VOLUME I
INTRODUCTION TO THE EMISSION
INVENTORY IMPROVEMENT
PROGRAM
July 1997
Prepared by:
Eastern Research Group, Inc.
Post Office Box 2010
Morrisville, North Carolina 27560
Prepared for:
Steering Committee
Emission Inventory Improvement Program
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DISCLAIMER
As the Environmental Protection Agency has indicated in Emission Inventory Improvement
Program (EIIP) documents, the choice of methods to be used to estimate emissions depends on
how the estimates will be used and the degree of accuracy required. Methods using site-specific
data are preferred over other methods. These documents are non-binding guidance and not rules.
EPA, the States, and others retain the discretion to employ or to require other approaches that
meet the requirements of the applicable statutory or regulatory requirements in individual
circumstances.
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ACKNOWLEDGEMENT
This document was prepared by Joe Mangino of Eastern Research Group, Inc., for the Steering
Committee, Emission Inventory Improvement Program, and for Steve Bromberg of the Emission
Factor and Inventory Group, U.S. Environmental Protection Agency.
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IV EIIP Volume I
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CONTENTS
Section Page
1 Introduction to the Emission Inventory Improvement Program 1.1-1
1.1 Importance of Emission Inventories 1.1-3
1.2 EIIP Committees 1.1-5
1.2.1 Point Sources Committee 1.1-5
1.2.2 Area Sources Committee 1.1-6
1.2.3 Mobile Sources Committee 1.1-7
1.2.4 Biogenic Sources Committee 1.1-7
1.2.5 Quality Assurance Committee 1.1-8
1.2.6 Data Management Committee 1.1-8
1.2.7 Governmental Interactions Committee 1.1-9
1.3 EIIP Committee Products 1.1-9
1.4 Organization of Volume I 1.1-11
2 Implementation of EIIP Guidance 1.2-1
2.1 Purpose of EIIP Guidance 1.2-1
2.2 Scope and General Content of Documents 1.2-4
2.3 Approach for Selecting Methods 1.2-6
2.3.1 Rationale for EIIP's Selection of Methods 1.2-6
2.3.2 Rationale for User's Selection of Methods 1.2-6
3 Training of Inventory Staff 1.3-1
3.1 Topics for Training 1.3-1
3.2 Training Resources 1.3-2
4 Inventory Planning 1.4-1
4.1 Identification of Inventory Uses 1.4-1
4.2 Preliminary Planning Activities 1.4-6
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CONTENTS (CONTINUED)
Section Page
4.2.1 Scope of Inventory 1.4-6
4.2.2 Staff and Resource Considerations 1.4-7
4.2.3 Interagency Communication 1.4-7
4.3 Inventory Work Plan 1.4-9
4.3.1 Source Category Coverage 1.4-11
4.3.2 Selection of Emission Estimation Methods 1.4-12
4.3.3 Data Management and Reporting 1.4-14
4.4 Quality Assurance Plan 1.4-15
5 Inventory Development 1.5-1
5.1 Data Collection 1.5-1
5.2 Data Handling 1.5-3
5.3 Emission Calculations 1.5-4
5.3.1 Source Test Data 1.5-5
5.3.2 Material Balance 1.5-5
5.3.3 Emission Factors 1.5-6
5.4 Emissions Calculation Tools 1.5-7
5.4.1 Factor Information Retrieval System 1.5-7
5.4.2 CHEMDAT8 1.5-8
5.4.3 WATERS 1.5-9
5.4.4 Landfill Air Emissions Estimation Model 1.5-9
5.4.5 TANKS 1.5-9
5.4-6 MOBILESa 1.5-10
6 Documentation and Reporting 1.6-1
6.1 Documentation 1.6-1
6.2 Examples of Standardized Reporting Format 1.6-3
6.3 Electronic Reporting of Data 1.6-8
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CONTENTS (CONTINUED)
Section Page
7 References 1.7-1
8 Glossary 1.8-1
8.1 Point Sources 1.8-1
8.2 Area Sources 1.8-9
8.3 Mobile Sources 1.8-12
8.4 Biogenic Sources 1.8-14
8.5 Quality Assurance 1.8-16
Appendix A: EIIP Committee Member List
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FIGURES AND TABLES
Figures Page
1.1-1 Steps for Implementing the EIIP 1.1-2
1.1-2 EIIP Documents 1.1-4
1.1-3 Data Transfer Using the EIIP Data Model 1.1-10
1.2-1 Emission Inventory Process 1.2-3
1.4-1 Overview of Inventory Planning and Preparation 1.4-2
1.4-2 Interactions in Inventory Development 1.4-8
1.4-3 Process for Selecting Emission Estimation Methods 1.4-13
1.5-1 Example of Inventory Development 1.5-2
Tables Page
1.3-1 Examples of Air Pollution Training Institute Courses 1.3-3
1.3-2 Examples of A&WMA Training Courses 1.3-3
1.4-1 Examples of Inventory Levels 1.4-4
1.6-1 IPCC Summary Report for National Greenhouse Gas Inventories 1.6-4
1.6-2 IPCC Overview Table for National Greenhouse Gas Inventories 1.6-5
1.6-3 Tier 1 and Tier 2 Source Categories 1.6-6
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1
INTRODUCTION TO THE EMISSION
INVENTORY IMPROVEMENT PROGRAM
The Emission Inventory Improvement Program (EIIP) was established in 1993 to promote the
development and use of standard procedures for collecting, calculating, storing, reporting, and
sharing air emissions data. The EIIP is designed to promote the development of emission
inventories that have targeted quality objectives, are cost-effective, and contain reliable and
accessible data for end users. To this end, the EIIP is developing inventory guidance and
materials which will be available to states and local agencies, the regulated community, the public,
and the EPA. The materials prepared under EIIP will:
• Establish standardized procedures for the preparation of emission inventories by
presenting preferred and alternative methods for emissions estimation;
• Promote consistency within inventories among reporting agencies/groups;
• Document consistent quality assurance (QA)/quality control (QC) methods
applicable to all inventory programs;
• Provide guidance to improve the current system of data collection and reporting;
and
• Specify a standard data model and data transfer format to facilitate sharing of data
among agencies.
These guidance materials are being developed for point, area, mobile, and biogenic sources
typically included in air emissions inventories.
The EIIP is a joint program of the State and Territorial Air Pollution Program Administrators and
the Association of Local Air Pollution Control Officials (STAPPA/ALAPCO) and the U.S.
Environmental Protection Agency (EPA). Both of these organizations are represented in the
Standing Air Emissions Work Group (SAEWG), which endorsed the original EIIP plan.
Figure 1.1-1 shows the steps in the implementation of the EIIP. While the EPA coordinates the
EIIP efforts, all of the tasks are performed by working committees made up of state and local
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INTRODUCTION TO EIIP
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SAEWG Approves
EIIP
EIIP Presented To
STAPPA/ALAPCO
STAPPA/ALAPCO
Approves EIIP
EPA & State/Local Agencies
Commit Resources
Steering Committee
is Formed
EIIP Committees are Formed
Point
Area
Mobile
Biogenic
Compile
Emission Inventory
Guidance Manuals
Pilot Test Program
Protocol Revisions
Agency Training
User Feedback
FIGURE 1.1-1. STEPS FOR IMPLEMENTING THE EIIP
1.1-2
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agency personnel, EPA and industry. The following working committees have been formed:
• Steering Committee;
• Point Sources Committee;
• Area Sources Committee:
• Mobile Sources Committee;
• Biogenics Sources Committee;
• Quality Assurance Committee;
• Data Management Committee; and
• Governmental Interactions Committee.
The committees oversee and direct the development of procedural manuals, pilot studies, and all
other activities associated with their particular facet of the inventory. The specific roles and
activities of each of the committees are described in detail in Section 1.2 of this volume.
A significant portion of the guidance material produced thus far appears in a series of EIIP
documents that are specific to each of the working committees. Figure 1.1-2 shows the volume
titles in the initial series of EIIP documents. The methods used in developing the guidance, the
approach taken, and the work products (in addition to the core guidance) have evolved with slight
variations as each committee addresses the issues unique to their particular segment of the
inventory. The scope and content of the EIIP guidance documents are summarized in Section 2.2
of this volume.
1.1 IMPORTANCE OF EMISSION INVENTORIES
An air emissions inventory can range from a simple summary of estimated emissions compiled
from previously-published emissions data to a comprehensive inventory of a facility using specific
source test data that will be used to support compliance activities. Just as there are different types
of emissions inventories, their usage is varied and continually expanding. Because of this wide
use of inventory data, the EIIP will benefit not only state and local air pollution agencies, but
industry and EPA as well.
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FIGURE 1.1-2. EIIP DOCUMENTS
1.1-4
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The applications for emissions inventory data include use of the data in annual trends reports,
State Implementation Plans (SIPs), compliance demonstrations, emissions trading, emissions fees
programs, and in modeling activities designed to evaluate ambient air concentrations encountered
by the general public. For the SIP program, the air emission inventory is a fundamental building
block in developing an air quality control and maintenance strategy. Section 172, Part C, of the
Clean Air Act (CAA) as amended in 1990, which addresses SIP requirements, states that". . .
plan provisions shall include a comprehensive, accurate, current inventory of actual emissions
from all sources or the relevant pollutants or pollutants in such area . . ." Regulatory agencies and
industrial facilities rely on emission inventories on an ongoing basis as indicators of air quality
changes and for setting permit requirements.
Air emission inventories may also be developed for research purposes. For example, concern
over the prospect of global warming has prompted the development of regional, national, and
global inventories of greenhouse gases. At a smaller scale, pilot studies or field tests of new
control techniques or devices may require preparation of emission estimates from a single source
to measure effectiveness of the technique.
The importance placed on emission inventories requires that they be of the highest quality
obtainable considering their end use. Since they are the foundation of many air quality decisions,
inventory quality is critical to defining realistic regulations and attainment strategies. Deficiencies
and inconsistencies in existing compilation processes accentuate the need for developing and
implementing more uniform and systematic approaches to collecting and reporting data. One of
the primary goals of the EIIP is to improve the quality of inventory data so that it is a reliable
source of information for sound decision making.
1.2 EIIP COMMITTEES
Following is a brief description of each of the EIIP committees' goals, and current and planned
activities. While sharing the same overall goals of the EIIP to improve the quality of emission
inventories, each committee is unique in the issues affecting its particular sources and the
approaches used to address those issues. Each committee is chaired by one state/local agency
representative and an EPA representative and is composed of state/local agency, industry, and
EPA representatives.
1.2.1 POINT SOURCES COMMITTEE
The Point Sources Committee (PSC) was formed to develop a series of guidance documents
intended to familiarize the private and government sectors with the basic concepts and procedures
involved in estimating air pollutant emissions from industrial processes as well as to provide
instructional guidance on preferred methods for developing emission inventories. Cumulatively,
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the series of documents will provide a comprehensive set of manuals which will serve the user in
generating a point source emissions inventory.
The PSC seeks participation from several different arenas. The committee works closely with the
EIIP Area Sources Committee to develop guidance manuals on processes common to both types
of inventories, such as surface coating operations. Through information gathering efforts, state
agency workers have been introduced to the EIIP and have joined the working committee, serving
in various roles (some as technical reviewers, some as authors, some as technical advisors). The
PSC has also worked closely with industry and trade associations on document development
efforts. Specifically, the National Asphalt Pavement Association and the National Paint and
Coatings Association (NPCA) have actively participated in document development. PSC
members have toured facility sites with members of these industry groups to better understand
their overall activities.
PSC members have attended meetings of the NPCA and the American Electronics Association to
request their assistance through "partnering" in developing guidance documents for the industries.
During national meetings of the Air and Waste Management Association (A&WMA), the PSC
has surveyed attendees for suggestions and rationale for selecting source categories for guidance
document development. A database with results of these two surveys is maintained by the
committee.
PSC members also spoke with personnel at state air pollution control agencies across the United
States and acquired emissions estimation guidance information pertinent to the industries within
their states. The information was reviewed and, where applicable, emission estimation approaches
were standardized for presentation in the guidance documents. The committee is also actively
involved in the development of the EIIP data transfer model (see Section 1.2.6 for more
information), which will be used as a mechanism for transferring inventory data to other user
formats.
1.2.2 AREA SOURCES COMMITTEE
The primary goal of the Area Sources Committee (ASC) has been to develop improved methods
guidance for area source inventories. Other objectives include:
• Achieve consistency among inventories;
• Provide flexibility in inventory development at the preparing agency level;
• Identify new and innovative methods;
Support planning and QA/QC in inventory development.
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To achieve this goal, the committee surveyed the inventory community to find out which source
categories were seen as high priority for methods improvement chapters in the ASC EIIP
guidance document. Each chapter in Volume III is written to discuss the unique aspects of the
source category. One of the main issues encountered by the ASC in developing their document
was the selection of preferred methods versus alternative methods for presentation in each of the
chapters (see Section 2.3.1 for further discussion on the selection of "preferred" vs. "alternative"
methods).
1.2.3 MOBILE SOURCES COMMITTEE
The main focus of the Mobile Sources Committee (MSC) is to provide specific guidance on how
state and local agencies could better take advantage of potential locality-specific data sources and,
at the same time, retain a known level of quality and completeness in their inventory. Currently,
the committee has concentrated its efforts on onroad mobile sources, specifically on providing
locality-specific inputs for the EPA's MOBILE and California's EMFAC emission factor models.
Also included in the mobile sources document is the development of locality-specific inputs from
transportation demand models and the use of local data for making vehicle miles traveled (VMT)
projections. The specific guidance developed by the MSC is to be used in conjunction with
EPA's existing guidance on procedures for estimating emissions from mobile sources (EPA,
1992a). Future efforts of the MSC include a top-down evaluation of the MOBILE model and
attention to nonroad mobile source issues.
1.2.4 BIOGENIC SOURCES COMMITTEE
The Biogenic Sources Committee (BSC) is composed of members from the EPA, states/local
agencies, and academic institutions. The specific objective of the work of the BSC has been to
develop consistent emission inventory preparation guidance for emissions of volatile organic
compounds (VOC) and nitrogen oxides (NOX) from biogenic sources such as forests, agricultural
crops and soils, lightning, and natural gas and oil seeps.
The BSC's primary work product is a final document of preferred and alternative methods, much
like the point and area source volumes. However, the bulk of Volume V focuses on the use of
Biogenic Emission Inventory System (BEIS)-2 (and similar computer models) for estimating
emissions from vegetation, and addresses the needs of inventory preparers and modelers who
want to develop biogenic emission estimates using these models.
1.2.5 QUALITY ASSURANCE COMMITTEE
The Quality Assurance Committee (QAC) was formed to develop: (1) a plan for the EIIP's QA
program; (2) a comprehensive QA source document of methodologies and tools to use in
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developing emission inventories; and (3) an emission inventory quality rating system. The QAC's
objectives have been achieved though a variety of activities including the development of the
EIIP's Quality Assurance Procedures document (Volume VI), the adaptation of the Data
Attribute Rating System (DARS) for state inventories, and by providing review and assistance on
QA/QC to the other committees.
The QAC reviewed existing EPA guidance (EPA, 1986; EPA, 1988; EPA, 1989; EPA, 1992b;
EPA, 1994a), and felt that while it adequately addressed fundamental QA principles, inventory
preparers needed more concrete guidance that included tools and methods that could be used to
implement QA programs. Furthermore, the issue of uncertainty has become an increasingly
important topic for inventory developers and users; therefore, the QAC expanded the purpose of
emission inventory QA to include measures to document (qualitatively and quantitatively)
uncertainty. The QA volume relies heavily on examples from actual inventories to demonstrate
the use of alternative QA methods.
In addition to the QA volume, the EIIP QAC sponsored training in the use of DARS to evaluate
emission inventories. Workshops were held in which states and local agency personal
participated. The results were used to standardize the DARS, and to develop guidance materials
to assist state and local agencies in evaluating their inventories. The training materials developed
for those workshops are included in the QA volume. The QAC is currently sponsoring the
development of the DARS software system.
1.2.6 DATA MANAGEMENT COMMITTEE
The primary goal of the Data Management Committee (DMC) is to develop and facilitate a data
exchange mechanism for the emission inventory community. The DMC is not producing a
database system but, rather, a standard data transfer format and transfer procedure that is
independent of the databases from which the inventory data originates. Because of the many
different emission inventory data management systems that are used by preparing agencies,
standardization of the inventory data elements, their meaning, and their relationships is necessary
to prepare the transfer/exchange protocol.
The DMC has developed a EIIP Phase I data model (hereafter referred to as the "Data Model")
with its initial effort focussed on the electronic exchange of data for baseline SIP inventories,
attainment demonstration modeling, and air quality strategy development.
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Figure 1.1-3 shows the flow of data using the Data Model. The data transfer format used in the
Data Model is based on the Electronic Data Interchange (EDI) X-12 Standard, which is an
existing and fully functional standard that is accepted by the EPA, other government sectors, and
industry. The DMC envisions future development of the Data Model so that it can be used for
other purposes such as permitting, emission reduction credits, and emission cap and trading
programs.
1.2.7 GOVERNMENTAL INTERACTIONS COMMITTEE
The Governmental Interactions Committee (GIC) examines the relationship between various
agencies and government bodies involved in the emission inventory process. The GIC prepared a
report entitled Roles and Responsibilities of Government Agencies in the Development of
Emission Inventories (EPA, 1995). This report contains guidelines and flow charts which explain
the inventory process and generally define the roles and responsibilities of each participating
group. The discussion focuses primarily on the development of city/county scale inventories that
require some level of EPA review, such as ozone or carbon monoxide nonattainment area SIP
inventories.
1.3 EIIP COMMITTEE PRODUCTS
The initial work products of the EIIP committees include this set of manuals (Volumes I through
VII), a version of the EIIP Data Model, and pilot studies and training using the EIIP version of
the DARS. Hard copies of the manuals are available from the National Technical Information
Service.3 Electronic copies of the EIIP documents can also be retrieved from the CHIEF Internet
World Wide Web site (www.epa.gov/ttn/chief/).
aNTIS, U.S. Department of Commerce, Springfield, VA 22161, telephone (800) 553-6847.
b For information on the different options available to retrieve documents from the TTN
BBS, contact the TTN 2000 helpline at (919) 541-5384.
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FIGURE 1.1-3. DATA TRANSFER USING THE EIIP DATA MODEL
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1.4 ORGANIZATION OF VOLUME I
Section 2 of this document provides details on how to use the EIIP documents, particularly the
usage of "preferred" and "alternative" emission estimation methods.
Section 3 of this volume discusses training considerations for staff who will be preparing
emissions inventories, conducting QA checks, or working with the Data Model. Training is a key
inventory preparation exercise which directly affects the quality of the resulting emissions
inventory.
Inventory planning procedures are covered in Section 4. Planning is another critical step in the
emissions inventory process which cannot be overlooked or trivialized. Careful planning is
needed to assure that inventory end-uses are identified and met, and that time schedules and
resources (personnel and budget allocations) are established that will not compromise the quality
or comprehensiveness of the inventory.
Section 5 discusses inventory development steps in general terms so that inexperienced inventory
preparers can visualize the numerous steps that must be taken in preparing an emissions
inventory.
Reporting and documentation is discussed in Section 6 of this volume. Elements of a written
document, examples of standardized reporting formats, and the increasingly important need for
the electronic transfer of inventory data are covered in this section.
References cited in this volume are presented in Section 7. A glossary of terms commonly used
throughout all the volumes in the EIIP series is presented in Section 8, with the terms grouped by
the subject of each volume (e.g., point sources, area sources). The exception is data management;
because of the technical nature of the terms and symbols used in the data management volume,
the reader is referred to Chapter 1, Appendix B, Data Element Dictionary, of Volume VII.
Appendix A contains a list of EIIP committee members with addresses and phone numbers for
those needing further information on a particular committee.
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IMPLEMENTATION OF EIIP GUIDANCE
2.1 PURPOSE OF EIIP GUIDANCE
The goal of the EIIP is to provide guidance on the development of cost-effective, reliable
inventories by improving the quality of emissions data collected and providing for uniform
documentation and reporting of this information. The EIIP has adopted a philosophy that the use
of standardized emission estimation procedures will produce data of increased precision,
accuracy, and consistency. Using standardized approaches enables industry, federal, state, and
local agencies to generate data of known quality at acceptable costs.
