**TECHNICAL GUIDANCE FOR TRIBES ON**

**AIR MONITORING ISSUES**

*(Draft \-- format of NAAMS document)*

February 2006

**U. S. Environmental Protection Agency**

**Research Triangle Park, NC**

**Table of Contents**

**Technical Guidance for Tribes on Air Monitoring Issues**

**Section 1. Purpose and Audience** (Rewrite of old Section I)

**Section 2. History of Tribal Monitoring and Tribal Perspective** (New
with addition of Section XII)

**Section 3. Background Technical Information** (\~about 50% of old
Section III)

**Section 4. Tribal Air Quality Issues, Relevant Ambient Air Monitoring,
andCurrent and Recent Tribal Air Monitoring Activities Directed Towards
These Issues** (old Section IV)

**Section 5. Implementation of Monitoring** (old Section V identifing
all things that need to be done, e.g., Q/A, siting requirements, report
to AQS, etc.)

**Section 6. How to Request EPA Funding and Other Support** (old Section
X)

**Section 7. Storage and Access to Monitoring Data** (old Section VIII)

**Section 8. Understanding Monitoring Data and Its Implications** (old
Section VII)

**Section 9. Assessment of Ambient Air Quality in Indian Country in the
Absence of Air Monitoring** (old Section IX)

**Section 10. Other Air Quality Management Program Elements** (old
Section XI)

**1. Purpose and Audience** (This entire section probably needs to be
rewritten specific to technical guidance for tribes.)

**1.1 Background on EPA's Tribal Air Monitoring Program**

EPA's tribal air policy emphasizes that as sovereign governments, tribes
set their own air program goals. Therefore, EPA's goal for the tribal
air program is appropriately to help the tribes understand their air
quality problems and to establish and meet their air quality goals,
rather than to set goals or timetables for the tribes.

Tribes are diverse in their air quality problems, challenges, and
capabilities. In addition, tribes often also face non-air risks to the
health of their members \-- as well as other challenges and
disadvantages \-- that are different from those facing non-tribal
communities. Because of the diversity in situations and goals from tribe
to tribe, EPA has taken the approach of delegating to the Regional
Office level the tasks of assisting tribes in identifying their goals
and the task of managing the available resources to help meet those
goals. Because Regions understand individual tribal situations,
effective decisions about funding and in-kind assistance are best made
at the Regional Office level. Regional Offices have taken the initiative
on helping tribes set air quality goals and design ambient monitoring to
support them. Regions have prioritized requests from tribes when they
collectively exceed the tribal air management grant funds available to
the Regional Office. Regional Offices also negotiate, award, and manage
grants to individual tribes. Regional Offices provide in-person,
telephone, and written guidance and assistance to the tribal governments
at all these stages. Technical training on the actual operation of
monitors is available to tribes through the Tribal Air Monitoring
Support (TAMS) Center, which is supported by a grant from EPA
Headquarters. To date, Regional Offices and individual tribes have
entered into grants that have dedicated a portion of the available
tribal air management resources to plan, establish, and operate
approximately \[insert #\] ambient air monitoring stations in Indian
country.

In the course of this deliberately highly decentralized process,
Headquarters and Regional Offices have prepared a limited body of
strategic guidance on tribal air monitoring, i.e., guidance on deciding
whether to monitor, what type of monitoring to do, and how EPA will
prioritize requests for funding assistance. This guidance is rather
general in nature, reflecting the need to accommodate the diversity of
tribal situations.[^1] In addition to this limited body of strategic
guidance, tribes have access to the large body of EPA guidance on
monitoring technologies, quality assurance, and data management. While
originally prepared for use by state and local government agencies, this
technical guidance is equally applicable to monitors in tribal settings.

**1.2 Purpose of this Guidance Document**

This guidance document is not intended to modify any existing EPA
policies on tribal air quality management. The intended purpose of this
guidance document is to improve the ability of tribes and regional
offices to prioritize monitoring resources and to accomplish the
following:

\(1\) ensure that tribal goals for tribal air monitoring projects are
clearly stated and documented in grant agreements (or other suitable
forms) before resources under EPA management are applied, that progress
in meeting those goals is tracked, and that tracking results are used to
make adjustments when appropriate.

*Do we want to imply that regions are not applying standards
consistently?*

\(2\) serve as a useful information resource for tribes as they
determine their need for monitoring, work plans and grant applications,
as well as a one stop resource for locating technical information.

\(3\) assist tribes to understand monitoring data.

*How do we do this?*

\(4\) help integrate and coordinate tribal and state/local/national
monitoring strategies and activities.

*How? What does this mean? Section 4?*

\(5\) Recognize the need for flexibility to address the unique needs of
individual tribes.

*Is this a separate point? Put in intro?*

**1.3 Audience**

The intended audiences for this document are tribal environmental
professionals and EPA Regional Office and Headquarters staff who are
involved in resource allocations, tribal air grant award and management,
program evaluation, strategic planning of monitoring networks, or
technical support to monitoring programs. State monitoring officials may
also benefit from reading this document, as it may improve their
understanding of tribal goals and how EPA strives to help tribes meet
their goals. This should allow them to collaborate more efficiently with
tribes whenever collaboration serves state and tribal objectives.

*This section is OK. If we adopt Bill's proposed new organization then
we need to make sure the new organization addresses different
audiences.*

**1.4 Relationship to EPA's Strategic Plan, Budget, and Program
Assessment Process**

EPA's Strategic Plan for 2003-2008 contains this statement regarding
EPA's commitment to work with tribes:

EPA is committed to working with tribes on a government-to-government
basis to develop the infrastructure and skills tribes need to assess,
understand, and control air quality on their lands. We will increase air
monitoring in Indian country, and, in consultation with tribes, we will
establish needed federal regulatory authorities and help tribes develop
and manage their own air programs in a manner consistent with EPA Indian
Policy and tribal traditions and culture. We plan to complete a policy
determining when Federal Implementation Plans are appropriate for
bringing Clean Air Act programs to Indian country. We will support
tribal air programs by providing technical support, assistance with data
development, and training and outreach, and we will help tribes
participate in discussions of national policy and operations and in
regional planning and coordination activities. Where tribes choose not
to develop their own programs, we will implement air quality programs
directly.

In developing its annual budget plans, EPA considers whether sufficient
resources are available to support tribal air monitoring that is
necessary and appropriate to protect air quality in Indian country or to
provide important data that helps meets state, local, or national
monitoring data needs. Each year, EPA's budget request to Congress
requests a certain amount of funding for use in giving to grants to
tribes to support air quality management. For the last several years,
Congress has appropriated about \$11 million for this purpose.[^2] It
has become apparent that increasing numbers of tribes are interested in
establishing monitoring stations, and that not all interested tribes
will be able to obtain EPA financial support for ambient air monitoring
if resources for tribal air quality management remain steady. Many if
not all Regional Offices report that already they are not able to meet
all requests to provide grant funds for tribal air monitoring. Other
than reporting this situation, this guidance document is not intended to
examine or make recommendations regarding the overall level of EPA
funding and in-kind support to tribal air quality management. EPA
considers this and other budget issues through other processes. The
experience of working across Headquarters and Regional Office and with
tribal professionals in the course of preparing this guidance document
\[will/has\] better informed EPA staff about the tension between
resources and needs, and will inform EPA budget decision-makers in
future years.

The Office of Management and Budget (OMB) on a regular basis assesses
EPA's Air Program to determine how well each part of the Air Program is
managed in terms of having appropriate, and well defined goals; applying
resources towards those goals; providing guidance to partners who help
meet the goals; having systems in place to observe how well the goals
are met; and making adjustments in the program when necessary to reach
those goals. In addition to meeting OMB expectations, this "goals and
feedback" model is just good common sense because it helps make sure
that limited resources are used in ways that best meet the right goals.
Programs that are found by OMB to have serious weaknesses in management
are asked to make corrections and face the possibility of funding
reduction in future year budget proposals to Congress.

The most recent round of review of the NAAQS air quality program by OMB
has made EPA managers and staff more conscious about the importance of
being able to document that the tribal assistance portion of the Air
Program meets OMB measures and goals, guides participants to meet those
goals, tracks progress, and make adjustments when needed. This guidance
document on tribal air monitoring is a new part of such documentation.

It should be noted that unlike most EPA programs, the goals of the
tribal air monitoring program have been set by the Regional offices and
tribes with general guidance from Headquarters and OAQPS. A result is
that people inside and outside of EPA who are not personally involved in
working with tribes on monitoring projects need the benefit of reporting
systems to be able to be aware of and assess what is being accomplished
with available resources. The preparation of this document represents
one cycle of such assessment and reporting, in that current and recent
tribal air monitoring programs are reviewed in Section IV.

**~~1.5 The Tribal Perspective~~** (this section can probably be
dropped--JAT)

~~EPA received comment from NTAA and tribal professionals in October on
the 11/05 draft. As a result of the comments received, we divided the
Guidance effort into two documents: (1) EPA Guidance to identify and
prioritize resources related to tribal air quality, and (2) Monitoring
Guidance for tribes. The Tribal perspective section will appear in both
documents.~~

~~Both documents convey EPA guidance and reflect EPA policies and both
will be developed by a workgroup that include tribal environmental
professionals. EPA has opened the development of this document to all
interested tribal environmental professionals to assist us to make a
document that takes into account tribal input and is meaningful to
tribes, as well as to EPA. To ensure that tribal views are represented,
particularly if they are not the same views as those represented in this
document, we are at various points in the document delineating text
blocks which will offer comment or reaction from the tribal perspective.
These passages are provided by tribal environmental professionals and
NTAA and do not represent EPA policy or guidance, but may be useful to
some or all readers of this document.~~

**2. History of Tribal Monitoring and Tribal Perspective**

1.  **History of Tribal Monitoring**

(to be completed)

2.  **Tribal Perspective**

In 2004, the Environmental Protection Agency produced a final draft
document on their National Ambient Air Monitoring Strategy (NAAMS).
(This document should be reviewed and commented upon by this group). The
EPA says interesting and positive things about the integration of tribes
in the national air monitoring strategy document.  EPA had decided
originally to do a separate air monitoring strategy for tribes so that
tribes would not get "lost" in the national strategy. This is an
important issue.

One of the motivations for tribes to want to monitor the air quality are
human health issues; it is not a scientific interest in this subject.
This motivation is not addressed in the NAAMS. But the NAAMS document
must be examined for it has many useful details that address tribal air
monitoring.

It is useful to refer to this document: the National Ambient Air
Monitoring Strategy.  Some important points in it are:

EPA's entire air monitoring structure has clearly moved to the Ncore
strategy. This document states that there is a role for tribal
participation in several Levels of this strategy. These Levels are
clearly framed in this NAAMS document. And the role of tribes is clearly
stated.

Ambient monitoring systems are a critical part of America's air program
infrastructure. Air data from these monitoring systems are used to do
several things, such as: characterize "air quality" and associated
health and ecosystem impacts, to develop emission strategies to reduce
adverse impacts, and to account for air quality progress over time.

The United States spends well over \$200 million annually on routine

ambient air monitoring programs, a figure dwarfed by the billions
associated with emission reduction strategies. The ambient air data
provide a basis for an accounting of an air programs progress. Therefore
you can determine the value of those investments.

The Ncore strategy , mentioned in the NAAMS, talks about:

> Comprehensive monitors, (55 in rural areas) and Level 3 monitors
> (1,000 monitors specifically for local concerns, hotspots, etc).  The
> 2004 EPA Draft Monitoring Strategy also states that tribes have the
> right to participate in this Ncore strategy. Clearly the tribes have a
> purpose and a right to be involved with this strategy.

In this NAAMS there is fairly clear statement of tribal needs:

> "The prevailing air monitoring issues for Tribes include a severe
> shortage of resources for equipment, maintenance, operations,
> personnel and training".

This Tribal Perspective supports the NAAMS statement of need. The tribes
care about monitoring for human health reasons, not necessarily
scientific reasons. And the tribes need resources for air monitoring on
tribal lands.

The NAAMS highlights the fact that the Ncore strategy could benefit from
including tribes because the tribes can provide additional monitoring
sites, fill data gaps, and identify background conditions. These are the
reasons how tribal air monitoring could help the entire strategy. Tribal
monitoring can help this air quality infrastructure.

Many tribes are in isolated areas, but are subject to poor downwind air
quality. The tribes want to know the air quality data, and the effects
on human health. This is the reason that many tribes want their own air
monitors. Human health issues are of the utmost importance to tribes
(you cannot take care of "Mother Earth" without your own health being
good).

The NAAMS document also acknowledges that the priority for tribes is not
just trying to be useful for the national strategy, but that:

> "Monitoring priorities must be based on [Tribal
> decisions]{.underline}, which in many cases involve developing a
> better characterization of local exposure to air pollutants."

The NAAMS mentions the benefits of the TAMS center in Las Vegas, NV.
This center for tribal air work is an important tool for the tribes. It
helps the tribes in many ways to deal with their ambient air monitoring.

The NAAMS mentions the RPO's in integrating tribes into larger air
monitoring strategies. The RPO's help tribes and states work on air
issues, it brings them together for work on air monitoring. There must
be team work on all levels to preserve air quality.

The NAAMS document recognizes that tribes will benefit by being able to
identify threats to health. Tribes must be able to deal with air
monitoring on tribal lands. Tribes do not trust the states or the
Federal government to do this for them because of past historical
experience. But the basic fact is that the Federal government and the
Environmental Protection Agency have written into its basis, the
protection of the tribes.

The original Tribal Monitoring Strategy paper spoke of the Ncore
strategy. As outlined in the Ncore strategy, finding a meaningful way to
participate in that strategy is important. A tribal affiliated group,
such as the Institute for Tribal Environmental Professionals (ITEP),
should be identified to do the "representativeness" analysis for all
tribes, in certain regions of the US. Identifying those tribes that is
not currently represented by the Ncore network should be made. These
tribes should have access to the regional air monitoring data to see the
status of their air quality.  This project should also be aimed at
locating tribes that would serve to fill data gaps, and those that have
air pristine enough to provide background conditions. A perfect example
of how this could be performed is when ITEP worked with the Western
Regional Air Partnership (WRAP).

Below is a template for this process. It discusses how ITEP worked with
tribes in the West to uncover these tribal issues. Perhaps this template
could be used over the entire US:

> In 1996, the Grand Canyon Visibility Transport Commission (GCVTC, the
> predecessor to WRAP) identified a need for emissions inventories and
> air monitoring on and near tribal lands in the Western USA. We need to
> do this Nation wide for all tribes. This western US project, funded by
> the Western Regional Air Partnership's (WRAP) Tribal Data Development
> Working Group (TDDWG), served as a first step in gathering existing
> information on tribal air quality in the WRAP region. This is an
> important template for all of the US. The purpose of this project was
> to assess the current state of tribal air quality data and programs in
> the WRAP region and to clarify future needs in tribal air quality data
> development. The information collected and summarized is meant to
> inform the committees on the magnitude of the gap in air quality data
> over tribal lands, in the West. It is also meant to provide a starting
> point for planning future data development efforts in Indian Country,
> all over the USA.

Several critical issues were identified through this project, they
include:

-   A serious limitation on environmental program resources among the
    WRAP tribes.

-   A high demand for new and continuing tribal air quality programs in
    the WRAP region.

-   A shortage of tribal staff to deal with air quality issues.

The following will describe how these issues were identified and could
be a template for how this could be accomplished all over the USA.

ITEP was contracted to gather information on tribal air programs in the
WRAP region for this project. ITEP compiled a list of the 237 federally
recognized tribes in the WRAP region, along with environmental and/or
air program contacts for each of the tribes. ITEP attempted to contact
220 of these tribes and 156 tribes completed the assessment instrument.
ITEP staff persons were assigned to make all of the contacts.

One of the critical findings of ITEP's inquiries was a serious
limitation on environmental program resources among the WRAP tribes.
This is true all over the US. Information gathered in 2001, for the
western states indicated that only 22% of the 156 tribes it contacted
are currently involved in the WRAP. Of those not currently involved in
the WRAP, 41% indicated that they were not involved due to lack of staff
and/or resources. Twenty-five percent (25%) said that they were not
aware of the WRAP prior to the ITEP phone call. This data suggests a
need for a more active outreach program for tribes. This is true all
over the US.

The shortage of tribal staff to deal with air quality issues was
apparent in every phase of the WRAP project. It was difficult to
schedule meetings due to tribal staff's full schedules. Additional staff
in tribal air programs would increase the quality and quantity of tribal
air programs, as well as provide tribal staff with time for informed and
meaningful participation in air monitoring work.

Research also revealed a high demand for new and continuing tribal air
quality programs in the WRAP region, and across the USA. When asked if
the tribe had an air program, 38% (60 tribes) said that they did. The
other 96 tribes indicated that they did not have an air program.
Planning to meet the demands for tribal air programs should be underway,
not only for these new tribes but for the tribes that have been found to
be seriously understaffed**.** As more tribes endeavor to assess,
monitor and protect their air quality, additional resources must be
identified to support quality tribal air programs.

Many tribes in the WRAP region effect air quality through prescribed
burning programs. One hundred fifty-six (156) tribes were asked if
prescribed burning occurred on their reservation. Approximately half
(76) of the tribes responding said that prescribed burning did occur on
their reservation. An additional 14 tribes, who do not currently use
prescribed burns, indicated that they plan to use them in the future.
This information indicates that tribes should play an integral part in
regional planning of fire emissions. Air monitoring is important where
use of fire occurs often. This happens on tribal lands, and monitoring
of the air is an important issue for tribes concerned with human health.

