage to liver, kidney, and intestinal and testicular tissues; and hair loss. Thallium exposure can also lead to reproductive and developmental damage [U.S. EPA, 2009 a]

.

Lead

Neither metallic lead nor many of its common mineral forms are soluble in water, although it can be soluble in some acids or water with low pH; thus, lead is commonly present in precipitate form in water. Therefore, combustion wastewater may initially have high concentrations of lead, but later sampling of the wastewater can show decreased concentrations

because the lead settles out quickly. Lead will accumulate in aquatic organisms, but

bioconcentration factors can cover a wide range and depend on the spec ies. Studies have shown lead to cause delayed embryonic development and suppressed reproduction and inhibition of growth rate among fish, crab, and several other aquatic organisms [U.S. EPA, 1984]. Human exposure to high concentrations of lead in drinking water can cause serious damage to the brain, kidneys, nervous system, and red blood cells , especially in children

.

Boron

Boron is primarily found in the environment combined with oxygen in compounds called borates [ATSDR, 2010b]. Boron concentrations in No rth American waters are typically below 0.1 milligrams per liter (mg/L) [WHO, 1998], although areas with natural boron-rich deposits may have ground water levels as high as 300 mg/L [ATSDR, 2010b]. The World Health Organization (WHO) suggests that the potential of adverse effects of boron on the aquatic ecosystem is low because the no -effect concentration (1 mg/L) is much greater than levels foundSection 3

— Environmental And Human Health Concerns



### 3-9 in the ambient environment. Boron does not magnify through the food chain, but does accumulate in aquatic and t errestrial plants. While it is an essential micronutrient for higher plants, there is a small range between deficiency and toxicity in some plants. Studies of acute exposure to fish yielded toxicity values ranging from approximately 10 to 300 mg/L. Rainbow trout and zebra fish were the most sensitive. Mallard duckling growth was impacted at dietary levels of 30 and 300 milligrams per kilogram (mg/kg), while survival was reduced at 1,000 mg/kg [WHO, 1998].

EPA has not set a numerical criterion under the NRWQC for aquatic life, but it has issued a narrative criterion of 750 μg/L for sensitive crops that receive long- term irrigation.

EPA has not set a NRWQC for human health. Very few human studies have examined health effects resulting from boron exposure through oral ingestion. However, one study documents nausea, vomiting, and diarrhea in an adult male who ingested 85 mg/kg of boron (30 g as boric acid) [ ATSDR, 2010b]. In addition, animal experiments indicate that boron in the form

of boric acid and borate a ffect reproductive and developmental processes at levels that are approximately 100 to 1,000 times greater than normal exposure levels, approximately 1.2 milligrams per day (mg/day) [WHO, 1998].

Manganese

Manganese is a constituent in coal and other fuels, where it is usually—depending on the type of coal

— present at a higher concentration than other metals. Looking at a range of coal types (bituminous, subbituminous, and lignite) from across the country, the manganese concentration in coal ranges from 5.65 micrograms per gram ( μg/g ) in subbituminous coal from Wyoming to 259 μg/g in bituminous coal from Iowa. For comparison, the selenium

concentrations in these coals are 0.51 and 3.6 μg/g , respectively [U.S. EPA, 2000c].

In water, manganese tends to attach to particles or settle into the sediment [ATSDR, 2008b]. It occurs in both dissolved and suspended forms, depending on the water chemistry (e.g., pH) [WHO, 2011]. Manganese can bioaccumulate in lower organisms, such as phytoplankton, algae, mollusks, and some fish, but not in higher organisms. Studies suggest that biomagnification up the food chain is not significant [ATSDR, 2008b].

Due to a high bioaccumulation factor and concentrations in the edible portions of mollusks, there is a criterion to protect th e consumers of marine mollusks—100 μg/L for marine waters [U.S. EPA, 1986]. Although high levels can be toxic to humans, manganese is an essential nutrient required to maintain health and is generally not considered to be toxic when ingested [WHO, 2011]. EPA did not set a primary MCL for manganese in drinking water; however, EPA did set secondary (nonenforceable) standards at 50 μg/L to minimize objectionable qualities in the drinking water that lead to laundry stains and objectionable tastes in beverages.

3.1.2 Nutrients

Nutrients (e.g., phosphorus and nitrogen) are essential components for plants and animals to grow and develop; however, increased nutrient concentrations can upset the delicate balance of nutrient supply and demand required to maintain aquatic li fe in surface waters. For example,Section 3

— Environmental And Human Health Concerns



### 3-10 excess nutrients is one factor causing low oxygen in surface waters (h ypoxia) and hazardous algal blooms. These are primarily problems for estuaries, such as the Chesapeake Bay, and

coastal waters , such as the Gulf of Mex ico . Nutrient concentrations present in combustion wastewater are primarily attributed to the fuel composition and air pollution controls in the combustion process.

EPA estimates that annual nutrient loadings from the steam electric industry are currently 30.4 million pounds of total nitrogen and 682,000 pounds of phosphorus. Total nitrogen loadings

from coal -fired power plants could potentially increase significantly in the future as air pollution limits become stricter and air pollution control use increases. While the current concentration of nitrogen in combustion wastewater from an individual power plant can be relatively low, the total nitrogen load ings from a single plant can be significant due to high wastewater discharge

flow rates. Total nutrient loadings from multiple power plants is especially a concern on water bodies that are nutrient impaired or in watersheds that contribute to downstream nutrient problems. High nutrient loadings to receiving waters can affect the ecological stability of freshwater and saltwater aquatic systems; excessive levels of nutrients can stimulat e plant and algal growth that can obstruct sunlight penetration, increase turbidity, and lead to declining

disso lved oxygen levels. These aquatic changes can potentially kill bottom- dwelling aquatic plants.

3.1.3 TDS

TDS, a reflection of water’s salinity level, is a measure of the amount of dissolved matter

in water. TDS is comprised of primarily inorganic salts, as wel l as a small amount of organic matter. Common inorganic salts that can be found in water include cations (positively charged ions): calcium, magnesium, potassium and sodium; and anions (negatively charged ions): carbonates, nitrates, bicar bonates, chlorides, and sulfates. TDS concentrations in steam electric industry wastestreams include contributions from dissolved metals, chlorides, and bromides.

Dissolved metals and other TDS constituents are found in wastewater particularly at acidic pH

levels when they exhibit high solubilities. Negative impacts from TDS in combustion wastewater is attributable to the specific constituents that comprise the TDS in the discharge.

Bromides

Bromide is the anion of bromine; it commonly exists as salts with potassium and oth er cations, which are usually very soluble in water. It is commonly found in nature, with levels ranging from trace amounts to 0.5 mg/L in fresh water to 65 mg/L in seawater. The bromide ion has a low degree of toxicity, and animal testing suggests very lo w acute toxicity upon oral administration; accordingly, bromide is not of toxicological concern to humans [WHO, 2009].

While bromide itself is not thought to be toxic at levels present in the environment, its reaction with other constituents may be cause for concern. The bromide ion can form bromated, a disinfection byproduct (DBP), when drinking water plants use ozone to disinfect the source water. Bromide can also react with chlorine or chlorine-based disinfectants and naturally occurring organic matter in water to form brominated and mixed chloro-bromo DBPs, such as trihalomethanes or halogenated acetic acids [WHO, 2009]. EPA has set MCLs for DBPs:Section 3

— Environmental And Human Health Concerns



### 3-11 • 

### 0.010 mg/L for bromated due to increased cancer risk from long-term exposure;

• 

### 0.060 for haloacetic acids (HAAs) due to increased cancer risk from long- term exposure; and

• 

### 0.080 mg/L for total trihalomethanes (TTHMs) due to increased cancer risk and l iver, kidney or central nervous system problems from long-term exposure [U.S. EPA, 2009e].

Studies indicate that exposure to TTHMs and other DBPs from chlorinated water are associated with human bladder cancer [Villanueva et. al., 2004; Cantor et. al., 2010]. DBP formation is influenced by factors such as bromide ion concentration, pH of the sou rce water, the disinfectant dose (ozone or chlorine), reaction or contact time, and organic matter concentration and reactivity [Lin and Singer, 2003].

The city of Pittsburgh, in cooperation with the University of Pittsburgh, is currently conducting a study on the Allegheny River to determine the major sources of bromide discharges, inclu ding coal -fired power plants. Typically, bromide concentrations are very low in the river, but there are increased levels near industrial sites. EPA is currently examining the effects of bromide concentration on TTHMs to determine an acceptable level of bromide in a water body [U.S. EPA, 2012a]. Drinking water utilities are concerned as well, noting that the bromide concentrations have made it increasingly difficult for them to meet Safe Drinking Water Act requirements for TTHMs [ U.S. EPA, 2012 a].

Chloride s

Chloride levels in combustion wastewater are dependent upon chlorine concentrations present in the parent coal as well as the amount of recirculation in the FGD system. FGD systems with many iterations of circulation between blowdown cycles exhibit high concentrations of chlorides. In addition, studies have

found that combustion wastewater leachate reaching ground water has caused chloride levels to exceed secondary MCLs [NRC, 2006]. Chlorides contribute to the high TDS levels typical of combustion wastewater, as do c alcium and magnesium. Both ch loride and TDS levels affect the availability and toxicity of other

combustion wastewater constituents, including metals. As TDS and chloride levels fluctuate, so do the amounts of other metals that dissolve due to solubility characteristics.

EPA recommend s the following for chloride: criterion maximum concentration of 860 mg/L (acute effects) and criterion continuous concentration of 230 mg/L (chronic effects) [U.S. EPA, 2009d] . Exceeding these chloride levels in wastewater discharges can be harmful to

ani mals and plants in non- marine surface waters and can disrupt ecosystem structure. It can also adversely affect biological wastewater treatment processes. Furthermore, excessively high chloride concentrations in surface waters can impair their use as source waters for potable water supplies. If sodium is the predominant cation present, the water will have an unpleasant taste due

to the corrosive action of chloride ions. Pollutant Loadings from Steam

Electric Power Plants

• 5,500,000,000 pounds of pollutants

per year.



### • 8, 300,000 pounds of toxic

weighted pound equivalents (TWPE) per year.Section 3

— Environmental And Human Health Concerns



### 3-12 3.2 L OADINGS 

### A SSOCIATED WITH 

### C OMBUSTION 

### W ASTEWATER



### As discussed above, the pollutants commonly found in combustion wastewater such as metals, nutrients and TDS (including bromides and chlorides) can cause considerable harm to surface waters, aquatic life, wildlife, and human health. The total pollutant loadings from steam electric power plants a re significant with the steam electric power sector accounting for at least 50 to 60 percent of the toxic pollutants reported to be discharged in industrial National Pollutant Discharge Elimination System (NPDES) permits [ERG, 2012g] . EPA estimate d the amo unt of pollutants (i.e., loadings) discharged by steam electric power plants throughout the United States

as over 8 million toxic weighted pound equivalents (TWPE) 4 

### annually in the waste streams

evaluated and considered as part of the revision to the Steam Electric ELGs. When coupled with

the types of impacts associated with the pollutants , the amount of the load ings raises concern about the risks that these discharges present to the aquatic environment and the surrounding ecosystem. This section presents t he annual baseline (i.e., current) pollutant loadings associated with the evaluated waste streams and compares steam electric discharges to those of other industries to provide perspective on the magnitude of the loadings and subsequent potential impact th ese waste streams pose to the environment. In addition, this section discusses the Chesapeake Bay and Great Lakes as example sensitive environments that receive substantial pollutant loadings from steam electric power plant discharges.

3.2.1 Annual Baseline Pol lutant Loadings

As part of its effluent guidelines development process, EPA estimate d the pollutant loadings discharged from steam electric power plants for the evaluated waste streams, as

described in Section 10 of the TDD

. Table 3-2 presents the baseline annual pollutant loadings discharge d for select pollutants considered for analysis in the EA. 5 

### EPA presents these loadings in terms of pounds and TWPE and lists the TWF where applicable. The pollutants with the highest annual TWPE discharges are arsenic, boron, cadmium, manganese, mercury, and

selenium. Although the total pounds discharged of arsenic, cadmium, and mercury are lower than other pollutants, their relative to xicity (as represented by the TWF) result in a large TWPE. Other pollutants, such as boron and manganese, are relatively low in toxicity but due to the relatively high amount of these pollutants in the combustion wastewaters, their resulting TWPE is high. The high TWPE for selenium results from a combination of its quantity discharged in

combustion wastewaters and its TWF.

4 To calculate the TWPE, EPA multiplies a mass loading of a pollutant in pounds per year (lb/yr) by a pollutant

specific weighting factor, called the toxic weighting factor (TWF), to derive a "toxic

- equivalent" loading (lb

equivalent/yr), or TWPE. TWFs account for differences in toxi city across pollutants and provide the means to compare mass loadings of different pollutants on the basis of their toxic potential. EPA has developed TWFs for more than 1,900 pollutants based on aquatic life and human health toxicity data, as well as phys ical/chemical property data [U.S. EPA, 2006a].

5 Almost half of the 8 million TWPE discharged in the evaluated waste streams is from additional pollutants not presented in Table 3-2 . For the EA, EPA focused on the pollutants listed in the table due to a number of factors: metal is present in the evaluated waste streams (see Table 2-1 ), elevated levels have been observed in surface waters or wildlife from exposure to combustion wastewater, and amount of the individual pollutant loadings to receiving waters. See the TDD for a complete listing of baselin e pollutant loadings.Section 3

— Environmental And Human Health Concerns



### 3-13 Table 3-2. Annual Baseline Pollutant Discharges from the Steam Electric Industry

Pollutant a TWF b Annual Discharge, pounds (lbs) Annual TWPE, pound

equivalent (lb

- eq)

Metals
Manganese 0.07043 14,500,000 1,020,000

Cadmium 23.1168 31,900 738,000

Boron 0.00834 54,300,000 453,000
Mercury 117.118 2,820 330,000

Arsenic 4.0413 79,200 320,000

Selenium 1.1213 225,000 252,000

Thallium 1.0271 164,000 168,000

Lead 2.24 64,400 144,000

Aluminum 0.0647 1,970,000 128,000
Copper 0.6348 69,900 44,400

Nickel 0.1089 287,000 31,200

Iron 0.0056 4,990,000 27,900

Zinc 0.0469 393,000 18,400

Chromium VI 0.5166 11,800 6,090

Vanadium 0.035 158,000 5,530

Total Metals c 1,790,000,000 4,800,000

Nutrients Total Nitrogen Not applicable 30,400,000 Not applicable
Total Phosphorus Not applicable 682,000 Not applicable

Other

Chlorides 2.435 X 10 - 05 1,640,000,000 39,800

Total Pollutants c,d 5

, 5 00,000,000 8,320,000

Sources : ERG, 2013c; U.S. EPA, 2006a.

a – The list of pollutants included in this table is only a subset of pollutants included in the loadings analysis (see Section 10 of the TDD).

b

– TWFs for the following metals apply to all metal compounds: arsenic, chromium, copper, lead, manganese, mercury, nickel, selenium, thallium, vanadium, and zinc. EPA updated TWFs for boron, chlorides, chromium compounds, and iron for the S team E lectric ELGs pollutant loadings analysis.

c – To avoid double

- counting of dissolved metals, the totals include all pollutants from the loadings analysis with the exception of TDS. Annual baseline discharges of TDS from the evaluated waste streams total approximate ly 7,120,000,000 pounds.

d

– The totals represent the pollutant loadings in discharges of the evaluated waste streams

– specifically, FGD wastewater, fly ash transport wastewater, bottom ash transport wastewater, and leachate (see Section 10 of the TDD).Section 3

— Environmental And Human Health Concerns



### 3.2.2 Com parison of Steam Electric Loadings to Other Industries

The total TWPE discharges from the steam electric industry are higher than the TWPEs estimated for many other industries. A s part of the Preliminary

2010 Plan published on October 30, 2009 (74 FR 68599)

, EPA identified 10 point source categories

, out of 56 categories, that represented the bulk of the

estimated toxic wastewater discharges (as measured by TWPE) from existing industrial point source categories. EPA ranked each point source category by

the amount of toxic pollutants in its discharges and identified the Steam Electric Power Generating Point Source Category (40 CFR 423) as the category with the highest TWPE. Table 3-3 presents the total TWPE estimated as part of the 2010 Effluent Guidelines Planning Process for the remaining nine point source categories with the highest TWPE [U.S. EPA, 2011d]. EPA estimate d that the total baseline TWPE from combustion wastewater (see Table 3-2 ) is over eight times the amount estimated for the pulp, paper, and paperboard industry and petroleum refining industry (second and third highest ranking) and over 10 times the TWPE for seven of the eight other industries identified as the top TWPE dischargers in the Final 2010 Plan [U.S. EPA, 2011d]. 6 

### This suggests that the loadings from the subset of evaluated waste streams represent a greater environmental concern within the context of all industrial dischargers across the United States.

Table 3-3

. Pollutant Loadings for the Final 2010 Effluent Guidelines Planning Process : Top 10 Point Source Categories Pollutan t Loadings: How D oes the Steam Electric Industry Compare?

E PA estimates that discharges from steam electric power plants alone contribute at least 50 to 60 percent of the toxic weighted pound equivalent (TWPE) pollutant loadings to the environment among all industrial categories that report discharges under

NPDES permits.

40 CFR Part Point Source Category Total TWPE
(lb

- eq/yr)

423 Steam Electric Industry 8 ,320,000 a

430 Pulp, Paper And Paperboard 1,030,000

419 Petroleum Refining 1,030,000

421 Nonferrous Metals Manufacturing 994,000

418 Fertilizer Manufacturing 826,000

414 Organic Chemicals, Plastics And Synthetic Fibers 649,000

440 Ore Mining And Dres sing 448,000

415 Inorganic Chemicals Manufacturing 299,000

44 4 Waste Combustors 254,000

410 Textile Mills 250,000

Source : U.S. EPA, 2011d.

a – As presented in Table 3-2 , EPA calculated the Steam Electric Indust ry (40 CFR 423) discharges for the proposed ELGs analysis to total 8,320,000 TWPE annually

.

6 Data sources for the other industry discharges include Discharge Monitor ing Reports (DMRs) and Toxic Release Inventory (TRI) reports. EPA recognizes that the DMR and TRI data have limitations (e.g., only a subset of facilities and a subset of pollutants might be included in the estimated loadings); however, these are the most readily available data sets that represent discharges across the United States.



### 3-14Section 3

— Environmental And Human Health Concerns



### 3-15 3.2.3 Comparison of Steam Electric Loadings to Publicly Owned Treatment Works

To provide additional perspective on the magnitude of the pollutant loadings from steam electric power plants, EPA compared loadings for the evaluated waste streams to those of an average publicly owned treatment works (POTW). EPA selected POTWs for compar ison

because , for point sources, POTWs and steam electric plants dwarf all other point source discharges in terms of total TWPE of metals discharged to waters in the United States [U.S. EPA, 2010c]. 7 

### In addition, the over 16,000 POT Ws are located across th e United States, are

known to have consistent wastewater influent characteristics , and are a common metric used for point source evaluations.

EPA calculated the average pollutant loadings discharged from a typical POTW using

EPA’s Effluent Guidelines Prog ram Plan DMR database, DMRLoadsAnalysis2009_v02.mdb. EPA assumed a typical POTW to discharge wastewater at a rate of 3 to 5 million gallons per day (MGD) 8 

### based on the number of facilities by discharge flow rate reported in Metcalf and Eddy, 2003 [ERG, 201 2c] . EPA developed queries in the DMRLoadsAnalysis2009_v02.mdb to 1) select POTWs that discharge between 3 and 5 MGD and 2) calculate the average DMR loadings (in pounds and TWPE per year) for each pollutant [ERG, 2012c]. Table 3-4 compares the average steam electric pollutant loadings by waste stream to the pollutant loadings from an average POTW assumed to discharge 3 to 5 MGD. The results of the analysis demonstrate the following:

• 

### Average FGD wastewater discharges contain more than 250 times more boron and over 300 times more manganese.

• 

### Average FGD wastewater discharges contain more than 80 times more selenium.

7 Based on metal loadings (total TWPE) calculated by EPA’s DMR Pollutant Loadin g Tool, 2010 data, by Standard Industrial Classification (SIC) code. The top two industries are SIC 4952

– sewerage systems (i.e., POTWs) and SIC

4911

– electrical services.

EPA’s DMR Pollutant Loading Tool is an online tool ( http://cfpub.epa.gov/dmr/ ) that calculates pollutant loadings from permit and DMR data from EPA‘s Permit Compliance System (PCS) and Integrated Compliance Information System for the National Pollutant Discharge Elimination System (ICIS

- NPDES). The tool also ranks dischargers, industries, and watersheds based on pollutant mass and toxicity, and presents “top 10” lists to help users determine which facilities and industries are producing these discharges and which watersheds are impacted. Facilities report pollutant discharge monitoring data in their DMR as mass

- based quantities (e.g., pounds per day) and/or concentrations (e.g., mg/L). The DMR Pollutant Loading Tool allows users to gather annual loadings data. For this
EA, EPA reviewed the 2010 lo adings reported in DMRs.

The use of the DMR data has its limitations. Only pollutants included in the facility’s NPDES permit are included in

the PCS and ICIS

- NPDES databases; therefore, if a facility does not have mercury limitations, mercury discharges from that facility will not be included in the total for industrial discharges. States (or other permitting authority) have some discretion as to which data they make available (or enter) to PCS and ICIS

- NPDES. For example, permitting

authorities enter DMR and permit information for facilities that are considered major dischargers. However, they do not necessarily enter DMR or permit information into PCS for minor dischargers or facilities covered by a general permit.

8 For comparison, the average discharge flow rate for the steam electric waste streams of concern are 0.5 MGD for FGD wastewater; 2.4 MGD for fly ash sluice water; 1.8 MGD for bottom ash sluice water; and 0.06 MGD for leachate (U.S. EPA, 2012b).Section 3

— Environmental And Human Health Concerns



### 3-16 • 

### Average FGD wastewater discharges contain more than 30 ti mes more cadmium and

nickel.

• 

### Loadings in fly ash transport water have more than 10 times more arsenic, boron, cadmium, manganese, and selenium.

• 

### Loadings in fly ash transport water have 30 times more thallium.

• 

### Loadings in the bottom ash transport water have 40 times more thallium.

• 

### Loadings in the bottom ash transport water have over 10 times more nickel.

• 

### Only boron, iron, manganese, and selenium in the average leachate wastewater discharges showed higher loadings than the average POTW.

Nutrient loadings (to tal nitrogen and total phosphorus) from the average steam electric

waste streams of concern are similar in magnitude to the nutrient loadings from an average POTW. Total nitrogen loadings from an average FGD waste stream are similar to those of an

average POTW. Nitrogen loadings from average fly ash and bottom ash transport waters are each equivalent to about one-third the amount of total nitrogen from an average POTW. The amount of total phosphorus discharged by an average POTW is 10 to 30 times higher than that in the average FGD wastewater, fly ash transport water, and bottom ash transport water discharges. EPA did not calculate nutrient loadings for leachate.

For chlorides , EPA found that a verage FGD wastewater discharges contain approximately 8 times

gr eater chloride loadings than an average POTW discharge

. The a verage discharge of fly ash transport

water , bottom ash transport water, and leachate

wastewater from a steam electric power plant contains less chlorides than a typical POTW discharge. EPA’s DMR data did not include pollutant loadings for TDS from POTWs; therefore, EPA could not compare these pollutant loadings between steam electric and POTW discharges

.

To provide additional perspective on the magnitude of the loadings, EPA calculated the equivalent number of typical POTWs that would discharge loadings equal to the 290 steam electric power plants included in the baseline loadings analysis. Table 3-5 presents total pollutant loadings for the waste streams of concern (for the 290 plants) and the number of typical POTWs that would discharge equivalent loadings. The results demonstrate that the magnitude of the total loadings from 290 steam electric power plants is equivalent to a significantly larger number of typical POTWs for many of the pollutants commonly known to cause environmental harm. For example, EPA estimate d that combustion wastewaters from the 290 steam electric power plants discharge loadings equivalent to over 10,000 POTW discharges of boron, manganese, selenium, and thallium, and over 1,000 POTW discharges of arsenic, cadmium, iron, lead, nickel and Steam Electri c Industry Loadings Compared to POTWs

• FGD wastewater discharges

contain

- 300 times more manganese

- 250 times more boron

- 80 times more selenium

- 30 times more nickel

- 30 times more cadmium

• Bottom ash transport water discharges contain 40 times more

thallium and over 10 times more

nickel.



### • Fly ash transport water discharges contain 10 times more arsenic, boron, cadmium, manganese, and

selenium and 30 times more

thallium.Section 3

— Environmental And Human Health Concerns



### 3-17 chlorides . This suggests that, for the evaluated waste streams, 290 steam electric plants contribute substantial pollutant loadings to the environment, even when compared to over 50,000

POTWs in the United States.3-18 Section 3

— Environmental And Human Health Concerns



### Table 3-4. Comparison of Average Pollutant Loadings in the Evaluated Waste Streams to an Average POTW

Pollutant Average Plant FGD Discharge a,b Average Plant Fly Ash Discharge a,c Average Plant Bottom Ash Discharge a,d Average Plant Leachate Discharge a,e Average POTW Discharge a,f

Loadings

(lbs/yr) TWPE
(lb

- eq/yr) Loadings (lbs/yr) TWPE (lb

eq/yr) Loadings (lbs/yr) TWPE (lb

- eq/yr) Loadings (lbs/yr) TWPE
(lb

- eq/yr) Loadings (lbs/yr) TWPE (lb

- eq/yr)

Aluminum 2,500 162 7,660 495 2,220 144 1,110 71.9 3,590 215

Arsenic 10.1 40.9 479 1,940 69 279 11.1 44.7 46 186

Boron 410,000 3,420 18,900 158 8,330 69.5 4,780 39.8 1,540 13

Cadmium 133 3,070 58.6 1,350 30.5 705 0.594 13.7 4 82

Chromium VI 6.7 3.46 77.6 40.1 7.95 4.11 (g) (g) 18 9

Copper 26.1 16.6 280 178 113 72 2.11 1.34 154 97

Iron 1,850 10.4 5,850 32.7 8,610 48.2 15,100 84.4 2,530 14

Lead 5.93 13.3 206 461 134 299 0.335 0.751 49 109

Manganese 115,000 8,090 3,680 259 680 47.9 1,050 74.2 354 25

Mercury 6.58 771 8.65 1,010 3.33 390 0.26 30.4 3,180 372,000

Nickel 1,030 112 239 26.1 451 49.1 16.6 1.81 31 3

Selenium 1,490 1,670 257 289 44.7 50.2 20.5 23 18 21

Thallium 19.3 19.8 300 308 427 439 0.359 0.369 10 10

Vanadium 25.9 0.908 428 15 50.7 1.77 876 30.7 no data no data

Zinc 1,630 76.7 790 37 338 15.9 40.1 1.88 453 18

Total Nitrogen 109,000

- 39,000

- 39,400

- (g)

- 123,000

- Total Phosphorus 651

- 1,810

- 1,320

- (g)

- 17,800

-

Chlorides 12,800,000 311 265,000 6.46 187,000 4.55 155,000 3.78 1,610,000

- TDS 44,100,000

- 3,690,000

- 4,350,000

- 993,000

- no data no data

a – All values are rounded to three significant figures.

b

– Average FGD loadings based on 117 plants assumed to discharge FGD wastewater under baseline conditions [ERG, 2013c]

.

c – Average fly ash loadings based on 93 plants assumed to discharge fly ash sluice under baseline conditions [ERG, 2013c]

. d

– Average bottom ash loadings based on 244 plants assumed to discharge bottom ash sluice under baseline conditions [ERG, 2013c]

.

e – Average leachate loadings based on 102 plants assumed to discharge leachate under baseline conditions [ERG, 2013c]

. f

– Average POTW loadings based on average loadings calculated by DMRLoadsAnalysis2009_v02.mdb (DCN SE01961) for POTWs discharging 3 to 5 MGD

of wastewater.

g – EPA did not calculate loadings for this pollutant and waste stream. See Section 10 of the TDD.Section 3

— Environmental And Human Health Concerns



### 3-19 Table 3-5. Estimated Number of POTW Equivalents for Total Pollutant Loadings from the

Evaluated Waste Streams

Pollutant Annual Discharge pounds (lbs) a Equivalent Number of Average

POTWs b

Aluminum 1,970,000 550

Arsenic 79,200 1,720

Boron 54,300,000 35,300

Cadmium 31,900 7,980

Chromium VI 11,800 655
Copper 69,900 454

Iron 4,990,000 1,970

Lead 64,400 1,320
Manganese 14,500,000 41,000
Mercury 2,820 <1

Nickel 287,000 9,250

Selenium 225,000 12,500

Thallium 164,000 16,400

Vanadium 158,000 No values for comparison

Zinc 393,000 868
Total Nitrogen 30,400,000 247
Total Phosphorus 682,000 38

Chlorides 1,640,000,000 1,020

TDS 7,120,000,000 No values for comparison

a – ERG, 2013c

. b

– Equivalent number of POTWs is estimated by divi di ng the total annual pollutant load ings by the average POTW loadings presented in Table 3-4 for a 4

- MGD POTW.



### 3.2.4 Pollutant Loadings to the Chesapeake Bay Watershed

Most of the Chesapeake Bay and its tidal

waters are listed as impaired for excess nitrogen, phosphorus, and s ediment. These pollutants cause

oxygen -consuming algae blooms and create “dead zones” where fish and shellfish cannot survive, block sunlight that is needed for underwater grasses, and smother aquatic life on the bottom of the Bay

. To restore water quality in the Bay, EPA

established Total Maximum Daily Load (TMDL)

limits for the Chesapeake Bay watershed in

December 2010. These limits are of 186 million pounds of nitrogen, 12.5 million pounds of phosphorus, and 6.45 billion pounds of sediment each year, reducing the discharges to the watershed by 25 percent for nitrogen, 24 percent for phosphorus, and 20 percent for sediment. Pollutant loadings to the Chesapeake Bay watershed come from both point sources and nonpoint sources. Point sources include municipal wastewater facilities, industrial discharge facilities (e.g., steam electric power plants and concentrated animal feeding operations), National Pollutant Discharge Elimination System ( NPDES ) permitted stormwater ( m unicipal separate

st orm s ewer s ystem s (MS4) and construction and industrial sites), and other sources. Nonpoint Steam Electric Industry Annual Discharges to the Chesapeake Bay

• 2.2 million pounds of total nitrogen

• 21,500 pounds of zinc

• 5,180 pounds of arsenic

• 1,820 pounds of cadmium



### • 168 pounds of mercurySection 3

— Environmental And Human Health Concerns



### 3-20 sources include agricultural land runoff, atmospheric deposition, forest land runoff, nonregulated stormwater runoff, stream banks and tidal shorelines, tidal resuspension, the ocean, wildlife, and natural background [U.S. EPA, 2010d].

EPA identified 1,679 NPDES-p ermitted facilities discharging industrial wastewaters in the Chesapeake Bay watershed. In 2009, these facilities contributed an estimated 7.3 million pounds of total nitrogen and 1.27 million pounds of total phosphorus to the Bay, an estimated

3 percent a nd 8 percent, respectively, of all nitrogen and phosphorus loadings delivered to Chesapeake Bay watershed [U.S. EPA, 2010d ]. EPA identified 20 steam electric power plants discharging to the Chesapeake Bay watershed and estimate d that these plants discharge 2.2 million pounds of nitrogen and 60,000 pounds of phosphorus to the Bay annually [ ERG,

2013c ]. This suggests that the evaluated waste streams from steam electric power plants contribute 30 percent of the total nitrogen loadings and approximately 5 perce nt of the total phosphorus loadings to the Chesapeake Bay from NPDES-permitted sources [ERG, 2013 c].

Historically, studies of water quality issues in the Chesapeake Bay have focused on nutrients; however, in 1999 EPA assessed the impact of toxic pollutants entering the Bay including some metals found in steam electric power plant discharges (e.g., arsenic, cadmium, copper, lead, mercury, and zinc). Although EPA concluded that the majority of impacts were localized issues, EPA estimated the total metal pollu tant loadings from point sources discharging to the Bay. Table 3-6 presents the baseline pollutant loadings for the evaluated waste streams and

the es timated loadings from all point sources to the Chesapeake Bay watershed. The results indicate that pollutant loadings from the evaluated waste streams represent a large portion of the point source metal loadings to the Chesapeake Bay watershed for arsenic, cadmium, lead, and

zinc.

Table 3-6. Comparison of Steam Electric Pollutant Loadings to Other Point Source Discharges to the Chesapeake Bay Watershed

Pollutant Steam Electric Baseline Loadings to the Chesapeake Bay Watershed (lbs/year) a Total Point Source Loadings to the Chesapeake Bay Watershed (lbs/year) b,c Percentage of Point Source Loadings from

Steam Electric Plants

Arsenic 5,180 3,500 (c) 100%

Cadmium 1,820 3,000 (c) 61%
Copper 5,150 78,100 (c) 7%

Lead 5,630 15,000 (c) 38%
Mercury 168 2,660 (c) 6%

Zinc 21,500 125,000 (c) 17%
Total Nitrogen 2,200,000 7,340,000 (b) 30%
Total Phosphorus 60,000 1,270,000 (b) 5%

a

– ERG, 2013c

.
b

– U.S. EPA, 2010 d

.

c – Chesapeake Bay Program, 1999.



### The estimated total point source loadings of arsenic from the 1999 Chesapeake Bay Basin Toxics Loading and Release Inventory [Chesapeake Bay Program, 1999] was less than the estimated amount of arsenic discharged from the 20 steam electric power plants. ThisSection 3

— Environmental And Human Health Concerns



### 3-21 inconsistency may be due to incomplete data sets. In the report, the Program noted that point source loadings are based on best available data and estimated only for major facilities (facilities with a flow of 0.5 million gallons per day or greater) included in EPA’s Permit Compliance System (PCS). As part of their NPDES permits, many point sources are not required to monitor for arsenic and other pollutants associated with the waste streams of concern; therefore, the report might not account for these pollutant loadings. In addition, the data are also over 10 years old and metal pollutant loadings to the Bay may have changed during that time (i.e., increased arsenic discharges).

To provide additional perspective on the magnitude of the loadings, EPA calculated the equivalent number of typical POTWs that would discharge loadings equal to the 20 steam electric power plants that discharge to the Chesapeake Bay wa tershed. Table 3-7 presents total pollutant loadings for the evaluated waste streams discharging to the Chesapeake Bay and the number of typical POTWs that would discharge equivalent loadings.

Table 3-7 . Estimated Number of POTW Equivalents for Pollutant Loadings to the Chesapeake Bay Watershed from the Evaluated Waste Streams

Pollutant Annual Discharge to the Chesapeake Bay Watershed, pounds (lbs) a Equivalent Number of Typical

POTWs b

Arsenic 5,180 113

Cadmium 1,820 455

Chromium VI 681 38
Copper 5,150 33

Lead 5,630 115
Mercury 168 <1

Nickel 20,700 668

Selenium 10,100 561

Thallium 16,700 1,670

Zinc 21,500 48
Total Nitrogen 2,200,000 18
Total Phosphorus 60,000 3

a – ERG, 2013c

. b

– Equivalent number of POTWs is estimated by dividing the total annual pollutant loadings to the Chesapeake Bay by the average POTW loadings presented in Table 3-4 for a 4

- MGD POTW.



### The results demonstrate that the magnitude of the total loadings from 20 steam electric power plants discharging to the Chesapeake Bay is equivalent to:

• 

### Over 100 typical POTW discharge s of arsenic and lead;

• 

### Over 450 typical POTW discharge s of cadmium ;

• 

### Over 550 typical POTW discharges of nickel and selenium; and

• 

### Over 1,600 typical POTW discharges of thallium.

This suggests that, for the evaluated waste streams, 20 steam electric plants contribute

substantial metal load ings to the Chesapeake Bay when compared to typical POTW discharges.Section 3

— Environmental And Human Health Concerns



### 3-22 3.2.5 Pollutant Loadings to the Great Lakes Watershed

Environmental impacts documented in the Great Lakes are associated with a range of stressors, including toxic and nutrient pollutants, invasive species, and habitat degradation. EPA and Environment Canada have focused their Great Lakes Binational Toxics Strategy on persistent toxic substances such as mercury [U.S. EPA and Environment Canada, 1997]. Mercury is a concern in all of the Great Lak es due to its bioaccumulation in fish and wildlife and potential impacts on humans. For example, in a study of 65 hair samples from fish

- eating and

non- fish

- eating women, average mercury concentration s in hair were significantly greater (i.e., 128 to 443 percent higher concentration) for women who ate several meals of sport

- caught fish from the Great Lakes. EPA and Environment Canada have documented a range of wildlife impacts from mercury in the Great Lakes such as an increase of physiological abnormalitie s in herring gulls [U.S. EPA and Environment Canada, 2009].

The primary source of mercury in the Great Lakes watershed is atmospheric deposition from sources around the Great Lakes watershed (e.g., fuel combustion, incineration, and manufacturing) emitting approximately 70,000 pounds of mercury annually [Evers et. al., 2011]. When compared to atmospheric deposition, mercury contributions from point source discharges are less of a concern. Due to the bioaccumulative nature of mercury, EPA has placed strict controls (e.g., mixing zones are not al lowed in permits) to limit the total amount of mercury entering the Great Lakes watershed. Monitoring within the Great Lakes watershed has indicated a decrease in mercury point source discharges, primarily because of implemented control strategies.

EPA ide ntified 26 steam electric power plants discharging to the Great Lakes watershed with the majority discharging to Lake Michigan (14 plants) and Lake Erie ( 4 plants) [ ERG, 2013c]. In the Lake Erie Management Plan, EPA identified steam electric discharges as contributing 57 percent of the mercury to the Lake Erie from wastewater sources [U.S. EPA, 2008b].

Table 3-8 presents the loadings from steam electric power plants discharging to the Great Lakes watershed. EPA did not identify any documented analysis of total point source discharges to the Great Lakes to use as a comparison to the steam electric loadings. EPA did identify data on nutrient loadings to th e Great Lakes watershed; the comparison of steam electric loadings to total nutrient discharges is presented after Table 3-8 . When evaluating impacts from

bioaccumula tive pollutants, t he potential for pollutant retention in still or slow -moving water, such as the Great Lakes, is a particular concern . Many pollutants in combustion wastewater can bioaccumulate in fish and then affect higher trophic levels and terrestrial environments. Steam Electric Industry Annual Discharges to the Great Lakes

• 2 million pounds of total nitrogen

• 19,800 pounds of zinc

• 6,240 pounds of selenium

• 4,170 pounds of arsenic

• 1,410 pounds of cadmium



### • 117 pounds of mercurySection 3

— Environmental And Human Health Concerns



### 3-23 Table 3-8. Steam Electric Pollutant Loadings to the Great Lakes Watershed

Pollutant Steam Electric Baseline Loadings to the Great Lakes Watershed (lbs/year)

Arsenic 4,170

Cadmium 1,410

Chromium VI 380
Copper 5,180

Lead 5,840
Mercury 117

Nickel 18,300

Selenium 6,240

Thallium 15,900

Zinc 19,800
Total Nitrogen 1,990,000
Total Phosphorus 53,200

Source: ERG, 2013c

.



### Nutrients in the Great Lakes also cause ecological issues (i.e., eutrophication). Due to this concern, Robertson and Saad [2011] used the SPARROW (SPAtially Referenced Regressions

On Watershed attributes) model to calculate discharges of nitrogen and phosphorus loadings to the Great Lakes using long -term mean annual loadings (normalized to base year 2002). The nitrogen and phosphorus loadings from all sources in the United States (including non-point sources) to the Great Lakes were 608 million and 25 million pounds, respectively. Depending on the specific lake, point sources contributed between 14 and 44 percent of total phosphorus loadings and between 13 and 34 percent of total nitrog en loadings in the Great Lakes [Robertson and Saad, 2011].

The total phosphorus loadings from U.S. point sources to the Great Lakes watershed is 4.8 million pounds; the steam electric industry contributes approximately 1 percent of the point source discharges for phosphorus. EPA estimated the total nitrogen loadings from point sources to be between 79 and 207 million pounds per year 9



### [Robertson and Saad, 2011]; the steam electric industry contributes between 2.5 and less than one percent of the point source loadings for nitrogen.

To provide additional perspective on the magnitude of the loadings, EPA calculated the equivalent number of typical POTWs that would discharge a loadings equal to the 26 steam electric power plants that discharge to the Great Lake s. Table 3-9 presents total pollutant

9 Depending on the lake, point sources represent between 13 to 34 percent of the total nitrogen loading to the Great Lakes (values not provided in reference by lake name). 

### Industry Loadings to the Great Lakes Compared to POTWs

26 steam electric power plants discharge to the Great Lakes. Loadings from these plants are equivalent to:

• Over 1,500 typical POTW discharges of thallium;

• Over 550 typical POTW discharges of nickel;

• Over 350 typical POTW discharges of cadmium;

• Over 300 typical POTW discharges of selenium;

• Over 100 typical POTW discharges

of lead.Section 3

— Environmental And Human Health Concerns



### 3-24 loadings for the evaluated waste streams discharging to the Great Lakes and the number of typical POTWs that would discharge equivalent loadings.

Table 3-9. Estimated Number of POTW Equivalents for Pollutant Loadings to the Great

Lakes from the Evaluated Waste Streams

Pollutant Annual Discharge to the Great Lakes, pounds (lbs) a Equi valent Number of Average

POTWs b

Arsenic 4,170 91

Cadmium 1,410 352

Chromium VI 380 21
Copper 5,180 34

Lead 5,840 119
Mercury 117 <1

Nickel 18,300 591

Selenium 6,240 347

Thallium 15,900 1,590

Zinc 19,800 44
Total Nitrogen 1,990,000 16

Total Phosphorus 53,200 3

a – ERG, 2013c

. b

– Equivalent number of POTWs is estimated by dividing the annual pollutant loadings to Great Lakes by the average POTW loadings presented in Table 3-4 for a 4

- MGD POTW.



### The results demonstrate that the magnitude of the total loadings from 26 steam electric power plants discharging to the Great Lakes is equivalent to a significantly larger number of typical POTWs f or many of the pollutants commonly known to cause environmental harm.

These 26 plants discharge a loadings equivalent to:

• 

### Over 1,500 typical POTW discharges of thallium;

• 

### Over 550 typical POTW discharges of nickel;

• 

### Approximately 350 typical POTW discharges of cadmium and selenium;

• 

### Over 100 typical POTW discharges of lead.

This suggests that, for the evaluated waste streams, 26 steam electric plants contribute substantial metal loadings to the Great Lakes when compared to typical POTW discharges.

3.3 L ONG 

### E NVIRON MENTAL 

### R ECOVERY 

### T IMES 

### A SSOCIATED WITH 

### P OLLUTANTS IN 

### S TEAM


### E LECTRIC 

### W ASTE 

### S TREAMS



### Recovery of the environment from exposure to combustion wastewater is affected by continued cycling of contaminants within the eco system , bioaccumulation, and the potential

a lterations to ecological processes

, such as population and community dynamics in the surrounding ecosystems. The ability of aquatic and adjacent terrestrial environments to recover from even short periods of exposure to combustion wastewater depends on the distance from discharge, the pollutant concentrations, pollutant residence time, and the time elapsed since exposure. In particular, accumulation of metals in sediments can slow recovery of aquaticSection 3

— Environmental And Human Health Concerns



### 3-25 systems following exposure to combustion wastewater due to the potential for resuspension in the water column and for benthic organisms to provide a pathway for exposure long after combustion wastewater discharges have ended. For example, Lemly [1985, 1997, 1999] documented that benthic pathways can continue to provide toxic doses of selenium to wild life even 10 years

after water column selenium concentratio ns are below levels of concern. Ruhl [2012] documented elevated levels of combustion wastewater pollutants (including arsenic and selenium) in pore water, even

in cases where the water column conce ntrations are not elevated. This study found that arsenic is retained in lake sediments and pore water through a cycle of adsorption and desorption, likely in response to seasonal changes in the lake water chemistry [Ruhl, 2012].

As discussed in Section 3.1 , many of the pollutants in combustion wastewater (e.g., arsenic, mercury, selenium) readily bioaccumulate in exposed biota. The bioaccumulation of these pollutants is of particular concern due to the ir potential for impacting higher trophic levels, local terrestrial environments, and transient species, in addition to the aquatic organisms directly exposed to the wastewater. Aquatic systems with long residence times and potential

contamination with bioaccumulative pollutants often experience persisten t environmental effects following exposure to combustion wastewater.

Population decline attributed to exposure to combustion wastewater can alter the structure of aquatic communities and cause casca ding effects within the food web that result in long- term impacts to ecosystem dynamics [Rowe et al., 2002]. Reductions in organism survival rates from abnormalities caused by exposure to combustion wastewater and alterations in interspecies relationships , such as declines in the abundance or quality of prey, can delay ecosystem recovery until key organisms within the food web return to levels prior to combustion

wastewater exposure. In a 1980 study of Rocky Run Creek by Forbes and Magnuson, fungal decompos ition of detritus was limited due to the effects of combustion wastewater . As a result,

the benthic invertebrate population , which graze on detrital material, declined as did benthic fish that prey upon small invertebrates due to a

re duction in available r esources [ Forbes and Magnuson, 1980].

Belews Lake, a 1,500

- hectare cooling

reservoir constr ucted to support the Belews Creek Steam Station in Stokes County, North Carolina, is a well

- documented case study that highlights the effects combustion wastewater

can have on fish populations and the subsequent long recovery time. In 1970, Duke Power began monitoring the fish populations in Belews Lake prior to any discharges of

combustion wastewater . From 1974 to 1985, Duke Energy discharged ash pond effluent into Belews Lake. Almost immediately after these Short Exposures to Combustion

Wastewater Can E quate to Lasting Ecological Effects

In Martin Lake, ecological effects persisted for at least eight years following eight months of fly ash discharges into the lake.

Studies have linked historical discharges of selenium from the Belews Creek Steam Station with persistent ecological impacts in the plant’s cooling reservoir.Section 3

— Environmental And Human Health Concerns



### 3-26 disc harges began , rapid and dramatic changes in the fish populations were observed [ Lemly, 1993]. By 1975, morphological abnormalities (e.g., partial fin loss, head deformities, cataracts) were reported for all 19 fish species monitored in the lake. Within two years following the release of ash pond effluent into the lake, several species experienced complete reproductive failure with only four species remaining by 1978 (i.e., four years after discharges began). Water samples collected in the lake reported elevated levels of arsenic, selenium, and zinc. Large predatory fish were some of the first species to die out completely, due to the lethal and sublethal effects of exposure to ash pond effluent. Because a top predator was gone, some fish that exhibited developmental abnormalities were able to survive, despite their otherwise high susceptibility to predation [Lemly, 1993]. The study eventually correlated the observed fish abnormalities with high selenium whole -body concentrations, and identified the planktonic community as the key source of selenium to the impacted fish. In 1985, the Belews Creek Steam

Station switched to disposing of the coal ash in a dry landfill and ended the ash pond discharges to the lake. In a 1997 study, Lemly determined that there was e vidence that the lake was recovering; however, even 11 years after the discharges ceased

, selenium levels in the sediments still posed a risk to wildlife that feed on benthic organisms. Lemly also observed that despite the reduction in the selenium concentration in fish ovaries, reproductive abnormalities remained persistent , highlighting the long ecological recovery time observed in the Belews Lake.

In addition to population density effects, communities in both field and experimental studies exposed to co mbustion wastewater have also experienced alterations in species diversity, which can further prolong ecosystem recovery [Benson and Birge, 1985; Guthrie and Cherry, 1976; Rowe et al., 2001; Specht et al., 1984] . In a study of fish populations in Martin La ke following a short eight-month period in which the lake received fly ash pond discharges, both planktivorous (i.e., diet primarily consists of plankton) and carnivorous (i.e., diet primarily consists of meat) fish populations were severe ly reduc ed [ Garre tt and Inman, 1984]. T hree years

after the effluent release was halted , planktivorous fish populations remained extremely low, while carnivorous fish populations had nearly recovered. Carnivorous fish have a more diverse diet than planktivorous fish and th erefore benefited from an increase in food availability as the aquatic system recovered; however, the size of carnivorous fish present in the lake suggested that surviving adults continued to have reproductive impairments [Garrett and Inman, 1984]. Sorensen (1988) documented that ecological impacts in the lake remained evident even up to eight years after the eight -month exposure to fly ash discharges, with sunfish populations continuing to exhibit tissue damage to the liver, kidneys, gills, and ovaries and impaired overall reproductive health.

3.4 D ISCHARGE TO 

### S ENSITIVE 

### E NVIRONMENTS



### The pollutant loadings and long ecological recovery times discussed in Section 3.3 are also of concern due the proximity of many steam electric power plants to sensitive environments where the characteristics of combustion wastewater may impair water quality (e.g., 303(d)- listed waters and waters with fish advisories) or pose a threat to thre atened and endangered species.Section 3

— Environmental And Human Health Concerns



### 3-27 EPA identified the number of surface waters that receive discharges of the evaluated waste streams and are located in close proximity to the following sensitive environments: 10

• 

### Impaired waters;

• 

### Fish consumption advisory waters; and

• 

### Threatened and endangered species habitats.

Table 3-10 summarizes the number and percentage of immediate receiving waters identified in each sensitive environment category.

Table 3-10. Number and Pe rcentage of Immediate Receiving Waters Identified as a Sensitive Environment

Sensitive Environment Number (Percentage) of Immediate Receiving Waters Identified a 

### Impaired water 162 (51%) Surface water impaired for a subset of pollutants associated

with the evaluated waste streams b 

### 80 (25%)

Fish consumption advisory water 189 (60%) Surface water with a fish consumption advisory for a subset of pollutants associated with the evaluated was te streams c 

### 119 (38%)

a – For the sensitive environment proximity analysis, EPA evaluated 317 immediate receiving water combinations that receive discharges of the evaluated waste streams [ERG, 2013e; ERG, 2013l]

. b

– Table B

- 1 in Appendix B contains a complete list of the impairment categories identified in EPA’s 303(d)

- listed waters and designates the subset of pollutants evaluated.

c – Table B

- 2 in Appendix B contains a complete list of the types of advisories identified under the sensitive

environmen t proximity analysis, including pollutants that are not associated with the evaluated waste streams.



### 3.4.1 Proximity to Impaired Waters

A surface water is classified as a 303(d) impaired water when pollutant concentrations exceed water quality standards and th e surface water can no longer meet its designated uses (e.g., drinking, recreation, and aquatic habitat). Based on that definition, half of the immediate receiving waters included in the EA are impaired waters. 11 

### EPA reviewed the identified 303(d) impairmen t categories and determined approximately 25 percent of the immediate receiving

water s are impaired for a pollutant associated with the evaluated waste streams. Table 3-11 presents the number and percentage of immediate receiving waters that are impaired for a pollutant associated with the evaluated waste streams. Figure 3-1

, Figure 3-2 , and Figure 3-3 illustrate the geographical location of plants that directly discharge combustion wastewater to a water classified as impaired by high concentrations of arsenic, mercury, selenium, metals (other than mercury ), and nutrients.

10 ERG memorandum Proximity Analysis Methodology (DCNS SE02151), describes the methodology used to evaluate the proximity of steam electric power plants to sensitive environments.

11 Table B

- 1 in Appendix B contains a complete list of the impairment categories identified under the sensitive environments proximity analysis, including pollutants that are not associated with the evaluated w aste streams.Section 3

— Environmental And Human Health Concerns



### 3-28 Table 3-11. Number and Percentage of Immediate Receiving Waters Classified as Impaired for a Pollutant Associated with the Evaluated Waste Streams

Pollutant Causing Impairment Number (Percentage) of Immediate Receiving Waters Identified a



### Arsenic 3 (1%)

Cadmium 5 (2%)

Chlorides 3 (1%)

Chromium b 

### 4 (1%)

Copper 7 (2%)

Lead 7 (2%)

Manganese 5 (2%)

Mercury 52 (16%)

Nutrients 30 (9%)

Phosphorus 16 (5%)

Selenium 3 (1%)

TDS 4 (1%)

Zinc 4 (1%)

a – For the impaired waters proximity analysis, EPA evaluated 317 immediate receiving water combinations that receive discharges of the evaluated waste streams [ERG, 2013e; ERG 2013l]

. b

– Impairment category is for total chromium. An impairment type is not designated specifically for chromium VI.



### Figure 3-1. Location of Plants that Directly Discharge Combustion Wastewater to a Surface Water Impaired due to Arsenic, Mercury, and SeleniumSection 3

— Environmental And Human Health Concerns



### 3-29 Figure 3 -2. Location of Plants that Directly Discharge Combustion Wastewater to a Surface Water Impaired due to Metals Other than Mercury

Figure 3 -3. Location of Plants that Directly Discharge Combustion Wastewater to a Surface Water Impaired due to NutrientsSection 3

— Environmental And Human Health Concerns



### 3-30 3.4.2 Proximity to Fish Consumption Advisory Waters

Fish consumption advisories are issued by states, territories, and authorized tribes when pollutant concentrations in fish tissue are considered unsafe for consumption [U.S. EPA, 2011e].

EPA determined that 60 percent of the immediate receiving water s included in the EA are under fish consumption advisories; however, only 38 percent of the immediate r eceiving waters are under an advisory for a pollutant associated with the evaluated waste streams. 12 

### Table 3-12

identifies the number of immediate rece iving water s with a fish consumption advisory for a pollutant associated with an evaluated waste stream. Figure 3-4 illustrates the geographical

locati on of plants that directly discharge combustion wastewater to surface waters with a fish consumption advisory for cadmium, lead, and mercury.

Table 3-12 . Number and Percentage of Immediate Receiving Water s Iss ued a Fish Consumption Advisory for a Pollutant Associated with the Evaluated Waste Streams

Advisory Type a 

### Number (Percentage) of Plant

Receiving Waters Identified b



### Cadmium 1 (<1%)

Lead 3 (1%) Mercury 118 (37%)

a – EPA did not identify any immediate receiving water s that were issued fish consumption advisories for arsenic

or selenium.

b

– For the sensitive environment proximity analysis, EPA evaluated 317 immediate receiving water combinations that receive discharges of the evaluated waste s treams [ERG, 2013e; ERG, 2013l]

.

12 Table B

- 2 in Appendix B contains a complete list of the types of advisories identified under the sensitive environment proximity analysis, including pollutants that are not associated with the evaluated waste streams.Section 3

— Environmental And Human Health Concerns



### 3-31 Figure 3 -4. Location of Plants that Directly Discharge to a Surface Water with a Fish Consumption Advisory for Cadmium, Lead, and Mercury

3.4.3 Proximity to Threatened and Endangered Species Habitats

Under the Endangered Species Act (ESA), endangered species are those in danger of extinction throughout all or a significant portion of its range. Threatened species are those species that are likely to become endangered within the foreseeable future. A species may be listed solely on the basis of their biological status and threats to their existence. The U.S. Fish and Wildlife Service (FWS) considers five factors for listing: 1) damage to, or destruction of, a species’ habitat; 2) overutilizatio n of the species for commercial, recreational, scientific, or education purposes; 3) disease or predation; 4) inadequacy of existing protection; and 5) other natural or manmade factors that affect the continued existence of the species.

EPA evaluated the extent to which the estimated range and critical habitats of currently listed threatened and endangered species, or those in consideration for listing under the ESA (as of January 23, 2012) overlaps with surface waters that receive discharges of the evalu ated waste streams. EPA identified surface waters estimated to exceed NRWQC for the protection of aquatic life under baseline conditions (see Section 5.3 ) as “affe cted areas” with the potential to harm threatened and endangered species. EPA determined that 224 threatened and endangered species habitats are located within an “affected” surface water under baseline conditions.

In addition, EPA assessed the vulnerabil ity of each species identified to changes in water quality and developed the following categories:

• 

### High vulnerability – species living in aquatic habi tats for several life history stages and/or species that obtain a majority of their food from aquatic so urces.Section 3

— Environmental And Human Health Concerns



### 3-32 • 

### Moderate vulnerability – species living in aquatic habitats for one life history stage and/or species that obtain some of their food from aquatic sources.

• 

### Low vulnerability – species whose habitats overlap bodies of water, but whose life history tra its and food sources are terrestrial.

EPA classified 52 percent of the species (127 of 224 species) with habitats located within an “affected” surface water as highly vulnerable to changes in water quality. For further details

on the threatened and endangered species analysis and results see the Benefits and Cost Analysis for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (DCN SE03172 ) (Benefits and Cost Analysis ).

3.4.4 Proximity to Drinking Water Resources

EPA also evaluated the potential for steam electric power plants to pose a threat to public sources of drinking water. Although many of the pollutants (e.g., selenium, mercury, arsenic, nitrates) in the evaluated waste streams wou ld likely be reduced to safe levels during drinking

water treatment, these pollutants could potentially impact the effectiveness of the treatment processes, which could increase public drinking water treatment costs. 13 

### EPA evaluated the proximity of steam e lectric power plants to the following sensitive environments for drinking

water resources:

• 

### Drinking water intakes

– drinking water sources that collect surface water through a public water system. Intakes are protected under the Safe Water Drinking Act (S DWA) of 1974 and its 1986 and 1996 amendments, which require delegated states and tribes to perform routine testing to ensure that they meet state drinking water

standards.

• 

### Public wells – drinking water sources that collect ground water through a public water system. Public wells are protected under the SDWA, which requires delegated states and tribes to perform routine testing to ensure that they meet state drinking

water standards.

• 

### Sole-source aquifers – drinking water sources that supply at least 50 pe rcent of the drinking water consumed in the area overlying the aquifer. These areas can have no reasonably available alternative drinking water source(s) if the aquifer were to

become contaminated.

• 

### Table 3-13 summarizes the number and percentages of plants included in the

national- scale proximity analysis that are located within 5 miles of the evaluated drinking water resources.

13 For more informatio n on drinking water treatment processes used to reduce or eliminate metals commonly

detected in the evaluated waste streams from steam electric power plants, see the ERG memorandum Drinking Water Treatment Technologies that Can Reduce Metal and Selenium Co ncentrations Associated with Discharges from Steam Electric Power Plants (DCN SE02154).Section 3

— Environmental And Human Health Concerns



### 3-33 Table 3-13. Comparison of Number and Percentage of Steam Electric Power Plants Located within 5 Miles of a Drinking Water Resource

Drinking Water Resource Number (Percentage) of Plants

Located within 5 Miles of a Drinking Water Resource a



### Intake 116 (37%)

Public well 268 (85%)

Sole

- source aquifer 15 (5%)

a – For the drinking water resource proximity analysis, EPA evaluated 317 immediate receiving water combinations that receive discharges of the evaluated waste streams [ERG, 2013e; ERG, 2013l]

.



### 3.5 D OCUMENTED 

### E NVIRONMENTAL 

### I MPACTS



### The documented environmental impacts from exposure to combustion wastewater indicate that the threat these wastes pose to huma n health and wildlife is a widespread problem that is not isolated to a few unique locations or circumstances. EPA identified over 130 steam electric power plants 14 

### causing environmental impacts to surface water and ground water environments following exposure to combustion wastewater , which are summarized in Table A

3 . Impacts identified in the literature include lethal and sublethal impacts on fish, impacts on the diversity and size of populations in the ecosystem, and impacts on drinking water quality.

Al though EPA did not find evidence of human health impacts, documented impacts of MCL

exceedances downstream of steam electric power plants and the issuance of fish advisories in waters that receive combustion wastewater indicate that there is a potential fo r human health impact . This section summar izes the documented surface water and ground water case studies and damage cases and discusses the potential for similar impacts to occur at other steam electric power plants.

14 For several damage cases, the specific plant associated with the site was not identified. EPA used information available in the literature and proximity of the plant to the damage case site to identify the plant. See footnotes i and j in Table A

- 3 for further details on EPA’s assumptions.Section 3

— Environmental And Human Health Concerns



### 3-34 3.5.1 Case Studies and Damage Cases Documenting Surface Water Impacts

EPA identified 132 case studies and damage cases 15 

### from 55 steam electric power plants 16 

### that document surface water impacts following exposure to combustion wastewater [AECOM, 2009; ASU, 2009; DRBC, 2006; EIP et al., 2010a and 2010b; ERG, 2012b; Gazette, 2011; MDNRE, 2010; Ruhl, 2012; U.S. EPA, 2007b; U.S. EPA, 2010e] . Surface water impacts include damage to fish populations (i.e., physiological and morphological abnormalities and various behavioral, reproductive, and devel opmental effects), decreased diversity in insect populations, and decline of aquatic macroinvertebrate population. Table 3-14 highlights several

case s tudy sites identified in the peer

- reviewed literature where negative surface water impacts from steam electric discharges have been studied. In most cases, negative impacts have been studied and documented in multiple articles and reports. The table also lists the

number of literature documents that discussed impacts at each site and summarizes these impacts. In addition to the literature case studies, EPA also identified damage cases in a separate review [U.S. EPA, 2012b; U.S. EPA, 2013e]. These are summa rized in Appendix A

in Tables A -6 and A-7, which summarize the damage cases from combustion residuals surface impoundments and landfills, respectively.

15 EPA defines “case study” and “damage case” as documented impacts to ground water and/or surface water from

combustion wastewater. A given steam electric power plant may be associated with multiple case studies and damage cases.

16 For several damage cases, the specific plant associated with the site was not identified. EPA used information available in the literature and proximity of the plant to the damage case site to identify the plant. See footnotes j and

k in Table A

- 3 for fur ther details on EPA’s assumptions. Some wastewater surface impoundments are located in, or near, large river floodplains. Failure of the embankments of surface impoundments can release catastrophic amounts of pollutants into surrounding

ecosy s tems.3-35 Section 3

— Environmental And Human Health Concerns



### Table 3-14. Summary of Select Documented Surface Water Impact Case Studies

Site Name and

Location Number of Documents

that Discuss Surface Water Impacts at the Site Case Study Overview

Savannah River Site, SC 23 The Savannah River Site, which is owned by the Department of Energy (DOE), is divided into several areas, based on production, land use, and other related characteristics. The D

- area, a site utilized by numerous ecologists to study the impacts of coal

- fired power plant waste , houses a coal

- fired power plant that discharges

ash into a series of pond s and a swamp that ultimately drains into the Savannah River. Numerous studies observed organisms within these habitats accumulated high concentrations of trace elements in their ti ssues and exhibited various physiological, behavioral, and developmental effects.

Belews Lake, NC 13 In 1970, Duke Power Company constructed Belews Lake as a cooling water reservoir to support the Belews Creek Steam Station. Almost immediately after ash pond effluent began discharging in to the lake, fish populations experienced morphological changes, repr oductive failure, and eventually death. In 1985, Belews Creek Steam Station converted to a dry

- ash transport system, ending the ash pond discharges to the lake. However, even 11 years after the discharges ceased, reproductive abnormalities persisted in the fish populations.

Martin Lake, TX 8 Martin Lake is a cooling water reservoir that also receives combustion wastewater discharges. In 1978 and 1979, a series of major fish kills occurred due to the elevated concentrations of selenium in the water and fis h tissue. Numerous studies conducted throughout the 1980s documented histopathological and reproductive damage in the fish populations inhabiting the lake. In addition, the studies determined that the overall health of the aquatic populations near the disc harge site remained adversely affected by the selenium pollution, despite the reduction in the annual discharge of selenium. In 1992, a fish consumption advisory was issued for the

lake due to discharges from the steam electric plant

. Hyco Reservoir,

NC 8 Hyco Reservoir is a large cooling water reservoir that received effluent from a power plant’s fly ash ponds. In 1981, a large

- scale fish kill occurred in the reservoir, prompting numerous scientific studies to examine the extent and cause of the environmental damage. Multiple studies detected selenium concentrations in the water and tissue of fish inhabiting the reservoir, while other trace elements were within normal concentration ranges.

The results of these studies indicate that the selenium concentrations induced lethal effects in the fish populations.

Glen Lyn, VA 5 Glen Lyn Plant discharged fly ash sluice water from an ash pond into Adair Run, a tributary of the New River. A 1984 study reported that the local insect diversity and density remained essentially the same upstream (reference site) and downstream of the ash pond when the pond was not close to capacity. However, as the settling pond reached its capacity, the insect density and diversity declined downstream. After closure of the pond, it took up to 10 months for the insect populations to recover [Specht et al., 1984].3-36 Section 3

— Environmental And Human Health Concerns



### Table 3-14. Summary of Select Documented Surface Water Impact Case Studies

Site Name and

Location Number of Documents

that Discuss Surface Water Impacts at the Site Case Study Overview

Gibson Lake, IN 4 Gibson Lake is a man

- made, shallow impoundment that receives ash pond effluent from Gibson Generating Station. Starting in 1986, least terns, an endangered species of migratory birds, began using the dike in Gibson Lake as a nesting ground for breeding. To protect the birds from potential toxic exposure, the plant began a cooperative program with the Indiana Department of Natural Resources to protect the nest ing birds by creating a nearby alternative habitat, known as Cane Ridge Wildlife Management Area (WMA) , which received water pumped from Gibson Lake. In April 2007, Duke Energy closed access to the lake for recreational fishing due

to elevated selenium lev els. A year later, the U.S. Fish and Wildlife Service (USFWS) became concerned about selenium levels in the water and fish in the Cane Ridge WMA . The USFWS stopped the flow of water from Gibson Lake into Cane Ridge, discourage d least terns from using the refuge, remove d the contaminated fish, and plowed Cane Ridge to redistribute and bury the selenium in the soil. Subsequently, t he USFWS stopped the fl ow of water from Gibson Lake into Cane Ridge and piped water from Wabash River instead

. Cane Ridge was restocked with fish to lure back migratory birds. As of June 2009

, avocets, dunlins, black terns, Forster's terns, Caspian terns

, and 50 endangered least terns have returned to Cane Ridge.

Rocky Run Creek, WI 5 Rocky Run Creek receives effluent from Columbia Generating Station’s ash pond. After the generating station began operation in 1975, the aquatic macroinvertebrate populations declined in the area. Two studies conducted at this site concluded that populatio n density decreased, not because of death due to coal ash toxicity, but because the aquatic macroinvertebrate populations avoided the area due to sublethal alterations in

the creek.

McCoy Branch,

TN 3 In 1986, coal ash slurry discharges from DOE’s Chestnut Ridge Y

- 12 power plant into McCoy Branch were found to contain elevated concentrations of trace elements, which violated the Tennessee Water Quality Act. A 1992 report conducted by DOE documented bioaccumulati on of contaminants in fish tissues, decreased diversity in benthic macroinvertebrate communities, and increased fish mortality and abnormalities at the site
[ DOE, 1992 ]

. Welsh Reservoir,

TX 2 Welsh Reservoir serves as a cooling water reservoir for Welsh Power Plant. From 1986 to 1989, the Texas Park and Wildlife Department ( TPWD ) reported increases in the selenium concentrations of the fish inhabiting the receiving water. As a result, the Texas Department of Health ( TDH ) issued a fish consumption advisory for the reservoir because of the potential health impact due to the levels of selenium in fish. In 1998, TDH collected 20 fish for reevaluation and observed an average selenium concentration in the fish above the reported national averages. Therefore, the Agency for Toxic Substances and Disease Registry ( ATSDR ) concluded in a report that there was no clear indication of an overall change in selenium fish tissue

co ncentrations over the 12 years [ ATSDR, 1998b ].3-37 Section 3

— Environmental And Human Health Concerns



### Table 3-14. Summary of Select Documented Surface Water Impact Case Studies

Site Name and

Location Number of Documents

that Discuss Surface Water Impacts at the Site Case Study Overview

Brandy Branch Reservoir, TX 1 Brandy Branch Reservoir serves as a cooling water reservoir for Pirk e y Power Plant. From 1986 to 1989, the TPWD reported increases in the selenium concentrations of the fish inhabiting the receiving water. As a result, the Texas Department of Health (TDH) issued a fish consumption advisory for the reservoir, because of the potential health impact due to the levels of selenium in fish. Since the fish kills in the 1980s , Southwestern Electric Power Company has worked cooperatively to monitor fish tissue selenium concentrations, which have decreased since the late 1980s [ATSDR, 1998a]

.