In order to achieve its goal, the EIIP has implemented a system for presenting preferred and
alternative methods for estimating air emissions so that agencies will use this guidance in the
development of their inventories. Emission estimation methods have been delineated for many
point, area, mobile, and biogenic source categories. For example, EPA's widely usedAP-42
document (EPA, 1995-1996) contains many emission factors and source category data that can be
used to estimate emissions. The EIIP guidance does not replace the AP-42 document, but instead
supplements and complements it.
The EIIP's system of preferred and alternative methods selection for estimating emissions allows
users to match the end-uses of their inventory to the inventory development efforts. Inventory
preparers, for example, can select a preferred or alternative estimation method for an individual
source category based on the significance they assign to that source category . By referring back
to the EIIP guidance, subsequent data users can decide whether the quality is adequate to meet
their needs; if it is not, the inventory preparer then has the option of collecting higher quality data
if improved methodologies are available or using an alternative method, if for example, available
resources will not allow the use of a preferred method.
The EIIP's emissions inventory preparation guidance has been developed to ensure that consistent
and unambiguous procedures are used to do the following:
• Identify all emission sources in a defined area. The EIIP provides guidance on
how to identify sources that should be included in an emissions inventory.
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• Select methods to estimate emissions from each source. Guidance is provided
to estimate emissions and choose between preferred and alternative emission
estimation methods based on accuracy.
• Identify and select data sources for activity levels and other parameters
required by an emission estimation method. The EIIP documents specify the
minimum data elements required to estimate emissions for each method and
provides guidelines for obtaining data efficiently.
• Perform QA/QC checks on the inventory. The EIIP QA volume presents
techniques, tools, and methods used for assuring the quality of inventory data.
• Document emission estimation methods, data sources and QA/QC
procedures. Proper documentation is stressed throughout all volumes of the EIIP
documents to ensure reliability and accuracy of results, reproducibility of emissions
estimates, and instill confidence in the inventory.
• Collect and transfer data. Guidance on data collection, storage, and handling is
provided in the guidance documents. The EIIP's Data Model was designed to
standardize data transfer efforts by state and local agencies, industry, and federal
agencies.
Figure 1.2-1 depicts the major processes involved in preparing an emission inventory. The
diagram highlights significant decision points and steps in the implementation of EIIP guidance.
The EIIP guidance allows industry, state, and local agencies to choose the inventory development
method that matches their needs, priorities, and budgets. However, the burden of properly using
inventory data falls on the end-users of the inventory. In the past, many data requestors did not
know the quality of information required to meet their needs, but wanted the "best" data they
could get. The EIIP approach places the responsibility on users to realize that the data may be
inadequate even though it may be the best available. The inventory preparer is strongly
encouraged to document the data quality, evaluate the impact on emissions estimates, and to
prioritize inventory-development efforts to focus resources where they have the most impact.
This will allow end-users to make an informed decision on the use of the data. A discussion of
sources of uncertainty is provided for each source type in Volumes II through V of the EIIP
document series, and methods for assessing uncertainty (quantitatively and qualitatively) are
discussed in Volume VI.
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INTRODUCTION TO EIIP
Establish Emission
Inventory Requirements
I
Use EIIP
Procedures to
Identify All Sources
Needed in Inventory
Select Preferred
Method to Estimate
Emissions for
Each Category
Document
Rationale for
Selection
Alternative
Method
Chosen
Collect Data
Using
Specified
Procedures
I
Compile Data in
State/Local Data
Management System
Requests for
Additional Data
or Re-evaluation
of Methods
Decide if Data
are of Sufficient Quality for Use
or
Adjust Analysis Based on
Precision and Accuracy of Data
Input Data to EIIP Data
Model-based Format for
Transfer and Distribution
FIGURE 1.2-1. EMISSION INVENTORY PROCESS
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2.2 SCOPE AND GENERAL CONTENT OF DOCUMENTS
The following is a summary of the information contained in each of the seven EIIP volumes.
Volume I: Introduction to the EIIP. This introductory volume describes the concept,
implementation, and goals of the EIIP. The EIIP's focus on standardized inventory development
approaches through the selection of preferred or alternative emission estimation methods is
discussed. Also, general emission inventory concepts are explained.
Volume II: Point Sources. The overall goal of Volume II is to familiarize the private sector
with the basic concepts and procedures involved in estimating air pollutant emissions from
industrial processes, and provide instructional guidance to state and local agency personnel on
preferred methods for developing emission inventories. The emission inventory procedures
presented in Volume II are specific to point sources. Practical, detailed calculations and
procedures applicable to specific categories are provided within each chapter. These chapters
present several different estimation scenarios and provide example calculations to aid in actual
emission estimation. A brief discussion is presented on the source category, available control
techniques, and QA/QC. The source classification codes (SCCs) needed for entry of the data into
a database management system are presented. Data collection forms are included as well.
Volume III: Area Sources. Volume III addresses the process of planning and developing an
area source inventory. Fundamental emission estimation approaches are presented, and inventory
management, QA/QC, and documentation procedures are discussed. Each chapter contains a
general description of the source category, an overview of available control technologies, and the
EIIP's preferred and alternative emission estimation methods, including new and innovative
estimation methods where available. A "how-to" approach is provided for each estimation
method. The various methods' uncertainty and data coding procedures are also discussed.
Volume IV: Mobile Sources. Volume IV presents guidance for state and local agencies to use
in developing motor vehicle emission inventories using Highway Performance Monitoring System
(HPMS) and Travel Demand Model (TDM) data. Specifically, Volume IV guides the users in:
(1) the conversion of HPMS vehicle miles traveled (VMT) data to EPA's MOBILE emission
factor model vehicle classes; (2) the use of TDM data for modeling; and (3) the development of
VMT projection data. Preferred methods are presented for each of these three items.
Volume V: Biogenic Sources. Volume V of the EIIP manual series presents preferred and
alternative methods for developing VOC and NOX emission estimates from biogenic sources (e.g.,
forests, crops, and soils), NOX emissions from lightning, and VOC emissions from oil and natural
gas seeps. The assumptions and uncertainty inherent to each of these methods are described, in
addition to the data that must be supplied by the user to estimate emissions. Guidance is provided
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for the three computer models that can be used to estimate biogenic emissions, as well as another
alternative method that involves collecting local information to substitute for defaults in the three
models. Biogenic emission estimation models typically provide emission information in a format
specific to an air quality model. The input needs of the air quality model therefore typically
determine the choice of the biogenic emission estimation model.
Volume VI: Quality Assurance. The purpose of Volume VI is to identify, improve,
consolidate, and document QA/QC practices and procedures in all steps of the inventory
development and review process. The goal of an emission inventory QA/QC program is to
develop and implement techniques for improving inventory consistency and to reduce and
document data uncertainty. Within the context of the EIIP, the emission estimation procedures
and the inventory QA/QC program are complementary. Volume VI presents tools, procedures,
and methods useful for inventory QA/QC. A series of standardized procedures and auditing
steps to be used in implementing the QA/QC program have been developed. The standardized
QA/QC procedures provide guidance for each step of the emission inventory preparation and
reporting process. Also provided are procedures for those using an alternative rather than a
preferred method. The QAC worked with the Point, Area, and Mobile Source Committees to
ensure that inherent uncertainties in emission estimation methods are discussed as fully as
possible.
Volume VII: Data Management. The primary focus of this volume is to provide a unified
standard for defining and sharing emissions inventory data, specifically through defining the use
and implementation of the EIIP Data Model and the EIIP data transfer standard. The EIIP DMC
developed the Data Model to facilitate an improved data exchange mechanism for state and local
agencies, EPA, and industry. The EIIP Point, Area, Mobile, and Biogenic Sources Committees
identified the data elements needed in the Data Model, and were asked to demonstrate how the
data elements related to one another. The resulting organization of the Data Model is similar to
that found in many point source inventory systems. However, in order to accommodate area,
mobile, and biogenic source types for this application, a greater level of abstraction was needed in
terminology as well as in organization. This volume should be used to guide the development of
database translation software programs to convert from an agency's current database to standard
EIIP format (and vice versa). It also provides a common format for industry to use to submit
their data to state/local or federal agencies.
2.3 APPROACH FOR SELECTING METHODS
2.3.1 RATIONALE FOR EIIP's SELECTION OF METHODS
The EIIP consists of several committees whose mandate is to develop concise, accurate, and
innovative inventory development guidance. Emission estimation methods were identified by
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reviewing procedures used or recommended in the past by EPA, state and local agencies, trade
organizations, and research groups. New and innovative emission estimation procedures were
particularly of interest to the EIIP committees. Research and development or source test activities
for developing new emission factors or activity data, for example, are not within the scope of the
EIIP's functions. To select the methods included in the EIIP documents, input was solicited from
committee members and a consensus was reached on identifying which methods to include in the
documents.
An important aspect of the EIIP's selection of methods was the identification of "preferred" and
"alternative" approaches. Selection of a method as preferred or alternative considered several
issues. First, the availability of data needed to use a particular method was considered. Both
preferred and alternative methods had to be practical for each specific source category; the data
had to be available and obtainable with a reasonable amount of effort. Second, the data had to be
of suitable quality for developing an emissions estimate. In general, the preferred method is the
most accurate and precise of the available estimation methodologies. Alternative methods were
identified, however, in the event it was not feasible for the preparing agency to use the preferred
approach. In a few cases, a method was found that was very accurate, but required data that
would either be very difficult or very costly to obtain (or both). A method of this type would not
be selected as the preferred method, but may be included as an alternative.
It is important to emphasize that preferred methods were identified on a source category-specific
basis; this means that a method type identified as preferred for one source category (e.g., AP-42
emission factors) may not be the preferred approach for another source category. This is
consistent with the EIIP's goal of improving the quality of emission estimates for all point, area,
mobile, and biogenic source categories.
2.3.2 RATIONALE FOR USER'S SELECTION OF METHODS
The user of EIIP documents will need to select methodologies that reflect the planned end uses of
the inventory and the priority and importance that the user assigns to a certain source category.
In practice, different procedures will require different commitments of time and resources. The
user should develop realistic selection criteria for inventory methodologies based on staffing,
resource availability, and the time allowed for inventory development.
The end use of the inventory is an extremely important consideration in the selection of methods.
Data of high quality is the goal in all inventories; however, for certain inventory uses, such as
emission limitations and standards, it is imperative that high-quality emission estimates are
pursued. Emission limitations and standards must be legally defensible, and therefore the user
may have to demonstrate that the best available approach was used to prepare the emission
estimates on which they are based.
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The inventory preparer must remember that, in some cases, the quality of emission assessments is
directly affected by the quality of the variables used in the estimation process. Just because a
preferred approach is selected does not mean that a high quality estimate is guaranteed. The
preferred approach, in this example, may require previously collected data to calculate emissions;
the precision and accuracy of these emissions will be based, in part, on the quality of the original
data.
It is important for the user to select their methods and approaches prior to the inventory
preparation. This selection should be done for each source category. It is also important for
users to be flexible about the method selected if the original method selected can not be
performed. For example, a preferred approach may have been selected for an area source
category because it would lead to a higher quality emission estimate. However, upon initiation of
work, the user realizes that appropriate activity level data can not be readily obtained within the
time frame and resources that are allocated. The user may decide that, since this source
category is of relatively low priority, an alternative approach is more suitable to complete the
inventory. The effects of these decisions on the original quality objectives for the inventory,
however, must be considered before proceeding.
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TRAINING OF INVENTORY STAFF
Training of staff members can be a key component of the inventory development process.
Depending on the experience level of the personnel preparing the inventory and the intended end
use of the inventory, training may be a necessary part of the planning process. Appropriate level
of staff training is needed to convey information on basic inventory concepts, types of inventories,
pollutant sources, and inventory development methods. Training is even more important when an
emission inventory is viewed as the fundamental building block in developing an air quality
control and maintenance strategy, or when it will be used to demonstrate compliance with existing
regulations.
3.1 TOPICS FOR TRAINING
The EIIP series of documents identifies some possible topics for training. The discussions on
planning, emission estimation methods, QA/QC, documentation, and database management
highlight key points that should be covered in formal or informal training sessions. The decision
on what type of training is necessary should be based on an evaluation of the experience of the
staff, the technical skills that will be required to prepare the inventory, and the end-use of the
inventory.
Training is an on-going process; training requirements for staff preparing the inventory should be
regularly reviewed so that the latest skills and guidance are made available to them. The type of
training that should be provided depends on the staffs current and future roles and
responsibilities in the inventory program. Some staff require training only on point sources,
others only on area sources or database management. Training of entry-level staff is particularly
important if their long-term goals remain linked to emission inventories and their uses. Since
many of the basic concepts of inventory preparation are repeated in different inventory types,
particularly those that build on previous efforts such as projection and modeling inventories,
consistency among staff is an important issue.
Training should be accounted for in the inventory planning process so that a proper time frame
and mechanism can be established for accomplishing it. This includes budgetary commitments
and the identification of any specialized training resource needs (e.g., computer software and
hardware). There will be some methodologies and tools that are completely new to all staff, and
it will be necessary to identify the appropriate personnel for training.
3.2 TRAINING RESOURCES
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The EIIP document series can serve as a training tool for inventory development personnel, but
the documents are most effective if the user has some basic knowledge of inventories and can
understand the concepts discussed. Depending on the level of experience, there are a variety of
sources for basic and specialized training in inventory development.
Training of inventory development personnel can be conducted on-site with staff members or
off-site through courses offered by agencies such as the EPA. In-house training may consist of
reviewing previously-developed inventories, formal or informal discussions with co-workers and
supervisors on the importance of planning, documentation, and QA/QC. Regular staff meetings
are also necessary to discuss proposed methods, review progress, inform staff of new
methodologies or developments, and allow for in-depth question and answer sessions.
In-house training of inventory staff may not be feasible if experienced personnel do not have time
to provide guidance on a day-to-day basis. Courses offered by the EPA, private consultants, or
trade associations may be a more realistic way for inexperienced staff members to learn the basics
of inventory development, and may be held on- or off-site.
The EPA sponsors numerous training courses through their Air Pollution Training Institute
(APTI).a Table 1.3-1 lists some of the classes routinely offered by APT! Courses are available on
inventory planning, inventory management, point source emissions, emissions calculations,
projection techniques, and data reporting. The A&WMA, in conjunction with EPA, sponsors an
annual conference specifically devoted to emissions inventories. The A&WMA also offers
numerous continuing education courses and workshops throughout the year on air pollution and
solid waste permitting, estimation, control technology evaluation, and waste management issues.
Examples of some of the A&WMA training courses that are offered are shown in Table 1.3-2.
The TTN 2000 Internet web site (www.epa.gov/ttn/chief/) is an excellent on-line resource for
information on training guidance, including documents, memoranda, regulatory news, contact lists
of EPA personnel, and databases. Staff members should regularly review the EIIP and the
Clearinghouse for Inventories/Emission Factors (CHIEF) sections of this web site in order to keep
abreast of the latest information from EPA sources.
a For more information, contact the Training Coordinator at (919) 541-3724.
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INTRODUCTION TO EIIP
TABLE 1.3-1
EXAMPLES OF AIR POLLUTION TRAINING INSTITUTE COURSES
Air Pollution Dispersion Models- Application
Analytical Methods for Air Quality Standards
Atmospheric Sampling
Combustion Evaluation
Continuous Emission Monitoring
Control of Parti culate Emissions
Control of Gaseous Emissions
Introduction to Hazardous Air Pollutants
Overview of the Clean Air Act Amendments
of 1990
Principles and Practices of Air Pollution
Control
Source Sampling for Pollutants
Sources and Control of Volatile Organic Air
Pollutants
TABLE 1.3-2
EXAMPLES OF A&WMA TRAINING COURSES
Fundamentals of New Source Review and
Prevention of Significant Deterioration
Management of Process Fugitive VOC
Emissions
Title V - Operating Permits Workshop
Recent Advances in Continuous Emission
Monitoring
Title III Air Toxics Workshop
Air Dispersion Modeling and Emission
Factors
International Organization for
Standardization/Draft International Standards
(ISO/DIS) 14000 - Environmental
Management Systems
Estimating Fugitive Particulates from Various
Sources
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As discussed throughout the EIIP manuals, the EPA maintains and makes available emissions
inventory development tools for those preparing emissions inventories. The CHIEF portion of the
TTN 2000 contains the entire AP-42 document, each document in the Locating and Estimating
Air Emissions series, the VOC/Particulate Matter (PM) Speciation Database Management System
(SPECIATE), a number of air quality dispersion models, the Factor Information Retrieval (FIRE)
Data System, and emissions models such as TANKS and the Landfill Air Emissions Estimation
Model (LAEEM). The EPA's RACT/BACT/LAER Clearinghouse is also available on the TTN
2000 and contains control technology and permit information for criteria pollutants.
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INVENTORY PLANNING
The reasons for developing an air emissions inventory are often-but not necessarily—regulatory.
Emission regulations or statutes specifically require air emission inventories to determine the
amount of pollutants released to the atmosphere. For example, the Clean Air Act as amended in
1990 sets forth requirements for specific inventories such as SIP base year inventories; in addition,
the development of regulations often necessitates a nationwide inventory of emissions from a
particular industry or type of emission source. On a smaller scale, inventories from a facility are
used as the basis for construction and operating permits, determining compliance with existing
permit conditions or emission regulations, conducting environmental impact assessments for
proposed new sources, and for input to human health risk assessment studies under a variety of air
quality management programs.
Each of these different types of inventories requires advanced planning. Figure 1.4-1 provides an
overview of inventory planning and preparation steps. In general, the data quality needs of the
program will dictate the level of effort required for planning, executing, and quality assuring the
results. The EIIP guidance is focused on the emission inventory development process for a
state/local agency and an individual facility. However, the guidance should also be useful for
planning any level or type of inventory.
This section provides guidance on planning a typical regional inventory of point, area, mobile, and
biogenic sources. Information of general interest or that pertains to all sources is covered. Other
volumes provide details in planning that pertain to specific types of sources. The subject of
planning is divided into four general topics: identification of inventory uses, preliminary planning
activities, inventory work plan, and QA plan.
4.1 IDENTIFICATION OF INVENTORY USES
The end uses of the inventory will dictate the level of effort required for an inventory, the
structure of the inventory, the data quality objectives (DQOs), the required staffing and resource
allocation, and the type of source categories that need to be included. The first step in inventory
planning should be to clearly define the end use, and identify who will be the potential users of the
final product.
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Define Purpose
of Inventory:
this Determines
Level of Detail
Needed
Budget, Schedule,
and/or Objectives
Can
Inventory Needs
be Satisfied with Lower
Quality Data?
Determine Data
Quality Objectives
(DQOs)
Can
Plan be
Modified and Still Achieve
DQOs?
Develop Inventory
Work Plan and
QA plan
Assess
Data/Resources
Available: are
they Adequate
to Achieve
DQOs
Prepare/Revise
Inventory
(Include QA/QC
Activities)
System
Audits:
Problems
Found?
FIGURE 1.4-1. OVERVIEW OF INVENTORY PLANNING AND PREPARATION
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The most common end uses of air emissions inventories include air quality studies, control
strategy development, progress tracking, dispersion modeling, and permitting of facilities. Based
on their different uses, emissions inventories can be categorized into the four general levels as
shown in Table 1.4-1. By assigning an inventory to a category level, the inventory preparer can
follow general staffing, method selection, QA/QC, and documentation requirements as described
throughout the EIIP manuals. A Level I inventory requires the highest degree of defensibility, and
is based on site-specific data. Level I inventories must be sufficient in scope so that their results
can be used directly in compliance or litigation support.
Level II inventories are used to directly support decisionmaking or standard setting, as in the case
of a SIP inventory or a national inventory developed to support a National Emissions Standards
for Hazardous Air Pollutants (NESHAP), New Source Performance Standards (NSPS), or
Maximum Achievable Control Technology (MACT) standard. Site- or region-specific
information are generally required.
In developing a Level III inventory, site-specific data may be gathered, however these inventories
do not directly support rulemaking activities. The results of a Level III inventory may guide
future research efforts. Examples include Superfund Amendments and Reauthorization Act
(SARA) 313 inventories.
Overall inventory preparation and documentation requirements are the least stringent for Level IV
inventories. Level IV inventories are usually compiled from previously- published emissions data,
and are not intended to directly support rulemaking or compliance activities. Level IV inventories
include pure research and development projects, greenhouse gas inventories, and voluntary
internal compliance audits.
There are other inventory uses as well, including:
• Input data for regional air quality modeling;
• Emission trading proposals; and
• Impacts assessments.
These specialized inventory uses will require up-front planning to ensure that all required data
elements are produced and that DQOs are met. Communication with intended users early in the
development process will help to clarify expectations and to begin the planning process.