This project identified several challenges and opportunities for tribal
air quality programs

in the Western USA, and could be used as a template all over the USA.

\[The coordinator/authors for this section may choose to convey the
tribal perspective by the use of delineated text blocks within other
individual sections as well as including this section.\]

**3. Background for Planning Tribal Air Monitoring**

**3.1 Introduction**

This section contains general background on ambient air monitoring, as
well as other technical information that is not specifically about
tribal monitoring. It is intended to assist tribal professionals who are
not already familiar with this material, so that they can participate
more easily and effectively with EPA staff. In order to be brief and
understandable to tribal professionals unfamiliar with the history,
complexity, and technology of air monitoring and related topics, this
section consists of thumbnail sketches and pointers to other documents
for fuller descriptions. The thumbnail sketches are simplified and do
not convey all provisions or nuances. They are intended to assist tribal
staff in understanding the more detailed references, and in discussing
these topics with EPA specialists and more experienced tribal
professionals. Additional substantial amounts of information concerning
(1) technical issues related to monitoring, emissions inventories and
air data, (2) health and ecosystem-related topics, as well as (3) the
Clean Air Act and associated EPA rules, and (4) government policies,
program planning, budgets and grants, can be found by tribal
professionals working through the following Internet addresses:

-   Clean Air Act \-- <http://www.epa.gov/air/caa/>

-   Chief Financial Officer (EPA) \--
    <http://www.epa.gov/ocfo/index.htm>

-   American Indian Environmental Office (EPA) \--
    <http://www.epa.gov/indian/index.htm>

-   Tribal Air (EPA/OAR) \-- <http://www.epa.gov/air/tribal/>

-   Technology Transfer Network (EPA/OAR) \-- <http://www.epa.gov/ttn/>

-   Institute for Tribal Environmental Professionals \--
    <http://www4.nau.edu/itep/programs/>

**3.2 Ambient Monitoring Technology Information Center (AMTIC)**

The AMTIC Internet website contains information and files on ambient air
quality monitoring programs, details on monitoring methods, relevant
documents and articles, information on air quality trends and
nonattainment areas, federal regulations related to ambient air quality
monitoring, as well as information on training, contacts and related
Internet sites. The AMTIC Internet website is a valuable starting point
for tribal members seeking information on a wide range of air monitoring
topics; its Internet address is:

\-- <http://www.epa.gov/ttn/amtic/>

**3.3 National Ambient Air Monitoring Strategy**

The overarching goal of the draft National Ambient Air Monitoring
Strategy is to improve the scientific and technical competency of the
nation's air monitoring networks while increasing the ability to protect
public and environmental welfare, and to accomplish this in flexible
ways that accommodate future needs in an optimized resource constrained
environment. Objectives in achieving this broad based goal include:
manage the Nation's air monitoring networks, establish a new air
monitoring approach, provide a greater degree of timely public air
quality information, improve network efficiencies, foster the
utilization of new measurement method technologies, encourage
multi-pollutant measurements, provide a base air monitoring structure,
develop and implement a major public information and outreach program,
seek input from the scientific community, provide air monitoring
platforms and data bases, and assess funding levels needed to maintain
support for this monitoring strategy. The impact of this strategy on
tribal monitoring is also addressed, including operation of monitoring
sites by Tribes. Tribal monitoring programs should consider their
activities in relation to implementation of this strategy and should be
poised to influence the strategy as it evolves. The draft monitoring
strategy document (December 2005) and supporting documents, which
provide both a description of the strategy and reflect ongoing
components of the strategic plan development, are available at the
following Internet addresses:

\-- <http://www.epa.gov/ttn/amtic/monstratdoc.html>

\-- <http://www.epa.gov/ttn/amtic/monitor.html>

**3.4 Existing State/Local/Tribal Monitoring Networks**

Ambient air monitoring programs make it possible to evaluate the status
of the

atmosphere compared to clean air standards and historical information. A
review of

various air monitoring networks (e.g., SLAMS, NAMS, PAMS, SPMS,
including

tribal monitoring) is provided as part of the National Ambient Air
Monitoring Strategy.

That strategy and other relevant information (including types, purposes,
history, funding)

of monitoring networks, including tribal programs, are provided at the
following addresses:

> \-- <http://www.epa.gov/oar/oaqps/qa/monprog.html#Ambient>

\-- <http://www.epa.gov/oar/oaqps/montring.html>

> \--
> <http://www.epa.gov/ttn/amtic/files/ambient/monitorstrat/naamstrat2005.pdf>

\-- <http://www.epa.gov/ttn/amtic/amlinks.html>

\-- <http://www.epa.gov/castnet/>

> \-- <http://vista.cira.colostate.edu/improve/Default.htm>

\-- <http://nadp.sws.uiuc.edu/>

\-- <http://www4.nau.edu/tams/services/index.html>

\-- <http://www.epa.gov/air/tribal/tribetotribe.html>

**3.5 Quality Assurance (QA) of Air Monitoring Programs**

EPA uses its Quality System to manage the quality of environmental data
collection, generation, and use; the primary goal is to ensure that data
are of sufficient quantity and quality to support decisions for
protecting the public and the environment. The Ambient Air Monitoring
Quality Assurance program applies these principles to air quality data.
This is accomplished through effective communication and cooperation
with monitoring organizations, which include EPA, State, Local, Tribal
agencies, the academic community and industry. To address QA
requirements and associated resource needs, the following tools are
routinely provided: gu[idance
documents](http://www.epa.gov/airprogm/oar/oaqps/qa/index.html#guidance%23guidance),
[The National Performance Evaluation
Program](http://www.epa.gov/airprogm/oar/oaqps/qa/index.html#NPEP%23NPEP),
data quality assessments and reports, [ambient air quality assurance
training](http://www.epa.gov/airprogm/oar/oaqps/qa/index.html#training%23training),
and example QA project plans (QAPPs). Information on QA tools, QA
requirements, and example applications should be given major
consideration in the development of tribal monitoring programs; this
information is available at the following Internet addresses:

\-- <http://www.epa.gov/quality/index.html>

\-- <http://www.epa.gov/airprogm/oar/oaqps/qa/index.html>

\-- <http://www.epa.gov/ttn/amtic/quality.html>

\-- <http://www.epa.gov/ttnamti1/files/ambient/airtox/nattsqapp.pdf>

**3.6 Air Quality System (AQS)**

The AQS is EPA's widely used repository of ambient air quality data. AQS
stores data from over 10,000 monitors, 5000 of which are currently
active. State, Local and Tribal agencies collect the data and submit it
to AQS on a periodic basis. Tribes conducting air monitoring programs
should strongly consider submitting the resulting air data to AQS, if
they are not already doing so. A detailed description of AQS, supporting
manuals and guides, web-based access, information on training, and links
to other sources of air quality information, including
State/Local/Tribal agencies, is provided at the following Internet
address:

\-- <http://www.epa.gov/ttn/airs/airsaqs/>

**3.7 ITEP and TAMS Support**

The Internet home page for the Institute for Tribal Environmental
Professionals (ITEP) states that "ITEP was established in 1992 to assist
Indian Tribes in the management of their environmental resources through
effective training and educational programs." The subcomponent for the
Tribal Air Monitoring Support Center states that \"The Tribal Air
Monitoring (TAMS) Center was created through a partnership between
Tribes, the Institute for Tribal Environmental Professionals and the
United States Environmental Protection Agency. It is the first technical
training center designed specifically to meet the needs of tribes
involved in air quality management and offers an array of training and
support services to Tribal air professionals. The TAMS Center mission is
to strive to develop tribal capacity to assess, understand and prevent
environmental impacts that adversely affect health, cultural, and
natural resources.\" Listings of training programs and services
available to tribal programs are provided at the following Internet
addresses:

\-- <http://www4.nau.edu/itep/>

\-- <http://www4.nau.edu/tams/>

**3.8 National Emissions Inventory (NEI)**

The National Emissions Inventory is a national data base of air
emissions information with input from numerous State and local air
agencies, from tribes, and from industry. This data base contains
information on stationary and mobile sources that emit criteria air
pollutants and their precursors, as well as hazardous air pollutants
(HAPS). The data base includes estimates of annual emissions, by source,
of air pollutants in each area of the country, on an annual basis.
Emissions estimates for individual point or major sources (facilities),
as well as county level estimates for area, mobile and other sources,
are available currently for 1990 and 1996 through 1999 for criteria
pollutants, and for 1999 for HAPs; a final version of the 2002 NEI will
be ready in early 2006. The NEI emissions data base is a key source of
information useful to tribal air programs. More information about the
NEI data base and the compilation of criteria pollutant and HAP
emissions inventories, and links to the data base, are available at the
following Internet addresses:

> \-- <http://www.epa.gov/ttn/chief/net/index.html>
>
> \-- <http://www.epa.gov/ttn/chief/eiinformation.html>

**3.9 Air Quality Models**

Air quality models, and how they can provide insight to ambient air
quality in Indian country when monitoring is not available, should be of
particular interest to tribes. There are three types of air quality
models: dispersion, photochemical, and receptor models used in assessing
control strategies and source impacts. Source code and associated
user\'s guides and documentation are routinely provided for
preferred/recommended models, screening models, and alternative models.
In addition, guidance is provided for applying air quality models in
regulatory applications for State Implementation Plans (SIP)
demonstrations and revisions, as well as permit applications for new
source reviews, including Prevention of Significant Deterioration (PSD)
regulations. These latter applications are particularly relevant for
estimating air quality impacts in Indian country.  Also available is the
Model Clearinghouse which is designed to help record the interpretation
of modeling guidance for specific regulatory applications.  Modeling
contacts within the EPA Regional Offices and State environmental
agencies can assist tribes in the regulatory application of air quality
models.  Detailed information on models, codes and guidance in their use
is available at the following Internet addresses:

\-- <http://www.epa.gov/ttn/scram/>

\-- <http://www.epa.gov/scram001/guidanceindex.htm>

\-- <http://www.epa.gov/scram001/guidance_clearinghouse.htm>

**3.10 The NSR/PSD Programs (relationship to monitoring needs)**

The New Source Review (NSR) and the Prevention of Significant
Deterioration (PSD) programs apply to new major stationary sources and
major modifications locating in areas designated as attainment or
unclassifiable for the NAAQS. These programs generally require the
permit applicant to conduct a source impact analysis, using monitored
data and air quality models. For the NSR program, the impact analysis
must demonstrate that the new or modified source will not cause or
contribute to a violation of state or national air quality standards or
cause an adverse impact to visibility in any federal Class I area. The
PSD program is generally designed to provide a more comprehensive source
impact analysis than the NSR program, including effect on air quality
related values, e.g., visibility, that have been identified for Class I
areas. NSR and PSD are major pollutant control programs that should be
of concern to tribes. Coordination of NSR/PSD and the use of air
monitoring data in source impact analyses, to identify existing
(representative) conditions and potential future impacts, should be
addressed by tribes; relevant information is available at the following
Internet addresses:

\-- <http://www.epa.gov/nsr/>

\--
<http://www.epa.gov/ttn/amtic/files/ambient/criteria/reldocs/4-87-007.pdf>

\-- <http://www.epa.gov/ttnamti1/files/ambient/visible/r-99-003.pdf>

**3.11 Benchmarks for Health and Ecosystem Effects**

[General Air Benchmarks]{.underline}. Air Quality indicators,
concentrations of criteria pollutants relative to the NAAQS, effects on
health due to toxic air pollutants, and other ambient measures such as
visibility and acid deposition, all provide benchmarks of the nation's
air quality; these benchmarks are directly relatable to the needs of
tribal programs. The 2003 Report on the Environment makes extensive use
of indicators in assessing the status of health and ecosystem effects;
preparation of a report that reflects 2006 has begun. The Report on the
Environment, and associated information on criteria and toxic air
pollutants, is available at the following Internet addresses:

\-- <http://www.epa.gov/indicators/index.htm>

\-- <http://www.epa.gov/indicators/roe/html/roeTOC.htm>

\-- <http://www.epa.gov/ttn/naaqs/>

\-- <http://www.epa.gov/air/visibility/index.html>

\-- <http://www.epa.gov/airmarkets/cmprpt/arp03/summary.html>

[Air Toxics and the Integrated Risk Information System
(IRIS)]{.underline}. IRIS was prepared and is maintained by EPA as an
electronic database containing information on human health effects that
may result from exposure to various chemicals in the environment. It was
developed in response to the need for consistent information on chemical
substances for use in risk assessments, decision-making and regulatory
activities. The collection of computer files covering individual
chemicals contains descriptive and quantitative information concerning
(1) oral reference doses and inhalation reference concentrations (RfDs
and RfCs, respectively) for chronic noncarcinogenic health effects and
(2) hazard identification, oral slope factors, and oral and inhalation
unit risks for carcinogenic effects. Information on IRIS and other
sources of air toxics information that may prove useful to tribal
programs are available at the following Internet addresses:

\-- <http://www.epa.gov/iris/index.html>

\-- <http://www.epa.gov/ttnatw01/hlthef/hapindex.html>

\-- <http://www.epa.gov/air/toxicair/index.html>

**3.12 National Air Toxics Assessment (NATA)**

NATA is a national-scale assessment of [33 air
pollutants](http://www.epa.gov/ttn/atw/nata/34poll.html) (a subset of 32
air toxics on the Clean Air Act\'s list of 188, plus [diesel particulate
matter](javascript:gloss('gloss.html#diesel'))). The assessment
considers the year 1996 (an update to 1999 is in preparation),
including: (1) compilation of a national emissions inventory of air
toxics emissions from outdoor sources; (2) estimates of ambient
concentrations across the contiguous United States; (3) estimates of
population exposures; and (4) characterizations of potential public
health risks including both cancer and non-cancer effects. The goal of
NATA is to identify those air toxics which are of greatest potential
concern, in terms of contribution to population risk. This information
should also be relevant and useful in assessing risk under Tribal
programs. Results are available at:

\-- <http://www.epa.gov/ttn/atw/nata/>

**3.13 Indoor Air Issues (radon and mold)**

Radon and mold can both be problems in indoor environments. Radon is
odorless and tasteless, but may exist at ambient air levels that exceed
safe limits in homes. Air containing radon that is breathed indoors is
the second leading cause of lung cancer in the United States.  Molds can
gradually damage homes and furnishings and can cause potential health
problems avoided. Internet addresses with additional information on
radon and mold, associated effects, and mitigation strategies available
for consideration by tribes are available at the following Internet
addresses:

\-- <http://www.epa.gov/iaq/index.html>

\-- <http://www.epa.gov/mold/index.html>

\-- <http://www.epa.gov/radon/index.html>

\-- <http://www.epa.gov/iaq/atozindex.html>

**4.Number range CHAPTER Tribal Air Quality Issues, Relevant Air
Monitoring Air Monitoring and Tribal Air Monitoring Activities**

This section will examine the reasons for tribal air quality monitoring
and provide examples of current tribal air monitoring.

Section 301 (d) of the 1990 Clean Air Act Amendments provides federally
recognized tribal governments the authority to implement Clean Air Act
programs for their reservations and other land that they can demonstrate
jurisdiction. The Tribal Authority Rule (TAR) promulgated on February
12, 1998, further delineates the authority of tribes to implement air
quality programs under the Act.

Tribes may need to conduct ambient air monitoring for a variety of
reasons which include the following: (1) attainment with health and
welfare based National Ambient Air Quality Standards (NAAQS); (2)
impairment of visibility and biological diversity for vistas within or
near reservations; (3) measurement of toxic air pollutants for health
and ecological effects; (4) collection of near-real time data for
reporting Air Quality Index (AQI) to the tribal community and to EPA's
AIRNOW real-time mapping program, (5) monitoring air quality related to
tribal environmental and cultural resource concerns, (6) being part of a
Regional/State monitoring network (7) for determining air quality
background levels and establishing air quality baselines and (8) to
increase awareness that indoor environments play a large, if not the
largest, role in causing the increase in asthma and respiratory disease.

Tribes have a need to understand the short and long term effects of long
distance transport on tribal lands and the effects of atmospheric
deposition on the ecology of their lands. Tribes also need air
monitoring data to identify the role of off-reservation sources and /or
to build a case or partnership for controlling those sources. Examples
of these programs include long term IMPROVE, NADP, MDN, ozone, PM2.5,
precursor gas and toxic air quality monitoring.

The following is a review with examples of how the tribes have conducted
air quality monitoring to provide data: (see appendix?? for more
detailed examples of specific air monitoring)

> **4.1 Air Monitoring for Compliance with Health Based NAAQSs**

Tribes are currently monitoring to demonstrate compliance with national
standards, primarily for ozone and particulate matter, in areas of the
country that are not in compliance with the NAAQSs for these pollutants
or have no existing monitoring. The data from these sites may be used to
demonstrate the need to develop a tribal implementation plan, to show
the inadequacies of state or federal implementation plans (or monitoring
networks) or to warn tribal members of unhealthy air quality. Tribes may
also be well located to perform air monitoring that broadens the
coverage of state SIP monitoring networks. For example, several tribes
in Regions 1 operate ozone and PM2.5 air monitoring sites in areas that
the states are unable to monitor, such as the island of Martha's
Vineyard, MA or far eastern ME.

An example of this type of air monitoring is the ozone air quality
monitoring being performed is the Wampanoag Tribe of Gay Head at
Aquinnah, MA (Martha's Vineyard). The tribe is currently operating an
air monitoring program consisting of an ozone monitor, an IMPROVE
sampler, and a meteorological station. The station is located in the
Massachusetts non-attainment area in an area where there is no state air
monitoring. In 2005 the station recorded four days above the 8-hr. ozone
NAAQS and provided the tribe with health related air quality data to
inform tribal members. Data from this station will also provide the
tribe with the ability to ensure that ozone air quality standards will
be met in the future.

PM10 monitoring has been on-going in non-attainment areas on Tribal
lands in Montana for many years. The Confederated Salish and Kootenai
Tribes and the Northern Cheyenne Tribes were designated non-attainment
for PM10 in 1989. Ongoing monitoring for PM10 will be required to
satisfy compliance with their respective Tribal Implementation Plans.
PM2.5 monitoring was also initiated in these two areas as a screening
tool to ensure compliance with the PM2.5 standard.

> **4.2 Impairment of Visibility for Vistas within or near
> Reservations**

Visibility measurements are another important measurement objective for
tribal reservations designated as Federal mandatory Class 1 areas or in
areas where regional haze is of concern. The CAA amendments of 1990 set
a target of improving visibility in mandatory Class 1 Areas to natural
visibility conditions by 2064. Data from these sites will provide tribes
important information to determine the impacts from regional haze on
visual impairment on tribal lands. Examples of visibility measurements
on tribal lands include the operation of IMPROVE monitors by a number of
tribes and the operation of haze-cameras on tribal lands. The Aroostook
Band of Micmac Indians operate both an IMPROVE monitor and a haze camera
at their air monitoring site in Presque Isle Maine. Data from this site
is included in the National IMPROVE web page and the haze camera is
included as part of the NESCAUM haze-cam network. The Assiniboine and
Sioux Tribes of the Fort Peck Indian Reservation in northern Montana
also operate an IMPROVE monitor which they use to monitor the status of
their voluntary Class 1 air shed. They, the Confederated Salish and
Kootenai Tribes, and the Northern Cheyenne Tribes operate IMPROVE
samplers that supplement the core IMPROVE network and provide valuable
information on areas that would otherwise lack monitoring resolution.

**4.3 Toxic Air Pollutants for Health and Ecological Effects**

Tribes are also monitoring for hazardous air pollutants and/or air
toxics. Air monitoring for these pollutants can either be for short term
exposures when there is a chemical release or for long term community
and ecological impacts. Sources of these pollutants include nearby
stationary sources, area sources, mobile sources, and long distance
transport from urban areas. Data from these sites provide the tribes
critical information on hazardous pollutant exposures and impacts of air
toxics on communities and tribal lands through risk analyses conducted
using this monitoring data. Examples of this type of monitoring include
mercury deposition monitoring or the impact of a nearby power plant or
pulp mill. The Nez Perce Tribe of Idaho is currently conducting air
toxics monitoring in the town of Lewiston and on their reservation for
toxic emissions from the Potlatch pulp mill in Lewiston. Several tribes
in Maine conduct monitoring for metals and mercury deposition for long
term trend data on their tribal lands. In addition several New England
Tribes are collecting and analyzing fish tissue data both as a measure
of fish contamination and as an indicator of mercury deposition.