Mountain Island Lake, NC 5 Duke Energy's Riverbend Plant discharges ash pond effluent into Mountain Island Lake, which supplies drinking water to 700,000 people. The county staff ha s detected arsenic and zinc concentrations above state

standards in an area near the ash pond discharge pipe ( Charlotte Observer, 2010). The plant continues to extensively monitor metal concentrations in Mountain Island Lake surrounding the point of discharge [NCDENR, 2011].

TVA’s Kingston Fossil Plant, TN 6 On December 22, 2008, the retaining wall of a coal ash pond at TVA’s Kingston Fossil Plant broke and released billions of gallons of coal ash slurry into the Emory, Clinch, and Tennessee Rivers. The only published studies conducted at this site are of init ial assessments of the potential impacts to the aquatic life and human health. The primary concern addressed in the available literature is the high concentration of mercury detected in the river sediments, which may pose a long

- term threat to the ecology of these rivers.

Source: ERG, 2013b.Section 3

- Environmental And Human Health Concerns



### 3-38 3.5.2 Case Stud ies and Damage Cases Documenting Ground Water Impacts

Pollutants in combustion residuals can leach into ground water from surface impoundments and landfills at the site . Older surface impoundments and landfills are of particular concern because they were often built with out liners and leachate collection systems

. Liners are typically made of synthetic material, asphalt, clay, or a composite of materials (e.g., synthetic and clay) and are designed to collect leachate and prevent ground water contamination. Combustion residuals held in unlined surface impoundments can enter the subsurface and

contaminate ground water. Unlined landfills, used for the dry disposal of combustion residuals, are also subject to leaching as precipitation flows through the residuals pile and dissolves pollutants into the leachate, which can eventually migrate into ground water. New facilities are increasingly installing liners in surface impoundments and landfills; but pollutants can also enter the ground water when liners fail or when a disposal site is situated such that natural ground water fluctuations come into contact with the disposed waste. Furthermore, state regulation on leachate collection systems and impermeable liners is not uniform [ EPRI, 1997; 65 FR 32214– 32237, 2000].

EPA identified 123 case studies and damage cases 17 

### from 118 steam electric power plants 18 

### that document impacts to ground water quality caused by leachate from combustion residuals surface impoundments and landfills [AECOM, 2009; ASU, 2009; DRBC, 2006; EIP et al., 2010a and 2010b; ERG, 2012b; Gazette, 2011; MDNRE, 2010; MACo, 2007; U.S. EPA, 2007b; U.S. EPA, 2010e]. 19 

### The majority of the case studies and damage cases reported ground water pollutant levels in on

- site wells above regulatory levels; however , only a portion of the

cases indicated off -site contamination. Documented impacts to off- site ground water resources may be lower due to long migration times within the subsurface until the leachate reaches a known monitoring point [NRC, 2006]. Further, the limited number of case studies documenting

off

- site contamination might reflect the less extensive monitoring of off

- site ground water wells for evidence of impacts from leachate, which suggests off- site impacts may be underrepresented

in the documented ground water impacts [ Cherry, 2000 ].

In surface impoundments, combustion residuals are in constant contact with water, allowing toxic metals to leach into and eventual ly contaminat e ground water. From an environmental impacts perspective, combustion residuals surface impoundment s are generally considered less desirable than landfills for disposal because they provide constant saturated or nearly saturated conditions and a relatively large hydraulic driving force to move leachate into

the subsurface [T heis and Gardner, 1990]. The primary impacts observed from surface impoundments include MCL exceedances of arsenic, selenium, cadmium, lead, boron, and

17 EPA defines “case study” and “damage case” as documented impacts to ground water and/or surface water from combustion wastewater. A given steam electric power plant may be associated with multiple case studies and damag e cases.

18 For several damage cases, the specific plant associated with the site was not identified. EPA used information available in the literature and proximity of the plant to the damage case site to identify the plant. See footnotes j and

k in Table A

- 3 for further details on EPA’s assumptions.

19 In December 2011, EIP released a report titled Risky Business: Coal Ash Threatens America’s Groundwater

Resources at 19 More Sites (DCN SE1985) identifying 19 additional ground water damage cases. These allege d damage cases have not been reviewed or confirmed by EPA.Section 3

- Environmental And Human Health Concerns



### 3-39 manganese in off- site ground water and drinking water wells. Table A -4 in Appendix A summarizes documented ground water damage cases from combustion residuals surface impoundments [EIP et al., 2010a and 2010b; U.S. EPA, 2007b].

Although more desirable than surface impoundments, landfills pose their own ground

water contamination risks. If the landfills are n ot properly lined, the pollutants in combustion

residuals can leach into the soil during precipitation. In areas with acid rain, the precipitation’s low pH can accelerate the leaching of contaminants into ground water. In addition, heavy precipitation can not only accelerate leaching, but also carry pollutants in stormwater runoff, potentially contaminating ground water or surface water resources [ Andersen and Madsen, 1983]. The primary impacts observed from landfills include MCL exceedances of arsenic,

sel enium, boron, manganese, and sulfates in off-site ground water and drinking water wells

Table A -5 in Appendix A summarizes documented ground water damage cases from combustion

residuals landfills [EIP et al., 2010a and 2010b; MDNRE, 2010 ; U.S. EPA, 2007b].

A concern associated with ground water contamination from combustion residuals surface impoundment s and landfills is the potential for leachate to impact private drinking water resources. Numerous damage cases documented pollutant levels exceeding MCLs; however, many times the damage case documentation did not specify if the well with the MCL exceedance was a monitoring well or a drinking water well. However, the fact that many sites reported MCL

exceedance s in ground water testing suggests that potenti al impacts to drinking water resources

are a realistic concern. The following three damage cases are documented instances where leachate contamination impacted private drinking water wells.

Constellation Ash Disposal at Waugh Chapel and Turner Pits

– Ann e Arundel County, Maryland

For over a decade, Constellation Energy Group (Constellation) supplied fly ash for structural fill at the B.B.S.S. Inc. (BBSS) sand and gravel mines in Anne Arundel County, Maryland. Fly ash from Constellation’s Brandon Shores and Wagner plants was used to reclaim portions of BBSS’s Turner Pit starting in 1995 and the Waugh Chapel Pit starting in 2000. In the fall of 2006, Anne Arundel County Health Department officials documented concentrations of sulfate and metals (i.e., antim ony, beryllium, cadmium, manganese, and nickel) exceeding the state’s screening criteria for potable aquifers in residential wells located downgradient from Waugh Chapel and Turner Pits [MDNR, 2007].

An independent study of the contamination confirmed tha t the elevated concentrations of sulfate and metals observed in the wells directly resulted from precipitation infiltrating the fly ash deposited in the BBSS sand and gravel mines [MDNR, 2007]. In October 2007, the Maryland Department of the Environment (M DE ) fined Constellation and BBSS $1 million for the ground water contamination and required the companies to restore the local aquifer water quality [MDE, 2008]. In addition, Anne Arundel homeowners impacted by the contamination

filed a class action lawsui t against Constellation and were awarded a $45 million settlement . The

settlement required Constellation to pay the costs for converting 84 homes from well water to public water; cease future deliveries of new coal ash to the quarry; and to establish trust funds to compensate impacted property owners, enhance the neighborhood, and remediate and restore a former quarry site [Schultz, 2008].Section 3

- Environmental And Human Health Concerns



### 3-40 Virginia Power Yorktown Power Station Chisman Creek Disposal Site

– Virginia

Between 1957 and 1974, Virginia Power ’s Yo rktown Power Station deposited fly ash in sand and gravel pits at the Chisman Creek Disposal Site. In 1974, the Yorktown Power Station discontinued disposal at the site because the plant began burning oil.

In 1980, the water in a nearby shallow residential well turned green. Investigations in response to the drinking water discoloration determined that the residential well exceeded the primary MCL for selenium and found heavy metal contamination in the ground water around the fly ash disposal areas, in on- site surface impoundments, and in the sediments of Chisman Creek

and its tributaries.

In September 1983, EPA added the site to the National Priorities List under the Comprehensive Environmental Response, Compensation, and Liabilities Act (CERCLA). Cleanup began in late 1983 and included extending public water to 55 homes with contaminated well water, capping the disposal pits, collecting ground water and leachate for treatment, lowering the water table beneath the pits, and post- clos ure monitoring.

Ground Water Violations Near North Carolina Power Plants With Ash Ponds – North

Carolina

The North Carolina Department of Environment and Natural Resources reported ground

water contamination near coal ash ponds at all 14 of the state’s coal-fired power plants. Duke Energy and Progress Energy each own seven of the plants and perform ground water monitoring as required by the state. M anganese and lead concentrations exceeded state ground water

standards at all 14 locations and TDS and chromium exceeded state standards at seven locations

. Boron levels at six of the facilities exceeded state ground water standards, and some facilities

had e levated levels of arsenic, selenium, thalliu m, antimony, chlorides , and nickel. The state and plants have not identified the source of the contamination but noted that the exceedances occurred at newly located wells. D rilling the wells may have affect ed the concentration o f naturally occurring eleme nts such as lead and manganese [Ballard, 2012]. 20



### 3.5.3 Potential for Impacts to Occur in Other Locations

Key environmental characteristics that contributed to the impacts documented in

Sections 3.5.1 and 3.5.2 , such as chronic exposure to large pollutant loadings, plants discharging to waters with long residence times, and no liner s in surface impoundment s or landfills

, are

common at steam electric power plants. This suggests that the impacts documented above

indicate the greater potential threat combustion wastewater discharges pose to the environment. Although substantial events s uch as fish kills are well -documented, the extent to which more subtle damages, such as histopathological changes, morphological deformities, and damage to reproductive success , occur elsewhere is not known due to the limited extent of monitoring

programs.

20 EPA notes that the impacts repor ted at North Carolina plants have not been documented in a peer

- reviewed literature source; however, the information shows that elevated levels of metal contamination can occur near ash ponds.Section 3

- Environmental And Human Health Concerns



### 3-41 The majority of the documented environmental impacts discussed above occurred following discharges of combustion wastewater under normal operations. Although the actual amounts of pollutant loadings discharged may vary among steam electric power plants, most of the documented case studies do not indicate that the pollutant loadings associated with the impact s are unusual for steam electric power plants. This suggests that chronic exposure to typical combustion wastewater pollutant loadings can impact the environment at other sites not

documented in the literature.

As discussed in Section 3.3 , the residence time of combustion wastewater pollutants in

surface water is a major factor in determining the impact to the environment and the length of the recovery time. Many documented case study sites are lentic water bodies such as lakes (i.e., still waters) where pollutants can reside for long periods of time. These type s of receiving waters are at particular risk to impacts from combustion wastewater discharges. S team electric power plants

that discharge to a pond, lake, or reservoir may experience similar environmental effects as those observed in the documented case studies from analogous aquatic systems [U.S. EPA, 201 3a]

.

According to the documented case studies, lack of a liner in surface impoundments and landfills is a significant factor in determining the extent of combustion wastewater impacts to ground water. Bas ed on responses to the Steam Electric Survey, EPA identified 511 active surface impoundment s and 153 active landfills containing combustion wastewater at steam electric power plants that currently do not have liners and may be contributing to similar ground

water impacts documented in the case studies [U.S. EPA, 201 3a]

.Section 4

— Exposure Pathways



### 4-1 

# SECTION 4
E XPOSURE PATHWAYS

An exposure pathway is defined as the route a pollutant takes from its source (e.g., combustion residuals surface impoundments) to its endpoint (e.g., a surface water), and how receptors (e.g., fish, wildlife, or people) can come into cont act with it. Exposure pathways are typically described in terms of five components:

• 

### Source of contamination.

• 

### Environmental pathway—the environmental medium or transport mechanism that moves the pollutant away from the source through the environment (e.g., discharges to surface waters).

• 

### Point of exposure— the place (e.g., private drinking water well) where receptors (e.g., people) come into contact with a pollutant from the source of contamination.

• 

### Route of exposure—the way (e.g., ingestion, skin contact) receptors come into contact with the pollutant.

• 

### Receptor population—the aquatic life, wildlife, or people exposed to the pollutant.

The exposure pathway plays an important role in determining the potential effects of

combustion wastewater on the environment . For example, the physical and chemical

characteristics of receiving waters can affect the fate and transport of pollutants from combustion

residuals surface impoundments to the environment and ultimately impact how the pollutants interact with the biolog ical community.

The U.S. Environmental Protection Agency (EPA) identified three primar y exposure pathways of concern for combustion wastewater entering the environment: (1) discharges and leachate entering surface waters, (2) leaching to ground water, and (3) direct contact with

combustion wastewater stored in surface impoundment s. This sec tion describes the factors that control the magnitude of combustion wastewater pollutant impacts to water quality, wildlife, and human health and presents EPA’s methodology for evaluating

the national effect of combustion wastewater pollutants on the environment. Table 4-1 presents the environmental pathways, routes of exposure, and environmental concerns identified during the literature review and the type of analysis conducted to determine the impacts under baseline conditions and regulatory options. Pollutants from combustion wastewater stored in surface impoundments can reach receptor populations (such as wildlife or people) through various exposure pathways.Section 4

— Exposure Pathways



### 4-2 Table 4-1. Combustion Wastewater Environmental Pathways and Routes of Exposure Evaluated in the EA

Environmental Pathway Route of Exposure Environmental Concern Analysis to Determine Environmental Impact

Combustion wastewater discharges to surface

waters Direct contact with surface

water Changes in surface water

contamination levels Water Quality Impacts (Quantitative)

Section 4.1.2

Direct contact with sediment Changes in sediment

contamination levels Wildlife Impacts (Quantitative)

Section 4.1.2 Consumption of

contaminated fish B ioaccumulation of

contaminants in piscivorous

wildlife

B ioaccumulation of

contaminants in fish consumed by humans Human Health Impacts (Quantitative)

Section 4.1.2

Ingestion of contaminated

surface water Toxic effects on fish and aquatic life Wildlife Impacts (Qualitative)

Section s 4.1

Combustion residuals surface impoundment or landfill leachate infiltration to nearby

surface waters Direct contact with surface

water or sediment Changes in surface water

and sediment contamination

levels Surface Water Impacts (Qualitative)

Section 4.1

Combustion residuals surface impoundment or landfill leachate entering ground water Ingestion of water Changes in ground water quality Ground Water Quality Impacts (Qualitative)

Section 4.2 Contaminated private drinking water wells

Combustion residuals surface impoundment Direct contact or ingestion

of surface water Toxic effects on wildlife Attractive Nuisances (Qualitative)

Section 4.3 B ioaccumulation of

contaminants in wildlife



### 4.1 C OMBUSTION 

### W ASTEWATER 

### D ISCHARGE AND 

### L EACHATE 

### E NTERING 

### S URFACE


### W ATERS



### Steam electric power plants commonly discharge combustion wastewater directly to surface waters following storage and treatment (e.g., particulate settling) in surface impoundment s. At some steam electric power plants, wastewater and leachate collected from combustion residuals landfills and/or surface impoundment s may be treated using advanced wastewater treatment systems that employ chemical precipitation or biological treatment prior to discharge back into a surface impoundment or to receiving water. In addition to effluent discharges, leachate from combustion residuals landfills and surface impoundment s can migrate through the soil and into the receiving water. Further details on leachate are included in the discussion of the ground water environmental pathway in Section 4.2

.Section 4

— Exposure Pathways



### 4-3 4.1.1 Factors Controlling Environmental Impacts in Surface Waters

One o f the primary factors controlling the environmental impact of combustion wastewater on surface waters is the residence time of the pollutants once they enter an aquatic system. Residence times are often determined by the flow rate of the receiving water an d type of ecosystem it supports. The potential for pollutant retention in lentic aquatic systems (i.e., still or slow-moving water, such as lakes or ponds) and the creation of hot spots in lotic aquatic systems (i.e., flowing water, such as streams and riv ers) are of particular concern when bioaccumulative pollutants are present. Many of the pollutants in combustion wastewater discharges bioaccumulate, which can further complicate estimates of potential impacts in surface waters because the pollutants can a ffect higher trophic levels, local terrestrial environments, and transient species, in addition to the aquatic organisms directly exposed to the wastewater.

Based on results from EPA’s 2010 Questionnaire for the Steam Electric Power Generating Effluent Gu ideline (Steam Electric Survey)

, 21 

### EPA determined that 18 percent of aquatic environments that receive combustion wastewater discharges are lentic systems such as lakes, ponds, reservoirs, and estuaries ( Table 4-2 ). The majority of ecological studies on the impact of combustion wastewater in aquatic environments have focused on lentic systems [Rowe et al., 2002]. In lentic aquatic systems, the hydraulic residence time, or the amount of time it takes for the water in the aquatic system to be replaced by inflowing streams or precipitation is relatively long, allowing pollutants to build up over time and making lentic systems more vulnerable to impacts from combustion wastewater. In addition, aquatic organisms are limited in their ability to avoid areas of high pollutant concentrations and are restricted to the food supply available only within the water body.

Table 4-2. Final Outfall Receiving Water Types for Steam Electric Power Plants Within Scope of the Loadings Analysis

Receiving Water Type Number (Percentage) of Immediate Receiving Waters

River/stream 261 (82%)

Lake/pond 28 (9%)

Reservoir 8 (3%)

Great Lakes 14 (4%)

Estuary 6 (2%)

Total Receiving Waters 317 (100%)

Source: ERG, 2013l.



### Based on results from EPA’s Steam Electric Survey, EPA determined that 82 percent of aquatic environments that receive combustion wastewater discharges are lotic systems such as rivers and streams [U.S. EPA, 2013a ]. Lotic systems dilute discharges more quickly than lentic systems. The moving water in lotic systems also provides a transport mechanism to disperse pollutants greater distances from the power plant, and enables aquatic organisms to move away

21 Results presented in this report are based on plant responses to the Questionnaire for the Ste am Electric Power Generating Effluent Guidelines , which represent 2009 data.Section 4

— Exposure Pathways



### 4-4 from the areas of combustion wastewater contamination [Rowe et al., 2002]. Although the discharge of combustion wastewater into a lotic system can distribute pollutants across a greater spatial area, changes in flow velocity may result in the concentration of pollutants at a single location further downstream [Rowe et al., 2002]. For example, combustion wastewater discharged to a river may encounter depositional areas of slower moving water downstream where pollutants would fall out of suspension and concentrate in a limited area. These pockets of higher pollutant concentrations, or hot spots, could be vulnerable to continued resuspension as stream velocities are affected by rainfall events, resulting in the pollutants being available to aquatic organisms over much longer periods of time [Lemly, 1997; Rowe et al., 2002].

4.1.2 Assessment of the Surface Water Exposure Pathway

EPA developed a receiving water model to quantify the environmental impacts to surface waters, wildli fe, and human health from the waste streams evaluated for the regulatory options. As part of this national assessment, EPA determined impacts in the immediate surface water where steam electric industry discharges occur, between one and file miles from the outfall depending on the stream reach. 22 

### As part of the benefits and cost analysis, EPA also evaluated surface water concentrations downstream from steam electric discharges using EPA’s Risk

Screening Environmental Indicators (RSEI) model; see the Benefits and Cost Analysis for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (DCN SE03172) (Benefits and Cost Analysis). The framework focused on four key areas of impacts :

• 

### Impacts to aquat ic life based on changes in water quality;

• 

### Impacts to aquatic life based on changes in sediment quality;

• 

### Impacts to wildlife from consumption of contaminated fish; and

• 

### Impacts to human health from consumption of contaminated fish.

EPA considered the type o f receiving waters commonly impacted by steam electric power plants and the pollutants typically found in the evaluated waste streams in selecting the appropriate methodologies for the quantitative analysis. The receiving water model quantifies the environmental risks within 1) rivers/streams and 2) lakes/ponds (including reservoirs) based on the determination that almost 95 percent of the final outfall receiving water designations fell within these categories. 23



### A key factor in determining the pollutants to include in the receiving water model was the dilution of discharges either by commingling cooling water with the evaluated waste streams prior to discharge or by the receiving water flows following discharge. F or example, EPA

22 See the ERG memorandum Water Quality Model: Plant and Receiving Water Characteristics (DCN SE01955) for details on the immediate discharge zone and length of stream reach repres ented.

23 The specific hydrodynamics and scale of the analysis required to appropriately model and quantify receiving water concentrations in the Great Lakes and estuary systems are more appropriately handled separately on a case study basis. EPA evaluated the impacts to the Great Lakes and Chesapeake Bay systems from a total mass loadings perspective in a separate qualitative analysis, discussed in Section 3.2. See the ERG memorandum Site

- Specific Estuary Dilution Analysis (DCN SE02152) for details on EPA’s initial screening analysis of the modeled receiving water concentrations in the Great Lakes and estuary systems in comparison to water quality benchmarks.Section 4

— Exposure Pathways



### 4-5 determined that 58 percent of rivers and streams included in the model analysis had an average annual flow greater than 1,000 cubic feet per second. Due to the potential for dilution prior to discharge and in the receiving water, EPA focuse d the quantitative analysis on pollutants where the total mass loadings and not the concentration are critical factors in determining the potential for environmental impact. For the evaluated waste streams, nutrients and bioaccumulative metals represent th e two primary pollutant categories considered for the receiving water model

.

Large amounts of nutrients entering a surface water can present an environmental
concern. However, nutrient-related environmental problems (e.g., eutrophication) tend to be sites pecific depending on environmental factors (e.g., water

- body temperature, the limiting nutrient in the system, algal species in the water body, availability of oxygen in the water) and are better evaluated on a case study basis. Therefore, EPA did not quan tify surface water nutrient impacts

for the receiving water quantitative analysis. 24 

### EPA estimated total nitrogen and total phosphorus concentrations using dilution equations as input values to analyze benefits related to improvements in water quality. EPA us ed the SPARROW (SPAtially Referenced Regressions On Watershed attributes) model to provide baseline concentrations, as well as concentrations under each regulatory option. EPA used these c oncentrations to develop sub-indi ces for a water quality index (WQ I), a value that translates water quality measurements, gathered for multiple

parameters that represent various aspects of water quality, into a single numerical indicator. Total nitrogen and total phosphorous are only two of the sub-indices included in th e WQI ; t he others are dissolved oxygen, biochemical oxygen demand, fecal coliform, total suspended solids (TSS), and heavy metals. EPA then used the WQI as a basis for calculating a willingness to pay for an increase in water quality as a result of the dif ferent regulatory options. See the Benefits and Cost Analysis for further details on the analysis and the results.

EPA’s receiving water model includes three interrelated models:

• 

### W ater quality model

— calculates immediate receiving water specific metal concentrations in the water column and sediment and evaluates the impacts that receiving concentrations pose to aquatic life and human health.

• 

### W ildlife model

— evaluates the impact that sediment concentrations pose to aquatic life, calculates the metal concentra tions in exposed fish populations, and evaluates the potential adverse effects to minks and eagles from consumption of fish.

• 

### Human health model— calculates non -cancer and cancer risks to human populations from the consumption of fish.

The water quality model uses plant-specific input data (i.e., plant- specific pollutant loadings and cooling water flow rate ), 25 

### surface

- water

- specific characteristic data (e.g., receiving water flow rate, lake volume), and default assumption values to quantify the environmental impacts of the evaluated waste streams to surface waters. It calculates pollutant concentrations in

24 EPA qualitatively evaluated the potential environmental impact of nutrients within the context of the total mass nutrient loadings entering the Great Lakes and Chesapeake Bay from steam electric power plants (see Section 3.2).

25 EPA calculated pollutant loadings for the evaluated waste streams and excluded any pollutants discharged with

other wastewat ers (e.g., coal pile runoff). EPA incorporated cooling water flow rates into the water quality model on

a site

- by

- site basis. EPA assumed no pollutant loadings were associated with cooling water discharges to surface

waters.Section 4

— Exposure Pathways



### 4-6 the surface water and sediment. These concentrations are inputs for the wildlife model, which calculates the bioaccumulation of pollutants in fish tissue an d determines impacts to wildlife. The fish tissue concentration calculated in the wildlife model is an input to the human health model. This section provides overviews of each model. Appendices C through E describe the model calculations, inputs, and assumptions in further detail. The Appendices also describe the limitations and assumptions of the models. Figure 4 -1 provides an overview of the model inputs and the connections among the three models to support EPA’s national- scale modeling

framework.

Figure 4 -1. Overview of Receiving Water Model

Water Quality Model

As discussed above, EPA focused the quantitative analysis on the mass of pollutants discharged to determin e the potential for environmental impact. EPA selected the steady

- state equilibrium-partitioning model described in EPA’s Methodology for Assessing He alth Risks Associated with Indirect Exposure to Combustor Emissions (EPA 600-R-98-137) for the water quality model. This selection was based on three factors: the model’s ability to represent metals in the aquatic environment, model complexity judged to be appropriate for a national

- scale

evaluation

, 26 

### and level of previous Agency and external peer reviews performed on the modeling methodology. An equilibrium-partitioning model assumes that dissolved and sorbed metals in a receiving water will quickly attain equilibrium in the immediate vicinity of the discharge point

26 For a national

- scale environm ental assessment of nearly 300 receiving waters, data limitations inhibit the feasibility of using more complex fate and transport receiving water models (dynamic or hydrodynamic) to estimate

surface water concentrations.Section 4

— Exposure Pathways



### 4-7 by assuming that sorption reactions in the surface water are fast relative to transport or dispersion of the metal outside the immediate area. The model also assumes that the equilibrium state f or each metal can be represented by a partition coefficient that divides the total mass of a metal in the water body into four compartments:

• 

### Constituents dissolved in the water column;

• 

### Constituents sorbed onto suspended solids in the water column;

• 

### Constitu ents sorbed onto sediments at the bottom of the water body; and

• 

### Constituents dissolved in pore water in the sediments at the bottom of the water body.

Table 4-3 list s the metals commonly found in the evaluated waste streams with known environmental impacts ( see Section 3.1

, Table 3-1 ). EPA selected a subset of the se metals for the water quality model based on a combination of the following criteria:

• 

### The metal is known to be present in the evaluated waste streams.

• 

### Scientific literature documents elevated levels observed in surface waters or wildlife from exposure to combustion wastewater.

• 

### Partition coefficient data were avail able for the water quality model.

• 

### Benchmarks are available to determine impact risks to wildlife or human health.

For the receiving water q uality analysis, EPA modeled 10 of the metals shown in Table

4-3 : arsenic, cadmium, chromium VI, copper, lead, mercury, nickel, selenium, thallium, and zinc. These metals include the six metals with the highest toxic weighting factors (TWFs) (see

Table 3-2 )— arsenic , cadmium, lead, mercury, selenium, and thallium; along with discharges of four additional metals known to bioaccumulate in aquatic organisms: chromium VI, copper, nickel, and zinc. Although EPA identified manganese and boron in the top three pollutants with the highest toxic weighted pound equivalents (TWPEs) for baseline pollutant loadings (see Table

3-2 ), EPA did not include these metals in the model due to lack of partition coefficient data and limited threshold criteria data for comparison. EPA identified total dissolved solids (TDS) and chlorides as the pollutants with the largest loadings und er baseline conditions (see Table 3-2 ); however, EPA did not include these pollutants in the receiving water model for several reasons. TDS from the evaluated waste streams consists largely of dissolved metals that are already captured in the receiving water model. Therefore, estimates of potential environmental impacts from TDS would double-count many of the environmental impacts and potential improvements

assessed. Ch lorides lack partition coefficient data and have limited numeric threshold criteria data for comparison.4-8 Section 4

— Exposure Pathways



### Table 4-3 . Metals Considered for Analysis in the Receiving Water Model

Pollutant Literature

Review a 

### Partition

Coefficient b 

### NRWQC c 

### Maximum

Contaminant Level (MCL) Wildlife

Benchmark d 

### Human Health

Benchmark e 

### Included in Modeling Analysis f



### Aluminum  

Arsenic g 

###       

Boron  

Cadmium       

Chromium h 

###       
Copper       

Iron  

Lead     
Manganese  
Mercury i 

###       

Nickel      

Selenium j 

###       

Thallium     

Vanadium   

Zinc     

a – Literature review identified documented cases of elevated levels in surface waters or wildlife near steam electric power plants [ERG, 2013b]

.
b

– Partition coefficients for modeling analysis identified in U.S. EPA

, 1999

, and U.S. EPA

, 2005 a

.

c – Aquatic life or human health N ational R ecommended W ater Q uality C riteria (NRWQC) available at http://water.epa.gov/scitech/swguidance/standards/current/index.cfm.

d

– No e ffect h azard c oncentration (NEHC) identified in USGS

, 2008

, for mink s and bald eagles.

e – Reference d ose (RfD) identified in EPA’s Integrated Risk Information System (IRIS) for a ll pollutants except copper and thallium ( available at http://www.epa.gov/iris/ ); RfD for copper is the intermediate oral minimal risk level ( MRL ) [ ATSDR

, 2010 a]; and RfD for thallium is the value for thallium chloride provided in U.S. EPA

, 2010 a . Cancer slope factor for arsenic identified in EPA’s IRIS database [ 2011 ].

f

– Metal is included in the quantitative modeling analysis discussed in this section.

g – Arsenic exists in two primary forms: arsenic III and arsenic V. Che ck m arks were included for total arsenic, arsenic III, and arsenic V.

h

– Chromium exists in two primary forms: chromium III and chromium VI. Check marks were included for total chromium and chromium VI

.
i

– Check marks were included for mercury and methylmer cury.
j

– Selenium exists in two primary forms: selenate and selenite. Check marks were included for total selenium, selenate, and sele nite.Section 4

— Exposure Pathways



### 4-9 EPA developed the water quality model in Microsoft AccessTM using the equilibriumpartition equations presented in Appendix C. The water quality model is a mathematical model used to represent the partitioning of pollutants through the surface water after the combustion wastewater has been discharged. The model output provides site- specific pollutant concentrations in the water column (total, dissolved, and suspended) and sediment for all steam electric power plants located across the United States that discharge to a river or stream or to a lake, pond, or reservoir. Figure 4-2 depicts the pollutant concentrations calculated in the water quality model. EPA implemented this modeling approach through the following steps:

1. Characterize the immediate receiving water characteristics (e.g., depth of water column, depth of water body, receiving water width, and flow independent mixing value) using site

- specific inputs. See the ERG mem orandum Water Quality Model: Plant and Receiving Water Characteristics (DCN SE01955 ).

2. Using the immediate receiving water characteristics, determine the fraction of pollutant in the benthic sediment and in the water column and determine fraction of pollutant in the water column that is dissolved.

3. Using the immediate receiving water charact eristics and assumed input values, calculate the water column volatilization rate constant (for volatile metals only – i.e., mercury).

4. Calculate the water concentration dissipation rate (zero for nonvolatile metals).

5. Based on site- specific pollutant loadin gs, cooling water flow rates (for a subset of plants), and immediate receiving water characteristics, calculate the total pollutant concentrations (e.g., total arsenic) in the immediate receiving water, including the

concentration in the water column and in the benthic sediment. The model also calculates the concentration of dissolved pollutant in the water column. Section 10 of

the Technical Development Document for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Gen erating Point Source Category (TDD) (DCN SE01964) details the pollutant loadings methodology; the

ERG memorandum Water Quality Model: Plant and Receiving Water Characteristics (DCN SE01955 ) describes the use of cooling water flow rates. Note that the metal loadings included in the model are not representative of the total metal load ings from steam electric power plants ; several waste streams were not evaluated (e.g., stormwater runoff, metal cleaning wastes, coal pile runoff).

6. Quantify the number of sites that exceed the National Recommended Water Quality Criteria (NRWQC) and drinking water maximum contaminant levels (MCLs) to
evaluate the potential exposure of ecological receptors (i.e., aquatic biota) and human

receptors to toxic pollutants in the environ ment from the evaluated waste streams.Section 4

— Exposure Pathways



### 4-10 Source: U.S. EPA, 1998b



### Figure 4-2. Water Quality Model: Pollutant Fate in the Water Body

As an indicator of potential impacts , EPA compared b ase line and regulatory option

immediate receiving water concentrations to the following NRWQC:

• 

### Freshwater acute and chronic aquatic life NRWQC;

• 

### Human health NRWQC for the consumption of water and organisms ; and

• 

### Human health NRWQC for the consumption of organis ms

.

EPA also compared immediate receiving water concentrations to drinking water MCLs.

EPA identified immediate receiving waters that exceeded a NRWQC or MCL as an indication of the degradation of the overall water quality following exposure to the evaluat ed waste streams.

Section 5.3 summarizes the NRWQC and MCL exceedances under baseline pollutant loadin gs. Section 6.2 presents the percent reduction in number of immediate receiving waters that potentially impact water quality under the regulatory options.

As with any modeling, EPA recognizes that model limitations exist and certain assumptions need to be made. EPA used average annual pollutant loadings and effluent flow rates, which do not take into account temporal variability (e.g., seasonal differences, storm flows, low flow events, catastrophic events). Model- specific lim itations and assumptions are included in Appendix C of this report. The results of the water quality model are included in Section 5 and

Section 6 of this report.

Wildlife Model

As shown in Figure 4-1 , the wildlife model builds off the water quality model by using the calculated immediate receiving water and sediment concentrations to calculate metal Mass Load Discharged

from Evaluated Waste
Streams Volatilization

Bottom (Benthic)

Sediment Water Column

Degradation

Burial 

### C

wc 

### C

sw 

### C dw



### C bs



### C wTot 

### = C

wc 

### + C bs Cooling Water

from Plant (if applicable) Pollutant concentration (C) is calculated by the water quality model using average annual flow rate of the receiving water (and cooling water flow rate where applicable)

Equilibrium Reaction C

wc – Concentration

in the water column

C dw – Concentration

that is dissolved in
the water

C

sw – Concentration that is suspended in

the water

C wTot – Concentration in the water body

C bs – Concentration

sorbed to bottom (or benthic) sedimentSection 4

— Exposure Pathways



### 4-11 concentrations in fish populations exposed to the evaluated waste streams and to assess the potential to impact wildlife for the following categories :

• 

### Impact to aquatic organisms from contact with sediment contaminated by the

evaluated waste streams by quantifying the number of sites with potential exposure of ecological receptors (i.e., sediment biota) to the pollutant in the environment ; a nd

• 

### Impact to piscivorous wildlife (i.e., wildlife that habitually feeds on fish) from consuming fish impacted by the evaluated waste streams by quantifying the number

of sites with potential exposure of ecological receptors (i.e., piscivorous wildlife) to the pollutant in the environment.

EPA developed the wildlife model in Microsoft Access TM 

### to calculate metal concentrations in fish populations exposed to the evaluated waste streams and estimate daily

contaminant dose for wildlife receptors (e.g., minks and eagles) using equations presented in Appendix D. The wildlife model derives an indicator of potential impacts to wildlife by comparing the concentration in the contaminated media (i.e., water, sediment, or fish) to

concentrations known to have impact (i.e., benchmark). Benchmarks are pollutant- and endpointspecific and sometimes are species -specific. Benchmarks are an expression of the concentration level in contaminated media that is protective against a specific endpoint (e.g., mortality). Endpoints frequently reflected in benchmark values include sublethal effects such as reduced reproduction, neurological effects, and lethal effects. In the wildlife model, the potential impact

to wildlife is expressed in terms of a hazard quotient (HQ). An HQ is the ratio of concentration

in contaminated media to a concentration benchmark. An HQ of 1 is defined as the highest pollutant concentration at which no adverse health effects are likely to occur . Therefore, a n HQ greater than 1 indicates a potential impact to wildlife for the endpoint associated with the benchmark value used in the HQ analysis. For example, if the HQ for mercury for eagles is greater than one, then there is a potential threat for their reproductive health to be impacted.

EPA implemented the wildlife modeling approach through the following steps:

1. Calculate the pollutant concentration in fish for trophic level three (T3) or trophic level four (T4), 27 

### using the calculated pollutant concentration in the water column and the bioconcentration factor ( BCF). For mercury, calculate the concentration of methylmercury in the fish. See Appendix D.

2. Calculate the HQ s for ecological receptors ( sediment biota, mink, and eagle).

3. Compare the baseline and regulatory option results : number of sites with potential exposure of ecological receptors to concentrations with potential impacts

.

Adverse Effects to Aquatic Organisms from Contact with Sediment

. Th e w ildlife

m odel calculates HQs for benthic organisms exposed to metal sediment concentrations

calcul ated in the water quality model. EPA used benchmarks provided in the National Oceanic and Atmospheric Administration (NOAA) 2008 Screening Quick Reference Tables (SQuiRTs),

27 T3 fish (e.g., carp, smelt, perch, catfish, sucker, bullhead, sauger) are those that consume invertebrates and plankton, while T4 fish (e.g., salmon, trout, walleye, bass) are those that consume other fish.Section 4

— Exposure Pathways



### 4-12 referred to as the chemical stressor concentration limit (CSCL), for the sediment b iota HQ

calculations. The CSCL is a chemical

- specific media concentration that is protective of ecological receptors of concern. The CSCL benchmark is species -specific, but can be used to represent a community of organisms, such as amphibians or fish. Usua lly the most sensitive (or lowest) CSCL for a species is used to represent the community. Table D -1 presents the CSCL benchmarks used for sediment exposure analysis. The results of this analysis for baseline pollutant loadings are discussed in Section 5.3.2 of this report.

Assessment of Pollutant Bioconcentration in Fish. EPA calculated fish tissue

concentrations based on 1) total water column concentrations (i.e., dissolved plus sorbed) calculated in the water quality model and 2) trophic- level

- specific BCFs. BCFs are based on the compilation of field and laboratory study results to develop a single factor or ratio for estimating the amount of pollutant transferred into fish tissue at a given trophic level (i.e., rank in the food chain) based on the pollutant concentration in the water body. EPA estimated fish tissue concentrations in milligrams per kilogram (mg/kg) for T3 and T4 fish to account for the variability in fish likely consumed by both wildlife and human receptors included in the receiving water model

.

Although using the total water body concentration in the BCF analysis may overestimate

the level of metals in the fish, it provides for a more environmental ly protective estimate of risk

in the subsequent human health model because it assumes that all metals within the water body (both dissolved and sorbed) are bioavailable to the exposed fish. The exception to this methodology is mercury, where EPA based the fish tissue concentration calculation on the dissolved concentration of methylmercury in the water body [U.S. EPA, 2005b]. Appendix D presents the BCFs and model equations for the analysis of metal bioconcentration in fish tissue

for T3 and T4 fish.

Impa ct to Piscivorous Wildlife

. EPA based the piscivorous wildlife impact analysis on the methodology outlined in the 2008 U.S. Geological Survey (USGS) study Environmental Contaminants in Freshwater Fish and Their Risk to Piscivorous Wildlife Based on a Nationa l Monitoring Program . The study examined the impacts to minks and eagles from eating contaminated fish. Minks and eagles are commonly used in ecological risk assessments as indicator species for potential impacts to fish

- eating mammals and birds in areas contaminated

with bioaccumulative pollutants [USGS, 2008]. Minks and eagles are appropriate receptors for the steam electric wildlife impact analysis because their habitats span most of the country and their diet largely consists of adult fish from the tw o trophic levels (i.e., T3 and T4 fish) calculated in the wildlife model. According to the literature [U.S. EPA, 1998a], minks consume mostly T3 fish, while eagles consume mostly T4 fish. EPA evaluated the potential adverse effects to minks and eagles for nine metals commonly found in the waste streams of interest: arsenic, cadmium, chromium, 28 

### copper, mercury, 29 

### nickel, lead, selenium, and zinc. The USGS method [USGS, 2008] is a wildlife impact analysis using NOAELs (no-observed- adverse

- effect levels), which were derived from adult dietary exposure or tissue concentration studies based

28 Because there is no benchmark for chromium VI, EPA used the total chromium benc hmark, which may

underestimate the risk to wildlife.

29 Because there is no benchmark for methyl mercury, EPA used the total mercury benchmark, which may

underestimate the risk to wildlife.Section 4

— Exposure Pathways



### 4-13 primarily on reproductive endpoints. The study calculated a benchmark called the no effect hazard concentration (NEHC), which is based on the NOAEL, the food consumption rate, and/or the biomagnification factor of each receptor. The report states that piscivorous wildlife may be at risk for reduced reproduction rates if the measured metal concentration in fish exceeds the NEHC. Therefore, EPA calculated an HQ for minks using the mink- specific NEHC values from the USGS study for comparison with the T3 fish tissue concentrations. EPA a lso calculated an HQ for eagles using the eagle -specific NEHC values from the USGS study for comparison with the T4 fish tissue concentration. In the piscivorous wildlife analysis, an HQ greater than one indicates that piscivorous mammals or birds exposed to fish in the immediate receiving water of interest are at risk for reduced reproduction rates or other health effects.

Table D -3 presents the NEHC values used to evaluate potential adverse effects to wildlife; the text of Appendix D presents the equations used to compare model outputs to benchmarks (NEHCs), along with model-specific limitations and assumptions. The results of the

wildlife model are included in Section 5 and Section 6 of this report.

Human Health Model

As shown in Figure 4-1 , the human health model builds off the wildlife model, using the

calculated T3 and T4 fish tissue concentrations. Its purpose is to evaluate the cancer risk and potential to cause non- cancer health effects from the consumption of fish within the following age and consumption categories:

• 

### C hild recreational fishers ;

• 

### Child subsistence fishers;

• 

### Adult recreational fishers ; and

• 

### Adult subsistence fishers.

EPA developed the human health model in Micro soft Access TM 

### to estimate the daily contaminant (i.e., metal) doses for human receptors as a result of eating T3 and T4 contaminated fish. EPA used a mathematical model to estimate the potential threats to human receptors from pollutant exposure. EPA estim ated the average concentration of metals in a fish filet consumed by humans based on a consumption diet of 36 percent T3 and 64 percent T4 fish (see Appendix E). The human health model then calculates the daily dose of metals from fish consumption for each human cohort (i.e., recreational and subsistence fishers, child or adult) included in the analysis. 30 

### EPA varied the fish consumption rate and body weight of each cohort based on age to determine a daily metal dose for each human cohort evaluated. Table E -2 presents the human cohorts included in the human health model and the corresponding fish consumption rates and body weights used in the model. EPA implemented the human health modeling approach through the following steps:

1. Calculate the pollutant concen tration in a fish filet.

30 The child cohort age ranges correspond to the ranges provided in the 2008 Child

- Specific Exposure Factors

Handbook ( EPA

- 600 -R- 06

- 096F ) for body weights.Section 4

— Exposure Pathways



### 4-14 2. Calculate daily dose of pollutant from fish consumption by each receptor cohort (used for comparison to reference dose [RfD] values).

3. Calculate the lifetime average daily dose (LADD) for carcinogenic pollutants only, by each recept or cohort (used to determine cancer risk).

4. Calculate the lifetime excess cancer risk (LECR) for carcinogenic pollutants only, by each receptor cohort, using the LADD.

5. Compare the exposure doses of human receptor cohort s to appropriate benchmarks (RfD and selected cancer benchmark: 1

- in -a- million).

6. Compare the baseline and regulatory option results: reduction in the number of immediate receiving waters with exposure doses from the consumption of fish that pose a potential threat to human receptors.

Non

- Can cer Threat to Human Rece ptors

. EPA evaluated the non- cancer threat ( e.g., reproductive or neurological impacts) to each human cohort by calculating an HQ based on the comparison of the metal-specific daily dose values for fish consumption to RfD s. EPA evaluated

non- cancer risks for the following metals: inorganic a rsenic

, 31 

### cadmium, chromium VI, copper, methylmercury, n ickel, selenium, thallium, and z inc . Table E -3 in Appendix E presents the RfD

values used in the non- cancer threat analysis. RfD values are a n expression of the consumption dose that is protective against a specific endpoint. Endpoints frequently reflected in RfDs include various immunological, reproductive, neurological, and other non- cancer effects. In the human health model, the potential im pact to humans is expressed in terms of an HQ. An HQ of 1 is

defined as the highest consumption dose at which no adverse health effects are likely to occur

. Therefore, an HQ greater than 1 indicates a potential threat to humans for the endpoint associated with the RfD value used in the HQ analysis. For example, an HQ greater than 1 for selenium

indicates that the exposure dose from fish consumption has the potential to cause non- cancer health effect, such as selenium -induced liver dysfunction or selenosis ( hair or nail loss, morphological changes of the nails, etc.) [U.S. EPA, 2011c].

Cancer Risk to Human Rec e ptors

. Arsenic is the only pollutant 32 

### included in the receiving water model for which EPA has derived a cancer slope factor for ingestion exposures.

The human health model calculates the LADD for each receptor cohort based on an exposure duration (i.e., length of time a receptor is in contact with the carcinogen) averaged over a lifetime

31 For this analysis, EPA decided to use only the concentration of inorganic arsenic for the human health impact assessment. Based on the literature review, arsenic in f ish is mostly in the organic form and is not considered harmful. The wildlife model calculates a total arsenic fish tissue concentration. To convert this number to inorganic arsenic, EPA assumed that 4 percent of the total arsenic is inorganic based on EPA ’s 1997 document, Arsenic and Fish Consumption (EPA

- 822 -R- 97

- 003). The 1997 document reported that the inorganic arsenic concentration in fish is between 0.4 and 4 percent of the total arsenic accumulating in fish [U.S. EPA, 1997b].

32 Although EPA has det ermined that lead and lead compounds can be “reasonably anticipated to be human carcinogens,” no numeric value has been determined to quantify the cancer risk. As stated on the IRIS website, “quantifying lead’s cancer risk involves many uncertainties, some of which may be unique to lead. Age, health, nutritional state, body burden, and exposure duration influence the absorption, release, and excretion of lead. In addition, current knowledge of lead pharmacokinetics indicates that an estimate derived by stan dard procedures would not truly describe the potential risk. Thus, the Carcinogen Assessment Group recommends that a numerical estimate not be used.” (see http://www.epa.gov/iris/subst/0277.htm#reforal)Section 4

— Exposure Pathways



### 4-15 (i.e., 70 years). For this analysis, EPA assumed the exposure duration to be equal to the number of years represented by each cohort. The use of these exposure durations is appropriate for screening

- level estimates of cancer risk and to compare changes between baseline and regulatory options. 33 

### The model then multiplies the LADD by the cancer slope factor to calculate the LECR from arsenic. LECR is an estimate of the increase in cancer risk resulting from an exp osure (i.e., consumption of contaminated fish). EPA used the benchmark value for evaluating cancer risk of one in 1,000,000 people. Therefore, a calculated LECR greater than 1 × 10 -6 

### indicates carcinogenic human health impacts from the consumption of fish exposed to discharges of

evaluated waste streams.

4.2 L EACHING TO 

### G ROUND 

### W ATER



### Combustion residual landfills and surface impoundments can impact local ground water through leaching. Once in ground water, pollutants can migrate from the site and contaminate public or private drinking water

wells and surface waters [NRC, 2006]. The fate

of combustion residuals pollutants in ground water is controlled by many biological and geochemical (e.g., adsorption, desorption, and precipitation reactions with aquifer materials) processes that can vary over large spatial and temporal scales [NRC, 2006]. This section describes the pollutant concentrations, chemical

characteristics (e.g., solubility, leachability, persistence, and mobility) and fate and transport

processes that influence the potential impact of leachate from combustion residuals landfills and surface impoundments on the environment.

4.2.1 Factors Controlling Environmental Impacts to Ground Water

Environmental impacts to ground water are determined by the pollutant concentrations in the leachate and the rate of pollutant transport in the ground water. The pollutant concentrations

in the l eachate depend on factors including characteristics of the combustion residuals, site conditions (e.g., rainfall amount and pH of the pore water in the surface impoundment or landfill), and combustion residuals residence time in the surface impoundment or landfill. 34 

### The rate of pollutant transport in ground water depends on factors such as the biogeochemical characteristics of the subsurface (e.g., soil pH and oxidation-reduction potentials), local rates of ground water recharge, and unsaturated and saturat ed ground water flow velocities.

33 For a complete assessment of risk to an individual, EPA recommends that risks should be calculated by integrating exposures throughout all life stages (i.e., adding multiple cohort risks from screening analysis). The exposure duration may be equal to the length of time a person lives in an area [U.S. EPA, 2011b].

34 Leaching experiments indicate that the chemistry of leachates are based on both the chemical composition of the waste and other factors such as site conditions [Thorneloe et al., 2010]. Thorneloe [2010] specifically looked at fly

ash and bottom a sh waste from coal

- fired power plants. Most surface impoundments are unlined, allowing pollutants to infiltrate into ground water and eventually

into surface waters.Section 4

— Exposure Pathways



### 4-16 Pollutant Concentrations in Leachate

Combustion residuals characteristics include the mineralogy of the waste (e.g., lime, gypsum, iron, and aluminum oxide content) and pollutant solubility in the pore water. The mobility of metals may be altered due to changes in pH, carbon and chloride content, and interaction with other wastes from steam electric power plants [ Thorne loe, 2010 ]. The waste mineralogy can vary based on the chemical composition in the fuel source (e.g., the specific coal seam and geographic location of the mine) and operational characteristics at the plant. Many laboratory investigations have examined the solubility characteristics of various pollutants associated with fly ash [Prasad, 1996; Thorne loe, 2010 ]. The r esults of these investigations largely depend on multiple factors, and they tend to be more applicable qualitatively rather than quantitatively e.g., results from investigations can be used to determine the likelihood of a pollutant to dissolve in the leachate, but not the amount). Concentrations of inorganic pollutants derived from calcium, sodium, magnesium, potassium, iron, sulfur, and carbon are relatively high in aqueous solution of fly ash, because of their high total concentrations in the ash [ Prasad et al., 1996].

The pH of the pore water is a dominant factor in the leaching of pollutants from surface impoundments and landfills. Because most metals in combustion residuals exhibit weak acid or weak base behavior in aqueous solution, the pore water pH strongly influences the concentration of metal in the leachate. Steam electric power plants generate combustion residuals in high

temperature processes, and many acidic species (e.g., carbon dioxide, hydrogen sulfide, hydrochloric acid) are volatili zed prior to waste collection. Therefore, combustion residuals would be expected to yield an alkaline reaction in water; this is the case, but acidic reactions have also been observed [Theis et al., 1990]. Acidic pore water allows metals from the combustion residuals to remain in solution, increasing their mobility and the potential for ground water contamination. From a study of three power plants in Turkey, the results indicated that combustion residuals in the deeper layers of landfills and on the bottoms of the surface impoundments may continue to leach if the pH value drops in the surrounding environment [Baba and Kaya, 2004]. 35 

### Table 4-4

, Table 4-5

, and Table 4-6 present data collected by EPA’s Steam Electric Survey showing metal pollutant concentrations in the leachate for acidic , neutral,

and basic conditions.

35 This conclusion was based on a comparison of ash extraction procedures used. The study examined how the concentration of trace elements in the ash can vary based on the procedure used, comparing the EPA

- developed EP (extraction procedure) and its replacement method, TCLP (toxicity characteristic leaching procedure), and the ASTM (American Society for Testing and Materials) Method D

- 3987. A comparison of the results revealed that the ASTM procedure indicated much lower dissolved metal concentrations than the EP and TCLP procedures. These results indicate that pH is an important parameter affecting the leaching rate of metals from ash deposits. The lower pH values in the EP and TCLP methods increase the leaching rate of inorganic constituents of fly ash and bottom ash [Fleming et al., 1996].Section 4

— Exposure Pathways



### 4-17 Table 4-4. Metal Concentrations in Leachate Under Acidic Conditions (pH of 1.0 to 6.5)

Pollutant Minimum

Concentration

in Leachate (mg/L) Maximum

Concentration

in Leachate (mg/L) MCL (mg/L) Number of Samples Exceeding MCL (Total Number of Samples) Percentage of Samples Exceeding

MCL

Arsenic 1.00 x 10 - 3 0.301 0.01 15 (21) 62%

Boron 0.137 55.1 7 a 3 (21) 14%

Cadmium 3.07 x 10 - 5 1.87 x 10 - 2 0.005 6 (21) 29%

Chromium 1.00 x 10 - 4 1.68 x 10 - 2 0.1 0 (21) 0%
Copper 1.60 x 10 - 4 0.110 1.3 0 (21) 0%

Lead 5.00 x 10 - 6 1.62 x 10 - 2 0.015 1 (21) 5%
Manganese 3.75 x 10 - 2 86.8 0.05 b 20 (21) 95%
Mercury 2.00 x 10 - 7 7.51 x 10 - 2 0.002 1 (21) 5%

Nickel 3.92 x 10 - 3 1.26 No MCL NC (21) NC

Selenium 1.00 x 10 - 4 0.143 0.05 3 (21) 14%

Thallium 2.10 x 10 - 5 1.74 x 10 - 2 0.002 11 (21) 52%

Zinc 5.00 x 10 - 3 3.32 5 b 0 (21) 0%

Source: ERG, 2013g

. Acronyms: mg/L (milligrams per l iter); MCL ( Maximum C ontaminant L evel ); NC (n ot c alculated; no MCL for comparison ).

Note: Data are for untreated leachate at steam electric landfills and surface impoundment s.

a – The drinking water equivalent level, used for noncarcinogenic endpoints, is listed rather than the MCL.

b – MCL is a secondary (nonenforceable) standard.



### Table 4-5. Metal Concentrations in Leachate Under Neutral Conditions (pH of 6.5 to 7.5)

Pollutant Minimum

Concentration

in Leachate (mg/L) Maximum

Concentration

in Leachate (mg/L) MCL (mg/L) Number of Samples Exceeding MCL (Total Number of Samples) Percentage of Samples Exceeding MCL

Arsenic 6.00 x 10 - 5 0.202 0.01 19 (64) 30%

Boron 7.36 x 10 - 4 236 7 a 20 (64) 31%

Cadmium 2.00 x 10 - 5 1.28 x 10 - 2 0.005 2 (63) 3%

Chromium 4.00 x 10 - 5 2.72 x 10 - 2 0.1 0 (64) 0%
Copper 1.30 x 10 - 4 1.50 x 10 - 2 1.3 0 (64) 0%

Lead 1.00 x 10 - 5 2.50 x 10 - 3 0.015 0 (62) 0%
Manganese 2.00 x 10 - 4 8.64 0.05 b 52 (64) 81%
Mercury 1.50 x 10 - 7 0.190 0.002 10 (64) 16%

Nickel 9.00 x 10 - 5 0.162 No MCL NC (64) NC

Selenium 7.00 x 10 - 5 2.03 0.05 11 (64) 17%

Thallium 2.00 x 10 - 5 7.00 x 10 - 3 0.002 6 (62) 10%

Zinc 9.00 x 10 - 4 3.95 5 b 0 (63) 0%

Source: ERG, 2013g

. Acronyms: mg/L (milligrams per l iter); MCL ( Maximum C ontaminant L evel ); NC ( Not C alculated; no MCL for comparison ).

Note: Data are for untreated leachate at steam electric landfills and surface impoundment s.

a – The drinking water equivalent level, used for noncarcinogenic endpoints, is listed rather than the MCL.

b – MCL is a secondary (nonenforceable) standard.Section 4

— Exposure Pathways



### 4-18 Table 4-6. Metal Concentrations in Leachate Under Bas ic Conditions (pH of 7.5 to 14)

Pollutant Minimum

Concentration

in Leachate (mg/L) Maximum

Concentration

in Leachate (mg/L) MCL (mg/L) Number of Samples Exceeding MCL (Total Number of Samples) Percentage of Samples Exceeding MCL

Arsenic 6.00 x 10 - 5 0.25 0.01 64 (90) 71%

Boron 2.88 x 10 - 3 93.2 7 a 28 (91) 31%

Cadmium 1.00 x 10 - 5 0.39 0.005 26 (90) 29%

Chromium 1.00 x 10 - 4 2.2 0.1 16 (90) 18%
Copper 5.00 x 10 - 5 4.40 x 10 - 2 1.3 0 (91) 0%

Lead 9.00 x 10 - 6 0.49 0.015 2 (86) 2%
Manganese 2.00 x 10 - 4 4.37 0.05 b 48 (89) 54%
Mercury 2.00 x 10 - 7 6.90 x 10 - 2 0.002 7 (89) 8%

Nickel 9.00 x 10 - 5 7.94 x 10 - 2 No MCL NC (87) NC

Selenium 7.00 x 10 - 5 0.425 0.05 28 (90) 31%

Thallium 2.00 x 10 - 5 5.00 x 10 - 2 0.002 12 (86) 14%

Zinc 1.00 x 10 - 4 7.73 x 10 - 2 5 b 0 (86) 0%

Source: ERG, 2013g

. Acronyms: mg/L (milligrams per l iter); MCL ( Maximum C ontaminant L evel ); NC ( Not C alculated; no MCL for comparison ).

Note: Data are for untreated leachate at steam electric landfills and surface impoundment s.

a – The drinking water equivalent level, used for noncarcinogenic endpoints, is listed rather than the MCL.

b – MCL is a secondary (nonenforceable) standard.



### As Table 4-4

, Table 4-5 , and Table 4-6 show, acidic conditions can lead to higher

conc entrations in the leachate for the following pollutants in combustion wastewater

— arsenic, copper, manganese, nickel, and zinc. The solubility of most trace metals (the notable exceptions being arsenic and selenium) tend s to decrease with increased pH (i.e. , alkaline conditions). Chromium was the only metal with a concentration range that skewed higher at basic conditions. Arsenic, which had a higher concentration range at acidic conditions, exceeded its MCL in both acidic and basic leachate (due to its high er solubility in alkaline conditions). Similarly, manganese exceeded its secondary MCL under all pH conditions. Selenium had varying concentrations under all pH conditions, but exceeded its MCL more frequently under basic conditions. Overall, results are a s expected based on the literature data – more leaching (i.e., higher concentration) of metals in acidic conditions.

In addition to the pH of the pore water, amounts of precipitation can affect pollutant concentrations in the leachate. At landfills (dry disposal sites), rainfall and frozen precipitation infiltrates through the waste, dissolving pollutants that can then leach from the landfill. Landfills in drier climates will tend to generate less leachate than landfills in wetter climates.

The last factor affecting pollutant concentrations in the leachate is the combustion residuals residence time in the surface impoundment or landfill. In a study of metals (calcium, copper, iron, lead, magnesium, manganese, potassium, sodium, and zinc) leaching from fly ash and bottom ash, all pollutants exhibited a decrease in concentration with time of leaching, except for calcium, which released at a constant rate [Kopsick and Angino, 1981]. The most commonly

noted leachate release curve is an initial flush curve. For th is type of curve, the highestSection 4

— Exposure Pathways



### 4-19 concentrations of metals are released as the leachate initially forms, with rapidly decreasing concentrations over time. Therefore, active surface impoundments receiving fresh combustion residuals will produce a leachate with elevated concentrations of metals that have a greater potential to contaminate drinking water sources and surface waters. Most inactive surface impoundments where pollutants have initially already leached from the combustion residuals should produce a leachate with decreasing concentrations of metals [Kopsick and Angino, 1981].

Thorneloe et al. [2010] studied the leaching behavior of coal combustion residuals in landfills, performing tests using a range of pH conditions and liquid

- solid ratios expected during management via landfills or beneficial use. Leachate concentrations for

most metals were highly variable over a range

of coal types, plant configurations, and

combustion residuals types (i.e., fly ash or flue gas desulfurization [FGD] gypsum). The study showed significantly different leaching results (l iquid- solid partitionin g [equilibrium] as a function of pH ) for similar combustion residuals types and plants. The v ariability in metal leaching results was several orders of magnitude higher than the variability of the pollutant concentrations in the combustion residuals; this indicates that the pollutant concentrations alone cannot predict the leaching of metals, as noted above. Table 4-7 presents pollutant concentrations in combustion residuals samples across a pH range of 5.4 to 12.4 and the range of pollutant concentrations in the leachate. The table also includes indicator values for each pollutant: toxicity characteristic (TC) values for Resource Conservation and Recovery Act (RCRA) ha zardous waste regulatory determination and drinking water MCLs for leachate concentrations. As the table shows, the leachate pollutant concentrations for fly ash and FGD gypsum exceed both the MCLs and TC values for RCRA hazardous waste determinations for nine metals: antimony, arsenic, barium (fly ash only), boron, cadmium, chromium, molybdenum, selenium, and thallium.

Transporting Pollutants in the Ground W ater

Predicting the transport of combustion residuals pollutants in ground water can be challenging due to the wide range of biogeochemical characteristics that can exist between sites and within a given site. Pollutant transport times can vary, and combustion residuals pollutants can take many years to reach local drinking water wells and surface waters [NRC, 2006]. For example, in the damage case at the Virginia Power Yorktown Power Station Chisman Creek Dispolar Site in Virginia, fly ash had been disposed of in abandoned sand and gravel pits at the site for almost 20 years, from 1957 to 1974. However, ground water contamination was not discovered until 1980, when nearby shallow residential wells became contaminated with selenium above the primary MCL and vanadium and sulfate above the secondary MCL. After further investigation, the ground water around the fly ash disposal areas was found to have elevated levels of many types of heavy metals [U.S. EPA, 2007b]. The pH level of pore water in surface impoundments can strongly influence the concentration of pollutants in leachate from impoundments to ground water.Section 4

— Exposure Pathways



### 4-20 Table 4-7. Range of Fly Ash and FGD Total Content and Leaching Test Results (Initial Screening Concentrations) for Trace Metals

Pollutant Indicator Values Range of Combustion

Residuals Content Range of Leaching Test

Results

TC Value for

Hazardous Waste Designation (μg/L) Drinking

Water

MCL (μg/L) Fly Ash (mg/kg) FGD Gypsum (mg/kg) Fly Ash (μg/L) FGD Gypsum

(μg/L)
Antimony

— 6 3.0

– 14 0.14

– 8.2 <0.3

– 11,000 <0.3

– 330

Arsenic 5,000 10 17

– 510 0.95

– 10 0.32

– 18,000 0.32

– 1,200

Barium 100,000 2,000 50

– 7,000 2.4

– 67 50

– 670,000 30

– 560

Boron

— 7,000 a NA NA 210

– 270,000 12

– 270,000

Cadmium 1,000 5 0.3

– 1.8 0.11

– 0.61 <0.1

– 320 <0.2

– 240

Chromium 5,000 100 66

– 210 1.2

– 20 <0.3

– 7,300 <0.3

– 240
Mercury 200 2 0.1

– 1.5 0.01

– 3.1 <0.01

– 0.50 < 0.01

– 0.66
Molybdenum

— 200 a 6.9

– 77 1.1

– 12 <0.5

– 130,000 0.36

– 1,900

Selenium 1,000 50 1.1

– 210 2.3

– 46 5.7

– 29,000 3.6

– 16,000

Thallium

— 2 0.72

– 13 0.24

– 2.3 <0.3

– 790 <0.3

– 1,100

Source: Thorn e loe et al

. , 2010.

Acronyms: MCL (m aximum c ontaminant l evel ); mg/kg (m illigrams per k ilogram ); TC (Toxicity Characteristics); μg/L (microgram s per l iter); NA ( Not A vailable ).

a – The drinking water equivalent level, used for noncarcinogenic endpoints, is listed rather than the MCL

.



### Natural mechanisms, such as soil buffering capacity, attenuation of trace metals in certain soil types, amount of organic matter, and low soil permeability, can limit the transport of combustion residuals pollutants in the subsurface environment. The mobility of metals in the subsurface strongly depends on soil- specific characteristics. Soil can exert a buffering influence over the leachate by raising or lowering the pH. The solubility of most trace metals (the notable exceptions being arsenic and selenium) tend t o decrease with increased pH (i.e., alkaline conditions). In general, trace metals are less mobile in alkaline soils because the metals will precipitate and/or adsorb onto hydrous iron and aluminum oxides. Theis and Richter [1979] attempted to assess the f actors influencing the attenuation of trace metals in the soil/ground water environment. Results show that the major solubility control for cadmium, nickel, and zinc is adsorption by iron and manganese oxides while chromium, copper, and lead are controlled by precipitation. In some cases, particles in leachate may seal a surface impoundment or landfill, reducing the amount of leachate entering the ground water. Simsiman et al. [1987] and Kopsick and Angino [1981] both reported evidence of some sealing and reduction in permeability of combustion residuals surface impoundments leading to reduced seepage.

4.2.2 Assessment of the Ground Water Exposure Pathway

The EA focused on the discharges of toxic, bioaccumulative metals to surface waters

from the evaluated waste streams . The EA did not quantify the environmental and human health impacts resulting from pollutants leaching into the ground water from coal combustion residualsSection 4

— Exposure Pathways



### 4-21 (CCRs ) surface impoundments and landfills. 36 

### Additionally, the water quality model used for

th is EA did not consider pollutant loadings to surface waters resulting from the migration of CCR pollutants through the soil and into surface waters, even though this may be occurring at many of the plants. As shown in Tables A-4 and A-5 in Appendix A, seve ral damage case studies have documented impacts to surface waters due to ground water contamination from CCR impoundments and landfills. The EA may therefore underestimate the number of exceedances occurring at immediate receiving waters (see Section 5 ).

In 2010, EPA’s Office of Solid Waste and Emergency Response (OSWER) proposed regulation of CCRs under RCRA (75 FR 35127 – 35264, June 21, 2010). As part of the final CCR rulemaking, OSWER is evaluating ground water contamination associated with combustion residuals in surface impoundments and landfills. The ground water impact analysis for the CCR rulemaking will identify and quantify human health risks to private dri nking water wells due to potential ground water contamination from current CCR management practices. EPA will include the results of its national-scale analysis of ground water impacts in the documentation for the final CCR rulemaking.

4.3 C OMBUSTION 

### R ESIDUALS 

### S URFACE IMPOUNDMENT S AS 

### A TTRACTIVE 

### N UISANCE



### An “attractive nuisance” is an area or habitat that attracts wildlife and is contaminated with pollutants at concentrations high enough to potentially harm exposed organisms. Two methods of handling combustion w astewater, surface impoundments and constructed wetlands, are classified as lentic systems supporting aquatic vegetation and organisms. These methods

have been known to attract wildlife from other terrestrial habitats and therefore can be

considered attrac tive nuisances. As an attractive nuisance, a surface impoundment can impact local wildlife as well as transient species that might rely on them during critical reproduction periods such as seasonal breeding events [Rowe et al., 2002]. Exposure to combustion wastewater during sensitive life cycle events is potentially of concern given that this type of exposure has been associated with complete reproductive failure in various vertebrate species [Cumbie and Van Horn, 1978; Gillespie and Baumann, 1986; Lemly, 1997; Pruitt, 2000].

Organisms that frequent attractive nuisance sites at steam electric power plants, such as surface impoundments, risk exposure to elevated metals concentrations. Documented case studies have shown that terrestrial fauna nesting near co mbustion residuals surface impoundments can have higher levels of arsenic, cadmium, chromium, lead, mercury, selenium, strontium, and vanadium than fauna of the same species at reference sites [Bryan et al., 2003; Burger et al., 2002; Hopkins et al., 1997, 1998, 2000, 2002, 2006; Nagle et al., 2001, Rattner et al., 2006]. Table A -8 in Appendix A s ummari z es documented case studies of attractive nuisances at steam electric power plants

.

