Attach Address Label

U.S. ENVIRONMENTAL PROTECTION AGENCY 

SECOND FRN VERSION DRAFT 

QUESTIONNAIRE FOR THE STEAM ELECTRIC 

POWER GENERATING EFFLUENT GUIDELINES 

Form Approved 

OMB Control No. 2040-NEW 

Approval Expires xx/xx/xxxx 

The public reporting and recordkeeping burden for this collection of information is estimated to average 197 

hours per response. Send comments on the Agency's need for this information, the accuracy of the provided burden 

estimates, and any suggested methods for minimizing respondent burden, including through the use of automated 

collection techniques to the Director, Collection Strategies Division, U.S. Environmental Protection Agency (2822T), 

1200 Pennsylvania Ave., NW, Washington, D.C. 20460. Include the OMB control number in any correspondence. Do 

not send the completed survey to this address. 
Steam Electric Questionnaire General Instructions 

i Version: February 22, 2010

INTRODUCTION 

The U.S. Environmental Protection Agency (EPA) is collecting data about steam electric power 

generating plants as part of its effort to review and revise the Steam Electric Power Generating effluent 

limitations guidelines and standards (40 CFR Part 423). This questionnaire solicits information from 

plants that generate steam for the primary purpose of producing electricity. 

This survey effort is being conducted under the authority of Section 308 of the Clean Water Act (Federal 

Water Pollution Control Act, 33 U.S.C. Section 1318). All plants that receive this questionnaire must 

respond within 60 days of receipt. Failure to respond, late filing, or failure to comply with the 

instructions may result in criminal fines, civil penalties, and other sanctions, as provided by law. 

BACKGROUND ON EFFLUENT LIMITATIONS GUIDELINES AND STANDARDS (ELGs) 

The Agency recently completed a multi-year study of the Steam Electric Power Generating industry and, 

based on the results, has determined that revising the current effluent guidelines is warranted. EPA’s

decision to revise the current effluent guidelines is largely driven by the high level of toxic-weighted 

pollutant discharges from power plants and the expectation that these discharges will increase 

significantly in the next few years as new air pollution controls are installed. Over the course of the study 

EPA has identified technologies that are available to significantly reduce these pollutant discharges.

Effluent guidelines (i.e., effluent limitations guidelines and standards) are developed pursuant to the 

Clean Water Act and are restrictions that may be applied to industrial discharges. EPA develops ELGs on 

an industry-by-industry basis using information collected during the rulemaking process. 

OVERVIEW OF THE QUESTIONNAIRE 

The questionnaire is divided into the following parts: 

PART A: STEAM ELECTRIC POWER PLANT OPERATIONS; 

PART B: FLUE GAS DESULFURIZATION (FGD) SYSTEMS; 

PART C: ASH HANDLING; 

PART D: POND/IMPOUNDMENT SYSTEMS AND OTHER WASTEWATER TREATMENT 

OPERATIONS; 

PART E: WASTES FROM CLEANING METAL PROCESS EQUIPMENT; 

PART F: MANAGEMENT PRACTICES FOR PONDS/IMPOUNDMENTS AND LANDFILLS; 

PART G: LEACHATE SAMPLING DATA FOR PONDS/IMPOUNDMENTS AND LANDFILLS; 

PART H: NUCLEAR POWER GENERATION; AND 

PART I: ECONOMIC AND FINANCIAL DATA 

EPA’s Office of Water will administer the questionnaire to facilities regulated by the steam electric ELGs. 

The questionnaire will be distributed to all coal-fired power plants and a statistically sampled subset of the 

rest of the steam electric industry. 

The questionnaire consists of multiple sections which have been tailored to address specific processes, 

specific data needs, or types of power plants. Part A of the questionnaire collects general plant 

information and selected technical information about the plant processes and the electric generating 

units. Additional sections of the questionnaire are designed to collect economic data and to collect 

technical information on flue gas desulfurization (FGD) wastewater, ash handling, metal cleaning 

operations, wastewater treatment, surface impoundment and landfill operations, and nuclear operations.

One section of the questionnaire requires certain power plants to collect and analyze samples of leachate 

from surface impoundments and landfills containing coal combustion residues. A detailed table of 

contents listing the specific topics of information requested is located at the beginning of each part of the 

questionnaire. Respondents are required to complete and submit an electronic version of the 

questionnaire. 

Parts A and I of the questionnaire will be sent to all questionnaire recipients; the remaining sections will 

be sent to discrete subpopulations of questionnaire recipients: coal-fired, petroleum coke-fired, oil-fired, 
Steam Electric Questionnaire General Instructions 

ii Version: February 22, 2010

gas-fired, and nuclear plants. Respondents must read the instructions preceding each part to determine 

whether that part needs to be completed for their plant. 

EPA will use the technical data collected in this survey to determine rates and characteristics of 

wastewater generated by the steam electric industry, to develop treatment technology options, and to 

evaluate incremental costs and benefits associated with different regulatory options. For detailed 

information on how EPA plans to use the data obtained from each of the questions, see the document 

titled “Supporting Statement – Questionnaire for the Steam Electric Power Generating Effluent Guidelines 

February 2010” at http://www.epa.gov/guide/steam/. You can also learn more about the rulemaking, 

generally, at the same EPA webpage. 

For some questions, EPA requests information for calendar year 2009. However, some questions request 

information regarding past, present, or future (i.e., “planned”) plant operations. 

COMPLETION OF THE QUESTIONNAIRE 

Each part should be completed by personnel knowledgeable about the information requested. All plants 

must have the corporate official or designee responsible for directing or supervising the response to the 

questionnaire sign the Certification Statement on page vii to verify and validate the information provided. 

Different people may complete each part of the questionnaire. 

See the instructions below for completing the electronic questionnaire. Keep a copy of the completed 

questionnaire, including attachments. EPA will review the information submitted and may request 

your cooperation in answering follow-up questions, if necessary, to complete analyses. 