**4.4 Monitoring to Support AQI and AIRNow**

Some Tribes are operating continuous monitoring for ozone and PM2.5 and
convert these data to the appropriate AQI, based on EPA's AQI concept.
This AQI relates concentration of pollutants to their potential health
effects and can be used to alert a community to unhealthy air quality
conditions. Another critical role for tribal monitoring is being part of
the national AIRNOW mapping program. These sites provide near real-time
data quality information and valuable information to better understand
the fate and transport of air pollution. The data is also valuable in
providing data to improve the mapping programs in rural area where there
is little or no state data.

> **4.5 Significant Air Quality Related Environmental and Cultural
> Resource Concerns**

One of the most important reasons that tribes are conducting air quality
monitoring is to gather information on the long term air quality effects
on the tribal community and on tribal lands. In many cases tribes use
their ancestral lands for subsistence hunting and fishing, traditional
rites, and harvesting native plants. Tribes are concerned that long term
exposures to air pollutants, acid rain, and heavy metal deposition will
adversely affect these resources. It should be noted that this type of
air monitoring requires a long term commitment both in term of funding
and in resources (for operation of equipment and analyses/assessments of
the data). Examples of this type of monitoring include operating trace
level SO2, CO and NOy monitors, sulfate, nitrate, metals, and NADP & MDN
samplers and IMPROVE samplers~~.~~

**4.6 Regional Monitoring**

Another critical role for tribal monitoring is being part of a
Regional/State monitoring network. Tribes may be well located to perform
air monitoring that broadens the coverage of state SIP monitoring
networks and supports the national AIRNOW mapping program. Several
tribes in Regions 1 operate ozone and PM2.5 air monitoring sites in
areas that the states are unable to monitor, such as the island of
Martha's Vineyard, MA or far eastern ME. Not only do these sites provide
extended coverage for the regional air monitoring program, but also they
provide improved coverage for EPA's AIRNOW real-time air quality mapping
program. These sites provide valuable information to better understand
the fate and transport of air pollution.

> **4.7 Determining Air Quality Background Levels and Establishing Air
> Quality Baselines for PSD**

In some cases tribes will need to conduct air quality monitoring to
determine air quality background levels or to establish a baseline. This
information is important for the protection of areas with pristine air
quality and to provide quantitative data before new stationary sources
are located in or near Indian Country.

**4.8 Indoor Air Quality**

The increase in asthma and respiratory disease, and the attempt to
discover their causes has led to an increased awareness that indoor
environments play a large, if not the largest, role in causing this
issue. Molds, tobacco smoke, Radon, improper ventilation, insect
infestations, and cooking/heating fires all play a role in increasing
the effects of respiratory distress on effected populations and to a
disproportionate extent the tribal members. Funding for monitoring
projects such as the Radon monitoring program, Tools for Schools, and
others, can be used to assist in identifying problems and suggest
solutions. This information can be used to act or can influence other
mechanisms to assist in remediation of Indoor Air Quality issues.

**4.9 Source Monitoring**

Tribes may need to conduct emission monitoring on their major point
sources for compliance purposes. This may be in the form of stack tests
or by conducting continuous emission monitoring. Normally source
monitoring is conducted for particulate, sulfur dioxide, nitrogen
oxides, volatile organic compounds and/or carbon monoxide. ***(Please
send in examples of tribal source monitoring projects)***

# 5. Implementation of Monitoring

There is a growing movement in the United States of Tribal agencies
taking an increased interest in ambient air quality issues on Tribal
lands.

Tribes wishing to examine ambient air quality issues on their
Reservations or Tribal lands should have a strategy in place as they
develop their work plan and program strategy. Tribal agencies often
decide that the best way to assess the current air quality situation is
through the use of ambient air quality monitors. A strategic approach to
monitoring should incorporate specific planning stages so that
monitoring time and money is spent wisely. Consideration of the
following sections will help Tribes plan and carry out an appropriate
strategy.

**5.1 Objectives**

The type of air monitoring sampler to be used should depend heavily on
the monitoring objectives the Tribe has developed concentrating on what
they want the data to provide. Such reasons might include, but are not
limited to:

-   To determine the location and levels of the highest concentrations
    expected to occur in the area covered by a monitoring network
    (potentially to establish official status as
    attainment/non-attainment)

-   To determine concentrations that are representative of longer
    averaging periods or a broader geographic area

-   To assess potential toxic hot spots

-   To assess visibility

-   To ensure protection of PSD increments

-   To determine impact on ambient pollution levels of significant local
    source categories

-   To determine baseline concentration levels (to compare to future
    levels to measure changes and try to determine source of changes)

-   To study pollutant transport issues in order to understand how the
    tribal area is being impacted by upwind sources and what those
    sources are

-   To assess mercury and other persistent bioaccumulative toxics (PBT)
    deposition

-   To develop control strategies

-   To perform model validation

-   To aid in public air quality reporting and forecasting

Four important questions should be considered by the Tribe before
monitoring begins:

1)  Why are we monitoring?

2)  What are we monitoring?

3)  Who in the tribal organization will watch the results as they come
    in, and how?

4)  What could our response or plan be if our monitoring data indicates
    unhealthy conditions?

Tribes need to consider what purpose the data collected will be used
for. Validated, defensible data may be needed for applications such as
attainment/non-attainment designation purposes. If a Tribe wishes to
make such a designation, a Federal Reference Method (FRM) or Federal
Equivalent Method (FEM) monitor must be used for the pollutant of
concern. These are monitors that have specifically been approved by the
EPA to use for assessing compliance with the National Ambient Air
Quality Standards (NAAQS) for that pollutant. If a tribe is not
monitoring to demonstrate compliance, other types of monitors could be
used. For example; the type of PM filter samplers used in the IMPROVE
program, a TEOM-based continuous PM monitor, or passive badge-type ozone
monitors. These types of monitors have not been approved by EPA for
compliance purposes but are still considered to be a viable form of
monitoring. A Tribe might choose one of these unofficial monitors over
an FRM or FEM based on ease of operation, cost, simpler access to
laboratory services, or other reasons.

Tribes should be aware that data collected with federal money, such as
EPA grants, is considered to be in the public domain and EPA's
expectation is that eventually the data will be accessible to the
general public. Data collected during a limited start-up period while a
Tribe is still working out problems can be an exception if agreed to
with the EPA Regional Office. If a Tribe wants to keep data
confidential, it cannot be collected using federal funds.

**5.2 Pollutant Selection**

The Tribe should research a complete list of technical information
resources on local, regional and even national levels depending on the
pollutant of interest and type of monitoring incorporated. A Tribe can
identify which pollutants are of the greatest concern through existing
methods and tools such as:

-   EPA Air Quality System (AQS): A national database that tracks air
    monitoring data from state, local, tribal, and other entities

-   Toxic Release Inventory (TRI)

-   Other tribes and tribal consortiums who have their own monitoring
    programs

-   Data from existing programs such as Interagency Monitoring of
    Protected Visual Environments (IMPROVE), Clean Air Status and Trends
    Network (CASTNET), National Atmospheric Deposition Program (NADP),
    etc.

-   State and Tribal Emission inventories (many tribes do their own
    inventory prior to making monitoring decisions)

-   Private industry monitoring data

-   Climatology data

-   Observations from other environmental programs within the same tribe
    (i.e. water quality, forestry, wildlife management)

-   Federal Land Managers

-   Regional Planning Organizations - Central Regional Air Planning
    Association (CENRAP), Western Regional Air Partnership (WRAP),
    Visibility Improvement State and Tribal Association of the Southeast
    (VISTAS), Mid-Atlantic/Northeast Visibility Union (MANE-VU), Midwest
    RPO, etc.)

In correlation with the data, the type and need of monitoring should
also focus on the category of source. The category of source will help
determine what method of monitoring should be utilized and if it is
worth pursuing. Categories can be broken down as follows:

-   Stationary or Point (please see SCC codes for full list)

    -   Factories

    -   Power Plants

    -   Chemical Process Industries

    -   Petroleum Refineries

-   Area (please see AP-42, Chapter 13)

    -   Dry Cleaners

    -   Road Dust

    -   Gas Stations, Auto Body Shops

    -   Woodburning Stoves, Burn Barrels

    -   Crop Burning/Prescribed Burning

-   Mobile (please see AP-42, Chapter xx for full listing)

    -   On-Road

        -   Trucks (Semi tractors/trailers)

        -   Buses

        -   Cars

    -   Off-Road

        -   Farm vehicles

        -   Construction Equipment

        -   Trains

        -   Recreational Vehicles (Boats, ATV's, Snowmobiles, etc.)

Tribes can assess the risks that different pollutants pose by studying
unit risks and reference concentrations. This information is available
on EPA's website (National Center for Environmental Assessment (NCEA) ,
Integrated Risk Information System (IRIS), Technology Transfer Network
-- National-Scale Air Toxics Assessment) . The EPA has its own
assessment group called the Risk Assessment Forum, made up of senior EPA
scientists. This forum "was established to promote Agency-wide consensus
on difficult and controversial risk assessment issues and to ensure that
this consensus is incorporated into appropriate Agency risk assessment
guidance". Tribes should be aware that the scientific understanding of
these pollutants may change over time, as more data becomes available.
Also, different organizations and experts can have different assessments
of these substances. Tribes should make sure they are looking at data
from credible sources.

Tribes that are considering monitoring or that are already conducting
monitoring are encouraged to watch for proposed changes in the NAAQS or
scientific data on health risks with regard to the pollutant of
potential concern. For example, if a NAAQS standard were to be lowered
for PM10 (or any other criteria pollutant that was being monitored for)
because new evidence indicated the adverse health impacts suspected were
no longer an issue, then the tribe would want to re-evaluate the purpose
of the monitoring and consider whether it is still necessary. To keep
abreast of changes in the standards, tribes can use a variety of
sources. Information is often available through the National Tribal Air
Association (NTAA), through EPA outreach efforts, through Regional
Tribal Operations Committees (RTOC), or on EPA's Ambient Monitoring
Technology Information Center (AMTIC) website.

**5.3 Monitor Selection**

Once the pollutant parameter (or pollutant wished to monitor for) has
been identified, the sampling methodology should be decided upon. The
final decision on what type of monitor to use will focus on many factors
such as (but not limited to): cost; accuracy; level of tribal monitoring
experience; seasonal conditions; expected program continuity; the need
to monitor for one or multiple pollutants; monitor maintenance/service
requirements; and conditions at monitoring site (electricity and phone
line availability). Ambient air monitors can be broken down into two
general groups, manual and continuous:

-   Manual Samplers

    -   Time averaged data

    -   Sampling Media

        -   Filters, Cartridges, Canisters, Precipitation samples

    -   Analyzed in separate step in a qualified laboratory

    -   Most do not need a shed or trailer, may need shade

-   Continuous Samplers

    -   Instrumental methods (clarify)

    -   On-line data (clarify)

    -   Continuous data stream

    -   Most or all need a shed or trailer

This step is a difficult and important one. For example, many Tribes are
involved in particulate sampling. They may choose to deploy a couple of
manual PM~2.5~ samplers in an area of their Tribal land. This will
require an operator to collect the filters to have them analyzed by a
lab. The Tribe may choose a continuous PM~2.5~ monitor, which will
involve a data logger to record readings and can be downloaded from a
modem to a remote site. However, a continuous monitor may be more
complex and may require a shed or trailer and more maintenance. Or the
Tribe may choose to use mini-volume samplers which are more portable and
can be used in a mobile status but do require laboratory analysis.
Tribes can obtain laboratory services to weigh PM filters from TAMS
without charge, or for a fee (payable from EPA grant funds) from the
IMPROVE program or from national contracts administered by EPA. The
Tribe may want to host monitoring sites in existing national programs,
such as the National Atmospheric Deposition Program/Mercury Deposition
Network (NADP/MDN) and CASTNET, which offer assistance in all areas of
operation. In these program a Tribe would typically contribute staff
time for site operation and maintenance but the national program would
pay for laboratory analysis and/or program costs. Before joining a
national program, the Tribe should make sure that the program is a good
match for the Tribe and that the monitoring objectives of the program
are similar to the Tribe's.

Tribes are strongly encouraged to collect meteorological data at the
monitoring site. Usually a minimal station measures wind speed and
direction, relative humidity, temperature, barometric pressure, and
precipitation, and uses a data logger for gathering and storing data.
This involves purchasing and operating additional pieces of equipment.
There are standard procedures for submitting meteorological data to the
AQS and/or AIRNOW data systems so that the Tribe and others can access
it.

**5.4 Siting**

A monitoring site should be chosen based on what information the tribe
wishes to capture and the objectives described in Section A. Some
Reservations are so large that monitors are needed in multiple locations
or a Tribe may wish to place multiple monitors in order to study
transport issues. Multiple monitors for different pollutants may be
placed at the same site, which provides a more robust data set for
understanding what is happening to air quality and why. Needless
redundancy in monitors at one site should, of course, be avoided.

A site should be chosen with consideration for the following concerns.
The site should be in a location where data collection objectives can be
addressed (i.e. close to a school, close to a certain source, rural for
background levels, etc). Each monitor has set criterion for siting to
make sure that it monitors real ambient air. This should be investigated
for each monitor before a purchase or site is decided upon. Most
importantly, monitors need to be situated a certain distance away from
trees or other tall obstructions, such as buildings, and the monitor
probe needs to be situated a certain distance above the ground. The site
should be easily and safely accessible by staff, should allow for
electrical and phone hook-up, or solar power if feasible, and should
minimize opportunities for vandalism. The site should be accessible
year-round, through spring rains and winter snowfalls, and should allow
for location of a shed or trailer, if needed. It is useful for the site
to be accessible by a vehicle carrying equipment and gases needed for
quality assurance audits.

Because many Reservations are located in rural areas, impediments may
exist to running electrical or phone service to site locations. Tribes
are encouraged to look at alternative solutions, such as radio,
satellite, or Internet-based communications systems and generator, wind,
or solar-derived power.

Depending on the type of monitor chosen and the local climate, a
monitoring shed or trailer that is weather-tight,
temperature-controlled, and has adequate space may be needed. If a
trailer is not available, shed kits can be purchased locally. The Tribe
should consider future monitoring needs when arranging for a shelter so
that extra space and adequate power sources are available.

Tribes should consider the timing involved in installing a monitor. For
example, a grant received in late summer may result in monitors being
placed the following spring. Time is needed to receive the grant money,
order the monitor, prepare the site, write the QAPP, contract laboratory
analysis, and learn how to operate the monitor. These steps can take
months and can be slowed by weather conditions.

**5.5 Funding**

Once a Tribe has identified pollutants of concern, found a site, and has
chosen a specific monitor funds should be sought. Initially, a Tribe may
choose to work with their EPA regional contacts to begin development of
a work plan, which will be required in order to receive EPA funds and
will be used to organize the direction of the air program. This is
especially important in the planning phase as many of the air monitoring
development steps can be incorporated into the work plan objectives and
thus funded by EPA. This also obligates EPA to provide guidance and
technical assistance throughout the whole process.

The EPA offers ambient air funding under Sections 103 and 105 of the
Clean Air Act. Section 103 grants are for air program planning and
short-term projects while Section 105 grants are for operating an
ongoing air program and for long-term projects. Section 103 grants have
the advantage of not requiring the Tribe to match any of the federal
funds, while Section 105 grants require a Tribal match of between 5% and
40% of the total amount of the grant. Further information on Tribal
match requirements can be found in Section 10 of this document or 40CFR
§ 35.575 or 40CFR § 49.4{q}. A Tribe should start out with a 103 grant
and can then apply for 105 funding after the air program has been
established. Tribes can also perform some air-related activities under
EPA's General Assistance Program (GAP).

Other funding options are also available to tribes and should be
explored. As more Tribes apply for EPA air grants, competition has
become tighter. In addition, EPA's budget is not growing and may shrink
in the future. This means that tribes may have to look at alternate
funding sources. Creative opportunities can be found for Tribes to link
their interests to those of other organizations. For instance, National
Oceanic an Atmospheric Administration (NOAA) grants could be awarded for
Tribes to obtain meteorological data that is of interest both to NOAA
and the Tribe. A United States Department of Agriculture (USDA) --
Concentrated Animal Feeding Operations (CAFO) grant could be obtained to
fund ammonia monitoring (of interest in regional haze considerations).
Indian Health Services (IHS) may fund monitoring if it is believed that
air emissions are directly causing health problems on the Reservation.
These are just a few suggestions for places where Tribes can look for
funds.

As mentioned in Section A, the desire to keep data confidential may also
lead tribes to pursue other alternatives. Some tribes pay for their
monitoring using tribal funds. Other Tribes have obtained monitoring
money through Regional Planning Organizations (RPOs) to collect
monitoring data beneficial to both the Tribe and the RPO. Some Tribes
work with state agencies to share monitoring costs and responsibilities
and then share the data with the state agency. Some air-related
activities can coincide with other federal grants. For example, a
meteorological station could serve to gather air-quality data and could
also gather data for alternative wind energy feasibility studies under a
Federal Energy Resources Commission grant.

Before any kind of funding request can be made, cost information must be
collected for the monitor and for ancillary costs. Ancillary costs vary
widely with the type of monitor needed and where it will be located.
These may cover: construction of a monitoring shed or purchase of a
monitoring trailer; installation of electricity and phone service (these
costs may be considerable in rural areas); purchase of a data management
system; lab costs; purchase of calibration devices; spare parts for
monitor; tools for working on the monitor; shipping costs to the lab;
and lab services themselves [^3]. If the Tribe is becoming part of a
program, such as IMPROVE, many of these costs will be combined into an
annual program fee. Some monitors and/or calibration equipment are very
complex and must be shipped back to the vendor for servicing, so these
costs should be considered. Vendors often offer services to visit the
site and install more complex monitors and provide training sessions to
Tribal staff. Though this may be costly, the Tribe may want to consider
this option. A dedicated computer, palm, or laptop may be purchased for
downloading data, analyzing it, and uploading it to various databases or
websites.

Tribes may attend training courses to prepare for monitoring. The
Institute for Tribal Environmental Professionals (ITEP) and the Tribal
Air Monitoring Support (TAMS) center offer courses including: air toxics
monitoring; meteorological monitoring; writing a QAPP; dataloggers; air
quality computations; data management; PM monitoring; ozone monitoring;
Tribal Emission Inventory Software Solution (TEISS); and EPA's Air
Quality System (AQS). Tribes should consider which of these courses they
may want to attend and plan for travel costs.