36 As part of the benefits and cost analysis, EPA quantified the benefits resulting from improved ground water quality under the proposed Steam Electric ELGs. See the Benefits and Cost Analysis for Proposed Steam Electric Effluent Limitations Guidelines Regulation (DCN SE03172) for more details.Section 4

— Exposure Pathways



### 4-22 In several of these instances, histopathological effects (i.e., changes in pollutant tissue concentrations) were observed. For example, birds nesting near a combustion residu als surface impoundment produced eggs with higher selenium concentrations than eggs found at the reference site. Although egg selenium concentrations near combustion residuals surface impoundments exceeded thresholds that signify adverse effects on reproduction, the study did not observe any reduction in reproductive success [Bryan et al., 2003]. In a study conducted by Hopkins et al. [1998], sediment

from a contaminated combustion residuals surface impoundment had arsenic levels more than 100 times higher than the levels found in reference site sediments. Adult toads captured in the contaminated surface impoundment reported a sevenfold difference in arsenic levels between those from reference sites [Hopkins et al., 1998]. Although the study did not measure any indicators of reduced survival or reproductive success in the toads, the results indicate exposure to combustion residuals surface impoundments are a potential threat [Hopkins et al., 1998].

Multiple studies have linked attractive nuisance areas at steam electric power plants to diminished reproductive success. Field studies have documented adverse effects on reproduction for turtles and toads living near selenium-laden combustion residuals surface impoundments [Hopkins et al., 2006; Nagle et al., 2001]. One laboratory study found that water snakes exposed to prey with elevated selenium concentrations reduced their reproductive success [Hopkins et al., 2002]. In another study, an interior least tern (Sterna antillarum ), an endangered migratory bird, beg an nesting at Gibson Lake, an artificial shallow pond that receives combustion residuals pond effluent from the Gibson Generating Station in Indiana. Within several years, nearby combustion residuals ponds at the Gibson Generating Station were also attract ing nesting least terns, placing these sensitive species in direct contact with combustion wastewater. To address the attractive nuisance problem presented by the ponds, the Gibson Generating Station began a cooperative program with the Indiana Department of Natural Resources to protect the nesting birds by creating a nearby alternative habitat known as the Cane Ridge Wildlife Management Area (WMA) [Pruitt, 2000]. Cane Ridge WMA received water from Gibson Lake and in 2008 the

U.S. Fish and Wildlife Service became concerned about selenium levels in the water and fish present in the Cane Ridge WMA [USFWS, 2008]. Accordingly, the bottom of Cane Ridge was plowed to redistribute and bury the selenium in the soil and the flow of water from Gibson Lake into Cane Ridge was stopped and replaced with water piped from Wabash River. Duke Energy paid to stock the Cane Ridge WMA ponds with fathead minnows to lure back migratory birds. As of June 2009, avocets, dunlins, black terns, Forster’s terns, Caspian terns, and 50 en dangered least terns have returned to Cane Ridge [USFWS, 2012].

Other well

- documented cases of attractive nuisance settings with similar characteristics (e.g., elevated concentrations of specific metals) to those associated with steam electric power plants provide further support that combustion residuals surface impoundments have the Surface impoundments and constructed wetlands can act

as attractive nuisances by attracting wildlife and exposing them to elevated pollutant levels.Section 4

— Exposure Pathways



### 4-23 potential to pose a threat to wildlife. For example, exposed organisms in attractive nuisance settings affected by urban and agricultural wastes have exhibited elevated tissue concentrations of metals, with some organisms experiencing a combination of reproductive or sublethal effects that adversely impact their survival [Clark, 1987; Hofer et al., 2010; King et al., 1994; Ohlendorf et al., 1986, 1988a, 1988b, 1989, 1990; Tsipoura et al., 2008]. Although these case studies do not directly relate to steam electric power plants, they highlight the potential dangers of attractive nuisances and ability for metals to bioaccumulate in the surrounding wildlife [Ohlendorf et al., 1986, 1989, 1990]. Table A-9 in Appendix A summarizes documented case studies not specific to steam electric power plants.Section 5

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### 5-1 

# SECTION 5 CURRENT IMPACTS FROM STEAM ELECTRIC INDUS TRY

As discussed in Section 3 , exposure to combustion wastewater has been associated with fish kills, reductions in the growth and survival of aquatic organisms, behavioral and physiological effects in wildlife and aquati c organisms, and changes to the local habitat [Carlson and Adriano, 1993; Rowe et al., 2002]. As well as directly affecting aquatic ecology and local wildlife, combustion wastewater has had other environmental impacts such as altering local habitats, contaminating drinking water wells, and contributing to fish advisories [U.S. EPA, 2007b]. This section presents the demonstrated environmental impacts of combustion wastewater discharges, including a qualitative discussion of the lethal and sublethal ecologica l effects of pollutants in combustion wastewater, documented instances where combustion wastewater has caused fish advisories or exceeded maximum contaminant levels (MCLs) presenting a potential human health concern, and the results from the U.S Environmental Protection Agency’s ( EPA’s ) quantitative analysis of the potential environmental impacts to surface water quality, potential impacts to ecological receptors (wildlife), and potential impacts to human receptors (human health) under current baseline cond itions within the industry.

5.1 E COLOGICAL 

### I MPACTS



### This section provides examples of the lethal and sublethal effects on organisms exposed to combustion wastewater metals (e.g., arsenic, cadmium, chromium, copper, mercury, and selenium) in surface waters and sediment. Scientific studies reported in the literature included:

• 

### Field studies in which organisms collected from known contaminated sites were compared to those collected from uncontaminated sites.

• 

### Laboratory experiments in which organisms intentionally exposed to combustion wastewater were compared to those unexposed.

Many of the scientific studies documented in the literature focused on selenium as a key pollutant of environmental concern within combustion wastewater. However, due to the complex nature of the wastewater, many studies evaluated the environmental effects of metals in combustion wastewater in aggregate. This section presents the specific lethal and sublethal effects attributed to selenium exposure followed by discussions of the lethal and s ublethal effects of all metals present within combustion wastewater.

5.1.1 Lethal Effects of Selenium

Predicting the impacts of selenium in aquatic ecosystems can be particularly challenging, because selenium can bioaccumulate to toxic levels in organisms inhab iting environments with low selenium concentrations. For example, Lemly conducted a field study that investigated the patterns of selenium biomagnification and toxicity in aquatic organisms inhabiting a cooling

water reservoir that received effluent from a power plant’s ash pond [Lemly, 1985a]. Throughout the study, selenium concentrations in the reservoir averaged 10 micrograms per liter; however, Lemly reported that fish tissue concentrations reached levels ranging from 500 to 4,000 times the

average rese rvoir water selenium concentration. The results of the study indicated that the extent

### 5-2 of selenium bioaccumulation depended on the trophic level of the fish present in the reservoir. Lemly observed that the selenium accumulation increased as the trophic le vel increased, which potentially correlated with the observed elimination of multiple higher tropic level fish species. Therefore, these findings suggest that— even at low concentration within a surface water

— selenium can accumulate and biomagnify to toxic levels in aquatic organisms and pose a lethal threat to fish at the top of the trophic structure [Lemly, 1985a].

In 1977, two years after the initial operation of the Belews Creek Steam Station in North Carolina, the fish community inhabiting the plant’s cooling water reservoir (a lake) underwent rapid decline, and species diversity drastically altered [Lemly, 1985a]. Lemly observed that 17 of the 20 fish species originally present in the lake were eliminated after the power plant began operation, including all game species (temperate perch [ Percichthyidae ], true perch and pike perch [ Percidae ], and sunfish [ Centrarchidae ]). Among the 20 initial fish species, Lemly reported significant levels of selenium accumulation in the eliminated species and statistical ly unchanged levels of selenium accumulation in the surviving species, relative to levels before the power plant began operation. Only three species maintained reproducing populations in the reservoir: one native species (mosquitofish) and two introduced non-native species of minnows (fathead minnows and red shiners) [Lemly, 1985a].

A number of scientific studies expressed concern over selenium exposure within lakes and reservoirs where longer residence times allow for further bioaccumulation and a greate r potential to reach lethal concentrations. In particular, studies concluded that elevated selenium concentrations were likely the primary contributor to fish kills in lakes and reservoirs, decreasing population density and community diversity [Coughlan and Velte, 1989; Crutchfield, 2000b; Crutchfield and Ferguson, 2000a; Cumbie and Van Horn, 1978].

5.1.2 Sublethal Effects of Selenium

The sublethal effects of selenium vary widely and can impact growth, reproduction, and survival of susceptible organisms. Scientists have demonstrated that various fish and amphibian species are sensitive to elevated selenium concentrations such as those found in combustion wastewater. These fish and amphibian species have developed sublethal symptoms such as

accumulation of seleniu m in tissue (histopathological effects) and in the blood (hematological effects), decreased growth, changes in weight, abnormal morphology, and reduced hatching success [Coughlan and Velte, 1989; Sager and Colfield, 1984; Sorensen, 1988; Sorensen and

Bauer , 1984a; Sorensen et al., 1982, 1983, 1984b].

The literature indicates that the extent of selenium accumulation in fish tissue varies by species, and selenium accumulates most significantly in the liver and reproductive tissues in most species [Baumann an d Gillespie, 1986; Sager and Colfield, 1984; Sorensen, 1988]. Other studies have reported accumulation in the skeletal muscle, kidneys, gills, and hearts of fish, resulting in pathological lesions, morphological changes, increased organ weight, and decreas ed growth [Coughlan and Velte, 1989; Sorensen and Bauer, 1984b].

In addition, selenium is highly teratogenic (i.e., able to disturb the growth and development of an embryo or fetus) and readily transferable from mother to egg. Selenium is known to bioaccumulate in the reproductive organs of fish and amphibian species. In one study, Section 5

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### 5-3 ovarian selenium concentrations in bluegill fish were observed at levels 1,000 times greater than the surrounding surface water [Baumann and Gillespie, 1986]. Multiple studies have documented reproductive failure or other forms of diminished reproductive success in both fish and amphibians inhabiting ponds, lakes, and reservoirs contaminated with selenium from combustion wastewater discharges [Baumann and Gillespie, 1986; Crutchfield, 2000b; Cumbie and Van Horn, 1978; Gillepsie et al., 1986; Hopkins et al., 2002; Nagle et al., 2001]. For example, Hopkins et al. [2006] observed reduced hatching success, abnormal swimming, and abnormalities in the face and skull in the offspring of s elenium

- contaminated female toads.

Histopathological effects (i.e., observable changes in tissue), increased metabolic rate, and decreased growth rates are effects typically caused by combustion wastewater contamination. Water and fish samples collected be fore and after the discharge of combustion wastewater from the ash pond to the Texas Utilities Martin Creek Reservoir found that selenium concentrations were significantly elevated in the reservoir and in fish livers, kidneys, and gonads. In 1984, Garrett and Inman reported that elevated selenium concentrations persisted in the livers and kidneys of several species of fish for up to three years after the combustion wastewater discharges ceased. Additionally, a 1988 study by Sorensen found that red ear sunfish native to the reservoir exhibited ovary abnormalities related to elevated selenium concentrations up to eight years following an eight -month exposure to combustion wastewater discharges. Although the ash pond discharge was short-lived, many of the histo pathological effects persisted for years after the discharge had ceased [Rowe et al., 2002].

For a summary of the impacts of selenium on surface water, refer to Table A -10 in Appendix A.

5.1.3 Lethal Effects of Other Metals

Scientific studies have confirmed that both acute and chronic exposure to metals in combustion wastewater can be lethal to a wide range of aquatic organisms. For example, Guthrie and Cherry [1976] found that shrimp darters and salamanders were highly sensitive to acute exposures of combustion wastewater and experienced nearly 100 percent mortality following a

five -day exposure to combustion wastewater discharges. Invertebrates and fish also evaluated in the study were less sensitive to the acute exposure to combustion wastewater and reported lo wer rates of mortality [Guthrie and Cherry, 1976]. Chronic exposures to combustion wastewater are also of concern; however, studies show extreme differences in species sensitivity [Rowe et al., 2002]. For example, juvenile chubsuckers (a benthic fish) exposed for 45 days to sediments, water, and food contaminated with combustion wastewater experienced a 75 percent mortality rate [Hopkins, 2001]. In another study, bullfrogs exposed to sediment and water from a combustion residuals surface impoundment for 34 days demonstrated an 87 percent mortality rate (which was 41 percent greater mortality rate than bullfrogs included in control group) [Rowe et al., 2002]. A third study reported no lethal effects for banded snakes exposed for two years to

fish collected fr om combustion residuals surface impoundments [Hopkins et al., 2002].

Other studies examined lethal effects of sediments contaminated with combustion residuals. For example, eggs and hatchlings of fish and reptiles raised in contaminated sediment reported higher mortality rates (16 to 94 percent) than eggs and hatchlings from control groups [Hopkins et al., 2000; Nagle et al., 2001; Roe et al., 2006; Rowe et al., 1998a, 1998b, 2001; Section 5

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### 5-4 Snodgrass et al., 2004]. In each of the studies, elevated mortality rates were observed in conjunction with higher concentrations of combustion wastewater metals (e.g., arsenic, cadmium, chromium, copper, selenium) in the exposed sediment.

Three studies evaluated the lethal effects of specific metals in combustion wastewater on varying organisms (i.e., insects, fish, and amphibians) and determined the median lethal concentration (LC 50 

### ) for each metal -organism combination. LC 50 

### is the concentration expected to be lethal to 50 percent of a group of organisms exposed for a given time duration. Table 5-1 summarizes the results from the three experiments and Table 5-2 presents the LC 50 

### concentrations reported in the studies. Overall, the LC 50 

### studies report species

- specific differences, particularly among species living downstream of fly ash pond discharges. The downstream species developed resistance to metals compared to those living in unpolluted ponds. Because the LC 50 

### concentrations were much higher than actual aquatic concentrations, there was no evidence in these experiments of acute lethal effects, though long

- term (one to three months) lethal effects could not be ruled out [Benson and Birge, 1985; Birge, 1978; Specht et al., 1984].

Table 5-1. Summary of Studies Evaluating Lethal Effects of

Metals in Combustion Wastewater

Citation Studied Organism Test

Performed Trace Elements

Studied Summary of Results

Birge,

1978 Eggs from goldfish, trout,

and toads 7

- to 28

- day

lethal effects 22 elements Among the 22 elements tested, cadmium, chromium, mercury, nickel, lead, and silver were the most toxic to all three species, with most median lethal concentrations (LC 50 ) being 0.1 milligrams per liter (mg/L) or less.

Benson and Birge,

1985 Minnows (fish) living in fly

ash

- polluted ponds in Kentucky compared to those living in uncontaminated ponds Acute (96

- hour) toxicity Cadmium Copper

Zinc The study found a higher tolerance to cadmium and copper in the exposed fish compared to the fish from unpolluted ponds. However, both exposed and unexposed populations

exhibited similar tol erance to zinc.

Specht et
al., 1984 Insects (coleopterans, mayflies, and other insects) exposed to fly ash pond

effluent from the Appalachian Power Plant in Giles County, Virginia, compared to those living in an uncontaminated pond Acute (96

- hour) toxicity Cadmium Copper

Zinc The study observed a higher tolerance to pollutants in exposed insects compared to those living in unpolluted ponds. Section 5

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### Table 5-2 . Median Lethal Concentrations (LC 50 

### ) for Metals in Combustion Wastewater

Pollutant LC 50 , mg/L

7- to 28

- Day Exposure 96

- Hour Exposure

Trout [Birge, 1997] Goldfish [Birge, 1997] Toad [Birge, 1997] Exposed

Minnows [Benson and Birge, 1985] Control

Minnows [Benson and Birge, 1985] Mayflies [Specht et al., 1984] Other Insects [Specht et al., 1984]

Aluminum 0.56 0.15 0.05

Arsenic 0.54 0.49 0.04

Cadmium 0.13 0.17 0.04 3.89 (a)
9.55 (b) 3.06 (a)
7.16 (b) 0.27 1.2

– 250

Chromium 0.18 0.66 0.03

Cobalt 0.47 0.81 0.05

Copper 0.09 5.2 0.04 0.36 (a)
0.41 (b) 0.21 (a)
0.39 (b) 0.18 0.03

– 8.3

Germanium 0.05 5.6 0.05

Lead 0.18 1.66 0.04

Mercury 0.005 0.12 0.001

Nickel 0.05 2.14 0.05

Selenium 4.18 8.78 0.09

Silver 0.01 0.03 0.01

Vanadium 0.16 4.6 0.25

Zinc 1.06 2.54 0.01 6.14 (a)
5.96 (b) 6.09 (a)
7.45 (b) 18.44 18.2

Acronyms: mg/L (milligrams per l iter ).

Shaded cells indicate that the pollutant was not evaluated.

a – Nominal water hardness of 100 mg/L calcium carbonate (CaCO 3 ).

b

– Nominal water hardness of 250 mg/L calcium carbonate (CaCO 3 ). Section 5

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### 5-6 5.1.4 Sublethal Effects of Other Metals

Although the majority of sublethal effects documented in the literature primarily focus on selenium concentrations in combustion wastewater, several studies discussed the sublethal effects of other pollutants, such as arsenic, cadmium, chromium, copper, and lead [Rowe et al., 2002]. Sublethal effects from exposure to metals other than selenium in combustion wastewater can include changes to morphology (e.g., fin erosion, oral deformities), behavior (e.g., swimming ability, ability to catch prey, ability to escape from predators), and metabolism that can negatively affect long -term survival. For example, a study of larval bullfrogs living in combustion residuals ponds found that more than 95 percent of individuals had abnormal oral structures, such as the absence of grazing te eth or entire rows of teeth, which altered feeding habits and subsequently reduced growth rates in the affected bullfrogs [Rowe et al., 1996]. In another study, tail malformations in larval bullfrogs attributed to combustion wastewater exposure caused abnormal swimming behavior and the affected bullfrogs were preyed upon more frequently than bullfrogs from unpolluted sites [Raimondo et al., 1998].

Several studies have demonstrated increased metabolic rates and decreased growth rates in aquatic organisms exposed to combustion wastewater. Increased metabolism causes organisms to waste energy during normal metabolic processes, which can affect growth. In a 1998 study by Rowe, grass shrimp caged in a combustion residuals pond for eight months experienced a 51 percent increase in standard metabolic rate. Similarly, crayfish captured near the pond experienced increased metabolic rates and decreased growth rates

— effects that were also observed in crayfish collected from unpolluted sites and exposed to contaminated sediments from the combustion residuals pond [Rowe et al., 2002].

5.2 P OTENTIAL FOR 

### H UMAN 

### H EALTH 

### E FFECTS



### Exposure to metals can cause non-cancer effects in humans, including damage to the circulatory, respiratory, or digestive systems and neurological and deve lopmental effects. Combustion wastewater includes toxic metals and known or suspected carcinogens (e.g., arsenic and cadmium). In the literature review, EPA identified potential human impacts from the consumption of fish in contaminated waters and from the ingestion of drinking water contaminated by combustion wastes.

During the late 1970s, three power plant cooling water reservoirs in Texas received discharges from ash ponds containing elevated selenium levels, resulting in a series of fish kills.

The reservoirs included Brandy Branch Reservoir, located in Harrison County, Texas; Welsh Reservoir, located in Titus County, Texas; and Martin Creek Lake, located in Rusk County, Texas. Investigations at the reservoirs implicated elevated selenium levels in the fish tissue as the cause. In 1992, the Texas Department of Health issued a fish consumption advisory for the three reservoirs after determining that the level of selenium in fish could pose a potential health risk to humans, especially children six year s or younger and pregnant women. From samples taken in 1996 and 1997 from Brandy Branch Reservoir, the selenium concentration in 13 largemouth bass, one white bass, and three white crappie averaged 0.87 parts per million (ppm) [ATSDR, 1998a]. From samples taken in 1998 from the Welsh Reservoir, the selenium concentration in 12 largemouth bass, six channel catfish, one flathead catfish, and one common carp averaged 2.7 ppm [ATSDR, 1998b]. From samples taken in 1996 and 1997 from Martin Creek Lake, the Section 5

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### 5-7 seleni um concentration in 17 largemouth bass, 10 channel catfish, two flathead catfish, four black crappie, and one white crappie averaged 2.3 ppm. The national average of selenium concentration in fish ranges between 0.1 and 1.5 ppm [ATSDR, 1998c].

Ground water and drinking water supplies can be degraded by pollutants in combustion wastewater and residuals via leachate [Cross, 1981]. Leachate can migrate from the site in the ground water at concentrations that could contaminate public or private drin king water wells and surface waters, even years following disposal of combustion residuals [NRC, 2006]. For example, in the damage case at the Wisconsin Electric Power Company (WEPCO) facility in Port Washington, Wisconsin, fly ash had been disposed of in a quarry for over 20 years (1943- 1971) before selenium and boron contamination was reported in a private drinking water well at a depth of 40- 60 feet located 250 feet downgradient from the coal- fired power plant waste disposal site [U.S. EPA, 2007b].

As discussed in Section 3 and Appendix A, there have been documented exceedances of MCL drinking water standards at off-site ground water and drinking water wells. The most common pollutants that exceeded their MCL were arsenic, selenium, boron, and manganese (secondary standard) for both combustion residuals surface impoundments and landfills. In addition, exceedances of cadmium and lead

from surface impoundments and s ulfates from landfills were also observed [EIP et al., 2010a and 2010b; MDNRE, 2010; U.S. EPA, 2007b]. Exceedances of MCLs in the ground water indicate potential human health impacts if the pollutants enter private drinking water wells.

Section 3.5.2 outlines three case studies where leachate contamination caused impacts to private drinking water wells.

Exceedances of drinking water

standards can also occur in surface waters. For example, Duke Energy's Riverbend Plant discharges ash pond effluent into Mountain Island Lake, which supplies drinking water to 700,000 people. The county detected arsenic and zinc concentrations above state standards in an area near the ash pond discharge pipe [Ch arlotte Observer, 2010]. As discussed in Section 3.4.4

, most of the pollutants in the surface water and ground water would likely be reduced to safe levels during d rinking water treatment. However, these pollutants could potentially impact the effectiveness of the treatment processes. Approximately 85 percent of steam electric plants are located near public wells and 37 percent are located near a drinking water intake for surface

water.

5.3 Q UANTIFIED 

### E NVIRONMENTAL 

### I MPACTS



### EPA developed the receiving water model described in Section 4.1.2 to quantify the current environmental impac ts of direct surface water discharges of the evaluated waste streams (i.e., flue gas desulfurization (FGD) wastewater, fly ash transport water, bottom ash transport Various case studies document exceedances of drinking

wate r standards at ground water and drinking water wells due to leachate from nearby impoundments and landfills. Section 5

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### 5-8 water, and leachate) from steam electric power plants. This section presents the baseline r esults of the modeled pollutant concentrations in surface waters and fish tissue and their potential impacts to aquatic life, wildlife, and human health.

5.3.1 Water Quality Impacts

The quality of a surface water is defined by its chemical, physical, and biological characteristics and is measured to evaluate a water’s potential to harm aquatic life and human health. EPA assessed the quality of surface waters that receive discharges of the evaluated waste streams by comparing estimated pollutant concentrations in the water column based solely on steam electric industry discharges to the National Recommended Water Quality Criteria (NRWQC) and drinking water MCLs. Based on the modeling results for surface water quality impacts, EPA determined that approximately 67 percent of the lakes, ponds, and reservoirs (24 out of 36) and 47 percent of the rivers and streams (123 out of 261) that receive discharges of evaluated waste streams are experiencing a quantifiable reduction in water quality due to those discharges.

Based on the modeling results, human health criteria exceedances are more prevalent among the immediate receiving waters than aquatic life criteria exceedances. Approximately 20

to 49 percent of the immediate receiving waters had modeled water concentrations that exceed a human health criterion, while approximately 10 to 23 percent of the immediate receiving waters had modeled water concentrations that exceed an aquatic life criterion. The difference between exceedances for human health and aquatic life criteria is due to the significantly lower human health criteria, when compared to aquatic life criteria.

Table 5-3 presents the number and percentage of immed iate receiving waters with estimated water concentrations that exceed each water quality criterion. These exceedances are based solely on discharges from steam electric power plants. For the model, EPA did not include any additional sources of pollutants (e.g., naturally-occurring metals, non-point source discharges, or other point source discharges).

The reduced water quality presented in Table 5 -3 is primarily attributed to total arsenic, total thallium, dissolved cadmium, and total selenium concentrations in the water column. For human health, estimated water concentrations exceeded criteria primarily for arsenic, thallium, and cadmium. For instance, 147 out of the 297 immediate receiving waters exceed the human health NRWQC for the consumption of arsenic-contaminated water and organisms (0.018 micrograms per liter [μg/L]); 96 exceed the NRWQC for consumption of organisms only (0.14 μg/L) ; and 19 exceed the MCL (10 μg/L). Therefore, humans consuming water and/or organisms inhabiting these waters are more at risk to skin damage, cardiovascular disease, and cancer in the skin, lungs, bladder, and kidney. In comparison, aquatic organisms are at risk f or exposure to cadmium and selenium. This is because, for example, estimated water concentrations in more than 13 percent of the immediate receiving waters (40 out of 297) exceed the aquatic life criterion for chronic exposure to cadmium- and selenium-contaminated waters (0.25 and 5 μg/L, respectively). Therefore, aquatic organisms inhabiting these waters are under a greater threat for

cadmium

- related effects (tissue damage and organ abnormalities) and selenium

- related effects (reduced growth, increased metabolic rates, reproductive failure, and death). Sublethal and lethal Section 5

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### 5-9 impacts from chronic selenium exposure are frequently cited in literature. For more information on these impacts, refer to Section 5.1

.

Table 5-3 . Number and Percentage of Immediate Receiving Waters with Estimated Water Concentrations that Exceed the Water Quality Criteria

Evaluation Criterion Number of Immediate Receiving Waters Exceeding a Criterion a

Number of

Rivers and

Streams Number of Lakes, Ponds,

and

Reservoirs Total Immediate Receiving

Waters b

Number Exceeding Percentage Exceeding
Aquatic

Life

Criteria Freshwater Acute NRWQC 27 4 31 10%
Freshwater Chronic NRWQC 53 14 67 23%

Human

Health

Criteria Human Health Water and Organism NRWQC 123 24 147 49%

Human Health Organism Only NRWQC 84 15 99 33%

Drinking Water MCL 47 12 59 20%
Total Number of Unique Immediate Receiving Water s c 123 24 147 49%

Acronyms: NRWQC ( National Recommended Water Quality Criteria ); MCL (M aximum C ontaminant L evel ).

a – A total of 297 immediate receiving water s (261 rivers and streams; 36 lakes, ponds , and reservoirs) were

included in the water quality model [ERG, 2013h]

.
b

– These values are the sum and percentage of rivers, streams, lakes, ponds, and reservoirs impacted.

c – This represents the number of unique immediate receiving waters that exceeded at least one criterion.



### Table F -1 in Appen dix F presents additional details on the number and percentage of

immediate receiving waters that are exceeding each water quality criterion by pollutant

. For

more detailed information on the modeled immediate receiving water concentrations under baseline conditions see Figures F-1 to F-10 and Tables F-2 to F-11 in Appendix F.

5.3.2 Wildlife Impacts

As part of the wildlife impacts analysis, EPA assessed the impacts of the evaluated waste streams on the following categories:

• 

### Impacts to aquatic life due to changes in water quality;

• 

### Impacts to wildlife from contact with contaminated sediment; and

• 

### Impacts to wildlife from consumption of contaminated fish.

Bioaccumulative metals in surface waters from steam electric discharges are known to accumulate through the food chain and affect local wildlife populations. Selenium is of particular concern in aquatic environments because it can accumulate in sediment an d biomagnify to toxic levels in fish inhabiting selenium

- contaminated waters (even at relatively low selenium concentrations), potentially eliminating piscivorous (fish -eating) wildlife higher in the food chain [Ohlendorf et al., 1988a]. Impacts to fish populations are well documented in the literature for

selected case studies [Garrett and Inman, 1984; Lemly, 1985a; Sorensen et al., 1982]. To expand Section 5

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### 5-10 beyond the case study sites and assess the broader impacts steam electric discharges pose to local fish populations, EPA modeled selenium concentrations in fish tissue and compared these concentrations to concentrations documented in the literature as causing reduced reproductive success and histopathological effects in fish. Table 5-4 presents the number and percentage of immediate receiving waters with estimated selenium fish tissue concentrations that exceed the documented impact selenium concentrations in trophic level 3 (T3) and trophic level 4 (T4) fish.

According to the modeling results, estimated fish tissue concentrations of selenium in approximately 12 to 18 percent of the waters receiving discharges that were evaluated exceeded levels with known impacts to fish, with the precise number of exceedances depending on the trophic level of the fish. Although these fish populations may not be experiencing lethal impacts, the sublethal damage to their reproductive systems may eventually impact the overall suc cess of the fish populations near steam electric power plants. As was observed in the Belews Lake case study, this is especially an issue in lakes, ponds, and reservoirs, where healthy fish populations cannot migrate and seek out alternative food sources. Decreased fish populations may alter the structure of these aquatic communities and cause cascading effects within the food web that can impact the success of other organisms in the ecosystem.

For more information on the potential environmental impacts fro m selenium exposure,

refer to the selenium discussions in Sections 3.1 and 5.1 . For more detailed information on

baseline modeled fish tissue concentrations in the immediate receiving water for selenium and

other metals evaluated in the EA see Figures F -11 to F-21 and Tables F -12 to F-22 in Appendix F.

Table 5-4 . Comparison of Modeled Selenium Concentrations in Fish Tissue to Documented

Concentrations of Selenium in Fish Tissue Known to Cause Adverse Effects

Wildlife

Affected Trophic

Level Documented Impact Selenium

Concentration (μg/g) b Number of Immediate Receiving Waters Exceeding

Documented Concentrations a

Number of

Rivers and

Streams Number of
Lakes, Ponds, and

Reservoirs Total Receiving Waters c

Number Exceeding Percentage Exceeding

Largemouth

bass (Micropterus salmoides) T4 Female carcass =

2.86 44 9 53 18%

Male carcass =

2.63 45 9 54 18%

Bluegill (Lepomis macrochirus) T3 Female carcass =

2.74 33 7 40 13%

Male carcass = 4.64 29 7 36 12%

Acronyms: μg/g ( m icrograms per g ram).

a – A total of 297 immediate receiving waters (261 rivers and streams; 36 lakes, ponds, and reservoirs) were included in the wildlife model ( ERG, 2013i; ERG, 2013j).

b

– Baumann and Gillespie [ 1986 ] concluded that the documented selenium concentrations that accumulated i n the fish carcasses resulted in negative reproductive and histopathological effects.

c – These values are the sum and percentage of rivers, streams, lakes, ponds, and reservoirs impacted. Section 5

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### 5-11 EPA also assessed the potential impact to wildlife exposed to sedi ments in surface waters that receive discharges of the evaluated waste streams by comparing estimated pollutant

concentrations in the sediment to EPA’s Assessment and Remediation of Contaminated Sediments (ARCS) Program Guidelines

. 37 

### As discussed in Section 4.1.2 , the wildlife model expresses the potential impact to wildlife in terms of a hazard quotient (HQ). An HQ is the ratio of concentration in contaminated media to a concentration benchmark. An HQ greater than 1 indicates a potential impact to wildlife for the endpoint associated with the benchmark value.

EPA calculated that only 1 percent of rivers and streams (3 out of 261) considered in this

assessment and zero percent of lakes, ponds, and reservoirs had estimated sediment pollutant concentrations that may be toxic to wildlife. These results may underrepresent the impact to wildlife from sediment contamination, primarily due to certain assumptions and limitation s of the model. Specifically, the immediate receiving water model evaluates only a snap shot in time following exposure to average annual loadings. The modeling does not take into account accumulation of pollutants in sediments over time either in the lake or river environment. It is likely that cumulative accumul ations over multiple years of loadings would result in sediment concentrations considerably higher than the modeling results predict. As support for this interpretation, several publications in the literature confirm that sediment exposure impacts are

more likely to occur in lake environments where pollutants can accumulate in sediments over time [Hopkins et al., 2000, 2003; Lemly, 1997].

In addition to direct impacts on fish and other aquatic life, EPA identified numerous literature articles documenting i mpacts from bioaccumulative metals on the surrounding wildlife. To quantify the potential impacts of the evaluated waste streams on the surrounding wildlife, EPA selected minks and eagles as indicator species to assess the threat to piscivorous species in the areas of concern. Eagles and minks are distributed across much of the United States and a majority of their diets are composed of fish, making them appropriate indicator species for a

national assessment of bioaccumulation through the foodweb from consumption of fish.

EPA assessed the potential impact to piscivorous wildlife from the evaluated waste streams by modeling fish tissue metal concentrations and comparing these concentrations to no effect hazard concentrations (NEHC) for minks and eagles developed by the U.S. Geological Survey (USGS). Based on the estimated fish tissue concentrations, EPA determined that approximately 43 percent of the immediate receiving waters (129 out of 297) pose a threat to eagles and 33 percent of the immediate receiving waters (99 out of 297) pose a threat to minks through the consumption of contaminated fish. This result demonstrates that estimated pollutant concentrations in fish that inhabit receiving waters immediately downstream from combustion wastewater discharges pose a reproductive threat to surrounding minks and eagles and is an indication of the potential broader impacts combustion wastewater discharges may pose to the greater environment as metals transfer from the aquatic environment and begin to accumulate in

terrestrial food webs.

As expected, modeling results indicated that pollutant concentrations in fish inhabiting lakes, ponds, and reservoirs are more likely to exceed adverse effect benchmarks for wildlife that consume fish compared to pollutant concent rations in fish inhabiting rivers and streams. EPA

37 The ARCS benchmarks did not include mercury. EPA used an alternative benchmark as listed in Table D

- 1 in Appendix D. Section 5

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### 5-12 determined that the estimated fish tissue concentrations would pose a threat to minks and eagles in approximately 78 percent of lakes, ponds, and reservoirs (28 out of 36) that were evaluated and in 39 percent of rivers and streams (101 out of 261) that were evaluat ed. These results are expected, since fish populations inhabiting lake environments cannot travel to uncontaminated

waters and, therefore, continue to bioaccumulate pollutants.

Table 5-5 presents the number and percentage of immediate receiving water s that exceed the USGS wildlife fish consumption NEHC for minks and eagles.

Table 5-5 . Number and Percentage of Immediate Receiving Waters That Exceed Wildlife Fish Consumption NEHC for Mink and Eagle

Evaluation Criterion Number of Immediate Receiving Waters with HQ >1 a

Number of Rivers

a nd Streams Number of Lakes, Ponds, and

Reservoirs Total Receiving Waters b

Number Exceeding Percentage Exceeding Mink fish consumption

NEHC 77 22 99 33%

Eagle fish consumption

NEHC 101 28 129 43%

Total Number of Unique Immediate Receiving

Water s c 101 28 129 43%

Acronyms: HQ ( Hazard Q uotient ); NEHC ( No E ffect H azard C oncentration ).

a – A total of 297 immediate receiving water s (261 rivers and streams; 36 lakes, ponds, and reservoirs) were

included in the wildlife model [ERG, 2013i]

. b

– These values are the sum and percentage of rivers, streams, lakes, ponds, and reservoirs impacted.

c – This represents the number of unique immediate receiving waters that exceed a criterion.



### The pollutants found to present the greatest threat to minks and eagl es from fish consumption were mercury and selenium. Approximately 32 to 43 percent of the immediate receiving waters contained fish with modeled mercury concentrations exceeding the NEHC benchmark for mink or eagle fish consumption, and approximately 15 to 16 percent of the

immediate receiving waters contained fish with modeled selenium concentrations exceeding a fish consumption NEHC benchmark for mink or eagle.

Table 5-6 presents the number and percentage of immediate receiving water s that exceed a USGS wildlife fish consumption NEHC for minks and eagles by pollutant. Section 5

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### 5-13 Table 5-6 . Number and Percentage of I mmediate Receiving Waters That Exceed Wildlife Fish Consumption Hazard Quotients for Mink and Eagle by Pollutant

Pollutant Mink Eagle

Fish Consumption

NEHC a Immediate Receiving Waters with HQ >1 Fish Consumption

NEHC a Immediate Receiving Waters

with HQ >1

Number Exceeding b Percentage Exceeding Number Exceeding b Percentage Exceeding

Arsenic 7.65 2 <1 % 22.4 0 0%

Cadmium 5.66 12 4% 14.7 9 3%

Chromium VI 17.7 c 0 0% 26.6 c 0 0%
Copper 41.2 0 0% 40.5 0 0%

Lead 34.6 1 <1 % 16.3 3 1%
Mercury 0.37 96 32% 0.5 127 43%

Nickel 12.5 0 0% 67.1 0 0%

Selenium 1.13 48 16% 4 46 15%

Thallium ID NC NC ID NC NC

Zinc 904 2 <1 % 145 11 4%

Acronyms: HQ ( Hazard Q uotient ); ID ( Insufficient D ata; no benchmarks were identified in the wildlife HQ analysis

for thallium); NC ( Not C alculated ); NEHC ( No E ffect H azard C oncentration ).

a – The wildlife fish consumption NEHC represents the maximum pollutant concentration in the fish will result in no observable adverse effects in wildlife (i.e., minks or eagles) [USGS, 2008].

b

– A total of 297 immediate receiving water s (261 rivers and streams; 36 lakes, ponds, and reservoirs) were

included in the wildlife model [ERG, 2013i]

.

c – An NEHC benchmark is not available for chromium VI; therefore, EPA used the total chromiu m benchmark.



### 5.3.3 Human Health Impacts

In addition to the assessment of water quality impacts on human health discussed in

Section 5.3.1 , EPA expanded the analysis to evaluate human health impacts from consumption of

fish in immediate receiving waters downstream from discharges of the evaluated waste streams. The purpose of this analysis is to evaluate the broader bioaccumulative effects of metals in steam

electric disch arges and account for the potential for average daily doses of pollutants from fish consumption to exceed human health thresholds where water concentrations may not indicate an issue. EPA evaluated multiple human cohorts (i.e., recreational and subsistence fishers, children and adults) by calculating the average daily dose of metals from fish consumption using the estimated fish tissue concentrations calculated in the model. EPA varied the fish consumption rate and body weight of each cohort (based on age) to determine the average and long- term daily doses for each pollutant. EPA calculated the lifetime excess cancer risk (LECR) based on estimated fish tissue concentrations of inorganic arsenic and calculated non- cancer threats by comparing the average daily doses to threshold values for all metals with published reference doses. For more information on how EPA identified potential impacts to human receptors, see

Section 4.1.2

.

Table 5-7 presents the number and percentage of immediate receiving water s where the estimated LECR for the human receptor exceeded the selec ted threshold, 1- in -1,000,000 cancer

risk for arsenic. EPA determined that arsenic concentrations in fish resulted in an estimated cancer risk greater than 1

- in -1,000,000 to adult subsistence fishers in approximately 9 percent of Section 5

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### 5-14 the immediate receiving wa ters (27 out of 297). Cancer risks for the remaining cohorts were much lower, with LECRs exceeding the cancer risk threshold in 1 to 4 percent of the immediate receiving waters. The human health model presents the risk results for each age group individually to allow for further manipulation in the benefits analysis. The true cancer risk to a child would depend on the amount of time the child consumed fish from locations downstream from steam electric discharges. For example, the cancer risk for a 6

- year -old child who was born and raised in the same place would be the sum of the LECRs from the 1 to <2 years, 2 to <3 years, and 3 to <6 years cohort groups.

Table 5-7 . Number and Percentage of Immediate Receiving Water s That Exceed Human Health Evaluation Criteria (Lifetime Excess Cancer Risk) for Inorganic Arsenic

Receptor Cohort Exposure

Duration (Years) Number of Immediate Receiving Waters Where

Lifetime Excess Cancer Risk Exceeds 1

- in

- a

- Million a, b

Number of

Rivers and

Streams Number of Lakes, Ponds,

and Reservoirs Total Receiving Waters c

Number Exceeding Percentage Exceeding

Child

recreational

fisher 1 to <2 years 1 2 0 2 1%
2 to <3 years 1 2 0 2 1%
3 to <6 years 3 3 0 3 1%
6 to <11 years 5 5 0 5 2%
11 to <16 years 5 3 0 3 1%
16 to <21 years 5 3 0 3 1%

Adult recreational fisher 49 12 

### 0 12 4%

Child

subsistence

fisher 1 to <2 years 1 7 0 7 2%
2 to <3 years 1 7 0 7 2%
3 to <6 years 3 9 0 9 3%
6 to <11 years 5 9 0 9 3%

11 to <16 years 5 9 0 9 3%
16 to <21 years 5 9 0 9 3%

Adult subsistence fisher 49 25 

### 2 27 9%

a – A total of 297 immediate receiving water s (261 rivers and streams; 36 lakes, ponds, and reservoirs) were

included in the human health model [ERG, 2013i]

. b

– Inorganic arsenic cancer slope factor of 1.5 per milligram per kilogram per day.

c – These values are the sum and percentage of rivers, streams, lakes, ponds, and reservoirs impacted.



### A limitation of the modeling that may result in an underestimate of the cancer risk is the fact that the risks are based on an exposure to an average annual loadings; the model does not consider the potential for pollutants to accumulate over time in the environment. The model estimates a minimal cancer risk from consuming fi sh in lakes, ponds, and reservoirs that receive discharges of the evaluated waste streams. The cancer risk is likely greater in a lake environment, where fish are limited in their food sources and can accumulate pollutants over a longer exposure period than is represented in the model. Even given the limitations of the modeling framework, EPA determined that the inorganic arsenic concentrations in fish in 6 percent of the lakes pose a cancer risk to adult subsistence fishers.

Based on the estimated fish tissue concentrations and pollutant average daily doses by cohort, EPA determined that subsistence fishers (adults and children) would have the greatest Section 5

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### 5-15 threat for non- cancer health effects. This was because the average daily do ses (for one or more pollutant) exceeded the oral reference dose values in 57 to 66 percent of the immediate receiving waters, depending on the age group evaluated. Recreational fishers (adult or child) have less of a threat, with average daily doses excee ding oral reference doses in 36 to 43 percent of the

immediate receiving waters. These results suggest that fish downstream from discharges of the evaluated waste streams pose a non -cancer health threat to surrounding fisher populations. Given

the limitati ons of the model described above, these results may underestimate the non- cancer health impacts posed by fish in the lake environment.

Table 5-8 presents the number and percentage of immediate receiving water s where one more pollutant average daily dose exceeds an oral reference dose for non

- carcinogens.

Table 5-8 . Number and Percentage of Immediate Receiving Water s That Exceed Non

- Cancer Oral Reference Dose Values

Receptor Cohort Exposure

Duration (Years) Number of Immediate Receiving Waters Where Estimated Exposure Doses Exceed Non

- Can cer Reference Doses a

Number of

Rivers and

Streams Number of Lakes, Ponds,

and Reservoirs Total Receiving Waters b

Number Exceeding Percentage Exceeding

Child

recreational

fisher 1 to <2 years 1 97 27 124 42%
2 to <3 years 1 97 27 124 42%

3 to <6 years 3 93 27 120 40%
6 to <11 years 5 90 26 116 39%
11 to <16 years 5 85 23 108 36%
16 to <21 years 5 85 23 108 36%

Adult recreational fisher 49 100 28 128 43%

Child

subsistence

fisher 1 to <2 years 1 161 32 193 65%
2 to <3 years 1 161 32 193 65%
3 to <6 years 3 164 32 196 66%
6 to <11 years 5 158 31 189 64%
11 to <16 years 5 137 31 168 57%
16 to <21 years 5 137 31 168 57%

Adult subsistence fisher 49 158 31 189 64%

Acronym: HQ ( Hazard Q uotient ).

a – A total of 297 immediate receiving water s (261 rivers and streams; 36 lakes, ponds, and reservoirs) were

included in the human health model [ERG, 2013i]

. b

– These values are the sum and percentage of rivers, streams, lakes, ponds, and reservoirs impacted.



### According to the exposure doses calculated from the estimated fish tissue concentrations, methylmercury poses the greatest threat to cause non

- cancer health effects in humans from fish consumption. EPA determined that fish mercury concentrations pose a non- cancer threat to humans in approximately 65 percent of the immediate receiving waters. Therefore, humans who

consume mercury -contaminated fish inhabiting these waters would be at risk for developing

mercury -related effects, which could include neurologica l symptoms (e.g., affecting fine motor function, language skills, verbal memory) and cardiovascular disease if at exposed at high enough doses. In addition, EPA determined that fish thallium concentrations pose a non- cancer Section 5

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### 5-16 threat to humans in approximately 40 percent of immediate receiving waters

. 38 

### Therefore,

humans who consume thallium- contaminated fish inhabiting these waters are more likely to develop neurological symptoms (e.g., weakness, sleep disorders, muscular problems), alopecia (i.e., loss of hair from the head and body), and gastrointestinal effects (e.g., diarrhea and vomiting).

Table 5-9 presents the number and percentage of immediate recei ving water s where average daily doses exceed an oral reference dose for non -carcinogens by pollutant.

Table 5-9 . Number and Percentage of Immediate Receiving Waters That Exceed Non

Cancer Oral Reference Dose V alues by Pollutant

Pollutant Oral

Reference Dose (mg/kg/d) Number of Immediate Receiving Waters Where HQ>1

for Non

- Cancer Reference Doses
Number Exceeding a Percentage Exceeding
Inorganic arsenic 0.0003 (b) 3 1%

Cadmium 0.001 (b) 28 9%

Chromium VI 0.003 (b) 0 0%
Copper (c) 0 0%

Lead ID NC NC
Mercury (as methylmercury) 0.0001 (b) 193 65%
Nickel (soluble salts) 0.02 (b) 0 0%

Selenium 0.005 (b) 45 15%
Thallium (soluble salts) 0.00001 (d) 118 40%

Zinc 0.3 (b) 10 3%

Acronyms: NC (Not Calculated); ID (Insufficient Data; there is no current reference dose for lead).

a – A total of 297 immediate receiving waters (261 rivers and streams; 36 lakes, ponds, and reservoirs) were included in the human health model [ERG, 2013i].

b

– U.S. EPA, 2011c.

c – ATS DR, 2010a.

d

– U.S. EPA, 2010 a.



### States, territories, and authorized tribes have the primary responsibility to protect residents from the health risks of consuming contaminated non- commercially caught fish. They inform the general population, including recreational and subsistence fishers, typically by issuing advisories that notify the public that chemical contamination found in local fish may present a public health hazard.

EPA modeled concentrations in T4 fish tissue and compared them to fish consumption advisory screening values to assess the potential for discharges of the evaluated waste streams to cause or contribute to fish advisories and pose a human health hazard. Based on the modeling analysis, EPA determined that up to 73 percent of the immediat e receiving waters included in the analysis would contain fish with contamination levels that would likely trigger advisories for recreational and subsistence fishers. Mercury and selenium were the pollutants most likely to

38 EPA u sed the chronic oral exposure value cited in U.S. EPA, 2010a for thallium chloride as the reference dose. Section 5

— &XUUHQW,PSDFWVIURP6WHDP(OHFWULF,QGXVWU\

### 5-17 trigger a fish advisory. This re sult indicates that steam electric power plants are contributing to the already widespread concentrations of mercury and selenium in fish throughout the country.

Table 5-10 presents the number and percentage of immediate receiving waters where the modeled T4 fish tissue concentrations exceed screening values used for fish advisories.

Table 5-10. Comparison of T4 Fish Tissue Concentrations to Fish Advisory Screening Values

Pollutant Recreational Fishers Subsistence Fishers
Screening

Value (ppm) a Number Exceeding b Percentage Exceeding Screening

Value (ppm) a Number Exceeding b Percentage Exceeding Inorganic arsenic (noncarcinogen) 1.2 0 0% 0.147 3 1%

Inorganic arsenic (carcinogen) 0.026 7 2% 0.00327 14 5%

Cadmium 4.0 13 4% 0.491 30 10%
Mercury (as methylmercury) 0.4 133 45% 0.049 216 73%

Selenium 20 33 11% 2.457 54 18%

a – Screening values are defined as concentrations of target analytes in fish or shellfish tissue that are of potential public health concern and that are used as threshold values against which levels of contamination in similar tissue collected from the ambient environment can be compared. Exceedance of these screening values should be taken as

an indication that more intensive site

- specific monitoring and/or evaluation of human health risk should be

conducted [ U.S. EPA, 2000 a , Table 5 -3].

b

– A total of 2 97 immediate receiving water s (261 rivers and streams; 36 lakes, ponds, and reservoirs) were

included in the human health model [ERG, 2013i]

. Section 5

— &XUUHQW,PSDFWVIURP6WHDP(OHFWULF,QGXVWU\Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-1 

# SECTION 6 ENVIRONMENTAL IMPROV EMENTS
UNDER THE PROPOSED R EGULATORY OPTIONS

In Section 5 , the U.S. Environmental Protection Agency ( EPA ) presented the environmental impacts to surface water quality, wildlife, and human health estimated with EPA’s receiving water model resulting from current (baseline) combustion wastewat er discharges. Under the proposed Steam Electric effluent limitation guidelines and standards ( ELGs ) , EPA

evaluated eight regulatory options ( Table 6-1 ). As part of this quantitative EA, EPA evaluated the environmental improvements associated with th e reduction in pollutant loadings from the

evaluated waste streams —i.e., flue gas desulfurization ( FGD ) wastewater, fly ash transport water, bottom ash transport water, and leachate —under each option. 39 

### Section 8 of the Technical Development Document for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (TDD) (DCN SE01964 ) details the technology options for all waste streams evaluated under each regulatory option considered in support of the proposed ELGs. As described in Section 8 of the TDD, EPA is proposing four preferred alternatives for the new Best Available Technology Economically Achievable (BAT) limitations and Pretreatment Standards for Existing Sources (PSES requirements (i.e., Regulatory Options 3a, 3b, 3, and 4a) under the proposed ELGs. EPA is proposing Regulatory Option 4 for the new NSPS and PSNS requirements. See Section 12 of the TDD for further information on the limitations and standards of the preferred options. This section presents the improvements to surface water quality, wildlife, and human health estimated in EPA’s receiving

water model projected to result from the proposed ELGs.

Based on the quantitative and qualitative analyses performed for the EA, EPA estimated a variety of environmental improvements to result from the reductions in pollutant loadings

associated with the regulatory options . In particular, the EA evaluated 1) improvements in water quality, 2) reduction in threats to wildlife, 3) reduction in human health cancer risks, 4) reduction

in threat s for non- cancer human health effects, and 5) other unquantified environmental improvements. Table 6-2 lists the quantified and unquantified environmental improvements

estimated to result from the preferred options under the proposed Steam El ectric ELGs and designates which quantified improvements were monetized in the benefits analysis described in

the Benefits and Cost Analysis for Proposed Steam Electric Effluent Limitations Guidelines Regulation (DCN SE03172 ) ( Benefits and Cost Analysis ).

For five of the regulatory options (Options 1, 2, 3, 4, and 5), EPA modeled improvements using the receiving water model, as described in Appendices C (Water Quality Model Methodology), D (Wildlife Model Methodology), and E (Human Health Model Methodology).

39 In addition to the waste streams listed in Table 6-1 , EPA evaluated technology options associated with FGMC wastewater, gasification wastewater, and nonchemical metal cleaning wastes as part of the regulatory options. However, no plants current ly discharge FGMC wastewater; all existing gasification plants are operating the technology used as the basis for the regulatory option; and the proposed limitations and standards for nonchemical metal cleaning wastes are equal to current BPT limitations f or existing direct dischargers. Therefore, EPA estimated zero compliance costs and zero pollutant reductions associated with these waste streams and did not include these

two waste streams in the EA.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-2 EPA then applied adjustment factors to this modeled output to estimate improvements for Options 3a, 3b, and 4a, as described in Appendix G (Methodology for Non-Modeled Options).6-3 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-1. Regulatory Options Evaluated in the EA

Waste

Stream Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

FGD

wastewater Chemical precipitation Chemical precipitation + biological

treatment Best Professional Judgment (BPJ)

determination Chemical precipitation + biological treatment for units at a facility

with a total wet

scrubbed capacity of 2,000 MW and
more; BPJ

determination for <2,000 MW Chemical precipitation + biological

treatment Chemical precipitation + biological

treatment Chemical preci pitation + biological

treatment Chemical precipitation + evaporation

Fly ash

transport

water Impoundment Impoundment Dry handling Dry handling Dry handling Dry handling Dry handling Dry handling

Bottom ash

transport

water Impoundment Impoundment Impoundment Impoundment Impoundment Dry handling/ closed loop
(for units >400 MW); impoundment for
units ≤400 MW Dry handling/ closed loop Dry handling/ closed loop

Leachate Impoundment Impoundment Impoundment Impoundment Impoundment Impoundment Chemical precipitation Chemical precipitation

Acronym: MW ( m egawatt)

.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-4 Table 6-2 . Description of Environmental Improvements

from Preferred Regulatory Options

Assessment

Category Description of Environmental Improvement Improvement Quantified Improvement

Monetized More Information

Water Quality Reduction in number of immediate receiving waters exceeding an acute or chronic aquatic life NRWQC  Section 6.2 and

Section 6.3

Reduction in number of immediate receiving waters exceeding a human health NRWQC  Section 6.2 and

Section 6.3

Reduction in number of immediate receiving waters exceeding MCLs  Section 6.2 and

Section 6.3
Increased aesthetics from improved water clarity, color, odor, including nearby s ite amenities (residing, working, traveling)   Benefits and Cost Analysis a

Improved swimming, fishing, boating, and near

- water activities from improved water quality   Benefits and Cost Analysis a

Improved quality of source water used for drinking , irrigation, and

industrial use Qualitative Discussion ( Benefits and Cost Analysis )
Increased property values from water quality improvements Qualitative Discussion ( Benefits and Cost Analysis )
Increased quantity and quality of recreational opportunities Qualitative Discussion ( Benefits and Cost Analysis )
Reduction in pollutant loadings to impaired waters  Section 6.4

Reduction in pollutant loadings to the Great Lakes and Chesapeake Bay  Section 6.4

Reduction in loadings of metals, chlorides, and, TDS to receiving

waters  Section 6.1

Reduction in nutrient loadings to receiving waters   Section 6.1 and

Benefits and Cost Analysi s a

Reduced risk of surface impoundment failures due to surface impoundment closures   Benefits and Cost Analysis a

Reduced sediment contamination Qualitative Discussion ( Benefits and Cost Analysis )
Reduced pollutant leachate to ground

water, reducing contamination and increasing availability of ground

water resources   Benefits and Cost Analysis aSection 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-5 Table 6-2 . Description of Environmental Improvements

from Preferred Regulatory Options

Assessment

Category Description of Environmental Improvement Improvement Quantified Improvement

Monetized More Information

Wildlife Reduced exposure among minks to pollutants that bioaccumulate in fish  Section 6.2 and

Section 6.3
Reduced exposure among eagles to pollutants that bioaccumulate in fish  Section 6.2 and

Section 6.3

Reduction in selenium concentrations

in fish  Section 6.2.2 and

Section 6.3.3
Improved habitat and thus potential

increase in threatened and endangered popu lation   Section 6.4 and

Benefits and Cost Analysis a
Improved fisheries yield and harvest quality due to aquatic habitat improvement Qualitative Discussion ( Benefits and Cost Analysis )
Enhanced existence, option, and bequest values from improved ecosystem health   Benefits and Cost Analysis a

Reduced risks to aquatic life from exposure to steam electric pollutants  Benefits and Cost Analysis a
Reduced exposure to pollutants

associated with the waste streams of concern in surface impoundments

that serve as attractive nuisances Qualitative Discussion (Section

6.5 )

Reduced water usage Qualitative Discussion ( Benefits and Cost Analysis )

Human

Health Reduced exposure to non

- cancer pollutants for recreational and

subsistence fishers   Section 6.2 and

Section 6.3 , Benefits and Cost Analysis a

Reduced cancer risk in recreational

fishers and subsistence fishers   Section 6.2 and

Section 6.3

, Benefits and Cost Analysis a

Reduced adverse health effects from

reduction in

- utero mercury exposure from maternal fish consumption   Benefits and Cost Analysis a

Reduced adverse health effects from reduction in childhood exposure to lead from fish consumption   Benefits and Cost Analysis a

Reduced adverse health effects from reduction in adult exposure to lead from fish consumption Qualitative

Discussion ( Benefits and Cost Analysis )
Reduced adult mortality from air pollutant emissions   Benefits and Cost Analysis a

Reduced social cost of carbon b   Benefits and Cost Analysis a
Reduced exposure to pollutants from

recreational water uses Qualitative

Discussion ( Benefits and Cost Analysis )Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-6 Table 6-2 . Description of Environmental Improvements

from Preferred Regulatory Options

Assessment

Category Description of Environmental Improvement Improvement Quantified Improvement

Monetized More Information Reduced injury associated with impoundment failures Qualitative

Discussion ( Benefits and Cost Analysis )

Reduction in number of immediate receiving waters exceeding fish consumption advisory screening

values  Section 6.4

Acronyms: MCL ( Maximum C ontaminant L evel ); NRWQC ( National Recommended Water Quality Criteria ); TDS ( Total D issolved S olids ).

a – The Benefits and Cost Analysis quantifies and monetizes individual environmental improvements for Options 1

- 5, while inferring total benefits for Options 3a, 3b, and 4a. See Benefits and Cost Analysis for more detail.

b

– Social cost of carbon is an estimate of the monetized damages associated with an incremental increase in carbon emissions in a given year. It is intended to include (but is not limited to) changes in net agricultural productivity, human health, property damages from increased flood risk, and the value of ecosystem services due to climate change

.



### 6.1 L OADING 

### R EDUCTIONS 

### U NDER THE 

### P ROPOSED 

### R EGULATORY 

### O PTION S



### EPA estimates that the preferred options will significantly reduce pollutant loadings to receiving waters for the 10 metals in the EA model and for other pollutants that can adversely

affect surf ace waters, such as boron, manganese, nutrients, chlorides, and total dissolved solids ( TDS ). Table 6-3 and Table 6-4 present the reduction in pollutant discharge loadings under the regulatory options for the evaluated waste streams.

As discussed in Section 4 , the EA focused on toxic, bioaccumulative metals discharged to surface waters in the evaluated waste streams. EPA determined that the preferred ELG options will reduce these metal loadings by as much as 70 perce nt for arsenic and 77 percent for chromium VI (under Options 3a and 3b), 92 percent for selenium and 95 percent for manganese (under Option 3 ), and 96 percent for selenium and 97 percent for manganese (under Option 4a). In turn, these pollutant reductions will reduce the negative impacts on the environment and reduce the potential exposure of these contaminants to ecological and human receptors. The

reduction in selenium loadings will significantly improve the water quality around the steam electric power p lant discharge locations. Negative impacts from selenium on the environment and wildlife have been extensively documented in the literature (see Section 5.1 ). The r eductions in mercury loadings will improve human health as m ercury has been linked to decreased IQs in children when pregnant mothers have been exposed to mercury through fish consumption.

Under Options 3a and 3b, EPA estimates that arsenic (a carcinogen) and chromium VI loadings will reduce by 70 percent or more. Cadmium (a suspected carcinogen), c opper, lead,

mercury, total phosphorus, thallium, and zinc will be reduced by 20 percent or more. Nickel, total nitrogen, and selenium loadings will reduce by 10 percent or more.

Under Option 3, EPA estimates that arsenic (a carcinogen), cadmium (suspected carcinogen), chromium VI, manganese, selenium, and zinc loadings will reduce by 70 percent orSection 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-7 more. Boron, copper, mercury, nickel, and total nitrogen loadings will be reduced by 50 percent

or more

. EPA calculated lead and thallium loading reductions to be 38 and 23 percent, respectively.

Under Option 4a, EPA estimates that arsenic (a carcinogen), cadmium (suspected carcinogen), chromium VI, manganese, mercury, total nitrogen, selenium, total phosphorus, and

zinc loadings will reduce by 80 percent or more. Boron, copper, lead, nickel, TDS, and thallium loadings will be reduced by 55 percent or more . EPA calculated chlorides loading reductions to be 26 pe rcent.

Manganese and boron, while not generally considered toxic at levels seen in the aquatic environment, have the highest and third highest toxic weighted pound equivalents (TWPEs) (see

Section 3.2 ) under baseline conditions , respectively. Under the preferred options , the pollutant loadings for manganese and boron will decrease by 3 and 4 percent (under Option 3a), 4 and 22 percent (under Option 3b), 95 and 55 per cent (under Option 3), and 96 and 5 7 percent (under Option 4a) , respectively . Toxicity studies have reported boron- related effects occurring in fish and ducks; however, EPA has not set a National Recommended Water Quality Criteria (NRWQC) for boron [WHO, 1998]. Although manganese can be toxic to humans at high levels, it is also an essential nutrient required to maintain health [WHO, 2011]. Manganese can bioaccumulate in lower organisms, such as phytoplankton, algae, mollusks, and some fish, but not in higher organisms [ATSDR, 2008b]. EPA did not include boron and manganese in the EA model due to their low risk of adverse effects on the aquatic ecosystem and lack of partition

coefficient data needed for the model.

As discussed in Section 3.2 , nutrients (i.e., nitrogen and phosphorus) in excess quantities can adversely affect surface waters by causing oxygen -consuming algae blooms and creating

“dead zon es” where fish and shellfish cannot survive. EPA calculated that nitrogen loadings will reduce by 4.6 million pounds per year (15 percent) under Option 3a; 8.7 million pounds per year (29 percent) under Option 3b; 16.2 million pounds per year (53 percent) under Option 3; and

24.8 million pounds per year (82 percent) under Option 4a. EPA calculated that phosphorus loadings will reduce by 211,000 pounds per year (31 percent) under Option 3a; 231,000 pounds per year (34 percent) under Option 3b; 269,000 pounds per year (39 percent) under Option 3; and 496,000 pounds per year (73 percent) under Option 4a. The reduction in nutrients improves hypoxic areas (i.e., low oxygen surface waters) such as the Chesapeake Bay and the Gulf of Mexico (via reduced loadings to the Mississippi River Basin).

To protect freshwater fish and aquatic life, EPA recommends the following for chloride: criterion maximum concentration of 860 milligrams per liter (acute effects) and criterion continuous concentration of 230 milligrams per liter (chronic effects) [U.S. EPA, 2009d]. Exceeding these chloride levels in wastewater discharges can be harmful to animals and plants in

non- marine surface waters and can disrupt ecosystem structure. Under the preferred options, annual chloride loadings to surface waters will be reduced by 30.8 million pounds (under Option 3a), 209 million pounds (under Option 3b), 410 million pounds (under Option 3), and 434

million pounds (under Option 4a).

The pollutant parameter, TDS, is composed of dissolved solids such as chloride and

metals. Under the preferred options , EPA calculated that annual TDS loadings to surface watersSection 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-8 will be reduced by more than 400 million pounds (6 percent) under Option 3a, 1.5 billion pounds (21 percent) under Option 3b, 3 billion pounds (46 percent) under Option 3, and 4 billion pounds (57 percent) under Option 4a. This reduction is at least partially due to the reduction in total and dissolved metals discharged to receiving waters

.6-9 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-3 . Steam Electric Industry Pol lutant Reductions for Metals, Nutrients, Chlorides, and TDS Under Regulatory Options

Pollutant Reduction in Pollutant Loadings (lb/year) a

Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Arsenic 441

(1%) 411

(1%) 55,800

(70%) 56,000

(71%) 56,200

(71%) 68,000

(86%) 77,500

(98%) 78,000

(98%)

Boron 1,710,000

(3%) 27,500,000

(51%) 2,200,000

(4%) 11,900,000

(22%) 29,700,000

(55%) 31,100,000

(57%) 32,200,000

(59%) 53,100,000

(98%)

Cadmium 15,300

(48%) 15,500

(49%) 6,820

(21%) 12,500

(39%) 22,300

(70%) 27,500

(86%) 31,300

(98%) 31,400

(98%)

Chromium

VI 9.46

(<1%) 123

(1%) 9,050

(77%) 9,070

(77%) 9,170

(78%) 10,500

(89%) 11,500

(97%) 11,700

(99%)

Copper 2,780

(4%) 2,660

(4%) 32,600

(47%) 33,600

(48%) 35,300

(51%) 54,500

(78%) 68,800

(98%) 68,900

(99%)

Lead 538

(1%) 538

(1%) 23,900

(37%) 24,200

(38%) 24,500

(38%) 47,400

(74%) 63,800

(99%) 63,800

(99%)

Manganese 11,500,000

(79%) 13,400,000

(92%) 429,000

(3%) 5,200,000

(36%) 13,800,000

(95%) 14,000,000

(97%) 14,100,000

(97%) 14,400,000

(99%)

Mercury 759

(27%) 777

(28%) 1,010

(36%) 1,290

(46%) 1,790

(63%) 2,340

(83%) 2,780

(99%) 2,790

(99%)

Nickel 123,000

(43%) 123,000

(43%) 27,900

(10%) 72,500

(25%) 151,000

(53%) 228,000

(79%) 285,000

(99%) 285,000

(99%)

Selenium 103,000

(46%) 178,000

(79%) 30,000

(13%) 90,100

(40%) 208,000

(92%) 216,000

(96%) 222,000

(99%) 222,000

(99%)

Thallium 857

(1%) 1,990

(1%) 34,900

(21%) 35,600

(22%) 37,000

(23%) 110,000

(67%) 162,000

(99%) 163,000

(99%)

Zinc 193,000

(49%) 195,000

(50%) 92,000

(23%) 163,000

(41%) 287,000

(73%) 345,000

(88%) 390,000

(99%) 386,000

(98%)

Nitrogen,

total 1,520,000

(5%) 13,500,000

(44%) 4,550,000

(15%) 8,700,000

(29%) 16,200,000

(53%) 24,800,000

(82%) 29,300,000

(96%) 29,300,000

(96%)6-10 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-3 . Steam Electric Industry Pol lutant Reductions for Metals, Nutrients, Chlorides, and TDS Under Regulatory Options

Pollutant Reduction in Pollutant Loadings (lb/year) a

Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Phosphorus,

total 0

(0%) 0

(0%) 211,000

(31%) 231,000

(34%) 269,000

(39%) 496,000

(73%) 537,000

(79%) 553,000

(81%)

Chlorides 0

(0%) 371,000,000

(23%) 30,800,000

(2%) 209,000,000

(13%) 410,000,000

(25%) 434,000,000

(26%) 460,000,000

(28%) 1,620,000,000

(99%)

TDS 1,350,000,000

(19%) 2,860,000,000

(40%) 429,000,000

(6%) 1,510,000,000

(21%) 3,290,000,000

(46%) 4,040,000,000

(57%) 4,580,000,000

(64%) 7,010,000,000

(98%)

Source: ERG, 2013g.