ELECTRONIC VERSION OF THE QUESTIONNAIRE 

EPA will distribute the questionnaire in electronic format, and respondents are required to submit the

completed questionnaire to EPA in electronic format. The electronic questionnaire has been developed to 

meet the 1998 Government Paperwork Elimination Act (GPEA). 

EPA designed the questionnaire to include many burden-reducing features. The questionnaire was 

designed in modular fashion to reduce respondent burden by making it easier for them to separate and 

distribute questionnaire parts to various plant and corporate staff. The DVD that will be distributed to 

questionnaire recipients will include both the electronic-fillable questionnaire and a pdf-file that can be 

printed out and used as a working copy. Copies of selected sections can be made when needed and 

selected sections of the working copy distributed to the appropriate staff. The electronic questionnaire 

format allows facilities to electronically generate the required number of copies of each section by 

selecting the copy button located at the beginning of the section that may require multiple copies. 

Once the questionnaire is complete, save each Part file to a DVD. It is preferred that diagrams and 

reports or documents submitted with the questionnaire also be saved and submitted on the DVD, if 

possible. The DVD and a hardcopy of the questionnaire must be mailed to the second address listed on 

page v. Do not submit the completed questionnaire and associated documents via e-mail, because the 

document may contain confidential business information. 

HOW TO NAVIGATE THE QUESTIONNAIRE 

EPA formatted the electronic-fillable questionnaire in Microsoft Excel. Each part of the questionnaire is 

its own Excel workbook file that consists of multiple sections and subsections, which are each 

represented by separate tabs (or worksheets) in the workbook. Some parts of the questionnaire contain

more sections than others. Make sure to read through each section and complete every tab within each 

part. Also make sure to completely scroll through every section so that every relevant question is 

answered. An example of the questionnaire format is located below: 
Steam Electric Questionnaire General Instructions 

iii Version: February 22, 2010

Opening the Electronic Form 

1. Download each file from the provided DVD onto your computer's hard drive. 

2. Launch Microsoft® Excel, then select Tools > Macro > Security. In the Security Level tab, select 

"Medium." (Note: This security level allows you to run essential macros contained in the 

electronic form.) 

3. As you open each part of the questionnaire, a security window should appear regarding macros. 

Select "Enable Macros" and then "OK." If the window does not appear, close the file and repeat 

step 2 above. 

Filling out the Electronic Form 

Within the electronic form, yellow highlights indicate blank fields that you must complete. Use your 

mouse or tab key to navigate between blanks. Type in your response, then Tab to the next field. 

Every question is formatted to collect the most consistent answers between each respondent. The format 

of every question is dictated by the type of information requested, summarized below: 

• If a question requires a descriptive or variable response, the respondent must provide a written 

explanation in the highlighted yellow response box located directly below the question. 
Steam Electric Questionnaire General Instructions 

iv Version: February 22, 2010

• If a question instructs the respondent to “check all that apply,” the respondent must select all the 

square-shaped check boxes that correspond to the applicable response options. 

• If a question instructs the respondent to choose only one answer, the response options are 

formatted in one of two ways: 

 

o If a response is formatted as a drop-down-box, click on the arrow and scroll down the list 

to find and select the most applicable option. 

o If a response is formatted as a list of options with corresponding circles, select the circle 

with the most applicable option. 

• If any question does not provide an applicable response option, select “other” and provide a 

written response in the highlighted yellow response box adjacent to the response options or on 

the comments page for that Part. 

Each plant is assigned a plant ID that is listed on the cover letter of the questionnaire. You will need to 

enter the plant name and plant ID in the “Plant Name” and “Plant ID” header fields in the table of contents 

for each part and all header fields throughout the rest of the part will automatically populate. An example 

of the table of contents is located below: 
Steam Electric Questionnaire General Instructions 

v Version: February 22, 2010

QUESTIONNAIRE ASSISTANCE 

WHEN TO RETURN THE QUESTIONNAIRE 

The response to all portions of the questionnaire except Part G is due 60 days after receipt. Part G is 

due 120 days after receipt. 

If you wish to request an extension, you must do so in writing within 21 days of receipt of this 

questionnaire. Written requests may be e-mailed (preferred) or mailed to: 

Jezebele Alicea 

USEPA Headquarters 

Ariel Rios Building 

1200 Pennsylvania Avenue, NW 

Mail Code: 4303T 

Washington, DC 20460 

alicea.jezebele@epa.gov 

Extension requests will be evaluated on a case-by-case basis. Submittal of an extension request to EPA 

does not alter the due date of your questionnaire unless and until EPA agrees to the extension and 

establishes a new date. 

WHERE TO RETURN THE QUESTIONNAIRE 

After completing the questionnaire and certifying the information that it contains, use the enclosed mailing 

label to mail the completed questionnaire to: 

U.S. Environmental Protection Agency 

Questionnaire for the Steam Electric Power Generating Effluent Guidelines 

c/o Eastern Research Group, Inc. 

14555 Avion Parkway, Suite 200 

Chantilly, VA 20151-1102 

CONFIDENTIAL BUSINESS INFORMATION 

If no business confidentiality claim accompanies the information when it is received by EPA, EPA 

may make the information available to the public without further notice. 

Regulations governing the confidentiality of business information are contained in the Code of Federal

Regulations (CFR) at Title 40 Part 2, Subpart B. You may assert a business confidentiality claim covering 

part or all of the information you submit, other than effluent data and information or data that is otherwise 

publicly available, as described in 40 CFR 2.203(b): 

“(b) Method and time of asserting business confidentiality claim. A business which is submitting 

information to EPA may assert a business confidentiality claim covering the information by 

placing on (or attaching to) the information, at the time it is submitted to EPA, a cover sheet, 

stamped or typed legend, or other suitable form of notice complying language such as ‘trade 

secret,’ ‘proprietary,’ or ‘company confidential.’ Allegedly confidential portions of otherwise 

nonconfidential documents should be clearly identified by the business, and may be submitted 

separately to facilitate identification and handling by EPA. If the business desires confidential 

EPA Steam Electric Questionnaire Help Lines

Eastern Research Group, Inc. .............................................................................................................703-633-xxxx 

Internet Electronic Mailing Address (E-mail)............................................................................ steamhelp@erg.com
Steam Electric Questionnaire General Instructions 

vi Version: February 22, 2010

treatment only until a certain date or until the occurrence of a certain event, the notice should so 

state.” 