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TABLE 1.4-1
EXAMPLES OF INVENTORY LEVELS
1
o
D
o
3
Inventory
Category
Description of Example Inventory
Reason(s) for Classification
Level I
Point source data collected by CEM for compliance
purposes.
Operating permits data required under Title V of the
CAA.
Title IV allowance trading program emissions data.
Assessment of emissions required under the
Comprehensive Environmental Recovery and
Comprehensive Liability Act (CERCLA).
Data directly tied to permit fee program, serves as the basis for
emissions limitations and standards, must be legally defensible.
Statutory requirements for CEMs include detailed performance
audits and QA plan.
Data directly tied to permit fee program, used to demonstrate
compliance.
High-quality estimates needed to demonstrate overall reduction
in acid rain emissions, economic incentives.
Used to access the potential toxics exposure at National
Priority List sites, could be related to liability issues.
Level II
rn
T5
1
CD
CAA-mandated SIP inventories.
National inventories developed in support of
NESHAP, NSPS, and MACT standards.
Site-specific information gathered for point sources, stringent
QA/QC requirements, results may be used to support strategic
decision making or standard setting or to evaluate effectiveness
of regulations.
Data used to develop and evaluate emission reduction/control
strategies. Site-specific data generally required, but not
necessarily direct source sampling.
-------
m
T5
CD
TABLE 1.4-1
(CONTINUED)
Inventory
Category
Description of Example Inventory
Reason(s) for Classification
Level III
Inventories required under the Superfund Amendments
and Reauthorization Act of 1986 (SARA 313).
Recordkeeping as part of an integrated plant
maintenance and management program.
May be based on facility-specific information, but
resulting emissions estimates do not directly drive
regulatory development efforts or permit fee programs.
Only penalties are for nonreporting, no QA
requirements specified.
Documentation of maintenance inspections, equipment
cleaning, and damage/repair procedures used to
promote emissions reductions. Need for program is not
directly driven by regulatory program.
Level IV
Inventories of greenhouse gas emissions.
Internal environmental audits.
EPA is required to prepare for Congress a series of
reports on methane emissions form anthropogenic and
natural sources; compiled from previously published
data.
Operations and practices are reviewed to determine if
the facility is meeting its environmental requirements,
and to plan for environmental activities in the future,
need for program not directly driven by regulatory or
permit fee program.
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4.2 PRELIMINARY PLANNING ACTIVITIES
4.2.1 SCOPE OF INVENTORY
The first step of the planning process is to define the scope of the proposed inventory. The
pollutants, emission sources, source categories, and geographical boundaries of the inventory all
need to be identified before data collection begins. All of these factors will help to determine the
scope of the inventory in terms of resources and data needs.
For most inventories, the geographic area covered is typically defined by political boundaries
(county lines, township boundaries, and state boundaries). Inventory areas are collections of
jurisdictions representing air basins or experiencing common air pollution problems. The
inventory purpose determines the exact geographic area covered. For examples, inventories
prepared as part of SIP requirements cover classified ozone or carbon monoxide (CO)
nonattainment areas. A legal listing of these areas and their boundaries is contained in Title 40,
Code of Federal Regulations, Part 81 (40 CFR Part 81). The nonattainment area is designated by
the EPA in conjunction with the states and may change depending on the area's progress in
reaching attainment goals.
Inventories developed for modeling purposes are based on a "modeling region." The modeling
region is defined in terms of the grid boundary that outlines the region and accounts for the size of
the individual grid cells which will be used to subdivide the region. An ozone modeling region
will be larger than an ozone nonattainment area in order to include all major emission sources that
may affect ozone formation in the nonattainment area and to encompass ozone and precursor
pollutant monitoring stations and any additional areas that may have an effect on the modeling
meteorology.
The next step is to specify the pollutants to be inventoried. This must be done before the relevant
source categories can be identified and prioritized. The pollutants of interest for ozone precursor
inventories are VOC, NOX, and CO. Pollutants such as sulfur oxides (SOX), particulate matter
(PM) and CO may be inventoried separately, while a hazardous air pollutant (HAP) inventory
should consider the emission sources of all of the 188 listed HAPs per Section 112(b) of the
1990 CAA or subsequent revisions. Some HAPs may be determined to be insignificant in a
particular inventory area. A greenhouse gas inventory should include emissions of carbon dioxide
(CO2), methane (CH4), nitrous oxide (N2O), and also chlorofluorocarbons (CFCs),
hydrofluorocarbons (HFCs) and perfluorinated compounds (PFCs), and ozone precursors if they
could be significant contributors in the study area.
After the relevant pollutants are delineated, general types or categories of sources to be included
are identified. A SIP inventory has extensive and specific reporting requirements. Point, area,
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mobile, and biogenic sources are typically required and a very thorough accounting of sources
within each of these groups is expected. The extent of the sources to be included is generally
specified where regulations drive the need for the inventory. When this is not the case, it is
important that the inventory planners specify clearly which sources are to be included.
Finally, the inventory scope must specify the spatial and temporal scales at which results will be
presented. More than one scale may be required. A SIP ozone precursor inventory will require
that emissions be calculated on an annual and an ozone season day basis. A point source
inventory may include emissions from individual stacks, plants, or counties, depending on the
spatial disaggregation required by the end user.
4.2.2 STAFF AND RESOURCE CONSIDERATIONS
There must an appropriate commitment of staff and resources to match the level of inventory that
is being prepared. Staff considerations should account for the time needed to complete defined
tasks in the inventory, and the level of experience needed to accomplish those tasks. If there are a
high number of inexperienced staff members, then training will need to be included in the
inventory planning phase. Many of the inventories mandated by regulations will require a
significant time allocation for staff to prepare the initial inventory, make modifications if necessary
based on review of the inventory, and to use the inventory data for specific applications (e.g.,
modeling purposes or projection inventories). Planning must account for the time frame over
which staff will be needed to complete all phases of the inventory.
Resource requirements (e.g., funding, equipment, and training tools) must be established early in
the planning phase. In some cases, not all resource requirements will be met to match the level of
inventory that is desired. In these cases, it will be necessary to prioritize tasks based on available
resources. Estimated budget allocations must be known early in order to plan resource and staff
needs. For example, if a new data management system relies on computer software upgrades that
can not be purchased in the time frame of the inventory preparation, then alternative approaches
much be planned. A useful tool is to develop an integrated time-line that shows budget/resource
allocations next to inventory milestones. This way the preparer can anticipate shortfalls and
possibly reprioritize tasks.
4.2.3 INTERAGENCY COMMUNICATION
In the course of developing an inventory, communications and interactions take place among the
inventory team members, and between the inventory team and other agencies or departments.
Figure 1.4-2 illustrates some of the potential interactions required to develop a SIP (or other
required) inventory within the framework of the EIIP guidance structure. Specific entities that
would be contacted are identified in each of the pertinent EIIP guidance volumes. All types of
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Federal, State, Local Agency
Determine scope
and objectives
of Inventory
Set data
quality objectives
Prepare Inventory
work/QA plan
Prepare
Inventory
External Organizations
Inventory pfennig & development
Requests for hformatlon
^formation suppled
FIGURE 1.4-2. INTERACTIONS IN INVENTORY DEVELOPMENT
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interaction should be considered in inventory planning and should be planned as part of the
definition of responsibilities in the inventory work plan. Key points are:
• Start early, defining necessary interactions and responsibilities while the inventory
work plan is being written;
• Set up schedules and goals;
• Identify contact people for the important inventory tasks and give them plenty of
advance notice of what will be needed from them;
• Schedule routine meetings; and
• Advise management of the schedule and resource needs of the effort, securing their
commitment to the process.
To facilitate communication and information sharing, standardized procedures for collecting and
recording information from telephone contacts and written correspondence are often necessary.
Many examples are provided throughout the EIIP guidance volumes that can be used as a starting
point for developing templates, forms, and other standardized procedures. In particular, see
Volume VI, Quality Assurance Procedures.
4.3 INVENTORY WORK PLAN
The inventory work plan is a concise, prescriptive document that declares how an agency intends
to develop and present its inventory. It should include inventory objectives and general
procedures. The inventory work plan should clearly describe how an inventory preparer plans to
present and document the inventory for submission to the EPA or to other users. The inventory
work plan establishes a line of communication between the preparing agency and the other
departments and agencies that are involved to ensure that the inventory is conducted effectively;
within the preparing agency, it ensures good communication and direction amongst the staff for
the development of the inventory. The EIIP encourages the incorporation of the QA plan as part
of the inventory work plan. The QA plan is discussed separately in Section 4.4 to highlight its
importance in the EIIP planning guidance.
The inventory work plan should clearly describe how an agency plans to present and document
the inventory for submission to the EPA or to other users. The documentation procedures
described in the inventory work plan can facilitate the inventory review process. The inventory
work plan should specify the written and computerized methods that will be used to compile and
report data.
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The inventory work plan will generally:
• Define the geographic area for the inventory;
• Define pollutants to be inventoried;
• Define source categories;
• Define the time interval of the inventory (e.g., annual, seasonal, hourly);
• Provide the background^asis for the inventory (i.e., previous efforts that are
viable and related);
• Identify control strategy programs that will affect the baseline inventory;
• Specify who is responsible for the inventory, with a detailed organization chart of
key personnel/consultants;
• Establish resource requirements, budget allocations, and schedule;
• Specify the QA coordinator (who should be different than the inventory
management or technical staff);
• Set data quality objectives DQOs;
• Define QA/QC procedures for the entire inventory process (i.e., QA plan);
• Define all procedures to be used to determine emissions, including data collection
steps; and
• Specify how the data will be stored, managed, and documented.
In developing the schedule, it is critical to set the major project milestones during planning to
avoid setbacks in achieving the goals identified for the inventory uses. The inventory work plan
should include a timeline that shows when key tasks are expected to be completed so that the
progress of the overall inventory effort can be tracked. This procedure will allow the preparing
agency to more efficiently accommodate changes in labor commitments when priorities change or
problems are encountered.
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Following is a description of some of the key issues in developing the inventory work plan,
including source category coverage, selection of emission estimation methods, and data
management and reporting.
4.3.1 SOURCE CATEGORY COVERAGE
The source categories that are to be addressed in an inventory should be explicitly listed in the
inventory work plan. Typically, source categories fall into one of the following five major source
types: (1) point sources; (2) stationary area sources; (3) onroad mobile sources; (4) nonroad
mobile sources; and (5) biogenic sources. Under ideal conditions all stationary sources would be
considered point sources with emissions determined using detailed site-specific data such as
process throughputs, process parameters, and operating schedules. In practical applications,
however, an emission reporting threshold is usually established to separate point and stationary
area sources.
The EPA has identified numerous source categories for point, area, mobile, and biogenic sources
through its SIP inventory guidance and the series of Locating and Estimating Air Emissions
documents. These references are good starting points for developing a list of source categories in
an inventory area; however, the preparing agency must realize that not all the sources listed in
these documents may be operating in the particular inventory area, and that there also may be
unique sources that are not listed. Since the source category coverage is driven by the pollutants
of interest, it is useful to research possible sources for the particular pollutants and determine if
any are operating in the inventory area. This research should include a review of all of the
documents and tools made available by EPA, the historical and current knowledge of the area,
and current research publications.
All possible source categories for the given pollutant and inventory type should be investigated;
however, due to certain constraints (time, budget, etc.) it may be necessary to prioritize source
categories for inclusion in the inventory. This prioritization should be clearly documented in the
work plan, with the rationale for how the ranking was established. The prioritization may also
help define the level of effort that will be dedicated for each source category that is included.
When source categories are excluded from an inventory, the source categories and the reasons for
their exclusion should be provided in the inventory work plan. Additional emphasis should be
given to categories in which an agency plans to use an approach not specified by previous
guidance. Any major assumptions for emissions estimates development for a category should be
clearly stated.
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The preparing agency may find that subcategorizing a source category will allow for more
detailed and higher quality emission estimates. For example the area source category of "dry
cleaners" can be broken down into coin-operated, self-service machines and commercially
operated businesses. These can be further broken down into units that use perchloroethylene and
those that use petroleum solvents. These different combinations of processes and solvent use
result in different levels of emissions. By breaking down a general source category into specific
types of processes and procedures it may be possible to calculate emissions at a more detailed
level, which will improve the quality of the emission estimate for the overall source category.
4.3.2 SELECTION OF EMISSION ESTIMATION METHODS
Emission estimation methodologies should be determined for each source category during the
planning phase. The choice of methodologies will be based on a number of factors, including
agency resources, source category priority, DQOs, the inventory level (I through IV as described
in Section 4.1 of this document), and the intended uses of the inventory. Figure 1.4-3 shows the
process for selecting emission estimation methods.
The EIIP guidance documents refer to "preferred" and "alternative" methods for each source
category. Selection of a preferred or alternative emission estimation procedure by the user takes
place in the planning stage of the inventory development process, and should be documented in
the work plan. Preferred methods will yield a higher quality estimate of emissions, yet not exceed
a typical state or local agency's capability in terms of resources and staff expertise. These
methods should be used when anticipating a control regulation for the source category, when a
category is ranked as a high priority category, or when a specific local characteristic would skew
the results obtained from an alternative method. In contrast, alternative methods will yield lower
quality estimates of emissions, but are well within any state's capability to perform. These
methods are best used for source categories that are not highly prioritized and for which controls
are not anticipated.
Decisions on the methods to use for individual source categories are affected by the available
resources, source priorities, availability of data, and time schedules. If the available methods vary
in the amount of resources that they require, rank them according to their resource needs and see
how that ranking compares to the prioritized source category list. An increase in resource
allocation may be justified by an increase of accuracy or detail level in the emission estimate. For
example, if the risks of adverse environmental or regulatory effects are high, more sophisticated
and costly emission determination methods may be necessary, such as using continuous emissions
monitors (CEMs) or conducting source tests (for point sources). Conversely, if the risks are low,
less expensive estimation methods may be acceptable.
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Determine Source
Categories to be
Included in
Inventory
Prioritize Source
Categories Based
on Inventory Objectives,
Requirements, and Uses
No
3
Identify Methods
to Calculate
Emissions for each
Source Category
Use DQOs and
Professional Judgement
to Select Method for
each Source Category
I
Is All Information
Needed to Implement
Chosen Method
Available to User?
Yes
FIGURE 1.4-3. PROCESS FOR SELECTING EMISSION ESTIMATION METHODS
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The BARS is another tool that can be used to help select emission estimation methods. The
DARS rating scores are based on the perceived quality of the emission factor and activity data.
Scores are assigned to four data attributes: measurement/method; source specificity; spatial
congruity; and temporal congruity. Using the DARS scores, an inventory preparer can rate the
emission factor and activity data for the methods that are under consideration. Methods could
then be ranked according to their DARS scores and the rankings could be added to a matrix
containing the prioritization and resource allocation rankings.
Another consideration in selecting methods is to compare the needs of the inventory with the
information that the available methods produce. For example, does the method calculate the
pollutant at the required level of detail in terms of speciation, and temporal or spatial allocation?
Does the method reflect economical or regional differences that would affect emissions? These
considerations represent unique conditions in an inventory area and should be considered in
selecting methods.
In some cases the selection of methods is limited. For example, for an onroad mobile source
inventory being prepared to meet SIP requirements, preparing agencies are directed to use the
EPA's MOBILE emission factor model (or EMFAC model in California). Because of the
importance and complexity of these inventories, these emission factor models provide a known
level of quality in terms of the data source and final products that can be used by EPA, states, and
local authorities in setting attainment strategies.
4.3.3 DATA MANAGEMENT AND REPORTING
The inventory work plan should specify the written and computerized methods that will be used
to compile and report data. Planning for the required level of documentation will: (1) ensure that
important supporting information is properly developed and maintained; (2) allow extraneous
information to be identified and discarded, thereby reducing the paperwork burden; (3) help
determine data storage requirements; and (4) aid in identifying aspects of the inventory on which
to concentrate the QA efforts.
One of the biggest challenges in the inventory planning phase, especially for large scale inventory
efforts, is deciding on an efficient strategy to manage and report all of the data that is produced.
The inventory preparer should anticipate the volume and types of data-handling needed in the
inventory effort. If the inventory preparer must deal with large amounts of data, maximizing the
use of computerized inventory data-handling systems will allow them to spend more time
gathering, analyzing, and verifying the inventory data, as opposed to manipulating the data.
Computerized data management also has the advantage of forcing organization, consistency, and
accuracy.
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The selection of the database should be matched to the planned uses of the inventory data. The
format for reporting data can range from a fully documented written report to computer-
generated files for input to other estimation models. Selection of the data management system
should facilitate the reporting format and will depend on several factors:
• Type of computer system;
• Size of the inventory database;
• Complexity of the emissions calculations;
• Number of calculations to be made;
• Variety of tabular summaries to be generated;
• Graphic presentation of data;
• Availability and expertise of clerical and data-handling personnel; and
• Time constraints.
Considerations must also be given to the end-use of the inventory and the required formats for
transferring, sharing and storing data. For example, the EIIP Data Model development program
will require the preparing agency to map certain data elements from its own computerized data
format to the EIIP Data Model transfer protocol. Another example is the transfer of data to
photochemical modelers, who will require certain data elements in order to prepare their models.
In both these examples, the preparing agency must identify the requirements of the receiving
agency in the planning process to ensure that all required data elements and formats are available
for use in the eventual transfer of the inventory data. Upfront planning is critical in developing
most of the computer-based data management programs due to the size of the operations, set-up
time required, training of staff, and the cost involved.
4.4 QUALITY ASSURANCE PLAN
The involvement of QA personnel during the planning stage of the work promotes good
communication between the QA coordinator and inventory development personnel, and enhances
the effectiveness of both the QA and QC programs. It also inherently decreases the number of
quality concerns found during the audits because the expectations are clearly outlined in the QA
Plan and discussed with the inventory development personnel prior to starting the work.
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Listed below are the elements that should be covered in the planning process to ensure
preparation of a quality inventory:
• Identify a QA coordinator;
• Identify DQOs;
• Determine manpower and budget allocations, organizational structure, and
distribution of authority and responsibilities; and
• Develop an inventory work plan that specifically incorporates the QA program
elements (i.e., the QA plan).
The QA plan describes the specific QA/QC procedures and responsibilities of the agency for the
preparation of the emissions inventory. Using a QA plan encourages the development of a
complete, consistent, accurate, and reasonable inventory by implementing specific procedures for
collecting, reporting, and documenting emissions data. Volume VI of the EIIP guidance
document series provides a detailed breakdown of what the QA plan should include and examples
of its applications. A model QA plan is also presented.
QC procedures defined in the plan encompass a system of activities that are designed to ensure
the quality of the inventory in terms of the data collected, emission calculations, and the transfer
and storage of data. QC is typically carried out by members of the project team as the inventory
is being prepared. It is crucial that QC activities are part of an ongoing process in inventory
preparation so as to detect errors prior to the release of a final product. This eliminates the high
cost and time that would be necessary to correct a final product that has a high level of data
uncertainty.
QA is a planned system of activities designed to insure that the QC program is effective and it is
preferable that it involves oversight by individuals who are external and independent of the team.
Systems audits are QA activities that need to be scheduled in the QA plan. Systems audits
evaluate the documentation and procedures associated with the inventory development activities.
Through the use of QA/QC procedures, the inventory and accompanying data will meet a
specified level of quality that minimizes data uncertainty.
The purpose and intended use of the inventory determine the DQOs for the inventory, and drive
the selection of methods. A DQO statement is included in the QA plan to delineate the level of
uncertainty that a decision maker or other user of the inventory is willing to accept. DQO
statements ensure that the final data will be sufficient for its intended use. DQOs are method
specific, are based on the quality of the available data for a given methodology, and are often
based on a review of past inventory efforts and problems.
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The process of developing an acceptable plan is an iterative one. The QA coordinator and
inventory manager(s) must work together to balance the quality objectives with the resources
available. It is important to acknowledge the constraints that limit the ultimate quality of the
inventory, especially if the achievable DQOs fall far short of the desired DQOs.
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INVENTORY DEVELOPMENT
The data needed to develop emission estimates is drawn from a wide range of sources. The
agency may collect some of the data specifically for the inventory effort. Information to support
inventory activities also may be drawn from other agency operations such as permitting,
compliance, and source inspections. For effective use of resources, an agency or facility should
plan to fulfill specific emissions inventory requirements by building upon and improving the
quality of regularly collected data. The following sections describe some of the key steps in
inventory development, including data collection, data handling, and emission calculations. It is
important that QA/QC activities be implemented in all stages of the inventory development
process. Figure 1.5-1 shows an example of the key steps in the development of an inventory and
where QA/QC activities would be necessary.