Acronyms: TDS (Total Dissolved Solids); lb/yr (pounds per year).

a – All values are rounded to three significant figures.

b

– >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction; >60 percent reduction.6-11 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-4 . Steam Electric Industry Toxic Weighted Equivalent Pollutant Reductions for Metals, Nutrients, Chlorides, and TDS Under Regulatory Options

Pollutant Reduction in Pollutant Loadings (TWPE/yr) a

Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Arsenic 1,780

(1%) 1,660

(1%) 226,000

(71%) 226,000

(71%) 227,000

(71%) 275,000

(86%) 313,000

(98%) 315,000

(98%)

Boron 14,200

(3%) 230,000

(51%) 18,300

(4%) 99,100

(22%) 248,000

(55%) 260,000

(57%) 268,000

(59%) 443,000

(98%)

Cadmium 353,000

(48%) 358,000

(49%) 158,000

(21%) 288,000

(39%) 516,000

(70%) 636,000

(86%) 723,000

(98%) 725,000

(98%)

Chromium VI 4.89

(<1%) 63.7

(1%) 4,670

(77%) 4,690

(77%) 4,740

(78%) 5,420

(89%) 5,940

(98%) 6,020

(99%)

Copper 1,770

(4%) 1,690

(4%) 20,700

(47%) 21,300

(48%) 22,400

(50%) 34,600

(78%) 43,600

(98%) 43,700

(98%)

Lead 1,210

(1%) 1,210

(1%) 53,600

(37%) 54,100

(38%) 54,500

(38%) 106,000

(74%) 143,000

(99%) 143,000

(99%)

Manganese 808,000

(79%) 946,000

(93%) 30,200

(3%) 36,600

(4%) 973,000

(95%) 984,000

(96%) 992,000

(97%) 1,010,000

(99%)

Mercury 88,900

(27%) 91,000

(28%) 118,000

(36%) 151,000

(46%) 209,000

(63%) 274,000

(83%) 326,000

(99%) 327,000

(99%)

Nickel 13,400

(43%) 13,400

(43%) 3,040

(10%) 7,890

(25%) 16,400

(53%) 25,000

(80%) 31,100

(>99%) 31,100

(>99%)

Selenium 115,000

(46%) 200,000

(79%) 33,600

(13%) 101,000

(40%) 233,000

(92%) 242,000

(96%) 249,000

(99%) 249,000

(99%)

Thallium 881

(1%) 2,040

(1%) 35,900

(21%) 36,600

(22%) 38,000

(23%) 113,000

(67%) 167,000

(99%) 167,000

(99%)

Zinc 9,050

(49%) 9,150

(50%) 4,310

(23%) 7,630

(41%) 13,400

(73%) 16,200

(88%) 18,300

(99%) 18,100

(98%)

Nitrogen,

total N/A N/A N/A N/A N/A N/A N/A N/A6-12 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-4 . Steam Electric Industry Toxic Weighted Equivalent Pollutant Reductions for Metals, Nutrients, Chlorides, and TDS Under Regulatory Options

Pollutant Reduction in Pollutant Loadings (TWPE/yr) a

Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Phosphorus,

total N/A N/A N/A N/A N/A N/A N/A N/A

Chlorides 0

(0%) 9,030

(23%) 751

(2%) 5,090

(13%) 9,800

(25%) 10,600

(27%) 11,200

(28%) 39,500

(99%)

TDS N/A N/A N/A N/A N/A N/A N/A N/A

Source: ERG, 2013g.

Acronyms: TDS (Total Dissolved Solids); TWPE/yr (Toxic Weighted Pound Equivalents per year)

. N/A

– The TWPE/yr is not provided for total nitrogen, total phosphorus, and TDS because EPA has not established a toxic weighting factor (TWF) for these pollutants.

a – All values are rounded to three significant figures.

b

– >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction; >60 percent reduction.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-13 6.2 K EY 

### E NVIRONMENTAL 

### I MPROVEMENTS



### The preferred options will result in substantial improvements to water quality, wildlife,

and human health. EPA estimated that receiving water exceedances of the NRWQC will reduce under the preferred options by up to 29 percent (under Options 3a and 3b), 35 percent (under Option 3), and 55 percent (under Option 4a) . EPA estimate d that human exposures via fish consumption to pollutants with the potential to cause non- cancer health effects will decrease by up to 19 percent (under Option 3a), 21 percent (under Option 3b), 26 percent (u nder Option 3), and 47 percent (under Option 4a). EPA estimated that human exposures to pollutants that present a cancer risk will decrease by up to 40 percent (under Option 3a), 60 percent (under Options 3b and 3), and 80 percent (under Option 4a). EPA d etermined that these reductions will translate into lower exposure doses and a lower likelihood for adverse health effects to result.

Table 6-5 presents a summary of the key environmental improvements associated with the five regulatory options in the immediate receiving waters evaluated in the EA. Results for the preferred options are discussed in the sections following the table.

The receiving water model included a total of 297 immediate receiving waters (261 rivers and streams; 36 lakes, ponds, and reservoirs). Table 6-5 presents the number of receiving waters where negative impacts to water quality, wildlife, and human health are a concern due to pollutant discharges from steam electric power plants. For example, 147 of the 297 immediate

recei ving waters (49 percent) had concentrations of one or more pollutants that exceeded the criteria for human health (water and organism). The regulatory options evaluated for the proposed ELGs will improve receiving water quality and reduce impacts to wildlife and human receptors. Under Options 1 and 2, most of the water quality, wildlife, and human health exceedances will be reduced by between 0 to 20 percent of the immediate receiving waters. The number of immediate receiving waters with f reshwater acute NRWQC exceedances is reduced by 23 percent under Options 1 and 2. Under Options 3a and 3b, the number of immediate receiving waters with water quality exceedances is reduced by between 10 and 29 percent. The reduction in immediate receiving waters with wildl ife and human health benchmark exceedances under Options 3a and 3b fall s mostly into the 16 to 40 percent reduction range. Under Option 3, the number of immediate receiving waters with water quality exceedances is reduced by between 14 to 35 percent. The r eduction in immediate receiving waters with wildlife and human health benchmark exceedances under Option 3 fall s mostly into the 21 to 50 percent reduction range. The risk to recreational fishers (children) is reduced below benchmarks in 60 percent of the receiving waters that exceeded under baseline . Under Option 4a, most of the water quality, wildlife, and human health exceedances will be reduced by more than 35 percent of immediate receiving waters. Under Options 4 and 5, the number of immediate receivin g waters exceeding benchmarks is reduced by more than 50 percent for all benchmarks evaluated.6-14 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-5. Key Environmental Improvements Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria (Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Optio n
3a Option

3b Option

3 Option

4a Option

4 Option

5
Water Quality Results

Freshwater Acute NRWQC 31 10% 24
(23%) 24
(23%) 22
(29%) 22
(29%) 20
(35%) 14
(55%) 5
(84%) 5
(84%)

Freshwater Chronic NRWQC 67 23% 62
(7%) 56
(16%) 57
(15%) 56
(16%) 54
(19%) 39
(42%) 16
(76%) 16
(76%)

Human Health Water and Organism NRWQC 147 49% 147
(0%) 147
(0%) 127
(14%) 125
(15%) 120
(18%) 86
(41%) 48
(67%) 50
(66%) c

Human Health Organism

- only NRWQC 99 33% 99
(0%) 99
(0%) 89
(10%) 88
(11%) 85
(14%) 61
(38%) 28
(72%) 24
(76%)

Drinking Water

MCL 59 20% 58
(2%) 54
(8%) 53
(10%) 52
(12%) 51
(14%) 36
(39%) 5
(92%) 5
(92%)

Wildlife Results
Fish Ingestion NEHC

for Minks 99 33% 91
(8%) 83
(16%) 76
(23%) 75
(24%) 69
(30%) 49
(51%) 15
(85%) 15
(85%)
Fish Ingestion NEHC

for Eagles 129 43% 118
(9%) 110
(15%) 104
(19%) 103
(20%) 97
(25%) 69
(47%) 17
(87%) 17
(87%)

Human Health Results

— Non

- Cancer

Non

- cancer reference

dose for child (recreational) 124 42% 109
(12%) 106
(15%) 100
(19%) 98
(21%) 92
(26%) 66
(47%) 12
(90%) 10
(92%)

Non

- cancer reference

dose for adult (recreational) 128 43% 114
(11%) 109
(15%) 104
(19%) 102
(20%) 96
(25%) 69
(46%) 12
(91%) 10
(92%)

Non

- cancer reference

dose for child (subsistence) 196 66% 179
(9%) 173
(12%) 165
(16%) 163
(17%) 155
(21%) 111
(43%) 39
(80%) 33
(83%)

Non

- cancer reference

dose for adult (subsistence) 189 64% 170
(10%) 167
(12%) 159
(16%) 157
(17%) 149
(21%) 106
(44%) 35
(81%) 30
(84%)6-15 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-5. Key Environmental Improvements Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria (Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Optio n
3a Option

3b Option

3 Option

4a Option

4 Option

5

Human Health Results

— Cancer

Arsenic cancer risk for

child ( recreational) 5 2% 5
(0%) 5
(0%) 3
(40%) 2
(60%) 2
(60%) 1
(80%) 1
(80%) 1
(80%)

Arsenic cancer risk for adult (recreational) 12 4% 12
(0%) 12
(0%) 8
(33%) 8
(33%) 7
(42%) 5
(58%) 2
(83%) 2
(83%)

Arsenic cancer risk for child (subsistence) 9 3% 9
(0%) 9
(0%) 6
(33%) 6
(33%) 5
(44%) 4
(56%) 2
(78%) 2
(78%)

Arsenic cancer risk for adult (subsistence) 27 9% 25
(7%) 25
(7%) 20
(26%) 20
(26%) 19
(30%) 14
(48%) 3
(89%) 3
(93%)

Source: ERG, 2013h; ERG, 2013i; ERG, 2013l.

Acronyms: MCL ( Maximum C ontaminant L evel ); NEHC ( No E ffect H azard C oncentration ); NRWQC ( National Recommended Water Quality Criteria ).

a – The receiving water model included a total of 297 immediate receiving waters (261 rivers and streams; 36 lakes, ponds, and reservoirs) and evaluate d impacts

associated with the evaluat ed waste streams.

b

– >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction

.

c – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemica l precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system; therefore, for some immediate receiving waters the metal loadings will increase under Regulatory Option 5 compared to Regulatory Option 4, resulting in the percent reductions of exceedances being lower under Regulatory Option 5. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report (DCN SE01957) for further discussion of the regulatory option loadings.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-16 6.2.1 Improvements in Water Quality Under the Preferred Options

EPA estimated that reduced pollutant loadings to surface waters associated with the proposed Steam Electric ELGs will significantly improve water quality by reducing exceedances

of the NRWQC and maximum contaminant levels (MCLs) by 10 to 29 percent (under Options 3a and 3b), 14 to 35 percent (under Option 3), and 38 to 55 percent (under Option 4a). Improvements in water quality are driven by reductions in exceedances for arsenic, selenium, cadmium, and thallium.

EPA determined that the largest reductions in NRWQC exceedances are attributed to reduced loadings of cadmium and selenium under Options 3a, 3b, and 3 and reduced loadings of cadmium, selenium, arsenic, and thallium under Option 4a. Sublethal and lethal impacts from chronic exposure to cadmium (e.g., skeletal malformations and organ damage), selenium (e.g., fish kills, organ damage, and reproductive failure), arsenic (e.g., developmental abnormalities, behavioral impairments, and metabolic failure), and thallium (e.g., neurolo gical symptoms, gastrointestinal effects, and reproductive failure) are well documented in the literature following exposure to combustion wastewater [ATSDR, 2008a; Coughlan and Velte, 1989; Lemly, 1985b; Nagle et al., 2001; NRC, 2006; Rowe et al., 2002; U.S. EPA, 2009a; U.S. EPA, 2011f]. Due to the substantial reductions in these pollutants under the preferred options, EPA projects that aquatic organisms will be less susceptible to the adverse impacts described above.

EPA estimates that 33 to 49 percent (99 and 147 immediate receiving waters, respectively) of receiving waters currently exceed NRWQC for the protection of human health.

EPA estimated that these immediate receiving water exceedances, primarily driven by the discharge of total arsenic and total thallium, will decrease under the preferred options by 10 to 15 percent (under Options 3a and 3b), 14 to 18 percent (under Option 3 ), and 38 to 41 percent (under Option 4 a) . EPA determined that reductions in exposure to arsenic and thallium under the pref erred options will lower the number of immediate receiving waters that exceed NRWQC designed to protect public health. By reducing MCL exceedances by 10 percent (under Option 3a), 12 percent (under Option 3b), 14 percent (under Option 3 ), and 39 percent (under Option

4 a) , pollutant loading reductions under the preferred options will improve the quality of source water available to drinking water treatment plants downstream from steam electric power plants.

In addition to the reduction in NRWQC and MCL exce edances, EPA determined a quantifiable improvement in overall water quality to result from the preferred options. EPA calculated that, on average, receiving water concentrations of the 10 metals evaluated in the EA will be reduced by 22 to 36 percent (under Options 3a and 3b), 25 to 48 percent (under Option 3), and 47 to 60 percent (under Option 4a), considerably improving the water quality in the immediate receiving waters located downstream from steam electric power plants.

6.2.2 Reduced Threat to Wildlife Unde r the Preferred Option

In the EA, EPA evaluated multiple threats to wildlife, including exposure of aquatic organisms to contaminated sediments and receiving waters, bioaccumulation of metals in fish tissue, and negative impacts on wildlife that consume fish. The combination of both lethal and

sublethal effects (e.g., changes to morphology, behavior, and metabolism) of exposure to combustion wastewater can cause cascading effects through the food web.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-17 As discussed in Section 6.2.1 , EPA calculated that the number of immediate receiving

water s with the potential to pose an acute or chronic threat to wildlife will decrease u nder the proposed Steam Electric ELGs

, resulting in numerous unquantifiable improvements to wildlife populations and communities surrounding steam electric power plants (e.g., reduced impacts to population density and species diversity as discussed in Section 3.3 ). EPA then estimated that average fish tissue pollutant concentrations among the pollutants evaluated in the EA will decrease by as much as 33 percent under Option 3a, 36 percent under Option 3b, 48 percent under Option 3, and 60 percent under Option 4 a (in the case of selenium). EPA projects that these pollutant concentration reductions will result in a significant improvement in the health of fish populations and the quality of fish available for consumption by both humans and wildlife near steam electric power plants.

Studies and reports have highlighted the concern over the potential for bioaccumulative metals (e.g., selenium) commonly found in combustion wastewater to transfer from the aquatic environment and accumulate in terrestrial food webs surrounding steam electric power plants. EPA evaluated the threats to minks and eagles from consuming fish contaminated by combustion wastewater as an indication of the potential for pol lutants to bioaccumulate and impact higher order species in the food chain. EPA estimates that exceedances of the no effect hazard concentration (NEHC) for eagles and minks will decrease by 19 percent and 23 percent (under Option 3a), 20 percent and 24 per cent (under Option 3b), 25 percent and 30 percent (under Option 3) and by 47 percent and 51 percent (under Option 4 a)

, respectively, signifying that the preferred options will decrease the threat from bioaccumulative metals in the food chain.

6.2.3 Reduced Huma n Health Cancer Risk Under the Preferred Option

Under baseline conditions, EPA estimates that 27 immediate receiving water s (9 percent) would contain fish contaminated with inorganic arsenic that would present cancer risks above the

1- in -a- million threshol d for one or more of the cohorts evaluated. The preferred options reduce

the cancer risk for both recreational and subsistence fishers across all cohorts. EPA calculated that, under the preferred options, the number of immediate receiving waters whose fish exceed this cancer risk threshold will be reduced by between 26 to 40 percent (under Option 3a), 26 to 60 percent (under Option 3b), 30 to 60 percent (under Option 3), and 48 to 80 percent (under Option 4a), depending on the cohort.

6.2.4 Reduced Threat of Non

- Cancer Human Health Effects Under the Preferred Option

Reductions in pollutant loadings from the proposed ELGs will reduce the number of immediate receiving waters with contaminated fish that pose a potential threat to cause non

cancer health effects in humans . EPA estimates that the number of immediate receiving waters whose fish pose non- cancer health risks will be reduced by 16 to 19 percent (under Option 3a), 17 to 21 percent (under Option 3b), 21 to 26 percent (under Option 3), and 43 to 47 percent (under Option 4a), depending on the cohort. Chronic exposure to metals in combustion wastewater has the potential to reduce neurological and developmental functions and affect the circulatory, respiratory, and digestive systems of exposed populations. As discussed in Section

6.2.2 , EPA found that the pollutant concentrations in fish tissue will decrease under the preferred options, improving the qualit y of fish available to recreational and subsistence fishers andSection 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-18 subsequently lowering exposures to toxic metals and the potential for non- cancer health effects

to occur.

EPA determined that the potential for non- cancer health effects to occur are driven b y selenium, cadmium, mercury (as methylmercury), and to a lesser degree, thallium pollutant loadings. EPA calculated that the proposed ELGs will significantly reduce these potential effects by reducing the number of immediate receiving waters with exposure doses due to fish consumption that exceed the reference doses for these pollutants, as described below:

• 

### For selenium, these exceedances will decrease by up to 50 percent (under Option 3a), 52 percent (under Option 3b), 69 percent (under Option 3), and 77 percent (under Option 4a), depending on the cohort.

• 

### For cadmium, these exceedances will decrease by up to 38 percent (under Option 3a), 42 percent (under Option 3b), 54 percent (under Option 3), and 69 percent (under Option 4a), depending on the cohort.

• 

### For methylmercury, these exceedances will decrease by up to 21 percent (under Option 3a), 22 percent (under Option 3b), 29 percent (under Option 3), and 49 percent (under Option 4a), depending on the cohort.

• 

### For thallium, these exceedances will decrease by up to 14 percent (under Options 3a and 3b), 18 percent (under Option 3), and 43 percent (under Option 4a), depending on

the cohort.

EPA determined that the reduced loadings for the pollutants above will reduce the potential threat for non- cancer health ef fects (e.g., nausea, abdominal pain, sleep disorders, muscular problems, and cardiovascular disease) in humans that consume contaminated fish from these receiving waters.

Although the EA did not directly assess the potential non- cancer health effects pos ed by lead, 40 

### the proposed ELGs will lower the total loadings of lead to the environment, thus reducing the potential threat of hypertension, coronary heart disease, and impaired cognitive function in exposed populations. For children in particular, lead ex posure can cause additional negative impacts, such as hyperactivity, behavioral and attention difficulties, delayed mental development, and motor and perceptual skill deficits. The benefits to children from the reduced discharge of lead are discussed in th e Benefits and Cost Analysis.

6.3 P OLLUTANT 

### -S PECIFIC 

### I MPROVEMENTS



### In the above analyses, EPA identified several key pollutants (i.e., arsenic, mercury, selenium, cadmium, and thallium) as the primary drivers for the improvements in water quality, wildlife, and human health attributed to the preferred options. This section highlights the pollutant- specific environmental improvements calculated to result from Options 3a, 3b, 3, and

4a. It also presents a qualitative discussion of the loading reductions under the preferred options

40 Currently, there is no reference dose for lead

— there is no safe level for ingestion of lead (see EPA’s Integrated Risk Information System (IRIS) website: http://www.epa.gov/IRIS/).Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-19 for the 10 metals included in the EA model and other pollutants with high loading impacts on receiving waters (i.e., boron, manganese, nutrients, TDS, and chlorides).

6.3.1 Arsenic

Arsenic is a toxic and carcinogenic metal. EPA’s baseline analysis of the evaluated waste streams identified arsenic as a key pollutant causing negative impacts to the surface water, including receiving water exceedances of water quality standards, threats to mink who consume contaminated fish, risk of cancer and non- cancer health effects in humans that consume contaminated fish. The preferred options will reduce the number of immediate receiving waters exceeding acute and chronic NRWQC from seven to four under Options 3a and 3b, three under Option 3, and two under Option 4a . This reduction in arsenic discharged to receiving waters will reduce negative effects on aquatic organisms, such as liver tissue death, developmental abnormalities, behavioral impairments, metabolic failure, growth reduction, and appetite loss [NRC, 2006; Rowe et al., 2002; U.S. EPA, 2011f].

Arsenic, along with mercury and selenium, can readily bioaccumulate in exposed biota (e.g., fish). The bioaccumulation of these pollutants is of particular concern due to the potential for impacting higher t rophic levels, local terrestrial environments, and transient species, in addition to the aquatic organisms directly exposed to the wastewater. Aquatic systems with long residence times and potential contamination with bioaccumulative pollutants often exper ience persistent environmental effects after receiving combustion wastewater. The preferred options

will reduce the bioaccumulation of arsenic in the food web and reduce the number of immediate receiving waters exceeding NEHCs for minks from two to one under Options 3a, 3b, 3, and 4a.

Non

- cancer human health effects from arsenic exposure include cardiovascular, pulmonary, immunological, neurological, and endocrine (e.g., diabetes) effects . Arsenic has been linked to cancer of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate [U.S. EPA, 2001]. The preferred options will reduce human exposure to arsenic through fish consumption and thus lower the potential for exposed populations to develop arsenic- related cancer and non

cancer health effects. Table 6-6 presents the key environmental improvements as a result of reduced arsenic discharges under the regulatory options.6-20 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-6. Key Environmental Improvements for Arsenic Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria (Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5
Water Quality Results

Freshwater Acute NRWQC 6 2% 6
(0%) 6
(0%) 4
(33%) 3
(50%) 3
(50%) 2
(67%) 1
(83%) 1
(83%)

Freshwater Chronic
NRWQC 7 2% 7
(0%) 7
(0%) 4
(43%) 4
(43%) 3
(57%) 2
(71%) 2
(71%) 2
(71%)

Human Health Water and Organism NRWQC 147 49% 147
(0%) 147
(0%) 125
(15%) 123
(16%) 120
(18%) 87
(41%) 48
(67%) 50
(66%) c

Human Health Organism

- only NRWQC 96 32% 96
(0%) 96
(0%) 84
(13%) 84
(13%) 82
(15%) 60
(38%) 28
(71%) 24
(75%)

Drinking Water

MCL 19 6% 19
(0%) 19
(0%) 13
(32%) 13
(32%) 12
(37%) 9
(53%) 2
(89%) 2
(89%)

Wildlife Results
Fish Ingestion NEHC

for Minks 2 1% 2
(0%) 2
(0%) 1
(50%) 1
(50%) 1
(50%) 1
(50%) 0
(100%) 0
(100%)
Fish Ingestion NEHC for Eagles 0 0% 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A)

Human Health Results

— Non

- Cancer

Non

- cancer reference

dose for child (recreational) 0 0% 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A)

Non

- cancer reference

dose for adult (recreational) 0 0% 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A) 0
(N/A)

Non

- cancer reference

dose for child (subsistence) 3 1% 3
(0%) 3
(0%) 2
(33%) 2
(33%) 2
(33%) 1
(67%) 1
(67%) 1
(67%)

Non

- cancer reference

dose for adult (subsistence) 2 1% 2
(0%) 2
(0%) 1
(50%) 1
(50%) 1
(50%) 1
(50%) 0
(100%) 0
(100%)6-21 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-6. Key Environmental Improvements for Arsenic Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria (Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Human Health Results

— Cancer

Arsenic cancer risk for child (recreational) 5 2% 5
(0%) 5
(0%) 3
(40%) 2
(60%) 2
(60%) 1
(80%) 1
(80%) 1
(80%)

Arsenic cancer risk for adult (recreational) 12 4% 12
(0%) 12
(0%) 8
(33%) 8
(33%) 7
(42%) 5
(58%) 2
(83%) 2
(83%)

Arsenic cancer risk for child (subsistence) 9 3% 9
(0%) 9
(0%) 6
(33%) 6
(33%) 5
(44%) 4
(56%) 2
(78%) 2
(78%)

Arsenic cancer risk for adult (subsistence) 27 9% 25
(7%) 25
(7%) 20
(26%) 20
(26%) 19
(30%) 14
(48%) 3
(89%) 2
(93%)

Source: ERG, 2013h; ERG, 2013i; ERG, 2013l.

Acronyms: MCL (Maximum C ontaminant L evel ); NEHC (No Effect Hazard C oncentration ); N/A ( Not Applicable, no exceedances at baseline conditions to compare option results ); NRWQC ( National Recommended Water Quality Criteria ).

a – The receiving water model included a total of 297 immediate receiving waters (261 rivers and stre ams; 36 lakes, ponds, and reservoirs).

b

– >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction

.

c – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams t ogether in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system; therefore, for some immediate receiving waters the metal loadings will increase under Regulatory Option 5 compared to Regulatory Option 4, resulting in the percent reductions of exceedances being lower under Regulatory Option 5. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report (DCN SE01957) for further discussion of the regulatory option loadings.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-22 6.3.2 Mercury

As discussed in Section 5.3.2 , estimated fish tissue concentrations for mercury (and selenium) exceed levels that have the potential to cause reduced reproductive success in exposed mink and eagle populations. EPA estimated that the preferred options will reduce the number of

immediate receiving waters with fish tissue concentrations that exceed the mercury NEHC for eagles and minks by 19 and 24 percent (under Option 3a), 20 and 26 percent (under Option 3b), 26 and 33 percent (under Option 3), and 47 and 52 percent (under Option 4a), respectively. These reductions are representative of the potential improvement in exposure to mercury above effects thresholds in other wildlife that consume fish from these receiving waters.

People in the United States are mainly exposed to methylmercury through the ingestion of contaminated fish and shellfish. For fetuses, infants, and children, the primary health effect of methylmercury is impaired neurological development. Methylmercury exposure in the womb, which can result from a mother’s consumption of fish and shellfish that contain methylmercury, can adversely affect a baby’s growing brain and nervous system. Impacts on cognitive thinking, memory, attention, language, and fine motor and visual spatial skills have been seen in childr en who were exposed to methylmercury in the womb.

Under baseline pollutant loadings, EPA estimates that fish methylmercury concentrations pose a non-cancer threat to subsistence fishers in approximately 62 to 65 percent of immediate receiving water s. For recreational fishers, fish methylmercury concentrations pose a non- cancer threat in approximately 40 to 42 percent of the immediate receiving water s. EPA calculated that fish tissue concentrations of methylmercury will decrease and , as a result , the number of immediate receiving waters with exposure doses from fish consumption that exceed the methylmercury reference dose will be reduced by up to 21 percent (under Option 3a), 22 percent (under Option 3b), 29 percent (under Option 3), and 49 percent (under Option 4a) . Several of the

steam electric plants addressed by this ELG discharge to receiving waters that are under a fish advisory for mercury (see Section 3.4.2 ). The preferred options result in reduced mercury loadings to receiving waters with fish advisories for mercury and for impaired waters (see

Section 6.4 ). Table 6-7 presents the key environmental improvements as a result of reduced mercury discharges under the reg ulatory options.6-23 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-7 . Key Environmental Improvements for Mercury Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria
(Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Water Quality Results

Freshwater Acute NRWQC 2 1% 1

(50%) 1

(50%) 1

(50%) 0

(100%) 0

(100%) 0

(100%) 0

(100%) 0

(100%)

Freshwater Chronic

NRWQC 2 1% 1

(50%) 1

(50%) 1

(50%) 0

(100%) 0

(100%) 0

(100%) 0

(100%) 0

(100%)

Human Health Water and Organism NRWQC N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Human Health Organism

- only NRWQC N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Drinking Water

MCL 0 0% 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A)

Wildlife Results

Fish Ingestion NEHC

for Minks 96 32% 78

(19%) 78

(19%) 73

(24%) 71

(26%) 64

(33%) 46

(52%) 6
(94%) 6
(94%)

Fish Ingestion NEHC for Eagles 127 43% 109

(14%) 107

(16%) 103

(19%) 101

(20%) 94

(26%) 67

(47%) 10

(92%) 10

(92%)

Human Health Results

— Non

- Cancer

Non

- cancer reference

dose for child (recreational) 119 40% 101

(15%) 99

(17%) 94

(21%) 93

(22%) 85

(29%) 61

(49%) 10

(92%) 8

(93%)

Non

- cancer reference

dose for adult (recreational) 124 42% 106

(15%) 103

(17%) 99

(20%) 98

(21%) 90

(27%) 64

(48%) 10

(92%) 8

(94%)6-24 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-7 . Key Environmental Improvements for Mercury Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria
(Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Non

- cancer reference

dose for child (subsistence) 193 65% 175

(9%) 168

(13%) 162

(16%) 160

(17%) 150

(22%) 107

(45%) 33

(83%) 27

(86%)

Non

- cancer reference

dose for adult (subsistence) 185 62% 166

(10%) 161

(13%) 154

(17%) 152

(18%) 143

(23%) 102

(45%) 30

(84%) 23

(88%)

Source: ERG, 2013h; ERG, 2013i; ERG, 2013l.

Acronyms: MCL (Maximum Contaminant L evel ); N/A ( Not A pplicable

, no benchmark for comparison ); NEHC (No Effect Hazard C oncentration); NRWQC ( National Recommended Water Quality Criteria ).

a – The receiving water model included a total of 297 immediate receiving waters (261 rivers and streams; 36 lakes, ponds, and reservoirs).

b

– >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction

.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-25 6.3.3 Selenium

Selenium was one of the primary pollutants identified in the literature and by EPA as causing documented environmental impacts to fish and wildlife. EPA reviewed over 100 case studies on selenium discharges and their environmental impacts, and found that 80 case studies showed damages to surface water quality and 43 case studies showed damages to ground water quality. 41 

### For more information on the case studies, refer to Section 3.5

.

Studies have shown that selenium can bioaccumulate to toxic levels in organisms inhabiting aquatic environments with low selenium concentrations. In surface waters, selenium

can accumulate and biomagnify to toxic levels in aquatic organisms and pose a lethal threat to fish at the top of the trophic structure [Lemly, 1985a]. Studies concluded that elevated selenium concentrations were likely the primary factor contributing to fish kills, decreasing population density, and community diversity in lakes and reservoirs that receive combustion wastewater [Coughlan and Velte, 1989; Crutchfield and Ferguson, 2000a; Crutchfield, 2000b; Cumbie and Van Horn, 1978]. In addition, the bioaccumulative properties of selenium (and other combustion pollutants) can lead to long recovery times associated with many of the ecological impacts [Rowe et al., 2002; NRC, 2006]. EPA estimates that immediate receiving water concentrations of

total selenium due to combusti on wastewater discharges will decrease by 33 percent on average (under Option 3a), 36 percent on average (under Option 3b), 48 percent on average (under Option 3), and 60 percent on average (under Option 4 a) . This will result in decreased concentrations of selenium that bioaccumulate or persist in the aquatic environment. The preferred options will result in a 38 percent reduction (under Option 3a), 40 percent reduction (under Option 3b), 55 percent reduction (under Option 3), and 67 percent reduction (unde r Option 4a) in the number of immediate receiving waters exceeding chronic aquatic life NRWQC and a 50 percent reduction (under Option 3a), 55 percent reduction (Option 3b), 75 percent reduction (Option 3), and 80 percent reduction (Option 4a) in the numbe r of immediate receiving waters exceeding a drinking water MCL.

The sublethal effects of selenium include negative impacts to growth, reproduction, and survival of susceptible organisms, including various fish and amphibian species. In surface

waters conta minated with combustion wastewater, scientists observed that these fish and amphibian species developed sublethal symptoms such as accumulation of selenium in tissue causing histopathological effects and in the blood, decreased growth, changes in weight, abnormal morphology, and reduced hatching success [Coughlan and Velte, 1989; Sager and Colfield, 1984; Sorensen et al., 1982, 1983, 1988; Sorensen and Bauer, 1984a; Sorensen et al., 1984b]. Selenium accumulates most significantly in the liver and reproductive tissues in the majority of species and causes negative reproduction and histopathological impacts [Baumann and Gillespie, 1986]. As an assessment of the potential for sublethal effects to occur in fish, EPA compared modeled and estimated fish tissue con centrations of selenium to selenium concentrations where a negative impact occurred as documented in literature [ Baumann and Gillespie, 1986]. EPA evaluated fish for two trophic levels:

• 

### Trophic level 4 (T4), largemouth bass (Micropterus salmoides)

.

41 Note that one plant may impact both surface water and ground water.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-26 • 

### Trophic level 3 (T3), bluegill (Lepomis macrochirus). Female bluegill population accumulated selenium concentrations 1,000 times greater than in the water from which the fish were collected [Baumann and Gillespie, 1986].

Under baseline conditions, EPA estimates that T4 fish will exhibit selenium concentrations above levels documented in the literature to cause negative reproductive and histopathological effects in 18 percent (54 ) of immediate receiving waters. EPA estimates that T3 fish will exceed these negative effects thresholds in 13 percent (40) of immediate receiving

water s. Table 6-8 presents the percent reduction in the number of immediate receiving water s with seleniu m fish tissue concentrations above the literature values for each regulatory option.

EPA determined that selenium concentrations in T4 fish will improve to below the negative effects concentrations documented in the literature in 26 percent (under Option 3a), 28

percent (under Option 3b), 37 percent (under Option 3), and 52 percent (under Option 4a) of immediate receiving waters whose fish currently exceed those thresholds. Similarly, EPA

determined that selenium concentrations in T3 fish will improve to be low the negative effects concentrations documented in the literature in 44 percent (under Option 3a), 48 percent (under Option 3b), 64 percent (under Option 3), and 73 percent (under Option 4a) of immediate receiving waters whose fish currently exceed those thresholds.

The reduction in selenium loadings and reduced bioaccumulation in the environment under the preferred options will reduce the number of immediate receiving waters with fish tissue concentrations exceeding the NEHC for selenium for eagles and minks by 28 and 29 percent (under Option 3a), 30 and 31 percent (under Option 3b), 41 and 42 percent (under Option 3), and 57 and 56 percent (under Option 4a), respectively. These reductions are representative of the likely improvements to selenium exposure above effects thresholds in other wildlife that consume fish from these receiving waters and are indications of the potential improvements in bioaccumulation of metals in the broader food web near steam electric power plants.

EPA estimates that intake doses resultingfrom fish selenium concentrations that pose a noncancer threat to recreational fishers and subsistence fishers will decrease in up to 50 and 32 percent of immediate receiving waters (under Option 3a), 52 and 34 percent of immediate receiving waters (under Option 3b), 69 and 45 percent of immediate receiving waters (under Option 3), and 88 and 76 percent of immediate receiving waters (under O ption 4a), respectively. This reduced the threat for developing non- cancer health effects associated with selenium such as pulmonary edema and lesions of the lung; cardiovascular effects such as tachycardia; gastrointestinal effects including nausea, vomiting, diarrhea, and abdominal pain; effects on the liver; and neurological effects such as aches, irritability, chills, and tremors [U.S. EPA, 2000b].

Table 6-9 present s the key environmental improvements as a result of reduced selenium discharges under the regulatory options. Selenium is known to cause fish deformities at high
levels, such as these from Belews Lake, NC.6-27 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-8. Comparison of Estimated Selenium Concentrations in Fish to Documented Literature Fish Impacts

Wildlife

Affected/ Trophic

Level Documented Impact

Selenium

Concentration b

(μg/g) Immediate Receiving Waters Exceeding

Literature Value Under

Baseline Conditions a,c Number of Immediate Receiving Waters Still Impacted Under Regulatory Options
(Percent Reduction from Baselin e Conditions) a

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5
Largemouth

bass/T4 Female carcass = 2.86 53 18% 52
(2%) 39
(26%) 40
(25%) 39
(26%) 34
(36%) 26
(51%) 16
(70%) 21
(60%) d

Male carcass = 2.63 54 18% 52
(4%) 39
(28%) 40
(26%) 39
(28%) 34
(37%) 26
(52%) 16
(70%) 21
(61%) d

Bluegill/T3 Female carcass = 2.74 40 13% 35
(13%) 23
(43%) 23
(43%) 21
(48%) 15
(63%) 11
(73%) 8
(80%) 8
(80%)

Male carcass = 4.64 36 12% 30
(17%) 20
(44%) 20
(44%) 19
(47%) 13
(64%) 10
(72%) 6
(83%) 6
(83%)

Source: Baumann and Gillespie, 1986; ERG, 2013h; ERG, 2013i; ERG, 2013j; ERG, 2013l

. Acronym: μg/g (m icrograms per gram )

Note: A total of 297 immediate receiving waters (261 rivers and streams; 36 lakes, ponds, and reservoirs) were included in th e wildlife model.

a – These values are the sum and percentage of rivers, streams, lakes, ponds, and reservoirs impacted. >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction

. b

– The study concluded that the selenium accumulating in the fish can have negative reproductive and histopathological effects.

c – This represents the number of unique immediate receiving waters that exceeded a standard.

d

– Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemica l precipitation plus biological treatment system which may result in leachate switching receiving waters to be discharged in the same receiving water as FGD. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system and is discharged to the original designated rece iving wa ter; therefore, due to changes in receiving waters between Regulatory Options 4 and 5, the metal loadings at an immediate receiving water level may increase under Regulatory Option 5 compared to Regulatory Option 4, resulting in the percent reductions of exceedances being lower under Regulatory Option 5.6-28 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-9 . Key Environmental Improvements for Selenium Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria
(Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Water Quality Results

Freshwater Acute NRWQC N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Freshwater Chronic

NRWQC 42 14% 38

(10%) 26

(38%) 26

(38%) 25

(40%) 19

(55%) 14

(67%) 11

(74%) 10

(76%)

Human Health Water and Organism NRWQC 13 4% 10

(23%) 7

(46%) 6
(54%) 6
(54%) 3

(77%) 2

(85%) 2

(85%) 2

(85%)

Human Health Organism

- only NRWQC 0 0% 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A) 0

(N/A)

Drinking Water

MCL 20 7% 17

(15%) 10

(50%) 10

(50%) 9

(55%) 5

(75%) 4

(80%) 3

(85%) 3

(85%)

Wildlife Results

Fish Ingestion NEHC

for Minks 48 16% 47

(2%) 34

(29%) 34

(29%) 33

(31%) 28

(42%) 21

(56%) 13

(73%) 13

(73%)

Fish Ingestion NEHC for Eagles 46 15% 45

(2%) 32

(30%) 33

(28%) 32

(30%) 27

(41%) 20

(57%) 12

(74%) 12

(74%)

Human Health Results

— Non

- Cancer

Non

- cancer reference

dose for child (recreational) 25 8% 24

(4%) 14

(44%) 13

(48%) 12

(52%) 8

(68%) 6
(76%) 3

(88%) 3

(88%)

Non

- cancer reference

dose for adult (recreational) 26 9% 25

(4%) 14

(46%) 13

(50%) 13

(50%) 8

(69%) 6
(77%) 3

(88%) 3

(88%)6-29 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-9 . Key Environmental Improvements for Selenium Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria
(Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Non

- cancer reference

dose for child (subsistence) 45 15% 44

(2%) 30

(33%) 31

(31%) 30

(33%) 25

(44%) 19

(58%) 11

(76%) 13

(71%) c

Non

- cancer reference

dose for adult (subsistence) 44 15% 42

(5%) 29

(34%) 30

(32%) 29

(34%) 24

(45%) 18

(59%) 11

(75%) 13

(70%) c

Source: ERG, 2013h; ERG, 2013i; ERG, 2013l.

Acronyms: MCL ( Maximum C ontaminant L evel ); N/A (Not A pplicable

, no benchmark for comparison ); NEHC ( No Effect Hazard C oncentration); NRWQC ( National Recommended Water Quality Criteria ).

a – The receiving water model include d a total of 297 immediate receiving water s (261 rivers and streams; 36 lakes , ponds, and reservoirs).

b

– >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduc tion; >60 percent reduction

.

c – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemica l precipitation plus biological treatment system which may result in leachate switching receiving waters to be discharged in the same receiving water as FGD. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system and is discharged to the original designated receiving water; therefore, due to changes in receiving waters between Reg ulatory Options 4 and 5, the metal loadings at an immediate receiving water level may increase under Regulatory Option 5 compared to Regulatory Option 4, resulting in the percent reductions of exceedances being lower under Regulatory Option 5.Se ction 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-30 6.3.4 Cadmium

At baseline conditions, cadmium had the s econd largest toxic -weighted pollutant discharges from the steam electric industry (see Section 3.2 ). Cadmium is a toxic metal that is known to disrupt development in wildlife, resulting in fetal malformations and other effects. Studies of steam electric discharges have demonstrated that cadmium and other combustion wastewater metals can be lethal to fish and amphibian eggs [Birge, 1978]. In addition, it has been

li nked to impacts on mammals as well. For example, in a study of raccoons living in close proximity to a steam electric power plant ash pond, cadmium buildup was found in the raccoons’ kidneys at elevated levels [Burger et al., 2002]. EPA determined that the preferred options will reduce impacts to both aquatic life and wildlife by decreasing the number of immediate receiving

waters that exceed acute and chronic NRWQC by up to 27 percent (under Option 3a and 3b), 37

percent (under Option 3 ), and 53 percent (under Option 4 a) . The number of immediate receiving

waters with fish tissue concentrations that exceed NEHCs for minks and eagles will decrease by up to 44 percent (under Options 3a and 3b), 58 percent (under Option 3 ), and 67 percent (under Option 4 a) . EP A determined that the preferred options will reduce the number of immediate receiving waters with intake doses from fish that have the potential to cause non- cancer health effects by 36 to 38 percent (under Option 3a), 38 to 42 percent (under Option 3b), 50 to 54

percent (under Option 3 ), and 64 to 69 percent (under Option 4 a) , depending on the cohort. In humans, cadmium-related health effects can result from exposure via multiple pathways, with the nature and severity of the effects depending on the exposure doses. Table 6-10 presents the key environmental improvements as a result of reduced cadmium discharges under the regulatory options.6-31 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-10. Key Environmental Improvements for Cadmium Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria
(Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Water Quality Results

Freshwater Acute NRWQC 30 10% 23

(23%) 23

(23%) 22

(27%) 22

(27%) 19

(37%) 14

(53%) 5

(83%) 5

(83%)

Freshwater Chronic

NRWQC 65 22% 55

(15%) 54

(17%) 55

(15%) 54

(17%) 51

(22%) 37

(43%) 13

(80%) 13

(80%)

Human Health Water and Organism NRWQC N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Human Health Organism

- only NRWQC N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Drinking Water

MCL 22 7% 14

(36%) 14

(36%) 13

(41%) 13

(41%) 10

(55%) 7

(68%) 3

(86%) 2

(91%)

Wildlife Results

Fish Ingestion NEHC

for Minks 12 4% 9

(25%) 8

(33%) 7

(42%) 7

(42%) 5

(58%) 4

(67%) 2

(83%) 2

(83%)

Fish Ingestion NEHC for Eagles 9 3% 7

(22%) 7

(22%) 5

(44%) 5

(44%) 4

(56%) 3

(67%) 2

(78%) 2

(78%)

Human Health Results

— Non

- Cancer

Non

- cancer reference

dose for child (recreational) 13 4% 9

(31%) 9

(31%) 8

(38%) 8

(38%) 6
(54%) 4

(69%) 2

(85%) 2

(85%)

Non

- cancer reference

dose for adult (recreational) 13 4% 10

(23%) 10

(23%) 8

(38%) 8

(38%) 6
(54%) 4

(69%) 2

(85%) 2

(85%)6-32 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-10. Key Environmental Improvements for Cadmium Under the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria
(Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Non

- cancer reference

dose for child (subsistence) 28 9% 20

(29%) 19

(32%) 18

(36%) 17

(39%) 14

(50%) 10

(64%) 3

(89%) 3

(89%)

Non

- cancer reference

dose for adult (subsistence) 26 9% 18

(31%) 17

(35%) 16

( 38 %) 15

( 42 %) 12

( 54 %) 9

(65%) 3

(8 8 %) 3

(8 8 %)

Source: ERG, 2013h; ERG, 2013i; ERG, 2013l.

Acronyms: MCL (Maximum Contaminant L evel ); N/A ( Not A pplicable

, no benchmark for comparison ); NEHC (No Effect Hazard C oncentration); NRWQC ( National Recommended Water Quality Criteria ).

a – The receiving water model include d a total of 297 immediate receiving water s (261 rivers and streams; 36 lakes , ponds, and reserv oirs).

b

– >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction

.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-33 6.3.5 Thallium

Thallium is a toxic metal. As noted in Section 6.2.2 , impacts from elevated thallium exposures include neurological symptoms (e.g., weakness, sleep disorders, muscular problems), alopecia (i.e., loss of hair from the head and body), and gastrointestinal effects (e.g., diarrhea and vomiting). Long -term exposures at levels above the MCL may lead to changes in blood chemistry; damage to liver, kidney, and intestinal and testicular tissues; and hair loss. Thallium exposure can also lead to reproductive and developmental damage [U.S. EPA, 2009a]. EPA

estimates that the number of immediate receiving waters exceeding human health NRWQC and

MCLs will reduce by 7 to 13 percent (under Option 3a), 9 to 15 percent (under Option 3b), 11 to 18 percent (under Option 3 ), and 38 to 44 percent (under Option 4 a) . The preferred options will also reduce the number of immediate receiving waters with intake doses from fish that have the potential to cause non- cancer health effects in humans by 12 to 14 percent (under Options 3a and 3b), 16 to 18 percent (under Option 3 ), and 41 to 43 percent (under Option 4 a) , depending on the

cohort. Table 6-11 presents the key environmental improvements as a result of reduced thallium discharges under the regulatory options.6-34 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-11. Key Environmental Improvements for Thallium U nder the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria
(Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Water Quality Results

Freshwater Acute NRWQC N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Freshwater Chronic

NRWQC N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Human Health Water and Organism NRWQC 82 28% 82

(0%) 79

(4%) 71

(13%) 70

(15%) 67

(18%) 46

(44%) 13

(84%) 14

(83%) c

Human Health Organism

- only NRWQC 74 25% 73

(1%) 71

(4%) 65

(12%) 65

(12%) 62

(16%) 43

(42%) 10

(86%) 7

(91%)

Drinking Water MCL 55 19% 55

(0%) 52

(5%) 51

(7%) 50

(9%) 49

(11%) 34

(38%) 4

(93%) 4

(93%)

Wildlife Results

Fish Ingestion NEHC

for Minks N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

F ish Ingestion NEHC

for Eagles N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

Human Health Results

— Non

- Cancer

Non

- cancer reference

dose for child (recreational) 74 25% 73

(1%) 71

(4%) 65

(12%) 65

(12%) 62

(16%) 43

(42%) 10

(86%) 7

(91%)

Non

- cancer reference

dose for adult (recreational) 75 25% 74

(1%) 72

(4%) 66
(12%) 66
(12%) 63

(16%) 44

(41%) 10

(87%) 7

(91%)6-35 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-11. Key Environmental Improvements for Thallium U nder the Regulatory Options

Evaluation Criteria Modeled Immediate Receiving Waters Exceeding Criteria

Under Baseline Conditions a Number of Immediate Receiving Water Exceeding Criteria
(Percent Reduction from Baseline Conditions) Under the Regulatory Options b

Number Percentage Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Non

- cancer reference

dose for child (subsistence) 118 40% 116

(2%) 111

(6%) 102

(14%) 101

(14%) 97

(18%) 67

(43%) 24

(80%) 22

(81%)

Non

- cancer reference

dose for adult (subsistence) 109 37% 107

(2%) 104

(5%) 96

(12%) 96

(12%) 92

(16%) 64

(41%) 19

(83%) 18

(83%)

Source: ERG, 2013h; ERG, 2013i; ERG, 2013l.

Acronyms: MCL ( Maximum C ontaminant L evel ); N/A ( Not A pplicable

, no benchmark for comparison ); NEHC ( No E ffect H azard C oncentration); NRWQC ( National Recommended Water Quality Criteria ).

a – The receiving water model include d a total of 297 immediate receiving water s (261 rivers and streams; 36 lakes, ponds, and reservoirs).

b

– >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction

.

c – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemica l precipitation plus biological treatment system which may result in leachate switching receiving waters to be discharged in the same receiving water as FGD. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system and is discharged to the original designated rece iv ing water; therefore, due to changes in receiving waters between Regulatory Options 4 and 5, the metal loadings at an immediate receiving water level may increase under Regulatory Option 5 compared to Regulatory Option 4, resulting in the percent reductions of exceedances being lower under Regulatory Option 5.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-36 6.4 I MPROVEMENTS TO 

### S ENSITIVE 

### E NVIRONMENTS AND 

### W ATERSHEDS



### As discussed in Sections 3.2 and 3.4 , EPA evaluated pollutant discharges to sensitive environments (i.e., impaired waters, threatened and endangered species, and fish consumption advisory waters) and sensitive watersheds (the Great Lakes and Chesapeake Bay) to assess the potential for steam electric power plants to contribute to existing impairments or advisories and assess the pot ential for discharges of the evaluated waste streams to cause increased stress on threatened and endangered species. This section presents EPA’s estimated pollutant loading

reductions under the eight regulatory options to the evaluated sensitive environmen ts. EPA

determined that the proposed ELGs will decrease pollutant loadings to sensitive environments which will assist in the recovery of impaired waters; reduce the bioaccumulation of metals in fish, thereby reducing the number of fish advisories; and red uce stress on threatened and endangered species and sensitive watersheds such as Chesapeake Bay and the Great Lakes.

6.4.1 Impaired Waters

EPA determined that 78 of the steam electric power plants discharge directly into a 303(d) listed water body designated as impaired for one or more pollutants found in the evaluated waste streams. Mercury (52 immediate receiving water s), nutrients (30 immediate receiving water s), and phosphorus (16 immediate receiving waters) were the most frequently identified impairment cate gories among the surface waters that directly receive the evaluated

waste streams

. Table 6- 12 presents the loading reductions to impaired waters by imp airment category as a result of the regulatory options.

Under the preferred options, EPA calculated mercury loadings to waters designated as impaired for mercury will be reduced by 31 percent (under Options 3a and 3b), 48 percent (under Option 3 ), and 71 p ercent (under Option 4 a) . EPA also calculated that total metal loadings to waters designated as impaired for metals other than mercury will be reduced by 19 percent (over 37,000 pounds) under Option 3a, 29 percent (over 55,000 pounds) under Option 3b, 44 p ercent (over 85,000 pounds) under Option 3, and by 79 percent (152,000 pounds) under Option 4a. Phosphorus loadings to water designated as impaired for phosphorus are estimated to reduce by almost 17,000 pounds (under Options 3a and 3b), almost 20,000 pounds (under Option 3 ), and

almost 35,000 pounds (under Option 4 a) . EPA determined 9 percent (30 immediate receiving waters) of surface waters receiving the evaluated waste streams are designated as impaired for the general category of nutrients. EPA estimated that the post-compliance pollutant loadings under the preferred options will reduce total nitrogen loadings to nutrient- impaired waters by 16 percent (428,000 pounds) under Options 3a and 3b, 48 percent (1,270,000 pounds) under Option 3, and 68 percent ( 1,800,000 pounds) under Option 4a.6-37 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-12. L oading Reductions to Impaired Waters by Impairment Type

Impairment Type Number of

Immediate Receiving Waters Impaired b Baseline Loadings

(lbs/yr) Total Pounds per Year to Impaired Waters Removed Under the Regulatory Options
(Percent Reduction) a
Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Arsenic 3 184 0
(0%) 0
(0%) 26.1
(14%) 26.1
(14%) 26.1
(14%) 26.1
(14%) 153
(83%) 153
(83%)

Cadmium 5 317 0
(0%) 2.40
(<1%) 0
(0%) 0
(0%) 2.40
(<1%) 73.1
(23%) 311
(98%) 312
(98%)

Chlorides 3 470,000 0
(0%) 0
(0%) 0
(0%) 0
(0%) 0
(0%) 67 .0
(<1%) 313,000
(67%) 313,000
(67%)

Chromium c 4 120 0
(0%) 0
(0%) 0
(0%) 0
(0%) 0
(0%) 35.0
(29%) 90.0
(75%) 90.0
(75%)
Copper 7 1,950 20.8
(1%) 20.8
(1%) 0
(0%) 0
(0%) 20.8
(1%) 795
(41%) 1,830
(94%) 1,830
(94%)

Lead 7 1,330 0.52
(<1%) 0.52
(<1%) 859
(65%) 859
(65%) 859
(65%) 1,000
(75%) 1,260
(95%) 1,260
(95%)
Manganese 5 559,000 456,000
(82%) 523,000
(94%) 19,7 00
(3.5%) 19,7 00
(3.5%) 543,000
(97%) 546,000
(98%) 547,000
(98%) 559,000
(100%)
Mercury 52 411 67.1
(16%) 69.3
(17%) 129
(31%) 129
(31%) 198
(48%) 293
(71%) 405
(99%) 406
(99%)

Nutrients d 30 2,650,000 0
(0%) 843,000
(32%) 428,000
(16%) 428,000
(16%) 1,270,000
(48%) 1,800,000
(68%) 2,560,000
(97%) 2,350,000
(89%) e
Phosphorus 16 58,400 0
(0%) 2,000
(3%) 16,100
(28%) 16,100
(28%) 18,100
(31%) 34,700
(59%) 56,800
(97%) 57,400
(98%)

Selenium 3 836 0
(0%) 0
(0%) 791
(95%) 791
(95%) 791
(95%) 791
(95%) 836
(100%) 836
(100%)

TDS 4 14,600,000 0
(0%) 0
(0%) 0
(0%) 0
(0%) 0
(0%) 910,000
(6%) 8,280,000
(57%) 8,280,000
(57%)

Zinc 4 10,600 2,530
(24%) 2,550
(24%) 2,840
(27%) 5,390
(51%) 5,390
(51%) 7,900
(74%) 10,600
(100%) 10,600
(100%)

Source: ERG, 2013e; ERG, 2013g.

a – >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction

. b

– For the impaired waters proximity analysis, EPA evaluated 317 immediate receiving water combinations that receive discharges of the evaluated waste

streams.6-38 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options

c – The chromium VI loadings are presented with this impairment category. An impairment type is not designated specifically for c hromium VI.

d – Total nitrogen loadings are presented with this impairment category. An impairment type is not designated specif ically for total nitrogen.

e– Under Regulatory Option 4 FGD wastewater is treated with chemical precipitation plus biological treatment which removes more nitrogen from the wastewater than the evaporation systems; therefore, total nitrogen reductions unde r Regulatory Option 5 are lower than Regulatory Option 4.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-39 6.4.2 Threatened and Endangered Species

As discussed in Section 3.4.3 , EPA identified 224 threatened and endangered species present within surface waters that exceeded NRWQC for the protection of aquatic life under baseline conditions. To assess the potential impro vements to threatened and endangered species under Option 3, EPA evaluated only those species identified as highly vulnerable to changes in water quality (127 of the 224 species) and further excluded species from the analysis based on criteria such as the species is already presumed extinct, species habitat is unlikely to be affected by discharges of the evaluated waste streams (e.g., isolated headwaters), species listing status is due to habitat destruction unrelated to steam electric discharges (e.g., dam ming, stream channelization), and other criteria. Based on the analysis, EPA identified 15 species out of the 127 with a high vulnerability to changes in water quality whose recovery may be enhanced by Option 3. EPA determined that eight of the 15 species identified inhabit waters that will no longer exceed NRWQC for the protection of aquatic life under Option 3 . The species may therefore experience increases in population growth rates as a result of the proposed ELGs. See the Benefits and Cost Analysis for further details on the methodology and results of EPA’s threatened and endangered species analysis. EPA did not estimate potential improvements to threatened and endangered species under Options 3a, 3b, and 4a.

6.4.3 Fish Advisory Waters

States, territories , and authorized tribes issue fish advisories to notify the public (including recreational and subsistence fishers) of water bodies containing fish with elevated and potentially unhealthy contamination levels. EPA identified mercury as the most common pollutant found in combustion wastewater for which fish advisories are issued among the surface waters that receive the evaluated waste streams (see Section 3.4.2 ). EPA determined that 118 of

the 317 immediate receiving water s included in the EA are under a fish advisory for mercury. Under the preferred options , EPA estimates that the number of immediate receiving water s with fish that exceed EPA’s mercury screening value will decrease by 15 percent (under Options 3a and 3b), 20 percent under Option 3, and 43 percent under Option 4a , thereby reducing the potential threat to human health from consuming contaminated fish.

6.4.4 Sensitive Watersheds: Great Lakes and Chesapeake Ba y

As discussed in Section 3.2 , both the Great Lakes and Chesapeake Bay watersheds have a history of pollutant discharges that negatively affect water quality, wild life, and human health.

Both are well -studied, sensitive environments that are affected by pollutants commonly found in combustion wastewater. Discharges of toxic pollutants into these sensitive water bodies by point and nonpoint sources are of concern; however, mercury is one of the primary pollutants of concern in the Great Lakes, 42 

### and nutrients are the primary pollutants of focus in the Chesapeake Bay.

Mercury is a concern in sensitive watersheds such as the Great Lakes due to its bioaccumulation in fish and wildlife and potential impacts on humans. EPA and Environment

42 One of the main environmental pathways for mercury in the Great Lakes is from atmospheric deposition, which is not in the scope of the proposed ELGs.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-40 Canada have documented a range of wildlife impacts from mercury in the Great Lakes

, such a s increased risk of physiological abnormalities in herring gulls [U.S. EPA and Environment Canada, 2009].

EPA identified 26 steam electric power plants that discharge into the Great Lakes

watershed. Table 6-13 presents the pollutant loading reductions into the Great Lakes watershed under the regulatory options considered by EPA. Under the preferred options, EPA estimated that the mercury loadings t o the Great Lakes watershed from steam electric power plants will reduce by 26 percent (under Options 3a and 3b), 30 percent (under Option 3 ), and 34 percent under Option 4a . Selenium discharges will be reduced by 1,400 pounds per year (22 percent

reductio n) under Options 3a and 3b; 4,450 pounds per year (71 percent reduction) under Option 3; and 4,530 pounds per year (73 percent reduction) under Option 4a. Total nitrogen loadings will decrease by over 125,000 pounds under Options 3a and 3b; 500,000 pounds under Option 3; and 635,000 pounds under Option 4a, and total phosphorus loadings decrease by over 5,000 pounds under Options 3a and 3b; 7,000 pounds under Option 3; and 9,000 pounds under Option

4a.

Excessive nutrient loadings to receiving waters signifi cantly affect the ecological stability of freshwater and saltwater aquatic systems. Nutrient enrichment of surface waters can stimulate excessive plant growth that can obstruct sunlight penetration and increase turbidity, which can

result in the death of bottom- dwelling aquatic plants.

EPA identified 20 steam electric power plants that discharge to the Chesapeake Bay

watershed

. Table 6-14 present s the reductions in pollutant loadings to the Chesapeake Bay

watershed as a result of the regulatory options . EPA estimate d that total nitrogen loadings to the Chesapeake Bay watershed from steam electric power plants will reduce by 9 percent (218,000 pounds) under Option 3a, 10 percent (256,000 pounds) under Option 3b, 40 percent ( 988,000 pounds) under Option 3, and 86 percent (2,110,000 pounds) under Option 4a. Total phosphorus loadings will reduce by 17 percent (10,200 pounds) under Option 3a, 18 percent (10,600 pounds) under Option 3b, 22 percent (13,400 pounds) under Option 3, and 84 percent (50,400 pounds) under Option 4a . EPA estimated that arsenic and chromium VI discharges to the Chesapeake Bay watershed from the evaluated waste streams will be reduc ed by over 50 percent under Options 3a, 3b, and 3 and 80 percent under Option 4a. In addition, EPA estimated that manganese and selenium discharges will be reduced by over 80 percent under Option 3 and 90 under Option 4a.6-41 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-13. Total Loadings Removed to the Great Lakes Watershed Under the Regulatory Options

Pollutant Baseline Total Point Source Loadings to

the Great Lakes

Watershed

(lbs/yr) Total Pounds per Year to Great Lakes Watershed Removed Under the Regulatory Options

(Percent Reduction) a

Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Arsenic 4,165 1.98

(<1%) 1.98

(<1%) 1,770

(42%) 1,770

(42%) 1,770

(42%) 1,890

(45%) 4,130

(>99%) 4,140

(>99%)

Boron 1,990,000 0

(0%) 821,000 (41%) 1 80

, 000

(9%) 1 80

, 000

(9%) 1,000,000 (50%) 1,020,000

(51%) 1,290,000 (64%) 1,960,000 (98%)

Cadmium 1,410 91.9

(7%) 99.1

(7%) 266

(19%) 266

(19%) 365

(26%) 416

(30%) 1,390

(99%) 1,390

(99%)

Chromium

VI 380 0

(0%) 10.7

(3%) 223

(59%) 223

(59%) 234

(62%) 241

(64%) 366

(96%) 380

(>99%)

Copper 5,180 16.5

(<1%) 16.5

(<1%) 1,690

(33%) 1,690

(33%) 1,700

(33%) 1,880

(36%) 5,160

(>99%) 5,160

(>99%)

Lead 5,840 3.10

(<1%) 3.10

(<1%) 1,210

(21%) 1,210

(21%) 1,210

(21%) 1.440

(25%) 5,830

(>99%) 5,830

(>99%)

Manganese 166,000 67,300

(41%) 132,000 (80%) 3,440

(2%) 3,440

(2%) 135,000 (82%) 136,000

(82%) 152,000 (92%) 163,000

(98%)

Mercury 117 4.57

(4%) 5.16

(4%) 30.0

(26%) 30.0

(26%) 35.2

(30%) 39.5

(34%) 117

(>99%) 117

(>99%)

Nickel 18,300 739

(4%) 755

(4%) 1,390

(8%) 1,390

(8%) 2,150

(12%) 2,950

(16%) 18,300 (>99%) 18,300 (>99%)

Nitrogen,

total 1,990,000 0

(0%) 44 2 ,000 (2 2 %) 127,000

(6%) 127,000

(6%) 5 68,000 (2 8 %) 637,000

(32%) 1,9 6 0,000 (97%) 1,8 9 0,000 (94%) b

Phosphorus,

total 53,200 0

(0%) 1,600

(3%) 5,460

(10%) 5,460

(10%) 7,060

(13%) 9,330

(18%) 52,500

(99%) 53,000 (>99%)

Selenium 6,240 556

(9%) 3,050

(49%) 1,400

(22%) 1,400

(22%) 4,450

(71%) 4,530

(73%) 6,090

(98%) 6,110

(98%)6-42 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-13. Total Loadings Removed to the Great Lakes Watershed Under the Regulatory Options

Pollutant Baseline Total Point Source Loadings to

the Great Lakes

Watershed

(lbs/yr) Total Pounds per Year to Great Lakes Watershed Removed Under the Regulatory Options

(Percent Reduction) a

Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Thallium 15,900 3.97

(<1%) 41.2

(<1%) 563

(4%) 563

(4%) 604

(4%) 1,360

(9%) 15,900 (>99%) 15,900 (>99%)

Zinc 19,800 1,170

(6%) 1,240

(6%) 6,560

(33%) 6,560

(33%) 7,790

(39%) 8,380

(42%) 19,700 (>99%) 19,600

(>99%) c

Source: ERG, 2013c; ERG, 2013g.

a – >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction.

b – Under Regulatory Option 4

, FGD wastewater is treated with chemical precipitation plus biological treatment which removes more nitrogen from the wastewater than the evaporation systems; therefore, total nitrogen reductions under Reg ulatory Option 5 are lower than Regulatory Option 4.

c – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemica l precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system; therefore, for some immediate receiving water s the metal loadings will increase under Regulatory Option 5 compared to Regulatory Option 4, resulting in the percent reduct ion s of exceedances being lower under Regulatory Option 5. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report (DCN SE01957) for further disc ussion of the regulatory option loadings.6-43 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6

- 14 . Total Loading Reductions to the Chesapeake Bay Watershed Under the Regulatory Options

Pollutant Baseline Total Point Source Loadings to the Chesapeake Bay Watershed (lbs/yr) Total Pounds per Year to Chesapeake Bay Watershed Removed Under the Regulatory Options

(Percent Reduction) a

Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Arsenic 5,180 23.7

(<1%) 23.0

(<1%) 2,630

(51%) 2,650

(51%) 2,660

(51%) 4,560

(88%) 5,100

(99%) 5,140

(>99%)

Boron 3,820,000 394,000

(10%) 1,730,000 (45%) 81,100

(2%) 475,000

(12%) 1,810,000

(47%) 2,050,000

(54%) 2,110,000 (55%) 3,720,000 (97%)

Cadmium 1,820 432

(24%) 444

(24%) 312

(17%) 320

(18%) 756

(41%) 1,590

(88%) 1,780

(98%) 1,790

(98%)

Chromium

VI 681 9.46

(1%) 22.6

(3%) 440

(65%) 450

(66%) 462

(68%) 596

(88%) 653

(96%) 681

(>99%)

Copper 5,150 84.7

(2%) 81.9

(2%) 1,400

(27%) 1,410

(27%) 1,490

(29%) 4,380

(85%) 5,110

(>99%) 5,120

(> 99%)

Lead 5,630 17.5

(<1%) 17.5

(<1%) 1,040

(18%) 1,040

(18%) 1,060

(19%) 4,810

(85%) 5,620

(>99%) 5,620

(>99%)

Manganese 519,000 316,000

(61%) 429,000 (83%) 22,300

(4%) 28,500

(5%) 451,000 (87%) 466,000

(90%) 485,000 (93%) 508,000 (98%)

Mercury 168 21.3

(13%) 22.3

(13%) 47.9

(28%) 48.1

(29%) 70.2

(42%) 142

(85%) 167

(>99%) 168

(>99%)

Nickel 20,700 3,420

(17%) 3,440

(17%) 1,210

(6%) 1,220

(6%) 4,650

(23%) 17,600

(86%) 20,600

(>99%) 20,600

(>99%)

Nitrogen,

total 2,200,000 38,400

(2%) 770 ,000

( 31 %) 218,000

(9%) 256,000

(10%) 988,000 ( 40 %) 2,110,000

(86%) 2,350 ,000

(95%) 2, 147,000 (8 7 %) b

Phosphorus,

total 59,800 363

(<1%) 3,140

(5%) 10,200

(17%) 10,600

(18%) 13,400

(22%) 50,400

(84%) 58,300

(97%) 59,500

(99%)

Selenium 10,100 2,580

(26%) 6,910

(69%) 1,320

(13%) 1,340

(13%) 8,230

(82%) 9,540

(95%) 9,900

(98%) 9,840

(98%) c6-44 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6

- 14 . Total Loading Reductions to the Chesapeake Bay Watershed Under the Regulatory Options

Pollutant Baseline Total Point Source Loadings to the Chesapeake Bay Watershed (lbs/yr) Total Pounds per Year to Chesapeake Bay Watershed Removed Under the Regulatory Options

(Percent Reduction) a

Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Thallium 16,700 24.2

(<1%) 89.0

(<1%) 1,760

(11%) 1,770

(11%) 1,850

(11%) 14,200

(85%) 16,700

(>99%) 16,700

(>99%)

Zinc 21,500 5,380

(25%) 5,510

(26%) 3,590

(17%) 3,600

(17%) 9,090

(42%) 18,700

(87%) 21,400

(>99%) 21,100

(98%) c

Source: ERG, 2013c; ERG, 2013g.

a – >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction.

b – Under Regulatory Option 4 FGD wastewater is treated with chemical precipitation plus biological treatment which removes more nitrogen from the wastewater than the evaporation systems; therefore, total nitrogen reductions under Regulatory Option 5 are lo wer than Regulatory Option 4.

c – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemica l precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, lea chate is only treated with a chemical precipitation system; therefore, for some immediate receiving water s the metal loadings will increase under Regulatory Option 5 compared to Regulatory Option 4, resulting in the percent reduct ions of exceedances being lower under Regulatory Option 5. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report (DCN SE01957) for further discussion of the regulator y option loadings.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-45 6.5 E NVIRONMENTAL AND 

### H UMAN 

### H EALTH 

### I MPROVEMENTS IN 

### D OWNSTREAM 

### S URFACE


### W ATER



### EPA estimates that the environmental and human health improvements within the immediate receiving waters associated with the regulatory options described above will translate into considerable improvements in water quality further downstream from steam ele ctric discharges. EPA calculated downstream receiving water concentrations using EPA’s RiskScreening Environmental Indicators (RSEI) model 43 

### and used the wildlife and human health

models described in Section 4.1.2 to calculate metal concentrations in exposed fish populations and human exposure doses from fish consumption in surface waters downstream from steam electric discharges for five of the regulatory options (Options 1, 2, 3, 4, and 5). EPA then applied adjustment factors to this modeled output to estimate downstream metal concentrations for Options 3a, 3b, and 4a. EPA compared downstream receiving water concentrations, fish tissue concentrations, and human exposure doses to water quality, wildlife, and non- cancer and cancer benchmarks to assess the number of improved river miles associated with the regulatory options.