You may claim as confidential all information included in the response to a question by checking the 

Confidential Business Information (CBI) box next to the question number. Note that plant effluent data are 

not eligible for confidential treatment, pursuant to Section 308(b) of the Clean Water Act, and thus will be 

treated as nonconfidential even if the CBI box is checked. In addition, information that is publiclyavailable should not be claimed confidential. 

If you claim any questionnaire response or other data as CBI, you must specify the portion of the 

response or document for which you assert a claim of confidentiality by reference to page numbers, 

paragraphs, and lines, or specify the entire response or document. This information must be provided 

as part of the submission of the completed questionnaire. Note that EPA will review the 

information submitted and may request your cooperation in providing information to identify and 

justify the basis of your CBI claim. 

If you believe that facts and documents necessary to substantiate confidentiality are themselves 

confidential, please identify them as such so that EPA may maintain their confidentiality pursuant to 40 

CFR Part 2, Subpart B. 

Information covered by a claim of confidentiality will be disclosed by EPA only to the extent of, and by 

means of, the procedures set forth in 40 CFR Part 2, Subpart B. In general, submitted information 

protected by a business confidentiality claim may be disclosed to other employees, officers, or authorized 

representatives of the United States concerned with implementing the Clean Water Act. 

Information covered by a claim of confidentiality will be made available to EPA contractors to enable the 

contractors to perform the work required by their contracts with EPA. All EPA contracts provide that 

contractor employees use the information only for the purpose of performing the work required by their

contracts and will not disclose any CBI to anyone other than EPA without prior written approval from each 

affected business or from EPA's legal office. 
Steam Electric Questionnaire General Instructions 

vii Version: February 22, 2010

Plant Name: 

Plant ID: 

CERTIFICATION STATEMENT 

The individual responsible for directing or supervising the preparation of the questionnaire must read and 

sign the Certification Statement listed below. The certifying official must be a responsible corporate 

official or his/her authorized representative. 

Certification Statement 

I certify under penalty of law that the attached questionnaire was prepared under my direction or 

supervision and that qualified personnel properly gathered and evaluated the information submitted. The 

information submitted is, to the best of my knowledge and belief, accurate and complete. In those cases 

where we did not possess the requested information for questions applicable to our company, we 

provided best estimates. We have to the best of our ability indicated what we believe to be company 

confidential business information as defined under 40 CFR Part 2, Subpart B. We understand that we 

may be required at a later time to justify our claim in detail with respect to each item claimed confidential. 

I am aware that there are significant penalties for submitting false information, including the possibility of 

fines and imprisonment as explained in Section 308 of the Clean Water Act.

 

Signature of Certifying Official Date 

 ( ) 

Printed Name of Certifying Official Telephone Number of Certifying Official 

Title of Certifying Official 

Company Name 
viii Version: February 22, 2010

INSTRUCTIONS FOR COMPLETING THE QUESTIONNAIRE 

Read all question-specific instructions (throughout the questionnaire) and definitions of key terms in the 

questionnaire glossary file. Throughout the questionnaire, key terms are in italics. 

Refer to the code tables located at the end of the each part if prompted to enter a code or complete a block 

diagram. 

Acronyms and measurement units are defined in the Acronyms list at the end of the general instructions. 

Enter the Plant ID on every tab. When completing an electronic form, note the following: When you enter 

your plant name and plant ID in the “Plant Name” and “Plant ID” header fields in the table of contents

for each part, all header fields throughout the rest of the part will automatically populate. 

Not all questions will be applicable to every company or plant. EPA prepared the questionnaire to be 

applicable to a variety of plants; therefore, not all of the questions will apply to every company or plant. Complete 

each relevant item in the questionnaire. 

Mark responses for each question. Fill in the appropriate response(s) to each question. Answer the questions 

in sequence unless you are directed to skip. If you are directed to skip to another section, click on the “Skip to 

Section X” colored hyperlink, which will direct you to the next appropriate section. Do not leave any entry blank. If 

the answer is zero, enter “0". If a question is not applicable to your company or plant, enter or select “NA.” 

Best engineering estimates. EPA is not requiring your company or plant to perform non-routine tests or 

measurements solely for the purpose of responding to this questionnaire, with the exception of companies or 

plants chosen to complete Part G. In the event that exact data are not available, provide best engineering 

estimates and note the methods that were used to make the estimates in the Comments page located at the end 

of each part of the questionnaire. 

Include any clarifying attachments. If additional pages are required to clarify a response, place the associated 

question number, as well as your plant name (if applicable) in the top right corner of each attachment page. The 

following list contains examples of items that may be included as attachments to a response to this questionnaire: 

 – Company brochure, pamphlet, and/or general description; 

 – Process and wastewater treatment flow diagrams;

 – Electronic analytical data collected from monitoring locations; 

 – Equipment operation and maintenance logs; and 

 – Pollution prevention or best management practices (BMPs) policies or data. 

You may need to make multiple copies of some tabs throughout the questionnaire. When completing the 

electronic questionnaire, select the copy button located at the beginning of the section that requires multiple 

copies. Selecting the copy button will generate new worksheets within the Excel file containing the same tables 

and questions from the specific section. Refer to the instructions of the specific section on how to copy the section 

within the part of the electronic questionnaire. If additional worksheets are accidentally generated from selecting 

the copy button, the unneeded worksheets can simply be deleted. 

Pay close attention to the measurement units requested (e.g., gpd). Measurement units are defined in the 

acronyms list at the end of these instructions. Report answers in the units that are specified, unless the question 

requires you to specify the units. 