5.1 DATA COLLECTION
An important step in the planning process is to assess data needs and data collection plans for
point, area, mobile, and biogenic inventories, and to look for possible overlaps. While
development of each type of inventory may be carried out by different staff, data collection and
management should be under central control or oversight. A master file for all records,
memoranda, documents, reports and other references used in the inventory should be established
and maintained.
A major inventory planning consideration is whether, and to what extent, information contained in
existing emissions inventories can be used. Existing inventories should be examined to determine
whether the appropriate sources have been included and that the emissions data represent current
conditions. Existing inventories can serve as a starting point for developing extensive data and
support information, such as documentation of procedures, but often it will be necessary to collect
new data and information to calculate emissions and represent current conditions.
For point source inventories, information may be obtained from contacts with individual facilities.
The two most common types of plant contacts are the mail survey and direct plant inspections. A
type of indirect plant contact also commonly employed is the use of permit applications or
compliance files. Point source emissions must be calculated and reported at the process level
(within a point source) and related to a specific source classification code (SCC). That is,
emissions are to be reported for each SCC rather than at the "point" level within a plant.
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QA/QC
Checks
Revise DQOs
FIGURE 1.5-1. EXAMPLE OF INVENTORY DEVELOPMENT
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Often, time or resources for advanced planning will not be available for a pre-inventory contact of
facilities or a sample of facilities. In such cases, general estimates of process schedules, materials
usage, and other information may be used from the recollections of plant operators and the
available plant records (bills of lading, receipts of raw materials, etc.).
Combinations of these approaches may also be undertaken. For example, a sample of facilities
(either randomly selected or those deemed representative) are contacted before the study period
of the inventory. Information collected for each process should include schedule for the period,
type of materials used, quantity of materials used, and the amount of end product produced.
Emission factors based on the amount of product for each surveyed process could then be used to
estimate emissions from the facilities outside the pre-inventory sample. For example, the amount
of each product shipped from a facility could be collected through facility records and then be
used with an emission factor to determine an emission rate. It should be noted that these
approaches are general in nature. Gaining an accurate picture of the emissions from batch or
intermittent processes may be time consuming and costly.
Surveys used for area and mobile sources will, for practical means, not achieve the same level of
coverage as those used for the larger point sources. This reflects the fact that the area and mobile
sources are individually small, but much more numerous than point sources. Emissions are
estimated for area and mobile sources by selecting representative subsets of individual sources
from which emission calculation parameters can be derived and then scaled up to reflect the entire
population of these sources. When planning to collect survey data for area and mobile sources it
is critical that the subset of individual sources be carefully selected so that they are representative
of the population as a whole. For example, the emission factors presented for
consumer/commercial solvent use and architectural coatings in Volume III of the EIIP series were
developed from surveys of manufacturers. Those surveys attempted to cover as many sources as
possible, and where manufacturers could not be included, the uncovered contribution was
quantified to make the emission factors more representative of the industry as a whole.
5.2 DATA HANDLING
Data handling will rely to some extent on the selection and use of a computer database system.
Because many inventories produce a large quantity of data, it is essential to choose a
computerized data management system that meets all the required function and storage
requirements of the inventory effort. After a system is selected, a plan for data flow should be
implemented to ensure that the data are handled properly in the different stages of inventory
development, and that QC checks are in place.
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Some activities that can be performed efficiently and rapidly by computers:
• Printing mailing lists and labels;
• Maintaining status reports and logs;
• Calculating and summarizing emissions;
• Performing error checks and other audit functions;
• Storing source, emissions, and other data;
• Sorting and selectively accessing data; and
• Generating output reports and graphical presentations.
Where data are not stored on electronic files, the inventory preparer must document all manually
calculated emissions on worksheets. These worksheets should become part of the final
documentation of the inventory when completed. In all cases, whether emissions are calculated
by hand or with computer spreadsheets, all assumptions should be clearly stated and all data used
in the emissions calculation should be referenced.
An important QA/QC aspect to data handling is the transcription of data during the inventory
preparation. There must be checks built into the process for handling data that comes from the
raw calculations sheets and is reported, summarized, or otherwise manipulated in some other
form. It may be possible to build these checks into the computer database that is handling the
data. For example, for electronic data entries it may be possible to reject an entry if it exceeds a
reasonable or expected value. Otherwise, sample QC checks tracking the data manually from its
generation to its final use may suffice.
5.3 EMISSION CALCULATIONS
The steps involved in calculating emissions will depend on the particular estimation technique that
is selected in the planning phase for each source category. Most emission calculations are based
on one of the following types of data or procedures: (1) source test data; (2) material balance;
and (3) emission factors. The following sections briefly describe the basic concepts of each; for
detailed procedural guidance, the reader is directed to Volumes II through V.
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5.3.1 SOURCE TEST DATA
The best method of estimating a source's emissions can be the use of test data obtained by the
preparing agency or supplied by the plant itself. The use of source test data reduces the number
of assumptions regarding the applicability of emissions data to a source (a common consideration
when emission factors are used), as well as the control device efficiency, equipment variations,
and fuel characteristics. Of course, the testing must be properly conducted over a sufficiently
long period of time to produce results representative of conditions that would prevail during the
time period inventoried. The most complete type of source testing is continuous emissions
monitoring (CEM). CEM measures and records actual emissions during the time period the
monitor is operating and the data produced can be used to estimate emissions for different
operating periods.
Two items should be noted when using source test data to calculate emissions. First, because
most source tests are generally only conducted over several hours or days at most, adjustments
may need to be made when using these data to estimate emissions over longer time intervals or for
conditions different from those under which the tests were performed. Second, a source test
supplied by a plant may not adequately describe a given facility's annual or seasonal operating
pattern. The amount of time that a control device actually operates at peak efficiency will also
greatly impact the accuracy of the emissions estimate. In those cases where such data are not
included in the test reports, the range of operation on an annual basis should be researched so that
reliable annual or seasonal emissions estimates can be made. The information can be obtained by
contacting the plant. Although the information could be obtained from questionnaire data, it may
not be as accurate as that obtained from a direct query.
5.3.2 MATERIAL BALANCE
An agency can in some cases use material balance considerations to estimate emission factors or,
better yet, total emissions for an inventory period. For some sources, a material balance can be a
practical method of estimating certain emissions, such as VOC, and can be the most accurate,
especially when the balance covers the entire inventory period and the nonair losses are small or
easily measured. Emissions from solvent evaporation sources are most commonly determined by
the use of material balances.
Use of material balances involves the examination of a process to determine whether emissions
can be estimated solely on knowledge of operating parameters, material compositions, and total
material usage. The simplest material balance assumes that all solvent used in a process will
evaporate to become air emissions somewhere at the facility. For instance, for many surface
coating operations, it can be assumed that all of the solvent in the coating evaporates to the
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atmosphere during the application and drying processes. In such cases, emissions equal the
amount of solvent contained in the surface coating plus any added thinners.
Material balances are greatly simplified and very accurate in cases where all of the consumed
solvent is emitted to the atmosphere. But many situations exist where a portion of the evaporated
solvent is captured and routed to a control device such as an afterburner (incinerator) or
condenser. In these cases, the captured portion must be measured or estimated by other means
and the disposition of any recovered material must be accounted for. As a second example, in
degreasing operations, emissions will not equal solvent consumption if waste solvent is removed
from the unit for recycling or incineration. A third example is where some fraction of the diluent
(which is used to liquify cutback asphalt, for example) is believed to be retained in the substrate
(pavement) rather than evaporated after application. In these examples, a method of accounting
for the non-emitted solvent is required to avoid an overestimation of emissions.
Material balances cannot be accurately employed at a reasonable cost for some evaporation
processes because the amount of material lost is too small to be determined accurately. As an
example, applying material balances to petroleum product storage tanks is not generally feasible
because the losses are too small relative to the uncertainty of any metering devices. In these
cases, AP-42 emission factors or equations can be used.
5.3.3 EMISSION FACTORS
One of the most useful tools available for estimating emissions from point, area, and mobile
sources is the emission factor. An emission factor is an estimate of the quantity of pollutant
released to the atmosphere as a result of some activity such as combustion or industrial
production, divided by the level of that activity. In most cases, emission factors are expressed
simply as a single number, with the underlying assumption that a linear relationship exists between
emissions and the specified activity level over the probable range of application.
Because such factors are typically averages obtained from data with a wide range of
representation and varying degrees of accuracy, emissions calculated this way for a given facility
are likely to differ from that facility's actual emissions. Because they are averages, factors will
indicate higher-than-actual emissions for some sources and lower-than-actual emissions for
others. Only specific source measurement can determine the actual pollutant contribution from a
source, under conditions existing at the time of the test. For the most accurate emissions
estimate, it is recommended that source-specific data be obtained whenever possible.
Emission factors are more appropriately used to estimate the collective emissions of a number of
sources, such as is typically done in emissions inventory efforts for area sources in a particular
geographic boundary. If factors are used to predict emissions from new or proposed sources, an
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agency should review the latest literature and technology to determine whether such sources
would likely exhibit emissions characteristics different from those of typical existing sources.
5.4 EMISSIONS CALCULATION TOOLS
This section gives a brief overview of emission factor databases, models, and other available
information that may be useful for inventory preparation. Specific emissions measurement are
generally the best and most accurate method to quantify emissions; however, source data are not
always available. As an alternative, documents and databases containing emission factors and
models can be used as tools to estimate air pollutant emissions for inventory purposes. The
calculation of area source emissions relies to a great extent on the use of emission factors since it
is usually the most efficient approach to estimating emissions from these sources. Models often
use computers, so that a large number of equations and interactions can be easily manipulated and
the effect of many different parameters can be accounted for. EIIP guidance can be incorporated
into the use of many of these tools, and some (e.g., the EIIP mobile source guidance) rely
specifically on the use of these tools (e.g., the MOBILE emission factor model for estimating
mobile source emissions).
5.4.1 FACTOR INFORMATION RETRIEVAL SYSTEM
The EPA's Factor Information Retrieval System (FIRE) is a consolidation of emission factors for
criteria pollutants and HAPs that includes emission factors from EPA documents such as AP-42
and the Locating and Estimating Air Emissions series, factors derived from state- reported test
data, and factors taken from literature searches . These references are the basic sources of
emission factors that have been used in the preparation of inventories, as well as economic
analyses, permit preparation for prevention of significant deterioration and New Source Review
applications, and other federal, state, and local agency assessments of air pollution sources.
Each emission factor in FIRE also includes information about the pollutant (Chemical Abstract
Service [CAS] numbers and chemical synonyms) and about the source (Standard Industrial
Classification [SIC] codes and descriptions, and SCCs and descriptions). Each emission factor
entry includes comments about its development, in terms of the calculation methods and/or source
conditions, as well as the references where the data were obtained. The emission factor entry also
includes a data quality rating.
The FIRE database has been designed to be very "user friendly." Data can be searched in many
different ways and can be downloaded to data files, or can be printed in a report format that is
designed by the user. The FIRE database can be accessed from the EPA's CHIEF Internet web
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site on the TTN 2000. FIRE is also available on the Air CHIEF CD-ROM as a compact disc
read-only memory (CD-ROM) form and can be obtained by calling the Info CHIEF Help Desk at
(919)541-1000.
5.4.2 CHEMDAT8
CHEMDAT8 is a Lotus®l-2-3 spreadsheet prepared by the EPA's Emissions Standard Division
that includes analytical models for estimating VOCs from treatment, storage and disposal facility
(TSDF) processes. The original models include disposal impoundments, closed landfills, land
treatment facilities, and aeration and nonaeration impoundment processes. Predicted emissions
can be viewed on the screen or printed. A graphical presentation of the relationships between
emission prediction and vapor pressure and between emission prediction and the partition
coefficient is also available. The resulting scatter diagrams can be printed via PrintGraph®,
another Lotus® program.
The models in CHEMDAT8 can be applied to other types of TSDF processes besides those
contained in the original design. The nonaerated impoundment model in CHEMDAT8 can
estimate emissions from storage surface impoundments and open-top wastewater treatment tanks.
The CHEMDAT8 model for predicting emissions from surface treatment impoundments and
aerated wastewater treatment tanks is the aerated impoundment model. The land treatment model
in CHEMDAT8 can estimate emissions from land treatment soil, open landfills, and waste piles.
Emissions from an oil film surface in a land treatment facility or an oil film on surface
impoundments can be predicted via the oil film model in CHEMDAT8. When a CHEMDAT8
model is not available to predict emissions, the equations shown in the reports that provide the
background to the model can be used to perform hand calculations of emissions.
Default input parameters in the CHEMDAT8 diskette demonstrate example calculations.
However, the input parameters can be changed to reflect different TSDF characteristics and then
recalculate emissions under these modified conditions. The list of 60 compounds currently in
CHEMDAT8 can be augmented by an additional 700 chemicals. Procedures for introducing data
for additional compounds into CHEMDAT8 are described in the supporting documentation
report.
For more information about CHEMDAT8, contact the EPA's Emissions Standards Division at
(919) 541-5499. Executable code and documentation for CHEMDAT8 can be downloaded from
the TTN 2000 Internet web site.
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5.4.3 WATERS
WATERS is a menu-driven computer program that is intended for estimating emissions from
wastewater treatment systems only. WATERS uses some of the same models found in
CHEMDAT8, but has data for over 950 compounds. Recent updates to this model have added
routines to estimate emissions from collection system elements such as trenches, conduits,
junction boxes and manholes. For more information about WATERS, contact the EPA's
Emission Standards Division at (919) 541-5499. The executable code and documentation for
WATERS can also be downloaded from the TTN 2000 Internet web site .
5.4.4 LANDFILL AIR EMISSIONS ESTIMATION MODEL
The Landfill Air Emissions Estimation Model (LAEEM) is a computer program specifically
designed for use by state and local regulatory agencies to monitor the air emissions from landfills.
The system allows the user to enter specific information regarding the characteristics and capacity
of an individual landfill and to project the emissions of methane, CO, nonmethane organic
compounds, and individual HAPs over time using the Scholl Canyon decay model for landfill gas
production estimation. The Scholl Canyon Model is a first-order decay equation that uses site-
specific characteristics for estimating the gas generation rate. In the absence of site-specific data,
the program provides default values for regulatory uses of the model, and default values drawn
from AP-42 for inventory uses. The user also may tailor decay rate characteristics on an
individual basis. An integrated decay rate constant calculator is provided for landfills that may be
operating a gas recovery system to allow more accurate assessments of decay attributes. Outputs
may be reviewed in either tabular or graphical forms. A help system is also provided with
information on the model operation as well as details on assumptions and defaults used by the
system.
The LAEEM is available on the Control Technology Center (CTC) portion of the TTN 2000
Internet web site. The model is IBM PC-compatible, requires at least 512 kilobytes of memory,
and can be used with a monochrome or color graphics adaptor. For additional information
contact the EPA's Air Pollution Prevention and Control Division, Office of Research and
Development, Research Triangle Park, North Carolina, at (919) 541-2709.
5.4.5 TANKS
The TANKS program is designed to estimate emissions of organic chemicals from storage tanks.
The calculations are performed according to AP-42 equations. The user provides specific
information concerning the storage tank and its contents; the TANKS program then estimates the
annual or seasonal emissions and produces a report. The emissions can be separated into
breathing and working losses.
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The TANKS program has a chemical database of over 100 organic liquids and meteorology data
from over 250 cities in the United States. The user may add new chemicals and cities to their
version of the database. The tank styles addressed in the program include vertical and horizontal
fixed roof tanks, and internal and external floating roof tanks. The tank contents can consist of
single or multiple liquid components.
TANKS version 3.0 is currently available. The emission estimating equations that form the basis
of the TANKS 3.0 software program were developed by the American Petroleum Institute (API).
The API retains the copyright to these equations but has granted permission for the nonexclusive,
noncommercial distribution of this material to governmental and regulatory agencies. The API,
however, reserves the rights regarding all commercial duplication and distribution of its material.
Therefore, the TANKS program is available for public use, but the program cannot be sold
without written permission from the API, the U. S. EPA, Midwest Research Institute, and Perrin
Quarles Associates, Inc. The TANKS 3.0 program is written in FoxPro2.5,™ and is distributed
by the EPA through the TTN 2000 Internet web site or through the mail on diskette.
5.4.6 MOBILESa
At the time of this writing, MOBILESa is the EPA's current version of the emission factor model
for use in preparing onroad mobile source emission inventories (there is a MOBILESb version
that can be used for certain modeling scenarios only). Since this model is regularly updated and
revised, the user is directed to the EPA's Office of Mobile Sources (OMS) Internet web site
located on the TTN 2000 to obtain the latest information on this model.
The major function of MOBILESa is to calculate emission factors for gasoline- and diesel-fueled
light-duty vehicles, light-duty trucks, heavy-duty vehicles, and motorcycles. These motor vehicle
types are also grouped by low- and high-altitude areas of the United States. Specifications on the
required use of variables, such as temperature, speed, and other factors, are also provided.
MOBILESa is capable of calculating emission factors for any calendar year between 1960 and
2020 and it includes provisions for modeling the effects of oxygenated fuels on exhaust CO
emissions.
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DOCUMENTATION AND REPORTING
The goal of inventory documentation is to ensure that the final written report or compilation of
data accurately reflects the inventory effort. At a minimum, documentation should be sufficient
to determine quality of emissions estimates, identify the data references, and allow reproducibility
of emissions estimates. A successful inventory report also addresses the original goals for
preparing the inventory and provides summary data and documentation that allow the quality of
the inventory effort to be effectively judged. It also facilitates quality review of the inventory,
executive decision-making based on the data, and updates and modifications to the inventory.
The following sections discuss typical documentation requirements for preparing an inventory
report and options for the electronic reporting of data. Refer to each of the pertinent volumes on
point, area, mobile, and biogenic sources for detailed reporting procedures for those source types.
6.1 DOCUMENTATION
The specific documentation required for an inventory will vary based on the end use of the
inventory. The definitions of the Level I through IV inventories, provided previously in
Section 4.1, give an indication as to the amount of documentation that may be required. In some
cases, documentation and reporting requirements are specified by the requestor or statutory
requirement for the inventory. Most inventories will require some form of an inventory report to
document and convey the results of the inventory effort.
An emissions inventory report should include an introduction explaining the background and
purpose for the inventory development, and usually some form of an executive summary to show
summary data and conclusions up-front. The summary of the emissions data should be by some
matrix of pollutant, source type (point, area, mobile, biogenics), and geographic area. Graphics
are useful to illustrate different contributions of source categories to the inventory, and can be
used to clarify various interpretations of the data. Separate discussions to describe the inventory
development procedures and results for all sources should follow.
The following information is typically documented in most inventories:
• Base year (or other applicable time frame) of the inventory;
• The geographic area covered by the inventory;
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• Pollutants and source categories addressed in the inventory;
• Record of all methods used in the inventory preparation;
• Record of all data used in emissions calculations;
• Explanation of all assumptions used;
• Example calculations for each type of methodology used;
• Any demographic data (e.g., population, employment, economic) that was used to
calculate or spatially allocate emissions;
• A listing of all data references;
• Copies of questionnaires or surveys;
• Results of surveys or questionnaires;
• QA/QC checklists;
• QA audit reports; and
• Any other letters, memorandum, or supporting documentation used in the
inventory preparation.
An emissions inventory that is documented according to standardized guidelines enables the
receiving agency to review the inventory in a consistent manner, although it is recognized that
some variability is needed to meet the specific needs of each inventory region. Therefore,
standardization is required for the types of data reported (e.g., many of the items listed above),
but not necessarily for the format in which they are reported. For example, states were given
considerable latitude in the formats for their SIP inventory reports, but minimum information
requirements were identified (EPA, 1991a; EPA, 1991b).
For more information on documenting point and area sources, refer to the EIIP Volumes II and
III respectively. These volumes contain discussions on inventory reporting and documentation
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recommendations from the SIP inventory perspective. In addition, Chapter 2 of Volume VI
discusses the need for comprehensive documentation and reporting from a QA program
standpoint and provides example documentation.
6.2 EXAMPLES OF STANDARDIZED REPORTING FORMAT
One example of standardized reporting procedures are those recommended by the
Intergovernmental Panel on Climate Change (IPCC). The IPCC provides detailed reporting
instructions which consist of step-by-step directions for assembling, documenting, and
transmitting national greenhouse gas inventory data, regardless of the method used to produce the
estimates. The reporting instructions were developed to ensure consistency and comparability
between reports.