Table 6-15 presents the number of downstream river miles exceeding a given water quality, wildlife, and human health benchmark for the five regulatory options evaluated in the EA.

Based on the results of the downstream modeling, EPA determined that downstream river miles are impacted by steam electric power plant discharges. Pollutant concentrations continued

to exceed the NRWQC for human health (water and organism) at 11,200 miles downstream from the discharge. EPA estimated that , under the preferred options, up to 3,640 river miles (under Option 3a), 3,860 river miles (under Option 3b), 4,830 river miles (under Option 3), and 6,630 river miles (under Option 4a) downstream from steam electric discharges will no longer exceed the human health NRWQC. The preferre d options will reduce the number of downstream river mile exceedances for each of the NRWQCs and MCLs. This will improve the water quality and aquatic habitats available to wildlife and human populations located outside of the immediate vicinity of steam e lectric power plants. In addition, EPA determined that pollutant loading reductions under the preferred options will also reduce impacts to wildlife that rely on

downstream aquatic habitats as a food source. EPA calculates that up to 4,200 river miles (und er Option 3a), 4,400 river miles (under Option 3b), 5,360 river miles (under Option 3), and 8,180 river miles (under Option 4a) downstream from steam electric discharges will no longer contain fish populations that exceed a NEHC benchmark for minks or eagles. The preferred options will also decrease human exposures via fish consumption to pollutants with the potential to cause

non- cancer health effects in up to 4,100 river miles (under Option 3a), 4,300 river miles (under Option 3b), 5,400 downstream river miles ( under Option 3), and 8,090 river miles (under Option 4a). These results demonstrate that steam electric discharges are impacting surface waters beyond the initial receiving waters and pollutant loading reductions associated with the preferred options will result in substantial environmental and human health improvements for communities beyond the area immediately surrounding steam electric power plants.

43 EPA used pollutant loading discharged to each receiving reach by steam electric plant and metal to estimate

concentrations in downstream reaches. The RSEI model uses a simple dilution and first

- order decay equation to calculate receiving water concentrations (metals are treated as conservative substances). The RSEI model assumes that the plant’s annual discharge is released at a constant rate throughout the year. In addition, EPA included pollutant loadings from the Toxic Inventory Release (TRI) database for other industries to represent background metal concentrations in the downstream receiving waters. For further details on the on the RSEI model methodology

and assumptions, see the Benefits and Cost Analysis.6-46 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-15 . Key Environmental Improvements for Downstream Waters Under the Regula tory Options

Evaluation Criteria Number of River Miles Exceeding Criteria Under

Baseline Conditions Number of River Miles Exceeding Criteria (Percent Reduction from Baseline Conditions) Under the Regulatory Options a

Number of

Miles Percentage

of Total

Downstream

Waters

Evaluated b Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5
Water Quality Results
Freshwater Acute NRWQC 402 1% 228
(43%) 200
(50%) 212
(47%) 203
(50%) 160
(60%) 114
(72 %) 25.7
(94%) 25.7
(94%)

Freshwater Chronic
NRWQC 1,140 3% 953
(16%) 797
(30%) 793
(30%) 774
(32%) 692
(39%) 495
(57 %) 152
(87%) 161
(86%)

Human Health Water and Organism NRWQC 11,200 31% 11,100
(<1%) 11,100
(<1%) 7,560
(33%) 7,340
(34%) 6,370
(43%) 4,570
(59 %) 854
(92%) 708
(94%)
Human Health Organism

only NRWQC 4,310 12% 4,290
(<1%) 4,280
(<1%) 3,050
(29%) 2,970
(31%) 2,610
(39%) 1,880
(56 %) 280
(93%) 215
(95%)
Drinking Water

MCL 965 3% 953
(1%) 924
(4%) 864
(11%) 858
(11%) 836
(13%) 598
(38 %) 37.8
(96%) 31.5
(97%)

Wildlife Results
Fish Ingestion NEHC for

Minks 9,710 27% 7,180
(26%) 7,100
(27%) 5,600
(42%) 5,380
(45%) 4,400
(55%) 3,150
(68 %) 475
(95%) 394
(96%)
Fish Ingestion NEHC for Eagles 15,300 42% 12,100
(21%) 11,900
(22%) 11,100
(27%) 10,900
(29%) 9,940
(35%) 7,120
(53 %) 1,200
(92%) 988
(94%)

Human Health Results

— Non

- Cancer

Non

- cancer reference dose for child (recreational) 13,700 38% 10,900
(20%) 10,800
(21%) 9,780
(29%) 9,560
(30%) 8,520
(38%) 6,080
(56 %) 1,110
(92%) 934
(93%)

Non

- cancer reference dose for adult (recreational) 14,800 41% 11,500
(22%) 11,300
(24%) 10,700
(28%) 10,500
(29%) 9,400
(36%) 6,710
(55 %) 1,170
(92%) 980
(93%)

Non

- cancer reference dose for child (subsistence) 23,600 65% 21,400
(9%) 21,000
(11%) 20,300
(14%) 20,100
(15%) 19,200
(19%) 13,700
(42 %) 5,540
(77%) 5,050
(79%)

Non

- cancer reference dose for adult (subsistence) 22,400 62% 20,000
(11%) 19,500
(13%) 18,600
(17%) 18,400
(18%) 17,400
(22%) 12,400
(45 %) 4,640
(79%) 4,400
(80%)6-47 Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### Table 6-15 . Key Environmental Improvements for Downstream Waters Under the Regula tory Options

Evaluation Criteria Number of River Miles Exceeding Criteria Under

Baseline Conditions Number of River Miles Exceeding Criteria (Percent Reduction from Baseline Conditions) Under the Regulatory Options a

Number of

Miles Percentage

of Total

Downstream

Waters

Evaluated b Option

1 Option

2 Option

3a Option

3b Option

3 Option

4a Option

4 Option

5

Human Health Results

— Cancer

Arsenic cancer risk for child (recreational) 6.25 <1% 6.25
(0%) 6.25
(0%) 2.00
(65%) 2.00
(68%) 1.36
(78%) 0.99
(84%) 1.36
(78%) 1.36
(78%)

Arsenic cancer risk for adult (recreational) 101 <1% 101
(0%) 101
(0%) 53
(48%) 51
(50%) 43.2
(57%) 31
(69%) 5.57
(94%) 5.57
(94%)

Arsenic cancer risk for child (subsistence) 68.5 <1% 68.5
(0%) 68.5
(0%) 36
(47%) 35
(49%) 29.9
(56%) 22
(68%) 1.36
(98%) 1.36
(98%)

Arsenic cancer risk for adult (subsistence) 266 <1% 197
(26%) 199
(25%) 155
(42%) 150
(44%) 133
(50%) 97
( 64 %) 18.2
(93%) 13.3
(95%)

Source: ERG, 2013k; ERG, 2013l.

a – >0 to 20 percent reduction; 21 to 40 percent reduction; 41

- 60 percent reduction ; >60 percent reduction

. b – EPA evaluated a total of 36,200 river miles in the downstream receiving water analysis for metals. Downstream receiving water concentrations are calculated

until one of three conditions occurs: (1) the discharge has traveled 300 km downstream; (2) the disc harge has been traveling downstream for a week; or (3) the

concentration reaches 1 x 10

- 9 mg/L.Section 6

—

Environmental Improvements Under the Proposed Regulatory Options



### 6-48 6.6 A TTRACTIVE 

### N UISANCES



### EPA projects that the pollutant loading reductions associated with the proposed Steam

El ectric ELGs will also decrease the environmental impact to wildlife exposed to pollutants through direct contact with surface impoundments and constructed wetlands at steam electric power plants. Documented case studies demonstrate that wildlife living nea r steam electric

surface impoundments exhibit elevated levels of arsenic, cadmium, chromium, lead, mercury, selenium, strontium, and vanadium [Burger et al., 2002; Bryan et al., 2003, Hopkins et al., 1997, 1998, 2000, 2002, 2006; Nagle et al., 2001, Rattner et al., 2006]. Multiple studies have linked attractive nuisance areas at steam electric power plants to diminished reproductive success [Hopkins et al., 2002, 2006; Nagle et al., 2001]. EPA estimates that the pollutant loadings associated with the prefer red options will decrease the exposure of wildlife populations to toxic pollutants and reduce the threat combustion residuals surface impoundments pose to surrounding

wildlife.

6.7 O THER 

### S ECONDARY 

### I MPROVEMENTS



### In addition to the improvements discussed above, other secondary, or ancillary, improvements will occur to other resources that are associated directly or indirectly as a result of the preferred options. These would include aesthetic and recreational improvements, reduced economic impacts such as clean u p and treatment costs in response to contamination or impoundment failures, reduced injury associated with pond failures, reduced water usage, reduced potential for algal blooms and reduced air emissions. EPA did not quantify these improvements as part of the EA due to a lack of data from which to do so.Section 7

— Conclusions



### 7-1 

# SECTION 7 CONCLUSIONS

Based on evidence in the literature, documented cases studies, and mode led receiving water pollutant concentrations, it is clear that current combustion wastewater discharge practices at steam electric power plants are impacting the surrounding ecological environments and pose a potential human health threat to nearby communi ties. The U.S. Environmental Protection Agency (EPA) estimated that discharges from s team electric power plants contribute at least 50 to 60 percent of the toxic-weighted pollutant loadings of the combined discharges of all

industrial categories currently required to report discharges to U.S. waters. These discharges add large quantities of toxic bioaccumulative metals (e.g., selenium, arsenic, and mercury) to the aquatic environment. Substantial evidence exists that metals from combustion wastewater

discha rges are transferring from the aquatic environment to terrestrial food webs; this indicates the potential for broader impacts to ecological systems by altering population diversity and community dynamics in the areas surrounding steam electric power plants . Ecosystem recovery from exposure to combustion wastewater discharges can be extremely slow and even short periods of exposure (e.g., less than a year) can cause observable ecological impacts that last for years. The strong bioaccumulative properties and long residence times of pollutants in combustion wastewater reinforce the threat of these wastes to the local environment, and many of the impacts may not be fully realized for years to come.

In addition, EPA’s modeling demonstrated pollutant loadings from combustion wastewater discharges are impacting areas beyond the immediate receiving waters and pose a threat to wildlife and human populations in thousands of river miles downstream from steam electric power plants under current discharge practices. Furthermore, EPA predicts that the recently promulgated Clean Air Act requirements (i.e., Mercury and Air Toxics Standards and

Cross

- State Air Pollution Rule ) and other state and local regulations may lead to additional air pollution controls (and resulting was te streams) that will increase the pollutant loadings to surface waters in the future. EPA determined that these additional pollutant loadings above current baseline conditions will increase the number of immediate receiving waters exceeding water quality, wildlife, and human health benchmarks in the future. 44

44 As part of EPA’s profile of the steam electric industry, EPA established a baseline of January 1, 2014. Therefore, to evaluate the impacts of the proposed rule on the industry, EPA used available data to account for changes to the industry that are expected to occur by January 1, 2014 (e.g., plant/unit retirements, flue gas desulfurization [FGD] system installations). However, EPA recognizes that some recently promulgated Clean Air Act requirements and

ot her state and local regulations may lead to additional air pollution controls (and resulting waste streams) at existing plants beyond this date. In an effort to confirm that the proposed requirements would be economically achievable in such cases, EPA con ducted a sensitivity analysis that forecasts future installations of air controls (i.e., wet FGD systems) through 2020 44 and the associated costs of complying with the proposed regulatory requirements for the wastewater that may result from the forecasted a ir control installations. Based on this sensitivity analysis, EPA determined that there are additional costs and pollutant loadings associated with these future installations to comply with the proposed effluent limitations guidelines and standards (ELGs). Additionally, EPA determined that the increase in loadings would result in an increase in environmental exceedances for the baseline conditions. While there are some increases in exceedances, some of these new exceedances will also go away under the regul atory option scenarios based on the treatment of the FGD wastewater, which also results in increased benefits associated with the proposed rule. The details of the sensitivity analysis are described in the ERG memorandum Flue Gas Desulfurization Future Pr ofile Sensitivity Analysis (DCN SE01989).Section 7

— Conclusions



### 7-2 Steam electric power plants discharge c ombustion wastewater into water bodies used for

recreation , and these discharges can present a potential threat to human health. Documented fish

kills have resu lted in states issuing fish advisories to protect the public from exposure to fish with elevated pollutant concentrations in recreational waters that receive combustion wastewater. Leachate from combustion residuals surface impoundment s and landfills are k nown to impact

off -site ground water and drinking water wells at concentrations above maximum contaminant level (MCL) drinking water standards and pose a potential threat to human health.

EPA determined that the preferred options will result in quantifiabl e improvements in ecological and human health by reducing immediate receiving water metal concentrations 45 

### by approximately 22 to 36 percent (under Options 3a and 3b), 25 to 48 percent (under Option 3 ), and 47 to 60 percent (under Option 4a) . The preferred options result in the following environmental improvements:

• 

### 29 percent reduction (Options 3a and 3b), 35 percent reduction (Option 3), or 55 percent reduction (Option 4a) in the number of immediate receiving waters exceeding a National Recommended Water Qu ality Criteria (NRWQC) for the protection of aquatic life;

• 

### 14 percent reduction (Option 3a), 15 percent reduction (Option 3b), 18 percent reduction (Option 3), or 41 percent reduction (Option 4a) in the number of immediate receiving waters exceeding a NRWQ C for the protection of human health;

• 

### 23 percent reduction (Option 3a), 24 percent reduction (Option 3b), 30 percent reduction (Option 3), or 51 percent reduction (Option 4a) in the number of immediate receiving waters that support fish that pose a threat to piscivorous wildlif e;

• 

### 40 percent reduction (Option 3a), 60 percent reduction (Options 3b and 3), or 80 percent reduction (Option 4a) in the number of immediate receiving waters that support fish that pose a cancer risk to exposed populations; and

• 

### 19 percent reduction (Option 3a), 21 percent reduction (Option 3b), 26 percent reduction (Option 3), or 47 percent reduction (Option 4a) in the number of immediate receiving waters that support fish that pose a potential threat to cause non- cancer health e ffects in exposed populations.

The analyses presented in the environmental assessment (EA) focus on quantifying the environmental improvements within rivers and lakes from post-compliance pollutant loading

reductions for metals and nutrients. While extens ive, the environmental improvements quantified above do not encompass the full range of environmental improvements that will result from the proposed Steam Electric ELGs. EPA estimated that post-compliance pollutant loading reductions will improve wildlife and environmental health by reducing the:

• 

### Loadings of bioaccumulative metals to the broader ecosystem, reducing long- term exposures and sublethal ecological effects;

• 

### Sublethal chronic effects on aquatic life not captured by the NRWQC;

45 Reductions apply to the subset of metals evaluated in the environmental assessment (i.e., arsenic, cadmium, chromium VI, copper, lead, mercury, nickel, selenium, thallium, and zinc).Section 7

— Conclusions



### 7-3 • 

### Impacts to aquatic a nd aquatic-dependent wildlife population diversity and community structures; and

• 

### Exposure of wildlife to pollutants through direct contact with surface impoundment s and constructed wetlands at steam electric power plants.

Data limitations prevented EPA fro m appropriately modeling the scale and complexity of the ecosystem processes potentially impacted by combustion wastewater and therefore not fully quantifying the improvements listed above. However, documented case studies in the literature

reinforce that these impacts are common in the environments surrounding steam electric power plants and fully support the conclusion that reducing pollutant loadings will improve overall

environmental and wildlife health.

Although the EA quantifies impacts to wildlife that consume fish contaminated with metals from combustion wastewater, it does not capture the full range of exposure pathways through which bioaccumulative metals can enter the surrounding food web. Wildlife can encounter bioaccumulative metals from combustion wastewater discharges through direct exposure, drinking water, consumption of contaminated vegetation, and consumption of contaminated prey other than fish. Therefore, the quantified improvements underestimate the complete loadings of bioaccumulative metals that can impact wildlife in the ecosystem. EPA

estimates that the post-compliance pollutant loading reductions associated with the preferred options will lower the total amount of bioaccumulative metals entering the food web near steam electric power plants.

EPA estimates that reducing pollutant loadings will also lower the occurrence of

sub lethal effects associated with many of the pollutants in steam electric wastewater that may not be captured by comparisons with NRWQC for aquatic life. Well -documented studies suggest that organisms in aquatic environments near steam electric power plants exhibit chronic effects such as changes in metabolic rates, decreased growth rates, changes in morphology (e.g., fin erosion, oral deformities), and changes in behavior (e.g., decreased ability to swim, catch prey, or escape from predators) that can negatively affect long -term survival [Raimondo et al., 1998; Rowe et al., 1996, 2002]. However, these effects are not fully quantified in the EA due to data limitations, and therefore improvements to wildlife health and survival from the proposed ELGs may be underestimated. Reduced organism survival rates from chronic effects such as abnormalities can alter interspecies relationships (e.g., declines in the abundance or quality of prey) and prolong ecosystem recovery. EPA was unable to quantify changes to aquatic and wildlife population diversity and community dynamics; however, population effects (i.e., decline in number and type of organisms present) attributed to exposure to combustion wastewater are well documented in the literature [Lemly, 1985a; Garrett and I nman, 1984; As surface impoundments accumulate fly ash, bottom ash and flue gas desulfurization sludges, they can begin to fill up and lose their treatment capability.Section 7

— Conclusions



### 7-4 Sorensen et al., 1982]. Changes in aquatic populations can alter the structure of aquatic communities and cause cascading effects within the food web that result in long- term impacts to ecosystem dynamics. EPA estimates that post- compliance pol lutant loading reductions associated with the proposed ELGs will lower the stressors that can alter population and community dynamics and will improve the overall function of ecosystems surrounding steam electric power plants.Section 8

— References



### 8-1 

# SECTION 8 REFERENCES

AECOM. 2009. Executive Summary: Root Cause Analysis of TVA Kingston Dredge Pond Failure on December 22, 2008. Kingston Fossil Plant, Harriman, Tennessee. (June).

Available online at: http://www.tva.gov/kingston/rca/

. 

### DCN SE01944.

Andersen L.J. and B. Madsen, 1983. Water Science Technology, 15: 207-212 (As cited in Prasad et al., 1996).

ASU. 2009. Appalachian State University. Preliminary Summary Report from Water, Sediment and Fish samples collected at the TVA Ash Spill by Appalachian State University, Appalachian Voices, Tennessee Aquarium and Wake Forest University

. DCN SE01945.

ATSDR. 1998a. Agency for Toxic Substances and Disease Registry. Health Consultations: Martin Creek Lake. Department of Health and Human Services. Atlanta, GA (September).

DCN SE01877.

ATSDR. 1998b. Health Consultations: Brandy Branch Reservoir. Department of Health and

Human Services. Atlanta, GA (September). DCN SE01878.

ATSDR. 1998c. Health Consultations: Welsh Reservoir. Department of Health and Human

Services. Atlanta, GA (September). DCN SE01880.

ATSDR. 1999. Mercury Fact Sheet. Department of Health and Human Services. Atlanta, GA.

Available online at: http://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=113&tid=24 . DCN SE1990.

ATSDR. 2008a . Cadmium Fact Sheet. Department of Health and Human Services. Atlanta, GA (September). DCN SE01898.

ATSDR. 2008b. Toxicological Profile for Manganese. Department of Health and Human Services. Atlanta, GA (September) . DCN SE01899.

ATSDR. 2010a. Minimal Risk Levels (MRLs) . Department of Health and Human Services. Atlanta, GA (December)

. Available online at: http://www.atsdr.cdc.gov/mrls/pdfs/atsdr_mrls_december_2010.pdf

. DCN SE01901.

ATSDR. 2010b. Toxicological Profile for Boron . Department of Health and Human Services. Atlanta, GA (November). DCN SE01902.

Baba, A. and A. Kaya. 2004. Leaching Characteristics of Solid Wastes from Thermal Power Plants of Western Turkey and Comparison of Toxicity Methodologies. Journal of Environmental Management, 73: 199–207. DCN SE01866.

Ballard, A.M. 2012. “Water Pollution Groundwater Violations Found Near All 14 North

Carolina Power Plants With Ash Ponds.” BNA Today . (January 26). DCN SE01896.

Barrows, M.E., S.R. Petrocelli, K.J. Macek, and J.J. Carroll. 1980. Chapter 24: Bioconcentration

and E limina tion of S elected W ater P ollutants by B luegill Sunfish (Lepomis macrochirus). Dynamics, Exposure and Hazard Assessment of Toxic Chemicals . Edited by R. Haque. Ann Arbor, MI: Ann Arbor Science. DCN SE01897.

Baumann, P.C. and R.B. Gillespie, 1986. Selenium Bioaccumulation in Gonads of Largemouth Bass and Bluegill from Three Power Plant Cooling Reservoirs. Environmental Toxicology and Chemistry, 5: 695–701. DCN SE01846.Section 8

— References



### 8-2 Benson, W.H., and W.J. Birge. 1985. Heavy Metal Tolerance in Metallothionein Induction in

Fa thead Minnows: Results from Field and Laboratory Investigations. Environmental Toxicology and Chemistry, 4(2): 209–217. DCN SE01849.

Besser, J. M., J.P. Giesy, R.W. Brown, J.M. Buell, and G.A. Dawson, 1996. Selenium Bioaccumulation and Hazards in a Fish Community Affected by Coal Fly Ash Effluent. Ecotoxicology and Environmental Safety, 35: 7–15. DCN SE02139.

Birge, W.J. 1978. Aquatic Toxicology of Trace Elements of Coal and Fly Ash. Energy and Environmental Stress in Aquatic Systems, Selected Papers from a Symposium, held at Augusta, Georgia November 2 –4, 1977. DCN SE01854.

Bryan, A.L., Jr, W.A. Hopkins, J.A. Baionno, and B.P. Jackson. 2003. Maternal Transfer of Contaminants to Eggs in Common Grackles (Quiscalus quiscala) Nesting on Coal Fly Ash

Basins. Arc hives of Environmental Contamination and Toxicology, 45(2): 273–277. DCN

SE01836.

Burger, J., K.F. Gaines, C.G. Lord, I.L. Brisbin, S. Shukla, and M. Gochfield. 2002. Metal Levels in Raccoon Tissues: Differences On and Off the Department of Energy's Savannah River Site in South Carolina. Environmental Monitoring and Assessment, 74: 67–84. DCN

SE01869.

Cantor, K.P., C.M. Villanueva, C.T. Silverman, J.D. Figueroa, F. X. Real, M. Garcia -Closas, N. Malats, S. Chanock, M. Yeager, A. Tardon, R. Garcia-Closas, C. Serra., A. Carrato, G.

Castano -Vinyals, C. Samanic, N. Rothman, and M. Kogevinas. 2010. Polymorphisms in GSTT1, GSTZ1, and CYP2E1, Disinfection By-products, and Risk of Bladder Cancer in Spain. Environmental Health Perspectives, 118(11): 1545–1550. DCN SE1981.

Carlson, C.L. and D.C. Adriano. 1993. Environmental Impacts of Coal Combustion Residues. Journal of Environmental Quality, 22: 227–247. DCN SE02144.

Charl otte Observer, 2010. Coal Ash in Water Worries Officials . (October). DCN SE01879.

Cherkauer D.S. 1980. The Effect of Fly Ash Disposal on a Shallow Ground- water System, Ground Water, 18(6): 544–550. DCN SE01890.

Cherry, D.S., R.J. Currie and D.J. Soucek. 2000. Review of the Global Adverse Environmental Impacts to Ground Water and Aquatic Ecosystem from Coal Combustion Wastes. Hoosier Environmental Council and Citizens Coal Council. Indianapolis, Indiana (March). DCN

SE01884.

Chesapeake Bay Program. 1999. Che sapeake Bay Basin Toxics Loading and Release Inventory

. Annapolis, MD (May). DCN SE01903.

Clark, D.R. 1987. Selenium Accumulation in Mammals Exposed to Contaminated California Irrigation Drainwater. The Science of the Total Environment , 66: 147–168. DCN SE 01874.

Coughlan, D.J. and J.S. Velte. 1989. Dietary Toxicity of Selenium-Contaminated Red Shiners to Striped Bass. Transactions of the American Fisheries Society , 118 : 400–408. DCN SE01850.

Cross, F.L. 1981. Coal P ile Environmental I mpact Problems. Pollution Engineering, 13(7): 35–

37. DCN SE01881.

Crutchfield, J. and S. Ferguson. 2000a. Predicting Recovery of a Fish Population after Heavy Metal Impacts. Environmental Science & Policy, 3: 183 –189. DCN SE 01838.Section 8

— References



### 8-3 Crutchfield, J.U., Jr. 2000b. Recovery of a Power Plant Cooling Reservoir from Selenium Bioaccumulation. Environmental Science & Policy, 3: 145–163. DCN SE02138.

Cumbie, P.M. and S.L. Van Horn. 1978. Selenium Accumulation Associated with Fish Mortality and Reproductive Failure. Proceedings of Annual Conference of the Southeastern Association of Fish and Wildlife, 32 : 612–624. DCN SE01851.

DOE . 1992. Department of Energy

. Ecological Effects of Contaminants in McCoy Branch , 1989- 1990. Washington, DC (January). DCN SE01837.

DRBC. 2006. Delaware River Basin Commission. Assessment of Water Column Data Collected in Response to a Fly Ash Release on the Delaware River. (June). DCN SE 01947.

EPRI . 1997. Electric Power Research Institute

. Coal Combustion By-products and Low-Volume Wastes Comanagement Survey , EPRI TR -108369, Palo Alto, CA (as cited in Rowe et al., 2002).

EIP (Environmental Integrity Project), Earthjustice, and Sierra Club. 2010a. Out of Control: Mounting Damages from Coal Ash Waste Sites. (February). DCN SE 00351.

EIP, Earthjustice, and Sierra Club. 2010b

. In Harm's Way: Lack of Federal Coal Ash Regulations Endangers Americans and their Environment. (August). DCN SE 01365.

EIP. 2011. Risky Business: Coal Ash Threatens America’s Groundwater Resources at 19 More Sites. (December). DCN SE01985.

ERG . 2010. Eastern Research Group, Inc. Drinking Water Treatment Technologies that Can Reduce Metal and Selenium Concentrations Associated with Discharges from Steam Electric Power Plants. Chantilly, VA. DCN SE02154.

ERG. 2013a. Water Quality Model: Plant and Receiving Water Characteristics Memorandum. Chantilly, VA. DCN SE01955.

ERG. 2013b. Literature Search Database . Chantilly, VA. DCN SE01962.

ERG. 2013c. Loadings Analysis for the Steam Electric ELGs Environmental Assessment

Memorandum. Chantilly, VA. DCN S E01956.

ERG. 2013d. Comparison of Steam Electric Industry Toxic Loadings to Other Industrial Dischargers Memorandum. Chantilly, VA. DCN SE02155.

ERG. 2013e. Proximity Analysis Methodology Memorandum. Chantilly, VA. DCN SE02151.

ERG. 2013f. Literature Revie w – Impacts of Coal Pile Runoff and Leachate. Chantilly, VA.

DCN SE02153.

ERG. 2013g. Pollutant Loadings Supporting Documentation Memorandum. Chantilly, VA. DCN

SE03887.

ERG. 2013h. Water Quality Model Supporting Documentation Memorandum. Chantilly, VA.

DC N SE03888.

ERG. 2013i. Wildlife and Human Health Models Supporting Documentation Memorandum. Chantilly, VA. DCN SE03889.

ERG. 2013j. Fish Tissue Comparison Supporting Documentation Memorandum. Chantilly, VA.

DCN SE03890.

ERG. 2013k. Downstream Model Supporting Documentation Memorandum. Chantilly, VA.

DCN SE03891.Section 8

— References



### 8-4 ERG. 2013l. Supporting Documentation for Summarization of Environmental Assessment Analyses Memorandum. Chantilly, VA. DCN SE03892.

ERG. 2013m. Fish Consumption Rate for Cohorts Memorandum. Chantilly, VA. DCN SE01963.

ERG. 2013n. EA Model Validation and Calibration Memorandum. Chantilly, VA. DCN

SE01986.

Evers, D.C., J.G. Wiener, C.T. Driscoll, D.A.,Gay, N. Basu, B.A. Monson, K.F. Lambert, H.A. Morrison, J.T. Morgan, K.A. Williams, and A.G. Soehl. 2011. Great Lakes Mercury Connections: The Extent and Effects of Mercury Pollution in the Great Lakes Region. Biodiversity Research Institute. Gorham, Maine. Report BRI 2011–18. DCN SE01904.

Fleming, L.N., H.N. Abineth, and H.I. Inyang, 1996. Leachate pH Effects on the L eachability of

M etals from C oal F ly Ash. Journal of Soil Contamination, 5(1): 53–59 (as cited in Baba and Kaya, 2004).

Garrett, G.P. and C.R. Inman . 1984. Selenium-Induced C hanges in Fish Populations in a H eated Reservoir. Proc. Ann. Conf. Southeast Assoc. Fish. Wildl. Agencies, 38 : 291–301. DCN

SE01885.

Gazette. 2011. Mirant Facing Lawsuit in Federal Court Over Coal Waste . (January). DCN

SE01954.

Gillespie, R.B. and P.C. Baumann. 1986. Effects of High Tissue Concentrations of Selenium on Rep roduction by Bluegills. Transactions of the American Fisheries Society , 115 : 208–213.

DCN SE01852.

Guthrie, R.K. and Cherry, D.S. 1976. Pollutant Removal from Coal Ash Basin Effluent. Journal of the American Water Resources Association, 12(5): 889–902. DCN SE01853.

Hofer, C., F.J. Gallagher, and C. Holzapfel. 2010. Metal Accumulation and Performance of Nestlings of Passerine Bird Species at an Urban Brownfield Site. Environmental Pollution,

158 : 1207–1213. DCN SE01867.

Hopkins, W.A., M.T. Mendonça, and J.D. Congdon. 1997. Increased circulating levels of testosterone and corticosterone in southern toads, Bufo terrestris, exposed to coal combustion

waste. Gen Comp Endocrinol, 108: 237–246. DCN SE02146.

Hopkins, W.A., M.T. Mendonça, C.L. Rowe, and J.D. Congdon. 1998. Elevated Trace Element Concentrations in Southern Toads, Bufo terrestris, Exposed to Coal Combustion Waste. Archives of Environmental Contamination and Toxicology, 35 : 325–329. DCN SE02140.

Hopkins, W.A., J.W. Snodgrass, J.H. Roe, B.P. Jackson, J.C. Gariboldi, and J.D. Congdon. 2000. Detrimental Effects Associated with Trace Element Uptake in Lake Chubsuckers Erimyzon Sucetta Exposed to Polluted Sediments. Arch. Environ. Contam. Toxicol , 39 : 193–199. DCN

SE01841.

Hopkins, W.A., J.W. Snodgrass, J.H. Roe, B.P. Staub, B.P. Jackson, and J.D. Congdon. 2001. Effects of Food Ration on Survival and Sublethal Responses of Lake Chubsuckers (Erimyzon sucetta) Exposed to Coal Combustion Wastes. Aquatic Toxicology, 21(5): 906–913. DCN

SE02141.

Hopkins, W.A., J.H. Roe, J.W. Snodgrass, B.P. Staub, B.P. Jackson, and J.D. Congdon. 2002. Effects of Chronic Dietary Exposure to Trace Elements on Banded Water Snakes Nerodia fasciata). Environmental Toxicology and Chemistry, 21(5) : 906–13. DCN SE01855.Section 8

— References



### 8-5 Hopkins, W.A., J.W. Snodgrass, B.P. Staub, B.P. Jackson, and J.D. Congdon. 2003. Altered Swimming Performance of Benthic Fish (Erimyzon sucetta) Exposed to Contaminated

Sediments ” Arch Environmental Contam. Toxicol., 44 : 383–389. DCN SE01856.

Hopkins, W.A., S.E. Durant, B.P. Staub, C.L. Rowe, and B.P. Jackson. 2006. Reproduction, Embryonic Development, and Maternal Transfer of Contaminants in the Amphibian Gastrophryne carolinensis. Environmental Health Perspectives , 114(5) : 661–666. DCN

SE01839.

King, K.A., T.W. Custer, and D.A. Weaver . 1994. Reproductive Success of Barn Swallows Nesting Near a Selenium

- Contaminated Lake in East Texas, U .S. Environmental Pollution

, 84 : 53–58. DCN SE01870.

Kopsick, D.A. and E.E. Angino. 1981. Effect of L eachate Solutions from F ly and B ottom Ash on Groundwater Quality. Journal of Hydrology, 54 : 341–356. DCN SE01865.

Kumada, H., S. Kimura, M. Yokote, and Y. Matida. 1972. Acute and Chronic Toxicity, U ptake, and Retention of Cadmium in Freshwater Organisms. Bulletin of Freshwater Fisheries

Researc h Laboratory , 22(2): 157–165. DCN SE01894.

Lemly, A.D. 1985a. Toxicology of Selenium in a Freshwater Reservoir: Implications for Environmental Hazard Evaluation and Safety. Ecotoxicology and Environmental Safety, 10:

314–338. DCN SE01842.

Lemly, A.D. 1985b . Ecological Basis for Regulating Aquatic Emissions from the Power Industry: The Case with Selenium. Reg. Toxicol. Pharmacol., 5: 465–486. DCN SE01887.

Lemly, A.D., 1997. Ecosystem Recovery Following Seleniu m Contamination in a Freshwater Reservoir. Ecotoxicology and Environmental Safety, 36: 275–281. DCN SE02138.

Lemly, A. D. 1999. Selenium Transport and B ioaccumulation in A quatic E ecosystems: a Proposal for W ater Q uality C riteria Based on H ydrological U nits . Ecotoxicology and Environmental Safety. 42 , 150–156 (as cited in Rowe et al., 2002).

Liang, L. and P. Singer. 2003. Factors Influencing the Formation and Relative Distribution of Haloacetic Acids and Trihalomethanes in Drinking Water. Environ. Sci. Technol, 37: 2920–

2928. DCN SE01982.

Maryland Associated of County (MACo). 2007. Impacts of Fly Ash on Groundwater in Anne Arundel County, Maryland. Health Officers Meeting. (October). DCN SE01946.

Metcalf and Eddy, Inc. 2003. Wastewater Engineering: Treatment and Reuse . McGraw

- Hill, Inc.

4th edition. DCN SE01967.

MDNR. 2007. Maryland Department of Natural Resources. Assessment of Water Quality Impacts Associated with Use of Coal Combustion Products as Structural Fill at the BBSS

Site. Annapolis, Maryland. DNR 12-6182007-221. (June). DCN SE02147.

MDNRE. 2010. Michigan Department of Natural Resources and Environment. Hazardous Waste Management System, Identification and Listing of Special Wastes. Disposal of Coal

Combustion Residuals from Electric Utilities Docket Comments. EPA

- HQ

- RCRA -2009-

0640-6815 . DCN SE0 1895.

Murphy, B.R., G.J. Atchison, and A.W. McIntosh. 1978. Cadmium and Z inc in M uscle of

B luegill ( Lepomis macrochrius ) and Largemouth B ass ( Micropterus solmoides ) from an Industrially Contaminated L ake. Environmental Pollution

, 17(4) : 253−257 (As cited in U.S. EPA, 2010b).Section 8

— References



### 8-6 Nagle, R.D., C.L. Rowe, and J.D. Congdon. 2001. Accumulation of Selective Maternal Transfer of Contaminants in the Turtle Trachemys scripta Associated with Coal Ash Disposition. Archives of Environmental Contamination and Toxicology, 40 : 531–536. DCN SE01843.

NOAA 2008. National Ocea nic and Atmospheric Association. Screening Quick Reference Tables (SQuiRTs ) . DCN SE01905.

NPS. 1997. National Parks Service. Environmental Contaminants Encyclopedia Selenium Entry. Fort Collins, Colorado. (July). DCN SE01906.

NRC. 2006. National Research Council of the National Academies. Managing Coal Combustion

Residues in Mines. National Academies Press , Washington, DC. DCN SE02136.

Ohlendorf, H.M., D.J. Hoffman, M.K. Saiki, and T.W. Aldrich . 1986. Embryonic Mortality and Abnormalities of Aquatic Birds: Apparent Impacts of Selenium from Irrigation Drainwater. The Science of the Total Environment, 52 : 49–63. DCN SE01873.

Ohlendorf, H.M., A.W. Kilness, J.L. Simmons, R.K. Stroud, D.J. Hoffman, and J.F. Moo re

. 1988a. Selenium Toxicosis in Wild Aquatic Birds. Journal of Toxicology and Environmental

Health , 24 : 67–92. DCN SE01882.

Ohlendorf, H.M., R.L. Hothem, and T.W. Aldrich . 1988b. Bioaccumulation of Selenium by Snakes and Frogs in the San Joaquin Valley, California. Copeia, 3 : 704–710. DCN SE01883.

Ohlendorf, H.M., R.L. Hothem, and D. Welsh . 1989. Nest Success, Cause- Specific Nest Failure, and Hatchability of Aquatic Birds at Selenium -Contaminated Kesterson Reservoir and a

Reference Site . The Condor, 91 : 787–796. DCN SE01872.

Ohlendorf, H.M., R.L. Hothem, C.M. Bunck, and K.C. Marois, 1990. Bioaccumulation of Selenium in Birds at Kesterson Reservoir, California. Archives of En vironmental Contamination and Toxicology, 19 : 495–507. DCN SE01871.

Prasad B, N.N. Banjeree, and B.B. Dhar. 1996. Environmental Assessment of Coal Ash Disposal: A Review. Journal of Scientific & Industrial Research , 55 : 772–780. DCN

SE01891.

Pruitt , L., 2000. Indiana's First HCP Conserves Least Tern - Brief Article. Endangered Species

Bulletin

. Accessed online at: FindArticles.com. DCN SE02148.

Raimondo, S.M., C.L. Rowe, and J.D. Congdon. 1998. Exposure to Coal Ash Impacts Swimming Performance and Predator Avoidance in Larval Bullfrogs. Journal of Herpetology, 32(2): 289–292. DCN SE01857.

Rattner, B.A., M.A McKernan, K.M. Esereich, W.A. Link, G.H Olsen, D.J. Hoffman, K.A. Knowles, and P.C. McGowan. 2006. Toxicity and Hazard of Vanadium to Mallard Ducks (Anas platyrhynchos) and Canada Geese (Branta canadensis). Journal of Toxicology and

Environmental Health , Part A, 69: 331–351. DCN SE01835.

Robertson, D.M. and D.A. Saad. 2011. Nutrient Inputs to the Laurentian Great Lakes By Source and Watershed Estimated Using SPARROW Watershed Models. Journal of the American

Water Resources Association , 47(5): 1011–1033. DCN SE01928.

Roe, J.H., W.A. Hopkins, and B.P. Jackson. 2005. Species- and Stage- Specific Patterns of Trace Element Accumulation (tissue concentration) in Amphibians Exposed to Coal-Combustion

Wastes. Environmental Pollution, 136 : 353–363. DCN SE01847.Section 8

— References



### 8-7Roe, J.H., W.A. Hopkins, S.E. Durant, and J.M. Unrine. 2006. Effects of Competition and CoalCombustion Wastes on Recruitment and Life History Characteristics of Salamanders in Temporary Wetlands. Aquatic Toxicology, 79(2): 176–84. DCN SE01863.

Rowe, C.L., O.M. Kinney, J.D. Congdon. 1996. Oral Deformities in Tadp oles (Rana catesbeiana) Associated with Coal Ash Deposition: Effects on Grazing Ability and Growth. Freshwater Biology: 36, 723 –730. DCN SE02142.

Rowe, C.L., O.M. Kinney, R.D. Nagle, and J.D. Congdon. 1998a. Elevated Maintenance Costs in an Anuran Exposed to a Mixture of Trace Elements during the Embryonic and Early Larval Periods. Physiological Zoology, 71(1): 27–35. DCN SE01845.

Rowe, C.L., O.M. Kinney, and J.D. Congdon. 1998b. Oral Deformities in Tadpoles of the Bullfrog (Rana catesbeiana) Caused by Cond itions in a Polluted Habitat. Copeia, 1: 244–246.

DCN SE01858.

Rowe, C.L., W.A. Hopkins, and V.R. Coffman. 2001. Failed Recruitment of Southern Toads (Bufo terrestris) in a Trace Element -Contaminated Breeding Habitat. Archives of

Environmental Contaminatio n and Toxicology, 40(3): 399–405. DCN SE01859.

Rowe, C.L., W.A. Hopkins, and J.D. Congdon. 2002. Ecotoxicological Implications of Aquatic Disposal of Coal Combustion Residues. Environmental Monitoring & Assessment, 80(3):

207–276. DCN SE02143.

Ruhl, L., A. Vengosh, G.S. Dwyer, H. Hsu-Kim, G. Schwartz, A. Romanski, and S.D. Smith. 2012. The Impact of Coal Combustion Residue Effluent on Water Resources: A North Carolina Example. Environmental Science and Technology, 46: 12226–12233. DCN

SE01984.

Sager, D.R. and C.R. Colfield. 1984. Differential Accumulation of Selenium among Axial Muscle, Reproductive and Liver Tissues of Four Warmwater Fish Species. Journal of the American Water Resources Association, 20(3): 359–363. DCN SE01860.

Schultz, S. 2008. Constellation Reaches $54M Settlement on Fly Ash Lawsuit. Baltimore Business Journal. (December). DCN SE02149.

Simsiman, G.V.

, G. Chesters, and A.W. Andren. 1987. Effect of Ash D isposal Ponds on Groundwater Q uality at a C oal -F ired P ower Plant. Water Resource s, 21(4) : 417–426. DCN

SE01868.

Snodgrass, J.W., W.A. Hopkins, J. Broughton, D. Gwinna, J.A. Baionno, and J. Burge. 2004. Species -Specific Responses of Developing Anurans to Coal Combustion Wastes. Aquatic Toxicology, 66: 171–182. DCN SE01844.

Sorensen, E.M.B., C. W. Harlan, and J.S. Bell . 1982. Renal changes in selenium-exposed fish. Amer. J. Forensic Med. Pathol., 3 : 123–129. DCN SE01888.

Sorensen, E.M.B., J.S. Bell, and C.W. Harlan. 1983. Histopathological Changes in SeleniumExposed Fish. American Journal of Forensic Medicine and Pathology, 4(2) : 111–123. DCN

SE01862.

Sorensen, E.M.B and T.L. Bauer. 1984a. A Correlation Between Selenium Accumulation in Sunfish and Changes in Condition Factor and Organ Weight. Environmental Pollution (Series A), 32: 357–366. DC N SE01886.

Sorensen, E.M.B., P.M. Cumbie, T.L. Bauer, J.S. Bell, and C.W. Harlan. 1984b. Histopathological, Hematological, Condition -Factor, and Organ Weight Changes AssociatedSection 8

— References



### 8-8 with Selenium Accumulation in Fish from Belews Lake, North Carolina. Archives o f Environmental Contamination and Toxicology, 13: 153–162. DCN SE01840.

Sorensen, E.M.B. 1988. Selenium Accumulation, Reproductive Status, and Histopathological Changes in Environmentally Exposed Redear Sunfish. Archives of Toxicology, 61 : 324–329.

DCN SE0 1861.

Specht, W.L., D.L. Cherry, R.A. Lecleitner, and J. Cairns, Jr. 1984. Structural, Functional, and Recovery Responses of Stream Invertebrates to Fly Ash Effluent. Canadian Journal of

Fisheries and Aquatic Sciences , 41(6) : 884–896. DCN SE01848.

Stephan, C.E. 1993. Derivation of Proposed Human Health and Wildlife Bioaccumulation Factors for the Great Lakes Initiative (Draft). PB93 -154672. Environmental Research Laboratory, Office of Research and Development, Duluth, MN. ( March ). DCN SE01938.

Theis

, T.L. and R.O. Richter . 1979. Chemical Speciation of H eavy M etals in P ower P lant Ash

Pond L eachate. Environmental Science Technology , 13 : 219–224 (as cited in Simsiman et al., 1987).

Theis , T.L. and K.H. Gardner . 1990. Environmental Assessment of Ash Disp osal

. Crit Rev Environ Control, 20(1): 21–24 (as cited in Prasad et al., 1996).

Thorneloe, S.A., D.S. Kosson, F. Sanchez, A.C. Garrabrants, and G. Helms . 2010. Evaluations of

the F ate of M etals in A ir Pollution Control R esidues from Co al -F ired P ower P lants

. Environmental Science Technology, 44: 7351–7356. DCN SE01889.

Tsipoura, N., J. Burger, R. Feltes, J. Yacabucci, D. Mizrahi, C. Jeitner, and M. Gochfeld . 2008. Metal Concentrations in Three Species of Passerine Birds Breeding in the Hackensack Meadowlands of New Jersey. Environmental Research

, 107 : 218–228. DCN SE01875.

U.S. EPA. 1984. Ambient Aquatic Life Water Quality Criteria for Lead . Available online at:

< http://water.epa.gov/scitech/swguidance/standards/criteria/upload/AWQC

- for

Lead_1984.pdf > (January) . DCN SE01929.

U.S. EPA. 1986. Quality Criteria for Water 1986. EPA 440-5-86-001. Washington, DC. ( May ).

DCN SE01930.

U.S. EPA. 1996. Calculation and Evaluation of Sediment Effect Concentrations for the Amphipod Hyalella Azteca and the Midge Chironomus Riparius. Assessment and

Remediation of Contaminat ed Sediments (ARCS) Program, Great Lakes National Program

. EPA -905-R96-008. ( September ). DCN SE01931.

U.S. EPA. 1997a. Mercury Study Report to Congress Volume III: Fate and Transport of Mercury

in the Environment

. EPA -452/R-97-005. Washington, DC. ( December ) . Page B -34 . DCN

SE01932.

U.S. EPA. 1997b. Arsenic and Fish Consumption

. EPA -822-R-97-003. Washington, DC. (December). DCN SE01933.

U.S. EPA. 1998a. Non -Groundwater Pathways, Human Heath and Ecological Risk Analysis for

Fossil Fuel Combustion Phas e 2 (FFC2 ) . Draft Final Report. Washington, DC. (June). DCN

SE01934.

U.S. EPA. 1998b. Methodology for Assessing Health Risks Associated with Multiple Pathways of Exposure to Combustor Emissions. EPA 600/R-98/137. Washington, DC. ( December ).

DCN SE01935.Section 8

— References



### 8-9 U.S. EPA. 1999. Partition Coefficients for Metals in Surface Water, Soil, and Waste (Draft). Washington, DC. (June ). DCN SE01936.

U.S. EPA . 2000a. Guidance for Assessing Chemical Contaminant Data for Uses in Fish Advisories, Volume 1. EPA 823-B-00-007. Washington, DC. (November). DCN SE01922.

U.S. EPA. 2000b. Selenium Compounds (website). ( January ). Available online at: http://www.epa.gov/ttn/atw/hlthef/selenium.html . DCN SE01923.

U.S. EPA. 2000c. EPCRA Section 313 Industry Guidance: Electricity Generating Facilities

. EPA 745-B-00-004. Washington, DC. ( February ). DCN SE01924.

U.S. EPA. 2001. Fact Sheet: Drinking Water Standard for Arsenic (website). EPA 815-F-00-015 ( January ). Available online at: http://water.epa.gov/lawsregs/rulesregs/sdwa/arsenic/regulations_factsheet.cfm . DCN

SE01925.

U.S. EPA. 2005a . Partition Coefficients for Metals in Surface Water, Soil, and Waste (Final)

. EPA/600/R-05/074. Washington, DC. (July). DCN SE01892.

U.S. EPA. 2005b. Human Health Risk Assessment Protocol for Hazardous Waste Combustion

Facilities (HHRAP)

. EPA 520-R-05-006. Washington, DC. (September). DCN SE 01926.

U.S. EPA. 2006. Toxic Weighting Factor Development in Support of CWA 304(m) Planning

Process . Washington, DC. (June). EPA- HQ

- OW -2004-0032-1634. DCN SE01952.

U.S. EPA. 2007a. Framework for Metals Risk Assessment

. EPA 120/R-07/001. Washington,

DC. (March). DCN SE01927.

U.S. EPA. 2007b. Coal Combustion Waste Damage Case Assessments

. (July). DCN SE02145.

U.S. EPA. 2008a. Child -Specific Exposure Factors Handbook. EPA/600/R-06/096F. Washington, DC. (September). DCN SE01876.

U.S. EPA. 2008b. Lake Erie La kewide Management Plan 2008. DCN SE01940.

U.S. EPA. 2009a. Toxicological Review of Thallium and Compounds. Integrated Risk Information System . EPA/635/R-08/001F. Washington, DC. (September). DCN SE01907.

U.S. EPA. 2009b. Steam Electric Power Generating Poi nt Source Category: Final Detailed Study Report

. EPA 821-R-09-008. Washington, DC. (October). DCN SE00003.

U.S. EPA. 2009c. Technical Support Document for the Preliminary 2010 Effluent Guidelines Program Plan

. EPA 821-R-09-006. Washington, DC. (October). DCN SE02134.

U.S. EPA. 2009d. National Recommended Water Quality Criteria. Washington, DC. DCN

SE01908.

U.S. EPA. 2009e. National Primary Drinking Water Regulations. EPA 816-F-09-004. Washington, DC. (May). DCN SE01909.

U.S. EPA. 2010a. Provisional Peer -Reviewed Toxicity Values for Thallium and Compounds. National Center for Environmental Assessment. Superfund Health Risk Technical Support Center, Cincinnati, OH. (September) . DCN SE01941.

U.S. EPA. 2010b. Human and Ecological Risk Assessment of Coal Combustion Wastes (CCW) (Draft) . Washington, DC. (April). DCN SE01834.

U.S. EPA. 2010c. Discharge Monitoring Report (DMR) Pollutant Loading Tool: 2010 Data.

Available online at: http://cfpub.epa.gov/dmr/ . DCN SE 01959.Section 8

— References



### 8-10 U.S. EPA. 2010d. Chesapeake Bay Total Maximum Daily Load for Nitrogen, Phosphorus and Sediment. Washington, DC. (Decembe r). DCN SE 01910.

U.S. EPA. 2010e. Final Site Inspection for the Battlefield Golf Club Site, City of Chesapeake, Virginia. Washington, DC. (April). DCN SE 01948.

U.S. EPA. 2010f. Federal Register. Vol. 75, No. 118. Hazardous and Solid Waste Management System ; Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals From Electric Utilities. Washington, DC. (June). DCN SE 01953.

U.S. EPA. 2011a . Technical Factsheet on: THALLIUM. National Primary Drinking Water Regulations. Available on line at: http://water.epa.gov/drink/contaminants/basicinformation/historical/upload/Archived

Technical

- Fact

- Sheet -on- Th allium.pdf . DCN SE01911.

U.S. EPA. 2011b. Exposure Factors Handbook: 2011 Edition

. EPA/600/R-09/052F. Washington, DC. ( September ). DCN SE01912.

U.S. EPA, 2011c. Integrated Risk Information System (IRIS)

. National Center for Environmental Assessment. Washington, DC. Available online at: http://www.epa.gov/IRIS/ . DCN

SE01960.

U.S. EPA. 2011d. Technical Support Document for the 2010 Effluent Guidelines Program Plan. EPA 821-R-09-006. Washington, DC. (October). DCN SE02135.

U.S. EPA. 2011e. Office of Science & Technology Annual Report, Calendar Year 2011. EPA 820-R-12-006. Washington, DC. DCN SE01951.

U.S. EPA. 2011f. Ecological Toxicity Information (website). EPA Region 5. ( December ).

Available online at: http://www.epa.gov/R5Super/ecology/toxprofiles.htm . DCN SE01913.

U.S. EPA. 2012a . “EPA Weig hs Setting Possible First

- Time Water Quality Criteria for

Bromide.” Inside EPA

. (4 January ). DCN SE01949.

U.S. EPA. 2012b. Final Damage Case Determination Spreadsheet. Washington, DC. (18 September). DCN SE01966.

U.S. EPA, 2013a . Steam Electric Technical Questionnaire Database. Washington, DC. DCN

SE01958.

U.S. EPA, 2013b. Technical Development Document for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (EPA -821-R-13-002)

. Washington, DC. DCN SE01964.

U.S. EPA. 2013c. Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report

. DCN SE01957.

U.S. EPA. 2013d. Benefits and Cost Analysis for the Proposed Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (EPA -821-R013-004). Washington, DC. DCN SE03172.

U.S. EPA. 2013e. Impact Case Study Analysis Database. Washington, DC. DCN SE02156.

U.S. EPA and Environment Canada. 1997. Great Lakes Binational Toxics Strategy . DCN

SE01942.

U.S. EPA and Environment Canada. 2009. State of the Great Lakes 2009

. EPA 905-R-09-031.

DCN SE01939.Section 8

— References



### 8-11 U SFWS. 2008. U.S. Fish and Wildlife Service. Steps Taken to A ddress Selenium Concerns at Cane Ridge Wildlife Management Area

. News Release (13 June). DCN SE02150.

U SFWS . 2012. Selenium Threat Averted. News Release ( 19 June ). DCN SE01943.

USGS . 1995. U.S. Geological Survey. Preliminary Compilation of Descriptive Geoenvironmental Mineral Deposit Models, Chapter 2: Bioavailability of Metals . DCN

SE01937.

USGS. 2008. Environmental Contaminants in Freshwater Fish and Their Risk to Piscivorous Wildlife Based on a National Monitoring Program. Environ Monit Assess, 152: 469–494.

DCN SE01893.

Vengosh, A. 2009. The Tennessee Valley Authority's Kingston Ash Slide: Potential Water Quality Impacts of Coal Combustion Waste Storage. A Testimony to the Subcommittee on Water Resources and Environment, U.S. House of Representatives . Available online at: http://transportation.house.gov/Media/file/water/20090331/Vengosh%20Testimony.pdf

. DCN SE01864.

Villanueva, C.M., K.P. Cantor, S. Cordier, J.J.K Jaakkola, W.D. King, D.F. Lynch, S. Porru, and M. Kogevinas. 2004. Disinfection Byproducts and Bladder Cancer: A Pooled Analysis. Epidemiology, 15(3): 357–367. DCN SE01983.

WHO. 1976. World Health Organization. Environmental Health Criteria 1: Mercury. International Programme on Chemical Safety. Geneva, Switzerland. DCN SE01914.

WHO. 1987. Environmental Health Criteria 58: Selenium. International Programme on Chemical Safety. Geneva, Switzerland. DCN SE01915.

WHO. 1992. Environmental Health Criteria 135: Cadmium. International Programme on Chemical Safety. Geneva, Switzerland. DCN SE01916.

WHO. 1996. Environmental Health Criteria 182: Thallium. International Programme on Chemical Safety. Geneva, Switzerland. DCN SE01917.

WHO. 1998. Environmental Health Criteria 204: Boron. International Programme on Chemical Safety . Geneva, Switzerland. DCN SE01918.

WHO. 2001. Arsenic in Drinking Water. Available online at: <http://www.who.int/mediacentre/factsheets/fs210/en/> (20 January). DCN SE01919.

WHO. 2009. Bromide in Drinking-W ater. Background Document for Development of WHO Guidelines for Drinking- Water Quality

. WHO/HSE/WSH/09.01/6. Geneva, Switzerland.

DCN SE01920.

WHO. 2011. Manganese in Drinking-W ater. Background Document for Development of WHO

Guidelines for Drinking

- Water Quality

. WHO/HSE/WSH/03.04/104/Rev/1. Geneva,

Switzerland. DCN SE01921.Appendix A

— Literature Review Methodology and Results



# APPENDIX A

LITERATURE REVIEW ME THODOLOGY AND RESULT S

This appendix presents the methodology, resources, and summary results for the literature review. The U.S. Environmental Protection Agency (EPA) used the keyword list in

Table A-1 to identify peer

- reviewed journal articles that document environmental and human health impacts caused by steam electric discharges of the evaluated waste streams. The literature search focused on information regarding impacts caused by toxic pollutants 1 

### (e.g., metals such as arsenic, lea d, mercury, and selenium) in the discharges. EPA also searched for environmental assessments, impact studies, and related documents from state and federal governments.

In addition, the literature search involved collecting information from newspapers,

env ironmental groups, industry organizations, and other non

- peer

- reviewed information sources. These sources are considered to be “gray literature” and are not acceptable forms of formal documentation of environmental impact events. However, these literature sources can provide useful information for identifying potential areas of concern. Often, an environmental event is reported in gray literature sources before it is well documented in peer

- reviewed journals or government reports. EPA used gray literature to help highlight areas of interest and facilitate additional searches of peer

- reviewed journals for more detailed information on the impacted

area.

EPA used several different search engines to broaden the range of reference materials represented in the results. The Agency searched the following search engines in the order presented, using the keyword list in Table A-1:

• Scirus

– A comprehensive science

- specific search engine that provides access to a large database of scientific, technical, and medical journ als;

• Science Direct

– An online library that features full text journals from Elsevier, Academic Press, and other scholarly publishers;

• Ingenta

– A scholarly research database that provides access to a large collection of academic and professional research articles;

• Google Scholar

– A search engine used to find other articles that cited previously identified references as well as perform a general search of scholarly literature, including peer

- reviewed papers, theses, books, abstracts, and articles from aca demic publishers, professional societies, preprint repositories, and universities and other scholarly organizations; and

• Google – A search engine used to perform a general search of information readily

available on the Internet.

1 Under the Clean Water Act (CWA), EPA has identified 65 pollutants and classes of pollutants as toxic pollutant s, of which 126 specific substances have been designated priority toxic pollutants. See Appendix A to 40 CFR Part 423 for a list of toxic pollutants

. 

### A-1Appendix A

— Literature Review Methodology and Results



### Table A-1 . Keyword Search Terms for Environmental Impacts from

Steam Electric Power Plants

Category Keyword

Ash pond

Discharge

Lake

Landfill

Leachate

Leaks

Lotic system

Plume

Pond

Power plant

General Terms Receiving water

River

Sediment

Steam electric

Stream

Surface waters

Water

Wastewater

Water pollution

Water quality

Waste management

Wastewater discharges

Algal blooms

Attractive nuisance

B ackground levels/concentrations

Bioaccumulation

Biomagnification

Biomagnify

Contamination

Environmental impact

Environmental Terms Environmental assessment

Eutrophication

Fish

Fish consumption advisory

Fish kill

Fish mortality

Fish recover y

Hot Spot

Toxicity

Wildlife



### A-2Appendix A

— Literature Review Methodology and Results



### Table A-1 . Keyword Search Terms for Environmental Impacts from

Steam Electric Power Plants

Category Keyword

Arsenic

Arsenate

Arsenite

Boron

Boric Acid

Chloride(s)

Chromium

Magnesium

Pollutants of Concern Mercury

Metals

Methylmercury

Nitrate

Nitrogen

Selenium

Selenate

Selenite

Sulfate

Coal

Fuel Source Terms Coal combustion by

- products

Coal combustion residues

Oil

Cancer

Carcinogen

Carcinogenic

Human Health Terms Drinking water

Health effects

Human health

Toxicity

Case study

Other Terms Damage case assessment

Environmental impacts

Env ironmental aspects



### To perform the literature search, EPA paired each fuel source term (see Table A-1 ) with at least one keyword to focus the search results. Although EPA used multiple fuel source terms, the environmental impacts from the steam electric i ndustry are documented most commonly for

coal

- fired power plants. EPA used best professional judgment to create multiple keyword

combinations to further focus the literature search.

A-3Appendix A

— Literature Review Methodology and Results



### In addition to the key word combinations and search engines described above, EPA used the following supplemental methods to identify more articles for the targeted topic areas:

• 

### Reviewed references cited in previously identified published literature for additional documented cases of environmental impact;

• 

### Searched the Agency for Toxic Substances and Disease Registry’s (ATSDR) website for public health assessments and health consultations with information on the case study sites referenced in Dr. Christopher Rowe’s literature review paper published in 2002 [Rowe et al., 2002];

• 

### Sea rched for case studies of attractive nuisances unrelated to the steam electric industry using the search engines described above;

• 

### Reviewed EPA’s September 18, 2012, determination of damage cases primarily

identified in EPA’s Damage Case Assessment Report ; Environmental Integrity Project’s (EIP’s) Out of Control: Mounting Damages From Coal Ash ; EIP’s In Harm’s Way: Lack of Federal Coal Ash Regulations Endangers Americans and Their

Environment ; and Michigan’s Department of Natural Resources and Environment (M DNRE’s) Docket Comments (see Table A -3 for a full list of references); and

• 

### Searched magazines related to the steam electric industry and newspapers for articles documenting additional environmental impacts.

EPA created a database for the literature review that documents the identified literature and summarizes key information. EPA finalized the primary literature review on November 24, 2010; however, the database also includes literature identified after the primary search efforts were completed.

The foll owing tables in Appendix A summarize additional results EPA gathered from the

literature review:

• Table A-2 . Summary of Literature Review Results by Information Source;

• Table A-3 . Summary of Documented Impacts to Surface Water and Ground Water

from Steam El ectric Power Plant Discharges;

• Table A-4 . Summary of Documented Ground Water Damage Cases from Surface Impoundments;

• Table A-5 . Summary of Documented Ground Water Damage Cases from Landfills;

• Table A-6 . Summary of Documented Surface Water Damage Cases from Surface Impoundments;

• Table A-7 . Summary of Documented Surface Water Damage Cases from Landfills;

• Table A-8 . Summary of Attractive Nuisance Case Studies Related to Steam Electric Power Plants;

• Table A-9 . Summary of Attractive Nuisance Case Studies Unrela ted to Steam Electric Power Plants; and

• Table A-10. Summary of Selenium Concentrations in the Environment and Organisms Experiencing Adverse Effects.

A-4Appendix A

— Literature Review Methodology and Results



### Table A-2 highlights the results of the literature search, including documents identified by keyword searc hes and relevant documents identified from supplemental methods. Table A-3 summarizes the number of documented surface water and ground water impact cases identified during the literature search and organized by power plant. Table A-4 and Table A-5 summari ze the documented ground water impact cases from combustion residuals surface impoundments and landfills, respectively, identified during the literature search. Table A-6 and Table A-7 summarize the documented surface water impact cases from combustion res iduals surface impoundments and landfills, respectively, identified during the literature search. Table A-8 and

Table A-9 summarize attractive nuisance case studies related and unrelated to steam electric power plants, respectively. Table A-10 presents sel enium concentrations in the environment that are documented in literature as causing sublethal a nd lethal effects to organisms.

Table A-2

. Summary of Literature Review Results by Infor mation Source

Source Type Number of Documents

Identified Number of Documents

Reviewed f Number of Documents that

Discussed Environmental and Human Health Impacts

Peer

- Reviewed Literature a 151 128 117

Government Publication b 53 47 32

University Resear ch c 13 12 9

Gray Literature d 18 16 14

Industry Publication e 4 3 3

Total 239 206 175

Source: ERG, 2013b.

a – Peer

- reviewed literature consists of journal articles that undergo a formal review process prior to publishing.

b

– Government publications a re documents affiliated with state or federal government agencies.

c – University research includes finalized dissertations and theses, as well as papers published on behalf of a university or presented at a conference.

d – Gray literature includes docum ents that are subjected to a less stringent review process (e.g., newspaper articles, environmental group publications).

e – Industry publications include documents prepared by or for industry

- affiliated entities.

f

– Several documents were not reviewed as part of the formal literature review either because EPA was unable to acquire the full text of the document for review or because once the full text document was obtained a preliminary review determined the document was not appropriate for inclusion in th e literature review.