**5.6 Quality Assurance/Quality Control**

Depending on the Tribe's objectives (see Part A of this section) the
data obtained must be quality assured to an acceptable level. Data is
useless if the Tribe is unable to show that it was collected properly
(i.e. verifiable and defensible). Data collected for designation
purposes is going to be held to a higher standard than data collected
for informational purposes, however in any case a Quality Assurance
Project Plan (QAPP) and Standard Operating Procedures (SOPs) will be
needed, along with regularly scheduled audits, verifications, and
calibrations.

The most important step in a quality assurance/quality control (QA/QC)
program is learning to operate and service the monitor properly. ITEP
courses are available for some types of monitors but not all. Some
vendors offer regular training courses at their facilities or offer
services to set up the monitor and train the staff for a daily fee plus
travel costs. Neighboring tribes, tribal consortiums, or state or local
agencies may also offer assistance. If a Tribe is a member of an RPO,
arrangements might be made for some training. Federal agencies such as
the Forest Service and Park Service sometimes operate monitors and may
be able to offer assistance.

The Tribe must prepare a QAPP and SOP's for all monitoring activities.
This can be a months-long process, depending on the complexity of the
monitor and the purpose the Tribe will be using the data for. Once the
Tribe has finished writing the QAPP, it is submitted to the Regional
Office for approval. Although QAPPs are supposed to be written and
approved before any data is collected, this may be unrealistic for
tribes. It is hard to write a QAPP for a monitor one has never seen or
operated. Although QAPPs may be copied from another tribal or state
agency, the operation of the monitor still needs to be understood by the
Tribal operators because the operators must follow the QAPP on a daily
basis. Ancillary equipment also needs to be understood for proper
operation and maintenance. Weather instruments, data loggers, electric
surge protectors, and associated computers fall under this category.

The EPA's OAQPS is working with ITEP to develop a generic ambient air
monitoring QAPPs software product. This product is planned to be
available in September of 2006. The EPA is also considering the
implementation of a Quality Assurance certification program in its draft
National Monitoring Strategy. This program would establish a national
accreditation process to certify QA personnel. Although participation
would not be mandatory, the program would help foster consistency in
training and QA requirements across the nation.

Calibrations of all equipment at the monitoring site must also be
scheduled regularly. Calibrations test the monitor's response at a
number of data points and at a zero point. Calibrations are performed
for any of the following reasons (not an exhaustive list): initial
instrument installation; instrument Zero/Precision/Span drift tolerances
are exceeded; maintenance or repairs affect calibration; instrument is
physically relocated; instrument has not been calibrated within 3
months. Calibrations can be performed by Tribal staff and are required
regularly enough that this is the most efficient scenario. A Tribe can
also hire a contractor.

Zero/Span/Precision (ZPS) checks are performed on some continuous
monitors. These instruments are subject to drift and variation in
internal patterns over time as part of their normal operation. The
calibration relationship between what the instrument is reading and the
true value of what it is measuring must be checked periodically through
ZPS checks. These checks are done very routinely and it is probably best
for Tribal staff to learn to perform them. Learning these techniques
will help with learning to do calibrations and general maintenance.
Procedures can be found in the instruction manuals that come with the
monitor or can be copied from other state or tribal agencies.

Field blanks are used to assess contamination that might occur as a
result of inadequate sample container preparation, or contamination that
may occur during shipping or handling in the field. Blanks are used only
for physical samples sent for laboratory analysis.

Tribe must schedule regular audits, which are formal detailed studies of
one or more aspects of a project conducted by independent auditors.
Audits study specific criteria previously determined by the site manager
to be critical to the success of the project and test a monitor's
response to a known input. There are system audits and performance
audits. Performance audits check how far "off" a monitor's response is
from its input and checks the slope of a best-fit line. The system audit
tests the gas standards used for calibrations, spans, and precision
checks; shows that the data pass validity tests concerning completeness,
reasonability, span limits, and precision points; verifies siting
criteria; and ensures that recommendations from previous have been
implemented.

EPA audit guidelines and requirements can be found in guidance documents
for each specific pollutant. Auditing equipment needs to be completely
independent of equipment used for routine calibration and QC checks on
the equipment. Audit criteria should be included in a Tribe's QAPP so
the Tribe can assess when a monitor has passed an audit and when it has
not.

In each EPA Region, EPA employees have designed monitoring trailers and
conduct traveling audits each summer for tribes in those regions
(Regions 1 and 2 share a trailer). Audits can also be performed by other
Tribes, TAMS staff, state agencies, or by contractors. A Tribe may even
consider contracting out the entire operation of a monitor, although
these costs may be prohibitive and contractors may not have the same
dedication or interest for the project as the Tribe. In addition,
learning how to plan, implement, operate and maintain a monitoring
network is often believed to be a crucial part of Tribal
capacity-building.

The EPA also requires Tribes to write Quality Management Plans (QMP's),
which cover the operation of an entire office. The EPA looks at a
Tribe's QMP along with its QAPP's when awarding funds.

**5.7 Data Management**

During and after the data collection process, Tribes need to handle the
data they produce. Continuous monitors collect large volumes of data
that need to be recorded as it is generated. Data from all types of
monitors needs to be stored until it can be reviewed and quality
assured. Once the data is quality assured, it needs to be corrected,
flagged as necessary, and placed in a repository where other interested
parties can view it. Since this document contains an entire section
(Section VIII) devoted to data storage and access, we will offer only a
short synopsis here.

ITEP offers Data Analysis courses where Tribes can learn basic
statistical techniques used for demonstrating compliance with the NAAQS.
Certain data needs to be uploaded to the EPA's AQS or AIRNOW databases
if funded with EPA grants. Some Tribes place their data on a website so
Tribal members can access it on a day-to-day basis. A number of tribes
work with state agencies or RPO's and offer their data on those
agencies' websites.

**Refer to the independent multi-tribe real time data system that is
similar to Texas's. Tim Hanley can describe it???**

Part of data management involves site and instrument logbooks where
information and results are recorded manually. A site logbook should be
kept to detail maintenance activities, problems at the site and how
these problems were corrected. For example, power outages and equipment
failures need to be noted. In addition to a site logbook, a separate
logbook should be kept for each individual monitor to record the results
of calibrations and other procedures. Logbooks serve as the
"institutional memory" of a site or monitor and can help staff members
remember when a specific problem occurred and how it was addressed.

**5.8 Data Access**

One goal of collecting monitoring data is to allow the general
population to see monitoring data as soon as it is processed and
quality-assured. Sensitive individuals can then choose to limit their
physical activity if pollution levels are high. Data can be useful to
other groups who are studying air pollution for scientific or
policy-setting purposes. All data gathered using federal funds should to
be sent to the EPA so it can be included in national databases. Some
tribes also choose to use their own website to make data available to
their constituents. Other tribes work with other agencies or contractors
to disseminate their data.

**Refer to the independent multi-tribe real time data system that is
similar to Texas's. Tim Hanley can describe it???**

**6. How to Request EPA Funding and Other Support**

Air quality monitoring activities may qualify for a variety of EPA or
other agency grant support depending upon its context, purpose and other
factors. Within EPA grant funds may be available for monitoring air
pollution levels through appropriations made for the Indian General
Assistance Program (IGAP) from the American Indian Environmental Office,
for tribal projects and program implementation under the Office of Air
and Radiation, through the Direct Implementation Tribal Cooperative
Agreement mechanism to assist EPA with implementation of the CAA within
Indian country, or a variety of other miscellaneous grant opportunities
available to a variety of organizations, including tribes, such as for
air toxics projects, environmental education, and community projects
that can vary from year to year. Other agencies that may fund monitoring
include the Bureau of Indian Affairs, nonprofit groups, and
foundations..

EPA provides a variety of tools, guidance and references that tribes may
access through the web to develop proposals and workplans to submit for
grant funding. Many of these sites can be found through the links
available at: [http://www.epa.gov/ogd/]{.underline}.While there is some
consistency across the agency on what the criteria will be for funding,
each Region also may have its own specific criteria and procedures, as
well as deadlines that must be complied with in order to increase an
applicant's chances of receiving financial support.

On the OAR Tribal Air Website additional information and assistance can
be found, including the Tribal Air Grants Framework: A Menu of Options,
which was designed especially for tribal air grantees and EPA Project
Officers to assist them to be able to effectively develop and manage
these grants for environmental results. This can be accessed at:
<http://www.epa.gov/air/tribal/pdfs/menuofoptions.pdf>**.** Within this
Framework are at least two Menu items that may assist tribes who are
seeking grant funding in order assess or monitor their air quality,
along with a variety of others for other types of air-related work
activities.

The two most relevant Menu items are: ***The Menu Item for Conducting a
Basic Air Quality Assessment***, and ***The*** ***Menu Item for
Conducting Air Quality Monitoring.*** The former will assist an
applicant in identifying the activities that will assist in documenting
whether there is a need for monitoring or whether some other activity
may be more appropriate to address an air quality concern. The latter
provides some of the activities that can be considered for inclusion in
a workplan for conducting air quality monitoring. Both have examples of
applicable Objectives, Outputs, and Outcomes, as well as examples of how
EPA may measure national accomplishments in this area.

Assessment and baseline air quality monitoring is typically eligible for
funding through the IGAP program. The Regional Tribal Office can provide
more specific information on the requirements for this funding.
Assessment and baseline, as well as regulatory, monitoring can be funded
under Clean Air Act authority or OAR grant resources. For details on the
CAA 103 or CAA 105 authorities and the Direct Implementation Cooperative
Agreement funding mechanisms and how a tribe may qualify for this
funding, the EPA Regional Office of Air's Tribal Coordinator can provide
specific information.

**7. Storage and Access to Monitoring Data**

**7.1 Problem Statement**

Tribes collect environmental data principally for internal use so tribal
leaders can make informed decisions to accomplish their environmental
policy objectives. Historically, EPA has required tribes in some Regions
to submit data to the Air Quality System (AQS) as a deliverable for
their Clean Air Act related grants. Not all EPA Regions have required
tribal data to be submitted to AQS. Recently, there has been a push by
EPA for all tribes to submit their data to AQS in all EPA Regions.

Many tribes have argued that forcing them to submit data to AQS is an
infringement on their inherent tribal sovereignty. Others have argued
that it isn't stated in the Tribal Authority Rule that tribal data must
be submitted to a national database, and the new requirement is policy,
not law. There is a link between tribal sovereignty and data collected
on tribal lands, and some tribal governments are expressing significant
reluctance to being forced to submit data to national databases, such as
AQS. Policy relating to tribal AQS data submittal should carefully
consider tribal concerns and include dialog with tribal leaders at the
highest levels of government.

There is also a "right to know" aspect in US public environmental
policy. Both tribal and non-tribal US citizens live within the tribal
environmental jurisdictions as defined by the Tribal Authority Rule of
the Clean Air Act, and policies developed and implemented within Indian
country can also impact neighboring jurisdictions. This complicates the
issue of tribal sovereignty as it relates to public access to
environmental information. This is especially true for environmental
data gathered through federal funding. These are also things that need
to be considered.

As previously stated, several tribes currently submit their data to AQS.
There are other tribes that are very open to submitting data to AQS in
principal, yet the resources to accomplish the task are limited.
Technical staff within tribal nations are frequently tasked with
multiple duties. This sometimes requires one person to develop and
utilize technical expertise in virtually every aspect of implementing
the Clean Air Act within their jurisdictions. The time they can spend
submitting data to AQS is limited. Since this is an infrequent task,
usually only required on a quarterly basis, it can also be a difficult
task to master. New resources to assist with AQS data submittal may be
necessary. Presently there isn't a single person anywhere in the US
whose sole job is to assist tribes with AQS entry.

Historically, some tribes relied heavily on various consultants to enter
air monitoring data into AQS on their behalf. However, since there is
currently less funding available from EPA to the tribes, the
responsibility has now been shifted back to the tribes to submit their
air monitoring data into AQS themselves. While it is true that some
regional EPA offices have been entering tribal raw data into AQS for a
few tribes, there is a push to limit regional assistance by training
tribal air quality staff so they may resume responsibility of entering
their own data into AQS.

**7.2 Description of AQS for Tribal Needs**

The Air Quality System (AQS) contains ambient air pollution data
collected by EPA, state, local, and tribal air pollution control
agencies from thousands of monitoring stations.  AQS also contains
meteorological data, descriptive information about each monitoring
station (including its geographic location and its operator), and data
quality assurance/quality control information.  So far, 27 tribes submit
their own data into AQS, while 14 tribes have others such as EPA
Regional offices, states or contractors submitting their data into AQS.
Currently there are 7 tribes submitting data using the new tribal code.

**7.3 Getting Data into AQS**

EPA regulations require state/local/tribal environmental agencies to
report air monitoring data at least quarterly. Data for one calendar
quarter are due to EPA by the end of the following quarter. However,
some values may be absent due to incomplete reporting, and some values
subsequently may be changed due to quality assurance activities. Today,
States, Local and Tribal agencies submit their data directly to AQS via
a web application. Users will need access to the internet in order to
access AQS. Registered users may also retrieve data through the AQS
application and through the use of third party software such as the
Discoverer tool from Oracle Corporation.  In the future, data from AQS
will be available via the AQS Data Mart that will be in production late
spring 2006.

**7.4 Who has Access to Data Once Submitted to AQS**

The Office of Air Quality Planning and Standards (OAQPS) and other AQS
users rely upon the system data to assess air quality, assist in
Attainment/Non-Attainment designations, evaluate State Implementation
Plans for Non-Attainment Areas, perform modeling for permit review
analysis, and other air quality management functions.  AQS information
is also used to prepare reports for Congress as mandated by the Clean
Air Act.

> **7.5 How AQS can be used to Retrieve Tribal Monitoring Data in Useful
> Forms**

OAQPS modified AQS to allow the use of tribal codes in the place of
state/county codes for data loading and retrieval. This change allows
tribal users to submit and retrieve tribal data without using a
reference to geo-political FIPS State and County codes, and thus
reinforce EPA's commitment to recognizing tribal sovereignty. Should any
tribe (or any user for that matter) need assistance or help loading or
retrieving data, AQS has user support which is provided through the EPA
Call Center. There is a toll free number (866-411-4372), and e-mail
(epacallcenter@epa.gov) that users may use to get help with the AQS
application. This helpline covers all aspects of AQS, i.e., simple
questions such as changing passwords to modifying reports to retrieve
specific data or change/correct monitoring data. Also EPA's ten regional
offices each have an AQS representative that can assist tribes in using
AQS. There is also training available at the annual AQS conference that
tribes can take advantage of during the conference.

**8. Understanding Monitoring Data and Its Implications**

**8.1 Background**

There are many approaches to data interpretation ranging from a simple
data summary to complex statistical procedures. The range of
possibilities can be overwhelming, but is easily narrowed by asking a
simple question: "Why was monitoring conducted in the first place?" The
appropriate use of monitoring data is intimately linked with the
monitoring objective. Assuming that the monitoring agency has followed
the procedures outlined in previous sections of this document, the
existing or proposed monitoring plan has a purpose in mind and steps
have been taken to ensure that the final data product is adequate for
its intended purpose.

For example, an agency located in a potential high ozone area may set up
an ozone monitor to gauge attainment of the National Ambient Air Quality
Standard (NAAQS). Quality assurance measures must be put in place to
collect reliable data for a 3-year period. If the dataset is found to
meet data quality objectives then it may be used as the basis for NAAQS
attainment designation for the county. If the data are incomplete or
otherwise compromised, then an attainment determination will not be
possible.

Similarly, there are data quality requirements for hazardous air
pollutant (HAP) monitoring which is intended for use in exposure
assessment and health risk interpretation. It is not uncommon for an
agency to collect ambient HAP data only to discover later that the wrong
target compounds were reported or that detection limits were too high to
allow comparing the data against cancer risk benchmarks. These problems
can be minimized by effective planning which identifies the intended use
of monitoring data and delineates specific monitoring quality
objectives.

**8.2 Purpose**

The main goal of this section is to help Tribal staff achieve their
monitoring program objectives through an effective use of monitoring
data. We will give an overview of potential data uses and provide links
to relevant guidance documents and examples. Possible data uses include:
determining attainment of NAAQS for criteria pollutants; characterizing
population exposure to HAPs, also known as "air toxics"; assessing air
pollutant trends over time; and attributing source contribution to air
pollution.

Basic data summary and statistical techniques allow the monitoring
agency to effectively communicate project results. These methods are
important for a variety of purposes: to inform Tribal members and other
stakeholders about local air quality; to summarize monitoring results in
a final project report or grant related documents; and to describe prior
air quality findings as part of the justification for new or continued
funding in a grant application.

This section will be useful to an agency that has already collected a
dataset and needs help understanding it. However it may be even more
valuable to a program manager who is in the stages of planning an air
quality study as it will provide a clear understanding of what an
ambient monitoring program can do for them and what questions it can
answer. Depending on the technical capabilities of Tribal staff, some of
the techniques described here may be performed in-house while others may
require partnering with another agency or hiring a contractor.

**8.3 Recommendations for Specific Data Uses**

**8.3.1 Criteria pollutants**

Tribal agencies that conduct ambient air quality monitoring most
frequently collect data for the six common pollutants (also referred to
as \"criteria\" pollutants): carbon monoxide (CO), lead (Pb), nitrogen
dioxide (NO~2~), ozone (O~3~), particulate matter (PM), and sulfur
dioxide (SO~2~). PM falls into two categories: particles smaller than 10
microns in diameter (PM~10~) and particles smaller than 2.5 microns
(PM~2.5~). This section will describe how criteria pollutant monitoring
data may be interpreted and used as part of an air quality management
program.

For more information on sources of criteria pollutants, health and
environmental effects, efforts to help reduce emissions, and other
helpful resources, see:
[www.epa.gov/air/urbanair/6poll.html](http://www.epa.gov/air/urbanair/6poll.html)

8.3.1.1 NAAQS attainment

EPA has set NAAQS standards for the six criteria pollutants. The NAAQS
include both primary and secondary standards. Primary standards set
limits to protect public health, including the health of \"sensitive\"
populations such as asthmatics, children, and the elderly. Secondary
standards set limits to protect public welfare, including protection
against decreased visibility, damage to animals, crops, vegetation, and
buildings. The table below lists the current NAAQS for criteria
pollutants. Units of measure for the standards are parts per million
(ppm) by volume, milligrams per cubic meter of air (mg/m^3^), and
micrograms per cubic meter of air (µg/m^3^).