Part of the IPCC reporting system is a standard table format (IPCC, 1994) that shows the source
categories included in the inventory and an overview of quality of the estimates (Tables 1.6-1 and
1.6-2), respectively. Emission inventory results and all main assumptions (in summary form) are
transmitted to IPCC. The standard data tables also allow the user to report the inventory at the
level of detail that the data permit. As shown in Table 1.6-2, the IPCC also asks those preparing
greenhouse gas emissions estimates to indicate the completeness, quality, and inclusion of
background information for each emissions estimate.
Another example of standardized reporting format is contained in the EPA's annual report on
emission trends in the United States. Since 1973, EPA has prepared estimates of annual national
emissions in order to assess historic trends in criteria pollutant emissions. These trends are
reported annually in a report entitled National Air Pollutant Emission Trends 1900-(current
year). The standardized emissions reporting structure in the Trends report consists of a "tier"
categorization of source categories. Table 1.6-3 shows the Tier 1 and Tier 2 category levels used
in the report. These tiers represent the highest level of reporting; there are more detailed levels
(Tier 3 and Tier 4) which provide a further breakdown of sources that are more specific to each
pollutant type and emission process.
The examples provided for the IPCC reporting system and for the EPA's Trends report are for
summary and overview purposes and are relatively simple in their presentation. Other inventories
require more abundant and complex reporting formats. The EPA document Example
Documentation Report for 1990 Base Year Ozone and Carbon Monoxide SIP Emissions
Inventories (EPA, 1992c) provides numerous example summary tables and formats for reporting
inventory data collected as part of SIP requirements. The goal of the EPA in providing this
example documentation was to have preparing agencies submit inventory reports that could be
efficiently reviewed that would also facilitate comparison of inventory data. Similar types of
written reporting procedures can be adapted to most other inventory efforts.
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TABLE 1.6-1
IPCC SUMMARY REPORT FOR NATIONAL GREENHOUSE GAS INVENTORIES3
1
o
D
Summary Report for National Greenhouse Gas Inventories (Log)
Greenhouse Gas Source and Sink
Categories
Total National Emissions and Removals
I . All Energy (Fuel Combustion +
Fugitive)
A. Fuel Combustion
1 . Energy & Transformation
Industries
2. Industry (ISIC)
3 . Transport
4. Small Combustion
5. Other
6. Traditional Biomass Burned
for Energy
B. Fugitive Emissions from Fuels
1. Solid Fuels
2. Oil and Natural Gas
2. Industrial Processes
3 . Solvent and Other Products Use
CO2
Emissions
CO2
Removals
CH4
N20
NOX
CO
NMVOC
HFCs
PFCs
o
3
[Tj
^
a Adapted from IPCC (1994).
1
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m
T5
TABLE 1.6-2
CD
\PCC OVERVIEW TABLE FOR NATIONAL GREENHOUSE GAS INVENTORIES'"
Overview Table
Greenhouse Gas Source and Sink
Categories
Total National Emissions and Removals
1. All Energy (Fuel Combustion + Fugitive)
A. Fuel Combustion
1 . Energy & Transformation
Industries
2. Industry (ISIC)
3. Transport
B. Fugitive Emissions from Fuels
1. Solid Fuels
2. Oil and Natural Gas
2. Industrial Processes
3. Solvent and Other Products Use
CO
Estimate
Quality
CH4
Estimate
Quality
2 N20
Estimate
Quality
NOX
Estimate
Quality
CO
Estimate
Quality
NMVOC
Estimate
Quality
Documentation
Footnotes
Notation Key for Overview Table
Estimates
code
PART
ALL
NE
IE
NO
NA
Partly estimated
Partly estimated
Full estimate of all possible sources
Not estimated
Estimated but included elsewhere
Not occurring
Not applicable
Quality
code
H
M
L
Meaning
High Confidence in Estimation
Medium Confidence in Estimation
Low Confidence in Estimation
Documentation
code
H
M
L
Meaning
High (all background information
included)
Medium (some background
information included)
Low (only emission estimates
included)
1
o
D
O
3
"Adapted from IPCC (1994).
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TABLE 1.6-3
TIER 1 AND TIER 2 SOURCE CATEGORIES3
Tier 1
Tier 2
FUEL COMBUSTION-ELECTRIC UTILITIES
Coal
Oil
Gas
Other
Internal Combustion
FUEL COMBUSTION-INDUSTRIAL
Coal
Oil
Gas
Other
Internal Combustion
FUEL COMBUSTION-OTHER
Commercial/Industrial Coal
Commercial/Industrial Oil
Commercial/Industrial Gas
Misc. Fuel Combustion (except residential)
Residential Wood
Residential Other
CHEMICAL & ALLIED PRODUCT MFG.
Organic Chemical Mfg.
Inorganic Chemical Mfg.
Polymer & Resin Mfg.
Agricultural Chemical Mfg.
Paint, Varnish, Lacquer, Enamel Mfg.
Pharmaceutical Mfg.
Other Chemical Mfg.
METALS PROCESSING
Nonferrous
Ferrous
Not elsewhere classified (NEC)
PETROLEUM & RELATED INDUSTRIES
Oil & Gas Production
Petroleum Refineries & Related Industries
Asphalt Manufacturing
OTHER INDUSTRIAL PROCESSES
Agriculture, Food, & Kindred Products
Textiles, Leather, & Apparel Products
Wood, Pulp & Paper, & Publishing Products
Rubber & Miscellaneous Plastic Products
Mineral Products
Machinery Products
Electronic Equipment
Transportation Equipment
Construction
Miscellaneous Industrial Processes
1.6-6
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TABLE 1.6.3
(CONTINUED)
Tierl
Tier 2
SOLVENT UTILIZATION
Degreasing
Graphic Arts
Dry Cleaning
Surface Coating
Other Industrial
Nonindustrial
Solvent Utilization (NEC)
STORAGE & TRANSPORT
Bulk Terminals & Plants
Petroleum & Petroleum Product Storage
Petroleum & Petroleum Product Transport
Service Stations: Stage I
Service Stations: Stage n
Service Stations: Breathing & Emptying
Organic Chemical Storage
Organic Chemical Transport
Inorganic Chemical Storage
Inorganic Chemical Transport
Bulk Materials Storage
Bulk Materials Transport
WASTE DISPOSAL & RECYCLING
Incineration
Open Burning
Publicly Owned Treatment Works
Industrial Waste Water
Treatment Storage and Disposal Facility
Landfills
Other
HIGHWAY VEHICLES
Light-Duty Gas Vehicles & Motorcycles
Light-Duty Gas Trucks
Heavy-Duty Gas Vehicles
Diesels
OFF-HIGHWAY
Off-highway Gasoline
Off-highway Diesel
Aircraft
Marine Vessels
Railroads
NATURAL SOURCES
Biogenic
Geogenic
Miscellaneous (lightning, freshwater, saltwater)
MISCELLANEOUS
Agriculture & Forestry
Other Combustion (Forest Fires)
Catastrophic/accidental Releases
Repair Shops
Health Services
Cooling Towers
Fugitive Dust
aAdapted from EPA (1994b).
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6.3 ELECTRONIC REPORTING OF DATA
Sharing of emissions data is essential for urban and regional air quality modeling exercises that
cross state boundaries, for regional and national regulatory impact and other policy analyses, for
scientific research efforts, and for informing the public. In order to facilitate this process, the EIIP
DMC is currently working on the completion of the Data Model to allow transfer of electronic
data from the inventory preparer to multiple end users.
The EIIP Data Model is currently focused on the emission inventory data needed to support air
quality modeling. While the initial scope covers the inventory data compiled for the SIP
attainment demonstrations (as well as base year inventories, annual point source reporting, and
trends analysis), the Data Model does not yet address some of the more detailed facility-level
information needed, for example, for permit processing. Additional phases of development will
need to be conducted by the EIIP to address these related data areas.
Examples of the application of electronic reporting techniques is evident in the different options
available to states to report emissions data as part of their annual and periodic reporting
requirements as prescribed under Sections 110(a)(2)(F) and 182(a)(3)(A) of the CAA as amended
in 1990, respectively. Annual reporting requirements under Section 110(a)(2)(F) require
reporting of criteria air pollutants for all areas under the general SIP requirements of Section 110.
Section 182(a)(3)(A) requires that States with ozone nonattainment areas submit periodic
inventories of VOC, NOX, and CO emissions for point sources, area sources, mobile sources, and
biogenic sources. Electronic reporting facilitates access by the inventory community to the
wealth of emissions data created by these efforts.
Four basic options currently exist for electronic data reporting for the examples listed above.
• EIIP Data Model transfer format;
• EPA National Emissions Trends (NET) Database format;
• Aerometric Information Retrieval System (AIRS) AFS (Facility Subsystem)
format; and
• State-specific format.
Two of the data reporting options discussed here, the EIIP/EDI format and the NET Database
format, use the data element relationships defined in the EIIP Data Model. The EIIP has
developed a data transfer format using existing EDI standards. The EDI data exchange standard
is a nonproprietary standard created and maintained by the American National Standards Institute
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(ANSI). The EIIP/EDI format can provide a common data exchange format for federal, state and
local government agencies, and eventually industry, to exchange emissions inventory information
electronically using a single data transfer format.
Another data transfer option for the annual reporting requirements is to use the EPA NET
Database Format. The NET database will be compatible with the EIIP Data Model, and include
the data elements and data relationships as they are defined in the EIIP Data Model. The new
NET database will also be used in the EIIP EDI data transfer demonstration described above.
The AIRS format has been used for electronic reporting for previous state-submitted inventories
and is still the primary inventory data storage vehicle for several states. Although using the AIRS
format is a feasible and valid way to make an electronic inventory submittal, this method of
reporting has some limitations. The chief constraint is that only point source information can be
submitted in the AIRS format. Information about AIRS can be found on the OAQPS CHIEF
BBS, or through the TTN 2000 Internet web site, described earlier in this chapter.
Other reporting formats for inventory data include electronic files in a state-specified format and
may consist of database, spreadsheet, or flat ASCII files. If a state intends to submit inventory
data in this form as part of their reporting requirements for annual or periodic inventories, the
EPA's EFIG should be contacted ahead of time to confirm these procedures.
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REFERENCES
EPA. 1986. Quality Assurance and Quality Control Plan for the NAPAP 1985 Emission
Inventory. U.S. Environmental Protection Agency, Air and Energy Engineering Research
Laboratory, EPA-600/8-86-025, Research Triangle Park, North Carolina.
EPA. 1988. Guidance for the Preparation of Quality Assurance Plans for O3/CO SIP Emission
Inventories. U.S. Environmental Protection Agency, Office of Air Quality Planning and
Standards, EPA-450/4-88-023. Research Triangle Park, North Carolina.
EPA. 1989. Quality Assurance Program for Post-1987 Ozone and Carbon Monoxide State
Implementation Plan Emission Inventories. U.S. Environmental Protection Agency, Office of Air
Quality Planning and Standards, EPA-450/4-89-004. Research Triangle Park, North Carolina.
EPA. 1991 a. Emission Inventory Requirements for Ozone State Implementation Plans. U. S.
Environmental Protection Agency, Office of Air Quality Planning and Standards,
EPA-450/4-91-010. Research Triangle Park, North Carolina.
EPA. 1991 b. Emission Inventory Requirements for Carbon Monoxide State Implementation
Plans. U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards,
EPA-450/4-91-011. Research Triangle Park, North Carolina.
EPA. 1992a. Procedures for Emission Inventory Preparation. Volume IV: Mobile Sources.
U.S. Environmental Protection Agency, Office of Air and Radiation, Office of Mobile Sources
and Office of Air Quality Planning and Standards, Emission Planning and Strategies Division and
Technical Support Division, EPA-450/4-81-026d (Revised). Ann Arbor, Michigan, and
Research Triangle Park, North Carolina.
EPA. 1992b. Example Documentation Report for 1990 Base Year Ozone and Carbon Monoxide
State Implementation Plan Emission Inventories. U.S. Environmental Protection Agency, Office
of Air Quality Planning and Standards, EPA-450/4-92-007. Research Triangle Park, North
Carolina.
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EPA. 1992c. Example Documentation Report for 1990 Base Year Ozone and Carbon Monoxide
State Implementation Plan Emission Inventories, U.S. Environmental Protection Agency, Office
of Air Quality Planning and Standards, EPA-450/4-92-007. Research Triangle Park, North
Carolina.
EPA. 1994a. AEERL Quality Assurance Procedures Manual for Contractors and Financial
Assistance Recipients. U.S. Environmental Protection Agency, Air and Energy Engineering
Research Laboratory. Research Triangle Park, North Carolina.
EPA. 1994b. National Air Pollutant Emission Trends, 1900-1993. U.S. Environmental
Protection Agency, Office of Air Quality Planning and Standards. Research Triangle Park, North
Carolina.
EPA. 1995. Roles and Responsibilities of Government Agencies in the Development of
Emission Inventories. Report prepared by Wiley Barbour, Radian Corporation, for J. David
Mobley, Emission Inventory Improvement Program, Government Interactions Committee.
EPA. 1995-1996. Compilation of Air Pollutant Emission Factors, Volume I: Stationary Point
and Area Sources, Fifth Edition and Supplements, AP-42. U.S. Environmental Protection
Agency, Office of Air Quality Planning and Standards. Research Triangle Park, North Carolina.
IPCC (1994). Greenhouse Gas Inventory Reporting Instructions. IPCC Draft Guidelines for
National Greenhouse Gas Inventories, Volume !.
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8
GLOSSARY
8.1 POINT SOURCES
Actual Emissions are the actual rate of emissions of a pollutant from an emissions unit calculated
using the unit's actual operating hours, production rates, and types of materials processed, stored,
or combusted during the selected time period.
Allowable Emissions are the emissions rate that represents a limit on the emissions that can occur
from an emissions unit. This limit may be based on a federal, state, or local regulatory emission
limit determined from state or local regulations and/or 40 Code of Federal Regulations (CFR)
Parts 60, 61, and 63.
Ambient Standards limit the concentration of a given pollutant in the ambient air. Ambient
standards are not emissions limitations on sources, but usually result in such limits being placed on
source operation as part of a control strategy to achieve or maintain an ambient standard.
Area Sources are smaller sources that do not qualify as point sources under the relevant emissions
cutoffs. Area sources encompass more widespread sources that may be abundant, but that,
individually, release small amounts of a given pollutant. These are sources for which emissions
are estimated as a group rather than individually. Examples typically include dry cleaners,
residential wood heating, auto body painting, and consumer solvent use. Area sources generally
are not required to submit individual emissions estimates.
Carbon Monoxide (CO) is a colorless, odorless gas that depletes the oxygen-carrying capacity of
blood. Major sources of CO emissions include industrial boilers, incinerators, and motor vehicles.
Class I Substances as defined in Title VT of the Clean Air Act Amendments (CAAA) include
chlorofluorocarbons (CFCs), halons, carbon tetrachloride, and methyl chloroform. According to
the CAAA, all of these compounds must be phased out of production by the year 2000 with the
exception of methyl chloroform, which must be phased out of production by the year 2002.
Provisions are also made that allow for acceleration of this phaseout.
Class II Substances as defined in Title VT of the Clean Air Act Amendments (CAAA) include
hydrochlorofluorocarbons (HCFCs). These substances must be phased out of production by the
year 2015.
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Continuous Emissions Monitoring (CEM) is any monitoring effort that "continuously" measures
(i.e., measures with very short averaging times) and records emissions. In addition to measuring
and recording actual emissions during the time of monitor operation, CEM data can be used to
estimate emissions for different operating periods and longer averaging times.
Criteria Pollutant refers to a pollutant for which a National Ambient Air Quality Standard
(NAAQS) has been set. Criteria pollutants are carbon monoxide (CO), lead (Pb), nitrogen oxides
(NOX), Ozone (measured as volatile organic compounds [VOCs]), particulate matter of
aerodynamic diameter less than or equal to 10 micrometers (PM10), and sulfur dioxide (SO2).
Design Standards impose certain hardware requirements. For example, a design standard might
require that leaks from compressors be collected and diverted to a control device. Design
standards are typically used when an emissions limit is not feasible.
Emission Concentration Standards limit the mass emissions of a pollutant per volume of air.
Emission concentration standards are expressed in terms such as grams per dry standard cubic
meter (g/dscm) or other similar units.
Emission Factors are ratios that relate emissions of a pollutant to an activity level at a plant that
can be easily measured, such as an amount of material processed, or an amount of fuel used.
Given an emission factor and a known activity level, a simple multiplication yields an estimate of
the emissions. Emission factors are developed from separate facilities within an industry category,
so they represent typical values for an industry, but do not necessarily represent a specific source.
Published emission factors are available in numerous sources.
Emissions Reduction Standards limit the amount of current emissions relative to the amount of
emissions before application of a pollution control measure. For example, an emission reduction
standard may require a source to reduce, within a specified time, its emissions to 50 percent of the
present value.
Emission Standards are a general type of standard that limit the mass of a pollutant
that may be emitted by a source. The most straightforward emissions standard is a simple
limitation on mass of pollutant per unit time (e.g., pounds of pollutant per hour).
Engineering Estimate is a term commonly applied to the best approximation that can be made
when the specific emission estimation techniques such as stack testing, material balance, or
emission factor age are not possible. This estimation is usually made by an engineer familiar with
the specific process, and is based on whatever knowledge may be available.
Equipment Standards require a specific type of equipment to be used in certain processes.
Equipment standards are typically used when an emissions limit is not feasible.
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Fugitive Emissions are emissions from other sources that are technically infeasible to collect and
control (e.g., storage piles, wastewater retention ponds, etc.).
Hazardous Air Pollutants (HAPs) are listed in Section 112(b) of the 1990 Clean Air Act
Amendments (CAAA). These pollutants are emitted in smaller quantities than criteria pollutants
but may be reasonably anticipated to cause cancer, developmental effects, reproductive
dysfunctions, neurological disorders, inheritable gene mutations, or other chronically or acutely
toxic effects in humans. The CAAA specifies an initial list of 189 HAPs to be subject to further
regulation. The list of HAPs includes relatively common pollutants such as formaldehyde,
chlorine, methanol, and asbestos, as well as numerous less-common substances. Pollutants may,
under certain circumstances, be added to or deleted from the list.
Lead (Pb) is an element that causes several types of developmental effects in children including
anemia, neurobehavioral alterations, and metabolic alterations. Lead is emitted from industries
such as battery manufacturing, lead smelters, and incineration. Although regulated in highway
fuels, lead may also be emitted from unregulated off-highway mobile sources.
Material Balance or Mass Balance is a method for estimating emissions that attempts to account
for all the inputs and outputs of a given pollutant. If inputs of a material to a given process are
known and all outputs except for air emissions can be reasonably well quantified, then the
remainder can be assumed to be an estimate of the amount lost to the atmosphere for the process.
Maximum Achievable Control Technology (MACT) Standards in addition to National
Emissions Standards for Hazardous Air Pollutants (NESHAP), are promulgated under
Section 112 of the Clean Air Act Amendments (CAAA). Technically NESHAP and MACT
standards are separate programs. MACT standards differ from older NESHAPs because MACT
standards are mandated by law to require the maximum achievable control technology, while
NESHAPs were based on risks to public health. MACT standards are source category-specific,
and each standard covers all the pollutants listed in Section 112 of the CAAA that are emitted by
that source category. The first MACT standard promulgated (for the Synthetic Organic Chemical
Manufacturing Industries) was originally developed as a NESHAP and is still referred to as the
Hazardous Organic NESHAP (HON).
Means of Release to the Atmosphere is the mechanism by which emissions enter the atmosphere.
Environmental agencies usually classify release mechanisms into three categories: process
emissions, fugitive emissions, and process fugitive emissions. This characteristic of an emission
source is important because emission factors and other estimation methods are specific to the type
of release.
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Mobile Sources include all nonstationary sources, such as automobiles, trucks, buses,
motorcycles, aircraft, trains, construction and farm equipment, and other nonroad engines and
vehicles.
National Ambient Air Quality Standards (NAAQS) are the main ambient standards for the
following six criteria pollutants: carbon monoxide (CO), lead (Pb), nitrogen oxides (NOX), sulfur
oxides (SOX), volatile organic compounds (VOCs), and paniculate matter of aerodynamic
diameter less than or equal to 10 micrometers (PM10).
National Emissions Standards for Hazardous Air Pollutants (NESHAP) are a class of
standards limiting emissions of HAPs and are based on risk to public health. The common usage
of NESHAP actually refers to two different sets of standards, which are pollutant or source
category-specific. The NESHAP, are published in 40 Code of Federal Regulations
(CFR)Part61.