Indicate information that should be treated as confidential. You may claim as confidential all information 

included in the response to a question by checking the Confidential Business Information (CBI) box next to the 

question number. Note that EPA will review the information submitted and may request your cooperation in 

providing information to identify and justify the basis of your CBI claim. See the CONFIDENTIAL BUSINESS 

INFORMATION section on page v. 

Indicate atypical data in the Comments page at the back of the questionnaire. Year-to-year operations are 

expected to fluctuate, but note in the Comments page if any information is not representative of normal operations 

and why. 

Questions? If you have questions regarding the completion of this questionnaire, see the QUESTIONNAIRE 

ASSISTANCE section on page v.
ix Version: February 22, 2010

ACRONYMS 

ug/L Micrograms per liter 

% Percent 

BTU British thermal unit 

BWR Boiler Water Reactor 

CAS Chemical Abstracts Service 

CBI Confidential business information 

CFR Code of Federal Regulations 

cm/sec Centimeter per second 

DBA Dibasic acid 

deg Degree 

dpy Days per year 

DUNS Dun & Bradstreet Number 

FERC Federal Energy Regulatory Commission 

FGD Flue gas desulfurization 

ft Feet 

FTE Full-time equivalent 

gal Gallon 

gpd Gallons per day 

gpm Gallons per minute 

gpy Gallons per year 

g/L Grams per liter 

hpd Hours per day 

HRSG Heat Recovery Steam Generator 

Kwh Kilowatt hour 

lb Pound 

LOCA Loss of coolant accident 

mg/L Milligrams per liter 

MW Megawatt 

MWh Megawatt hour 

N/A Not applicable 

NOx Nitrogen oxides

O&M Operation and maintenance 

pg/L Picograms per liter 

PHWR Pressurized heavy water reactor 

ppb Parts per billion 

ppd Pounds per day 

ppm Parts per million 

ppt Parts per trillion 

POTW Publicly Owned Treatment Works 

PURPA Public Utility Regulatory Policies Act 

PWR Pressurized Water Reactor 

SCR Selective catalytic reduction 

SEC U.S. Securities and Exchange Commission 

SNCR Selective non-catalytic reduction 

SO2 Sulfur dioxide 

tpd Ton per day 

tpy Ton per year 

TDS Total dissolved solids 

TSS Total suspended solids 

WWT Wastewater treatment 
x Version: February 22, 2010

GLOSSARY 

The terms identified below are identified in the text of this questionnaire in italic font. 

Aerobic biological reactor – A tank in which material is converted from one form into another form by 

microorganisms in the presence of free oxygen. 

Air heater ash – The ash taken from hoppers below the air heater. 

Air heater cleaning wash water – Any water or liquid cleaning solution used for or generated from 

cleaning the air heater. 

Anaerobic biological reactor – A tank in which material is converted from one form into another form by 

microorganisms not in the presence of free oxygen. 

Background concentration – The concentration of a substance in an environmental media (air, water, or 

soil) that is not associated with plant processes or activities. 

Base load unit – A unit normally operated to produce electricity at an essentially constant rate and which 

typically runs for extended periods of time. 

Best Management Practice (BMP) – Pollution prevention practices that help to avoid contact between 

pollutants and water media that may include good housekeeping measures, good management 

techniques, product modifications, operational changes, materials substitution, materials and water 

conservation, and other measures. 

Boiler blowdown – The minimum amount of liquid removed from the boiler/steam generator for the 

purpose of preventing buildup of materials that exceed limits established by best engineering practices. 

Boiler fireside cleaning wash water – Any water or liquid cleaning solution used for or generated from 

cleaning the boiler fireside.

Boiler tube cleaning wash water – Any water or liquid cleaning solution used for or generated from 

cleaning the interior surface of boiler tubes.

Bottom ash – The ash that drops out of the furnace gas stream in the furnace and which settle in the 

furnace or are dislodged from furnace walls. Includes boiler slag collected in wet-bottom furnaces. 

Economizer ash is included when it is collected with bottom ash. 

Bottom ash sluice – Process wastewater generated from a wet bottom ash handling system that is 

formed by combining bottom ash with the bottom ash transport water. Bottom ash sluice is typically 

transferred to a pond/impoundment or a dewatering bin. 

Carbon capture system – An air pollution control system intended to reduce emissions of carbon 

dioxide. Includes both post-combustion and pre-combustion carbon capture/reduction technologies. 

Carbon capture wastewater – Any process wastewater generated from the carbon capture system.

Chemical precipitation/flocculation – Processes involving the addition of chemicals to alter the physical 

state of dissolved and suspended solids and facilitate their removal by sedimentation or filtration.

Clarification – A sedimentation process to remove solid particles from a liquid stream by gravitational 

force. 

Clean Water Act (CWA) – Federal legislation enacted by Congress to “restore and maintain the 

chemical, physical, and biological integrity of the Nation’s waters” (Federal Water Pollution Control Act of 

1972, as amended, 33 U.S.C. 1251 et seq.). 
xi Version: February 22, 2010

Coal pile runoff – The runoff from or through any coal storage pile. 

Coal washing – Coal washing, also known as coal cleaning, entails separating out foreign material from 

coal in a liquid medium and may also include processes to remove ash, sulfur and moisture. The liquid 

medium may be combined with finely ground heavier minerals, such as magnetite, in a dense medium 

fluid, to achieve better separation of unwanted rock and mineral matter from coal particles. 

Cogeneration plant – A generating facility, otherwise known as a combined heat and power plant, that 

produces electricity and another form of useful thermal energy (such as heat or steam), used for 

industrial, commercial, heating, or cooling purposes. 

Combustion turbine cleaning wash water – Any water or liquid cleaning solution used for or generated 

from cleaning a combustion turbine, including the air compressor section of the turbine.