### A-5Appendix A

— Literature Review Methodology and Results



### Table A-3. Summary of Documented Impacts to Surface Water and Ground Water from Steam Electric Power Plant DischargesA-6 Plant Name Number of Documented

Surfac e Water Case Studies and Damage Cases Number of Documented

Ground Water Case Studies and Damage Cases A.B. Brown Generating Station, Southern Indiana Gas and Electric Company (SIGECO) (IN) 0 1 b

Allen Steam Generating Plant, Duke Power (NC) 0 1 b

Alma St ation, Dairyland Power (WI) 0 2 b

Asheville Steam Electric Plant, Progress Energy (NC) 0 1 b

B.C. Cobb Power Plant, Consumers Energy (MI) i 0 2 c
Bailly Generating Station, Northern Indiana Public Service Company (NIPSCO) (IN) i 0 2 b

Belews Creek Steam Stat ion, Duke Energy (NC) 13 a,b,d 1 b

Belle River Power Plant, Detroit Edison Company (MI) i 1 c 1 c
Big Bend Station, Tampa Electric Company (FL) 1 b 1 b

Big Cajun 2 Power Plant, NRG Energy/Louisiana Generating, LLC (LA) 0 1 b

Brandon Shores, Constellation Energ y (MD) i 0 1 d

Brayton Point Station, Dominion (MA) i 0 1 b

Bruce Mansfield Power Plant, First Energy (PA) 1 b 1 b

Bull Run Steam Plant, Tennessee Valley Authority (TVA) (TN) 1 b 0
C.D. McIntosh, Jr. Power Plant, City of Lakeland (FL) 0 1 b

C.R. Huntley Gener ating Station, NRG Energy (NY) i 0 1 b

Canadys Plant, South Carolina Electric & Gas (SCE&E) (SC) 0 1 b

Cape Fear Steam Plant, Progress Energy (NC) 0 1 b

Cardinal Plant, American Electric Power (AEP) (OH) 1 b 1 b

Cayuga Generating Station, Duke Energy (NY) i 1 b 1 b

Chesapeake Energy Facility, Dominion Power (VA) 0 1 f

Cholla Steam Electric Generating Station, Arizona Public Service Company (AZ) 0 1 b

Clifty Creek Station, Indiana Kentucky Electric Company (IKEC) (IN) 0 1 b

Clinch River Plant, American Electric Power (AEP)/Appalachian Power (VA) 1 b 0
Coal Creek Station, Cooperative Power Association/United Power (ND) 0 1 b

Coffeen Power Station, Ameren (IL) i 0 1 b

Colbert Fossil Plant, Tennessee Valley Authority (TVA) (AL) 0 1 b

Colstrip Power Plant, PPL Montana (MT) 0 1 b

Columbia Electric Generating Station (WI) 5 a 0
Columbia Energy Center, Alliant Energy (WI) 1 b 0Appendix A

— Literature Review Methodology and Results



### Table A-3. Summary of Documented Impacts to Surface Water and Ground Water from Steam Electric Power Plant DischargesA-7 Plant Name Number of Documented

Surfac e Water Case Studies and Damage Cases Number of Documented

Ground Water Case Studies and Damage Cases Conesville Power Plant, American Electric Power (AEP) (OH) 0 1 b

Cumberland Steam Plant, Tennessee Valley Authority (TVA) (TN) 0 1 b

Curtis Stanto n Energy Center, Orlando Utility Commission (FL) 1 b 1 b

Dan River Steam Station, Duke Energy (NC) 0 1 b

Danskammer Generating Station, Dynergy (NY) i 0 1 b

D

- Area Coal

- Fired Power Plant, Savannah River Site (SRS) (SC) 24 a,b 0
Dave Johnston Power Plant (WY) 0 1 b

Dickerson Generating Station, Mirant (MD) 1 f 1 g

Dolet Hills Power Station, Central Louisiana Electric Co

- Op (CLECO) Power, LLC (LA) 0 1 b

Duck Creek Station, Central Illinois Light Company (IL) 0 1 b

Dunkirk Generating Station, NRG Energy (NY) i 0 1 b

E.J. Stoneman Generating Station, Dairyland Power Cooperative (WI) 0 1 b

East Bend Generating Station, Cinergy (KY) 0 1 b

Edgewater Generating Station, Alliant Energy (WI) i 0 1 b

Elrama Power Plant, Reliant Energy (PA) i 1 b 1 b

Erickson Station, Lansing Board of Water & Light (MI) i 0 1 b

Escanaba Generating Station, Integrys (MI) i 1 c 1 c
Fayette Power Project, Lower Colorado River Authority (TX) 1 b 1 b

Flint Creek Power Plant, American Electric Power (AEP)/South West Electric Power Company (SWEPCO) (AR) 0 1 b

Gallatin Fossil Plant, Tennesee Valley Authority (TVA) (TN) 1 b 1 b

General James M. Gavin Power Plant, American Electric Power/Ohio Power Company (OH) 1 b 1 b

George Neal Station North, Berkshire Hathaway/MidAmerican Energy Company (IA) 0 1 b

George Ne al Station South, Berkshire Hathaway/MidAmerican Energy Company (IA) 0 1 b

Gibson Generating Station, Duke Energy (IN) 5 a,b 1 b

Glen Lyn Plant, American Electric Power (AEP)/Appalachian Power (VA) 6 a,b 0 Grainger Generating Station, Santee Cooper/South Ca rolina Public Service Authority (SCPSA) (SC) 0 1 b

Harbor Beach Power Plant, Detroit Edison Company (MI) i 1 c 1 c
Hatfield's Ferry Power Station, Allegheny Energy (PA) 1 b 1 b

Havanna Power Plant, Illinois Power Company (IL) 0 1 bAppendix A

— Literature Review Methodology and Results



### Table A-3. Summary of Documented Impacts to Surface Water and Ground Water from Steam Electric Power Plant DischargesA-8 Plant Name Number of Documented

Surfac e Water Case Studies and Damage Cases Number of Documented

Ground Water Case Studies and Damage Cases Hennepin Power Station, Ill inois Power Company (IL) 0 1 b

Herbert A. Wagner, Constellation Energy (MD) i 0 1 d

Hunlock Power Station, UGI Development Company (PA) 1 b 1 b

Hutsonville Power Station, Central Illinois Public Service Company (IL) 0 1 b

Independence Steam Station, Entergy/ Arkansas Power and Light (AR) 0 1 b

Indian River Generating Station, NRG Energy (DE) 1 b 1 b

J.H. Campbell Power Plant, Consumers Energy (MI) 1 c 1 c
J.R. Whiting Generating Plant, CMS/Consumers Energy (MI) 1 b 0
John Amos Plant, American Electric Power (AEP )/Appalachian Power (WV) 1 b 0
John Sevier Fossil Plant, Tennessee Valley Authority (TVA) (TN) i 2 b 2 b

Johnsonville Fossil Plant, Tennessee Valley Authority (TVA) (TN) 1 b 1 b

Joliet Generating Station 9, Midwest Generation (IL) 0 1 b

Karn/Weadock Generatin g Facility, Consumer Energy (MI) 1 b 1 b

Kingston Fossil Plant, Tennessee Valley Authority (TVA) (TN) 7 a,h 1 h

Lansing Smith Plant, Florida Power and Light (FL) 0 1 b

Lee Steam Plant, Progress Energy (NC) 0 1 b

Leland Olds Station, Basin Electric Power Coop erative (ND) 0 1 b

Marion Plant, Southern Illinois Power Cooperative (IL) 1 b 1 b

Martin Lake Steam Station, Texas Utilities Electric Service Company (TX) 9 a,b 0
Martin's Creek Power Plant, PPL (PA) 1 i 0 i

Marysville Power Plant, Detroit Edison Company (MI ) i 1 c 1 c
Merom Generating Station, Hoosier Energy (IN) 0 1 b

Miamiview Landfill, Cincinnati Gas & Electric Company (OH) j 0 1 b

Michigan City Generating Station, Northern Indiana Public Service Company (NIPSCO) (IN) i 0 1 b

Mill Creek Plant, E ON U.S./Louis ville Gas & Electric (LG&E) (KY) 0 1 b

Mitchell Power Station, Allegheny Energy (PA) 1 b 1 b

Montville Generating Station, NRG Energy/Montville Power, LLC (CT) 0 1 b

Morgantown Generating Station (MD) 1 1 b

Muscatine Generating Station, Muscatine Power & Wa ter (IA) i 0 1 b

Muskingum River Plant, American Electric Power (AEP)/ Ohio Power Company (OH) 1 b 1 bAppendix A

— Literature Review Methodology and Results



### Table A-3. Summary of Documented Impacts to Surface Water and Ground Water from Steam Electric Power Plant DischargesA-9 Plant Name Number of Documented

Surfac e Water Case Studies and Damage Cases Number of Documented

Ground Water Case Studies and Damage Cases Nelson Dewey Generating Station, Alliant Energy (WI) i 0 1 b

Northeastern Station, American Electric Power/Public Service Company Oklahoma (OK) 1 b 1 b

Oak C reek Power Plant, Wisconsin Energy (WE Energies (WE))/Wisconsin Electric Power Company (WI) 0 1 b

Oak Ridge Y

- 12 Plant, Department of Energy (TN) 4 a,b 1 b

Panda Brandywine L.P. (MD) i 1 b 1 b

Petersburg Generating Station, Indiana Power & Light (IN) 0 1 b

Ph illips Power Plant, Duquesne Light Company (PA) 0 1 b

Pirkey Power Plant, Southwestern Electric Power Company (SWEPCO) (TX) 2 a,b 0
Plant Bowen, Georgia Power (GA) 1 b 0
Port Washington Facility, Wisconsin Electric Power Company (WEPCO) (WI) 0 2 b

Portland Generating Station, RRI Energy (PA) 1 b 1 b

Powerton Plant, Commonwealth Edison (IL) 1 1 b

Presque Isle Power Plant, WE Energies (WE) (MI) 0 1 c
Pulliam Power Plant, Wisconsin Public Service Corp. (WI) i 0 1 b

R.M. Heskett Station, Montana

- Dakota Utilities (ND) 0 1 b

R.M. Schahfer Generating Station (IN) 0 1 b

Reid Gardner Generating Facility, Nevada Energy (NV) 0 1 b

Riverbend Steam Plant, Duke Energy (NC) 3 d 0
Rock River Generating Station, Alliant Energy (WI) i 0 1 b

Rodemacher Power Station, Central Loui siana Electric Co

- Op (CLECO) Power, LLC (LA) 1 b 1 b

Roxboro Plant, Progress Energy (NC) 7 a,b,d 0
Saint Clair Power Plant, Detroit Edison Company (MI) i 1 c 1 c
Salem Harbor Station, Dominion (MA) i 0 1 b

Seminole Generating Station, Seminole Electric Coopera tive (FL) 1 b 1 b

Seward Generating Station, RRI Energy (PA) 1 b 1 b

Shawnee Fossil Plant, Tennessee Valley Authority (TVA) (KY) 1 b 1 b

Sheldon Station, Nebraska Public Power District (NE) 0 1 b

Sherburne County (Sherco) Generating Plant, Xcel Energy/Souther n Minnesota Municipal Power Agency (MN) 1 b 1 bAppendix A

— Literature Review Methodology and Results



### Table A-3. Summary of Documented Impacts to Surface Water and Ground Water from Steam Electric Power Plant DischargesA-10 Plant Name Number of Documented

Surfac e Water Case Studies and Damage Cases Number of Documented

Ground Water Case Studies and Damage Cases Shiras, Marquette Board of Light & Power (MI) i 0 1 c
Spurlock Station, Eastern Kentucky Power Cooperative (KY) 0 1 b

Sutton Steam Plant, Progress Energy (NC) 0 1 b

Swift Creek Structural Fill, ReUse Technology , Inc./ Full Circle Solutions (NC) j 0 1 b

Urquhart Station, South Carolina Electric & Gas Company (SGE&E) (SC) 0 1 b

Valley Power Plant, Wisconsin Energy (WI) i 0 1 b

Venice Power Station, Union Electric Company/Ameren Energy/AmerenUE (IL) 0 1 b

Vermillion Power Station, Illinois Power (IL) 0 1 b

W.C. Beckjord Station, Duke Energy (formerly Cinergy) (OH) 0 1 b

W.J. Neal Station, Basin Electric Power Cooperative (ND) 1 b 1 b

Wateree Station, SCE&G (SC) 0 1 b

Welsh Power Plant, Southwestern Electric Power Compa ny (SWEPCO) (TX) 3 a,b 0
Westover Generating Plant, AES (NY) i 0 1 b

Widows Creek Fossil Plant, Tennessee Valley Authority (TVA) (AL) 0 1 b

Wood River Power Station, Illinois Power Company (IL) 0 1 b

Yorktown Power Station, Virginia Electric Power and Power Company (VEPCO) (VA) 0 1 b

Total 132 l 123 l

Source: U.S. EPA, 2012b; U.S. EPA, 2013e.

a – ERG, 2012b.

b – U,S. EPA, 2007b; EIP et al., 2010a; EIP et al., 2010b.

c – MDNRE, 2010.

d – Ruhl, 2012.

e – MACo, 2007.

f

– U.S. EPA, 2010e.

g – Gazette, 2011.

h – A ECOM, 2009; ASU, 2009.

i

– DRBC, 2006.
j

– The damage case source did not specifically identify the plant name; therefore, EPA assumed the plant name based on available literature and proximity of the plant to the damage case site.

k – EPA was unable to identify the steam electric power plant associated with this damage case. For the purpose of counting the unique number of plan ts, these damages were assumed to be associated with a plant not already identified in the damage cases.

l

– One case study or damage case may document impacts to both ground water and surface water.Appendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-11 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Allen Steam Generating Plant, Duke Power (NC) Bottom Ash, Fly Ash Arsenic, Manganese, Iro n, pH, Barium X X U.S. EPA,

2007b Asheville Steam Electric Plant, Progress Energy (NC) Ash Boron, Chromium, Iron, Manganese X X EIP et al.,

2010a Bailly Generating Station,

Northern Indiana Public Service Company (NIPSCO) (IN) Ash Arsenic, Lead, Cadm ium X U.S. EPA,

2007b

Bangor Quarry Ash Disposal Site, Portland Generating Station, RRI Energy (PA) Bottom Ash, Fly Ash,

Other Selenium, Arsenic, Barium, Boron, Cadmium, Hexavalent Chromium, Potassium, pH, Iron, Manganese, Sulfate, TDS, Aluminum, Fluor ide,

Chlorides X X EIP et al.,

2010a

Belews Creek Steam Station, Duke Energy (NC) Fly Ash,

FGD Selenium, Mercury, Arsenic, Barium, Boron, Cadmium, Copper, Chromium, Chloride, Fluoride, Iron, Lead, Manganese, Nitrate, Silver, Zinc, Sulfate, TDS, TOH,

TOC , pH X X X X EIP et al.,

2010a

Big Bend Station, Tampa Electric Company (FL) Bottom Ash, Fly Ash, FGD, Other Arsenic, Aluminum, Boron, Chloride, Fluoride, Iron, Manganese, Molybdenum, Sulfate, Sodium, Thallium, Gross Alpha, TDS X X X EIP et al.,

2010a

B ig Cajun 2 Power Plant, NRG Energy/Louisiana Generating, LLC (LA) Bottom Ash, Fly Ash,

Other Selenium, TDS, Calcium X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-12 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source C.D. McIntosh, Jr. Power Plant, City of Lakeland (FL) Bottom Ash, Fly Ash,

FGD Selenium, Arsenic, Cadmium, Lead,

Ma nganese, Vanadium, Nitrate, Iron, Sulfate, TDS, pH X EIP et al.,

2010b

Canadys Plant, South Carolina Electric & Gas (SCE&E) (SC) Ash Arsenic, Nickel X U.S. EPA,

2007b Cape Fear Steam Plant, Progress Energy (NC) Ash Lead, Chromium, Boron, Iron, Mang anese, Sulfate X X X EIP et al.,

2010a Cardinal Fly Ash Reservoir (FAR) 1 and 2, American Electric Power (AEP) (OH) Bottom Ash, Fly Ash,

FGD Arsenic, Boron, Molybdenum X X X X EIP et al.,

2010b

Cayuga Coal Ash Disposal Landfill, AES (NY) Bottom Ash, Fly Ash,

Other Selenium, Arsenic, Boron, Cadmium, Lead, TDS, Aluminum, Manganese,

Sulfate X X X EIP et al.,

2010b

Cholla Steam Electric Generating Station, Arizona Public Service Company (AZ) Fly Ash Sulfate, TDS, Chloride,

Fluoride X U.S. EPA,

2007b

Cl ifty Creek Station, Indiana Kentucky Electric Company (IKEC) (IN) Fly Ash,

Other Boron, Manganese, Iron,

Sulfate X X EIP et al.,

2010a

Coal Creek Station Surface Impoundments, Cooperative

Power Association/United Power (ND) Ash Selenium, Arsenic, Sulfat e, Chloride, Boron X U.S. EPA,

2007b

Colbert Fossil Plant, Tennessee Valley Authority (TVA) (AL) Ash, Other Selenium, Sulfate,

Chromium X U.S. EPA,

2007b Colstrip Power Plant, PPL Montana (MT) Bottom Ash, Fly Ash,

FGD Selenium, Boron, Sulfate, TDS, Molybdenum X X EIP et al.,

2010aAppendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-13 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Cumberland Steam Plant, Tennessee Valley Authority (TVA) (TN) Bottom Ash, Fly Ash Selenium, Arsenic, Aluminum, Boron, Chlorides, Iron, Manganese, Sulfate, and TDS X EIP et al.,

2010b

Curtis Stanton Energy Center,

Or lando Utility Commission (FL) Bottom Ash, Fly Ash, FGD, Other Aluminum, Beryllium, Calcium, Chloride, Iron, Manganese, Sodium, Sulfates, TDS, Vanadium, Gross Alpha, Radium -226, pH X EIP et al.,

2010a

Dan River Steam Station, Duke Energy (NC) Bottom Ash

, Fly Ash,

Other Chromium, Iron, Lead, Manganese, Silver, Sulfate X EIP et al.,

2010b

Dolet Hills Power Station,

Central Louisiana Electric Co

Op (CLECO) Power, LLC (LA) Bottom Ash, Fly Ash, FGD, Other Selenium, Arsenic, Lead, Chlorides, TDS, Sulfate, Iron, pH, Alkalinity,

Calcium X X EIP et al.,

2010b

Duck Creek Station, Central Illinois Light Company (IL) Not Specified Sulfate, TDS, Chloride, Manganese, Iron X U.S. EPA,

2007b E.J. Stoneman Generating Station, Dairyland Power Cooperative (WI) As h, Other Cadmium, Chromium, Sulfate, Manganese, Iron,

Zinc X X U.S. EPA,

2007b

Fayette Power Project (Sam Seymour), Lower Colorado River Authority (TX) Bottom Ash, Fly Ash, FGD, Other Selenium, Arsenic, Aluminum, Chlorides, Cobalt, Manganese, Molybdenum , Sulfate, TDS X X X EIP et al.,

2010b

Flint Creek Power Plant,

American Electric Power (AEP)/South West Electric Power Company (SWEPCO) (AR) Bottom Ash, Fly Ash,

Other Selenium, Barium, Boron, Cadmium, Chromium, Iron, Lead, Manganese, pH, Silver, Sulfat e, TDS X X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-14 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Gallatin Fossil Plant, Tennessee Valley Authority (TVA) (TN) Bottom Ash, Fly Ash Aluminum, Boron, Beryllium, Cadmium, Iron, Manganese, Nickel, Sulfate,

TDS X X X X EIP et al.,

2010b

General James M. Gavin Power Plant, Amer ican Electric Power/Ohio Power Company (OH) Bottom Ash, Fly Ash, FGD, Other Arsenic, Alpha Activity, Barium, Cadmium, Lead, Molybdenum, Sulfate, TDS, Aluminum, Copper, Nickel,

Zinc X X X EIP et al.,

2010b

Gibson Generating Station, Duke Energy (IN) Botto m Ash, Fly Ash Selenium, Arsenic, Boron, Manganese, Iron X X X EIP et al.,

2010a Grainger Generating Station, Santee Cooper/South Carolina Public Service Authority (SCPSA) (SC) Fly Ash Arsenic X EIP et al.,

2010a

Havanna Power Plant, Illinois

Power C ompany (IL) Ash Manganese, Sulfate X U.S. EPA,

2007b Hennepin Power Station, Illinois Power Company (IL) Not Specified Sulfate, TDS X U.S. EPA,

2007b Hunlock Power Station, UGI Development Company (PA) Ash Arsenic, Iron, Manganese, Barium, Boron, L ithium X X X X EIP et al.,

2010a Hutsonville Power Station,

Central Illinois Public Service Company (IL) Not Specified Sulfate, TDS X U.S. EPA,

2007b

Independence Steam Station, Entergy/Arkansas Power and Light (AR) Bottom Ash, Fly Ash,

Other Selenium , Cadmium, Iron, Lead, Manganese, pH, Sulfate, TDS, Strontium,

Boron X X EIP et al.,

2010b

J.H. Campbell, Consumers Energy (MI) Not Specified Selenium, Boron, Lithium, Antimony MDNRE,

2010 John Sevier Fossil Plant, Tennessee Valley Authority (TVA) (TN) Bottom Ash, Fly Ash Arsenic, Aluminum, Cadmium, Manganese, Boron, Strontium, Sulfate X X X X EIP et al.,

2010aAppendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-15 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Johnsonville Fossil Plant, Tennesee Valley Authority (TVA) (TN) Bottom Ash, Fly Ash Arsenic, Aluminum, Boron, Cadmium, Chromium, Chlorides, TDS, Iron, Lead, Manganese, Molybdenum,

Sulfate X X EIP et al.,

2010b

Karn/Weadock Generating Facility, Consumer Energy (MI) Ash Mercury, Arsenic, Boron, Lithium, Phosphorus X X EIP et al.,

2010a Kingston Fossil Plant, Tennessee Valley Authority (TV A) (TN) Fly Ash Selenium, Arsenic, Barium, Cadmium, Lead X X X AECOM, 2009; ASU,

2009 Lansing Smith Plant, Florida Power and Light (FL) Fly Ash Aluminum, Cadmium, Chloride, Chromium, Fluoride, Sulfate, Manganese, Iron, Radium

226, Radium

- 228, TDS X U. S. EPA,

2007b

Lee Steam Plant, Progress Energy (NC) Ash Arsenic, Lead, Boron, Manganese, Iron X X X EIP et al.,

2010a

Leland Olds Station Basin Electric Power Cooperative (ND) Bottom Ash, Fly Ash,

Other Selenium, Arsenic, Boron, Iron, Lead, Sulfate, TDS X EIP et al.,

2010b

Lincoln Stone Quarry Landfill, Joliet Generating Station 9, Midwest Generation (IL) Bottom Ash,

Other Arsenic, Ammonia, Boron, Chlorides, Fluoride, Manganese, Molybdenum, pH, Sodium, Sulfate, TDS, Barium, Copper, Nitrate X X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-16 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source

Little Blue Run Surface Impoundment, Bruce Mansfield Power Plant, First Energy (PA) Bottom Ash, Fly Ash,

FGD Selenium, Arsenic, Aluminum, Antimony, Barium, Boron, Cadmium, Calcium, Chloride, Hexavalent Chromium, Fluoride, Iron, Lead, Mangan ese, pH, Sodium, Sulfate, TDS, TSS, Thallium, Turbidity X X X EIP et al.,

2010b

Marion Plant, Southern Illinois Power Cooperative (IL) Bottom Ash, Fly Ash,

FGD Boron, Cadmium, Iron, Aluminum, Manganese X X X X EIP et al.,

2010b

Michigan City Site (IN) A sh Arsenic X U.S. EPA,

2007b Mill Creek Plant, E ON

U.S./Louisville Gas & Electric (LG&E) (KY) Bottom Ash, Fly Ash, FGD, Other Arsenic, Chlorides, Sodium, Sulfate, TDS X X EIP et al.,

2010b

Mitchell Power Station, Allegheny Energy (PA) Bottom Ash,

F ly Ash Arsenic, Ammonia, Boron, Calcium, Chlorides, Iron, Molybdenum, Magnesium, Manganese, Nickel, Potassium, Sodium, Sulfate, Total Alkalinity, TDS X X X EIP et al.,

2010a

Montville Generating Station, NRG Energy/Montville Power, LLC (CT) Bottom Ash,

F ly Ash Arsenic, Beryllium, Cadmium, Copper, Iron, Lead, Manganese, Nickel, pH X X X EIP et al.,

2010b

Morgantown Generating Station,

Faulkner Off

- site Disposal Facility (MD) Bottom Ash, Fly Ash,

Other Iron, pH X X U.S. EPA,

2007b

Muskingum River Plant

, American Electric Power (AEP)/ Ohio Power Company (OH) Bottom Ash, Fly Ash Arsenic, Barium, Iron,

Sulfate X X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-17 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Nelson Dewey Ash Disposal Facility, Alliant (formerly Wisconsin Power & Light) (WI) Ash Selenium, Arsenic, Sulfate,

Boron , Fluoride U.S. EPA,

2007b

Oak Ridge Y

- 12 Plant, Chestnut Ridge Operable Unit 2, Oak Ridge Reservation, Department of Energy (TN) Bottom Ash, Fly Ash Selenium, Arsenic, Lead, Aluminum, Iron, Barium, Cobalt, Magnesium, Zinc, Copper, Calcium, Manganese, Potassium, Thallium, Sodium X X U.S. EPA,

2007b

Phillips Power Plant Landfill, Duquesne Light Company (PA) Ash, FGD TDS, Chlorides, Sodium, Fluoride, Manganese, Aluminum, Sulfate X X EIP et al.,

2010a

Reid Gardner Generating Facility, Nevada Energy (NV) Fly Ash,

FGD Selenium, Arsenic, Chloride, Sulfate, TDS, Nitrate, Boron, Chromium, Manganese, Magnesium, Molybdenum, Sodium, Vanadium, Titanium X X X EIP et al.,

2010a

Rodemacher Power Station,

Central Louisiana Electric Co

Op (CLECO) Power, LLC (LA ) Bottom Ash, Fly Ash,

Other Arsenic, Lead, pH, TDS, Specific Conductance, Chlorides, Sulfate X X X EIP et al.,

2010b

Seminole Generating Station, Seminole Electric Cooperative (FL) Fly Ash, FGD, Other Arsenic, Chlorides, Sulfates, Iron, TDS, Boron,

Alum inum, Lead, Sodium X X X EIP et al.,

2010a

Seward Generating Station, RRI Energy (PA) Ash, Other Selenium, Arsenic, Aluminum, Antimony , Cadmium, Chlorides, Chromium, Iron, Lead, Manganese, Nickel, pH, Sulfate, TDS, Turbidity, Zinc, Sodium, Calcium,

Bari um, Boron, Fluoride, Magnesium X X X EIP et al.,

2010aAppendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-18 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Shawnee Fossil Plant, Tennessee Valley Authority (TVA) (KY) Bottom Ash, Fly Ash Selenium, Arsenic, Boron, pH, Sulfate, TDS X X X EIP et al.,

2010b Sherburne County (Sherco) Generating Plant, Xcel

E nergy/Southern Minnesota Municipal Power Agency (MN) Bottom Ash, Fly Ash,

FGD Arsenic, Cadmium, Chromium, Fluoride, Lead, Nitrate, Chloride, Copper, Iron, Manganese, Sulfate,

Zinc X X U.S. EPA,

2007b

Spurlock Station, Eastern Kentucky Power Cooperative (KY) Bottom Ash, Fly Ash,

FGD Arsenic, Sulfate, Iron, TDS X X EIP et al.,

2010b

Sutton Steam Plant, Progress Energy (NC) Fly Ash Arsenic, Boron, Manganese,

Iron X X X EIP et al.,

2010a Urquhart Station, South Carolina Electric & Gas Company (SGE&E) (S C) Ash Arsenic, Nickel X EIP et al.,

2010a

Venice Power Station Ash Ponds, Union Electric Company/Ameren Energy/AmerenUE (IL) Bottom Ash, Fly Ash,

Other Arsenic, Boron, Cadmium, Iron, Manganese, TDS X X X EIP et al.,

2010b

Vermillion Power Station,

I llinois Power (IL) Not Specified Sulfate, TDS X X U.S. EPA,

2007b W.C. Beckjord Station, Duke Energy (formerly Cinergy) (OH) Ash Selenium, Sulfate X X U.S. EPA,

2007b

W.J. Neal Station Surface Impoundment, Basin Electric Power Cooperative (ND) Fly As h, FGD, Othe Selenium, Arsenic, Antimony, Chromium, Manganese, Sodium, Cadmium, Lead, Zinc X U.S. EPA,

2007b

Wateree Station, SCE&G (SC) Bottom Ash, Fly Ash Arsenic X X EIP et al.,

2010a Weber Ash Disposal Site, AES Creative Resources (NY) Ash Sulfa te, TDS, Manganese, Iron, Aluminum, pH X U.S. EPA,

2007bAppendix A

— Literature Review Methodology and Results



### Table A-4

. Summary of Documented Ground Water Damage Cases from Surface ImpoundmentsA-19 Case Study Site a Type of

Wa stes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Westland Disposal Site, Dickerson Generating Station, Mirant (MD) Fly Ash Selenium, Arsenic, Barium, Chromium, Cobalt, Copper, Iron, Zinc X Gazette,

2011

Widows Creek Fossil Plant,

Tennessee Valley Authority (TVA) (AL) Not Specified Lead, Cadmium, Chromium X U.S. EPA,

2007b

Wood River Power Station, Illinois Power Company (IL) Not Specified Sulfate, TDS, Chloride, Manganese, Iron X U.S. EPA,

2007b Yorktown Power Station,

Chisman Creek Disposal Site, Virginia Electric Power and Power Company (VEPCO) (VA) Fly Ash Arsenic, Vanadium, Sulfate, Beryllium, Chromium, Copper, Molybdenum, Nickel,

Vanadium X U.S. EPA,

2007b

Acronyms: FGD (Flue Gas Desulfurization); MCL (Maximum Contaminant Le vel); TDS (Total Dissolved Solids); WQC (Water Quality Criteria).

a – This damage case listing is based on a subset of the damage cases that were reviewed by EPA [U.S. EPA, 2012b; U.S. EPA, 2013e ].

b

– The term “ash” was used when the impact case study source did not identify the type of ash present at the waste management unit.

c – An “X” indicates that one or more of the pollutants listed exceeded MCLs or federal/state WQC/standards.

d – An “X” indicates that the ground water contaminated the surface wate r with one or more of the pollutants listed.

e – An “X” indicates that the ground water contaminated a source outside the plant property boundaries.Appendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-20 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source

A.B. Brown Generatin g Station,

Southern Indiana Gas and Electric Company (SIGECO) (IN) Not Specified Sulfate, TDS, Chlorides, pH X U.S. EPA,

2007b

Alma Off

- Site Fly Ash Landfill, Dairyland Power (WI) Fly Ash Sulfate, Manganese, Boron U.S. EPA,

2007b

Alma On

- Si te Fly Ash Landfill, Dairyland Power (WI) Fly Ash Sulfate, Manganese U.S. EPA,

2007b Bangor Quarry Ash Disposal Site, Portland Generating Station, RRI Energy (PA) Bottom Ash, Fly Ash,

Other Selenium, Arsenic, Barium, Boron, Cadmium,

Hexavalent Chr omium, Potassium, pH, Iron, Manganese, Sulfate, TDS, Aluminum, Fluoride,

Chlorides X X EIP et al.,

2010a

Battlefield Golf Club, Chesapeake Energy Facility, Dominion Power (VA) Fly Ash Arsenic X EPA, 2010e

BBSS Sand and Gravel Quarries,

Constell ation Energy (MD) Fly Ash Arsenic, Selenium, Aluminum, Cadmium, Thallium, Manganese,

Sulfate X MACo,

2007

B.C. Cobb, Consumers Energy (MI) Not Specified Boron , Lithium MDNRE,

2010 Belews Creek Steam Station, Duke Energy (NC) Fly Ash,

FGD Selenium , Mercury, Arsenic, Barium, Boron, Cadmium, Copper, Chromium, Chlorides, Fluoride, Iron, Lead, Manganese, Nitrate, Silver, Zinc, Sulfate, TDS, pH X X X X EIP et al.,

2010aAppendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-21 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Big Bend Station, Tampa Electric Company (FL) Bottom Ash, Fly Ash, FGD, Other Arsen ic, Aluminum, Boron, Chlorides, Fluoride, Iron, Manganese, Molybdenum, Sulfate, Sodium, Thallium, Gross Alpha, TDS X X X EIP et al.,

2010a

Brandywine Coal Ash Landfill,

Mirant Mid

- Atlantic (LLC) Bottom Ash, Fly Ash Selenium, Cadmium, Lead, Manganese, Ir on, Aluminum, Sulfate, TDS,

Chlorides X X X EIP et al.,

2010a

C.D. McIntosh, Jr. Power Plant, City of Lakeland (FL) Bottom Ash, Fly Ash,

FGD Selenium, Arsenic, Cadmium, Lead, Manganese, Vanadium, Nitrate, Iron, Sulfate, TDS, pH X EIP et al.,

2010b

C.R. Huntley Flyash Landfill (NY) Fly Ash Arsenic, Iron, Manganese, Sulfate, TDS X U.S. EPA,

2007b Cardinal Fly Ash Reservoir (FAR) 1 and 2, American Electric Power (AEP) (OH) Bottom Ash, Fly Ash,

FGD Arsenic, Boron, Molybdenum X X X X EIP et al.

, 2010b

Cayuga Coal Ash Disposal Landfill, AES (NY) Bottom Ash, Fly Ash,

Other Selenium, Arsenic, Boron, Cadmium, Lead, TDS, Aluminum, Manganese,

Sulfate X X X EIP et al.,

2010b

CCW Landfill, Trans

- Ash, Inc. (TN) Bottom Ash, Fly Ash Mercury, Iron, Boro n, Sulfate X X EIP et al.,

2010a

Cedar

- Sauk Landfill, Wisconsin Electric Power Company (WEPCO) (WI) Ash Selenium, Sulfate, Boron X U.S. EPA,

2007b

Clifty Creek Station, Indiana Kentucky Electric Company (IKEC) (IN) Fly Ash,

Other Boron, Mangane se, Iron,

Sulfate X X EIP et al.,

2010aAppendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-22 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Coal Ash Pit #3, Sheldon Station, Nebraska Public Power District (NE) Bottom Ash, Fly Ash Selenium, Sulfate X X EIP et al.,

2010b

Coal Combustion Waste Landfill, Merom Generating Station, Hoosier Energy (IN ) Ash Barium, Chromium, Cadmium, Lead, Sulfate,

Chlorides X U.S. EPA,

2007b

Colstrip Power Plant, PPL Montana (MT) Bottom Ash, Fly Ash,

FGD Selenium, Boron, Sulfate, TDS, Molybdenum X X EIP et al.,

2010a

Conesville Fixed FGD Sludge Landfill, Am erican Electric Power (AEP) (OH) Fly Ash,

FGD Arsenic, Cadmium, Chromium, Calcium, Magnesium, TDS, Sulfate,

Iron X U.S. EPA,

2007b

Curtis Stanton Energy Center, Orlando Utility Commission (FL) Bottom Ash, Fly Ash, FGD, Other Aluminum, Beryllium,

Cal cium, Chlorides, Iron, Manganese, Sodium, Sulfate, TDS, Vanadium, Gross Alpha, Radium -226, pH X EIP et al.,

2010a

Dan River Steam Station, Duke Energy (NC) Bottom Ash, Fly Ash,

Other Chromium, Iron, Lead, Manganese, Silver, Sulfate X EIP et al

., 2010b

Danskammer Waste Management Facility, Central

Hudson Gas and Electric Corporation (NY) Fly Ash Selenium, Arsenic, Sulfate, Sulfide, TDS, Turbidity, Iron, Magnesium, Manganese, Sodium, Boron, pH X U.S. EPA,

2007b

Dave Johnston Power Plant ( WY) Fly Ash Cadmium, Manganese, Sulfate, Boron X U.S. EPA,

2007b Dolet Hills Power Station,

Central Louisiana Electric Co

Op (CLECO) Power, LLC (LA) Bottom Ash, Fly Ash, FGD, Other Selenium, Arsenic, Lead, Chlorides, TDS, Sulfate, Iron, pH, Alkalini ty,
Calcium X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-23 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source East Bend Scrubber Sludge Landfill, Cinergy (KY) FGD TDS, Iron, Sulfate U.S. EPA,

2007b Edgewater 1

- 4 Ash Disposal Site, Alliant (formerly Wisconsin Power & Light) (WI) Ash Boron, Sulfate, Iron,

Chlorides X X U.S. EPA,

2007b

Fayette Power Project (Sam Seymour), Lower Colorado River Authority (TX) Bottom Ash, Fly Ash, FGD, Other Selenium, Arsenic, Aluminum, Chlorides, Cobalt, Manganese, Molybdenum, Sulfate, TDS X X X EIP et al.,

2010b

Fern Valley Landfi ll, Orion Power Holdings, Inc. (a subsidiary of RRI Energy) (PA) Fly Ash Selenium, Aluminum, Boron, Chlorides, Lead, Sulfate, TDS X X X X EIP et al.,

2010a

Flint Creek Power Plant,

American Electric Power (AEP)/South West Electric Power Company (SWEPCO) ( AR) Bottom Ash, Fly Ash,

Other Selenium, Barium, Boron, Cadmium, Chromium, Iron, Lead, Manganese, pH, Silver, Sulfate, TDS X X X EIP et al.,

2010b

Fly Ash Landfill, Coffeen/ White & Brewer Trucking (IL) Not Specified Sulfate, TDS, Manganese X U.S. EPA,

2007b Fly Ash Landfill, Don Frame Trucking, Inc. (NY) Bottom Ash, Fly Ash,

Other Lead, Sulfate, TDS, Manganese X U.S. EPA,

2007b

General James M. Gavin Power Plant, American Electric Power/Ohio Power Company (OH) Bottom Ash, Fly Ash, FGD, Oth er Arsenic, Alpha Activity, Barium, Cadmium, Lead, Molybdenum, Sulfate, TDS, Aluminum, Copper, Nickel,

Zinc X X X EIP et al.,

2010b

George Neal Station North Landfill, Berkshire Hathaway/MidAmerican Energy Company (IA) Bottom Ash, Fly Ash Selenium, Iron , Manganese,

Sulfate X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-24 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source George Neal Station South Ash Monofill, Berkshire Hathaway/MidAmerican Energy Company (IA) Bottom Ash, Fly Ash Selenium, Arsenic, Barium, Zinc, Iron, Manganese,

Sulfate X X EIP et al.,

2010b

Gibson Gener ating Station, Duke Energy (IN) Bottom Ash, Fly Ash Selenium, Arsenic, Boron, Manganese, Iron X X X EIP et al.,

2010a Hatfield's Ferry Power Station, Allegheny Energy (PA) Bottom Ash, Fly Ash,

FGD Arsenic, Aluminum, Boron, Chromium, Iron, Manganese, Mol ybdenum, Thallium, TDS, Sulfate X X X EIP et al.,

2010b

Highway 59 Landfill, Wisconsin Electric Power Company (WEPCO) (WI) Bottom Ash, Fly Ash Selenium, Sulfate, Boron, Manganese, Chlorides, Iron X X U.S. EPA,

2007b

Independence Steam Station,

Ente rgy/Arkansas Power and Light (AR) Bottom Ash, Fly Ash,

Other Selenium, Cadmium, Iron, Lead, Manganese, pH, Sulfate, TDS, Strontium,

Boron X X EIP et al.,

2010b

Indian River Generating Station, NRG Energy (DE) Bottom Ash, Fly Ash Selenium, Mercury,

Ars enic, Aluminum, Antimony, Barium, Cadmium, Chromium, Copper, Lead, Nickel, Thallium, Vanadium, Zinc, Iron, Manganese X X X EIP et al.,

2010a

John Warden Ash Site (MI) Not Specified Boron , Lithium MDNRE,

2010 Johnsonville Fossil Plant,

Tennessee Va lley Authority (TVA) (TN) Bottom Ash, Fly Ash Arsenic, Aluminum, Boron, Cadmium, Chromium, Chlorides, TDS, Iron, Lead, Manganese, Molybdenum,

Sulfate X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-25 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source

K.R. Rezendes South Main Street Ash Landfill, Salem Harbor and Brayton Point Pl ants, Pacific Gas and Electric (PG&E) (MA) Ash Selenium, Sulfate, TDS, Manganese, Iron,

Aluminum X U.S. EPA,

2007b

Lincoln Stone Quarry Landfill, Joliet Generating Station 9, Midwest Generation (IL) Bottom Ash,

Other Arsenic, Ammonia, Boron,

Chlorid es, Fluoride, Manganese, Molybdenum, pH, Sodium, Sulfate, TDS, Barium, Copper, Nitrate X X X EIP et al.,

2010b

Mahoney Landfill,

Commonwealth Edison Powerton Plant (IL) Ash Cadmium, Lead, Nitrate, Iron, Manganese, Sulfate X U.S. EPA,

2007b

Marion Plant, Southern Illinois Power Cooperative (IL) Bottom Ash, Fly Ash,

FGD Boron, Cadmium, Iron, Aluminum, Manganese X X X X EIP et al.,

2010b

Miamiview Landfill, Cincinnati Gas & Electric Company (OH) Not Specified Sulfate X U.S. EPA,

2007b

Mill Cr eek Plant, E ON

U.S./Louisville Gas & Electric (LG&E) (KY) Bottom Ash, Fly Ash, FGD, Other Arsenic, Chlorides, Sodium, Sulfate, TDS X X EIP et al.,

2010b

Mitchell Power Station, Allegheny Energy (PA) Bottom Ash, Fly Ash Arsenic, Ammonia, Boron,

Calciu m, Chlorides, Iron, Molybdenum, Magnesium, Manganese, Nickel, Potassium, Sodium, Sulfate, Total Alkalinity, TDS X X X EIP et al.,

2010a

Morgantown Generating Station,

Faulkner Off

- Site Disposal Facility (MD) Bottom Ash, Fly Ash,

Other Iron, pH X X U .S. EPA,

2007b

Muscatine County Landfill (IA) Ash Selenium, Sulfate, pH, Iron X U.S. EPA,

2007bAppendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-26 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Muskegon County Type III Landfill (MI) Not Specified Boron, Manganese MDNRE,

2010 North Lansing Landfill, Lansing Board of Water & Light (MI) Ash, Other Selenium, Boron, Iron, Lithium, Manganese, pH Potassium, Strontium,

Sulfate U.S. EPA,

2007b

Northeastern Station Ash Landfill, American Electric Power/Public Service Company Oklahoma (OK) Bottom Ash, Fly Ash Selenium, Arsenic, Barium,

Chromi um, Lead, Vanadium, Thallium, Sulfate, pH X X X EIP et al.,

2010b

Oak Creek Power Plant, Wisconsin Energy (WE Energies (WE))/Wisconsin Electric Power Company (WI) Bottom Ash, Fly Ash, FGD, Other Mercury, Arsenic, Molybdenum, Manganese, Sulfate, Boron, F luoride X X EIP et al.,

2010b

Petersburg Generating Station, Indiana Power & Light (IN) Not Specified Sulfate, TDS X U.S. EPA,

2007b Phillips Power Plant Landfill, Duquesne Light Company (PA) Ash, FGD TDS, Chlorides, Sodium, Fluoride, Manganese

, Aluminum, Sulfate X X EIP et al.,

2010a

Pine Hill Landfill, Marquette Board of Light & Power (MI) Not Specified Boron , Lithium, Sodium MDNRE,

2010 Port Washington Facility,

Wisconsin Electric Power Company (WEPCO) (WI) Ash Selenium, Boron X U.S. U.S. EPA, 2007b

Presque Isle Power Plant, WE Energies (WE) (MI) Not Specified Boron , Lithium, Sodium MDNRE,

2010 Pulliam Ash Disposal Site, Wisconsin Power Supply Company (WPSC) (WI) Ash Sulfate, Manganese, Iron U.S. EPA,

2007b

R.M . Heskett Station, Montana

Dakota Utilities (ND) Ash Sulfate, Boron X U.S. EPA,

2007b R.M. Schahfer Generating Station (IN) Not Specified Sulfate X U.S. EPA,

2007bAppendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-27 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Range Road Landfill, Detroit Edison (MI) Ash Boron, Lithium, Sulfate,
Iron, Ma nganese MDNRE,

2010 Reid Gardner Generating Facility, Nevada Energy (NV) Fly Ash,

FGD Selenium, Arsenic, Chlorides, Sulfate, TDS, Nitrate, Boron, Chromium, Manganese, Magnesium, Molybdenum, Sodium, Vanadium, Titanium X X X EIP et al.,

2010a

Rock Ri ver Ash Disposal Facility, Alliant (formerly Wisconsin Power & Light) (WI) Ash Mercury, Arsenic, Sulfate,

Iron X U.S. EPA,

2007b

Rodemacher Power Station,

Central Louisiana Electric Co

Op (CLECO) Power, LLC (LA) Bottom Ash, Fly Ash,

Other Arsenic, L ead, pH, TDS, Specific Conductance, Chlorides, Sulfate X X X EIP et al.,

2010b

Seminole Generating Station, Seminole Electric Cooperative (FL) Fly Ash, FGD, Other Arsenic, Chlorides, Sulfate, Iron, TDS, Boron, Aluminum, Lead, Sodium X X X EIP et al.,

2010a

Seward Generating Station, RRI Energy (PA) Ash, Other Selenium, Arsenic, Aluminum, Antimony, Cadmium, Chlorides, Chromium, Iron, Lead, Manganese, Nickel, pH, Sulfate, TDS, Turbidity, Zinc, Sodium, Calcium, Barium, Boron, Fluoride, Magnesium X X X EIP et al.,

2010a

Shawnee Fossil Plant, Tennessee Valley Authority (TVA) (KY) Bottom Ash, Fly Ash Selenium, Arsenic, Boron, pH, Sulfate, TDS X X X EIP et al.,

2010b Spurlock Station, Eastern Kentucky Power Cooperative (KY) Bottom Ash, Fly Ash,

FGD Arse nic, Sulfate, Iron, TDS X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-5. Summary of Documented Gr ound Water Damage Cases

from LandfillsA-28 Case Study Site a Type of

Wastes

Present b Pollutants of Concern Exceeded

MCL c Exceeded

Federal/ State WQC/

Standards c Ground

Water Impacted

Surface

Waters d Impacted

Off- Site

Source e Source Swift Creek Structural Fill, ReUse Technology, Inc./Full Circle Solutions (NC) Fly Ash Mercury, Arsenic, Barium, Lead, Sulfate X X X EIP et al.,

2010a

Urquhart Station, South Carolina

Electric & Gas Com pany (SGE&E) (SC) Ash Arsenic, Nickel X EIP et al.,

2010a

Weber Ash Disposal Site, AES Creative Resources (NY) Ash Sulfate, TDS, Manganese, Iron, Aluminum, pH X U.S. EPA,

2007b Westland Disposal Site, Dickerson Generating Station, Mirant (MD) Fly Ash Selenium, Arsenic, Barium, Chromium, Cobalt, Copper, Iron, Zinc X Gazette,

2011

Yard 520 Landfill Site (Brown's Landfill), Northern Indiana Public Service Company (NIPSCO) (IN) Fly Ash,

Other Arsenic, Benzene, Manganese, Boron, Molybdenum, Lea d X U.S. EPA,

2007b

Yorktown Power Station, Chisman Creek Disposal Site, Virginia Electric Power and Power Company (VEPCO) (VA) Fly Ash Arsenic, Vanadium, Sulfate, Beryllium, Chromium, Copper, Molybdenum, Nickel, Vanadium X U.S. EPA,

2007b

Ac ronyms: FGD (Flue Gas Desulfurization); MCL (Maximum Contaminant Level); TDS (Total Dissolved Solids); WQC (Water Quality Cri teria).

a – This damage case listing is based on a subset of the damage cases that were reviewed by EPA [U.S. EPA, 2012b; U.S. EPA, 2013e].

b

– The term “ash” was used when the impact case study source did not identify the type of ash present at the waste management un it.

c – An “X” indicates that one or more of the pollutants listed exceeded MCLs or federal/state WQC/standards.

d – A n “X” indicates that the ground water contaminated the surface water with one or more of the pollutants listed.

e – An “X” indicates that the ground water contaminated a source outside the plant property boundaries.Appendix A

— Literature Review Methodology and Results



### Table A-6 . Summary of Documented Surface Water Damage Cases from Surface ImpoundmentsA-29 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal/ State WQC/

Standards c Issued a Fish Consumption

Advi sory d Impact Resulted

from Ground

Water

Contamination e Impacted

Off- Site

Source f Source Bangor Quarry Ash Disposal Site, Portland Generating Station, RRI Energy (PA) Bottom Ash, Fly Ash, Other Selenium, Arsenic, Barium, Boron, Cadmium, Hexavalent

Chrom ium, Potassium, pH, Iron, Manganese, Sulfate, TDS, Aluminum, Fluoride,

Chlorides X EIP et al.,

2010a

Belews Creek Steam Station, Duke Energy (NC) Fly Ash, FGD Selenium, Mercury, Arsenic, Barium, Boron, Cadmium, Copper, Chromium, Chlorides, Fluoride, Iron, Lead, Manganese, Nitrate, Silver, Zinc, Sulfate, TDS, TOH, TOC, pH X X X EIP et al.,

2010a

Big Bend Station, Tampa Electric Company (FL) Bottom Ash, Fly Ash, FGD,

Other Arsenic, Aluminum, Boron, Chlorides, Fluoride, Iron, Manganese, Molybdenum, S ulfate, Sodium, Thallium, Gross Alpha, TDS X X EIP et al.,

2010a

Bull Run Steam Plant, Tennessee Valley Authority (TVA) (TN) Ash, Other Aluminum, Cadmium, Iron, Sulfate U.S. U.S. EPA,

2007b Cardinal Fly Ash Reservoir (FAR) 1 and 2, American

E lectric Power (AEP) (OH) Bottom Ash, Fly Ash, FGD Arsenic, Boron, Molybdenum X X X EIP et al.,

2010b

Cayuga Coal Ash Disposal Landfill, AES (NY) Bottom Ash, Fly Ash, Other Selenium, Arsenic, Boron, Cadmium, Lead, TDS, Aluminum, Manganese, Sulfate X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-6 . Summary of Documented Surface Water Damage Cases from Surface ImpoundmentsA-30 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal/ State WQC/

Standards c Issued a Fish Consumption

Advi sory d Impact Resulted

from Ground

Water

Contamination e Impacted

Off- Site

Source f Source Clinch River Plant, American

Electric Power (AEP)/Appalachian Power (VA) Bottom Ash, Fly Ash Aluminum, pH X EIP et al.,

2010b

Columbia Energy Center, Alliant Energy (WI) Bottom Ash, Fly Ash Cadmium, Copper, Barium, Aluminum,

Iro n, Zinc X EIP et al.,

2010b

Curtis Stanton Energy Center, Orlando Utility Commission (FL) Bottom Ash, Fly Ash, FGD,

Other Aluminum, Beryllium, Calcium, Chlorides, Iron, Manganese, Sodium, Sulfate, TDS, Vanadium, Gross Alpha,

Radium

- 226, pH X E IP et al.,

2010a

Fayette Power Project (Sam Seymour), Lower Colorado River Authority (TX) Bottom Ash, Fly Ash, FGD,

Other Selenium, Arsenic, Aluminum, Chlorides, Cobalt, Manganese, Molybdenum, Sulfate,

TDS X X EIP et al.,

2010b

Gallatin Fossil Plant, Tennessee Valley Authority (TVA) (TN) Bottom Ash, Fly Ash Aluminum, Boron, Beryllium, Cadmium, Iron, Manganese, Nickel, Sulfate, TDS X X X EIP et al.,

2010b

General James M. Gavin Power Plant, American

Electric Power/Ohio Power Company (OH) Bottom Ash, Fly Ash, FGD,

Other Arsenic, Alpha Activity, Barium, Cadmium, Lead, Molybdenum, Sulfate, TDS, Aluminum, Copper, Nickel, Zinc X X EIP et al.,

2010b

Gibson Generating Station, Duke Energy (IN) Bottom Ash, Fly Ash Selenium, Arsenic, Boron, Manganese, Ir on X X EIP et al.,

2010a Glen Lyn Plant, American

Electric Power (AEP)/Appalachian Power (VA) Bottom Ash, Fly Ash Selenium, Cadmium, Copper, Chromium, Zinc, pH, TSS X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-6 . Summary of Documented Surface Water Damage Cases from Surface ImpoundmentsA-31 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal/ State WQC/

Standards c Issued a Fish Consumption

Advi sory d Impact Resulted

from Ground

Water

Contamination e Impacted

Off- Site

Source f Source Hunlock Power Station, UGI Development Company (PA) Ash Arsenic , Iron, Manganese, Barium, Boron, Lithium X X X EIP et al.,

2010a

J.H. Campbell, Consumers Energy (MI) Not Specified Selenium, Boron, Lithium, Antimony MDNRE,

2010 J.R. Whiting Generating Plant, CMS/Consumers Energy (MI) Fly Ash, Other Selenium, Ar senic, Cobalt, Possibly Nickel X EIP et al.,

2010b John Sevier Fossil Plant, Tennessee Valley Authority (TVA) (TN) Bottom Ash, Fly Ash Arsenic, Aluminum, Cadmium, Manganese, Boron, Strontium,

Sulfate X X X EIP et al.,

2010a

Johnsonville Fossil Pl ant, Tennessee Valley Authority (TVA) (TN) Bottom Ash, Fly Ash Arsenic, Aluminum, Boron, Cadmium, Chromium, Chlorides, TDS, Iron, Lead, Manganese, Molybdenum, Sulfate X EIP et al.,

2010b

Karn/Weadock Generating Facility, Consumer Energy (MI) Ash Mer cury, Arsenic, Boron, Lithium, Phosphorus X EIP et al.,

2010a

Kingston Fossil Plant, Tennessee Valley Authority (TVA) (TN) Fly Ash Arsenic, Selenium, Barium, Cadmium, Lead X X X AECOM, 2009; ASU,

2009

Little Blue Run Surface Impoundment, Bruce

Ma nsfield Power Plant, First Energy (PA) Bottom Ash, Fly Ash, FGD Selenium, Arsenic, Aluminum, Antimony, Barium, Boron, Cadmium, Calcium, Chlorides, Hexavalent Chromium, Fluoride, Iron, Lead, Manganese, pH, Sodium, Sulfate, TDS, TSS, Thallium, Turbidity X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-6 . Summary of Documented Surface Water Damage Cases from Surface ImpoundmentsA-32 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal/ State WQC/

Standards c Issued a Fish Consumption

Advi sory d Impact Resulted

from Ground

Water

Contamination e Impacted

Off- Site

Source f Source Little Scary Creek Fly Ash Impoundment, John Amos Plant, American Electric Power (AEP)/Appalachian Power (WV) Bottom Ash, Fly Ash Selenium X X X EIP et al.,

2010a

Marion Plant, Southern Illinois Power Cooperative (IL) Bottom Ash, Fly Ash, FGD Boron, Cadmium, Iron, Aluminum, Manganese X X X EIP et al.,

2010b

Martin's Creek Power Plant, PPL (PA) Fly Ash Arsenic, Selenium, Mercury, Lead, Aluminum, Manganese, Copper X X DRBC,

2006

Mitchell Power Station, Allegheny Energy (PA) Bot tom Ash, Fly Ash Arsenic, Ammonia, Boron, Calcium, Chlorides, Iron, Molybdenum, Magnesium, Manganese, Nickel, Potassium, Sodium, Sulfate, Total Alkalinity, TDS X X EIP et al.,

2010a

Morgantown Generating Station, Faulkner Off

- Site Disposal Facility (M D) Bottom Ash, Fly Ash, Other Iron, pH X X U.S. U.S. EPA,

2007b Muskingum River Plant,

American Electric Power (AEP)/ Ohio Power Company (OH) Bottom Ash, Fly Ash Arsenic, Barium, Iron,

Sulfate X X EIP et al.,

2010b

Oak Ridge Y

- 12 Plant,

Chestnut Ridge Operable Unit 2, Oak Ridge Reservation, Department of Energy (TN) Bottom Ash, Fly Ash Selenium, Arsenic, Lead, Aluminum, Iron, Barium, Cobalt, Magnesium, Zinc, Copper, Calcium, Manganese, Potassium, Thallium, Sodium X U.S. U.S. EPA,

2007bAppendix A

— Literature Review Methodology and Results



### Table A-6 . Summary of Documented Surface Water Damage Cases from Surface ImpoundmentsA-33 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal/ State WQC/

Standards c Issued a Fish Consumption

Advi sory d Impact Resulted

from Ground

Water

Contamination e Impacted

Off- Site

Source f Source

Pla nt Bowen, Georgia Power (GA) Bottom Ash, Fly Ash, Other Not Specified U.S. U.S. EPA,

2007b Rodemacher Power Station,

Central Louisiana Electric Co

Op (CLECO) Power, LLC (LA) Bottom Ash, Fly Ash, Other Arsenic, Lead, pH, TDS, Specific Conductance, Chlorides, Sulfate X X EIP et al.,

2010b

Savannah River Site, D

- Area, Department of Energy (SC) Fly Ash Not Specified U.S. EPA,

2007b Seminole Generating Station, Seminole Electric Cooperative (FL) Fly Ash, FGD,

Other Arsenic, Chlorides, Sulfate, Iron, TDS, Boron, Aluminum, Lead,

Sodium X X EIP et al.,

2010a

Seward Generating Station, RRI Energy (PA) Ash, Other Selenium, Arsenic, Aluminum, Antimony, Cadmium, Chlorides, Chromium, Iron, Lead, Manganese, Nickel, pH, Sulfate, TDS, Turbidity,

Zinc , Sodium, Calcium, Barium, Boron, Fluoride, Magnesium X X EIP et al.,

2010a

Shawnee Fossil Plant, Tennessee Valley Authority (TVA) (KY) Bottom Ash, Fly Ash Selenium, Arsenic, Boron, pH, Sulfate, TDS X X EIP et al.,

2010b

Sherburne County (Sherco) Generating Plant, Xcel Energy/Southern Minnesota Municipal Power Agency (MN) Bottom Ash, Fly Ash, FGD Arsenic, Cadmium, Chromium, Fluoride, Lead, Nitrate, Chlorides, Copper, Iron, Manganese, Sulfate,

Zinc X U.S. U.S. EPA,

2007bAppendix A

— Literature Review Methodology and Results



### Table A-6 . Summary of Documented Surface Water Damage Cases from Surface ImpoundmentsA-34 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal/ State WQC/

Standards c Issued a Fish Consumption

Advi sory d Impact Resulted

from Ground

Water

Contamination e Impacted

Off- Site

Source f Source

W.J. Neal Station Su rface Impoundment, Basin Electric Power Cooperative (ND) Fly Ash, FGD,

Other Selenium, Arsenic, Antimony, Chromium, Manganese, Sodium, Cadmium, Lead, Zinc X U.S. U.S. EPA,

2007b

Westland Disposal Site, Dickerson Generating Station, Mirant (MD) Fly A sh Selenium, Arsenic, Barium, Chromium, Cobalt, Copper, Iron,

Zinc X Gazette,

2011

Acronyms: FGD (Flue Gas Desulfurization); TDS (Total Dissolved Solids); TOC (Total Organic Carbon); TOH (Total Organic Hydroc arbons); TSS (Total Suspended Solids); WQC ( Water Quality Criteria).

a – This damage case listing is based on a subset of the damage cases that were reviewed by EPA [U.S. EPA, 2012b; U.S. EPA, 2013e ].

b

– The term “ash” was used when the impact case study source did not identify the type of ash present at the waste management unit.

c – An “X” indicates that one or more of the pollutants listed exceeded federal/state WQC/standards.

d – An “X” indicates that the contaminated surface water was issued a fish consumption advisory.

e – An “X” indicates that the ground water contaminated the surface water with one or more of the pollutants listed.

f

– An “X” indicates that the surface water contaminated a source outside the plant property boundaries.Appendix A

— Literature Review Methodology and Results



### Table A-7 . Summary of Documented Surface Water Damage Cases

from LandfillsA-35 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal / State WQC/

Standards c Issued a Fish Consumption

Advisory d Impact

Resulted from

G round Water

Contamination e Impacted

Off-S ite

Source f Source Bangor Quarry Ash Disposal Site, Portland Generating Station, RRI Energy (PA) Bottom Ash, Fly Ash, Other Selenium, Arsenic, Barium, Boron, Cadmium, Hexavalent Chromium, Potassium, pH, Iron, Man ganese, Sulfate, TDS, Aluminum, Fluoride,

Chlorides X EIP et al.,

2010a

Belews Creek Steam Station, Duke Energy (NC) Fly Ash, FGD Selenium, Mercury, Arsenic, Barium, Boron, Cadmium, Copper, Chromium, Chlorides, Fluoride, Iron, Lead, Manganese, Nitra te, Silver, Zinc, Sulfate, TDS, TOH, TOC, pH X X X EIP et al.,

2010a

Big Bend Station, Tampa Electric Company (FL) Bottom Ash, Fly Ash, FGD,

Other Arsenic, Aluminum, Boron, Chlorides, Fluoride, Iron, Manganese, Molybdenum, Sulfate, Sodium, Thallium, Gro ss Alpha, TDS X X EIP et al.,

2010a

Brandywine Coal Ash Landfill,

Mirant Mid

- Atlantic (LLC) Bottom Ash, Fly Ash Selenium, Cadmium, Lead, Manganese, Iron, Aluminum, Sulfate, TDS, Chlorides X X EIP et al.,

2010a

Cardinal Fly Ash Reservoir (FAR) 1 a nd 2, American Electric Power (AEP) (OH) Bottom Ash, Fly Ash, FGD Arsenic, Boron, Molybdenum X X X EIP et al.,

2010b

Cayuga Coal Ash Disposal Landfill, AES (NY) Bottom Ash, Fly Ash, Other Selenium, Arsenic, Boron, Cadmium, Lead, TDS, Aluminum, Manganese , Sulfate X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-7 . Summary of Documented Surface Water Damage Cases

from LandfillsA-36 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal / State WQC/

Standards c Issued a Fish Consumption

Advisory d Impact

Resulted from

G round Water

Contamination e Impacted

Off-S ite

Source f Source CCW Landfill, Trans

- Ash, Inc. (TN) Bottom Ash, Fly Ash Mercury, Iron, Boron,

Sulfate X EIP et al.,

2010a Columbia Energy Center, Alliant Energy (WI) Bottom Ash, Fly Ash Cadmium, Copper, Barium, Aluminum, Iron, Zi nc X EIP et al.,

2010b

Curtis Stanton Energy Center, Orlando Utility Commission (FL) Bottom Ash, Fly Ash, FGD,

Other Aluminum, Beryllium, Calcium, Chlorides, Iron, Manganese, Sodium, Sulfate, TDS, Vanadium, Gross Alpha,

Radium

- 226, pH X EIP et al.,

2010a

Fayette Power Project (Sam Seymour), Lower Colorado River Authority (TX) Bottom Ash, Fly Ash, FGD,

Other Selenium, Arsenic, Aluminum, Chlorides, Cobalt, Manganese, Molybdenum, Sulfate,

TDS X X EIP et al.,

2010b

Fern Valley Landfill, Orion Power Holdings, Inc. (a subsidiary of RRI Energy) (PA) Fly Ash Selenium, Aluminum, Boron, Chlorides, Lead, Sulfate, TDS X X X EIP et al.,

2010a

General James M. Gavin Power Plant, American

Electric Power/Ohio Power Company (OH) Bottom Ash, Fly Ash, FG D,

Other Arsenic, Alpha Activity, Barium, Cadmium, Lead, Molybdenum, Sulfate, TDS, Aluminum, Copper, Nickel, Zinc X X EIP et al.,

2010b

Gibson Generating Station, Duke Energy (IN) Bottom Ash, Fly Ash Selenium, Arsenic, Boron, Manganese, Iron X X EIP et al.,

2010a Hatfield's Ferry Power Station, Allegheny Energy (PA) Bottom Ash, Fly Ash, FGD Arsenic, Aluminum, Boron, Chromium, Iron, Manganese, Molybdenum, Thallium, TDS, Sulfate X X EIP et al.,

2010bAppendix A

— Literature Review Methodology and Results



### Table A-7 . Summary of Documented Surface Water Damage Cases

from LandfillsA-37 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal / State WQC/

Standards c Issued a Fish Consumption

Advisory d Impact

Resulted from

G round Water

Contamination e Impacted

Off-S ite

Source f Source Indian River Generating Station, NRG Energy (D E) Bottom Ash, Fly Ash Selenium, Mercury, Arsenic, Aluminum, Antimony, Barium, Cadmium, Chromium, Copper, Lead, Nickel, Thallium, Vanadium, Zinc, Iron, Manganese X X EIP et al.,

2010a

John Warden Ash Site (MI) Not Specified Boron , Lithium MDNRE,

2010 Johnsonville Fossil Plant, Tennessee Valley Authority (TVA) (TN) Bottom Ash, Fly Ash Arsenic, Aluminum, Boron, Cadmium, Chromium, Chlorides, TDS, Iron, Lead, Manganese, Molybdenum, Sulfate X EIP et al.,

2010b

Little Scary Creek Fly Ash Impound ment, John Amos Plant, American Electric Power (AEP)/Appalachian Power (WV) Bottom Ash, Fly Ash Selenium X X X EIP et al.,

2010a

Mahoney Landfill,

Commonwealth Edison Powerton Plant (IL) Ash Cadmium, Lead, Nitrate, Iron, Manganese, Sulfate U.S. U.S. EPA,

2007b Marion Plant, Southern Illinois Power Cooperative (IL) Bottom Ash, Fly Ash, FGD Boron, Cadmium, Iron, Aluminum, Manganese X X X EIP et al.,

2010b Mitchell Power Station, Allegheny Energy (PA) Bottom Ash, Fly Ash Arsenic, Ammonia,

Boron , Calcium, COD, Chlorides, Iron, Molybdenum, Magnesium, Manganese, Nickel, Potassium, Sodium, Sulfate, Total Alkalinity, TDS X X EIP et al.,

2010aAppendix A

— Literature Review Methodology and Results



### Table A-7 . Summary of Documented Surface Water Damage Cases

from LandfillsA-38 Case Study Site a Type of Wastes

Present b Pollutants of Concern Exceeded

Federal / State WQC/

Standards c Issued a Fish Consumption

Advisory d Impact

Resulted from

G round Water

Contamination e Impacted

Off-S ite

Source f Source Morgantown Generating Station, Faulkner Off

- Site Disposal Facility (MD) Bottom Ash, Fly Ash, Other Iron, pH X X U.S. EPA,

2007b

Northeastern Station Ash Landfill, American Electric

Power/Public Service Company Oklahoma (OK) Bottom Ash, Fly Ash Selenium, Arsenic, Barium, Chromium, Lead, Vanadium, Thallium, Sulfate, pH X X EIP et al.,

2010b

Range Roa d Landfill, Detroit Edison (MI) Ash Boron, Lithium, Sulfate, Iron, Manganese MDNRE,

2010 Rodemacher Power Station,

Central Louisiana Electric Co

Op (CLECO) Power, LLC (LA) Bottom Ash, Fly Ash, Other Arsenic, Lead, pH, TDS, Specific Conductance,

Chlori des, Sulfate X X EIP et al.,

2010b

Seminole Generating Station, Seminole Electric Cooperative (FL) Fly Ash, FGD,

Other Arsenic, Chlorides, Sulfate, Iron, TDS, Boron, Aluminum, Lead,

Sodium X X EIP et al.,

2010a

Seward Generating Station,

RRI Ener gy (PA) Ash, Other Selenium, Arsenic, Aluminum, Antimony, Cadmium, Chlorides, Chromium, Iron, Lead, Manganese, Nickel, pH, Sulfate, TDS, Turbidity, Zinc, Sodium, Calcium, Barium, Boron, Fluoride, Magnesium X X EIP et al.,

2010a

Shawnee Fossil Plant,

T ennessee Valley Authority (TVA) (KY) Bottom Ash, Fly Ash Selenium, Arsenic, Boron, pH, Sulfate, TDS X X EIP et al.,

2010b

Westland Disposal Site, Dickerson Generating Station, Mirant (MD) Fly Ash Selenium, Arsenic, Barium, Chromium, Cobalt, Copper, Ir on, Zinc X Gazette,

2011Appendix A

— Literature Review Methodology and Results

Acronyms: COD (Chemical Oxygen Demand); FGD (Flue Gas Desulfurization); TDS (Total Dissolved Solids); TOC (Total Organic Carb on); TOH (Total Organic Hydrocarbons); TSS (Total Suspended Solids); WQC (Water Quality Criteria).

a – This damage case listing is based on a subset of the damage cases that were reviewed by EPA [U.S. EPA, 2012b; U.S. EPA, 2013e ].

b – The term “ash” was used when the impact case study source did not identify the type of ash present at the waste management unit.

c – An “X” indicates that one or more of the pollutants listed exceeded federal/state WQC/standards.

d – An “X” indicates that the contaminated surface water was issued a fish consumption advisory.

e – An “X” indicates that the ground water contamina ted the surface water with one or more of the pollutants listed.

f

– An “X” indicates that the surface water contaminated a source outside the plant property boundaries.A-39Appendix A

— Literature Review Methodology and Results



### Table A-8. Summ ary of Attractive Nuisance Case Studies Related to Steam Electric Power PlantsA-40 Species Attractive Nuisance Site Description Metals Concentrations in

the Environment or Diet Metals Concentrations in the Organism ( μg/g) Observed Effects Study Type Citation

Common grackles ( Quiscalus quiscala ) Nested in close proximity to a coal

fired power plant’s fly ash pond • Not measured in study • Eggs = 5.9 selenium • Histopathological Field Bryan et al.,

2003

Raccoons ( Procyon lotor ) Lived in close proximity to a coal

f ired power plant’s ash pond • Not measured in study • Heart = 2.8 arsenic

• Kidney = 3.2 cadmium,

0.43 strontium

• Muscle = 0.95 chromium

• Liver = 0.34 lead, 1.5

mercury • Histopathological Field Burger et al.,

2002

Interior least tern ( Sterna antillarum ) Nested on a dike in a

coal

- fired power plant’s ash pond • Not measured in study • Not observed in study • Not observed in study Field Pruitt, 2000

and Duke Energy, 2007

Southern toads (Bufo terrestris ) Inhabited an ash basin and nearby swamp

Reference (control) site

org anisms were

transferred to

contaminated locations • Not measured in study • Not measured in study • Elevated

corticosterone and

testosterone levels Outdoor

mesocosm Hopkins et al.,

1997

Southern toads (Bufo terrestris ) Inhabited an ash pond and nearby swamp

Re ference site organisms were

transferred to

contaminated locations • Pond sediment = 39.64 μg/g arsenic, 4.38 μg/g

selenium • Adult males = 1.58 arsenic, 17.40 selenium • Histopathological Outdoor

mesocosm Hopkins et al.,

1998

Larval bullfrogs (Rana catesbeiana ) Inhabited bottom ash ponds near a coal

- fired power plant • Pond sediment = 49.39 μg/g arsenic, 0.72 μg/g cadmium, 23.85 μg/g chromium, 84.72 μg/g copper, 6.11 μg/g selenium, 106.39 μg/g strontium, 45.83 μg/g

vanadium • Whole body

concentration = 33.10

arsenic , 5.47 cadmium, 18.25 chromium, 116.72 copper, 20.25 selenium, 39.89 strontium, 17.32

vanadium • Morphological

• Decreased swimming speeds Field Hopkins et al.,

2000Appendix A

— Literature Review Methodology and Results



### Table A-8. Summ ary of Attractive Nuisance Case Studies Related to Steam Electric Power PlantsA-41 Species Attractive Nuisance Site Description Metals Concentrations in

the Environment or Diet Metals Concentrations in the Organism ( μg/g) Observed Effects Study Type Citation