> **Table 1. National Ambient Air Quality Standards**

+--------------+----------------+------------------+-------------------+
| *            | **Primary      | **Averaging      | **Secondary       |
| *Pollutant** | Standards**    | Times**          | Standards**       |
+--------------+----------------+------------------+-------------------+
| Carbon       | 9 ppm (10      | 8-hour^1^        | None              |
| Monoxide     | mg/m^3^)       |                  |                   |
+--------------+----------------+------------------+-------------------+
|              | 35 ppm (40     | 1-hour^1^        | None              |
|              | mg/m^3^)       |                  |                   |
+--------------+----------------+------------------+-------------------+
| Lead         | 1.5 µg/m^3^    | Quarterly        | Same as Primary   |
|              |                | Average          |                   |
+--------------+----------------+------------------+-------------------+
| Nitrogen     | 0.053 ppm\     | Annual           | Same as Primary   |
| Dioxide      | (100 µg/m^3^)  |                  |                   |
|              |                | (Arithmetic      |                   |
|              |                | Mean)            |                   |
+--------------+----------------+------------------+-------------------+
| Particulate  | 50 µg/m^3^     | Annual^2^        | Same as Primary   |
| Matter       |                | (Arith. Mean)    |                   |
| (PM~10~)     |                |                  |                   |
+--------------+----------------+------------------+-------------------+
|              | 150 ug/m^3^    | 24-hour^1^       |                   |
+--------------+----------------+------------------+-------------------+
| Particulate  | 15.0 µg/m^3^   | Annual^3^        | Same as Primary   |
| Matter       |                | (Arith. Mean)    |                   |
| (PM~2.5~)    |                |                  |                   |
+--------------+----------------+------------------+-------------------+
|              | 65 ug/m^3^     | 24-hour^4^       |                   |
+--------------+----------------+------------------+-------------------+
| Ozone        | 0.08 ppm       | 8-hour^5^        | Same as Primary   |
+--------------+----------------+------------------+-------------------+
| Sulfur       | 0.03 ppm       | Annual (Arith.   | \-\-\-\-\-\--     |
| Oxides       |                | Mean)            |                   |
+--------------+----------------+------------------+-------------------+
|              | 0.14 ppm       | 24-hour^1^       | \-\-\-\-\-\--     |
+--------------+----------------+------------------+-------------------+
|              | \-\-\-\-\-\--  | 3-hour^1^        | 0.5 ppm (1,300    |
|              |                |                  | ug/m^3^)          |
+--------------+----------------+------------------+-------------------+

^1^ Not to be exceeded more than once per year.

^2^ To attain this standard, the 3-year average of the weighted annual
mean PM~10~ concentration at each monitor within an area must not exceed
50 ug/m^3^.

^3^ To attain this standard, the 3-year average of the weighted annual
mean PM~2.5~ concentrations from single or multiple community-oriented
monitors must not exceed 15.0 ug/m^3^.

^4^ To attain this standard, the 3-year average of the 98th percentile
of 24-hour concentrations at each population-oriented monitor within an
area must not exceed 65 ug/m^3^.

^5^ To attain this standard, the 3-year average of the fourth-highest
daily maximum 8-hour average ozone concentrations measured at each
monitor within an area over each year must not exceed 0.08 ppm.

"Designation" is the term EPA use to describe the air quality in a given
area for any of the criteria pollutants. Geographic areas are designated
as "attainment" or "nonattainment" based on ambient air monitoring data
collected in that area and reported to the Air Quality System (AQS)
national database. Tribes and States submit recommendations to the EPA
as to whether or not an area is attaining the NAAQS for a criteria
pollutant. After working with the Tribal or State agencies and
considering the air quality data, EPA officially designates an area as
attainment or nonattainment. If an area is designated as nonattainment
EPA informs the public that the air in the area is unhealthy to breathe,
and states, local and tribal governments must develop and implement
control plans to reduce pollution. A Tribal Implementation Plan (TIP) is
a set of regulatory programs that a tribe can develop and adopt to help
attain or maintain national air quality standards. Once a nonattainment
area meets the standards and additional redesignation requirements in
the CAA \[Section 107(d)(3)(E)\], EPA will designate the area to
attainment as a \"maintenance area.\"

The website listed below provides an unofficial list of Tribes in 8-hour
ozone nonattainment areas as of April 15, 2004. Official nonattainment
boundaries are specified in 40 CFR Part 81.
[www.epa.gov/ozonedesignations/tribaldesig.htm](http://www.epa.gov/ozonedesignations/tribaldesig.htm)

Detailed instructions on how to determine attainment status based on
ambient monitoring data may be found in the Code of Federal Regulations
(CFR) Title 40 Part 50. The relevant passages for each criteria
pollutant is included as Attachment 1 and may also be accessed on the
web at:

<http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=e18bc4907fc6d399c035b0bd125e238b&tpl=/ecfrbrowse/Title40/40cfr50_main_02.tpl>

8.3.1.2 Understanding the Air Quality Index (AQI) and AIRNow

##### 

The AQI is an index for reporting daily air quality. It tells how clean
or polluted the air is, and what associated health effects might be a
concern for the public. The AQI focuses on health effects that may be
experienced within a few hours or days after breathing polluted air. EPA
calculates the AQI for five of the criteria pollutants: O~3~, PM, CO,
SO~2~, and NO~x~. The AQI scale runs from 0 to 500. The higher the AQI
value, the greater the level of air pollution and the greater the health
concern. For example, an AQI value of 50 represents good air quality
with little potential to affect public health, while an AQI value over
300 represents hazardous air quality.

An AQI value of 100 generally corresponds to the national air quality
standard for the pollutant, which is the level EPA has set to protect
public health. AQI values below 100 are generally thought of as
satisfactory. When AQI values are above 100, air quality is considered
to be unhealthy -- at first for certain sensitive groups of people, then
for everyone as AQI values get higher.

Raw ambient air monitoring data is converted into AQI values using
standard formulas developed by EPA. An AQI value is calculated for each
pollutant in an area. The highest AQI value for the individual
pollutants is the AQI value for that day. For example, if a certain date
had AQI values of 90 for ozone and 88 for sulfur dioxide, the AQI value
would be 90 for the pollutant ozone on that day.

#####  

The purpose of the AQI is to help the public understand what local air
quality means to their health. To make it easier to understand, the AQI
is divided into six categories, each of which corresponds to a different
level of health concern. The six levels of health concern and what they
mean are:

-   **\"Good\"** The AQI value for your community is between 0 and 50.
    Air quality is considered satisfactory, and air pollution poses
    little or no risk.

-   **\"Moderate\"** The AQI for your community is between 51 and 100.
    Air quality is acceptable; however, for some pollutants there may be
    a moderate health concern for a very small number of people. For
    example, people who are unusually sensitive to ozone may experience
    respiratory symptoms.

-   **\"Unhealthy for Sensitive Groups\"** When AQI values are between
    101 and 150, members of sensitive groups may experience health
    effects. This means they are likely to be affected at lower levels
    than the general public. For example, people with lung disease are
    at greater risk from exposure to ozone, while people with either
    lung disease or heart disease are at greater risk from exposure to
    particle pollution. The general public is not likely to be affected
    when the AQI is in this range.

-   **\"Unhealthy\"** Everyone may begin to experience health effects
    when AQI values are between 151 and 200. Members of sensitive groups
    may experience more serious health effects.

-   **\"Very Unhealthy\"** AQI values between 201 and 300 trigger a
    health alert, meaning everyone may experience more serious health
    effects.

-   **\"Hazardous\"** AQI values over 300 trigger health warnings of
    emergency conditions. The entire population is more likely to be
    affected.

#### The AIRNow Web site delivers daily AQI forecasts as well as real-time AQI conditions for over 300 cities across the United States. The EPA developed the AIRNow program together with the National Oceanic and Atmospheric Administration (NOAA), National Park Service (NPS), Tribal, State, and Local agencies to provide the public with easy access to national air quality information. AQI data are presented in maps which were generated based on "real-time" ambient monitoring data using either federal reference or equivalent monitoring techniques or techniques approved by the state, local or tribal monitoring agencies. Although some preliminary data quality assessments are performed, the data as such are not fully verified and validated through the quality assurance procedures monitoring organizations use to officially submit and certify data in AQS. Therefore, data are used on the AIRNow Web site only for the purpose of reporting the AQI. Information on the AIRNow web site is not used to formulate or support regulation, guidance or any other Agency decision or position.

In 2005 there were 13 Tribal monitoring agencies that participated in
AIRNow. Tribes interested in joining the AIRNow network should contact
the appropriate OAQPS staffer, who is currently Richard Wayland.

 

Air quality forecasts and more information about AQI and AIRNow is
available at: [www.airnow.gov](http://www.airnow.gov/)

> **8.3.2 Air quality characterization for ambient, deposition, and
> visibility data**

The previous section was focused specifically on criteria pollutants and
interpreting data in terms of the NAAQS rules. Beyond the six criteria
pollutants, however, there are hundreds of other pollutants and indices
that a monitoring agency may wish to address. These non-criteria
pollutants and measures include ambient air toxics, wet/dry deposition,
visibility data, and even biomonitoring of ozone injury to sensitive
plants. These types of data do not have corresponding national air
quality standards that help to guide data summary and interpretation.
Instead, monitoring results should be described using basic summary
statistics. The data may also be visualized using simple graphic
techniques.

**8.3.2.1 Basic summary statistics**

The first step in summarizing air quality data is to take inventory of
the number of samples collected, the range of measurements, and to
provide related information about the monitoring schedule. It is
important to specify the measurement units of the pollutant. If any of
the samples are below detection limits (called "nondetects") then it
becomes necessary to state the method detection limit (MDL) as well as
the number or percent of samples below the MDL. An example in table form
is shown below.

> **Table 2. Example of monitoring data summary**

  --------------- ------------ ------------ ----------- ---------- --------- --------- --------- -----------
  **Pollutant**   **Sampling   **Sampling   **Total     **Unit**   **MDL**   **Min.    **Max.    **Percent
                  schedule**   period**     samples**                        value**   value**   samples
                                                                                                 \<MDL**

  Benzene         1-in-6 days  Jan. 2003 -- 107         ppbC       0.01      0.02      1.3       0
                               Dec. 2004                                                         

  1,3-butadiene   1-in-6 days  Jan. 2003 -- 107         ppbC       0.01      Below MDL 0.8       78%
                               Dec. 2004                                                         

  Arsenic         Monthly      Jan. 2003 -- 18          ug/m^3^    0.002     Below MDL 0.012     65%
  (PM~10~)                     June. 2004                                                        

  Cadmium         Monthly      Jan. 2003 -- 18          ug/m^3^    0.01      Below MDL 0.02      21%
  (PM~10~)                     June. 2004                                                        

  Lead (PM~10~)   Monthly      Jan. 2003 -- 18          ug/m^3^    0.005     0.008     0.31      0
                               June. 2004                                                        
  --------------- ------------ ------------ ----------- ---------- --------- --------- --------- -----------

If any of the monitored pollutants has nondetect values then this issue
must be resolved before moving on to data analysis. EPA recommends that
nondetects be replaced with a value equal to half of the detection limit
for a given pollutant (1/2 MDL). In the example above, the detection
limit for 1,3-butadiene is 0.01 ppbC, thus nondetects should be replaced
with 0.005 ppbC throughout the dataset. These substituted values are
then used alongside "real" values in calculating summary statistics. We
do not advise deleting nondetects from the dataset because this will
cause an upward bias in the results; similarly nondetects should not be
replaced by zeroes because this biases the results downward.

Note that a high percentage of nondetects results in less reliable data
summary statistics. Although there is no definite cut-off, a pollutant
with greater than 50% nondetects should be treated with care and one
with more than 80% nondetects may be removed from further analysis.
Depending on the importance of a specific pollutant to the monitoring
study, the data analyst has a few choices: state that the pollutant has
a very high rate of nondetects and remove it from the data analysis;
include the pollutant and point out potential problems related to
nondetects; include the pollutant and use advanced statistical
techniques developed for datasets with a high rate of nondetects.

Statistical techniques that may be useful in handling datasets with a
high rate of nondetects are described in the following article:

Less than obvious -- statistical treatment of data below the detection
limit, Dennis R. Helsel (USGS), Environmental Science and Technology,
Vol. 24, No. 12, 1990.

The rest of this section will describe ways to summarize basic
characteristics of the dataset using common statistical measures. Some
useful examples include: measures of central tendency, such as the mean
or median; measures of relative standing, such as percentiles; measures
of dispersion, such as range, variance, standard deviation, coefficient
of variation, or interquartile range; measures of distribution symmetry
or shape; and measures of association between two or more variables,
such as correlation. These measures can then be used for description and
communication about the dataset.

The definitions and procedures outlined in parts 3.2.1 and 3.2.2. are
primarily taken from the EPA document "Guidance for Data Quality
Assessment -- Practical Methods for Data Analysis"

> (EPA/600/R-96/084) which is available in full at this website:

[www.epa.gov/quality/qs-docs/g9-final.pdf](http://www.epa.gov/quality/qs-docs/g9-final.pdf)

This section provides mathematical formulas that allow the user to
calculate descriptive statistics using a simple calculator or computer
spreadsheet program. Data analysts that are interested in continuing on
to do advanced statistical procedures may consider investing in a
statistical software package and attending training sessions to practice
using them. The end of this section provides resources for those
interested in learning more.

[Central tendency]{.underline}

The most common estimates for central tendency in environmental data are
the mean and median. The **mean** may be considered to be the "center of
gravity" of the dataset. It is calculated as a basic arithmetic average.
The **median** is the value which falls directly in the middle of the
data when the measurements are ranked in order from smallest to largest.
Thus ½ of the data are smaller than the sample median and ½ of the data
are larger than the sample median. Unlike the mean, the median is not
influenced by a small number of extreme values.

> **Formula 1. Measuring central tendency**

![](media/image1.wmf){width="5.374305555555556in"
height="2.5229166666666667in"}

[Relative Standing (Percentiles)]{.underline}

It may be useful to know the relative position of one or several
observations in relation to all of the observations. Percentiles are one
such measure of relative standing that may also be useful for
summarizing data. A percentile is the data value that is greater than or
equal to a given percentage of the data values. For example the data
point which is the 25^th^ percentile is greater than or equal to 25% of
the data values and is less than or equal to 75%. Important percentiles
usually reviewed are the quartiles of the data: the 25^th^, 50th, and
75^th^ percentiles. The 50^th^ percentile is also called the sample
median (previously described), and the 25^th^ and 75^th^ percentiles are
used to estimate the dispersion of a data set (next section).

> **Formula 2. Calculating percentiles**

![](media/image2.wmf){width="5.252777777777778in"
height="2.102777777777778in"}

[Measures of Dispersion]{.underline}

Measures of central tendency are more meaningful if accompanied by
information on how the data spread out from the center. Measures of
dispersion in a data set include the range, variance, sample standard
deviation, coefficient of variation, and the interquartile range. These
measures are all described below and formulas provided.

The easiest measure of dispersion to compute is the sample ***range***.
For small samples, the range is easy to interpret and may adequately
represent the dispersion of the data. For large samples, the range is
not very informative because it only considers (and therefore is greatly
influenced) by extreme values.

The sample ***variance*** measures the dispersion from the mean of a
data set. A large sample variance implies that there is a large spread
among the data so that the data are not clustered around the mean. A
small sample variance implies that there is little spread among the data
so that most of the data are near the mean. The sample variance is
affected by extreme values and by a large number of nondetects. The
sample standard deviation is the square root of the sample variance and
has the same unit of measure as the data.

The ***coefficient of variation (CV)*** is a unitless measure that
allows the comparison of dispersion across several sets of data. The CV
is often used in environmental applications because variability
(expressed as a standard deviation) is often proportional to the mean.

When extreme values are present, the ***interquartile range*** may be
more representative of the dispersion of the data than the standard
deviation. This statistical quantity does not depend on extreme values
and is therefore useful when the data include a large number of
nondetects.

> **Formula 3. Calculating measures of dispersion**

![](media/image3.wmf){width="5.372916666666667in"
height="3.0833333333333335in"}

8.3.2.2 Trends analysis

EPA uses trend analysis to assess year-to-year changes in ambient air
quality and pollutant emissions. Annual Trends Reports are EPA\'s
\"report card\" on the status of air quality and emission reductions.
Annual trends reports and special studies dating back to 1994 are
available at:
[www.epa.gov/airtrends/reports.html](http://www.epa.gov/airtrends/reports.html).
Some methods used in these reports will be useful to Tribal agencies.

The data analyst needs a reasonably long and complete dataset to be able
to distinguish a genuine trend from other kinds of data variability. A
suspected trend in data may not be a "real" trend, but a function of
data variation caused by weather conditions or other factors. For
example, because higher temperatures cause more formation of some
pollutants, like ozone and formaldehyde, a year with warmer temperatures
may have higher concentrations of these pollutants, regardless of any
possible changes in precursor emissions. Thus the measurements in one
year may be higher than the previous year, but we cannot reliably say
that there is an upward trend in ambient concentrations.

Although it is tempting to calculate trends based on two or three years
of data, more years are needed to calculate a meaningful trend. For
dispersion modeling, meteorologists recommend using between 3 and 5
years of data just to assess the "baseline" condition. With this in
mind, we suggest the following:

-   1 to 3 years of monitoring data -- do not use for trend analysis

-   4 to 5 years of monitoring data -- consider trend results to be
    "preliminary"

-   6 or more years of monitoring data -- adequate dataset for trend
    analysis

If there are enough years of data available, then it is also important
to confirm that each year has adequate data completeness. Multi-year
trends can only be calculated if each year has a valid summary statistic
(e.g. annual mean) based on sufficient data. The issue of data
completeness was previously discussed in the section on data quality
objectives and data validation.

Assuming that there are enough complete years of monitoring, then an
annual air quality statistic can be determined for each individual year
of air monitoring and then a trend may be evaluated for multiple years.
The trend statistic can be one of those described in Section 3.2.1 (such
as the annual average or 90^th^ percentile) or a NAAQS design value as
described in Section 3.1.1 (such as the PM~2.5~ 24-hour maximum). This
section will explain how to quantify and visualize trends in monitoring
data.

[Percent change]{.underline}

Actual ambient concentrations have little meaning to the general public
and a change in concentration (for example a "0.04 ppb decline over 8
years") is even more abstract. For this reason EPA most often explains
trends in terms of a percent change over time. The example below shows
the trend calculation and graph format most widely used in trend
reports. The main trend statistic is the combined annual average of
multiple monitoring sites. The figure also shows the 90^th^ and 10^th^
percentiles of all site averages for each year.