Cost of service – A ratemaking concept used for the design and development of rate schedules to 

ensure that the filed rate schedules recover only the cost of providing the electric service at issue. This 

concept attempts to correlate the utility's costs and revenue with the service provided to each of the 

various customer classes. 

Cycling unit – A unit for which operation is undulated through a generally routine cycle. For example, a 

unit may run daily, but reduce capacity or shut off at night. 

Deep (or shallow) well injection – Disposal of fluids underground through any bored, drilled, or driven 

shaft or a dug hole, improved sinkhole, or a subsurface fluid distribution system where the depth is 

greater than the largest surface dimension. 

Discharge – The conveyance of process wastewater to: (1) surface waters; or (2) a publicly owned, 

privately owned, federally owned, combined, or other treatment works. 

Dry bottom ash handling system – A system that does not use water to convey bottom ash away from 

the boiler. It includes systems that collect and convey the ash without any use of water, as well as 

systems in which bottom ash is quenched in a water bath and then mechanically or pneumatically 

conveyed away from the boiler. 

Dry-bottom boiler – A boiler that contains a dry-bottom furnace, also known as a dry-ash furnace. In a 

dry-bottom furnace, a hopper bottom and sufficient cooling surface are provided so that the ash collecting 

on the furnace walls or the hopper bottom is solid. Dry-bottom boilers are primarily used for coal with high 

ash fusion temperatures. 

Dry FGD system – Dry FGD system, also referred to as semi-dry FGD system, captures sulfur dioxide 

from flue gas by a spray dryer absorption process that produces calcium sulfite with low moisture content. 

Dry fly ash handling system – A system that does not use water to convey fly ash as a dry material 

away from particulate collection equipment. 

DUNS Number – Unique nine-digit numeric sequence (“Data Universal Numbering System”) assigned to 

a corporate entity by Dun and Bradstreet. 

Economizer ash – The ash taken from hoppers below the economizer. 

Evaporation – The process by which water or other liquid becomes a gas. 

FGD scrubber absorber – As depicted in Figure B-1, the FGD scrubber absorber is the module where 

contact between flue gas and sorbent occurs, which results in the capture of sulfur dioxide from the flue 

gas. 

FGD scrubber purge – Process wastewater that exits an FGD scrubber system (typically from a solids 

separation process) and that is transferred to a wastewater treatment system or discharged. Note: The 
xii Version: February 22, 2010

scrubber purge stream may be the same as the FGD slurry blowdown stream if the plant does not 

operate a solids separation system prior to wastewater treatment. Also note that the FGD wastewater 

generated from a single pass FGD scrubber system is referred to as FGD slurry discharge. See Figures 

B-1 and B-2. 

FGD scrubber system – As shown in Figure B-1, a system that captures sulfur dioxide from flue gas. An 

FGD scrubber system may be wet or dry. For wet FGD systems, the solids separation and solids

dewatering processes are part of this system. 

FGD slurry blowdown – Slurry that exits an FGD scrubber absorber to control the solids/chlorides levels 

in the FGD scrubber absorber. FGD slurry blowdown is typically transferred to a solids separation

process. See Figure B-1. 

FGD reagent preparation water –Water used for the preparation of FGD reagent slurry (e.g., water that 

is added to ball mills for limestone slurry preparation). 

FGD reagent slurry – All water that enters into, is used within, or recycles through the FGD scrubber

absorber. FGD slurry water is replenished by make-up water and the solids level is controlled by FGD

slurry blowdown. 

FGD solids – Any solid material generated by the FGD scrubber system. This may also be called FGD 

sludge (e.g., calcium sulfite and calcium sulfate).

FGD solids separation – The process that separates FGD slurry blowdown into two separate streams: 

the solids-rich stream (i.e. underflow) that contains FGD solids and the solids-lean stream (i.e. overflow) 

that contains water and fines. 

FGD solids separation recycle – The FGD wastewater that is returned to the FGD scrubber absorber

following the FGD solids separation process.

FGD System – Please see either dry FGD system or wet FGD system. 

FGD wastewater – Process wastewater generated specifically from the FGD scrubber system.

Filter – An apparatus using woven, granular, or other material to remove solid particles from wastewater 

or water. 

Filter backwash – Any water generated from reversing the direction of flow through a filter for the 

purpose of washing and/or eliminating solids from the filter.

Filter press – An apparatus used in solids dewatering that forces sludge through a filter to remove water 

and form a cake. 

Floor drain wastewater – Liquid collected in any of the floor drains at the plant.

Flue gas mercury control system – An air pollution control system installed or operated for the purpose 

of removing mercury from flue gas. In this questionnaire, do not include FGD or SCR/SNCR systems as 

flue gas mercury control systems.

Flue gas mercury control system wastewater – Any process wastewater generated from the flue gas

mercury control system. 

Fly ash – The ash that is carried out of the furnace by the gas stream and collected by mechanical 

precipitators, electrostatic precipitators, and/or fabric filters. Economizer ash is included when it is 

collected with fly ash. 
xiii Version: February 22, 2010

Fly ash sluice – Process wastewater generated from a wet fly ash handling system that is formed by 

combining fly ash with the fly ash transport water. The fly ash sluice water is typically transferred to an 

ash pond/impoundment.

Forced generator outage – The removal of a generator from the connection with the transmission grid, 

either automatically or manually, that has not been scheduled. These outages are usually the result of a 

mechanical failure of a critical component of the generating system. 

Form 1 – The comprehensive financial and operating report (“Annual Report For Major Public Utilities & 

Licensees’) submitted to FERC for Electric Rate regulation and financial audits by major utilities. 

Gross generation – Amount of power produced by an electric power plant, measured at the terminals of 

the plant (i.e., prior to the point at which the power leaves the station and is available to the system). This 

amount includes electric power generated at a power plant that is used to operate equipment at the plant.

Gypsum cake wash water – Water used to wash gypsum cake to remove impurities (e.g., chlorides). 

Gypsum pile – A temporary storage pile on site containing gypsum. 