Eastern narrow

mouth toads ( Gastrophryne carolinensis) Inhabited a selenium

laden site locate d near a

coal

- fired power plant • Site water = 3.93 μg/L

selenium

• Soil = 38.25 μg/L

selenium

• Lab water = 0.28 μg/L

selenium • Females = 42.40

selenium

• Eggs = 43.96 selenium • Reproductive

• Histopathological Outdoor

mescosm Hopkins et al.,

2006

Barn swallow ( Hir undo rustica ) Nested near a selenium

laden pond associated

with a coal

- fired power plant • Not provided in the

literature • Eggs = 2.8 selenium • Histopathological Field King et al.,

1994

Slider turtles ( Trachemys scripta ) Inhabited a selenium

laden basin that receives sluiced fly ash

near a coal

- fired power plant

Eggs were incubated in

ash

- contaminated soil • Ash

- contaminated soil = 2.56 μg/g selenium • Adult Females = 37.18 (mean concentration),

selenium • Reproductive Outdoor

mescosm Nagle et al.,

2001

Canada geese (Branta

Canadensis ) Inhabited pens near a

vanadium

- laden ash pond associated with an

oil

- fired power plant • Site water = 467,000 μg/L vanadium • Liver = 57.3 vanadium

• Kidney = 226 vanadium • Lethal

• Histopathological Outdoor

mesocosm Rattner et al.,

2006

Acronyms: μg/g (Micrograms per Grams); μg/L (Micrograms per Liters).Appendix A

— Literature Review Methodology and Results



### Table A-9. Summary of Attractive Nuisance Case Studies Unrelated to Steam Electric Power PlantsA-42 Site Name, Locati on, and Contamination

Source Organism Affected Documented Effects Trace Metal Concentrations (ppm) Citation

Kesterson Reservoir, CA

Agricultural runoff California vole ( Microtus californicus ) Mean selenium concentrations in livers were significantly elev ated. • Liver = 119 selenium Clark et al., 1987

Kesterson Reservoir, CA

Agricultural runoff American coot ( Fulica americana ), mallard ( Anas platyrhynchos ) Mean selenium concentrations in bird eggs and livers were elevated; organisms exhibited severe reprod uctive failure and deformities. • Eggs = 2.2

– 110 selenium

• Liver = 19

– 130 selenium

• Water = 300,000 selenium Ohlendorf et al.,

1986

Kesterson Reservoir, CA

Agricultural runoff Pied

- billed grebes ( Podilymbus podiceps ), common moorhen ( Gallinula chloropus ) , black

necked stilts ( Himantopus

mexicanus ) Selenium concentrations in livers were 10 times those found in nearby control areas; organisms exhibited severe lesions and embryonic

deformities. • Liver = 94.4 selenium

• Water = 300,000 selenium Ohlendorf et al.,

1988a

Kesterson Reservoir, CA

Agricultural runoff Gopher snakes ( Pituophis

melanoleucus ), bullfrogs (Rana

catesbeiana ) Selenium concentrations in snake and frog livers were significantly

elevated. • Snake liver = 11.1 selenium

• Frog liver = 45.0 selenium O hlendorf et al.,

1988b

Kesterson Reservoir, CA

Agricultural runoff Eared grebe ( podiceps nigricollis ), mallard ( Anas platyrhynchos ), cinnamon teal ( Anas cyanoptera ), gadwall ( Anas strepera ), American coot ( Fulica americana ), killdeer ( Charadrius vocifero us ), black

necked stilt ( Himantopus

mexicanus ), American avocet ( Recurvirostra americana) Hatchlings exhibited mortality, deformity, and lack of embr yonic development. • Water = 300 selenium Ohlendorf et al.,

1989

Kesterson Reservoir, CA

Agricultural runof f Mosquitofish ( Gambusia affinis ), American coot ( Fulica americana) , ducks ( Anas spp .) Selenium concentrations in livers, kidneys, and muscles were elevated; organisms exhibited reduced body weight. • Fish = 120

– 140 selenium

• Coot liver = 76.7 selenium

• Duck liver = 25.2 selenium Ohlendorf et al.,

1990

Liberty State Park, NJ

Industrial and urban

activities House wren ( troglodytes aedon ), American robin ( Turdus migratorus ) Lead, arsenic, chromium, copper,

and iron concentrations in bird

feathers were elevate d. • Feather = 4,200 lead; 1,000 chromium; 6,200 copper; 600

arsenic Hofer et al., 2010Appendix A

— Literature Review Methodology and Results



### Table A-9. Summary of Attractive Nuisance Case Studies Unrelated to Steam Electric Power Plants

Site Name, Locati on, and Contamination

Source Organism Affected Documented Effects Trace Metal Concentrations (ppm) Citation

Meadowlands, NJ

Industrial and urban

activities Red

- winged blackbird ( agelaius phoeniceus ), marsh wrens ( Cistothorus palustris ), tree swallow ( Tachycineta bicolor ) Lea d and chromium concentrations in blood were elevated; mercury and chromium concentrations in eggs

were elevated. • Swallow blood = 0.94 lead; 1.03

chromium

• Wren eggs = 0.2 mercury

• Blackbird eggs = 0.12 chromium Tsipoura et al., 2008

Acronym: ppm (parts per million).A-43Appendix A

— Literature Review Methodology and Results



### Table A-10. Summary of Selenium Concentrations in the Environment and Organisms Experiencing Adverse EffectsA-44 Species Route of Selenium Exposure Selenium

Concentrations in the Environment ( μg/L) or Diet ( μg/g) Selenium Concentrations in the Organism ( μg/g) Observed Effects Study Type (Surface Water Type) Citation

Largemouth bass ( Micropterus

salmoides ) Inhabited a

selenium

- laden cooling water reservoir receiving ash pond e ffluent

from a coal

- fired power plant Not provided in the

literature Carcass = 2.86 (mean, female), 2.63 (mean, male) Gonad = 4.40 (mean, female), 2.38 (mean, male) Reproductive Histopathological Field (reservoir) Baumann and Gillespie, 1986

Bluegill ( Lep omis
macrochirus ) Carcass = 2.74 (mean, female), 4.64 (mean, male) Gonad = 4.63 (mean, female), 3.35 (mean, male)

Striped bass Consumed a Red Shiners = 9.6 μg/g Skeletal muscle = 3.8 Modified behavior Laboratory Coughlan and ( Morone saxatilis ) selenium

- laden diet (average whole

- body (higher average Decreased growth (reservoir) Velte, 1989 by eating red shiners concentration), wet concentration), wet Histopathological

collected from a site Lethal receiving coal ash pond sluic e water
Bluegill Inhabited a Not provided in the Not provided in the Lethal Field (reservoir) a Crutchfield and ( Lepomis selenium

- laden literature literature Ferguson, 2000a

macrochirus ) reservoir receiving coal ash pond

effluent

Green sunfish b Inhabited a Site water c = 7

– 14 Biomass d = 2,744

– 3,793 Lethal Field (reservoir) Crutchfield, ( Lepomis cyanellus) se lenium

- laden μg/L (mean) Reproductive 2000b reservoir receiving coal ash pond

effluent

Largemouth bass ( Micropterus

salmoides ) e Pomoxis spp

. Inhabited a

selenium

- laden cooling water reservoir receiving both fly ash and bottom ash pond

effluent from a coal

fired power plant Site water h = 10 μg/L Biomass i = 0.1

– 1.0 (mean) Lethal Reproductive Field (reservoir) Cumbie and Van Horn, 1978

Lepomis spp. f Body = 41.0

– 7 7.1 (54.6 mean concentration), wet

Lealurus spp. g Body = 0.31

– 15.5 (6.32 mean concentration), wetAppendix A

— Literature Review Methodology and Results



### Table A-10. Summary of Selenium Concentrations in the Environment and Organisms Experiencing Adverse EffectsA-45 Species Route of Selenium Exposure Selenium

Concentrations in the Environment ( μg/L) or Diet ( μg/g) Selenium Concentrations in the Organism ( μg/g) Observed Effects Study Type (Surface Water Type) Citation

Bluegill ( Lepomis

macrochirus ) Inhabited a

selenium

- laden cooling water

reservoir of a coal

fired power plant Site water j = 9

– 12 μg/L Testes = 4.37 (mean concentration) Ovaries = 6.96 (mean concentration) Reproductive Laboratory (reservoir) Gillepsie et al.,

1986

Banded water

snakes ( Nerodia fasciata ) Consumed a

selenium

- laden diet by eating prey

collected from a

contaminated site

located near a coal

fired power plant Prey items k = 22.7 μg/g (geometric least squared mean), dry Gonads = 17.64 (female), 19.06 (male) Kidney = 25.38 (female), 32.04 (male) Liver = 24.08 (female), 24.22 (male) Reproductive Histopathological Laboratory (not specified) Hopkins et al.,

2002

Eastern narrow

mouth toads ( Gastrophryne carolinensis) Inhabited a

selenium

- laden site

located near a coal

fired power plant Site water = 3.93 μg/L Soil = 8.25 μg/L Lab water = 0.28 μg/L Females = 42.40 Eggs = 43.96 Reproductive

Hist opathological Outdoor mescosm (combustion residuals pond) Hopkins et al.,

2006

Largemouth bass l
( Micropterus salmoides) Inhabited a

selenium

- laden cooling water reservoir receiving

effluent from the coal ash pond Ash effluent = 100

- 200 μg/L

Site water = 10 μg/L Visceral tissue = 40+ (highest mean concentration) Lethal Field (reservoir) Lemly, 1985a

Slider turtles ( Trachemys scripta ) Inhabited a

selenium

- laden pond receiving sluiced fly

ash near a coal

- fired power plant

Eggs were incubated

in ash

- contam inated

soil Ash

- contaminated soil = 2.56 μg/g, dry Adult females = 37.18 (mean concentration), dry Reproductive Outdoor mescosm (combustion residuals pond) Nagle et al.,

2001Appendix A

— Literature Review Methodology and Results



### Table A-10. Summary of Selenium Concentrations in the Environment and Organisms Experiencing Adverse EffectsA-46 Species Route of Selenium Exposure Selenium

Concentrations in the Environment ( μg/L) or Diet ( μg/g) Selenium Concentrations in the Organism ( μg/g) Observed Effects Study Type (Surface Water Type) Citation

Bluegill m ( Lepomis

macrochirus ) Inhabited a

selenium

- laden cooling water

reserv oir of a coal

fired power plant Site water = <10

– 20 μg/L Liver = 34 (mean concentration), wet Gonad = 12.1 (mean, female), 5.4 (mean, male),

wet Muscle = 13 (mean concentration), wet Histopathological Field (reservoir) Sager and Colfield, 1984

Largemouth bass n Liver = 10.2 (mean ( Micropterus concentration), wet

salmoides ) Gonad = 10.3 (mean, female), wet Muscle = 6.7 (mean concentration), wet

Green sunfish ( Lepomis cyanellus ) Inhabited a

selenium

- laden lake receiving coal fly ash, scrubber sludge,

a

nd coal bottom ash Not provided in the

literature Hepatopancreas = 1.31

– 9.30, wet Histopathological Field (lake) Sorensen et al.,

1982

Redear sunfish ( Lepomis microlophus ) Hepatopancreas = 2.8

– 11.03, wet

Redear sunfish Inha bited a Not provided in the Liver = 20 Histopathological Field Sorensen et al., ( Lepomis selenium

- laden lake literature (lake) 1983 microlophus ) receiving coal fly ash, scrubber sludge,

and coal bottom ash

Redear sunfish Inhabited a Not provided in the Hepatopancreas = 8.4

– 27.2 Increased weight loss Field Sorensen and ( Lepomis selenium

- laden lake literature μg/L (lake) Bauer, 1984a microlophus ) re ceiving coal ash pond wastewater Kidney = 11.4

– 115.7 μg/L

Ovaries = 0

– 5.9 μg/L

Testes = 0

– 54.2 μg/L

Green sunfish Inhabited a Site water = 13 μg/L Liver = 21.4, wet Histopathological Field Sorensen et al., ( Lepomis c yanellus ) selenium

- laden lake Sediment = 5

– 14 Skeletal muscle = 12.9, wet Hematological (lake) 1984b receiving coal fly

ash sluice water μg/g, dry Hematocrit = 33, wetAppendix A

— Literature Review Methodology and Results



### Table A-10. Summary of Selenium Concentrations in the Environment and Organisms Experiencing Adverse EffectsA-47 Species Route of Selenium Exposure Selenium

Concentrations in the Environment ( μg/L) or Diet ( μg/g) Selenium Concentrations in the Organism ( μg/g) Observed Effects Study Type (Surface Water Type) Citation

Redear sunfish ( Lepomis microlophus ) Inhabited a

selenium

- laden lake

located near a coal

fired power plant Not provided in the

literature Liver = 7.63 (mean concentration) Histopathological Reproductive Field (lake) Sorensen, 1988

Acronyms: kg/ha ( kilogram per hectacre); μg/L (micrograms per liter); μg/g (micrograms per gram).

a – The data used in this study were census data collected from routine biological monitoring undertaken by the facility.

b

– Multiple fish species were studied; however, the green sunfish had the highest documented selenium biomass concentrations.

c – These are the selenium water concentrations detected prior to the conversion to a dry fly ash handling system.

d – This concentration is measured in the units kg/ha. The range of selenium concentrations was reported annually from 1982 to 1989, before the power plant converted to dry ash handling.

e – Multiple fish species were studied; however, the largemouth bass and pomoxis spp. had the lowest documented selenium biomass concent rations.

f

– Multiple fish species were studied; however, the Lepomis spp. had the highest documented selenium skeletal muscle concentrations.

g – Multiple fish species were studied; however, the Letalurus spp. had the lowest documented selenium body conce ntrations.

h – This selenium concentration is dissolved.

i

– This concentration is measured in the units kg/ha. The range of selenium concentrations was reported annually from 1982 to 19 89, before the power plant converted to dry ash handling. Both fish sp ecies had the same range of selenium concentrations.

j

– This concentration was not measured for this study but was reported in a previous study conducted at the same site.

k – The banded water snakes were fed weekly combinations of previously frozen prey items inhabiting the coal ash

- contaminated site.

l

– The study documented only selenium concentrations for the largemouth bass.

m – Multiple fish species were studied; however, the bluegills had the highest documented selenium liver tissue concentration.

n – Multiple fish species were studied; however, the largemouth bass had the lowest documented selenium liver tissue concentratio n.Appendix B

— Proximity Analyses Supporting Tables



# APPENDIX B

PROXIMITY ANALYSES S UPPORTING TABLES

Table B-1. I mmediate Receiving Waters 303(d) Impairments Listing

Cause Group Name Cause Name Found in

Combustion

Wastewater Evaluated in

the EA
Algal Growth Algal Growth

Algal Growth Chlorophyll -A

Ammonia Ammonia  

Ammonia Ammonia, Un -Ionized  

Ammonia Total Ammonia  

Cause Unknown Cause Unknown

Cause Unknown

- Impaired Biota Benthic Macroinvertebrates

Cause Unknown

- Impaired Biota Benthic Macroinvertebrates

Bioassessments

Cause Unknown

- Impaired Biota Biological

Cause Unknown

- Impaired Biota Biology

Cause Unknown

- Impaired Biota Estuarine Bioassessments

Cause Unknown

- Impaired Biota Fish Bioassessments

Cause Unknown

- Impaired Biota Fish Community Rated Poor

Cause Unknown

- Impaired Biota Impaired Biotic Communities

Dio xins 2,3,7,8

- Tetrachlorodibenzo

- P

- Dioxin (Only)

Dioxins Dioxin

Dioxins Dioxins

Fish Consumption Advisory Commercial Fishing Ban

Fish Consumption Advisory Fish Consumption Advisory

Flow Alteration(s) Flow Alteration(s)

Habitat Alterations Habitat

Habitat Alterations Habitat Alterations

Habitat Alterations Other Habitat Alteration(s)

Mercury Fish Advisories

- Mercury  

Mercury Fish Consumption Advisory

- Mercury  

Mercury Mercury  

Mercury Mercury In Fish Tissue  

Mercur y Methyl Mercury  

Metals (Other Than Mercury) Aluminum  

Metals (Other Than Mercury) Arsenic  

Metals (Other Than Mercury) Beryllium  

Metals (Other Than Mercury) Cadmium  

Metals (Other Than Mercury) Chromium  

Metals (Other Than Mercur y) Copper  



### B-1Appendix B

— Proximity Analyses Supporting Tables



### Table B-1. I mmediate Receiving Waters 303(d) Impairments Listing

Cause Group Name Cause Name Found in

Combustion

Wastewater Evaluated in

the EA
Metals (Other Than Mercury) Iron  

Metals (Other Than Mercury) Lead  

Metals (Other Than Mercury) Manganese  

Metals (Other Than Mercury) Metals (Other Than Mercury)  

Metals (Other Than Mercury) Selenium  

Metals (Other Than Mercury) Silver  

Metals (Other Than Mercury) Zinc  

Noxious Aquatic Plants Macrophytes

Noxious Aquatic Plants Noxious Aquatic Plants

Nuisance Exotic Species Exotic Species

Nutrients Eutrophication  

Nutrients Inorganic N  

Nutrients N itrates  

Nutrients Nitrogen, Total  

Nutrients Nutrient/Eutrophication Biological

Indicators  

Nutrients Nutrients  

Nutrients Phosphorus  

Nutrients Phosphorus, Total  

Oil And Grease Oil 

Oil And Grease Oil And Grease 

Organic En richment/Oxygen Depletion Carbonaceous Biochemical Oxygen Demand (BOD) 

Organic Enrichment/Oxygen Depletion Dissolved Oxygen 

Organic Enrichment/Oxygen Depletion Dissolved Oxygen Saturation 

Organic Enrichment/Oxygen Depletion Nitrogenous BOD 

Organic Enrichment/Oxygen Depletion Organic Enrichment/Low Dissolved Oxygen 

Pathogens Bacteria

Pathogens Bacterial Slimes

Pathogens Coliforms

Pathogens Enterococcus Bacteria

Pathogens Escherichia Coli ( E. Coli )

Pathogens Fecal Coliform

Pathogens Pathogens

Pathogens Total a nd Fecal Coliform

Pathogens Total Coliform

Pesticides Atrazine

Pesticides Chlordane



### B-2Appendix B

— Proximity Analyses Supporting Tables



### Table B-1. I mmediate Receiving Waters 303(d) Impairments Listing

Cause Group Name Cause Name Found in

Combustion

Wastewater Evaluated in

the EA

Pesticides Chlorpyrifos

Pesticides DDT ( D ichlorodiphenyltrichloroethane)

Pesticides Dieldrin

Pesticides Mire x

Pesticides Organochlorine Pesticides

Pesticides Pesticides

pH/Acidity/Caustic Conditions pH

Polychlorinated Biphenyls (PCBs) Commercial Fishing Ban

- PCBs

PCBs Fish Consumption Advisory

- PCBs

PCBs PCBs In Fish Tissue

PCBs PCBs

P CBs Priority Organics

- PCBs
Salinity/Total Dissolved

Solids/Chlorides/Sulfates Chloride  

Salinity/Total Dissolved

Solids/Chlorides/Sulfates Salinity/Total Dissolved

Solids/Chlorides  

Salinity/Total Dissolved

Solids/Chlorides/Sulfates Sulfates 

Salinity/Total Dissolved

Solids/Chlorides/Sulfates Total Dissolved Solids (TDS)  

Sediment Sediment

Sediment Sedimentation/Siltation 

Sediment Siltation 

Sediment Suspended Sediment 

Taste, Color, And Odor Taste, Color, a nd Odor

Temper ature Temperature

Temperature Thermal Modifications

Total Toxics Aquatic Toxicity

Total Toxics Toxics

Toxic Inorganics Boron  

Toxic Inorganics Cyanide 

Toxic Inorganics Other Inorganics

Toxic Organics Polycyclic Aromatic Hydrocarbons (PAHs) (Aquatic Ecosystems)
Toxic Organics Priority Organic Compounds

Turbidity Suspended Solids 

Turbidity Total Suspended Solids (TSS) 

Turbidity Turbidity 

Source: 303(d) Listed Impaired Waters National Hydrography Data ( NHD ) Indexed Data set. Reach Address Database (RAD). Extracted on March 31, 2011. Available online at: http://www.epa.gov/waters/data/downloads.html

. (DCN SE03556).



### B-3Appendix B

— Proximity Analyses Supporting Tables



### Table B-2. Immediate Receiving Waters Fish Consumption Advisory Listing

Pollutant Found in Combustion

Wastewater Evaluated in the EA a

Cadmium  

Chlordane

Chlorinated pesticides

DDT

Dieldrin

Dioxin

Lead  

Mer cury  

Mirex

Not Specified

PCBs (Total)

Perfluorooctane sulfonate

Toxaphene

Source : Fish Consumption Advisories NHD Indexed Dataset. RAD. Available online at:
http://epamap32.epa.gov/radims/

. (DCN SE03558).

a – The number and percentage of immediate receiving waters issued a fish consumption advisory for the pollutants evaluated in the EA are presented in Table 3

- 12.



### B-4Appendix C

— Water Quality Model Methodology



# APPENDIX C WATER QUALITY MODEL METHODOLOGY

This appendix presents the model equations, input values (including site

- specific default model assumption values) and pollutant benchmarks, and methodology limitations/assumptions for the water quality model.

The water quality model equations are organized by the methodology for nonvolatile metals (i.e., arsenic, cadmium, chromium (VI), copper, lead, nickel, selenium, thallium, and zinc) and volatile metals (i.e., mercury). The U.S. Environmental Protection Agency (EPA) used the equations to calculate total and dissolved receiving water conc entrations and total sediment concentrations in the immediate discharge zone. Model input requirements for the equations presented in Appendix C can be divided into four major categories: (1) input variable described by another equation; (2) site

- specific input value; (3) default model assumption value; and (4)

site

- specific assumption value based on predetermined data. The following tables in Appendix C describe the input requirements and data sources used in the water quality model:

• Table C- 1 . Site

- Specif ic Model Input Variables;

• Table C-2. Default Model Assumption I nput Variables ;

• Table C-3

. Site

- Specific Model Assumption I nput Variables ;

• Table C-4 . Surface Water Partition Coefficients;

• Table C-5 . Total Suspended Solids (TSS) Concentrations in Lakes and R ivers;

• Table C-6 . Regional Surface Water Temperatures; and

• Table C-7 . National Recommended Water Quality Criteria (NRWQC) and Drinking Water Maximum Contaminant Level (MCL) Benchmarks.

EPA used the immediate receiving

- water

- specific pollutant loading value s for total metals in the water quality model, except for chromium VI. EPA estimated the total pollutant loading from the evaluated waste streams on a per immediate

- receiving

- water basis. However, some plants discharge to multiple receiving waters and ther efore, EPA divided the plant

- specific loadings accordingly among the receiving waters based on water diagrams provided in Questionnaire for the Steam Electric Power Generating Effluent Guidelines (Steam Electric Survey) responses. EPA evaluated the environmental impacts from 281 steam electric power plants in the receiving water quantitative analysis (297 unique immediate receiving waters).

EPA modeled chromium VI in the water quality model, but did not take into consideration arsenic or mercury speciatio n in the water quality model. EPA included assumptions of metal speciation as appropriate in the subsequent wildlife and human health models (see Appendix D and Appendix E , respectively). EPA used total selenium loadings in the water quality model; however , due to the partition coefficients available, EPA assumed the dominant form of selenium in the receiving water was selenate (i.e., selenium VI). Although selenium speciation likely occurs within combustion residuals surface impoundments prior to discharge , EPA selected the selenate partition coefficient because it is expected to be the predominant form present in well

- oxygenated alkaline surface waters and the rate of conversion

C-1Appendix C

— Water Quality Model Methodology



### between selenate and selenite (i.e., selenium IV) is reported to be slow in most natural waters [U.S. EPA, 2004].

Water Quality Model Equations

EPA calculated the nonvolatile metal concentrations for the following compartments within the receiving water:

• Total pollutant concentration in water column (C

wc 

### );

• Dissolved pollutant concen tration in water column (C dw 

### ); and

• Total pollutant concentration in sediment (C bs 

### ).

EPA used the equations presented below to calculate receiving water concentrations for arsenic, cadmium, chromium (VI), copper, lead, mercury, nickel, selenium, thallium, a nd zinc discharging.

EQUATION C -1

L total



### = Cw Tot, Rivers 

### ( Q cool 

### + Q ) × f water 

### + K wt 

### × V river river 

### where:

Cw Tot,Rivers 

### = Total water body concentration (water and sediment) in rivers and streams from

l oading (grams per cubic meter [g/m 3 

### ] or milligrams per liter [mg/L]) Output from Equation C -1

L total 

### = Total metal loading from steam effluent (grams per day [g/day]) Output from engineering analysis (see Table C

- 1 )

Q cool 

### = Total cooling water effluent flow (cubic meters per day [m 3 

### /day]) Output from engineering analysis (see Table C

- 1 )

Q river 

### = Receiving water average annual flow (m 3 

### / day) NHD Plus (see Table C

- 1 )

f water 

### = Fraction of contaminant in water column (unitless) Output from Equation C-6

K

wt 

### = Water concentration dissipation rate constant (1 /day) Output from Equation C-10

V river 

### = Flow independent mixing volume for rivers (m 3 

### ) Output from Equation C-11

C-2Appendix C

— Water Quality Model Methodology



### EQUATION C- 2

L total 

### Cw To t, Lake 

### = ( Q cool 

### + Q lake 

### ) × f water 

### + K wt 

### × V lake 

### where:

Cw Tot, Lake 

### = Total water body concentration (water and sediment) in lakes from loading (g/m 3 

### or mg/L) Output from Equation C -1

L total 

### = Total metal loadi ng from steam effluent (g/day) Output from engineering analysis ( see Table C- 1)

Q cool 

### = Total cooling water effluent flow (m 3 

### /day) Output from engineering analysis (see Table C- 1)

Q lake 

### = Average annual flow for rivers and streams exiting the lake (m 3 

### /day) NHD Plus (see Table C

- 1 )

f water 

### = Fraction of contaminant in water column (unitless) Output from Equation C -6

K

wt 

### = Water concentration dissipation rate constant (1/day) Output from Equation C-10

V lake 

### = Flow independent mixing volume (m 3 

### ) Output from Equation C

- 11

EQUATION C- 3
d

z 

### C

wc 

### = f water 

### × Cw tot (Rivers or Lakes) 

### × d

w 

### where:

C

wc 

### = Total pollutant concentration in water (mg/L) Output from Equation C

- 3

f

wa ter 

### = Fraction of total water body contaminant in water column (unitless) Output from Equation C

- 6

Cw Tot

(Rivers or

Lakes) 

### = Total water body concentration (water and sediment) in rivers or lakes from loading (g/m 3 

### or mg/L) Output from Equation C

- 1

or Equation C

- 2

d

z 

### = Depth of the water body (meters [m]) Output from Equation C

- 9

d

w 

### = Depth of water column (m) River or stream output from Equation C-7

Lake or Pond

Site

- specific value 2

2 For lakes, ponds, and reservoirs, EPA used site

- specific values for the depth of the water body. See the ERG memorandum Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a] for further details.



### C-3

### C dw 

### = C

wc 

### 1

1 + Kd

sw 

### × TSS × 0.000001 ൬ ൰

d

w 

### 1 + Kd

sw 

### × TSS × 0.000001 × d

z



### = r 

### d

w 

### d b 

### ቈ [ 1 + ( Kd

sw 

### × TSS × 0.000001 )] × ቉

+ ൤ ( bsp + Kd bs 

### × bsc ) × ൨

d

z 

### d

z Appendix C

— Water Quality Model Methodology



### EQUATION C-4

where:

C dw 

### = Disso lved pollutant concentration in water (mg/L) Output from Equation C

- 4

C

wc 

### = Total pollutant concentration in water (mg/L) Output from Equation C

- 3

Kd

sw 

### = Suspended sedim ent

- surface water partition coefficient (milliliters per gram [mL/g]) Assumed value (see Table C-2 and Table

C

- 4 )

TSS = Total suspended solids (mg/L) Assumed value ( see Table C-3 and Table

C

- 5 )

0.000001 = Conversion factor (L/mL)(g/mg) Conversion fact or

EQUATION C-5
d

z 

### C bs 

### = f Benth 

### × Cw tot (Rivers or Lakes) 

### × d b 

### where:

C bs 

### = Total pollutant concentration in sediment (mg/L) Output from Equation C-5

f Benth 

### = Fraction of total water body contaminant in benthic sediments (unitless) Output from Equ ation C-15

Cw Tot

(Rivers or

Lakes) 

### = Total water body concentration (water and sediment) in rivers or lakes from loading (g/m 3 

### or mg/L) Output from Equation C

- 1

or Equation C

- 2

d

z 

### = Depth of the water body (m) Output from Equation C

- 9

d

b 

### = Depth of upper benthic layer (m) Assumed value of 0.03 m (see Table C

- 2 )

EQUATION C-6

[ ( )]

f wate



### where:

f water 

### = Fraction of contaminant in water column (unitless) Output from Equation C-6

C-4Appendix C

— Water Quality Model Methodology



### Kd

sw 

### = Suspended sediment

- surface water partition coefficient (mL/g) Assumed value (see Table C-2 and Table

C

- 4 )

TSS = Total suspended solids (mg/L) Assumed value ( see Table C-3 and Table

C

- 5 )

0.000001 = Conversion factor (L/mL)(g/mg) Conversion factor

d

w 

### = Depth of water column (m) River or stream output from Equation C-7

Lake or pond

site

- specific value 3



### d

z 

### = Depth of the water body (m) Output from Equation C

- 9

bsp = Bed sediment porosity (cubic centimeter per cubic centimeter [cm 3 

### /cm 3 

### ]) Assumed value of 0.6

cm 3 

### /cm 3


### (see Table C

- 2 )

Kd bs 

### = Bottom sediment

- pore water partition coefficient (mL/g) Assumed va lue (see Table C-2 and Table

C

- 4 )

bsc = Bed sediment particle concentration (gram per cubic centimeter [g/cm 3 

### ]) or (kilogram per liter [kg/L]) Assumed value of 1 g/cm 3


### (see Table C-2)

d

b 

### = Depth of upper benthic layer (m) Assumed value of 0.03 m (see Table C

- 2 )

EQUATION C-7

d

w 

### = Q river



### v × Width where:

d

w 

### = Depth of water column (m) Output from Equation C

- 7

Q river 

### = Receiving water flow (m 3 

### /s) NHD Plus (see Table C

- 1 )

v = Receiv ing water velocity (m/s) NHD Plus (see Table C

- 1 )

Width = Receiving water width (m) Output from Equation C

- 8

3 For lakes, ponds, and reservoirs, EPA used site

- specific values for the depth of the water body. See the ERG memorandum Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a] for further details.



### C-5Appendix C

— Water Quality Model Methodology



### EQUATION C-8

0.4559 

### Width = 5.1867 × Q river 

### where:

Width = Receiving water width (m) Output from Equation C

- 8

Q river 

### = Receiving water flow (m 3 

### /s) NHD Plus (see Table C

- 1 )

EQUATION C-9

d

z 

### = d b 

### + d

w 

### where:

d

z 

### = Depth of the water body (m) River or stream output from Equation C-9

Lake or pond

site

- specific value (see Table C

- 1 ) 4



### d

b 

### = Depth of upper benthic layer (m) Assumed value 0.03 m (see Table C

- 2 )

d

w 

### = Depth of water column (m) River or stream output from Equation C-7

Lake or pond

site

- specific value 5



### EQUATION C-10

K

wt 

### = ( f water 

### × k

sw 

### ) + ( f benth 

### × k sed 

### ) + ( f water 

### × k vol 

### ) + ( f benth 

### × K b 

### )

where:

K wt 

### = Water concentration dissipation rate constant (1/day) for nonvolatile metals (see Equation

C

- 16 for volatile metals) Output from Equation C-10

f water 

### = Fra ction of total water body contaminant in water column (unitless) Output from Equation C-6

k

sw 

### = Degradation rate for water column (1/day) Assumed value of 0/day (see Table C

- 2 )

4 For lakes, ponds, and reservoirs, EPA used site

- specific values for the depth of the water body. See the ERG memorandum Water Quality Model: Plant and Receiving Water Character istics [ERG, 2013a] for further details.

5 For lakes, ponds, and reservoirs, EPA used site

- specific values for the depth of the water body. See the ERG memorandum Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a] for further deta ils.



### C-6Appendix C

— Water Quality Model Methodology



### f benth 

### = Fraction of total water body contaminant in benthic sediments (uni tless) Output from Equ ation C-15

k sed 

### = Degradation rate for sediment (1/day) Assumed value of 0/day (see Table C

- 2 )

k

vol 

### = Water column volatilization loss rate constant (1/day) Assumed value of 0/day (see Table C

- 2 )

K

b 

### = Benthic burial rate consta nt (1/day) Output from Equation C

- 14

EQUATION C-11

V river 

### = Width × Len × d

z 

### where:

V river 

### = Flow independent mixing volume for rivers and streams (m 3 

### ) Output from Equation C-11

Width = Receiving water width (m) Outp ut from Equation C

- 8

Len = Length of stream reach (m) NHD Plus (see Table C

- 1 )

d

z 

### = Depth of the water body (m) Output from Equation C

- 9

EQUATION C-12

V lake 

### = Area × d z,lake 

### where:

V lake 

### = Flow independent mixing vol ume for lakes and ponds (m 3 

### ) Output from Equation C-12

Area = Surface area of the lake (m) NHD Plus (see Table C

- 1 )

d z,lak e 

### = Depth of the lake (m) Site

- specific evaluations (see Table C

- 1 )

EQUATION C-13

f d 

### = 1

1 + Kd

sw 

### × TSS × 0.000001

where:

f d 

### = Dissolved fraction in water (unitless) Output from Equation C

- 13

Kd

sw 

### = Suspended sediment

- surface water partition coefficient (mL/g) Assumed value (see Table C-2 and Table

C

- 4 )

C-7Appendix C

— Water Quality Model Methodology



### TSS = Total suspended solids (mg/L ) Assumed value (see Table C-3 and Table

C

- 5 )

0.000001 = Conversion factor (L/mL)(g/mg) Conversion factor

EQUATION C-14

K b 

### = f benth 

### × WB

d

b 

### where:

K b 

### = Benthic burial rate constant (1/day) Output from Equation C

- 14

f Benth 

### = Fraction of contaminant in benthic sediments (unitless) Output from Equ ation C-15

WB = Rate of burial (m/day) Assumed value of 0 m/day (see Table C

- 2 )

d

b 

### = Depth of upper benthic layer (m) Assumed value of 0.03 m (see Table C

- 2 )

EQU ATION C-15

d b 

### ( bsp + Kd bs 

### × bsc ) × d

z 

### f Benth 

### = d

w 

### d b 

### ቈ [ 1 + ( Kd

sw 

### × TSS × 0.000001 )] × ቉

+ ൤ ( bsp + Kd bs 

### × bsc ) × ൨

d

z 

### d

z 

### where:

f Benth 

### = Fraction of total water body contaminant in

benthic sediments (unitless) Output from Equ ation C

- 15

bsp = Bed sediment porosity (cm 3 

### /cm 3 

### ) Assumed value of 0.6

cm 3 

### /cm 3


### (see Table C

- 2 )

Kd bs 

### = Bottom sediment

- pore water partition coefficient (mL/g) Assumed value (see Table C-2 and Table

C

- 4 )

bsc = Bed se diment particle concentration (g/cm 3 

### ) or (kg/L) Assumed value of 1 g/cm 3


### (see Table C

- 2 )

d

b 

### = Depth of upper benthic layer (m) Assumed value of 0.03 m (see Table C

- 2 )

d

z 

### = Depth of the water body (m) Output from Equation C

- 9

Kd

sw 

### = Suspended sediment

- surface water partition coefficient (mL/g) Assumed value (see Table C-2 and Table

C

- 4 )

C-8Appendix C

— Water Quality Model Methodology



### TSS = Total suspended solids (mg/L) Assumed value (see Table C-3 and Table

C

- 5 )

0.000001 = Conversion factor (L/mL)(g/mg) Conversion factor

d

w 

### = Depth of water co lumn (m) River or stream output from Equation C-7

Lake or pond

site

- specific value 6



### EPA calculated the volatile metal concentrations in each of the three compartments within the receiving water by building off the equations used to calculate nonvolat ile metal

concentrations. K wt 

### in Equation C-10 was replaced with a K wt 

### factor (see Equation C-16 ) that takes into account volatilization (k vol 

### ). EPA used the equations presented below to calculate receiving water concentrations for mercury only.

EQUATION C-16

K

wt, volatile 

### = ( f water 

### × k

sw 

### ) + ( f benth 

### × k sed 

### ) + ( f water 

### × f d 

### × k vol 

### ) + ( f benth 

### × K b 

### )

where:

K

wt, volatile 

### = Water concentration dissipation rate constant (1/day) Output from Equation C-16

f water 

### = Fraction of contaminant in water column (unitless) Output from Equation C-6

k

sw 

### = Degradation rate for water column (1/day) Assumed value of 0/day (see Table C

- 2 )

f benth 

### = Fraction of contaminant in benthic sediments (unitless) Output f rom Equ ation C-15

k sed 

### = Degradation rate for sediment (1/day) Assumed value of 0/day (see Table C

- 2 )

f d 

### = Dissolved fraction in water (unitless) Output from Equation C

- 13

k

vol 

### = Water column volatilization loss rate constant (1/day) Output from Equation C-17

K

b 

### = Benthic burial rate constant (1/day) Output from Equation C

- 14

EQUATION C-16

K

v 

### × f d



### = k

vol 

### d

w

6 For lakes, ponds, and reservoirs, EPA used site

- specific values for the depth of the water body. See the ERG memorandum Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a] for further details.



### C-9

### 1 T w -T hic 

### K

v 

### = θ water 

### ቀ 1 ቁ + ൮

1 ൲

K

L 

### K g 

### × HLC

R × T

w Appendix C

— Water Quality Model Methodology



### where:

k

vol 

### = Water column volatilization loss rate constant (1/day) Output from Equation C-17

K

v 

### = Diffusion transfer rate (m/day) Output from Equat ion C

- 18

f d 

### = Dissolved fraction in water (unitless) Output from Equation C

- 13

d

w 

### = Depth of water column (m) River or stream output from Equation C-7

Lake or pond

site

- specific value 7



### EQUAT ION C-17

where:

K

v 

### = Diffusion transfer rate (m/day) Output from Equat ion C

- 18

Θ water 

### = Temperature correction (unitless) Assumed value of 1.026 (see Table C

- 2 )

T

w 

### = Temperature of the water body (degrees Kelvin [°K]) Assumed value (se e Table C-3 and Table

C

- 6 )

T hlc 

### = Temperature of HLC (°K) Assumed value of 298 (see Table C

- 2 )

K

L 

### = Liquid

- phase transfer coefficient (m/day) River or stream output from Equation C-19

Lake or pond output from Equation C

- 21

K g 

### = Gas

- phase transfer coe fficient (m/day) River or stream assumed value of 100 m/day (see Table C-2)

Lake or pond output from Equation C

- 23

7 For lakes, ponds, and reserv oirs, EPA used site

- specific values for the depth of the water body. See the ERG memorandum Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a] for further details.



### C-10

### × ቆ k 0.33

a 

### K

L ( Lakes ) 

### = ඥ c d 

### × w 10 

### × ඨ ρ ቇ

× Sc

w - 0.67 

### × 86,400 ρ λ 2

w Appendix C

— Water Quality Model Methodology



### HLC = Henry's Law Constant (atm -m 3 

### /mole) 8 

### Assumed value of 0.0113

atm -m 3 

### /mol (see Table C

- 2 )

R = Ideal gas constant (atm -m 3 

### /°K- mole) Assumed value of

0.00008205 (see Table C

- 2 )

EQUATION C-18

= ඨ 10 -4 

### × D

w 

### × v K L(Rivers) 

### × 86,400 d

z 

### where:

K

L(Rivers) 

### = Liquid

- phase transfer coefficient (m/day) River or stream output from Equation C

- 19

D

w 

### = Diffusivity of the chemical in water (square centimeter per second [cm 2 

### /s]) Output from Equation C-20

v = Receiving water velocity (m/s) NHD Plus (see Table C

- 1 )

d

z 

### = Depth of water body (m) Output from Equation C

- 9

86,400 = Conversion factor ( s/day) Conversion factor

EQUATION C-19

22×10 -5


### D

w 

### = ⁄ 

### MW 2 3



### where:

D

w 

### = Diffusivity of the chemical in water (cm 2 

### /s) Output from Equation C

- 20

MW = Molecular weight Known value (see Table C

- 2 )

EQUATION C-20

8 Units for Henry’s Law Constant are atmospheres of absolute press ure (atm) per cubic meter (m 3 ) per mole (mol).



### C-11

### = ඥ C d 

### × W 10 

### × ቆ k 0.33

- 0.67 

### × 86,400 K

g(Lakes) 

### ቇ

× Sc

a 

### λ 2 Appendix C

— Water Quality Model Methodology



### where:

K

L(Lakes) 

### = Liquid

- phase transfer coefficient (m/day) Lake or pond output from Equation C

- 21

C d 

### = Drag coefficient (unitless) Assumed value of 0.0011 (see Table C

- 2 )

W 10 

### = Wind velocity 1 0 meters above water surface (m/s) Site

- specific data (see Table C

- 3 )

ρ a 

### = Density of air corresponding to water temperature (g/cm 3 

### ) Assumed value of 0.0012 g/cm 3


### (see Table C

- 2 )

ρ w 

### = Density of water corresponding to water temperature (g/cm 3 

### ) Assumed va lue of 1 g/cm 3


### (see Table C

- 2 )

k = Von Karman’s constant (unitless) Assumed value of 0.4 (see Table C

- 2 )

λ 2 

### = Dimensionless viscous sublayer thickness (unitless) Assumed value of 4 (see Table C

- 2 )

Sc

w 

### = Water Schmidt number (dimensionless) Output from Equation C

- 22

86,400 = Conversion factor (s/day) Conversion factor

EQUATION C-21

μ

w 

### Sc

w 

### = ρ × D

w w 

### where:

Sc

w 

### = Water Schmidt number (dimensionless) Output from Equation C

- 22

μ w 

### = Viscosity of water corres ponding to water temperature (g/cm

- s) Assumed value of 0.0169 g/cm-s (see Table C

- 2 )

ρ w 

### = Density of water corresponding to water temperature (g/cm 3 

### ) Assumed value of 1 g/cm 3


### (see Table C

- 2 )

D

w 

### = Diffusivity of the chemical in water (cm 2 

### /s) Output from Equation C

- 20

EQUATION C-22

C-12Appendix C

— Water Quality Model Methodology



### where:

K g(lakes) 

### = Gas

- phase transfer coefficient (m/day) Lakes and ponds output from Equation C

- 23

C d 

### = Drag coefficient (unitless) Assumed value of 0.0011 (see Table C

- 2 )

W 10 

### = Wind velocity 10 meters above water surface (m/s) Site

- specific data (see Table C

- 3 )

k = Von Karman’s constant (unitless) Assumed value of 0.4 (see Table C

- 2 )

λ 2 

### = Dimensionless viscous sublayer thickness (unitless) Assumed value of 4 (see Table C

- 2 )

Sc

a 

### = Air Schmidt number (dimensionless) Output from Equation C

- 24

86,400 = Conversion factor (s/day) Conversion factor

EQUATION C-23

( 1.32 + 0.009T

a 

### ) × 10 5


### Sc

a 

### = 1.9

MW 2 3 ⁄



### where:

Sc

a 

### = Air Schmidt number (dimensionless) Output from Equation C

- 24

T
a 

### = Air temperature °K Site

- specific data (see Table C

- 3 )

MW = Molecular weight Known value (see Table C

- 2 )

EPA calculated the potential negative impact to aquatic organisms from direct contact with the surface water of receiving water bodies using the equation presented below.

EQUATION C-24

C

w c 

### HQ = sw 

### CSCL

sw 

### where:

HQ

sw 

### = Hazard quotient for contact with surface

water Output from Equation C -25

C

wc 

### = Total pollutant concentration in water (mg/L) Output from Equation C -3

CSCL

sw 

### = Ecological benchmark for surface water (mg/L) Receptor

- specific assumed

value (see Table C

- 2 and Table C

- 7 )

C-13Appendix C

— Water Quality Model Methodology



### Water Quality Model Inputs

Table C-1 . Site

- Specific Model Input Variables

Input

Variable Input Category and Description Data Source

L total Plant

- specific effluent characteristic

Total water body loading EPA estimated the pollutant discharge loadings using the methodology presented in Section 10 of the Steam Electric Power Generating Point Source Category TDD [U.S. EPA, 2013b].

Q cool Plant

- specific effluent characteristic

Total cooling water effluent flow by receiving water EPA determined the estimated cooling water flow for each plant by outfall based an assessment of industry survey results using the methodology outlined in Water Qu ality Model: Plant and Receiving Water Characteristics [ERG, 2013a].

Q river Receiving water characteristic for

rivers and streams

Water body annual flow EPA extracted average annual flow values from the NHD Plus dataset using the methodology outlined i n Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a]. The NHD Plus dataset includes estimated mean annual flow values for each stream reach within the network using the Vogel Method [Vogel et al., 1999].

v Receiving water characte ristic for

rivers and streams

Receiving water velocity EPA extracted average annual velocity values from the NHD Plus dataset using the methodology outlined in Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a]. The NHD Plus dataset includes estimated mean annual velocity values for each stream reach within the network using the Jobson Method (Jobson, 1996).

Len Receiving water characteristic for

rivers and streams

Length of stream reach EPA est imated the stream reach length based on outfall locations using the methodology described in Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a].

Q lake Receiving water characteristic for lakes, ponds, and reservoirs

Average discharge flow exiting the lake/pond system EPA extracted average annual flow values from the NHD Plus dataset using the methodology outlined in Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a]. The NHD Plus dataset includes estimated mean annual flow values for the stream reach exiting the lake using the Vogel Method (Vogel et al., 1999).

Area Receiving water characteristic for lakes, ponds, and reservoirs

Surface area of the lake, pond, or

reservoir EPA estimated the lake surface area based on NHD Plus data

or site

- specific sources as described in Water Quality Model: Plant and Receiving Water Characteristics [ERG, 2013a].

d z,lake Receiving water characteristic for lakes, ponds, and reservoirs

Depth of the lake, pond, or

reservoir EPA estimated the depth of the lake based on site

- specific data

as described in Water Quality Model: Plant and Receiving

Water Characteristics [ERG, 2013a].



### C-14Appendix C

— Water Quality Model Methodology



### Table C-2 . Default Model Assumption Input Values

Input Variable Description Assumed

Value Assumption Rationale

b sp Bed sediment porosity 0.6 cm 3 /cm 3 Bed sediment porosity is the volume of water per volume of benthic space with typical values ranging between 0.8 and 0.4 [U.S. EPA, 1998b]. EPA selected an average value to use for this input variable.

bsc Bed sedimen t particle

concentration 1 g/cm 3 Bed sediment particle concentrations typically range between 0.5 to 1.5 g/cm 3 [U.S. EPA, 1998d]. EPA selected an average value to use for this input variable.

d

b Depth of upper benthic layer 0.03 m The upper benthic laye r variable represents the portion of the bed in equilibrium with the water column. Typical values can range from 0.01 to 0.05 m (U.S. EPA, 1998b). EPA selected an average value to use for this input variable.

k

sw Degradation rate for water

column 0/day EP A did not assume any loss from metal degradation in the water column, as an environmentally conservative assumption.

k

vol Water column volatilization

rate constant 0/day EPA selected a volatilization rate of 0 for

nonvolatile metals.

k sed Degradation r ate for

sediment 0/day EPA did not assume any loss from metal degradation in the sediment, as an environmentally conservative assumption.

WB Rate of burial 0/day EPA did not assume any metal loss from burial within the water body sediments, as an

environ mentally conservative assumption,

Θ water Temperature correction 1.026
unitless EPA selected the temperature correction factor based on the value provided in U.S. EPA, 1998b.

K g(Rivers) Gas phase transfer

coefficient for rivers or

streams 36,500 m/yr (100 m/day) EPA selected the gas pha se transfer coefficient

for rivers and streams based on the value provided in U.S. EPA, 1998b.

R Ideal gas constant 0.00008205

atm -m 3 /

K

- mole The ideal gas constant is a known chemical

constant.

C d Drag coefficient 0.0011

unitless EPA selected the drag coefficient based on the value provided in U.S. EPA, 1998b.

ρ a Density of air corresponding to water
temperature 0.0012 g/cm 3 EPA selected the density of air corresponding to water temperature based on the value provided in U.S. EPA, 2005b.

ρ w Density of water corresponding to water
temperature 1 g/cm 3 EPA select ed the density of water corresponding to water temperature based on the value provided in U.S. EPA, 2005b.

k Von Karman’s constant 0.4

unitless The von Karman constant is a known

dimensionless constant used to describe the velocity profile of a turbulent fluid flow near a boundary.

Kd

s Sediment

- surface water partition coefficient Table C

- 4 The surface water partition coefficient describes the partitioning of a contaminant between sorbing material, in this case bottom sediment,

and surface water. EPA iden tified U.S. EPA, 2005 as the primary source for the metal

- specific surface water partition coefficients.



### C-15Appendix C

— Water Quality Model Methodology



### Table C-2 . Default Model Assumption Input Values

Input Variable Description Assumed

Value Assumption Rationale

Kd

sw Suspended sediment

surface water partition

coefficient Table C

- 4 The suspended sediment partition coefficient describes the partitioning of a contaminant between sorbing material, in this case suspended sediment, and surface water. EPA identified U.S. EPA, 2005 as the primary source for the metal

specific suspended sediment partition

coefficients.

Kd bs Bottom sediment

- water partition coefficie nt Table C

- 4 The bottom sediment partition coefficient describes the partitioning of a contaminant between sorbing material, in this case bottom sediment, and surface water. EPA identified U.S. EPA, 2005 as the primary source for the metal

specific bed sed iment partition coefficients.

λ

2 Dimensionless viscous sublayer thickness 4

unitless EPA selected the viscous sublayer thickness value based on the value provided in U.S. EPA,

2005b.

μ w Viscosity of water corresponding to water
temperature 0.0169 g/cm -s EPA selected the viscosity of w ater value based on the value provided in U.S. EPA, 2005b.

HLC Henry’s Law Constant 0.0113

atm -m 3 /mol Henry’s Law Constant is used in Equat ion C

- 18 to estimate the receiving water concentration for volatile metals. Mercury is the only volatile

metal incl uded in the water quality model. Therefore, the assumed model default value is set to Henry’s Law Constant for mercury at 298

°K.

T hlc Temperature of Henry’s

Law Constant 298 The value 298 °K is the standard temperature value provided for Henry’s Law Cons tant.

MW Molecular weight 200.59 g/mol Molecular weight is used in Equation C

- 20 and Equation C-24 to estimate the receiving water concentration for volatile metals. Mercury is the only volatile metal included in the water quality model. Therefore, the as sumed model default value is set to the molecular weight for mercury.

CSCL

sw Ecological benchmark for

surface water Table C

- 7 U.S. EPA, 2009d and 2009e.



### Table C-3. Site

- Specific Mo del Assumption Input Values

Input Variable Description Assumed

Value Data Source

TSS Total suspended solids Table C

- 5 EPA used the geometric mean of the regional and national TSS concentrations determined as part of

the CCW Risk Assessment [U.S. EPA, 201 0b; Chapter 6 of U.S. EPA, 1999].



### C-16Appendix C

— Water Quality Model Methodology



### Table C-3. Site

- Specific Mo del Assumption Input Values

Input Variable Description Assumed

Value Data Source

W 10 Wind velocity 10 m above

the water surface Table C

- 1 National Climatic Data Center national mean annual wind speed GIS coverage (downloaded

05/12/2011 from http://hurricane.ncdc.noaa.gov/cgi

bin/climaps/climaps.pl?directive=quick_search&s

ubrnum =). EPA selected, as an environmentally conservative estimate, the lower of the wind speed range values for the analysis.

T

a Air temperature Table C

- 2 National Climatic Data Center national mean annual temperature GIS coverage (downloaded

05/12/2011 from http://hurricane. ncdc.noaa.gov/cgi

bin/climaps/climaps.pl?directive=quick_search&s

ubrnum =). EPA selected, as an environmentally conservative estimate, the lower of the air temperature range values for the analysis.

T

w Temperature of the water body Table C

- 6 EPA used the regional surface temperatures determined as part of the CCW Risk Assessment [U.S. EPA, 2010b; Chapter 6 of U.S. EPA, 1999b].



### Figure C

- 1. National Climatic Data Center National Mean Annual Wind Speed

C-17Appendix C

— Water Quality Model Methodology



### Figure C

- 2. National Climatic Data Center Nationa l Mean Annual Temperature

Table C-4 . Surface Water Partition Coefficients

Pollutant Sediment

- Surface Water

Partition Coefficient (Kd

s ) (mg/L) Suspended Sediment

- Surface

Water Partitio n Coefficient (Kd

sw ) (mg/L) Bottom Sediment

- Pore

Water Partition

Coefficient (Kd bs )

Arsenic 3.2 3.9 2.4

Cadmium 2.7 4.9 3.3

Chromium (VI) 0.8 4.2 1.7

Copper 2.5 4.7 3.5

Lead 3.7 5.7 4.6

Mercury (II) 3.6 5.3 4.9

Nickel 2.9 4.3 3.9

Selenium (IV) 1.3 4.4 3.6

Thallium 0.5 4.1 1.3

Zinc 2.7 5.0 4.1

Source: U.S. EPA, 2005.



### Table C-5 . TSS Concentrations in Lakes and Rivers

Hydrologic

Region Number of

Measurements Number of

Annual M edians Annual Median TSS (mg/L) (log triangular distribution)

Min Max Geometric

Mean Weighted

Geometric

Mean

1 9,007 33 3.2 40 8 6

2 47,202 38 10 316 32 40

3 43,395 36 6.3 79 25 25

4 29,577 37 6.3 794 25 25

5 39,900 38 4 100 25 25



### C-18Appendix C

— Water Quality Model Methodology



### Table C-5 . TSS Concentrations in Lakes and Rivers

Hydrologic

Region Number of

Measurements Number of

Annual M edians Annual Median TSS (mg/L) (log triangular distribution)

Min Max Geometric

Mean Weighted

Geometric

Mean

6 4,137 28 5 31 6 16 20

7 34,494 37 32 1,585 63 100

8 46,231 38 50 316 158 126

9 3,254 35 13 3,162 32 63

10 62,791 38 10 398 126 126

11 48,969 38 25 794 200 126

12 7,280 35 40 1,995 79 126

13 13,974 37 32 79,433 200 398

14 26,699 38 16 5,012 158 251

15 9,162 37 2 0 19,953 200 398

16 19,965 33 4 2,512 16 25

17 173,136 37 2 316 6 10

18 42,022 37 13 398 63 50

Lakes (national) 4,360 99 1 398 25 25

Source: U.S. EPA, 2010b; Legacy STORET database.



### Table C-6. Regional Surface Water Temperatures

Hydrologic Region Climate Surface Water Temperature (°C)

1 North 14 (Northern Median)

2 North 16

3 South 21

4 North 14

5 North 17

6 South 18

7 North 15

8 South 20

9 North 10

10 North 13

11 South 17

12 South 21

13 South 17 (Southern Median)

14 South 9

15 South 17

16 South 9

17 North 14 (Northern Median)

18 South 15

Source: U.S. EPA, 2010b; Legacy STORET database.



### C-19Appendix C

— Water Quality Model Methodology



### Table C-7 . NRWQC and MCL Benchmarks

Pollutant FW Acute NRWQC

Benchmark a,b
(mg/L) FW Chronic NRWQC

Benchmark a,b
(mg/L) HH WO NRWQC

Benchmark a,b
(mg/L) HH O NRWQC

Benchmark a,b
(mg/L) MCL

Benchmark a,c (mg/L)

Dissolved

Arsenic 0.34 0.15

- - -

Total

Ar senic - - 0.000018 0.00014 0.01

Dissolved

Cadmium 0.002 0.00025

- - -

Dissolved

Chromium VI 0.016 0.011

- - -

Total

Chromium VI - - - - 0.1

Dissolved Copper 0.013 0.009

- - -

Total Copper - - 1.3

- 1.3

Dissolved

Lead 0.065 0.0025

- - -

Dissolved Mercury 0.0014 0.00077

- - -

Total Mercury - - - - 0.002

Dissolved

Nickel 0.47 0.052

- - -

Total

Nickel - - 0.61 4.6

-

Total

Selenium - 0.005 0.17 4.2 0.05

Total

Thallium - - 0.00024 0.00047

-

Dissolved

Zinc 0.12 0.12

- - -

Total

Zinc - - 7. 4 26

-

Acronyms: MCL (Maximum Contaminant Level); NRQWC (National Recommended Water Quality Criteria).

a – Designates instances where a benchmark does not exist for the pollutant or the benchmark is a secondary standard.

b – National Recommended Water Qua lity Criteria. Washington, D.C. [U.S. EPA, 2009d]. Pollutant concentrations were compared to the freshwater (FW) acute and chronic NRWQC and the human health (HH) water and organisms (WO) and organisms only (O) NRWQC.

c – National Primary Drinking Water Re gulations. EPA 816 -F-09- 004. May. Washington, D.C. [U.S. EPA, 2009e].



### Water Quality Model Methodology Limitations and Assumptions

The limitations and assumptions in the water quality model are as follows:

• 

### The model is based on average annual loadings an d effluent flows and does not consider temporal variability (e.g., seasonal differences, storm flows, low

- flow events, catastrophic events).

C-20Appendix C

— Water Quality Model Methodology



### • 

### The model represents only the water body concentration within the immediate discharge zone (i.e., approximately 1 t o 10 kilometers [km] from the outfall) and does

not calculate metal concentrations in downstream waters.

• 

### The model does not take into consideration metal speciation within the receiving stream. This assumption/limitation is particularly relevant to the wil dlife impact analysis as many of the ecological impacts are tied to a specific metal species. For example, inorganic arsenic is typically more toxic to aquatic life than organic arsenic.

• 

### The model assumes that equilibrium is quickly attained within the wa ter body following discharge and is consistently maintained between the water column and surficial bed sediments. This assumption is especially significant regarding metal equilibrium within lakes and ponds. The model equations presented in Appendix C do

n ot take into consideration the effects of currents, inversion, or temperature variations within the water column, but assume that the entire mass of the lake or pond is at equilibrium. The model does not account for the accumulation of metal

concentrations in bottom sediments and pore water that occur over prolonged discharge periods.

• 

### The model assumes that metals dissolved or sorbed within the water column and bed sediments can be described by a partition coefficient.

• 

### The model assumes that metals sorbed to bed sediments are considered a net loss from the water body system. This assumes that bed sediments are not resuspended and deposited further downstream, but remain within the immediate discharge zone and do not further contribute to the dissolved or suspended sediment concentrations within the water body.

• 

### The model does not take into account ambient background metal concentrations or contributions from other point and nonpoint sources.

• 

### The metal loadings included in the model are not representative of the total metal loadings from steam electric power plants. There are several waste streams that are not included in the analysis (e.g., stormwater runoff, metal cleaning wastes, coal pile runoff).

C-21Appendix D

— Wildlife Model Methodology



# APPENDIX D

WILDLIFE MODEL METHO DOLOGY

This appendix presents the model equations, input values and pollutant benchmarks, and methodology limitations/assumptions for the wildlife model. Wildlife impacts include the following ecological receptors:

• Aquatic and sediment organisms (amphibians, fish, invertebrates) in direct contact with receiving water and/or sediment in the immediate discharge zone of steam electric power plants; and

• Wildlife (eagles and minks) 9 

### that consume fish from receiving waters in the immediate discharge zone of steam electric power plants.

For the b aseline conditions and five regulatory options (Options 1, 2, 3, 4, and 5), the

U.S. Environmental Protection Agency (EPA) estimated pollutant concentrations in the receiving water and sediment using the water quality model ( Appendix C ). The wildlife model uses these concentrations as inputs.

Model input requirements for the equations presented in A ppendix D can be divided into five major categories: (1) input variable described by another equation; (2) site

- specific input value (e.g., pollutant concentration from the water quality model); (3) default model assumption value (e.g., 15 percent of total mercury is dissolved in the water column as methylmercury); (4) pollutant

- specific value; and (5) receptor

- specific benchmark. The following tables in

A

ppendix D describe the input requirements and data sources used in the wildlife model:

• Table D-1 . Chemical Stressor Concentration Limits (CSCLs) for Sediment Biota;

• Table D-2

. Bioconcentration Factors ( BCFs) for Trophic Level 3 (T3) and Trophic Level 4 (T4) Fish; and

• Table D-3 . No Effect Hazard Concentration (NEHC) Benchm arks for Minks and Bald Eagles.

Wildlife Model Equations

EPA calculated the hazard quotient (HQ) (i.e., comparison of wildlife model va lue to benchmark) for aquatic organisms in direct contact with metals in the sediment and ingestion of contaminated fish for piscivorous wildlife (HQ sed 

### and HQ I 

### ). An HQ of higher than one (i.e., pollutant concentration exceeds benchmark) indicates a potent ial impact to aquatic organisms or wildlife (i.e., minks or eagles). To calculate HQ I 

### , EPA estimated the metal concentration in fish (C fishT 

### ) for trophic level 3 and trophic level 4 fish. EPA used the equations presented below to calculate HQ values and fish tissue concentrations for arsenic, cadmium, chromium (VI), copper, lead, mercury (as methylmercury), nickel, selenium, thallium, and zinc.

9 EPA selected eagles and minks to represent national

- scale impacts from steam electric power plants because their habitats cover the entire United States (i.e., can be used for a national assessment).



### D-1Appendix D

— Wildlife Model Methodology



### Impact to Aquatic Life Receptors from Direct Contact with Sediment . Below is the equation for calculating the potential negative impact to aquatic organisms from direct contact with the sediment in receiving water bodies.

EQUATION D-1
C bs



### = HQ sed 

### CSCL sed 

### where:

HQ sed 

### = Hazard quotient for contact with sediment Output from Equation D

- 1

C bs 

### = Total pollutant concentration in sediment (milligrams per liter [mg/L]) Water quality model output Equation C

- 5

CSCL sed 

### = Ecological benchmark for sediment (milligrams per kilograms [mg/kg]) Receptor

- specific

benchmark (see Table D

- 1 )

Assessment of Pollutant Bioconcentration in Fish. Equation D-2 calculates pollutant concentrations in fish for the evaluated pollutants, except for mercury. Because the more toxic form of mercury is methylmercury, EPA used Equation D-3 for this pollutant [U.S. EPA, 2005b]. Equation D-3 estimates the concentration of methylmercury in fish tissue, as opposed to total mercury.

EQUATION D-2

C fishT 

### = C

wc 

### × BCF T



### EQUATION D-3

C fishT 

### = ( 0.15 × C dw 

### ) × BCF T 

### where:

C fishT 

### = Pollutant concentration in fish, where T represents trophic level T3 or T4 (mg/kg) Output from Equation D

- 2

or Equation D

- 3

C

wc 

### = Total pollutant concentration in water (mg/L) Water quality model output Equation C

- 3

C dw 

### = Dissolved pollutant concentration in water (mg/L) Water quality model output Equation C

- 4

0.15 = Fraction of total mercury as dissolved methylmercury (unitless) Assumed value [U.S. EPA, 2005b]

BCF T 

### = Bioconcentration factor for specified trop hic level (liters per kilogram [L/kg]) Trophic

- level

- specific and pollutant

- specific value (see Table D

- 2 )

Adverse Effects to Piscivorous Wildlife . To calculate the hazard to piscivorous wildlife (i.e., wildlife that consume fish), EPA used the following equation to calculate the potential for

D-2Appendix D

— Wildlife Model Methodology



### adverse effects to minks consuming trophic level 3 fish and eagles consuming trophic level 4

fish:

EQUATION D-4
C fishT 

### HQ I 

### = NEHC where:

HQ I 

### = Hazard quotient for ingestion of fish Output from Equation D

- 4

C fishT 

### = Concentration of pollutant in fish (mg/kg or micrograms per grams [μg/g]) for a specified trophic level (T3 or T4) Output from Equation D-2

or Equation D-3

NEHC = No effect hazard concentration (μg/g) Receptor

- a nd pollutant

specific (see Table D

- 3 )

Wildlife Model Inputs

Table D-1 . CSCLs for Sediment Biota

Pollutant in Wildlife Impact Assessment CSCL Benchmark Value (mg/kg) Notes (Source)

Arsenic 10.798 (EPA 905

- R96

- 008)

Cadmium 0.583 (EPA 905

- R96

- 008)

Chromium VI 36.286 No benchmark for chromium VI. EPA used the total chromium benchmark, which may underestimate the impact to wildlife (EPA 905

- R96

- 008). Copper 28.012 (EPA 905

- R96

- 008)

Lead 37 (EPA 905

- R96

- 008) Mercury 0.174 (Arch ET&C 2000)

Nickel 19.514 (EPA 905

- R96

- 008)

Selenium None identified EPA could not complete the analysis for this pollutant

– no benchmark for comparison. Thallium None identified Zinc, total 98 (EPA 905

- R96

- 008)
Source: NOAA, 2008.



### Table D-2. BCFs for Trophic Level 3 and 4 Fish

Pollutant BCF Value for Trophic Level 3 (T3) Fish (L/kg) BCF Value for Trophic Level 4 (T4) Fish Value (L/ kg) Comment Source

Arsenic total 4.00E+00 4.00E+00 Barrows, et al., 1980

Cadmium 2.70E+02 2.70E+02 Kumada et al., 1972

Chromium VI 6.00E

- 01 6.00E

- 01 Stephan, 1993

Copper 0.00E+00 0.00E+00 T4 filet value used for T3 Stephan, 1993

Lead 4.60E+01 4.60E +01 Stephan, 1993

Mercury 1.60E+06 6.80E+06 U.S. EPA, 1997a

Nickel 0.8 0.8 Soluble salts Stephan, 1993



### D-3Appendix D

— Wildlife Model Methodology



### Table D-2. BCFs for Trophic Level 3 and 4 Fish

Pollutant BCF Value for Trophic Level 3 (T3) Fish (L/kg) BCF Value for Trophic Level 4 (T4) Fish Value (L/ kg) Comment Source

Selenium 4.90E+02 1.70E+03 Lemly, 1985a

Thallium 3.40E+01 1.30E+02 Barrows et al., 1980 and Stephan, 1993

Zinc 3.50E+02 3.50E+02 Murphy et al., 1978



### Table D-3 . NEHC Values for Mink and Bald Eagles

Pollutant in Wildlife

ImpactAssessment NEHC Benchmark

Value for Mink (T3 Fish)

(μg/g) NEHC Benchmark Value for Eagle (T4 Fish )

(μg/g) Notes Arsenic, total 7.65 22.4 Cadmium, total 5.66 14.7

Chromium VI 17.7 26.6 No benchmark for chromium VI. EPA used the total chromium benchmark, which may underestimate the impact to

wildlife. Copper, total 41.2 40.5 Lead, total 34.6 16. 3 Methylmercury 0.37 0.5 No benchmark for methylmercury. EPA used the total mercury benchmark, which may underestimate the impact to wildlife. Nickel, total 12.5 67.1 Selenium, total 1.13 4 Thallium, total None identified None identified EPA could n ot complete the analysis for this pollutant

– no benchmark for comparison. Zinc, total 904 145
Source: USGS, 2008.