**Figure 1. CO air quality, 1983-2002, based on annual second maximum
8-hr average**![](media/image4.png){width="3.8756944444444446in"
height="2.6354166666666665in"}

**Formula 4. Percent change over multiple years of monitoring**

$$P = \begin{array}{r}
\left\lbrack \underline{\left( C_{F} - C_{S} \right)} \middle| \right\rbrack \\

\end{array}$$

Where C~S~ = concentration at the start; C~F~ = concentration at the
finish of the time period. A positive P indicates an upward trend and a
negative value indicates a downward trend.

In the carbon monoxide example above,

$$P = \begin{array}{r}
\left( \underline{2\text{.}9\text{ppm} - 8\text{.}2\text{ppm}} \middle| \right) \\

\end{array}$$

There are some important pitfalls to the percent change approach to
trends. The main concern is that if the dataset has strong year-to-year
variability, then the existence of a positive or negative trend is
dependent on which years are chosen as the start and finish. The figure
below shows national annual total manganese emissions as reported to the
Toxics Release Inventory (TRI). The percent change in emissions between
1988 and 2003 is --26%. However, the downward trend is magnified if we
look only at 1989 through 1997 (--88%); the trend is relatively flat if
the time period is 1993--1999 (--2%); the trend reversed if we look at
1991 to 1999 (+19%). For this reason it is preferable to use the percent
change method for a dataset with smooth trends. Highly variable datasets
should be evaluated by using a moving average (described below) or with
a more rigorous statistical method, such as linear regression or using
non-parametric methods.

**Figure 2. Example of dataset with variable year-to-year data**

![](media/image5.wmf){width="3.9993055555555554in"
height="2.6069444444444443in"}

[National Air Toxics Trend Site (NATTS) method]{.underline}

Trends within the new NATTS network are figured based on six (6) years
of annual average concentrations for key HAPs, specifically benzene,
1,3-butadiene, arsenic, chromium, acrolein, and formaldehyde. The trend
is calculated by finding the percent difference between the mean of the
first three annual concentrations and the mean of the last three annual
concentrations. This is a variation on the percent change method
described above.

**Formula 5. NATTS trend method**

First the annual average concentration (Xi) is found for each year i =
1, 2, 3, 4, 5 & 6. Then the mean (X) for the first three years and the
mean (Y) for years 4 through 6 is calculated:

![](media/image6.wmf){width="2.8756944444444446in"
height="0.46944444444444444in"}

The downward trend (T) is the percent decrease from the first 3-year
period to the second.

![](media/image7.wmf){width="1.125in" height="0.4875in"}

According to the DQOs for the NATTS program, a trend of at least 15% is
considered a significant decrease. A tribal agency may wish to adopt
this protocol for their own monitoring program or adapt it as needed
through consultation with quality assurance experts. The Quality
Assurance Guidance Document for the NATTS program

is available at:

[www.epa.gov/ttn/amtic/files/ambient/airtox/nattsqapp.pdf](http://www.epa.gov/ttn/amtic/files/ambient/airtox/nattsqapp.pdf)

[Moving average]{.underline}

A dataset with considerable year-to-year variability may be smoothed out
by calculating a moving average. Instead at looking at annual averages
that rise and fall with each year, we look at 3-year, 4-year, or 5-year
averages which are less subject to variability swings.

The example below shows data graphed first as annual averages and then
as a moving 3-year average. The first figure shows annual averages from
1997 to 2005; the second shows the combined average for 1997 through
1999, then 1998-2000, 1999-2001, and so forth. The downward trend in
data is more evident in the second figure.

> [Year]{.underline} [Mercury wet deposition (µg/m^2^)]{.underline}
>
> 1997 12.8
>
> 1998 13.7
>
> 1999 11.9
>
> 2000 12.0
>
> 2001 13.1
>
> 2002 10.8
>
> 2003 11.7
>
> 2004 11.1
>
> 2005 9.6

**Figure 3. Data trend presented with annual average and moving
average** ![](media/image8.wmf){width="3.9479166666666665in"
height="2.0416666666666665in"}

![](media/image9.wmf){width="3.9479166666666665in" height="2.125in"}

8.3.2.3 Data visualization

Simple graphing techniques are useful to describe the dataset and
communicate monitoring results. Graphs can be used to identify patterns
and trends in the data. Graphical representations include displays of
individual data points, statistical quantities, temporal data, spatial
data, and two or more variables.

Detailed instructions on how to produce these graphics are provided in
Section 2 of the previously mentioned "Guidance for Data Quality
Assessment -- Practical Methods for Data Analysis", available at:
[www.epa.gov/quality/qs-docs/g9-final.pdf](http://www.epa.gov/quality/qs-docs/g9-final.pdf)

[Histogram/Frequency Plots]{.underline}

Two of the oldest methods for summarizing data distributions are the
frequency plot and the histogram. Both the histogram and the frequency
plot use the same basic principles to display the data: dividing the
data range into units, counting the number of points within the units,
and displaying the data as the height or area within a bar graph.

**Figure 5. Example of a frequency plot**

![](media/image10.wmf){width="2.498611111111111in"
height="1.7798611111111111in"}

[Box and Whisker Plot]{.underline}

A box and whisker plot or box plot is a schematic diagram useful for
visualizing important statistical quantities of the data. A box and
whiskers plot is composed of a central box divided by a line and two
lines extending out from the box called whiskers. The length of the
central box indicates the spread of the bulk of the data (the
inter-quartile range, 25^th^ to 75^th^ percentile) while the length of
the whiskers show how stretched the tails of the distribution are. The
sample median is displayed as a line through the box and the sample mean
is displayed using a '+' sign. Any unusually small or large data points
are displayed by a '\*' on the plot.

**Figure 6. Example of a box and whisker plot**

![](media/image11.wmf){width="0.7951388888888888in"
height="1.511111111111111in"}

[Scatter Plot]{.underline}

For data sets consisting of paired observations where two or more
variables are measured for each sampling point, a scatter plot is one of
the most powerful tools for analyzing the relationship between two or
more variables. A scatter plot clearly shows the relationship between
two variables. Both potential outliers from a single variable and
potential outliers from the paired variables may be identified on this
plot. A scatter plot also displays the correlation between the two
variables. Scatter plots of highly linearly correlated variables cluster
compactly around a straight line.

> **Figure 7. Example of a scatter plot**

![](media/image12.wmf){width="3.376388888888889in"
height="2.196527777777778in"}

[Time Plot]{.underline}

One of the simplest plots to generate that provides a large amount of
information is a time plot. A time plot is a plot of the data over time.
This plot makes it easy to identify large-scale and small-scale trends
over time. Small-scale trends show up on a time plot as fluctuations in
smaller time periods. For example, ozone levels over the course of one
day typically rise until the afternoon, then decrease, and this process
is repeated every day. An example of a large-scale trend is a multi-year
decrease in air pollution resulting from effective air quality control
programs. For example, the annual average concentration of NO~x~ at a
particular monitoring site may decline over the course of several years
as a result of emissions controls at local industries and the
introduction of cleaner cars.

> **Figure 8. Example of a time plot**

![](media/image13.wmf){width="4.248611111111111in"
height="2.134027777777778in"}

8.3.2.4 References, tools, and resources

## [EPA courses]{.underline}

## 

EPA\'s Air Pollution Training Institute (APTI) primarily provides
technical air pollution training to state, tribal, and local air
pollution professionals, although others may benefit from this training.
The curriculum is available in classroom, telecourse, self-instruction,
and web-based formats. A few potentially useful courses are described
below.

## 

Introduction to Environmental Statistics

This series of online lectures was developed for USEPA by the University
of Illinois at Chicago School of Public Health, Environmental and
Occupational Health Sciences Division. No registration is required to
access the archived lectures. The lectures are available at this
website:

[www.epa.gov/air/oaqps/eog/envirostats/index.html](http://www.epa.gov/air/oaqps/eog/envirostats/index.html)

-   Module 1: Interpreting Your Monitoring Data

-   Module 2: Sampling and Analytical Limitations & Sample Detection
    Limits

-   Module 3: Quality Assurance Quality Control

```{=html}
<!-- -->
```
-   Module 4: Analysis of Trends

-   Module 5: Language of Data Graphing

-   Module 6: Censored Values and Extreme Values

-   Module 7: Fundamentals of Trajectory Analysis

## 

## Introduction to Environmental Statistics - SI:473B

This course introduces the student to the basic concepts of statistical
analysis. The course was designed for students with little formal
education in statistics who must apply statistical techniques to analyze
environmental data. The package has seven modules, a workbook, and a VHS
format video tape. The workbook and video tape are mailed to the student
by EPA, but it is necessary to acquire one of the recommended companion
texts.

## Course information is available at: [**www.epa.gov/air/oaqps/eog/catalog/si473b.html**](http://www.epa.gov/air/oaqps/eog/catalog/si473b.html)

# Training Courses on Quality Assurance and Quality Control Activities

EPA Quality Staff develops a variety of traditional training courses on
quality assurance (QA) and quality control (QC) activities and the EPA
quality system. Two subject area of particular interest are
"Interpreting monitoring data" and "Introduction to Data Quality
Assessment". Materials are available at:
[www.epa.gov/quality/trcourse.html](http://www.epa.gov/quality/trcourse.html)

[Other tools and resources]{.underline}

Statistics books:

-   Basic Statistical Methods for Engineers and Scientists

Adam Neville, John Kennedy, International Textbook Company (out of
print)

-   Probability and Statistics for Engineers, Irwin Miller, John Freund,
    Prentice Hall

-   Statistics Concepts and Applications, David Anderson, Dennis J.
    Sweeney, Thomas A. Williams, West

-   Exploring Statistics -- A Modern Introduction, Larry J. Kitchens,
    West

-   Engineering Statistics, Robert V. Hogg, Johannes Ledolter, Macmillan

-   Introduction to Statistical Thinking, E.A. Maxwell, Prentice Hall

-   Statistical Analysis for Decision Making, Morris Hamburg, Harcourt
    Brace Jovanovich

EPA has a website for Quality-Related Resources which contains links to
other sources of information on quality systems available on the web:

[www.epa.gov/quality/qa_links.html](http://www.epa.gov/quality/qa_links.html)

Examples of tools and resources available through the EPA quality
resources page:

-   DataPlot (National Institutes of Science and Technology) is a free,
    public-domain, multi-platform software system for scientific
    visualization, statistical analysis, and non-linear modeling.
    [www.itl.nist.gov/div898/software/dataplot.html/](http://www.itl.nist.gov/div898/software/dataplot.html/)

-   StatPages.Net (by John C. Pezzullo) contains links to online
    calculators, free statistical software, online statistics books,
    tutorials, and related resources.\
    [members.aol.com/johnp71/javastat.html](http://members.aol.com/johnp71/javastat.html)

-   Statistics Calculators (UCLA Department of Statistics) includes
    calculators for statistical graphs, power calculations, sample size
    calculations, etc.
    [calculators.stat.ucla.edu/](http://calculators.stat.ucla.edu/)

-   Guide to Statistical Software (George Mason University) provides a
    comparison of commercially available statistical software.
    [www.galaxy.gmu.edu/papers/astr1.html](http://www.galaxy.gmu.edu/papers/astr1.html)

**8.3.3 Putting monitoring data into context**

[Criteria pollutants]{.underline}

In addition to determining NAAQS attainment and AQI values, Tribal
monitoring agencies may benefit from putting their monitoring data into
a broader context. There are a few ways to do this. The Tribe may look
up data for the same pollutant at other monitoring sites located in the
same State or region to see how the values compare. It may also be
helpful to look at a nation-wide summary of data or a list of
nonattainment areas. A broader context may also be obtained by learning
about national trends in air quality data.

EPA's AirData website provides access to air pollution data for the
entire US as submitted to AQS. AirData produces reports and maps of air
pollution data based on user-specified queries. For example a Tribal
agency located in Arizona may wish to look up last year's ozone data for
all monitoring sites in the State. The link below is the interface where
the user selects the geographic area for the data search. Subsequent web
pages narrow the search to the desired pollutant, year, and report
format.
[www.epa.gov/air/data/geosel.html](http://www.epa.gov/air/data/geosel.html)

EPA's Air Explorer is a collection of user-friendly visualization tools
for air quality analysts. The tools generate maps, graphs, and data
tables based on criteria pollutant data reported to AQS. This is a
developmental site. Based on user feedback, EPA is continually improving
the existing tools and developing new
ones.[www.epa.gov/mxplorer/index.htm](http://www.epa.gov/mxplorer/index.htm)

EPA's "Green Book" lists all nonattainment areas in the US. The user can
access a variety of maps and reports for each criteria pollutant at this
web site:
[www.epa.gov/air/oaqps/greenbk/](http://www.epa.gov/air/oaqps/greenbk/)

EPA tracks air pollution trends using two main indicators: ambient air
monitoring data and pollutant emissions. EPA estimates nationwide
emissions of criteria pollutants and air toxics based on many factors,
including actual measurements, levels of industrial activity, fuel
consumption, vehicles miles traveled, and other estimates of activities
that cause pollution. For EPA\'s most recent evaluation of air pollution
trends, see: [www.epa.gov/airtrends/](http://www.epa.gov/airtrends/)

The Visibility Information Exchange Web System (VIEWS) is an online
exchange of air quality data, research, and ideas designed to understand
the effects of air pollution on visibility in support of the Regional
Haze Rule. <http://vista.cira.colostate.edu/views>

[Air toxics, deposition, and other monitoring data]{.underline}

Air toxics monitoring data from other sites in the U.S., as submitted to
AQS, may be accessed through the AirData website. Additionally, some
materials are available from nation-wide air toxics data analyses. The
following links may be useful for putting toxics data into context:

-   Geographic Variability in Air Toxics

[www.epa.gov/ttn/amtic/files/ambient/airtox/2005%20workshop/spatial.pdf](http://www.epa.gov/ttn/amtic/files/ambient/airtox/2005 workshop/spatial.pdf)

-   Temporal Trends in Air Toxics
    [www.epa.gov/ttn/amtic/files/ambient/airtox/2005%20workshop/temporal.pdf](http://www.epa.gov/ttn/amtic/files/ambient/airtox/2005 workshop/temporal.pdf)

The Clean Air Status and Trends Network (CASTNET) is the nation\'s
primary source for data on dry acidic deposition and rural, ground-level
ozone. CASTNET consists of over 80 sites across the eastern and western
United States and is cooperatively operated and funded with the National
Park Service. Data are available for download for ambient air pollutants
and wet/dry deposition at this site:
[www.epa.gov/castnet/data.html](http://www.epa.gov/castnet/data.html)

The National Atmospheric Deposition Program/National Trends Network
(NADP/NTN) is a nationwide network of precipitation monitoring sites.
The network includes over 200 monitoring sites, including those operated
by 9 Tribal agencies. Data are available for download at:
<http://nadp.sws.uiuc.edu/sites/ntnmap.asp>

The Mercury Deposition Network (MDN) is intended to develop a national
database of weekly concentrations of total mercury in precipitation and
the seasonal and annual flux of total mercury in wet deposition.
<http://nadp.sws.uiuc.edu/sites/mdnmap.asp>

EPA established the National Dioxin Air Monitoring Network (NDAMN) to is
determine the temporal and geographical variability of atmospheric CDDs,
CDFs and coplanar PCBs at rural and nonimpacted locations throughout the
United States. Summary reports are available:

[www.epa.gov/glnpo/monitoring/air2/bio_toxics.html](http://www.epa.gov/glnpo/monitoring/air2/bio_toxics.html)

The Integrated Atmospheric Deposition Network (IADN) was established by
the United States and Canada for conducting air and precipitation
monitoring in the Great Lakes Basin. PAHs, PCBs, and organochlorine
compounds are measured in air and precipitation samples in the U.S. and
Canada. See:
[www.msc.ec.gc.ca/iadn/index_e.html](http://www.msc.ec.gc.ca/iadn/index_e.html)

The USDA Forest Service, Forest Health Monitoring (FHM) is a national
program designed to determine the status, changes, and trends in
indicators of forest condition on an annual basis. The FHM program uses
data from ground plots and surveys, aerial surveys, and other biotic and
abiotic data sources and develops analytical approaches to address
forest health issues that affect the sustainability of forest
ecosystems. See: <http://fhm.fs.fed.us/>

The USDA - Forest Service\'s Forest Inventory and Analysis (FIA) uses
biomonitoring to monitor the potential impact of tropospheric ozone
(smog) on forests. This program involves using bioindicator plants to
detect and quantify ozone stress in the forest environment. A nationwide
network of ozone biomonitoring sites has been established across the
forested landscape. Each year these sites are evaluated for the amount
and severity of ozone injury on sensitive plants. The foliar injury data
is used to monitor changes in relative air quality over time and to
examine relationships between ozone stress and tree health. See:
[www.fiaozone.net/](http://www.fiaozone.net/)

**8.3.4 Source apportionment**

In the absence of air monitoring, pollutant emissions data may be used
to help characterize air quality. This approach is discussed in more
detail elsewhere in this document. In this Section we focus on
evaluating air monitoring data in the context of emissions sources that
may be impacting the monitor site. Different approaches are described to
identify pollution sources and to estimate their potential to affect
local air quality.

8.3.4.1 Using emissions inventories

If monitoring data show that a specific pollutant is exceeding air
quality standards, or is otherwise causing concern, then emission
inventories can identify potential sources. Summary emission data are
most easily accessed on EPA's website:
[www.epa.gov/air/data](http://www.epa.gov/air/data). By searching in the
state or county of interest in AirData, the user can access the National
Emission Inventory (NEI) for data on point, nonpoint, and mobile
sources. NEI contains information about sources that emit criteria air
pollutants and their precursors, and hazardous air pollutants. The
AirData website generates reports based on facility-specific and county
aggregate emissions data.

Tribal agencies may want to find more detailed information or identify
smaller sources that might not be included in the NEI. They can contact
their respective state environmental agency to get more detailed
emissions data.

8.3.4.2 Wind direction analysis

Meteorological data collected at an air monitoring site can be used to
further interpret pollutant measurements and potential impact from
emissions sources. Wind data can be summarized over a year or multiple
years to show prevailing wind direction at a given site. A diagram
called a "wind rose" characterizes the wind conditions over time. The
example below is a wind rose produced by the Texas Commission on
Environmental Quality for Wichita Falls. The figure shows the frequency
of winds coming from each direction, broken out by wind speed category.

**Figure 9. Wichita Falls, Texas wind rose**

![](media/image14.png){width="3.0in" height="2.25in"}

If a major pollution source is identified near Tribal land, then a wind
rose can show whether the air monitor site is likely to be downwind of
the emission source on an occasional or frequent basis. An industrial
facility that is predominantly upwind of Tribal land is more likely to
impact the air monitor than a facility that is generally downwind. A
wind rose program called WRPLOT View is available from Lakes
Environmental Software for free download at this site:
[www.weblakes.com/lakewrpl.html](http://www.weblakes.com/lakewrpl.html)

To investigate further, the data analyst may conduct a wind-direction
analysis. This approach requires finding daily wind data that is
reported concurrently with air sampling events. Monitoring data may be
divided into "high pollution days" and "low pollution days", and the
meteorological data consulted to see whether higher concentrations occur
on days when the winds come from a certain direction. Alternatively,
each hourly or daily pollutant measurement can be divided into one of 16
categories according to the predominant wind sector (north,
north-northeast, northeast, east-northeast, etc.) and the average
concentrations for all sectors compared with one another.