Gypsum pile runoff – The runoff from or through any gypsum pile.

Gypsum stacking – For plants that sluice gypsum to a pond/impoundment, the process used to dig out 

the gypsum from the pond/impoundment and stack it along the sides of the pond/impoundment or in 

separate piles for dewatering. 

Gypsum wash water – Process wastewater generated during the solids dewatering operation of gypsum 

or gypsum solids. 

IGCC generating unit – An integrated gasification combined cycle generating unit. 

Immediate parent firm – The first entity in the facility’s ownership structure responsible for facility’s 

expenses associated with steam electric generating units. Note that for the purpose of Part I of the 

questionnaire, if a plant that has multiple owners, detailed financial and economic data are requested of 

the immediate parent firm that holds the largest equity share in the plant. 

Impoundment – See pond/impoundment.

Independent power producer – A corporation, person, agency, authority, or other legal entity or 

instrumentality that owns or operates facilities for the generation of electricity for use primarily by the 

public, and that is not a utility. 

Intake water – Water from public utilities, streams, rivers, lakes, or underground aquifers that is used to 

supply or feed process unit operations or treatment processes. 

Intermediate unit – A unit that is not used in a constant and specific cycle. The unit is instead used more 

sporadically on an as needed basis when energy requirements are less than peak load but more than 

base load. 

Ion exchange – Reversible exchange of ions adsorbed on a mineral or synthetic polymer surface with 

ions in solution in contact with the surface.

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. 
xiv Version: February 22, 2010

Leachate - Liquid, including any suspended or dissolved constituents in the 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 leakage, which are generally used in reference to leachate from an 

impoundment.

 

Leachate collection system - A system that gathers leachate and conveys it to a collection area for 

treatment, discharge, or other use.

 

Leak detection system - A system whose primary purpose is to monitor performance of the containment 

structure of a pond/impoundment or landfill by collecting fluid which flows through the liner.

Liner – A continuous layer of natural or man-made materials, beneath or on the sides of a 

pond/impoundment, landfill, or landfill cell, which restricts the downward or lateral escape of the wastes 

placed therein or leachate.

Major utility – An electric utility (i.e., regulated) that submits a Form 1 comprehensive financial and 

operating annual report to FERC. Major is defined as having (1) one million megawatt hours or more; (2) 

100 megawatt hours of annual sales for resale; (3) 500 megawatt hours of annual power exchange 

delivered; or (4) 500 megawatt hours of annual wheeling for others (deliveries plus losses). 

Method Detection Limit (MDL) – The laboratory's MDL developed as specified in Appendix B of 40 

CFR Part 136. Labs may develop an MDL for their matrix or in reagent water. 

Mill reject sluice – Water stream that is generated by combining mill rejects with water to aid in transport 

and/or disposal. 

Mill rejects – Material such as stone, slate and iron pyrite that is rejected by coal pulverizers because it 

could not be ground. 

Nameplate capacity –The full-load continuous nominal rating of a generator, prime mover, or other 

electric power production equipment under specific conditions as designated by the manufacturer. 

Installed generator nameplate rating is usually indicated on a nameplate physically attached to the 

generator. 

Natural wetlands – A natural area (not man-made) that is saturated by surface or ground water with 

vegetation adapted for life under those soil conditions, as swamps, bogs, fens, marshes, and estuaries.

Non-contact cooling water – Water used for cooling which does not come into direct contact with any 

raw material, product, byproduct, or waste.

Non-pond wastewater treatment unit – A wastewater treatment unit that is not a pond/impoundment. 

Non-pond wastewater treatment units include, but are not limited to: chemical precipitation/flocculation, 

pH adjustment, clarification, anaerobic/aerobic biological reactor, thickeners, and filters. 

Nonutility – A corporation, person, agency, authority, or other legal entity or instrumentality that owns or 

operates facilities for electric generation and is not an electric utility. These entities are not owned by a 

governmental unit or the consumers that the entity serves and do not operate within the traditional costof-service price regulation. Nonutility power producers include qualifying cogenerators, qualifying small

power producers, and other nonutility generators (including independent power producers). Nonutility 

power producers are without a designated franchised service area and do not file forms listed in the Code 

of Federal Regulations, Title 18, Part 141. 

NOx control system – An air pollution control system that prevents NOx formation during fuel combustion 

or removes NOx from flue gas. Types of NOx control systems include, but are not limited to, selective 

catalytic reduction (SCR), selective non-catalytic reduction (SNCR), overfire air, and low NOx burners. 
xv Version: February 22, 2010

NPDES permit – Permits issued under the National Pollutant Discharge Elimination System (NPDES) 

program authorized by Sections 307, 318, 402, and 405 of the Clean Water Act that applies to plants that 

discharge wastewater directly to United States surface waters. 

On site – Property and equipment under the operational control of the plant, including landfills, 

ponds/impoundments, and outfall structures located on non-contiguous property. 

Particulate matter control system – An air pollution control system that removes particulates from the 

flue gas. Particulate matter control systems include, but are not limited to, the following: electrostatic 

precipitators (ESP), fabric filters/baghouses, mechanical collectors, and venturi scrubbers.

Peaking unit – A unit normally used only during peak-load periods of electricity demand or, as an 

example, to replace the loss of another unit. 

pH Adjustment – Changing the acidity or alkalinity of a substance by adding alkaline or acidic materials, 

respectively. 

Plant – Includes all contiguous and non-adjoining property and equipment that is under operational 

control of the facility, including non-adjoining landfills, surface impoundments, and outfall structures. 

Pollutant – Dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, sewage 

sludge, munitions, chemical wastes, biological materials, radioactive materials (except those regulated 

under the Atomic Energy Act of 1954, as amended (42 U.S.C. 2011 et seq.)), heat, wrecked or discarded 

equipment, rock, sand, cellar dirt and industrial, municipal, and agricultural waste discharged into water. 