### Wildlife Model Methodology Limitations and Assumptions

EPA was required to make assumptions about various inputs, resulting in limitations with respect to model output and interpretation. Variability occurs from heterogeneous characteristics, such as body weight differences within a population or the contaminant levels in the environment. Uncertainty represents a lack of knowledge about factors such as the adverse effects from exposure to pollutants. The assumptions and limitations of the wildlife model include the following:

• 

### Additive Risks Across Pathways. The wildlife model described above does not consider additive risks across pathways. For example, the modeled impacts to wildlife from ingesting contaminated fish does not consider the risk from direct contact with surface water. The receptors chosen for the wildlife ingestion model, mink and eagle, do not spend large amounts of time in co ntact with the surface water; therefore, not including the impact of direct contact with surface water should only minimally

D-4Appendix D

— Wildlife Model Methodology



### underestimate the impacts. In addition, the wildlife model does not consider the impact from water ingestion. Because many of the p ollutants considered in this analysis are bioaccumulative in nature, the model considers only ingestion of the food source since it is likely the dose from the food source dominates the dose from water ingestion.

• 

### Receptor Populations Evaluated. EPA conside red the limitations and made multiple assumptions in choosing receptor populations to evaluate. First, EPA assumed that, because this is a national model, the receptor species and receiving water occur together (i.e., all receiving waters are habitat for the receptor species even though that may not always be the case). In addition, due to the scope of the project, EPA considered a limited number of species for use as receptors. For the assessment of the impacts to aquatic life, EPA chose to use the sedimen t CSCL values from its Assessment and Remediation of Contaminated Sediments (ARCS) Program

Guidelines where available. The ARCS Program Guidelines did not include a mercury CSCL; therefore, EPA chose to use the benchmark from Canada’s Interim Sediment Qual ity Guidelines (ISQGs) [NOAA, 2008]. For the wildlife receptors, EPA chose minks and eagles due to their national distribution and data available to conduct the analysis [USGS, 2008]. By choosing a limited number of species, the model inherently excludes t he impacts to critical assessment endpoints such as threatened and endangered species. EPA attempts to address this limitation in the impact assessment by presenting a proximity analysis of steam electric power plants to habitats of threatened and endangered species (see Section 3.4.3 of this report).

• 

### Bioavailability and Speciation of Pollutants. Each model assumes that all forms of a pollutant are equally bioavailable to ecological receptors. Therefore, data inputs for

the wildlife model include total met al in the water column (i.e., dissolved plus particles sorbed to suspended sediment) or sediment concentration for all pollutants analyzed, except where noted. In addition, some pollutant forms are more toxic to organisms, such as various forms of arsenic. While different forms of arsenic exist in the water column, it is not possible to determine the percentages of each due to the complexities of the chemistry of a particular water body. Because of bioavailability and metal speciation assumptions made for the wildlife impact assessment, the impact to receptors may be over

- or underestimated.

• 

### Indirect Ecological Effects. The wildlife model does not consider indirect ecological effects, such as depletion of food sources. Such indirect effects are difficult to assess and are thought to have minimal impact on some wildlife species because the impacted receiving water is only a small portion of the species’ habitat. In addition, many species will move into other areas in search of prey if food sources in their

cur rent habitat decline.

• 

### Full Mixing Effects for Receiving Water. The water quality model assumes that the receiving water body is fully mixed. In reality, the water in lakes might stratify, especially if they are deep enough. Chemical speciation, mostly bas ed on pH, varies by strata; for example, if the hypolimnion (i.e., lowest stratum of a lake) has a much lower pH than the epilimnion (i.e., upper stratum), the concentration or speciation of many metals may vary between the two layers. Therefore, bottom -dw elling organisms

D-5Appendix D

— Wildlife Model Methodology



### would be exposed to different species and concentrations of metals. Due to the complexity of these relationships and necessity for site

- specific data, none of the impact analyses considered stratification of receiving waters.

• 

### Multiple Pol lutant Exposures. According to EPA’s Steam Electric Power Generating Point Source Category: Final Detailed Study Report [U.S. EPA, 2009b]

, receptors will be exposed to multiple constituents simultaneously. However, the wildlife model examines the impact of individual pollutants to receptors and does not take into account how the interaction of multiple pollutants impacts the adverse effects to receptors. For example, EPA did not consider the impact of mercury on the uptake or toxicity of selenium. There is evidence in the literature that these two compounds interact with each other in the environment and may decrease the level of impact on a receptor; conversely, the interaction of other pollutants may increase the impact to a receptor. However, because benchmarks are based on the toxicity of individual chemicals, and the relationships between chemicals are complex, it is beyond the scope of this analysis to include the effects of multiple pollutant interactions on receptors.

• 

### Ecological Benchmarks. EPA used ecological benchmarks as described above to determine impacts to aquatic organisms from direct contact with contaminated sediment. The benchmarks represent the threshold effect level (TEL) for H azteca. 10


### If an organism ingests chemical concentration above the TEL, some effect (or response) will be produced. If the concentration ingested is below the TEL, no effect (or response) will occur. The TEL represents the concentration of a chemical that would result in “no effect,” therefore the results presented in EA report are a more environmentally protective impact estimate [USGS, 2008].

10 The m ercury CSCL does not specify the aquatic organism [NOAA, 2008].



### D-6Appendix E

—

Human Health Model Methodology



# APPENDIX E

HUMAN HEALTH MODEL M ETHODOLOGY

This appendix presents the model equations, input values and benchmarks, and methodology limitations/assumptions for the human health model. H uman health impacts include the following receptor groups:

• Child cohorts (recreational) that consume fish exposed to pollutants as a result of discharges from steam electric power plants;

• Child cohorts (subsistence) that consume fish exposed to pollutants as a result of discharges from steam electric power plants;

• Adult cohorts (recreational) that consume fish exposed to pollutants as a result of discharges from steam electric power plants; and

• Adult cohorts (subsistence) that consume fish exposed to pollu tants as a result of discharges from steam electric power plants.

For the baseline conditions and five regulatory options (Options 1, 2, 3, 4, and 5), the

U.S. Environmental Protection Agency (EPA) estimated pollutant concentrations in fish tissue using t he wildlife model ( A ppendix D). The human health model uses these concentrations as inputs.

Model input requirements for the equations presented in Appendix E can be divided into five major categories: (1) input variable described by another equation; (2) site

- specific input value (i.e., pollutant concentration in fish tissue); (3) default model assumption value (e.g., fraction of trophic level 3 [T3] and trophic level 4 [T4] fish intake by receptor); (4) receptor

cohort

- specific value (e.g., body weight [B W] and fish consumption rate); and (5) pollutant

specific value (i.e., reference dose [RfD] for noncancer effects and cancer slope factor, CSF). The following tables in Appendix E describe the input requirements and data sources used in the

human health mo del:

• Tab le E-1 . Calculation of F T3 

### and F T4



### .

• Table E-2 . Default Input Values for the Human Health Model;

• Table E-3

. Receptor Cohort

- Specific input Values for the H uman Health Model ; and

• Table E-4 . Reference Doses and Cancer Slope Factors for Pollutants in t he Human

Health Model.

Human Health Model Equations

EPA calculated the hazard quotient (HQ) (i.e., comparison of human health model value to benchmark) for ingestion of contaminated fish by multiple cohorts. An HQ of higher than one (i.e., pollutant dosag e or cancer risk factor exceeds benchmark) indicates a potential impact to

the human cohort. To calculate the HQ, EPA estimated the metal concentrations in fish fillets consumed by humans (i.e., dose), using an assumed consumption ratio of T3 and T4 fish a nd

E-1Appendix E

—

Human Health Model Methodology



### pollutant concentrations in fish . EPA also calculated a lifetime excess cancer risk (LECR) for each cohort. This study used 1

- in

- 1,000,000 cancer risk as an acceptable risk threshold when evaluating exposures associated with fish consumption. EPA used the equations presented below to calculate HQ values (noncancer impact) for arsenic, cadmium, chromium (VI), copper, lead, mercury, nickel, selenium, thallium, and zinc and LECR values for arsenic.

EQUATION E-1

C fish_fille t 

### = F T3 

### × C fishT3F 

### + F T4 

### × C fishT4F 

### where:

C fish_fillet 

### = Average fish fillet concentration ingested by humans (milligrams per kilograms [mg/kg]) Output from Equation E-1

C fishT3F 

### = Concentration of contaminant in fish at trophic level 3 (mg /kg) Wildlife model output Equation D-2 and Equation

D

- 3

C fishT4F 

### = Concentration of contaminant in fish at trophic level 4 (mg/kg) Wildlife model output Equation D-2 and Equation

D

- 3

F T3 

### = Fraction of trophic level 3 fish intake (unitless) Assumed value of 0.36 (see calculation below)

F T4 

### = Fraction of trophic level 4 fish intake (unitless) Assumed value of 0.64 (see calculation below )

Calculation of F T3 

### and F T4



### To determine the fraction of T3 and T4 fish intake for humans, EPA started with the data presented in the 2011 Emissions Factor Handbook, Table 10

- 74 [U.S. EPA, 2011b]. EPA then completed the following analysis:

1. Assigned trophic levels to fish if not already listed in the table.

2. Sum the quantities of fish consumed by trophic level.

3. Determine f raction of fish consumed at each trophic level.

Tab le E-1 documents the data and analysis performed. EPA chose to use the factors for fish intake that corresponded to rivers and streams; this is the most common receiving water source

in the EA model.

E-2Appendix E

—

Human Health Model Methodology



### Tab le E-1. Calculation of F T3 

### and F T4

Species Trophic

Level Ice Fishing Lakes and Ponds Rivers and Streams

Quantity

Consumed Grams (x10 3 )

Consumed Quantity

Consumed Grams (x10 3 )

Consu med Quantity

Consumed Grams (x10 3 )

Consumed

Landlocked

salmon 4 832 290 928 340 305 120

Atlantic salmon 4 3 1.1 33 9.9 17 11 Togue (Lake trout) 4 483 200 459 160 33 2.7

Brook trout 4 1,309 100 3,294 210 10,185 420

Brown trout 4 275 54 375 56 338 23

Yellow perch 3 235 9.1 1,649 52 188 7.4

White perch 3 2,544 160 6,540 380 3,013 180

Bass (smallmouth and largemouth) 4 474 120 73 5.9 787 130

Pickerel 3 1,091 180 553 91 303 45

Lake whitefish 3 111 20 558 13 55 2.7 Hornpout (Catfish and

bullhea ds) 3 47 8.2 1,291 100 180 7.8

Bottom fish (Suckers, carp and sturgeon) 3 50 81 62 22 100 6.7

Chub 3 0 0 252 35 219 130

Smelt 3 7,808 150 428 4.9 4,269 37

Other 4 201 210 90 110 54 45

TOTALS 15,463 1,583 16,587 1,590 20,046 1,168

Totals by Trop hic Level:

T3

Total 11,886 608 11,333 698 8,327 417

T4

Total 3376 765.1 5162 781.8 11665 751.7

Calculation of Factors by Trophic Level

T3

Factor 0.77 0.38 0.68 0.44 0.42 0.36

T4

Factor 0.22 0.48 0.31 0.49 0.58 0.64
Source: U.S. EPA, 2011b.

Bold i ndicates factors selected for the human health model.



### The next equation calculates the daily intake of contaminant from fish ingestion, also called the average daily dose (ADD). Based on the ADD, the human health model calculates the lifetime average dail y dose (LADD) in Equation E-3.

E-3Appendix E

—

Human Health Model Methodology



### EQUATION E-2
C fish_fillet 

### × CR fish 

### × F fish 

### ADD = 1,000 × BW

where:

ADD = Daily dose of pollutant from fish ingestion (mg/kg BW/day) Output from Equation E-2

C fish_fillet 

### = Avera ge fish fillet concentration ingested by humans (mg/kg) 11 

### Output from Equation E-1

CR fish 

### = Consumption rate of fish (g ww/day) Age

- cohort

- specific

assumed value (see Table E

- 3 )

F fish 

### = Fraction of fish intake from contaminated

source Assumed value of 1

1,000 = Conversion factor (grams per kilograms [g/kg])

BW = Body weight (kg) Age

- cohort

- specific

assumed value (see Table E

- 3 )

EQUATION E-3

LADD = ADD × ED × EF

AT × 365 where:

LADD = Lifetime average daily dose (mg /kg BW/day) Output from Equation E

- 3

ADD = Daily dose of pollutant from fish ingestion (mg/kg BW/day) Output from Equation E-2

ED = Exposure duration for oral ingestion (yr) 12 

### Age

- cohort

- specific

assumed value (see Table E

- 3 )

EF = Exposure frequency (d ays/yr) Assumed value of 350 13

11 Based on literature review (including EPA and Agency for Toxic Substances and Disease Registry ( ATSDR ) references), arsenic in fish is mostly in the organic form and not harmful to humans. T he inorganic form of arsenic is harmful to humans; EPA’s 1997 document, Arsenic and Fish Consumption

, reported the inorganic arsenic concentration in fish is between 0.4 – 4 percent of the total arsenic accumulating in fish. EPA estimated the inorganic ars enic concentration in fish by assuming 4 percent of the total arsenic is inorganic. EPA used the inorganic arsenic concentration in fish to determine human health impacts. The human health model multiplies the Cfish_fillet concentration by 4 percent for arsenic (converting concentration from total to inorganic).

12 The model calculates the LADD of arsenic for each child cohort ( six recreational and six subsistence) and for each adult cohort ( one recreational and one subsistence). EPA assumed the exposure dur ations (ED) for use in the LADD calculation is equal to the length of time in that cohort range. Therefore the exposure duration for the six

- child cohorts (youngest to oldest) are 1, 1, 3, 5, 5, and 5 years, respectively. For the adult cohort, the exposure duration is 49 years.

13 Exposure frequency was set to 350 days per year, assuming residents take an average of two weeks of vacation away from their homes each year.



### E-4Appendix E

—

Human Health Model Methodology



### AT = Averaging time (yr) Assumed value of 70 [U.S. EPA, 2011b ]

365 = Conversion factor (days/yr)

Calculated Impacts from Noncarcinogenic Pollutants

EQUATION E-4
ADD HQ = RfD where:

HQ = Hazard quotient Output from Equation E

- 4

ADD = Daily dose of pollutant from fish ingestion (mg/kg BW/day) Output from Equation E-2

RfD = Noncancer reference dose (mg/kg BW/day) Chemical

- specific value (see Table E

- 4 )

Calculated Risk from Carcinogeni c Pollutants

The risk from cancer

- causing pollutants is expressed in terms of lifetime excess cancer risk (LECR).

EQUATION E-5

LECR = LADD × CSF

where:

LECR = Lifetime excess cancer risk Output from Equation E

- 5

LADD = Lifetime average daily dose (mg/kg BW/d) Output from Equation E

- 3

CSF = Cancer slope factor (mg/kg BW/day) -1 

### Chemical

- specific assumed

value (see Table E

- 4 )

Human Health Model Inputs

Table E-2 . Default Input Values for the Human Health Model

Input

Variable Description Default Value Data Source

F T3 Fraction of trophic level 3 fish intake 0.36 U.S. EPA, 2011b

F T4 Fraction of trophic level 4 fish intake 0.64 U.S. EPA, 2011b

F f

ish Fraction of fish intake from contaminated

source 1 Assumed value.

EF Exposure frequency (days/yr) 350 Assumed value.



### E-5Appendix E

—

Human Health Model Methodology



### Table E-2 . Default Input Values for the Human Health Model

Input

Variable Description Default Value Data Source

AT Averaging time (yr) 70 U.S. EPA, 2011b



### Table E-3 . Rece ptor- Cohort

- Specific Input Values for the Human Health Model

Receptor Cohort a Body Weight (kg) a Consumption Rate (g/day) b Exposure Duration (years)

Child Recreational

Fisher 1 to <2 years 11.4 2.5 (b) 1 2 to <3 years 13.8 3 (b) 1 3 to <6 years 18. 6 3.5 (b) 3 6 to <11 years 31.8 5.1 (b) 5 11 to <16 years 56.8 5.7 (b) 5 16 to <21 years 71.6 7.2 (b) 5

Child Subsistence

Fisher 1 to <2 years 11.4 13.7 (b) 1 2 to <3 years 13.8 16.6 (b) 1 3 to <6 years 18.6 26 (b) 3 6 to <11 years 31.8 35 (b) 5 11 to <16 years 56.8 39.8 (b) 5 16 to <21 years 71.6 50.1 (b) 5

Adult Recreational Fisher 80 20 (c) 49

Adult Subsistence Fisher 80 88 (d) 49
Acronyms: g/day (grams per day); kg (kilograms).

a – The child cohort age ranges correspond to the ranges provided in the 2008 Child

- Specific Exposure Factor Handbook (EFH) for body weights [U.S. EPA, 2008a].

b – EPA determined consumption rates for child cohorts using data from Table 10

- 1 (Recommend Per Capita and Consumer

Only Values for Fish Intake) for fi nfish consumption [U.S. EPA, 2011b]. EPA used the mean values for recreational fishers and 95th percentile values for subsistence fishers. EPA converted the listed consumption rate (g/kg

- day) to g/day by multiplying by mean body weight for each cohort as l isted in U.S. EPA, 2008 [ERG, 2013m]. Fish intake rates provided in the reference [U.S. EPA, 2011b] are recommended for the general population; the selection of consumption rates for exposure assessment purposes may vary depending on the exposure scenarios being evaluated.

c – EPA determined consumption rates for adult recreational fishers using data from Table 10

- 5 of U.S. EPA, 2011b. EPA used the mean values for freshwater fish consumption (g/day) based on location and population groups. EPA used consumpt ion rates for all respondents and calculated a median value to use in the model [ERG, 2013m]. U.S. EPA, 2011b does not provide recommended values for fish consumption, but does present available data for certain geographic areas. Assessors may use thes e da ta, if appropriate, to the scenarios and populations being assessed. EPA used the mean consumption rate across the geogprahic areas to represent a central

- tendency value for adult fishers across the United States. A fraction of the adult fisher population may experience higher consumption rates as evidenced by the 95 th percentile values presented in Table 10 -5.

d – EPA determined consumption rates for adult subsistence fishers using data from Table 10

- 6 of U.S. EPA, 2011b. EPA used

the mean values for fish consumption based on location/name of Native American tribe. EPA used values listed for adults and converted the data into consumption rates (units of g/day) assuming an adult body weight of 80 kg, as provided in Section 8.1 of

U.S. EPA, 2011b. EPA then calculated a median value to use in the model [ERG, 2013m]. U.S. EPA, 2011b does not provide recommended values for fish consumption but does present available data for certain geographic areas. Assessors may use these data, if appropriate, to the scenarios and populations being assessed. EPA used the mean consumption rate across the geogprahic areas to represent a central

- tendency value for adult fishers across the United States. A fraction of the adult fisher population may experience higher consumption rat es as evidenced by the 95 th percentile values presented in Table 10 -6.



### E-6Appendix E

—

Human Health Model Methodology



### Table E-4 . RfDs and Cancer Slope Factors (CSF) for Pollutants in the Human Health

Model

Pollutant in Human Healt h Impact Assessment RfD (mg/kg

- day) CSF (mg/kg

- day) -1 Notes a Arsenic, inorganic 3.00E

- 04 1.50E+00 RfD and CSF for drinking water ingestion

Cadmium, total 1.00E

- 03 RfD for food consumption

Chromium VI 3.00E

- 03 RfD for drinking water ingestion

C opper 1.00E

- 02 Used the intermediate oral minimal risk level (MRL) as the reference dose [ATSDR, 2010a] Lead, total None available
Methylmercury 1.00E

- 04 RfD for fish consumption only

Nickel, total 2.00E

- 02 RfD for soluble salts; used for food consumption Selenium, total 5.00E

- 03 RfD for food consumption

Thallium, total 1.00E

- 05 Used value cited in U.S. EPA, 2010 for thallium chloride as the reference dose; used for chronic oral exposure Zinc, total 3.00E

- 01 RfD for food consumption

a – References include ATSDR, 2010 for copper; U.S. EPA, 2010 for thallium, and U.S. EPA, 2011c for all other pollutants.



### Human Health Model Limitations and Assumptions

The human health model limitations and assumptions include the following:

• 

### Additive Ris ks Across Pathways. The human health model does not consider additive risks across pathways. For example, the model assumes that the human population consuming the fish is not also ingesting contaminated drinking water. Exposures from fish consumption and drinking water are likely to occur over different time frames (because of ground water travel) and may involve different receptors (e.g., a resident near a receiving water exposed to ground water contamination may not be a recreational fisher). Similarly, the model assumes that these populations are not coming in direct contact with contaminated surface water or sediment through recreation. Based on these assumptions, the model may underestimate total risk to

human health from combustion wastewater.

• 

### Bioava ilability and Speciation of Pollutants. The assumptions listed for the wildlife

model in A ppendix D apply to pollutant concentrations modeled in fish and therefore impact the human health impact assessment.

• 

### Full Mixing Effects for Receiving Water. The ass umptions listed for the wildlife

model in Appendix D apply to pollutant concentrations modeled in fish and therefore impact the human health impact assessment.

• 

### Multiple Pollutant Exposures. According to previous analyses and literature reviewed [U.S. EPA, 2009b], people who ingest fish from impacted waters will be exposed to multiple pollutants from the waste streams evaluated. However, the model evaluates each pollutant individually. Such an approach does not account for

E-7Appendix E

—

Human Health Model Methodology



### interactive effects that might be associated with exposures to mixtures. For example, some pollutants may have a higher risk when consumed together because of their interaction, whereas other pollutants may have less impact on human health when consumed together. Due to the complexity of these interactions and because benchmarks are based on the toxicity of individual chemicals, it is not possible to examine these synergistic effects in this analysis. Based on this limitation, risks of pollutants may be over

- or underestimated.

• 

### Human Expos ure Factors. Individual exposure factors, such as ingestion rate, body weight, and exposure duration, are variable due to the physical characteristics, activities, and behavior of the individual. EPA used the most current data regarding exposure assumption s, and these values represent EPA’s current guidance on exposure data [U.S. EPA, 2008a; U.S. EPA, 2011b].

• 

### Human Health Benchmarks. Uncertainties generally associated with human health

benchmarks are discussed in detail in EPA’s Guidelines for Carcinogen R isk

Assessment [U.S. EPA, 2005c] and Integrated Risk Information System (IRIS) [U.S. EPA, 2011c]. IRIS defines the RfD as “a n estimate (with uncertainty spanning perhaps an order of magnitude) of a daily oral exposure to the human population (including sen sitive subgroups) that is likely to be without an appreciable threat of deleterious effects during a lifetime.” RfDs are typically based on an assumption of lifetime exposure and may not be appropriate when applied to less

- than

- lifetime exposure situations [U.S. EPA, 2011c]. The cancer slope factor is an estimate of the human cancer risk per milligram of chemical per kilogram body weight per day. To calculate the lifetime average daily dose (LADD) used for the cancer impact assessment, EPA used the time in the cohort group (i.e., 1, 3, or 5 years depending on child cohort and 49 years for adult cohort) as the exposure duration (ED). The ED is the length of time exposure occurs at the concentration. This analysis may over

- or under- estimate the cancer risk if exposure is shorter than or longer than the ED, respectively. LADDs are appropriate when developing screening

- level estimates; however, EPA recommends calculating that risk by integrating exposures or risks through all life stages (e.g. chronic exposure for a child may occur across cohorts) [U.S. EPA, 2011b].

E-8Appendix F

—

Additional Model Results



# APPENDIX F

ADDITIONAL MODEL RES ULTS

Table F-1 . Number and Percentage of Immediate Receiving Waters that Exceeded a Criterion by Pollutant and Criteria Type at Baseline Pollutant Loadings

Pollutant Number of Immediate Receiving Waters that Exceeded a Criterion a

Freshwater

Acute NRWQC Freshwater

Chronic NRWQC Human

Health

Water and Organism NRWQC Human

Health Organism Only NRWQC Drinki ng Water

MCL Total Receiving Waters b

Number Exceeding Percentage Exceeding

Dissolved

Arsenic 6 7

- - - 7 2%

Total Arsenic

- - 147 96 19 147 49%

Dissolved

Cadmium 30 65

- - - 65 22%

Total

Cadmium - - - - 22 22 7%

Dissolved

Chromium VI 7 8

- - - 8 3%

Total

Chromium VI - - - - 2 2 1%

Dissolved Copper 18 21

- - - 21 7%

Total Copper

- - 1

- 1 1 <1%

Dissolved

Lead 9 31

- - - 31 10%

Total Lead

- - - - 16 16 5%

Dissolved Mercury 2 2

- - - 2 <1%

Total Mercury

- - - - 0 0 0%

Dissolved

Nickel 8 24

- - - 24 8%

Total Nickel

- - 7 0

- 7 2%

Total

Selenium - 42 13 0 20 42 14%

Total Thallium

- - 82 74 55 82 28%

Dissolved Zinc 16 16

- - - 16 5%

Total Zinc

- - 1 0

- 1 <1%

Source: ERG, 2013h; ERG, 2013l.
Acronyms: MCL (Maximum Contaminant Level); NRWQ C (National Recommended Water Quality Criteria).

a – A total of 297 immediate receiving waters (261 rivers and streams; 36 lakes, ponds, and reservoirs) were included in the wate r quality model.

b – These values are the sum and percentage of rivers, stream s, lakes, ponds, and reservoirs impacted.



### F-1

### Figure F

- 1. Baseline Total Arsenic Concentration in the Immediate Receiving WaterNumber of Plant Receiving Waters 120

110

100

90

80

70

60

50

40

30

20

10

0



### Total Arsenic Concentration in Receiving Water (mg/L) Appendix F

—

Additional Model Results



### T able F-2 . Total Arsenic Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 8.21E

- 08 8.11E

- 08 8.12E

- 08 a 3.71E

- 08 0.00E+00 0.00E+00

25 th 1.71E

- 06 1.71E

- 06 1.71E

- 06 6.87E

- 07 0.00E+00 0.00E+00

50 th 1.72E

- 05 1.72E

- 05 1.72E

- 05 5.64E

- 06 4.82E

- 08 5.90E

- 08 b

75 th 5.86E

- 04 5.70E

- 04 5.70E

- 04 3.85E

- 04 2.88E

- 06 2.79E

- 06

95 th 1.70E

- 02 1.70E

- 02 1.70E

- 02 8.77E

- 03 4.22E

- 04 3.36E

- 04

Max 2.22E+00 2.22E+00 2.22E+00 2.22E+00 1.39E+00 1.39E+00

a – Total pollutant removals for Regulatory Option 2 are greater than Regulatory Option 1; however, for certain pollutants the reductions estimated under Regulatory Option 2 are slightly less those reported under Regulatory Option 1.

b– Under Regulatory Option 4, some plants that discharge both leachate and flue gas desulfurization (FGD) treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system ; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-2Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Cadmium Concentration in Receiving Water (mg/L) Figure F

- 2. Baseline Total Cadmium Concentration in the Immediate Receiving Water

Table F-3 . Total Cadmium Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 3.47E

- 08 2.12E

- 08 2.07E

- 08 1.01E

- 08 0.00E+00 0.00E+00

25 th 7.41E

- 07 4.51E

- 07 4.45E

- 07 2.57E

- 07 0.00E+00 0.00E+00

50 th 6.10E

- 06 4.49E

- 06 4.29E

- 06 2.16E

- 06 2.68E

- 08 4.23E

- 08 a

75 th 1.98E

- 04 9.35E

- 05 9.29E

- 05 5.71E

- 05 1.04E

- 06 1.51E

- 06 a

95 th 8.95E

- 03 4.56E

- 03 4.49E

- 03 2.42E

- 03 2.07E

- 04 1.98E

- 04

Max 2.77E

- 01 2.77E

- 01 2.77E

- 01 1.81E

- 01 1.81E

- 01 1.81E

- 01

a– Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4.

See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-3

### Figure F

- 3. Baseline Total Chromium VI Concentration in the Immediate Receiving WaterNumber of Plant Receiving Waters 120

110

100

90

80

70

60

50

40

30

20

10

0



### Total Chromium VI Concentration in Receiving Water (mg/L) Appendix F

—

Additional Model Results



### T able F-4 . Total Chromium VI Conc entration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

25 th 1.01E

- 07 1.01E

- 07 8.35E

- 08 5.75E

- 08 0.00E+00 0.00E+00

50 th 1.01E

- 06 1.01E

- 06 9.90E

- 07 3.97E

- 07 0.00E+00 0.00E+00

75 th 2.30E

- 05 2.30E

- 05 2.29E

- 05 6.89E

- 06 0.00E+00 0.00E+00

95 th 1.95E

- 03 1.95E

- 03 1.80E

- 03 7.05E

- 04 2.63E

- 06 1.98E

- 07

Max 4.00E

- 01 4.00E

- 01 4.00E

- 01 2.62E

- 01 2.62E

- 01 2.62E

- 01



### F-4Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Copper Concentration in Receiving Water (mg/L) Figure F

- 4. Baseline Total Copper Concentration in the Immediate Receiving Water

Table F-5 . Total Copper Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 5.71E

- 08 4.80E

- 08 4.98E

- 08 a 3.68E

- 08 0.00E+00 0.00E+00

25 th 1.91E

- 06 1.57E

- 06 1.58E

- 06 a 9.21E

- 07 0.00E+00 0.00E+00

50 th 1.66E

- 05 1.24E

- 05 1.25E

- 05 a 6.36E

- 06 2.87E

- 08 4.50E

- 08 b

75 th 3.26E

- 04 2.73E

- 04 2.90E

- 04 a 1.92E

- 04 1.87E

- 06 2.16E

- 06 b

95 th 1.99E

- 02 1.39E

- 02 1.39E

- 02 7.31E

- 03 1.70E

- 04 1.69E

- 04

Max 1.32E+00 1.32E+00 1.32E+00 8.61E

- 01 8.61E

- 01 8.61E

- 01

a – Total pollutant removals for Regulatory Option 2 are greater than Regulatory Option 1; however, for certain pollutants the reductions estimated under Regulatory Option 2 are slightly less those reported under Regulatory Option 1.

b– Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Optio n 4.

See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-5Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Lead Concentration in Receiving Water (mg/L) Figure F

- 5. Baseline Total Lead Concentration in the Immediate Receiving Water

Table F-6 . Total Lead Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 3.32E

- 08 3.00E

- 08 3.00E

- 08 2.03E

- 08 0.00E+00 0.00E+00

25 th 1.38E

- 06 1.08E

- 06 1.08E

- 06 5.61E

- 07 0.00E+00 0.00E+00

50 th 1.03E

- 05 9.51E

- 06 9.51E

- 06 5.72E

- 06 1.22E

- 08 2.19E

- 08 a

75 th 2.00E

- 04 1.88E

- 04 1.88E

- 04 9.40E

- 05 8.08E

- 07 1.08E

- 06 a

95 th 1.68E

- 02 1.68E

- 02 1.68E

- 02 7.72E

- 03 9.42E

- 05 1.07E

- 04 a

Max 9.04E

- 01 9.04E

- 01 9.04E

- 01 7.17E

- 01 5.91E

- 01 5.91E

- 01

a– Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4.

See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-6Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Mercury Concentration in Receiving Water (mg/L) Figure F

- 6. Baseline Total Mercury Concentration in the Immediate Receiving Water

Table F-7 . Total Mercury Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.01E

- 09 9.69E

- 10 9.69E

- 10 6.88E

- 10 0.00E+00 0.00E+00

25 th 3.60E

- 08 2.38E

- 08 2.08E

- 08 1.71E

- 08 0.00E+00 0.00E+00

50 th 2.61E

- 07 1.87E

- 07 1.63E

- 07 1.03E

- 07 6.33E

- 10 3.26E

- 10

75 th 2.67E

- 06 1.64E

- 06 1.64E

- 06 8.71E

- 07 1.45E

- 08 1.03E

- 08

95 th 5.50E

- 05 4.95E

- 05 4.95E

- 05 3.01E

- 05 3.84E

- 07 2.63E

- 07

Max 1.92E

- 03 1.41E

- 03 1.41E

- 03 4.02E

- 04 5.15E

- 05 5.15E

- 05



### F-7Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Nickel Concentration in Receiving Water (mg/L) Figure F

- 7. Baseline Total Nickel Concentration in the Immediate Receiving Water

Table F-8 . Total Nickel Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 2.40E

- 07 1.53E

- 07 9.76E

- 08 7.44E

- 08 0.00E+00 0.00E+00

25 th 5.80E

- 06 3.74E

- 06 3.28E

- 06 1.71E

- 06 0.00E+00 0.00E+00

50 th 6.46E

- 05 3.16E

- 05 2.85E

- 05 1.99E

- 05 6.33E

- 10 3.26E

- 10

75 th 2.11E

- 03 9.23E

- 04 8.99E

- 04 6.54E

- 04 1.45E

- 08 1.03E

- 08

95 th 9.98E

- 02 5.93E

- 02 5.93E

- 02 3.51E

- 02 3.84E

- 07 2.63E

- 07

Max 3.32E+00 3.32E+00 3.32E+00 3.32E+00 5.15E

- 05 5.15E

- 05



### F-8Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Selenium Concentration in Receiving Water (mg/L) Figure F

- 8. Baseline Total Selenium Concentration in the Immediate Receiving Water

Table F-9 . Total Selenium Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.00E

- 07 8.40E

- 08 7.68E

- 08 1.90E

- 08 0.00E+00 0.00E+00

25 th 3.54E

- 06 3.22E

- 06 1.40E

- 06 2.50E

- 07 0.00E+00 0.00E+00

50 th 3.40E

- 05 2.37E

- 05 1.05E

- 05 4.26E

- 06 8.44E

- 08 1.20E

- 07 a

75 th 7.96E

- 04 6.89E

- 04 4.12E

- 04 2.04E

- 04 4.67E

- 06 6.93E

- 06 a

95 th 1.02E

- 01 6.63E

- 02 1.38E

- 02 5.63E

- 03 1.69E

- 03 2.28E

- 03 a

Max 3.57E+00 3.57E+00 3.57E+00 3.57E+00 3.57E+00 3.57E+00

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a ch emical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-9Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Thallium Concentration in Receiving Water (mg/L) Figure F

- 9. Baseline Total Thallium Concentration in the Immediate Receiving Water

Table F-10 . Total Thallium Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.22E

- 07 1.22E

- 07 4.48E

- 08 3.27E

- 08 0.00E+00 0.00E+00

25 th 3.02E

- 06 2.87E

- 06 2.49E

- 06 1.08E

- 06 0.00E+00 0.00E+00

50 th 2.70E

- 05 2.68E

- 05 2.51E

- 05 1.31E

- 05 1.99E

- 08 2.66E

- 08 a

75 th 4.25E

- 04 3.96E

- 04 3.63E

- 04 1.83E

- 04 1.42E

- 06 1.25E

- 06

95 th 4.58E

- 02 4.58E

- 02 4.58E

- 02 2.38E

- 02 1.78E

- 04 1.33E

- 04

Max 2.37E+00 2.37E+00 2.37E+00 2.37E+00 1.06E+00 1.06E+00

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a ch emical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-10Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Zinc Concentration in Receiving Water (mg/L) Figure F

- 10. Baseline Total Zinc Concentration in the Immediate Receiving Water

Table F-11 . Total Zinc Concentration (mg/L) in the Immediate Receiving Water by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 4.13E

- 07 2.94E

- 07 1.57E

- 07 1.15E

- 07 0.00E+00 0.00E+00

25 th 9.27E

- 06 6.02E

- 06 4.44E

- 06 2.33E

- 06 0.00E+00 0.00E+00

50 th 6.76E

- 05 4.14E

- 05 3.98E

- 05 2.03E

- 05 7.74E

- 08 4.30E

- 07 a

75 th 2.67E

- 03 1.83E

- 03 1.27E

- 03 5.35E

- 04 4.44E

- 06 1.77E

- 05 a

95 th 1.37E

- 01 7.05E

- 02 6.86E

- 02 3.05E

- 02 7.41E

- 04 2.41E

- 03 a

Max 7.46E+00 7.46E+00 7.46E+00 7.46E+00 1.86E+00 1.86E+00

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a c hemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-11Appendix F

—

Additional Model Results

a – The wildlife model applies the same total arsenic bioconcentration factors (BCFs) for both trophic level 0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Arsenic Concentration in Fish Tissue (mg/kg) Figure F

- 11. Baseline Total Arsenic Concentration in Trophic

Level 3 and Trophic Level 4 Fish Tissue in the Immediate Receiving Water

3 (T3) and trophic level 4 (T4) fish (see Appendix D ). Therefore, the estimated concentrations presented

here are identical for both trophic levels.



### Table F-12 . Total Arsenic Concentration (mg/kg) in Fish Tissue (T3 & T4) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 3.28E

- 07 3.24E

- 07 3.25E

- 07 a 1.48E

- 07 0.00E+00 0.00E+00

25 th 6.84E

- 06 6.83E

- 06 6.83E

- 06 2.75E

- 06 0.00E+00 0.00E+00

50 th 6.88E

- 05 6.88E

- 05 6.88E

- 05 2.26E

- 05 1.93E

- 07 2.36E

- 07 b

75 th 2.34E

- 03 2.28E

- 03 2.28E

- 03 1.54E

- 03 1.15E

- 05 1.12E

- 05

95 th 6.79E

- 02 6.79E

- 02 6.79E

- 02 3.51E

- 02 1.69E

- 03 1.34E

- 03

Max 8.88E+00 8.88E+00 8.88E+00 8.88E+00 5.55E+00 5.55E+00

a – Total pollutant removals for Regulatory Option 2 are greater than Regulatory Option 1; however, for certain pollutants the reductions estimated under Regulatory Option 2 are slightly less those reported under Regulatory Option 1.

b

– Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a chemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regul atory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.

c – The wildlife model applies the same total arsenic BCFs for both T3 and T4 fish (see Appendix D ). Therefore, the estimated concentrations presented here are identical fo r both trophic levels.



### F-12Appendix F

—

Additional Model Results

a – The wildlife model applies the same total cadmium BCFs for both T3 and T4 fish (see Appendix D ). 0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Cadmium Concentration in Fish Tissue (mg/kg) Figure F

- 12. Baseline Total Cadmium Concentration in Trophic Level 3 and Trophic Level 4 Fish Tissue in the Immediate Receiving Water

Therefore, the estimated concentrations presented here are identical for both trophic levels.



### Table F-13 . Total Cad mium Concentration (mg/kg) in Fish Tissue (T3 & T4) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 9.37E

- 06 5.73E

- 06 5.59E

- 06 2.74E

- 06 0.00E+00 0.00E+00

25 th 2.00E

- 04 1.22E

- 04 1.20E

- 04 6.93E

- 05 0.00E+00 0.00E+00

50 th 1.65E

- 03 1.21E

- 03 1.16E

- 03 5.82E

- 04 7.24E

- 06 1.14E

- 05 a

75 th 5.34E

- 02 2.52E

- 02 2.51E

- 02 1.54E

- 02 2.80E

- 04 4.09E

- 04 a

95 th 2.42E+00 1.23E+00 1.21E+00 6.53E

- 01 5.59E

- 02 5.36E

- 02

Max 7.48E+01 7.48E+01 7.48E+01 4.89E+01 4.89E+01 4.89E+01

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a c hemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.

b

– The wildlife model applies the same total cadmium BCFs for both T3 and T4 fish (see Appendix

D ). Therefore, the estimated concentrations presented here are identical for both trophic levels.



### F-13Appendix F

—

Additional Model Results

a – The wildlife model applies the same total chromium VI BCFs for both T3 and T4 fish (see Appendix 0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Chromium VI Concentration in Fish Tissue (mg/kg) Figure F

- 13. Baseline Total Chromium VI Concentration in Trophic Level 3 and Trophic Level 4 Fish Tissue in the Immediate Receiving Water

D ). Therefore, the estimated concentrations presented here are identical for both trophic levels.



### Table F-14 . Total Chromium VI Concentration (mg/kg) in Fish Tissue (T3 & T4) by Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

25 th 4.35E

- 09 4.35E

- 09 4.35E

- 09 3.33E

- 09 0.00E+00 0.00E+00

50 th 3.14E

- 07 3.14E

- 07 2.50E

- 07 1.23E

- 07 0.00E+00 0.00E+00

75 th 6.03E

- 06 6.03E

- 06 6.03E

- 06 2.05E

- 06 0.00E+00 0.00E+00

95 th 8.44E

- 04 8.44E

- 04 6.32E

- 04 2.51E

- 04 1.32E

- 06 6.14E

- 08

Max 2.40E

- 01 2.40E

- 01 2.40E

- 01 1.57E

- 01 1.57E

- 01 1.57E

- 01

a – The wildlife model applies the same total chromium VI BCFs for both T3 and T4 fish (see Appendix D ). Therefore, the estimated concentrations presented here are identical for both trophic

levels.



### F-14Appendix F

—

Additional Model Results

a – The wildlife model applies the same total lead BCFs for both T3 and T4 fish (see Appendix D ). 0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Lead Concentration in Fish Tissue (mg/kg) Figure F

- 14. Baseline Total Lead Concentration in Trophic Level 3 and Trophic Level 4 Fish Tissue in the Immediate Receiving Water

Therefore, the estimated concentrations presented here are identical for both trophic levels.



### Table F-15 . Total Lead Concentration (mg/kg) in Fish Tissue (T3 & T4) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.53E

- 06 1.38E

- 06 1.38E

- 06 9.33E

- 07 0.00E+00 0.00E+00

25 th 6.37E

- 05 4.95E

- 05 4.95E

- 05 2.58E

- 05 0.00E+00 0.00E+00

50 th 4.75E

- 04 4.38E

- 04 4.38E

- 04 2.63E

- 04 5.62E

- 07 1.01E

- 06 a

75 th 9.19E

- 03 8.63E

- 03 8.63E

- 03 4.32E

- 03 3.72E

- 05 4.95E

- 05 a

95 th 7.72E

- 01 7.72E

- 01 7.72E

- 01 3.55E

- 01 4.33E

- 03 4.91E

- 03 a

Max 4.16E+01 4.16E+01 4.16E+01 3.30E+01 2.72E+01 2.72E+01

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a ch emical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.

b

– The wildlife model applies the same total lead BCFs for both T3 and T4 fish (see Appendix D ). Therefore, the estimated concentrations presented here are identical for both trophic levels.



### F-15Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Methylmercury Concentration in Fish Tissue (mg/kg) Figure F

- 15. Baseline Methylmercury Concentration in Trophic Level 3 Fish Tissue in the Immediate Receiving Water

Table F-16 . Methylmercury Concentration (mg/kg) in Fish Tissue (T3) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 2.43E

- 04 2.33E

- 04 2.33E

- 04 1.65E

- 04 0.00E+00 0.00E+00

25 th 8.65E

- 03 5.72E

- 03 4.98E

- 03 4.10E

- 03 0.00E+00 0.00E+00

50 th 6.26E

- 02 4.49E

- 02 3.91E

- 02 2.47E

- 02 1.52E

- 04 7.82E

- 05

75 th 6.41E

- 01 3.94E

- 01 3.94E

- 01 2.09E

- 01 3.49E

- 03 2.48E

- 03

95 th 1.32E+01 1.19E+01 1.19E+01 7.22E+00 9.22E

- 02 6.31E

- 02

Max a 4.62E+02 3.37E+02 3.37E+02 9.65E+01 1.24E+01 1.24E+01

a – EPA calculated methylmercury fish tissue concentrations using bioconcentration factors which do not fully account for the complexity of biogeochemical reactions that can occur within an aquatic environment and result in lower bioaccumulation rates of mercury in fish. For example, fish are known to bioaccumulate mercury at lower rate s when exposed to surface waters with high selenium concentrations. In addition, bioconcentration factors do not account for a maximum limit a fish could accumulate before a lethal concentration is reached. To address the outliers in mercury fish tissue

co ncentrations, EPA compared fish tissue concentrations to site

- specific data available in the national fish advisory database and established calibration factors to lower the outlier values. Fish tissue concentrations presented in the figure and table above represent the uncalibrated values calculated by the wildlife model. For further details on the methodology for selecting calibration factors see ERG

memorandum EA Model Validation and Calibration (DCN SE01986).



### F-16Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Methylmercury Concentration in Fish Tissue (mg/kg) Figure F

- 16. Baseline Methylmercury Concentration in Trophic Level 4 Fish Tissue in the Immediate Receiving Water

Table F-17 . Methylmercury Concentration (mg/kg) in Fish Tissue (T4) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.03E

- 03 9.88E

- 04 9.88E

- 04 7.01E

- 04 0.00E+00 0.00E+00

25 th 3.67E

- 02 2.43E

- 02 2.12E

- 02 1.74E

- 02 0.00E+00 0.00E+00

50 th 2.66E

- 01 1.91E

- 01 1.66E

- 01 1.05E

- 01 6.45E

- 04 3.32E

- 04

75 th 2.72E+00 1.67E+00 1.67E+00 8.89E

- 01 1.48E

- 02 1.05E

- 02

95 th 5.61E+01 5.05E+01 5.05E+01 3.07E+01 3.92E

- 01 2.68E

- 01

Max a 1.96E+03 1.43E+03 1.43E+03 4.10E+02 5.25E+01 5.25E+01

a – EPA calculated methylmercury fish tissue concentrations using bioconcentration factors which do not fully account for the complexity of biogeochemical reactions that can occur within an aquatic environment and result in lower bioaccumulation rates of mercury in fish. For example, fish are known to bioaccumulate mercury at lower rate s when exposed to surface waters with high selenium concentrations. In addition, bioconcentration factors do not account for a maximum limit a fish could accumulate before a lethal concentration is reached. To address the outliers in mercury fish tissue

co ncentrations, EPA compared fish tissue concentrations to site

- specific data available in the national fish advisory database and established calibration factors to lower the outlier values. Fish tissue concentrations presented in the figure and table above represent the uncalibrated values calculated by the wildlife model. For further details on the methodology for selecting calibration factors see ERG

memorandum EA Model Validation and Calibration (DCN SE 01986 ).



### F-17Appendix F

—

Additional Model Results

a – The wildlife model applies the same total nickel BCFs for both T3 and T4 fish (see Appendix D ). 0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Nickel Concentration in Fish Tissue (mg/kg) Figure F

- 17. Baseline Total Nickel Concentration in Trophic Level 3 and Trophic Level 4 Fish Tissue in the Immediate Receiving

Water

Therefore, the estimated concentrations presented here are identical for both trophic levels.



### Table F-18. Total Nickel Concentration (mg/kg) in Fish Tissue (T3 & T4) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.92E

- 07 1.23E

- 07 7.81E

- 08 5.95E

- 08 0.00E+00 0.00E+00

25 th 4.64E

- 06 2.99E

- 06 2.63E

- 06 1.37E

- 06 0.00E+00 0.00E+00

50 th 5.17E

- 05 2.53E

- 05 2.28E

- 05 1.59E

- 05 2.67E

- 08 4.81E

- 08 a

75 th 1.68E

- 03 7.39E

- 04 7.19E

- 04 5.23E

- 04 1.62E

- 06 2.99E

- 06 a

95 th 7.98E

- 02 4.74E

- 02 4.74E

- 02 2.81E

- 02 3.28E

- 04 3.34E

- 04 a

Max 2.66E+00 2.66E+00 2.66E+00 2.66E+00 6.10E

- 01 6.10E

- 01

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a c hemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.

b

– The wildlife model applies the same total nickel BCFs for both T3 and T4 fish (see Appendix D ). Therefore, the estimated concentrations presented here are identical for both trophic levels.



### F-18Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Selenium Concentration in Fish Tissue (mg/kg) Figure F

- 18. Baseline Total Selenium Concentration in Trophic Level 3 Fish Tissue in the Immediate Receiving Water

Table F-19 . Total Selenium Concentration (mg/kg) in Fish Tissue (T3) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 4.92E

- 05 4.11E

- 05 3.76E

- 05 9.31E

- 06 0.00E+00 0.00E+00

25 th 1.74E

- 03 1.58E

- 03 6.84E

- 04 1.22E

- 04 0.00E+00 0.00E+00

50 th 1.67E

- 02 1.16E

- 02 5.13E

- 03 2.09E

- 03 4.13E

- 05 5.88E

- 05 a

75 th 3.90E

- 01 3.38E

- 01 2.02E

- 01 1.00E

- 01 2.29E

- 03 3.40E

- 03 a

95 th 4.98E+01 3.25E+01 6.78E+00 2.76E+00 8.28E

- 01 1.12E+00 a

Max 1.75E+03 1.75E+03 1.75E+03 1.75E+03 1.75E+03 1.75E+03

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a c hemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-19Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Selenium Concentration in Fish Tissue (mg/kg) Figure F

- 19. Baseline Total Selenium Concentration in Trophic Level 4 Fish Tissue in the Immediate Receiving Water

Table F-20 . Total Selenium Concentration (mg/kg) in Fish Tissue (T4) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.71E

- 04 1.43E

- 04 1.30E

- 04 3.23E

- 05 0.00E+00 0.00E+00

25 th 6.02E

- 03 5.48E

- 03 2.37E

- 03 4.25E

- 04 0.00E+00 0.00E+00

50 th 5.78E

- 02 4.03E

- 02 1.78E

- 02 7.24E

- 03 1.43E

- 04 2.04E

- 04 a

75 th 1.35E+00 1.17E+00 7.00E

- 01 3.47E

- 01 7.94E

- 03 1.18E

- 02 a

95 th 1.73E+02 1.13E+02 2.35E+01 9.58E+00 2.87E+00 3.87E+00 a

Max 6.06E+03 6.06E+03 6.06E+03 6.06E+03 6.06E+03 6.06E+03

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a c hemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-20Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Thallium Concentration in Fish Tissue (mg/kg) Figure F

- 20. Baseline Total Thallium Concentration in Trophic Level 3 Fish Tissue in the Immediate Receiving Water

Table F-21 . Total Thallium Concentration (mg/kg) in Fish Tissue (T3) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 4.15E

- 06 4.15E

- 06 1.52E

- 06 1.11E

- 06 0.00E+00 0.00E+00

25 th 1.03E

- 04 9.76E

- 05 8.47E

- 05 3.67E

- 05 0.00E+00 0.00E+00

50 th 9.17E

- 04 9.13E

- 04 8.52E

- 04 4.44E

- 04 6.78E

- 07 9.05E

- 07 a

75 th 1.45E

- 02 1.35E

- 02 1.23E

- 02 6.24E

- 03 4.84E

- 05 4.24E

- 05

95 th 1.56E+00 1.56E+00 1.56E+00 8.08E

- 01 6.07E

- 03 4.51E

- 03

Max 8.07E+01 8.07E+01 8.07E+01 8.07E+01 3.60E+01 3.60E+01

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a c hemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-21Appendix F

—

Additional Model Results

0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Thallium Concentration in Fish Tissue (mg/kg) Figure F

- 21. Baseline Total Thallium Concentration in Trophic Level 4 Fish Tissue in the Immediate Receiving Water

Table F-22 . Total Thallium Concentration (mg/kg) in Fish Tissue (T4) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.59E

- 05 1.59E

- 05 5.83E

- 06 4.26E

- 06 0.00E+00 0.00E+00

25 th 3.92E

- 04 3.73E

- 04 3.24E

- 04 1.40E

- 04 0.00E+00 0.00E+00

50 th 3.51E

- 03 3.49E

- 03 3.26E

- 03 1.70E

- 03 2.59E

- 06 3.46E

- 06 a

75 th 5.53E

- 02 5.15E

- 02 4.71E

- 02 2.39E

- 02 1.85E

- 04 1.62E

- 04

95 th 5.96E+00 5.96E+00 5.96E+00 3.09E+00 2.32E

- 02 1.73E

- 02

Max 3.09E+02 3.09E+02 3.09E+02 3.09E+02 1.38E+02 1.38E+02

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a c hemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.



### F-22Appendix F

—

Additional Model Results

a – The wildlife model applies the same total zinc BCFs for both T3 and T4 fish (see Appendix D ). 0 10 20 30 40 50 60 70 80 90 100 110 120Number of Plant Receiving Waters



### Total Zinc Concentration in Fish Tissue (mg/kg) Figure F

- 22. Baseline Total Zinc Concentration in Trophic Level 3 and Trophic Level 4 Fish Tissue in the Immediate Receiving Water

Therefore, the estimated concentrations presented here are identical for both trophic levels.



### Table F-23 . Total Zinc Concentration (mg/kg) in Fish Tissue (T3 & T4) by

Percentile

Percentile Scenario

Baseline Option 1 Option 2 Option 3 Option 4 Option 5

5 th 1.45E

- 04 1.03E

- 04 5.50E

- 05 4.01E

- 05 0.00E+00 0.00E+00

25 th 3.24E

- 03 2.11E

- 03 1.55E

- 03 8.16E

- 04 0.00E+00 0.00E+00

50 th 2.37E

- 02 1.45E

- 02 1.39E

- 02 7.11E

- 03 2.71E

- 05 1.51E

- 04 a

75 th 9.34E

- 01 6.39E

- 01 4.44E

- 01 1.87E

- 01 1.55E

- 03 6.18E

- 03 a

95 th 4.79E+01 2.47E+01 2.40E+01 1.07E+01 2.59E

- 01 8.43E

- 01 a

Max 2.61E+03 2.61E+03 2.61E+03 2.61E+03 6.51E+02 6.51E+02

a – Under Regulatory Option 4, some plants that discharge both leachate and FGD treat the two waste streams together in a chemical precipitation plus biological treatment system. Under Regulatory Option 5 for these plants, leachate is only treated with a c hemical precipitation system; therefore, for some immediate receiving waters the metal concentrations will increase under Regulatory Option 5 compared to Regulatory Option 4. See the Incremental Costs and Pollutant Removals for Proposed Effluent Limitation Guidelines and Standards for the Steam Electric Generating Point Source Category Report for further discussion of the regulatory option loadings.

b

– The wildlife model applies the same total zinc BCFs for both T3 and T4 fish (see Appendix D ). Therefore, the estimated concentrations presented here are identical for both trophic levels.



### F-23Appendix G

—

Methodology fo r Non-Modeled O ptions



# APPENDIX G

METHODOLOGY FO R N ON -M ODELED O PTIONS

As described in Appendix C (Water Quality Model Methodology), Appendix D (Wildlife Model Methodology), and Appendix E (Human Health Model Methodology), the U.S. Environmental Protection Agency (EPA) performed modeling to estimate the water quality, wildlife, and human health impacts and improvements under Options 1, 2, 3, 4, and 5. EPA did not perform this modeling, however, for Options 3a, 3b, or 4a. Instead, EPA estimated impacts and improvements under these three non

- modeled options by applying adjustment factors to the modeled impacts and improvements under Option 3. This appendix presents EPA’s methodology for developing and applying these adjustment factors, along with the associated limitations and assumptions. 14



### Development of No n- Modeled Option Adjustment Factors

EPA developed adjustment factors by estimating the total pollutant loading removals from the evaluated waste streams under Options 3a, 3b, and 4a and comparing the removals to those under Option 3 to arrive at pollutant

- specific adjustment factors. EPA estimated the pollutant loadings under the non

- modeled options using the wastestream

- specific loadings model output used to develop the five modeled options (Options 1, 2, 3, 4, and 5) and following the methodology describe d in the following memoranda:

• 

### Memorandum to the Rulemaking Record: Methodologies for Estimating Costs and Pollutant Removals for Steam Electric ELG Regulatory Options 3a and 3b (DCN SE03881) – This memorandum documents the methodology for calculating and evaluating the pollutant loadings for Options 3a and 3b.

• 

### Memorandum to the Rulemaking Record: Methodologies for Estimating Costs and Pollutant Removals for Steam Electric ELG Regulatory Option 4a (DCN SE03834)

– This memorandum documents the methodology fo r calculating and evaluating the pollutant loadings for Option 4a.

Using this pollutant loadings dataset, EPA calculated the percent difference in the pollutant loadings 15 

### between options on an immediate receiving water basis. EPA then calculated the average across all immediate receiving waters to arrive at the pollutant

- specific adjustment factors. This methodology assumes that the differences in environmental impacts and improvements between Option 3 and the non

- modeled options are proportional to the dif ferences in pollutant loadings. For example, an option that removes 30 percent less mercury than Option 3 is assumed to achieve 30 percent less mercury

- related environmental improvements than Option

3.

14 Some of the environmental impacts and improvements discussed in this report are present ed in terms of pollutant loadings to sensitive environments and watersheds (e.g., reduced loadings of mercury to waters designated as impaired for mercury, Equa tion C-10 reduced selenium discharges to the Chesapeake Bay watershed). In these cases, to estimate the impact s and improvements under the three non

- modeled options, EPA analyzed the pollutant loadings dataset for the pollutant and receiving water of concern, but did not need to apply the adjustment factor methodology described in this appendix.

15 EPA developed ad justment factors for the 10 metals evaluated in the environmental assessment (EA): arsenic, cadmium, chromium (VI), copper, lead, mercury, nickel, selenium, thallium, and zinc.



### G-1Appendix G

—

Methodology fo r Non-Modeled O ptions



### As shown in Table 6

- 3 of this report, the pollutant re movals under Options 3a and 3b are less than the pollutant removals under Option 3, while the pollutant removals under Option 4a are greater than the pollutant removals under Option 3. This results in positive adjustment factors for Option 4a and negative adjustment factors for Options 3a and 3b. For example, an adjustment factor of 0.25 would indicate that Option 4a removed an additional 25 percent of the pollutants that were not removed under Option 3. An adjustment factor of

- 0.30 would indicate that Opt ion 3a removed 30 percent fewer pollutants than Option 3.

The EA evaluates exceedances of water quality, wildlife, and human health criteria under baseline conditions and each of the regulatory options. Several of these criteria reflect the loadings of mu ltiple pollutants. For example, the EA evaluates exceedances of the National Recommended Water Quality Criteria (NRWQC) for Human Health Organism Only for five pollutants (arsenic, nickel, selenium, thallium, and zinc). To develop an adjustment factor for this overall NRWQC category, EPA calculated the average of the pollutant

- specific adjustment factors for those five pollutants.

Table G-1 presents the pollutant

- specific and criteria

- specific adjustment factors used to estimate environmental impacts and im provements under Options 3a, 3b, and 4a. Table G-2 identifies the pollutants whose adjustment factors were used in calculating criteria

- specific adjustment factors.

Table G-1 . Adjustm ent Factors

Pollutant- Specific Adjustment Factors a

Pollutants Option 3a Option 3b Option 4a

Arsenic

- 0.1670

- 0.1295 0.2720

Cadmium

- 0.2839

- 0.2338 0.2823

Chromium VI

- 0.0861

- 0.0745 0.2920 Copper

- 0.1736

- 0.1361 0.2948

Lead

- 0.1687

- 0.1315 0.3040 Mercury

- 0.2720

- 0.2237 0.2859

Nickel

- 0.2908

- 0.2410 0.2974

Selenium

- 0.3014

- 0.2513 0.2410

Thallium

- 0.2578

- 0.2099 0.3069

Zinc

- 0.2843

- 0.2352 0.2865

Criteria

- Specific Adjustment Factors a

Evaluation Criteria Option 3a Option 3b Option 4a

Freshwa ter Acute NRWQC

- 0.2158

- 0.1757 0.2894 Freshwater Chronic NRWQC

- 0.2253

- 0.1841 0.2840 Human Health Water and Organism NRWQC

- 0.2458

- 0.2005 0.2831 Human Health Organism Only NRWQC

- 0.2602

- 0.2134 0.2808 Drinking Water MCL

- 0.2138

- 0.1738 0.2849

Fish Ingestion NEHC

- 0.2253

- 0.1841 0.2840

Non

- Cancer Reference Dose

- 0.2437

- 0.2007 0.2859

Arsenic Cancer Risk

- 0.1670

- 0.1295 0.2720

Acronyms: National Recommended Water Quality Criteria (NRWQC); Maximum Contaminant Level (MCL); No Effect Hazard

Concentrat ion (NEHC).

a – The adjustment factors are based on pollutant discharge loadings for a total of 297 immediate receiving waters (261 rivers an d streams; 36 lakes, ponds, and reservoirs).



### G-2Appendix G

—

Methodology fo r Non-Modeled O ptions



### Table G-2 . Pollutant

- Specific Adjustment Factors Applicable to Evaluation Criteria

Evaluation Criteria Applicable Pollutant

- Specific Adjustment Factors

As Cd CrVI Cu Pb Hg Ni Se Tl Zn
Freshwater Acute NRWQC X X X X X X X X

Freshwater Chronic NRWQ C X X X X X X X X X

Human Health Water and Organism NRWQC X X X X X X

Human Health Organism Only NRWQC X X X X X

Drinking Water MCL X X X X X X X X

Fish Ingestion NEHC X X X X X X X X X

Non

- Cancer Reference Dose X X X X X X X X

Arsenic Cancer Risk X

Acronyms: Arsenic (As); Cadmium (Cd); Hexavalent Chromium (CrVI); Copper (Cu); Lead (Pb); Manganese (Mn); Mercury (Hg); Phosphorus (P); Selenium (Se); Zinc (Zn).

Note: An “X” indicates that EPA compared the pollutant to a benchmark under the modeled regulatory options for the listed evaluation criteria. EPA calculated the average of the pollutant

- specific adjustment factors (listed in Table

G-1 ) applicable to each criteria to identify the criteria

- specific adjustment factors (listed in Table G-1).



### EPA calculated the adjustment factors for Options 3a and 3b using Equation G-1 and the adjustment factors for Option 4a using Equation G-2 . As described above, EPA first calculated the adjustment factors on an immediate receiving water basis using these equations, then calculated the average across all immediate receiving waters to arrive at the pollutant

- specific adjustment factors presented in Table G-1.

EQUATION G-1 ( L 3ab 

### − L 3 

### )

= AF 3ab 

### L base 

### − L 3



### where:

AF 3ab 

### = Option 3a or 3b adjustment factor (unitless) Output from Equation G-1

L 3ab 

### = Option 3a or 3b pollutant discharge load (lb/year) Pollutant discharge loadings using the methodology presented in Section 10 of

the TDD [U.S. EPA, 2013b].

L 3 

### = Option 3 pollutant discharge load (lb/year) Pollutant discharge loadings using the methodology presented in Section 10 of

the TDD [U.S. EPA, 2013b].

L ba se 

### = Baseline pollutant discharge load (lb/year) Pollutant discharge loadings using the methodology presented in Section 10 of

the TDD [U.S. EPA, 2013b].

G-3Appendix G

—

Methodology fo r Non-Modeled O ptions



### EQUATION G-2

AF 4a 

### = ( L 3 

### − L 4a 

### )

L 3



### where:

AF 4a 

### = Option 4a adjustment factor (unitless) Output from Equation G-2

L 3 

### = Option 3 pollutant discharge load (lb/year) Pollutant discharge loadings using the methodology present ed in

Section 10 of the TDD [U.S. EPA, 2013b].

L 4a 

### = Option 4a pollutant discharge load (lb/year) Pollutant discharge loadings using the methodology presented in

Section 10 of the TDD [U.S. EPA, 2013b].

Application of Non

- Modeled Option Adjustment Factor s

EPA calculated the results presented in Section 6 (Environmental Improvements under the Proposed Regulatory Options) for Options 3a, 3b, and 4a using the equations presented

below.

As discussed above, EPA calculated the adjustment factors for Options 3a, 3b, and 4a using Equation G-1 and Equation G-2

.

EPA used Equation G-3 and Equation G-4 to calculate the number of immediate receiving waters or downstream river miles that exceed an evaluation criterion. EPA calculated these values for Options 3a and 3b using Equation G-3 and for Option 4a using Equation G-4

.

EPA used Equation G-5 and Equation G-6 to calculate the percent reductions under an evaluation criterion. EPA calculated these values for Options 3a and 3b using Equation G-5 and for Option 4a using Equation G-6.

EQUATION G-3

EX 3ab 

### = EX 3 

### × ( EX base 

### − EX 3 

### ) × AF 3ab



### where:

EX 3ab 

### = Number of immediate receiving waters or downstream river miles exceeding an evaluation criterion under Option 3a or 3b (unitless) Output from Equation G-3

G-4Appendix G

—

Methodology fo r Non-Modeled O ptions



### EX 3 

### = Number of immediate rec eiving waters or downstream river miles exceeding an evaluation criterion under Option 3 (unitless) Exceedance presented in

Section 6

EX base 

### = Number of immediate receiving waters or downstream river miles exceeding an

evaluation criterion under Baseline (unitless) Exceedance presented in

Section 6

AF 3ab 

### = Option 3a or 3b adjustment factor (unitless) Output from Equation

G-1 (see Table G-1)

EQUATION G-4

EX 4a 

### = EX 3 

### × ( 1

− AF 4a 

### )

where:

EX 4a 

### = Number of immediate receiving waters or downstream river miles exceeding an evaluation criterion under Option 4a (unitless) Output from Equation G-4

EX 3 

### = Number of immediate receiving waters or downstream river miles exceeding a n evaluation criterion under Option 3 (unitless) Exceedance presented in

Section 6

AF 4a 

### = Option 4a adjustment factor (unitless) Output from Equation

G-2 (see Table G-1)

EQUATION G-5

= ቆ PR 3 

### PR 3ab 

### 100 × ( 1 + AF 3ab 

### ) ቇ

× 100

where:

PR 3ab 

### = Percent r eduction under Option 3a and 3b (unitless) Output from Equation G-5

PR 3 

### = Percent reduction under Option 3 (unitless) Percent reduction presented

in Section 6

G-5Appendix G

—

Methodology fo r Non-Modeled O ptions



### AF 3ab 

### = Option 3a or 3b adjustment factor (unitless) Output from Equation G-1 (see Table G-1)

EQUATION G-6

= ൬ PR 3 

### PR 4a 

### 100 ൰ × AF 4a 

### ൰ × 100 100 + ൬ 1

− PR 3



### where:

PR 4a 

### = Percent reduction under Option 4a (unitless) Output from Equation G-6

PR 3 

### = Percent reduction under Option 3 (unitless) Percent reduction presented

in Section 6

AF 4a 

### = Option 4a adjustment factor (unitless) Output from Equation G-2 (see Table G-1)

Non

- Modeled Option Methodology Limitations and Assumptions

The limitations and assumptions associated with using the equations described above to calculate the impacts to wat er quality, wildlife, and human health under Options 3a, 3b, and 4a

are as follows:

• 

### This methodology assumes that changes in pollutant loadings between Option 3 and

the non

- modeled options result in proportional changes in environmental impacts and improve ments. This simplifying assumption does not account for many of the complexities that are reflected in the receiving water model described in Appendix C (Water Quality Model Methodology), Appendix D (Wildlife Model Methodology),

and Appendix E (Human Healt h Model Methodology).

• 

### As described in Memorandum to the Rulemaking Record: Methodologies for Estimating Costs and Pollutant Removals for Steam Electric ELG Regulatory Option 4a (DCN SE03834), the approach for estimating pollutant loadings under the Option 4a involves the use of adjustment factors and other assumptions. Because the analysis described in this appendix relies upon the estimated pollutant loadings for Option 4a, the limitations and assumptions associated with the loadings estimation methodology also apply to this analysis.

• 

### This methodology relies upon the modeled environmental improvements under Option 3 to estimate the improvements for the non

- modeled options. Refer to Appendix C (Water Quality Model Methodology), Appendix D (Wildlife Model

Met hodology), and Appendix E (Human Health Model Methodology) regarding the limitations and assumptions associated with the receiving water model.

G-6