New Source Performance Standards (NSPS) are promulgated for criteria, hazardous, and other
pollutant emissions from new, modified, or reconstructed sources that the U.S. Environmental
Protection Agency (EPA) determines contribute significantly to air pollution. These are typically
emission standards, but may be expressed in other forms such as concentration and opacity. The
NSPS are published in 40 Code of Federal Regulations (CFR) Part 60.
Nitrogen Oxides (NOX) are a class of compounds that are respiratory irritants and that react with
volatile organic compounds (VOCs) to form Ozone (O3). The primary combustion product of
nitrogen is nitrogen dioxide (NO2). However, several other nitrogen compounds are usually
emitted at the same time (nitric oxide [NO], nitrous oxide [N2O], etc.), and these may or may not
be distinguishable in available test data. They are usually in a rapid state of flux, with NO2 being,
in the short term, the ultimate product emitted or formed shortly downstream of the stack. The
convention followed in emission factor documents is to report the distinctions wherever possible,
but to report total NOX on the basis of the molecular weight of NO2. NOX compounds are also
precursors to acid rain. Motor vehicles, power plants, and other stationary combustion facilities
emit large quantities of NOX.
Opacity Standards limit the opacity (in units of percent opacity) of the pollutant discharge rather
than the mass of pollutant.
Operational Standards impose some requirements on the routine operation of the unit. Such
standards include maintenance requirements or operator training certification requirements.
Operational standards are typically used when an emission limit is not feasible.
Ozone (O3) is a colorless gas that damages lungs and can damage materials and vegetation. It is
the primary constituent of smog, and is formed primarily when nitrogen oxides (NOX) and volatile
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organic compounds (VOCs) react in the presence of sunlight. It is also emitted in insignificant
quantities from motor vehicles, industrial boilers, and other minor sources.
Particulate Matter of aerodynamic diameter less than or equal to 10 micrometers (PM10) is a
measure of small solid matter suspended in the atmosphere. Small particles can penetrate deeply
into the lung where they can cause respiratory problems. Emissions of PM10 are significant from
fugitive dust, power plants, commercial boilers, metallurgical industries, mineral industries, forest
and residential fires, and motor vehicles.
Particulate Matter of aerodynamic diameter less than or equal to 2.5 micrometers (PM25) is a
measure of fine particles of particulate matter that come from fuel combustion, agricultural
burning, woodstoves, etc. On November 27, 1996 the U.S. Environmental Protection Agency
proposed to revise the current primary (health-based) PM standards by adding a new annual PM2 5
standard.
Plant Level Emissions are consolidated for an entire plant or facility. A plant may contain one or
many pollutant-emitting sources.
Plant Level Reporting is generally required if total emissions from a plant (which may be
composed of numerous individual emission points) meet the point source cutoff. These data can
be used by the state to conduct a detailed estimate of emissions from that plant. The plant level
reporting used by most air pollution control agencies generally requires that the facility provide
data that apply to the facility as a whole. Such data include number of employees and the
Standard Industrial Classification (SIC) code designation for the plant. A plant usually has only
one SIC code denoting the principal economic activity of the facility. For the purpose of clearly
identifying and tracking emissions data, each plant is generally assigned a plant (alternatively,
"facility") name and number. The plant is also identified by geographic or jurisdictional
descriptors such as air quality control region, county, address, and Universal Transverse Mercator
(UTM) grid coordinates (or latitude/longitude) that identify a coterminous location. An owner or
operator engaged in one or more related activities is also identified. In some cases, plantwide
emissions may be reported at the plant level.
Point Level Emissions typically represent single stacks or vents individually large enough to be
considered point sources.
Point Level Reporting includes specific data for individual emission points (typically stacks).
These data are more detailed than that submitted in Plant Level Reporting and may include
emission-related and modeling information such as stack height of the release point, diameter of
the stack, emission rate, method of determination, fugitive emissions, gas exit velocity from a
stack, gas temperature, and operating schedule. Source identification information, as previously
described under Plant Level Reporting, is usually also required at the point level to ensure that
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emission data for a single plant remain clearly identified. Regulatory agencies generally maintain
individual emission-related records at the point level.
Point Sources are large, stationary, identifiable sources of emissions that release pollutants into
the atmosphere. Sources are often defined by state or local air regulatory agencies as point
sources when they annually emit more than a specified amount of a given pollutant, and how state
and local agencies define point sources can vary. Point sources are typically large manufacturing
or production plants. They typically include both confined "stack" emission points as well as
individual unconfmed "fugitive" emission sources.
Within a given point source, there may be several emission points that make up the point source.
Emissions point refers to a specific stack, vent, or other discrete point of pollution release. This
term should not be confused with point source, which is a regulatory distinction from area and
mobile sources. The characterization of point sources into multiple emissions points is useful for
allowing more detailed reporting of emissions information.
For point sources, the emission estimate reporting system used by most state and local air
regulatory agencies groups emission sources into one of three categories and maintains emission-
related data in a different format for each. The three categories are plant level, point level, and
process or segment level.
Potential Emissions are the potential rate of emissions of a pollutant from an emissions unit
calculated using the unit's maximum design capacity. Potential emissions are a function of the
unit's physical size and operational capabilities.
It is important to note that annual potential emissions from a unit are not necessarily the product
of 8760 hours per year times the hourly potential emissions. For most processes, the operation of
one piece of equipment is limited in some way by the operation of another piece of equipment
upstream or downstream. For example, consider a batch process involving vessels X, Y, and Z in
series (i.e., the output from Vessel X is the feed to Vessel Y, and the output from Vessel Y is the
feed to Vessel Z) where the residence time for each vessel is different. In this process, Vessel Y
may not operate 8760 hours per year because either the output from Vessel X is not feeding
Vessel Y at all times or Vessel Z may not always be available to accept the output from Vessel Y.
It is also possible for the emission rate to vary over time. For instance, if a reaction requires
6 hours to reach completion, the emissions from the reaction vessel during the first hour will be
different than those during the last hour. Thus, the highest hourly emission rate is not sustained
during the entire cycle or for the entire year.
Process-based Emission Standards limit the mass emissions per unit of production. These
standards may limit mass emissions per unit of material processed or mass emissions per unit of
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energy used. As process rate increases (e.g., an increase in tons of ore processed per hour), the
allowable emissions increase (e.g., an increase in pounds of pollutant per hour).
Process Emissions are emissions from sources where an enclosure, collection system, ducting
system, and/or stack (with or without an emission control device) is in place for a process.
Process emissions represent emissions from process equipment (other than leaks) where the
emissions can be captured and directed through a controlled or uncontrolled stack for release into
the atmosphere.
Process Fugitive Emissions occur as leaks from process equipment including compressors, pump
seals, valves, flanges, product sampling systems, pressure relief devices, and open-ended lines.
Emissions from the process that are not caught by the capture system are also classified as process
fugitive emissions.
Process or Segment Level Emissions usually represent a single process or unit of operation.
Process or Segment Level Reporting involves each process within a plant being identified by a
U.S. Environmental Protection Agency (EPA) source classification code (SCC). For point
sources, reporting guidelines may require that a plant identify, for each process or operation
(designated by SCC), the periods of process operation (daily, weekly, monthly, annually);
operating rate data including actual, maximum, and design operating rate or capacity; fuel use and
fuel property data (ash, sulfur, trace elements, heat content, etc.); identification of all pollution
control equipment and their associated control efficiencies (measured or design); and emissions
rates. Source identification information, as previously described under Plant Level Reporting, is
usually also required at the process level to ensure that emissions data for a single plant are clearly
identified.
Process-specific Empirical Relationships are similar to emission factors in that they relate
emissions to easily identifiable process parameters. However, these relationships are represented
by more detailed equations that relate emissions to several variables at once, rather than a simple
ratio. An example is the estimate for volatile organic compound (VOC) emissions from storage
tanks that is based on tank size, air temperature, and vapor pressure.
Reported Emissions are those emission estimates that are submitted to a regulatory agency.
Emissions inventories can be used for a variety of purposes such as State Implementation Plan
(SIP) base year inventories, environmental compliance audits, air quality rule applicability, and
reporting information in an air quality permit application. Emissions can be reported on an actual,
potential, or maximum basis. Many state and local air pollution control agencies have rules and
regulations that define an allowable emission value for a particular piece of equipment. Because
of this, a facility should first define the purpose of the inventory and then choose the appropriate
means of reporting emissions to the regulatory agency. For example, SIP base year inventories
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for point sources would contain actual emissions. However, regulatory applicability and air
quality permit applications can require that actual, allowable, and potential emissions be reported.
Source Tests are short-term tests used to collect emissions data that can then be extrapolated to
estimate long-term emissions from the same or similar sources. Uncertainties arise when source
test results are used to estimate emissions under process conditions that differ from those under
which the test was performed.
Stratospheric Ozone-depleting Compounds are chlorofluorocarbons (CFCs), halons, carbon
tetrachloride, methyl chloroform, and hydrochlorofluorocarbons (HCFCs). These pollutants are
regulated by Title VI of the Clean Air Act Amendments (CAAA) because they may destroy
stratospheric Ozone. Title VT is primarily designed to limit the manufacture of these materials,
not their use. The pollutants are divided into two classes (Class I and Class II) based on the dates
by which their manufacture must be discontinued. Methods to estimate emissions of Ozone-
depleting compounds are not discussed in Emission Inventory Improvement Program (EIIP)
documents. Information on emissions of Ozone-depleting compounds can be obtained from the
U.S. Environmental Protection Agency (EPA), Office of Atmospheric and Indoor Air Programs,
Global Climate Change Division, located at EPA Headquarters in Washington, D.C.
Sulfur Oxides (SOX) are a class of colorless, pungent gases that are respiratory irritants and
precursors to acid rain. Sulfur oxides are emitted from various combustion or incineration
sources, particularly from coal combustion.
Volatile Organic Compounds (VOCs) react with nitrogen oxides (NOX) in the atmosphere to
form Ozone (O3). Although not criteria pollutants, VOC emissions are regulated under criteria
pollutant programs because they are Ozone precursors. Large amounts of VOCs are emitted
from fuel distribution, chemical manufacturing, motor vehicles, and a wide variety of industrial,
commercial, and consumer solvent uses.
The use of certain photochemical models requires estimation of methane, ethane, and several
other less photochemically reactive compounds and particulates. While not regulated as VOCs,
these compounds may need to be estimated for certain modeling inventories or to meet certain
state inventory requirements. For this reason, the term total organic compounds (TOCs) is used
to refer to this broader class of chemicals.
Work Practice Standards require some action during the routine operation of the unit. For
example, volatile organic compound (VOC) monitoring of a compressor might be required on a
quarterly basis to ensure no leaks are occurring. Work practice standards are typically used when
an emission limit is not feasible.
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8.2 AREA SOURCES
Activity Level/Factor is a measurable factor that is directly or indirectly related to the emissions
of a process. An emission estimate is calculated by multiplying an activity level by an emission
factor. The activity level is either directly related to the amount of emissions (as in the case of the
amount of fuel used in a combustion process), or is a more easily measured surrogate, such as
population for consumer product usage.
Area Sources are smaller sources that do not qualify as point sources under the relevant emissions
cutoffs. Area sources encompass more widespread sources that may be abundant, but that,
individually, release small amounts of a given pollutant. These are sources for which emissions
are estimated as a group rather than individually. Examples typically include dry cleaners,
residential wood heating, auto body painting, and consumer solvent use. Area sources generally
are not required to submit individual emissions estimates.
Biogenic Sources are biological sources of emissions such as trees, agricultural crops, or
microbial activity in soils or water. This term is sometimes used to describe any natural emission
source.
Carbon Monoxide (CO) is a colorless, odorless gas that depletes the oxygen-carrying capacity of
blood. Major sources of CO emissions include industrial boilers, incinerators, and motor vehicles.
Control Efficiency (CE) is the emission reduction efficiency, and is a percentage value
representing the amount of a source category's emissions that are controlled by a control device,
process change, or reformulation.
Double Counting means estimation and counting of estimated emissions twice in an inventory.
Area source inventories are at risk of double counting emissions from two sources because of
point and area source overlap and overlap between two area sources.
Emission Factor is a ratio between the amount of pollution produced and an activity level. Given
an emission factor and a known activity level, a simple multiplication yields an estimate of the
emissions. See Activity Level/Factor, and the Point Source definition of Emission Factor.
Emission Inventory is a listing, by source, of the amount of air pollutants discharged into the
atmosphere of a community; used to establish emission standards.
Growth Factors are surrogate indicators that predict the proportional change in the activity level
or emissions for a particular emissions source.
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Inventory Area is generally defined by political boundaries such as county and state boundaries,
where the jurisdictions that are included in an inventory area make up an air basin or experience
common air problems. The pollutant or the type of air pollution inventory will determine the
exact geographic area that will be covered.
Material Balance or Mass Balance is a method for estimating emissions that attempts to account
for all the inputs and outputs of a given pollutant. If inputs of a material to a given process are
known and all outputs except for air emissions can be reasonably well quantified, then the
remainder can be assumed to be an estimate of the amount lost to the atmosphere for the process.
Mathematical Emission Model is an emission estimation technique that uses a mathematical
model to estimate emissions. A very simple mathematical model is an emission factor and an
activity level. A more complex model may involve multiple parameters and iterations in the
calculation process. A mathematical model may be used by inventory preparers as an equation or
as a computer program.
Mobile Sources include all nonstationary sources, such as automobiles, trucks, buses,
motorcycles, aircraft, trains, construction and farm equipment, and other nonroad engines and
vehicles.
Nitrogen Oxides (NOX) are a class of compounds that are respiratory irritants and that react with
volatile organic compounds (VOCs) to form Ozone (O3). The primary combustion product of
nitrogen is nitrogen dioxide (NO2). However, several other nitrogen compounds are usually
emitted at the same time (nitric oxide [NO], nitrous oxide [N2O], etc.), and these may or may not
be distinguishable in available test data. They are usually in a rapid state of flux, with NO2 being,
in the short term, the ultimate product emitted or formed shortly downstream of the stack. The
convention followed in emission factor documents is to report the distinctions wherever possible,
but to report total NOX on the basis of the molecular weight of NO2. NOX compounds are also
precursors to acid rain. Motor vehicles, power plants, and other stationary combustion facilities
emit large quantities of NOX.
Nonmethane Hydrocarbons (NMHCs) are a class of compounds that includes a wide range of
specific organic chemical substances including reactive volatile organic compounds (VOCs),
which form Ozone, a greenhouse gas, in the troposphere. A major local and regional air
pollutant, they cause significant health and environmental damage.
Ozone (O3) is a colorless gas that damages lungs and can damage materials and vegetation. It is
the primary constituent of smog, and is formed primarily when nitrogen oxides (NOX) and volatile
organic compounds (VOCs) react in the presence of sunlight. It is also emitted in insignificant
quantities from motor vehicles, industrial boilers, and other minor sources.
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Point Sources are emission units that are inventoried individually, and in much greater detail, in
comparison to area sources. The distinction between point and area sources is usually defined by
a cutoff level, typically based on emissions. See the following terms in the Point Sources
Glossary: Plant Level Emissions, Plant Level Reporting, Point Level Emissions, and Point Level
Reporting.
Projection Inventory is an inventory that is prepared to predict future emissions levels using base
year emissions, growth factors, and current and future controls.
Quality Assurance (QA) is a process that involves both the inventory team and external reviewers
to insure the overall quality of the inventory.
Quality Control (QC) comprises the activities undertaken by all members of the inventory team
during the inventory preparation that will result in the correction of specific problems such as
mistaken assumptions, lost or uncollected data, and calculation and data entry errors.
Rule Effectiveness (RE) is the measure of the ability of the regulatory program to achieve all
emission reductions possible, which reflects the assumption that regulations are typically not
100 percent effective. RE is used as an adjustment to the control efficiency. See Control
Efficiency and Rule Penetration.
Rule Penetration (RP) is the percentage of an area source category that is covered by an
applicable regulation.
Standard Industrial Classification (SIC) Codes are codes defined by the U.S. Department of
Commerce that classify businesses by products or services. SICs are the Federal standard for
classifying establishment-based statistics..
Spatial Allocation entails assignment of activity levels or emission estimates to a smaller or larger
geographic area than the area for which the activity level or emission estimate was prepared.
Allocation usually requires the identification of a surrogate indicator that can be used for scaling.
State Implementation Plan (SIP) Inventories are inventories prepared to meet the requirements
of a state plan approved by the U.S. Environmental Protection Agency for the establishment,
regulation, and enforcement of air pollution standards.
Surveys are a method to collect inventory data using telephone or written questionnaires that are
answered by manufacturers or suppliers of products, or by representatives at the facilities or sites
where the emitting processes take place. An area source survey may also include review and data
collection from existing air pollution permits within an agency. Surveys for area source
inventories usually survey a subset of the population of sources.
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Temporal Adjustments are adjustments to an emission estimate to reflect the time period desired
for the inventory. Adjustments may need to be made to reflect differences in the usage level for a
season, a certain day of the week, or time of day. Adjustments may also need to be made to
reflect differences in temperature or other climatological variations that affect emissions.
Volatile Organic Compounds (VOCs) react with nitrogen oxides (NOX) in the atmosphere to
form Ozone (O3). Although not criteria pollutants, VOC emissions are regulated under criteria
pollutant programs because they are Ozone precursors. Large amounts of VOCs are emitted
from fuel distribution, chemical manufacturing, motor vehicles, and a wide variety of industrial,
commercial, and consumer solvent uses.
The use of certain photochemical models requires estimation of methane, ethane, and several
other less photochemically reactive compounds and particulates. While not regulated as VOCs,
these compounds may need to be estimated for certain modeling inventories or to meet certain
state inventory requirements. For this reason, the term total organic compounds (TOCs) is used
to refer to this broader class of chemicals.
8.3 MOBILE SOURCES
Highway Performance Monitoring System (HPMS) is a program developed by the U.S.
Department of Transportation Federal Flighway Administration in the mid-1970s to collect and
report information on the nation's highways.
MOBILEX.Xis the U.S. Environmental Protection Agency's emission factor model that helps
analysts in estimating motor vehicle contributions to the local emissions inventory and is designed
to account for the effect of numerous vehicle parameters on the volume of pollutants emitted.
Latest versions are MOBILESa and MOBILESb.
Vehicle Miles Traveled (VMT) is an expression of vehicle activity that is used with emission
factors, typically in units of grams per mile of travel. Because VMT does not directly correlate to
emissions that occur while the vehicle is not moving, these nonmoving emissions are incorporated
into the U.S. Environmental Protection Agency's MOBILE model emission factors.
Travel Demand Model (TDM) is a mathematical model used to assess the effects of growth on a
highway network and allows transportation analysts to evaluate the improvements that are
needed. From the perspective of air quality, important products of these models are estimates of
vehicle miles traveled and speed on each of the roadway links coded in the highway network.
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Federal Test Procedure (FTP) is a standardized procedure developed by the U.S. Environmental
Protection Agency to measure emissions rates from motor vehicles. The FTP is a chassis
dynamometer test conducted using a standardized driving cycle under standardized conditions.
Operating Modes include the three vehicle modes of operation represented by emission factors
based on the federal test procedure driving cycle. The three modes of operation are: cold start,
hot start, and hot stabilized.
Cold Start is the operating mode that reflects conditions experienced at the beginning of a
trip when the engine and the emission control system begin operation at ambient
temperature and are not performing at optimum levels.
Hot Start is the operating mode that reflects the condition of an engine that has been
restarted after being turned off for 10 minutes and, therefore, has not cooled to ambient
conditions.
Hot Stabilized is the operating modes that reflects the condition of the engine when the
vehicle has been in continuous operation long enough for all systems to have attained
stable operating temperatures.
Vehicle Classes are designated categories of vehicles registered to use the public roadways, and
include automobiles, trucks, buses, and motorcycles. The U.S. Environmental Protection
Agency's MOBILE model contains eight vehicle classes for which emission factors can be
produced.
8.4 BIOGENIC SOURCES
Anthropogenic Emission Sources are emission sources that depend on human behavior.
Included in this group are emissions from agricultural operations, biomass burning, and emissions
from microbial activity during waste treatment.
Biogenic Sources are biological sources of emissions such as trees, agricultural crops, or
microbial activity in soils or water. This term is sometimes used to describe any natural emission
source.
Carbon Dioxide (CO2) is a colorless, odorless, nonpoisonous gas that results from fossil fuel
combustion and is normally a part of the ambient air.