(See 40 CFR 122.2) 

Pollution prevention – The use of materials, processes, or practices that reduce or eliminate the 

creation of pollutants or wastes. It includes practices that reduce the use of hazardous and 

nonhazardous materials, energy, water, or other resources, as well as those practices that protect natural 

resources through conservation or more efficient use. Pollution prevention includes but is not limited to 

source reduction, in-process recycle/reuse, and water conservation practices. 

Pond/impoundment – A natural topographic depression, man-made excavation, or diked area formed 

from earthen materials or man-made materials or a combination of them, 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 ponds/impoundments include holding, storage, settling, and aeration pits, 

ponds, and lagoons. It does not include building sumps and outdoor collection/transfer concrete basins. 

Pond/impoundment system – A treatment system consisting of one or more ponds/impoundments. 

Pond outlet – The point at which the pond/impoundment releases water to another pond/impoundment, 

surface water, or other process 

Power marketers – Business entities engaged in buying and selling electricity. Power marketers do not 

usually own generating or transmission facilities. Power marketers, as opposed to brokers, take 

ownership of the electricity and are involved in interstate trade. These entities file with the Federal Energy 

Regulatory Commission (FERC) for status as a power marketer. 

Primary purpose – Provides the predominant source of revenue for the plant. The principal reason for 

which the plant operates. 

Priority pollutant – Priority pollutants are a set of 126 chemical pollutants listed at 40 CFR part 423, 

Appendix A.

Privately Owned Treatment Works (PrOTW) – Any device or system which is (a) used to treat wastes 

from any facility whose operator is not the operator of the treatment works and (b) not a “POTW.” 
xvi Version: February 22, 2010

Process operation – One or more pieces of process equipment used to change the physical or chemical 

characteristics of one or more process streams. Process operations include, but are not limited to, 

boilers, scrubbers, SCR/SNCR systems, air heaters, EMC systems, and cooling towers. 

Process wastewater – Any water which comes into direct contact with or results from the storage, 

production, or use of any raw material, intermediate product, finished product, byproduct, or waste 

product. Examples of process wastewater include, but are not limited to, wastewater from ash handling, 

equipment cleaning, air pollution control devices, rinse water, coal pile runoff or other contaminated 

stormwater, and cooling water are considered process wastewater. Process wastewater can be treated, 

recycled, discharged, or hauled offsite for disposal. Sanitary wastewater, non-contact cooling water, 

potable water, sewage, fire protection, car washes, and uncontaminated stormwater are not considered 

process wastewater for the purpose of this information collection request. 

Publicly Owned Treatment Works (POTW) – In general terms, any device or system owned by a state 

or municipality that is used to recycle, reclaim, or treat liquid municipal sewage and/or liquid industrial 

wastes. See 40 CFR part 403.3 for an expanded definition of this term. 

Qualifying Cogenerator and Qualifying Small Power Producer (QF) – A cogeneration or small power 

production facility, respectively, that meets certain ownership, operating, and efficiency criteria 

established by the Federal Energy Regulatory Commission (FERC) pursuant to the Public Utility 

Regulatory Policies Act (PURPA). 

Raw intake water – Intake water prior to any treatment or use. 

Recycle/reuse – To return a stream or a portion of a stream to an earlier step in the process/treatment 

process or to another process at the plant. 

Reporting Limit (Also known by terms, such as Minimum Level, ML, or Quantitation Limit) – The 

laboratory reporting limit in the matrix analyzed. Usually this is a multiple of the MDL, e.g. 3.18 times the

MDL, if seven replicates are used to develop the MDL. This ML maybe rounded to the nearest integer in

this series, 1, 2, 5, or 10. If samples have been diluted the detection and reporting limits should be

increased by the dilution factor. 

Residue – Amount of a pollutant remaining in the environment after a natural or technological process 

has taken place; e.g., the sludge remaining after initial wastewater treatment, or particulates remaining in 

air after it passes through a scrubbing or other process. 

Reverse Osmosis (RO) – A filtration process designed to separate particulate, colloidal, and dissolved 

matter from a liquid using a semi-permeable membrane, where pressure in excess of the osmotic 

pressure is applied to the concentrated side of the membrane. 

RO reject water – Waste water released from the reverse osmosis process. 

Rural Electric Cooperatives – For the purpose of this questionnaire, rural electric cooperatives are 

electric utilities that are legally established to be owned by and operated for the benefit of those using its 

service. This entity will generate, transmit, and/or distribute supplies of electric energy to a specified area 

not being serviced by another utility. Such ventures are generally exempt from Federal income tax laws. 

Most electric cooperatives have been initially financed by the Rural Utilities Service (prior Rural 

Electrification Administration), U.S. Department of Agriculture. 

Sanitary wastewater – Wastewater that is generated from restrooms, cafeterias, showers, and domestic 

(versus industrial) activities. 

Scheduled generating unit outage – The hours during which the generating unit is offline due to 

planned, scheduled repairs, maintenance, or upgrades, such as routine repetitive maintenance and repair 

that have been programmed into the power schedule. 
xvii Version: February 22, 2010

Semi-dry FGD systems – Refer to dry FGD system. 

SCR catalyst regeneration wastewater – Any water generated from the SCR catalyst regeneration

process.

SCR catalyst washing wastewater – Any water generated from the SCR catalyst washing process.

SCR catalyst regeneration – Process by which catalysts used in the SCR system are regenerated after 

a period of time because the catalysts have become less reactive through use. 

SCR catalyst washing – Process by which catalysts used in the SCR system are washed to remove fly 

ash and/or other particulates. 

Settling pond – A pond used to remove solid particles from a liquid stream by gravitational force (i.e., 

sedimentation process). 

Settling tank – A tank that uses a sedimentation process to remove solid particles from a liquid stream 

by gravitational force. 

Sludge – Any solid, semi-solid, or liquid waste generated from a municipal, commercial, or industrial 

wastewater treatment plant, water supply treatment plant, or air pollution control facility exclusive of the 

treated effluent from a wastewater treatment plant. 