Tribal agencies may generate wind roses or conduct wind-direction data
analysis using their own on-site meteorological data. If the Tribe does
not have a met station, data may potentially be obtained from other
agencies that have a nearby meteorological station, for example another
environmental or meteorological agency. In some cases, the data may be
downloaded from AQS. Technical staff at the state agency may have some
insights about how to locate data from other sources. Historic wind data
for many communities (useful for wind roses) is available for free
download at this website: [www.webmet.com](http://www.webmet.com/).
Recent meteorological data is considerably more difficult to find and
often must be purchased from a private company.

If long-range transport of pollutants is a concern then another approach
to consider is the HYSPLIT (HYbrid Single-Particle Lagrangian Integrated
Trajectory) model developed by NOAA. Hysplit can be used to map a back
trajectory which shows where an air parcel passed before reaching the
air monitor. The example below shows the back trajectory of different
air parcels that may have reached a monitor in western Michigan over a
24-hour period. The air parcels originated in several different states
(Iowa, Missouri, Illinois and Indiana) however they all passed through
northern Illinois before reaching the monitor in Michigan. If this
particular date had been a high ozone day, then the Hysplit results
would suggest that precursor pollutants from the greater Chicago area
contributed to ozone formation. Hysplit can be downloaded for free or
used on-line on the NOAA website:
[www.arl.noaa.gov/ready/hysplit4.html](http://www.arl.noaa.gov/ready/hysplit4.html)

**Figure 10. Example of Hysplit backward wind trajectory**

![](media/image15.png){width="3.375in" height="2.5097222222222224in"}

8.3.4.3 Receptor modeling

Receptor models are mathematical or statistical procedures for
identifying and quantifying the sources of air pollutants at a receptor
(air monitor) location. Unlike dispersion models, receptor models do not
use pollutant emissions, meteorological data and chemical transformation
mechanisms to estimate the contribution of sources to receptor
concentrations. Instead, receptor models use the chemical and physical
characteristics of gases and particles measured at source and receptor
to both identify the presence of and to quantify source contributions to
receptor concentrations. These models are used as part of State
Implementation Plans (SIPs) for identifying sources contributing to air
quality problems. The EPA has developed the Chemical Mass Balance (CMB)
and UNMIX models as well as the Positive Matrix Factorization (PMF)
method for use in air quality management. CMB fully apportions receptor
concentrations to chemically distinct source-types depending upon the
source profile database, while UNMIX and PMF internally generate source
profiles from the ambient data.

Receptor models have been used most often to identify the sources of
PM~2.5~ and ozone. PM~2.5~ modeling requires a speciated dataset
(carbon, ions, and trace elements) whereas ozone precursor modeling
calls for speciated VOC data. Receptor models require some training and
experience to operate effectively. Monitoring agencies may prefer to
hire a contractor or partner with another agency or university to get
this work done. EPA approved models and supporting materials are
available at:
[www.epa.gov/scram001/receptorindex.htm](http://www.epa.gov/scram001/receptorindex.htm)

**8.3.5 Exposure assessment for hazardous air pollutants**

Air toxics, or HAPs, are those pollutants that are known or suspected to
cause cancer or other serious health effects, such as reproductive
effects or birth defects, or adverse environmental effects. Examples of
toxic air pollutants include benzene, which is found in gasoline;
perchlorethlyene, which is emitted from some dry cleaning facilities;
and methylene chloride, which is used as a solvent and paint stripper by
a number of industries. Other listed air toxics include dioxin,
asbestos, toluene, and metals such as cadmium, mercury, chromium, and
lead compounds.

Links to more information about air toxics are provided below.

-   EPA's Health Effects Notebook provides fact sheets about the 188
    HAPs:
    [www.epa.gov/ttn/atw/hlthef/hapindex.html](http://www.epa.gov/ttn/atw/hlthef/hapindex.html)

-   Air Pollution and Health Risk

> [www.epa.gov/ttn/atw/3_90_022.html](http://www.epa.gov/ttn/atw/3_90_022.html)

-   Evaluating Exposures to Toxic Air Pollutants: A Citizen\'s Guide

> [www.epa.gov/ttn/atw/3_90_023.html](http://www.epa.gov/ttn/atw/3_90_023.html)

-   Risk Assessment for Toxic Air Pollutants: A Citizen\'s Guide

> [www.epa.gov/ttn/atw/3_90_024.html](http://www.epa.gov/ttn/atw/3_90_024.html)

Risk assessment is a tool used by environmental specialists to estimate
the increased risk of health problems in people who are exposed to
different amounts of toxic substances over a long period of time. The
risk assessment process has four steps, which are described below.

-   Hazard assessment -- what health problems are caused by the
    pollutant?

-   Dose-response assessment -- what are the health problems at
    different exposures?

-   Exposure assessment -- how much of the pollutant do exposed people
    inhale?

-   Risk characterization -- what is the extra risk of health problems
    in the exposed population?

Air toxics monitoring data may be used in the exposure assessment step
of risk assessment. If sufficient data exist for the pollutants of
concern, then monitoring data may be used instead of, or in addition to,
dispersion modeling outputs.

Using monitoring data in a risk assessment can be a very complex
process, requiring assistance from a statistician and toxicologist,
among other specialists. To decide whether a full-blown risk assessment
is warranted, EPA Region 4 scientists developed a screening procedure
that can help monitoring staff do a preliminary evaluation of their air
toxics data. The document is available at this website:

A Preliminary Risk-Based Screening Approach for Air Toxics Monitoring
Data Sets

[www.epa.gov/region4/air/airtoxic/athera1.htm](http://www.epa.gov/region4/air/airtoxic/athera1.htm)

EPA has also developed a Community Air Screening How-to Manual for use
by groups that includes non-technical community residents and leaders as
well as technical experts. The Manual describes a process that uses
input from a wide variety of community stakeholders.

[www.epa.gov/oppt/cahp/howto.html](http://www.epa.gov/oppt/cahp/howto.html)

If the Tribal agency has determined that a complete technical risk
assessment is needed, then EPA guidance documents are available for use
by Tribal staff or contractors. The Air Toxics Risk Assessment Reference
Library is located at:
[www.epa.gov/ttn/fera/risk_atra_main.html](http://www.epa.gov/ttn/fera/risk_atra_main.html).
The library provides information on the fundamental principles of
risk-based assessment for air toxics and how to apply those principles
in different settings as well as strategies for reducing risk at the
local level.

EPA has compiled dose-response data for air toxics for use in risk
assessments, including values for long-term (chronic) inhalation
short-term (acute) inhalation exposures. This information is regularly
updated as new information becomes available about the toxicity of
specific HAPs. The dose-response values provided at this site are
recommended by EPA as the most appropriate for use in air toxics risk
assessment.
[www.epa.gov/ttn/atw/toxsource/summary.html](http://www.epa.gov/ttn/atw/toxsource/summary.html)

> **8.3.6 Multi-media risk assessment using ambient and deposition
> monitoring data**

For a limited subset of HAPs, it is important to consider deposition
from air to soil, vegetation, or water bodies. Many studies indicate
that some pollutants emitted into the atmosphere (e.g., mercury) are
passed to humans or wildlife through non-inhalation pathways. An example
would be an air pollutant depositing from the air onto the soil,
followed by ingestion of the soil by people or by other living things in
an ecosystem. These air pollutants typically are persistent in the
environment, have a strong tendency to bioaccumulate, and exhibit
moderate to high toxicity.

A variety of computer models are available to describe the multimedia
transport and fate of pollutants released to the atmosphere. EPA
developed TRIM.FaTE, a model that can estimate pollutant concentrations
in multiple environmental media and biota, for use in ecological risk
assessment. The model is available at:
[www.epa.gov/ttn/fera/trim_fate.html](http://www.epa.gov/ttn/fera/trim_fate.html)

Other multi-media models are available here:
[www.epa.gov/ttn/fera/multi_related.html](http://www.epa.gov/ttn/fera/multi_related.html)

**8.4 Attachment 1. Excerpts from CFR on NAAQS Monitoring**

1.  **O~3~ (8-Hour)**

§ 50.10 National 8-hour primary and secondary ambient air quality
standards for ozone.

\(a\) The level of the national 8-hour primary and secondary ambient air
quality standards for ozone, measured by a reference method based on
appendix D to this part and designated in accordance with part 53 of
this chapter, is 0.08 parts per million (ppm), daily maximum 8-hour
average.

\(b\) The 8-hour primary and secondary ozone ambient air quality
standards are met at an ambient air quality monitoring site when the
average of the annual fourth-highest daily maximum 8-hour average ozone
concentration is less than or equal to 0.08 ppm, as determined in
accordance with appendix I to this part.

**8.4.2 PM~10~**

§ 50.6 National primary and secondary ambient air quality standards for
PM~10~.

\(a\) The level of the national primary and secondary 24-hour ambient
air quality standards for particulate matter is 150 micrograms per cubic
meter (µg/m 3 ), 24-hour average concentration. The standards are
attained when the expected number of days per calendar year with a
24-hour average concentration above 150 µg/m 3 , as determined in
accordance with appendix K to this part, is equal to or less than one.

\(b\) The level of the national primary and secondary annual standards
for particulate matter is 50 micrograms per cubic meter (µg/m 3 ),
annual arithmetic mean. The standards are attained when the expected
annual arithmetic mean concentration, as determined in accordance with
appendix K to this part, is less than or equal to 50 µg/m 3.

\(c\) For the purpose of determining attainment of the primary and
secondary standards, particulate matter shall be measured in the ambient
air as PM10 (particles with an aerodynamic diameter less than or equal
to a nominal 10 micrometers) by:

\(1\) A reference method based on appendix J and designated in
accordance with part 53 of this chapter, or

\(2\) An equivalent method designated in accordance with part 53 of this
chapter.

> **8.4.3 PM~2.5~**

§ 50.7 National primary and secondary ambient air quality standards for
PM2.5.

\(a\) The national primary and secondary ambient air quality standards
for particulate matter are 15.0 micrograms per cubic meter (µg/m3)
annual arithmetic mean concentration, and 65 µg/m3 24-hour average
concentration measured in the ambient air as PM2.5 (particles with an
aerodynamic diameter less than or equal to a nominal 2.5 micrometers) by
either:

\(1\) A reference method based on appendix L of this part and designated
in accordance with part 53 of this chapter; or

\(2\) An equivalent method designated in accordance with part 53 of this
chapter.

\(b\) The annual primary and secondary PM2.5 standards are met when the
annual arithmetic mean concentration, as determined in accordance with
appendix N of this part, is less than or equal to 15.0 micrograms per
cubic meter.

\(c\) The 24-hour primary and secondary PM2.5 standards are met when the
98th percentile 24-hour concentration, as determined in accordance with
appendix N of this part, is less than or equal to 65 micrograms per
cubic meter.

**8.4.4 Pb**

§ 50.12 National primary and secondary ambient air quality standards for
lead.

National primary and secondary ambient air quality standards for lead
and its compounds, measured as elemental lead by a reference method
based on appendix G to this part, or by an equivalent method, are: 1.5
micrograms per cubic meter, maximum arithmetic mean averaged over a
calendar quarter.

**8.4.5 NO~2~**

40 CFR § 50.11 National primary and secondary ambient air quality
standards for nitrogen dioxide.

\(a\) The level of the national primary ambient air quality standard for
nitrogen dioxide is 0.053 parts per million (100 micrograms per cubic
meter), annual arithmetic mean concentration.

\(b\) The level of national secondary ambient air quality standard for
nitrogen dioxide is 0.053 parts per million (100 micrograms per cubic
meter), annual arithmetic mean concentration.

\(c\) The levels of the standards shall be measured by:

\(1\) A reference method based on appendix F and designated in
accordance with part 53 of this chapter, or

\(2\) An equivalent method designated in accordance with part 53 of this
chapter.

\(d\) The standards are attained when the annual arithmetic mean
concentration in a calendar year is less than or equal to 0.053 ppm,
rounded to three decimal places (fractional parts equal to or greater
than 0.0005 ppm must be rounded up). To demonstrate attainment, an
annual mean must be based upon hourly data that are at least 75 percent
complete or upon data derived from manual methods that are at least 75
percent complete for the scheduled sampling days in each calendar
quarter.

**8.4.5 SO~2~**

40 CFR § 50.4 National primary ambient air quality standards for sulfur
oxides (sulfur dioxide).

\(a\) The level of the annual standard is 0.030 parts per million (ppm),
not to be exceeded in a calendar year. The annual arithmetic mean shall
be rounded to three decimal places (fractional parts equal to or greater
than 0.0005 ppm shall be rounded up).

\(b\) The level of the 24-hour standard is 0.14 parts per million (ppm),
not to be exceeded more than once per calendar year. The 24-hour
averages shall be determined from successive nonoverlapping 24-hour
blocks starting at midnight each calendar day and shall be rounded to
two decimal places (fractional parts equal to or greater than 0.005 ppm
shall be rounded up).

\(c\) Sulfur oxides shall be measured in the ambient air as sulfur
dioxide by the reference method described in appendix A to this part or
by an equivalent method designated in accordance with part 53 of this
chapter.

\(d\) To demonstrate attainment, the annual arithmetic mean and the
second-highest 24-hour averages must be based upon hourly data that are
at least 75 percent complete in each calendar quarter. A 24-hour block
average shall be considered valid if at least 75 percent of the hourly
averages for the 24-hour period are available. In the event that only
18, 19, 20, 21, 22, or 23 hourly averages are available, the 24-hour
block average shall be computed as the sum of the available hourly
averages using 18, 19, etc. as the divisor. If fewer than 18 hourly
averages are available, but the 24-hour average would exceed the level
of the standard when zeros are substituted for the missing values,
subject to the rounding rule of paragraph (b) of this section, then this
shall be considered a valid 24-hour average. In this case, the 24-hour
block average shall be computed as the sum of the available hourly
averages divided by 24.

**8.4.6 CO**

40 CFR § 50.8 National primary ambient air quality standards for carbon
monoxide.

\(a\) The national primary ambient air quality standards for carbon
monoxide are:

\(1\) 9 parts per million (10 milligrams per cubic meter) for an 8-hour
average concentration not to be exceeded more than once per year and

\(2\) 35 parts per million (40 milligrams per cubic meter) for a 1-hour
average concentration not to be exceeded more than once per year.

\(b\) The levels of carbon monoxide in the ambient air shall be measured
by:

\(1\) A reference method based on appendix C and designated in
accordance with part 53 of this chapter, or

\(2\) An equivalent method designated in accordance with part 53 of this
chapter.

\(c\) An 8-hour average shall be considered valid if at least 75 percent
of the hourly average for the 8-hour period are available. In the event
that only six (or seven) hourly averages are available, the 8-hour
average shall be computed on the basis of the hours available using six
(or seven) as the divisor.

\(d\) When summarizing data for comparision with the standards, averages
shall be stated to one decimal place. Comparison of the data with the
levels of the standards in parts per million shall be made in terms of
integers with fractional parts of 0.5 or greater rounding up.

**9. Assessment of Ambient Air Quality in Indian Country in the Absence
of Air Monitoring**

In Tribal Country where air monitoring has not been conducted, Tribes
may want to use non-monitoring methods to determine approximate
concentrations of air pollutants in order to decide if air monitoring is
necessary. Several methods, requiring various degrees of technical
expertise and financial resources, are identified in this section. These
methods include: 1) Internet-Based Tools, 2) Spatial Interpolation of
Existing Data, 3) Plume Dispersion Models, 4) Large-Scale,
Multi-Pollutant Models, and

5\) Smoke Dispersion Models.

The usefulness of the first two of these methods is that for some air
pollutants, concentrations typically do not vary sharply across fairly
large distances, so data collected at monitoring sites off the tribal
land can be informative of what the situation is within the tribal
boundary. This approach is best suited to ozone, PM2.5, and a few air
toxics that have such long residence times in the atmosphere and have
relatively constant concentrations over a large scale (e.g., carbon
tetrachloride and choloroform). Relying on data from monitors in other
areas is less reliable for other pollutants such as PMcoarse, CO, and
most air toxics. The Internet-Based Tools are ways to see data from
individual monitoring sites of interest. In addition to monitoring data
available through the Internet, industrial sources sometimes monitor for
certain pollutants to fulfill permit conditions or to meet PSD
requirements. The purpose of this monitoring is for sources to verify
modeling predictions that fenceline concentrations of these pollutants
will not exceed a certain level. Sources may be willing to share this
monitoring data with local tribes. These data could give tribes a rough
idea of the pollutant concentrations that exist in the area. These data
may also be available through the permitting agency to whom the data is
reported.

The third through fifth of the methods listed above are ways to estimate
air pollutant concentrations if emissions are known or can at least be
estimated. Plume Dispersion Models and Smoke Dispersion Models are
appropriate when the emission sources are relatively close to the area
where estimates of concentrations are needed, for example, when an
industrial plant is on tribal land or near its border. Large-scale,
multi-pollutant models are used to estimate the combined effects of
mobile, area, and stationary point sources over a large area, and are
referred to as "regional scale" models. They are most useful for
estimating ozone, PM2.5, and impacts of air pollutants on visibility.
Their advantage over using monitoring data from sites off the tribal
land is that it is possible to make projections into the future to see
how future emissions controls may improve air quality compared to
current concentrations

**9.1 Internet-Based Tools for Ambient Air Quality Assessment**

There are Internet based tools that can be useful when conducting
ambient air quality assessments in Indian country. These tools provide
information on the locations and types of current and historical ambient
air monitoring networks, monitoring data, emissions data from point and
area sources, and meteorological data. In addition, Internet tools are
available that assist with interpreting data. Web sites include a wide
variety of interactive maps and graphs. Modeling tools are also
available on the Internet that provide backward trajectories to
determine transport paths, and to model the dispersion of pollutants
released from a source on a particular day. These tools are accessible
to the public and are fairly easy to use. Becoming familiar with these
tools enables the tribal environmental professional to better understand
the local and surrounding airsheds, and to assess the potential for
pollution transport into Indian country. Much of the data obtained from
these tools have associated geospatial coordinates available on the Web
sites. When data are downloaded with geospatial coordinates they can be
integrated into a GIS map. GIS integration allows for a more
comprehensive and visual assessment. GIS integration is encouraged for
ambient air quality assessments. GIS software is available to federally
recognized tribes through the Bureau of Indian Affairs.