Cloud Cover is the thickness, level, and percentage of load per level of clouds covering the sky.
See Sky Cover.
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Emission Factor is a ratio of the emissions per unit of activity per unit of time. When estimating
biogenic volatile organic compound (VOC) emissions, the emission factor will be based on the
amount of vegetation biomass. See Emission Rate.
Emission Flux is the emissions per unit of area per unit of time for a particular vegetation type
(in the case of biogenic volatile organic compound [VOC] emissions) or land use type (in the case
of biogenic nitric oxide [NO] emissions).
Emission Rate is the emissions per unit of time for a particular source type, such as a vegetation
type, and for a particular chemical species. When calculating biogenic emissions, the emission
rate is dependant on the vegetation type emission factor, the amount of biomass, and
environmental factors accounting for solar radiation and leaf temperature.
Geogenic Emission Sources result from geological activity. Sources include volcanoes,
fumaroles, and natural seeps of oil or natural gas.
Geographic Information System (GIS) is a computer-based information system that allows for
storage and manipulation of spatially related data.
Greenhouse Gases that occur naturally include water vapor, carbon dioxide (CO2), methane
(CH4), nitrous oxide (N2O), and Ozone (O3). Chlorofluorocarbons (CFCs) (a family of human-
made compounds), its substitute hydrofluorocarbons (HFCs), and other compounds such as
perfluorinated carbons (PFCs) are also greenhouse gases.
Land Use Data describe the predominant vegetative cover, type of water body, or anthropogenic
use (buildings, parking lots, etc.) of land for areas of a defined scale.
Methane (CH4) is a colorless, nonpoisonous flammable gas created by anaerobic decomposition
of organic compounds; considered a greenhouse gas pollutant.
Natural Emission Sources are nonanthropogenic sources of emissions that include biogenic and
geogenic emission sources.
Nitric Oxide (NO) is a colorless gas formed by combustion under high temperature and high
pressure in an internal combustion engine. It changes into nitrogen dioxide (NO2) in the ambient
air and contributes to photochemical smog. It is the most thermally stable of the oxides of
nitrogen.
Nitrogen Oxides (NOX) are a class of compounds that are respiratory irritants and that react with
volatile organic compounds (VOCs) to form Ozone (O3). The primary combustion product of
nitrogen is nitrogen dioxide (NO2). However, several other nitrogen compounds are usually
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emitted at the same time (nitric oxide [NO], nitrous oxide [N2O], etc.), and these may or may not
be distinguishable in available test data. They are usually in a rapid state of flux, with NO2 being,
in the short term, the ultimate product emitted or formed shortly downstream of the stack. The
convention followed in emission factor documents is to report the distinctions wherever possible,
but to report total NOX on the basis of the molecular weight of NO2. NOX compounds are also
precursors to acid rain. Motor vehicles, power plants, and other stationary combustion facilities
emit large quantities of NOX.
Nitrous Oxide (N2O) is a colorless gas with a mild, pleasing odor and sweet taste. Its behavior
resembles that of oxygen as an oxidizing agent with combustible substances. It is considered a
naturally occurring greenhouse gas.
Nonmethane Hydrocarbons (NMHCs) are a class of compounds that includes a wide range of
specific organic chemical substances, including reactive volatile organic compounds (VOCs),
which form Ozone, a greenhouse gas, in the troposphere. A major local and regional air
pollutant, they cause significant health and environmental damage.
Ozone (O3) is a colorless gas that damages lungs and can damage materials and vegetation. It is
the primary constituent of smog, and is formed primarily when nitrogen oxides (NOX) and volatile
organic compounds (VOCs) react in the presence of sunlight. It is also emitted in insignificant
quantities from motor vehicles, industrial boilers, and other minor sources.
Ozone Day is the time period (one day) that Ozone (O3) emissions are estimated for a daily Ozone
inventory. When modeling biogenic emissions, an Ozone day is selected from days with the
highest actual recorded Ozone, and the meteorology from that day is used in the model.
Photosynthetically Active Radiation (PAR) is the photon flux density in the visible (or
photosynthetic) portion of the spectrum (0.4 - 0.7 jim), expressed as the energy per square meter
per second.
Sky Cover is the amount of sky completely hidden by clouds or other obscuring phenomenon.
Sky cover is reported in tenths, so that 0.0 sky cover indicates a clear sky and 1.0 sky cover
indicates a completely covered sky.
Volatile Organic Compounds (VOCs) react with nitrogen oxides (NOX) in the atmosphere to
form Ozone (O3). Although not criteria pollutants, VOC emissions are regulated under criteria
pollutant programs because they are Ozone precursors. Large amounts of VOCs are emitted
from fuel distribution, chemical manufacturing, motor vehicles, and a wide variety of industrial,
commercial, and consumer solvent uses.
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The use of certain photochemical models requires estimation of methane, ethane, and several
other less photochemically reactive compounds and particulates. While not regulated as VOCs,
these compounds may need to be estimated for certain modeling inventories or to meet certain
state inventory requirements. For this reason, the term total organic compounds (TOCs) is used
to refer to this broader class of chemicals.
8.5 QUALITY ASSURANCE
100(1-a) Percent Confidence Interval of a Population Parameter means that if the process of
drawing n samples from the population is repeated many times and the 100(1-a) percent
confidence interval is computed each time, 100(1-a) percent of those intervals will include the
population parameter value.
Accuracy is (1) the closeness of a measurement to its true value, or (2) the degree of agreement
between an observed value and an accepted reference value. Accuracy includes a combination of
error (precision) and systematic error (bias) components that are due to sampling and analytical
operations; a data quality indicator.
Area Sources are smaller sources that do not qualify as point sources under the relevant emissions
cutoffs. Area sources encompass more widespread sources that may be abundant, but that,
individually, release small amounts of a given pollutant. These are sources for which emissions
are estimated as a group rather than individually. Examples typically include dry cleaners,
residential wood heating, auto body painting, and consumer solvent use. Area sources generally
are not required to submit individual emissions estimates.
Arithmetic Mean is the sum of all the values of a set of measurements divided by the number of
values in the set, usually denoted by x; also a measure of central tendency.
Attainment Area is an area considered to have air quality as good as or better than the National
Ambient Air Quality Standards (NAAQS) as defined in the Clean Air Act. Note that an area may
be in attainment for one or more pollutants but be a nonattainment area for one or more other
pollutants.
Audit of Data Quality means a qualitative and quantitative audit in which data and data handling
are reviewed and data quality is assessed.
Audits are systematic evaluations to determine the quality of a function or activity.
Average means the sum of all the items or observations in a sample divided by the number of
items in the sample. Synonymous with "sample mean."
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Bias is the systematic or persistent distortion of a measurement process or estimation method.
Biogenic Sources are biological sources of emissions such as trees, agricultural crops, or
microbial activity in soils or water. This term is sometimes used to describe any natural emission
source.
Chain of Custody is a trail of accountability that documents the physical security of samples,
data, and records.
Coefficient of Variation (CV) is the standard deviation expressed as a percentage of the mean.
Also see Relative Standard Deviation.
Comparability is the degree to which different methods, data sets, and/or decisions agree or can
be represented as similar; a data quality indicator.
Completeness is the amount of valid data obtained compared to the planned amount, usually
expressed as a percentage; a data quality indicator.
Confidence Interval is a range that has a designated probability (i.e., confidence level) of
including a specific population parameter.
Correction is an action taken to determine causes of quality defects and to restore proper
functioning of a system or procedure.
Criteria Pollutant refers to a pollutant for which a National Ambient Air Quality Standard
(NAAQS) has been set. Criteria pollutants are carbon monoxide (CO), lead (Pb), nitrogen oxides
(NOX), Ozone (measured as volatile organic compounds [VOCs]), paniculate matter of
aerodynamic diameter less than or equal to 10 micrometers (PM10), and sulfur dioxide (SO2).
Data are facts or figures from which conclusions can be inferred; information.
Data Attribute Rating System (DARS) is a system developed by the U.S. Environmental
Protection Agency (EPA) to evaluate emissions uncertainty by assigning numerical values to the
perceived quality of the emission factors and activity data.
Data Management Plan is a written document prepared prior to inventory development that may
be a part of the quality assurance (QA) plan. It describes the required inventory-development
records, the steps required to produce them, how the records are to be stored, the retention
period, the procedures for retrieving them, and the circumstances for their destruction.
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Data Quality Indicators are qualitative and quantitative descriptors used to interpret the degree
of acceptability or utility of data to the user. The principal data quality indicators are accuracy,
comparability, completeness, and representativeness.
Data Quality Objectives are qualitative and quantitative statements of the level of uncertainty that
a decision maker is willing to accept in the estimates and/or decisions made with emissions
inventory data.
Data Reduction is the process of transforming raw data by arithmetic or statistical calculations,
standard curves, concentration factors, etc., and collation into a more useful form.
Data Set refers to all observed values in a test or study; data collected under similar conditions
that can be analyzed as a whole.
Defensible means the ability to withstand reasonable challenge related to the veracity or integrity
of documents and derived data.
Emission means pollution discharged into the atmosphere from smokestacks, other vents, and
surface areas of commercial or industrial facilities; from residential chimneys; and from motor
vehicle, locomotive, aircraft or other nonroad engines.
Emission Factors are ratios that relate emissions of a pollutant to an activity level at a plant that
can be easily measured, such as an amount of material processed, or an amount of fuel used.
Given an emission factor and a known activity level, a simple multiplication yields an estimate of
the emissions. Emission factors are developed from separate facilities within an industry category,
so they represent typical values for an industry, but do not necessarily represent a specific source.
Published emission factors are available in numerous sources.
Emission Inventory is a listing, by source, of the amount of air pollutants discharged into the
atmosphere of a community; used to establish emission standards.
Emission Standards are a general type of standard that limit the mass of a pollutant
that may be emitted by a source. The most straightforward emissions standard is a simple
limitation on mass of pollutant per unit time (e.g., pounds of pollutant per hour).
Equivalent Method means any method of sampling and analyzing for air pollution that has been
demonstrated to the U.S. Environmental Protection Agency (EPA) Administrator's satisfaction to
be, under specific conditions, an acceptable alternative to normally used reference methods.
Fugitive Emissions are emissions not caught by a capture system.
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Hazardous Air Pollutants (HAPs) are listed in Section 112(b) of the 1990 Clean Air Act
Amendments (CAAA). These pollutants are emitted in smaller quantities than criteria pollutants
but may be reasonably anticipated to cause cancer, developmental effects, reproductive
dysfunctions, neurological disorders, inheritable gene mutations, or other chronically or acutely
toxic effects in humans. The CAAA specifies an initial list of 189 HAPs to be subject to further
regulation. The list of HAPs includes relatively common pollutants such as formaldehyde,
chlorine, methanol, and asbestos, as well as numerous less-common substances. Pollutants may,
under certain circumstances, be added to or deleted from the list.
Inventory Work Plan is a document that discusses staff assignments and responsibilities,
establishes a commitment to the inventory development and quality assurance/quality control
(QA/QC) processes, and establishes a commitment to personnel training and project
documentation requirements. It may either be integrated with the quality assurance plan (QAP)
or a separate document.
Level I, II, III, and IVInventories refer to categories delineated by the Emission Inventory
Improvement Program (EIIP) Quality Assurance (QA) Committee based on the intended use of
the inventory. Level I inventories are used to support enforcement, compliance, or litigation
activities. Level II inventories provide supportive data for strategic decision making or standard
setting. Level III inventories are developed for general assessments or research that will not be
used in direct support of decision making. Level IV inventories are compiled entirely from
previously published data or other inventories, and no original data are gathered.
Mean is synonymous with "average." Also called "arithmetic mean."
Measurement/Method Attribute is one of the four Data Attribute Rating System (DARS) data
attributes. It explicitly addresses the quality of the factor, not how it is applied.
Median is that value above which and below which half the sample population lies, in other
words, the value of the variable in an ordered array that has an equal number of observations on
each side of it.
Mobile Source means any nonstationary source of air pollution such as cars, trucks, motorcycles,
buses, airplanes, ships and boats, locomotives, and equipment with internal combustion engines.
Mode is the value represented by the greatest number of observations in a sample population.
Nonparametric Technique is one that does not depend upon data being drawn from a specific
distribution, such as the normal or log-normal, for its validity; a distribution-free technique.
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INTRODUCTION TO EIIP 6/27/97
Nonroad Emissions are pollutants emitted by internal combustion engines on farm and
construction equipment, gasoline-powered lawn and garden equipment, and power boats and
outboard motors. Also includes pollutants emitted by airplanes, ships, and locomotives.
Normal Distribution is a probability density function that approximates the distribution of many
random variables associated with measurements of natural phenomena and takes the form of a
symmetric "bell-shaped curve."
Observation refers to a fact or occurrence that is recognized and recorded.
Onroad Emissions are pollutants emitted by nonstationary sources of air pollution such as cars,
trucks, motorcycles, and buses.
Outlier is an observation that does not conform to the pattern established by other observations in
a data set.
Parameter is a variable, measurable property whose value is a determinant of the characteristics
of a system (e.g., temperature, pressure, and density are parameters of the atmosphere).
Performance Audit is a quantitative appraisal of quality that includes the use of an objective
standard or set of data to evaluate the effectiveness or accuracy of a system or procedure.
Point Sources are large, stationary, identifiable sources of emissions that release pollutants into
the atmosphere. Sources are often defined by state or local air regulatory agencies as point
sources when they annually emit more than a specified amount of a given pollutant, and how state
and local agencies define point sources can vary. Point sources are typically large manufacturing
or production plants. They typically include both confined "stack" emission points as well as
individual unconfmed "fugitive" emission sources.
Within a given point source, there may be several emission points that make up the point source.
Emissions point refers to a specific stack, vent, or other discrete point of pollution release. This
term should not be confused with point source, which is a regulatory distinction from area and
mobile sources. The characterization of point sources into multiple emissions points is useful for
allowing more detailed reporting of emissions information.
For point sources, the emission estimate reporting system used by most state and local air
regulatory agencies groups emission sources into one of three categories and maintains emission-
related data in a different format for each. The three categories are plant level, point level, and
process or segment level.
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6/27/97 INTRODUCTION TO EIIP
Population means all possible items or units that possess a variable of interest and from which
samples may be drawn.
Precision is (1) a measure of the closeness of agreement among individual measurements, and
(2) the closeness of repeated measurements of the same quantity.
Prevention is an orderly program of planning and positive actions taken before or during the
conduct of procedures to ensure that the procedures are effectively meeting the requirements for
which they are intended.
Probability Sampling is the use of a specific method of random selection of population units for
measurement.
Procedural Audit is an objective assessment of compliance to procedural requirements.
Quality is the sum of features and properties/characteristics of a product or service that bear on
its ability to satisfy stated needs.
Quality Assurance (QA) is a planned system of activities designed to provide assurance that the
quality control program is actually effective.
Quality Assurance Manual is a written document that identifies the policies, organization,
objectives, functional activities, and specific quality assurance activities designed to achieve the
quality goal desired.
Quality Assurance Objectives are project goals for accuracy, precision, completeness,
representativeness, and comparability of data gathered during testing.
Quality Assurance Plan (QAP) is a formal document describing the management policies,
objectives, principles, organizational authority, responsibilities, accountability, and implementation
plan of an agency or company for ensuring quality in its products and usefulness to its users.
Quality Control (QC) is a planned system of activities whose purpose is to provide quality
services or products.
Quality Trilogy refers to planning, control, and improvement.
Random Measurement Uncertainty refers to unpredictable deviation from the true value of a
parameter being measured.
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INTRODUCTION TO EIIP 6/27/97
Random Sampling Error is the variation in an estimated quantity due to the random selection of
parameters for measurement.
Reference Method is a sampling and/or measurement method that has been officially specified by
an organization as meeting its data quality requirements.
Relative Standard Deviation is the standard deviation expressed as a percentage of the mean
recovery (i.e., the coefficient of variation multiplied by 100).
Representativeness means that an inventory is representative of the region and sources it is meant
to cover; a data quality indicator.
Representative Sample refers to a sample that reflects the variable of interest in the population as
accurately and precisely as possible. To ensure representativeness, the sample may be either
completely random or stratified depending upon the conceptualized population and the sampling
objective.
Representative Unit means one selected from the target population that in combination with other
representative units will give an accurate picture of the phenomenon being studied.
Sample refers to a representative part of a large whole or a single item of a group; a finite part or
subset of a statistical population. A sample serves to provide data or information from which are
inferred the properties of the whole group or population.
Sample Mean. See Average.
Sample Variance (Statistical) means a measure of the dispersion of a set of values. The sum of
the squares of the difference between the individual values of a set and the arithmetic mean of the
set divided by one less than the number of values in the set. (This is equal to the square of the
sample standard deviation.)
Sampled Population is a set of population units available for measurement.
Sampling Error refers to that portion of the difference between a population value and an
estimate thereof that is due to only a limited number of all possible values being observed. This is
distinguished from errors due to imperfect selection, bias in response, or errors of observation,
measurement, or recording, etc.
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6/27/97 INTRODUCTION TO EIIP
Source Specificity Attribute is one of the four Data Attribute Rating System (DARS) data
attributes. It refers to how specific the original factor or activity surrogate is to the source being
estimated.
Spatial Congruity Attribute is one of the four Data Attribute Rating System (DARS) data
attributes. It addresses the spatial scaling of factors and activity data that is common to
inventories.
Standard Deviation (s.d.) is the most common measure of the dispersion or imprecision of
observed values expressed as the positive square root of the variance. See Sample Variance.
Standard Error is the standard deviation of a statistic, usually used to designate the standard
deviation of a sample mean.
Standard Method is an assemblage of techniques and procedures based on consensus or other
criteria, often evaluated for its reliability by collaborative testing and receiving organizational
approval.
Standard Operating Procedures (SOPs) refer to a written document that details the method of
an operation, analysis, or action whose techniques and procedures are thoroughly prescribed and
that is accepted as the method for performing certain routine or repetitive tasks.
State Implementation Plan (SIP) is a state plan approved by the U.S. Environmental Protection
Agency for the establishment, regulation, and enforcement of air pollution standards.
Stationary Source is a fixed-site producer of pollution, including power plants and other major
sources such as industrial manufacturing facilities as well as area sources.
Statistic is an estimate of a population characteristic calculated from a data set (observed or
corrected values) (e.g., the mean or standard deviation).
Statistical Bias refers to a discrepancy between the expected value of an estimator and the
population parameter being estimated.
Statistical Checks mean a miscellaneous set of tools/procedures that are part of quality assurance.
Also referred to as "statistical quality control."
Stratification means the division of a target population into subsets or strata that are more
internally homogeneous with respect to the characteristic to be studied than with the population
as a whole.
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INTRODUCTION TO EIIP 6/27/97
Stratified Sampling is the sampling of a population that has been stratified, with part of the
sample coming from each stratum. See Stratification.
Systems Audit is an on-site evaluation or assessment of the quality control program developed for
a project or laboratory. The audit is conducted by a trained auditor who is not directly involved
in the conduct of the work.
Systematic Error is a consistent deviation in the result from the expected or known value. Such
error is caused by human and methodological bias.
Target Population refers to the set of TV population units for which inferences will be made.
Technical Systems Audit is an on-site audit of a company's quality assurance system, physical
facilities, and implementation of approved procedures.
Temporal Congruity Attribute is one of the four Data Attribute Rating System (DARS) data
attributes. It describes the relationship between emission factor, activity, and temporal scale of
the inventory.
Total Quality Management is a system of activities designed to provide continuous improvement
at every level and in all areas of responsibility.
Trimmed Mean is the arithmetic mean of the data remaining after a specified percentage of the n
data in both tails of the distribution curve are discarded.
Uncertainty comprises two types of errors in estimation: bias and imprecision.
Uncertainty Analysis is conducted to identify and quantify the various sources of variability and
inaccuracies in data used to estimate emissions. It includes an assessment of bias and imprecision.
Validated Method is a method that has been determined to meet certain performance criteria for
sampling and/or measurement operations.
Variable is an entity subject to variation or change.
Variance is a fundamental statistical measure of dispersion, calculated by summing the standard
deviation of each sample from the mean and dividing that sum by the number of observations in
the sample.