Slurry Discharge – Process wastewater that exits a single pass FGD scrubber system and that is 

transferred to a wastewater treatment system or discharged.

Solids dewatering – The process that removes water from the solids-rich stream generated in the solids

separation process. Typically a vacuum belt filter or a vacuum drum filter is used in this process. FGD 

solids such as gypsum are produced by this process.

Steam turbine cleaning wash water –Any water or liquid cleaning solution used for or generated from 

cleaning the steam turbine.

Stormwater runoff – Runoff generated when precipitation from rain and snowmelt events flows over land 

or impervious surfaces and does not percolate into the ground. 

Sulfur dioxide control systems – An air pollution control system that removes sulfur dioxide from flue 

gas. Sulfur dioxide control systems include, but are not limited to: wet FGD systems, dry FGD systems, 

and lime/limestone addition to the boiler. 

Thickener – A sedimentation process to remove solid particles from a liquid stream by gravitational force. 

In contrast to clarification, the primary purpose of the thickener is to increase the concentration of

suspended solids of the feed stream (i.e., to remove liquids), thereby increasing the concentration of

solids in sludge. Note that thickening should not be confused with solids dewatering; the cake formed 

from solids dewatering is handled as a solid and not a liquid. 

Treated (water or process wastewater) – Water that has been processed by physical, chemical, 

biological, or other means to remove specific constituents of the water stream or to alter the physical or 

chemical state of specific constituents of the water stream. 

Treated intake water – Water that is acquired from a source and treated prior to use by physical, 

chemical, biological, or other means to remove specific constituents of the water stream or to alter the 

physical or chemical state of specific constituents of the water stream. 

Ultimate parent firm – The highest level domestic business entity in the facility’s ownership structure. A 

firm that is owned by another U.S. firm is not an ultimate domestic parent firm. In contrast, a U.S. firm that 

is owned by a foreign firm is an ultimate domestic parent firm. 
xviii Version: February 22, 2010

Uncontaminated stormwater – Stormwater runoff that has not come into contact with raw materials,

byproducts, or waste products from the electricity generation process. 

Utility – Any entity that generates, transmits, or distributes electricity and recovers the cost of its 

generation, transmission or distribution assets and operations, either directly or indirectly, through costbased rates set by a separate regulatory authority (e.g., State Public Service Commission), or is owned 

by a governmental unit or the consumers that the entity serves. Examples of these entities include: 

investor-owned entities, public power districts, public utility districts, municipalities, rural electric 

cooperatives, and State and Federal agencies. Electric utilities may have Federal Energy Regulatory 

Commission approval for interconnection agreements and wholesale trade tariffs covering either cost-ofservice and/or market-based rates under the authority of the Federal Power Act. 

Vacuum drum filter – A solids dewatering system that consists of a tank containing a rotating drum 

covered with a cloth filter. A vacuum is used to pull water through the cloth filter to dewater the solids. 

Also referred to as a rotary drum filter.

Vacuum filter belt – A solids dewatering system that uses a vacuum to remove water from solids by 

pulling it through a revolving filter belt.

Variable O&M costs – Operation and maintenance costs that vary directly in proportion to the amount of 

electricity generated by a plant. For the purpose of this questionnaire, variable O&M costs exclude fuel 

expenses, as these are requested separately. Examples of non-fuel variable expenses include: the costs

of water for cooling and condensing; the costs of chemicals for water treatment; the costs of reagents and 

additional cleaning and maintenance for emission control systems; and additional maintenance costs due

to wear and tear on fuel handling, preparation and distribution systems. 

Wastewater treatment – The processing of wastewater by physical, chemical, biological, or other means 

to remove specific pollutants from the wastewater stream or to alter the physical or chemical state of 

specific pollutants in the wastewater stream. Treatment is performed to allow for discharge of 

wastewater or recycle/reuse of wastewater. 

Wastewater treatment system – A combination of one or more wastewater treatment units, other than 

ponds/impoundments, designed to achieve wastewater treatment. 

Wastewater treatment unit – A unit operation used to remove pollutants from process wastewater. 

Wastewater treatment units include, but are not limited to: pond/impoundments, chemical precipitation, 

pH adjustment, clarification, biological reactor, thickeners, filters, and constructed wetlands. 

Waste coal – Usable material that is a byproduct of previous coal processing operations. Waste coal is 

usually composed of mixed coal, soil, and rock (mine waste). Most waste coal is burned as-is in 

unconventional fluidized-bed combustors. For some uses, waste coal may be partially cleaned by 

removing some extraneous noncombustible constituents. Examples of waste coal include fine coal, coal 

obtained from a refuse bank or slurry dam, anthracite culm, bituminous gob, and lignite waste. 

Wet bottom ash handling system – A system in which bottom ash is conveyed away from the boiler 

using water as the transport medium. Wet bottom ash systems typically send the ash slurry to dewatering 

bins or a pond/impoundment.

Wet-bottom boiler – A boiler that contains a wet-bottom furnace, also known as a slag-tap furnace. In a 

wet-bottom furnace, sufficient gas temperature is maintained to keep ash in a liquid, molten state in the 

lower furnace, where is it collected on furnace walls and surfaces. The molten ash is then tapped into 

water tanks that solidify the ash. Wet-bottom boilers are primarily used for coal with low ash fusion

temperatures. 

Wet FGD system – Wet FGD systems capture sulfur dioxide from the flue gas using a sorbent that has 

mixed with water to form a wet slurry, and that generates a water stream that exits the FGD scrubber

absorber.
xix Version: February 22, 2010

Wet fly ash handling system – A system that conveys fly ash away from particulate removal equipment 

using water as the transport medium. Wet fly ash systems typically dispose of the ash slurry in a 

pond/impoundment. 

Zero discharge – Disposal of process and/or non-process wastewaters other than by direct discharge to 

surface water or by indirect discharge to a POTW. Examples include evaporation, deep-well injection, 

hauling, and/or offsite recycle/recovery.