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EIIP Volume I 1.8-25
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INTRODUCTION TO EIIP 6/27/97
APPENDIX A
EMISSION INVENTORY
IMPROVEMENT PROGRAM
COMMITTEE MEMBER LIST
EIIP Volume I
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EIIP Volume I
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6/27/97 INTRODUCTION TO EIIP
BMP COMMITTEE MEMBERS
STEERING COMMITTEE
Steve Bromberg
Emission Factor and Inventory Group (MD-14)
Environmental Protection Agency
Research Triangle Park, NC 27711
Phone: (919)541-1000
Fax: (919)541-0684
Cyril Durrenberger
Air Quality Planning Division
Texas Natural Resource Conservation Commission
12100 Park 35 Circle
Post Office Box 13087
Austin, TX 78753-3087
Phone: (512)239-1482
Fax: (512)239-1500
Linda Murchison
California Air Resources Board
Post Office Box 2815
Sacramento, CA 95812
Phone: (916)322-6021
Fax: (916)323-1075
Roger Westman
Allegheny County Health Department
301 39th Street
Pittsburgh, PA 15201
Phone: (412)578-8103
Fax: (412)578-8144
El IP Volume I A-l
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INTRODUCTION TO EIIP 6/27/97
STEERING COMMITTEE (Continued)
Donald Arkell
Lane Regional Air Pollution Authority
225 North 5th
Suite 501
Springfield, OR 97477
Phone: (541)726-2514
Fax: (541)726-1205
Darryl Tyler
Division of Air and Waste Management
State of Delaware
89 Kings Flighway
Post Office Box 1401
Dover, DE 19903
Phone: (302)739-4791
Fax: (302)739-3106
Herb Sherrow
Environmental Protection Agency, Region 6
First International Bank Tower at Fountain Place
Mail Code 6PD-L
1445 Ross Avenue
Dallas, TX 75202-2733
Phone: (214)665-7237
Fax: (214)665-7263
A-2 EIIP Volume I
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6/27/97 INTRODUCTION TO EIIP
POINT SOURCES COMMITTEE
Co-chairs
Dennis Beauregard
Emission Factor and Inventory Group (MD-14)
Environmental Protection Agency
Research Triangle Park, NC 27711
E-Mail: beauregard.dennis@epamail.epa.gov
Phone: (919)541-5512
Fax: (919)541-0684
Bill Gill
Emissions Inventory Section
Texas Natural Resource Conservation Commission
12100 Park 35 Circle
Post Office Box 13087
Austin, TX 78711-3087
(Federal Express ZIP Code 78753)
E-Mail: wgill@smtpgate.tnrcc.state.tx.us
Phone: (512)239-5750
Fax: (512)239-1515
Members
Denise Alston-Gulden
Gal son Consulting
6601 Kirkville Road
Syracuse, NY 13057
E-Mail: dralstong@aol.com
Phone: (800) 724-0669 or (315) 432-0506 (ext. 119)
Fax: (315)437-0509
Bob Betterton
South Carolina Department of Health and Environmental Control
Bureau of Air Quality
2600 Bull Street
Columbia, SC 29201
E-Mail: betterrj@columb31 .dhec.state.sc.us
Phone: (803)734-4549
Fax: (803)734-4556
EIIP Volume I A-3
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INTRODUCTION TO EIIP 6/27/97
POINT SOURCES COMMITTEE (Continued)
Paul Brochi
Emissions Inventory Section
Texas Natural Resource Conservation Commission
12100 Park 35 Circle
Post Office Box 13087
Austin, TX 78711-3087
(Federal Express Zip Code 78753)
E-Mail: pbrochi@smtpgate.tnrcc.state.tx.us
Phone: (512)239-1942
Fax: (512)239-1515
Alice Fredlund
Louisiana Department of Environmental Quality
Air Quality/Technical Services
Post Office Box 82135
Baton Rouge, LA 70884-2135
E-Mail: alice_f@deq.state.la.us
Phone: (504)763-3955
Fax: (504)765-0222
Gary Helm
Air Quality Management, Inc.
Post Office Box 8
Macungie, PA 18062
E-Mail: helm@enter.net
Phone: (610)967-1688
Fax: (610)967-0308
Paul Kim
Air Quality Division
Compliance Determination Unit
Minnesota Pollution Control Agency
520 Lafayette Road
St. Paul, MN 55155
E-Mail: paul.yw.kim@pca.state.mn.us
Phone: (612)296-7320
Fax: (612)297-7709
A-4 EIIP Volume I
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6/27/97 INTRODUCTION TO EIIP
POINT SOURCES COMMITTEE (Continued)
Toch Mangat
Bay Area Air Quality Management District
Planning Department
939 Ellis Street
San Francisco, CA 94109
E-Mail: tmangat@baaqmd.gov
Phone: (415)749-4651
Fax: (415)749-4741
Ralph Patterson
Wisconsin Department of Natural Resources
101 South Webster Street
7th Floor
Post Office Box 7921
Madison, WI 53707
E-Mail: patter@dnr.state.wi.us
Phone: (608)267-7546
Fax: (608)267-0560
Eitan Tsabari
City of Omaha
Air Quality Control Division
5600 South 10th Street
Omaha, NE 68107
E-Mail: etsabari@worldnet.att.net
Phone: (402)444-6015
Fax: (402)444-6016
EIIP Volume I A-5
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INTRODUCTION TO EIIP 6/27/97
POINT SOURCES COMMITTEE (Continued)
Jim Southerland
North Carolina Department of Environment,
Health and Natural Resources
Air Quality Division
Post Office Box 29580
Raleigh, NC 27626-0580
Federal Express Address:
2728 Capital Boulevard
Parker Lincoln Building
Raleigh, NC 27604
E-Mail: jim_southerland@aq.ehnr.state.nc.us
Phone: (919)715-7566
Fax: (919)715-7476
Robert Wooten
North Carolina Department of Environment,
Health and Natural Resources
Air Quality Section
Post Office Box 29580
Raleigh, NC 27626-0580
E-Mail: bob_wooten@aq.ehnr.state.nc.us
Federal Express Address:
2728 Capital Blvd.
Parker Lincoln Building
Raleigh, NC 27604
Phone: (919)733-1815
Fax: (919)715-7476
A-6 EIIP Volume I
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6/27/97 INTRODUCTION TO EIIP
AREA SOURCES COMMITTEE
Co-chairs
Carolyn Lozo
California Air Resources Board
Technical Support
Post Office Box 2815
2020 L Street
Sacramento, CA 95814-4219
Email: clozo@Ccleanair.arb.ca.gov
Phone: (916) 323-8372
Fax: (916) 323-1075
Charles Mann
Office of Research and Development
Air Pollution Prevention and Control Division (MD-61)
Environmental Protection Agency
Research Triangle Park, NC 27711
Email: mann.chuck@epamail.epa.gov or
cmann@engineer. aeerl. epa.gov
Phone: (919)541-4593
Fax: (919)541-7891
Members
Linda Murchison
California Air Resources Board
2020 L Street
Post Office Box 2815
Sacramento, CA 95812
Phone: (916)322-6021
Fax: (916)323-1075
Kwame Agyei
Puget Sound Air Pollution Control Agency
110 Union Street, Suite 500
Seattle, WA 98101-2038
Phone: (206)689-4054
Fax: (206)343-7522
EIIP Volume I A-7
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INTRODUCTION TO EIIP 6/27/97
AREA SOURCES COMMITTEE (Continued)
Mike Fishburn
Texas Natural Resource Conservation Commission
Emissions Inventory (MC-164)
Post Office Box 13087
Austin, TX 78711-3087
Email: mfishbur@smtpgate.tnrcc.state.tx.us
Phone: (512)239-1934
Fax: (512)239-1515
Gwen Judson
Wisconsin Department of Natural Resource
Air Management
101 South Webster Street
Post Office Box 7921
Madison, WI 53707-7921
Email: JUDSOG@dnr.state.wi.us
Phone: (608)266-1595
Fax: (608)267-0560
Sally Otterson
Washington Department of Ecology
Post Office Box 47600
Olympia, WA 98504-7600
Email: SOTT461@ecy.wa.gov
Phone: (360)407-6806
Fax: (360)407-6802
Lee Tooly
Emission Factor and Inventory Group, OAQPS (MD-14)
Environmental Protection Agency
Research Triangle Park, NC 27711
Email: tooly.lee@epamail.epa.gov
Phone: (919)541-5292
Fax: (919)541-0684
A-8 EIIP Volume I
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6/27/97 INTRODUCTION TO EIIP
AREA SOURCES COMMITTEE (Continued)
Jim Wilkinson
Maryland Department of the Environment
Air Management Administration
2500 Broening Highway
Baltimore, MD 21224
Phone: (410)631-3245
Fax: (410)631-3202
George Leney
Allegheny County Health Department
301 39th Street
Pittsburgh, PA 15201
Phone: (412)578-8131
Fax: (412)578-8144
Charles Masser
Office of Research and Development
Air Pollution Prevention and Control Division (MD-61)
Environmental Protection Agency
Research Triangle Park, NC 27711
Email: cmasser@engineer.aeerl.epa.gov
Phone: (919)541-7586
Fax: (919)541-7891
Richard Bode
California Air Resources Board
Technical Support
Post Office Box 2815
2020 L Street
Sacramento, CA 95814-4219
Email: rbode@cleanair.arb.ca.gov
Phone: (916) 322-3807
Fax: (916) 323-1075
EIIP Volume I A-9
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INTRODUCTION TO EIIP 6/27/97
MOBILE SOURCES COMMITTEE
Co-chairs
Rob Altenburg
Department of Environmental Protection
Bureau of Air Quality
Post Office Box 8468
Market Street State Office Building, 12th Floor
400 Market Street
Harrisburg, PA 17105-8468
Email: ALTENBURG.ROBERT@A1.DEP.STATE.PA.US
Phone: (717)787-4310
Fax: (717)772-2303
Greg Janssen
Office of Mobile Sources
Environmental Protection Agency
2565 Plymouth Road/AATSB
Ann Arbor, MI 48105
Email: JANSSEN.GREG@EPAMAIL.EPA.GOV
Phone: (313)668-4285
Fax: (313)668-4368
Members
Kwame Agyei
Puget Sound Air Pollution Control
110 Union Street
Suite 500
Seattle, WA 98101
Phone: (206)689-4054
Fax: (206)343-7522
Mark Janssen
Lake Michigan Air Directors Consortium (LADCO)
2350 East Devon Avenue
Suite 242
Des Plains, IL 60018
Email: LADCO@INTERACCESS.COM
Phone: (847)296-2181
Fax: (847)296-2958
A-10 EIIP Volume I
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6/27/97 INTRODUCTION TO EIIP
MOBILE SOURCES COMMITTEE (Continued)
Tom Kearney
New York Department of Transportation
Building 4, Room 104
1220 Washington Avenue
Albany, NY 12232
Phone: (518)457-7203
Fax: (518)457-8317
Wienke Tax
Environmental Protection Agency, Region 9
75 Hawthorne Street (A-2-1)
San Francisco, CA 94105
Email: TAX.WIENKE@EPAMAIL.EPA.GOV
Phone: (415)744-1232
Fax: (415)744-1076
Kim Fisher
FHWA
400 7th Street, Southwest
Washington, DC 20590
Phone: (202)366-5843
Fax: (202)366-4054
Lynne Hamlin
Texas Natural Resource Conservation Commission
Post Office Box 13087
Austin, TX 78711-3087
E-Mail: LHAMLIN@SMTPGATE.TNRCC.STATE.TX.US
Phone: (512)239-1951
Fax: (512)239-1500
David H. Lax
Senior Environmental Scientist
American Petroleum Institute
1220 L. Street, Northwest
Washington, DC 20005
Phone: (202)682-8479
Fax: (202)682-8270
El IP Volume I A-11
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INTRODUCTION TO EIIP 6/27/97
BIOGENIC SOURCES COMMITTEE
Co-chair
Tom Pierce
Modeling Systems Analysis Branch (MSAB)
Environmental Protection Agency
Research Triangle Park, NC 27711
Phone: (919)541-1375
Fax: (919)541-1379
Members
Janet Arey
State Wide Air Pollution Research Center
University of California-Riverside
Riverside, CA 92521
Marianne Causley
Systems Applications International
101 Lucas Valley Road
San Rafael, CA 94903
Alex Guenther
Atmospheric Chemistry Division
National Center for Atmospheric Research
Post Office Box 3000
Boulder, CO 80307
Gordon Hutchinson
U.S. Department of Agriculture - ARS
NPA Federal Building
301 South Howes
Room 435 POBE
Fort Collins, CO 80522
A-12 El IP Volume I
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6/27/97 INTRODUCTION TO EIIP
BIOGENIC SOURCES COMMITTEE (Continued)
Richard McNider
Earth System Science Laboratory
University of Alabama-Huntsville
Huntsville, AL 35899
Michael Rogers
Earth and Atmospheric Sciences
Georgia Tech
Atlanta, GA 30332
Thomas Sharkey
Department of Botany
132BirgeHall
430 Lincoln Drive
University of Wisconsin
Madison, WI 53706-1381
Ralph Valente
Atmospheric Science Department
Tennessee Valley Authority
Chemical Engineering Building 2A
Mussel Shoals, AL 35660
Eric Williams
National Oceanic and Atmospheric Administration
Aeronomy
R/E/AL7
325 Broadway
Boulder, CO 80303
Patricia Valesco
California Air Resources Board
Post Office Box 2815
Sacramento, CA 95812
Phone: (916)327-8170
Fax: (916)327-8524
El IP Volume I A-13
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INTRODUCTION TO EIIP 6/27/97
BIOGENIC SOURCES COMMITTEE (Continued)
Chris Geron
Air Pollution Prevention and Control Division (MD-61)
Environmental Protection Agency
Research Triangle Park, NC 27711
Phone: (919)541-4639
Fax: (919)541-5227
Cari Furiness
North Carolina State University
Box 8002
Raleigh, NC 27695-8002
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6/27/97 INTRODUCTION TO EIIP
QUALITY ASSURANCE COMMITTEE
Co-chairs
Tom Ballou
Virginia Department of Environmental Quality
629 East Main Street
Eighth Floor
Richmond, VA 23219
E-Mail: TRBALLOU@DEQ.STATE.VA.US
Phone: (804)698-4406
Fax: (804)698-4510
William B. Kuykendal
Emission Factor and Inventory Group, TSD, OAQPS (MD-14)
Environmental Protection Agency
Research Triangle Park, NC 27711
E-Mail: KUYKENDAL.BILL@EPAMAIL.EPA.GOV
Phone: (919)541-5372
Fax: (919)541-0684
Members
Lee Beck
Air Pollution Prevention and Control Division (MD-63)
Environmental Protection Agency
Research Triangle Park, NC 27711
E-Mail: LBECK@ENGINEER.AEERL.EPA.GOV
Phone: (919)541-0617
Fax: (919)541-7885
El IP Volume I A-15
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INTRODUCTION TO EIIP 6/27/97
QUALITY ASSURANCE COMMITTEE (Continued)
Victoria Chandler
North Carolina Department of Environment,
Health and Natural Resources
Air Quality Section
Post Office Box 29580
Raleigh, NC 27626-0580
Federal Express Address:
2728 Capital Blvd.
Parker Lincoln Building
Raleigh, NC 27604
E-Mail: VICKI_CHANDLER@AQ.EHNR.STATE.NC.US
Phone: (919)715-0972
Fax: (919)715-7476
Dale Shimp
California Air Resources Board
Technical Support Division
Post Office Box 2815
Sacramento, CA 95812
E-Mail: DSHIMP@ARB.CAGOV
Phone: (916)324-7156
Fax: (916) 323-1075, if no answer (916) 327-8524
Mena Shah
California Air Resources Board
Technical Support Division
Post Office Box 2815
Sacramento, CA 95812
E-Mail: MSHAW@CLEANAIR.ARB.CA.GOV
Phone:
Fax: 916-327-8524
Jim Tomich
Bay Area Air Quality Management District
939 Ellis Street
San Francisco, C A 94109
E-Mail: JT@MERKLE.BAAQMD.GOV
Phone: (415)749-4682
Fax: (415)749-4949
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6/27/97 INTRODUCTION TO EIIP
QUALITY ASSURANCE COMMITTEE (Continued)
Sheila Holman
North Carolina Department of Environment,
Health and Natural Resources
Air Quality Section
Post Office Box 29580
Raleigh, NC 27626-0580
Federal Express Address:
2728 Capital Blvd.
Parker Lincoln Building
Raleigh, NC 27604
E-Mail: SHEILA_HOLMAN@AQ.EHNR.STATE.NC.US
Phone: (919)715-0971
Fax: (919)733-1812
Denise Bien
Ohio Department of Environmental Services
1632 Central Parkway
Cincinnati, OH 45210
E-Mail: DBIEN@DOES.LAA.CO.HAMILTON.OH.US
Phone: (513)333-4706
Fax: (513)651-9528
El IP Volume I A-17
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INTRODUCTION TO EIIP 6/27/97
DATA MANAGEMENT COMMITTEE
Co-chairs
John Slade
Pennsylvania Department of Environmental Resources
Bureau of Air Quality
Post Office Box 8468
400 Market Street, 12th Floor
Harrisburg, PA 17105-8468
E-Mail: SLADE.JOHN@A1.DEP.STATE.PA.US
Phone: (717)783-9476
Fax: (717)772-2303
Lee Tooly
Emission Factor and Inventory Group, (MD-14)
Environmental Protection Agency
Research Triangle Park, NC 27711
E-Mail: TOOLY.LEE@EPAMAIL.EPA.GOV
Phone: (919)541-5292
Fax: (919)541-0684
Members
Cheryl Taylor
California Air Resources Board
Post Office Box 2815
Sacramento, CA 95812
Phone: (916)324-7168
Fax: (916)323-1075
A-18 El IP Volume I
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6/27/97 INTRODUCTION TO EIIP
DATA MANAGEMENT COMMITTEE (Continued)
Geoff Mai one
Merck
1 Merck Drive
Post Office Box 100
Mail Drop WS1E-12
Whitehouse Station, NJ 08889-0100
E-Mail: GEOFFREY_MALONE@MERCK.COM
Phone: (908)423-5061
Fax: (908)735-1151
Trace Terrin
Maricopa County Air Pollution Control
2406 South 24th Street
Suite E 214
Phoenix, AZ 85034
E-Mail: TTERRIN@ESENVMGMT.MARICOPA.GOV
Phone: (602)506-6883
Fax: (602)506-6179
Carrie Eastman
Pennsylvania Department of Environmental Resources
Bureau of Air Quality
Post Office Box 8468
400 Market Street, 12th Floor
Harrisburg, PA 17105-8468
E-Mail: EASTMAN.CARRIE@A1 .DEP.STATE.PA.US
Phone:
Fax:
Chuck Isbell
ITPID/Information Management Group
OAQPS (MD-12)
Environmental Protection Agency
Research Triangle Park, NC 27711
Phone: (919)541-5448
Fax: (919)541-0684
El IP Volume I A-19
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INTRODUCTION TO EIIP 6/27/97
DATA MANAGEMENT COMMITTEE (Continued)
Mike Fishburn
Texas Natural Resource Conservation Commission
Emissions Inventory (MC-164)
Post Office Box 13087
Austin, TX 78711-3087
Email: MFISHBUR@SMTPGATE.TNRCC.STATE.TX.US
Phone: (512)239-1934
Fax: (512)239-1515
Leo Foretich
Louisiana Department of Environmental Quality
7290 Bluebonnet
Baton Rouge, LA 70884-2135
Phone: (504)765-0899
Fax: (504)765-0222
A-20 EIIP Volume I
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6/27/97 INTRODUCTION TO EIIP
GOVERNMENTAL INTERACTIONS COMMITTEE
Co-chair
Dave Mobley
Emission Factor and Inventory Group (MD-14)
Environmental Protection Agency
Research Triangle Park, NC 27711
Phone: (919)541-4676
Fax: (919)541-0684
Members
Dale Krygielski
City of Toledo
Division of Air Pollution Control
26 Main Street
Toledo, OH 43605
Phone: (419)697-5105
Fax: (419)693-2512
Greg Janssen
Office of Mobile Sources
Environmental Protection Agency
2565 Plymouth Road/AATSB
Ann Arbor, MI 48105
Phone: (313)668-4285
Fax: (313)668-4368
Sterlin Woodard
Chief, Air Compliance
Air Program
Environmental Protection Commission
1410 North 21st Street
Tampa, FL 33605
Phone: (813)272-5530
Fax: (813)272-7144
EIIP Volume I A-21
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INTRODUCTION TO EIIP 6/27/97
Herb Sherrow
Environmental Protection Agency, Region VI
Mail Code 6T-AP
1445 Ross Avenue, Suite 1300
Dallas, TX 75202-2733
Phone: (214)665-7237
Fax: (214)665-2164
A-22 EIIP Volume I
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