This section is intended to provide information that tribal
environmental professionals may find useful in determining issues that
may be of concern to them in the absence of monitoring data obtained
directly from their jurisdictional area. The information in this section
is not intended to be comprehensive. This section does not provide all
the information available from a particular Web site, or list all Web
sites that may be useful in assessing ambient air quality. Tribal
professionals are encouraged to explore beyond what is listed in this
document.

An initial air quality web based assessment should include:

-   Identifying existing and historical ambient air monitoring networks
    and their locations, as well as areas where data gaps exist

-   Obtaining all available air monitoring data from the surrounding
    areas

-   Identifying criteria and toxic emissions from area and point
    sources, and understanding the potential for transport of primary
    and secondary pollutants from those sources

-   Characterizing prevailing and seasonal wind patterns for both local
    and surrounding areas,

-   Determining wind transport paths on days when high pollutant
    concentrations were observed at monitoring sites (backward
    trajectories)

-   Determining pollutant dispersion from sources in the transport path
    on days when high concentrations were observed at monitoring sites

-   Identifying any health data that may indicate air quality problems

-   Integrating data into a GIS program

**[Recommended Web Sites]{.underline}**

<http://www.epa.gov/air/data> (EPA's AirData)

EPA's AirData Web site is one of the most useful sites to begin an
initial assessment. AirData provides summary monitoring data and
emission inventories data and gets most of its information from the Air
Quality System (AQS) and National Emissions Inventory (NEI) databases.
The site provides the information in both report and map format. Most
reports can be downloaded with map coordinates (latitudes, longitudes)
making data downloads GIS friendly. Emission Inventories for one or
several states can be downloaded and integrated into GIS maps. The same
is true for monitoring sites and summary monitoring data. You can also
get national/state/county on-line maps showing attainment/non-attainment
areas, source emissions by density or quantity, summary ambient air
monitoring data for criteria pollutants, AQI, and more.

[http://airnow.gov](http://airnow.gov/) (AIRNow)

The EPA, NOAA, NPS, tribal, state, and local agencies developed the
AIRNow web site to provide the public with easy access to national air
quality information. This web site offers daily AQI forecasts as well as
real-time AQI conditions for over 300 cities across the country, and
provides links to more detailed State and local air quality web sites.

[http://www.airnowtech.org](http://www.airnowtech.org/) (AIRNow-Tech)

Since 2002, the AIRNow-Tech web site has been used by local and state
agencies to query AIRNow observational data, issue forecasts, and manage
AIRNow program information. It is a one-stop portal to AIRNow data,
information, and events. Significant site enhancements have recently
been implemented to provide easier use and increased functionality. The
enhancements allow each authorized user from a particular agency to
manage personal information and customize settings to their individual
preferences and needs.

[http://www.epa.gov/AirExplorer/](http://www.epa.gov/airexplorer/)
(AirExplorer)

EPA's AirExplorer Web site provides access to detailed monitoring data
from monitoring sites that submit their data to AQS. For example,
AirData will provide the four highest concentrations and the annual mean
each year for PM-2.5 at a particular monitoring site. AirExplorer
provides access to all the 24-hour averages gathered throughout the
years at that same site. The data can be downloaded or viewed on-line.
Data has latitudes and longitudes and other information about how the
data was collected. AirExplorer also provides on-line interactive
mapping tools, air quality graphing tools, and benzene and PM-2.5
speciation data.

<http://vista.cira.colostate.edu/views/> (VIEWS)

The Visibility Information Exchange Web System (VIEWS) Web site provides
information obtained from the Interagency Monitoring of Protected Visual
Environments (IMPROVE) and other monitoring networks such as the Clean
Air Status and Trends Network (CASTNet). They are also integrating AQS
data into VIEWS. A typical IMPROVE site will collect data on PM10
concentrations, PM2.5 total concentrations, and concentrations of metal
and organic species bound to PM2.5 particles. CASTNet sites are related
to deposition and acid rain issues, but often have ozone analyzers
included. Data can be downloaded or viewed on-line. Although VIEWS is
primarily related to visibility issues, the site is also a tool for air
quality assessment outside of urban areas. Much of the regulatory
monitoring network data that are entered into AQS are focused in urban
areas. The IMPROVE and CASTNet systems are focused in rural areas,
national parks and wilderness areas. The VIEWS site also has tools that
allow intuitive and quantitative analysis. For example, in the annual
summary, backward trajectories section, you can select an IMPROVE site.
A chart will show up at the bottom of the page showing the particulate
concentrations in the selected year. You can click on the highest
concentrations and the Web site will provide backward trajectories for
that site on that day. Backward trajectories show the path the air took
prior to the high concentrations and are useful for determining
transport sources that may be adversely impacting air quality in an
area. There are several other summary/analytical tools available at this
site.

<http://www.arl.noaa.gov/ready.html> (HYSPLIT)

The National Oceanic and Atmospheric Administration (NOAA), Air
Resources Laboratory (ARL), Real-Time Applications and Display System
(READY) web site has a variety of tools available including backward
trajectories modeling software (HYSPLIT) and dispersion modeling
software (HYSPLIT), as well as tools that model meteorological
conditions at a selected latitude and longitude at the ground surface
and at elevations above the ground. The backward trajectories can be
integrated into GIS by downloading the endpoints file, modifying the
file slightly and using the right-click "Create Feature Class from XY
Table" function in ArcCatalog. Specific instructions are available at
the TAMS Center Web site. Backward trajectories are useful in
understanding transport issues by mapping the path air took prior to
entering the monitor.

<http://www.datafed.net/> (DATAFED)

### The goals of the DataFed site are to facilitate the access and flow of atmospheric data from providers to users, support the development of user-driven data processing value chains, and participate in specific application projects. Tools provided by DataFed include browsers and analysis tools for distributed monitoring data. DataFed also serves as data gateway for user programs (web pages, GIS, science tools). Currently DataFed is focused on the mediation of air quality data. Software provided for users include:

1\) Data Catalog for finding and browsing the metadata of registered
datasets,

2\) Dataset Viewer/Editor for browsing specific datasets, linked to the
Catalog,

3\) Data Views - geo-spatial, time, trajectory etc. views prepared by
the user,

4\) Consoles, collections of views on a web page for monitoring multiple
datasets, and

5\) Mini-Apps, small web-programs using chained web services (e.g. CATT,
PLUME)

<http://www.epa.gov/ttn/amtic> (AMTIC)

The Ambient Monitoring Technology Information Center (AMTIC) is operated
by EPA\'s Ambient Air Monitoring Group (AAMG). AMTIC contains
information and files on ambient air quality monitoring programs,
details on monitoring methods, relevant documents and articles,
information on air quality trends and non-attainment areas, and federal
regulations related to ambient air quality monitoring.

<http://www.epa.gov/ttn/airs/aqdatamart> (AQS Data Mart)

The AQS Data Mart is a project to make air quality data more accessible
and useful to the scientific and technical community. The Data Mart will
contain all of the raw and summary data from AQS for the previous 25
years. Also, it will contain AirNow data for AQS monitors for time
periods when AQS data is not available. All AirNow data will be purged
when it becomes one year old. The Data Mart will be accessible via the
internet in a variety of ways. The first will be via a commercial
business intelligence tool called Business Objects. This software allows
users to explore the database, build queries, and (to a limited extent)
export data. We have a limited number of licenses for this software, and
it is not the ideal way to export large amounts of data. For that
reason, we will also deploy web service query capabilities. The EPA\'s
Central Data Exchange (CDX) will host web services that allow users to
query the Data Mart. We will also provide a web-page interface for you
to build queries and identify where you would like results returned. You
can use the CDX web services specifications to build the consumption of
the Data Mart web services directly into your own application. All web
service requests will be authenticated so users must be registered with
CDX. We will post more detailed instructions on how to register for and
use the web services as they become available. Finally, EPA is planning
to connect some of our already existing data retrieval web pages to the
Data Mart. That is, in the future AirExplorer, AQS Query, and perhaps
AirData will all use the Data Mart as their source for air quality data.
OAQPS expects a general release of Data Mart at the end of March 2006.

**9.2 Spatial Interpolation of Existing Data**

The need for spatial (geostatistical) interpolation models in the
regulatory environment has grown in the past few years. Spatial
interpolation as applied to air monitoring data is loosely defined as
the procedure for estimating ambient air concentrations at unmonitored
locations in a certain area based on available observations within the
proximity of the area. The justification underlying spatial
interpolation is the assumption that points closer together in space are
more likely to have similar values than points more distant. EPA and
States use spatial interpolation to review decisions on monitoring
network design and to predict the efficacy of emission control programs.
Due to the limited number of monitoring sites across the country,
especially for pollutants that cover a large area, such as ozone and
fine particles, there is a need to use spatial interpolation to predict
ambient concentrations in unmonitored locations.

Geostatistical interpolation methods are stochastic methods, with
kriging being the most well-known representative of this category.
Conceptually, the goal of kriging is to find linear combinations of the
data that are optimal and consistent with the observed data points. In
particular, kriging is a statistical model that produces both a spatial
surface of predictions for the process of interest as well as the
uncertainty associated with those estimates. Kriging calculates weights
for measured points in deriving predicted values for unmeasured
locations. With kriging, however, those weights are based not only on
distance between points, but also on the variation in measured
concentrations as a function of distance. A major benefit of the various
forms of kriging is that estimates of the model's prediction uncertainty
can be calculated, considered in the analysis, and plotted along with
the predicted values. Such uncertainty information is an important tool
in the spatial decision making process.

There are three main kriging methods and each has unique assumptions
that must be met. "Simple" kriging assumes that there is a known
constant mean, that there is no underlying trend, and that all variation
is statistical. "Ordinary" kriging is similar except it assumes that
there is an unknown constant mean that must be estimated based on the
data. "Universal" kriging differs from the other two methods in that it
assumes that there is a trend in the surface that partly explains the
data's variations. This should only be utilized when it is known that
there is a trend in the data.

Ordinary kriging, which is addressed in this section, is a version of
kriging that assumes the mean is constant but unknown across the spatial
domain of interest. Ordinary kriging defines the process as follows:

**Z(x,y) = u + e(x,y) ,**

**u** = the overall, large-scale mean of the process across the spatial
domain; and

**e(x,y)** = the small-scale random fluctuation of the process within
the spatial domain.

In practice, ordinary kriging, for the purpose of spatial interpolation,
is implemented via the following five steps:

**Step 1: Build the Data Set**

Often it is the case that an initial data set will require
pre-processing to generate analysis data that better match the spatial
process of interest with respect to temporal scale. This can be
accomplished via some sort of temporal averaging of the initial data.
For example, a data set of 1-hour ozone concentrations might be averaged
in some manner to yield 8-hour concentrations for analysis. When
pre-processing an initial data set via temporal averaging, some
consideration must be given to the temporal completeness of the
resulting average. If the initial data used to generate an endpoint such
as an annual average are somehow temporally incomplete, the calculated
endpoint may be biased in some manner. For example, many air pollutants
exhibit significant seasonal fluctuations, so an annual average
estimated from only a single quarter's worth of data (e.g., January
through March) may not be representative of the true year-long average.

**Step 2: Summarize and Understand the Data**

Once the spatial analysis data set has been built, it is important to
generate some initial summaries of the available data prior to analysis
in order to obtain a better understanding of its empirical structure and
behavior. Reasonable summaries include, but are not limited to,
graphical information systems (GIS) maps of the spatial domain and
available data locations, a histogram of the overall data distribution,
and summary statistics such as the data's mean, standard deviation, and
various percentiles (e.g., minimum, median, maximum, etc.).

**Step 3: Conduct a Variogram Analysis**

Once the analysis data set has been built and explored to gain some
basic understanding, the kriging modeling exercise can begin. The
exercise begins by conducting a variogram analysis. This analysis
typically consists of first generating an empirical variogram and then
fitting a parametric model that adequately captures the structure of the
empirical variogram. Ultimately, the estimated parameters of the
variogram will be input into for the kriging spatial prediction and
uncertainty formulas from which a spatially interpolated surface is
generated. In other words, once you have chosen a satisfactory variogram
model, you then use that model as an input to the actual kriging
process.

The most common models used in the variogram modeling process are:
linear, spherical, exponential, rational quadratic, wave (or
hole-effect), power, and Gaussian. Of these seven variogram models,
three are used most commonly: spherical, exponential, and Gaussian.
Exponential models fit best when the spatial autocorrelation decreases
exponentially with increasing distance. Spherical models provide a
better fit when spatial autocorrelation decreases to a point after which
it becomes zero. Gaussian variograms tend to have an "S" shape, with a
gradual upward slope at short distances, followed by a sharper upward
slope at middle distances and, finally, by another gradual upward slope
at long distances. To determine which of these models best fit the data,
attempt to fit the data using all of these models. If the fitting
procedure fails to converge for a given covariance function, remove it
from consideration. By considering several variogram models, one can
choose the model that best fits the data.

Various software packages, including Surfer, GMS, SAS, S-Plus, and
others will compute the empirical variogram and assist in the modeling
process. Among these, two statistical packages are noteworthy: SAS and
S-Plus. Both packages have different strengths and weaknesses. SAS, in
general, appears to be more flexible than S-Plus, but it requires
understanding of SAS programming. SAS does not provide much in the way
of automatic defaults or computation of parameters, though standard
parameter estimation functions can be used, in conjunction with the
variogram functionality, to model the process. S-Plus, on the other
hand, with the addition of its spatial module, has been designed to
minimize the level of technical knowledge required on the part of the
user. S-Plus provides a series of menu-accessed functions to process a
data set. In many cases, these functions will cause parameters to
default to functional values if they are not specified by the user.

**Step 4: Apply Spatial Prediction and Uncertainty Formulas**

In the previous step, the spatial structure associated with the data was
modeled using a variogram analysis. That variogram model is now applied
to the task of spatial prediction. The current step of applying the
variogram analysis results is relatively straightforward, if appropriate
software is available for applying the equations. Surfer, GMS, S-Plus,
SAS, and several other software packages have the capability to compute
kriging estimates given data and a variogram function. Using these
software packages, kriging predictions and standard errors can be
generated everywhere in either a default or user-defined grid.

**Step 5: Evaluate Model Performance**

There are two primary ways to evaluate model performance. The first
method is to map the interpolated concentrations and compare them to
observed monitored values. Observed and estimated values at monitor
sites should be close but do not need to match exactly. Allowing some
variation between observed and estimated values at monitoring locations
may give better results for unmonitored areas. The second method is to
review the uncertainty estimates generated by the model. The output from
the kriging model consists of both estimated values as well as
uncertainty of the estimated values (e.g., standard errors). Locations
within the vicinity of several monitors should have lower standard
errors than areas with a sparse set of monitors. Also, there may be
higher standard errors along the boundaries of the local domain.
Including additional monitoring information outside the local domain
should improve the standard errors along the boundaries of the domain.

A more detailed description of the kriging process can be found in the
EPA report titled "Developing Spatially Interpolated Surfaces and
Estimating Uncertainty", EPA-454/R-04-004, November 2004.

Spatial Interpolation Contact: Glenn Gehring, TAMS, (702) 784-8269

**9.3 Plume Dispersion Models**

These types of models would be useful to tribes in estimating the
concentrations of pollutants impacting air quality on their reservations
from nearby large stationary sources. In order to run these models, a
tribe needs to know the emission rates of pollutants of concern (e.g.,
NOx, SO2, and PM) from each source, and needs to have the appropriate
meteorological data required by the model. These models can also be used
to determine the improvements in air quality which could be achieved by
placing emission controls on stationary sources.

1.  **AERMOD**

The AERMOD Modeling System (AERMOD) is a steady state Gaussian plume
dispersion model whose formulation is based on planetary boundary layer
principles. The modeling system consists of three program - a dispersion
program (AERMOD), a terrain processor program (AERMAP), and a
meteorology processor program (AERMET). AERMET reads in hourly surface
meteorological data, upper air data and surface characteristics and
generates a surface file and a profile file. AERMAP extracts terrain
elevations from U.S. Geological Survey Digital Elevation Model (DEM)
files (e.g., 10-meter and 7.5 minute) and calculates height scales based
on a user provided location coordinates (i.e., Universal Transverse
Mercator \[UTM\], NAD27). Using the files generated from AERMAP and
AERMET, source information, and specific model run options within the
AERMOD dispersion program, inert air pollutant concentrations are
estimated at designated locations and for specified averaging periods.

The AERMOD dispersion program simulates transport and dispersion for
point, area and volume sources. Sources may be located in a rural or
urban area. The dispersion model also accounts for wake effects using
the PRIME building downwash algorithm. An estimate of concentration
should only be made for a source-to-receptor distance of less than 50
kilometers. The AERMOD Modeling System is expected to be promulgated as
an U.S. EPA recommended model and codified in the Guideline on Air
Quality Models, Appendix W to 40 CFR Part 51. With AERMOD promulgation,
the Industrial Source Complex Short Term 3 (ISCST3) dispersion model
will no longer be recognized as a preferred model.

**9.3.2 AERSCREEN**

A screening version of the AERMOD Modeling System is under development.
Unlike AERMOD, AERSCREEN will use a screening meteorological data set
with the dispersion program to estimate maximum hourly concentrations.
The AERSCREEN predicted hourly concentrations are expected to be higher
than the maximum 1-hour concentrations predicted by the AERMOD
dispersion program. Scaling factors are applied to the AERSCREEN 1-hour
concentration to obtain concentrations for other averaging periods.
AERSCREEN will replace the SCREEN3 Model.

2.  **CALPUFF**

The CALPUFF Modeling System (CALPUFF) is a multi-layer, multi-species
non-steady-state puff dispersion modeling system that simulates the
effects of time- and space-varying meteorological conditions on
pollutant transport, transformation, and removal. CALPUFF contains three
primary programs - CALMET, CALPUFF and CALPOST. CALMET reads in
mesoscale meteorology from observations and/or from predictions by
prognostic meteorological models (e.g. MM5 and RUC) and develops hourly
meteorological variables on a three-dimensional gridded modeling domain.
With the output from CALMET, source information, and specific model run
options, CALPUFF is used to generate hourly concentration or deposition
flux files. CALPOST is employed to process the CALPUFF output files to
estimate concentration impacts at Federal Class I area and impacts to
Air Quality Related Values (AQRV) such as visibility.

The U.S. EPA recommends the use of the CALPUFF Modeling System for
source-to-receptor distances greater than 50-kilometers. CALPUFF is also
recommended by the Inter Agency Workgroup on Air Quality Modeling
(IWAQM) for use in evaluating impacts on visibility and deposition in
Federal Class I areas. On case-by-case basis, the CALPUFF Model can be
used in a near field application, and during stagnant or complex wind
conditions. The CALPUFF Modeling System has been promulgated for
regulatory application in the Guideline on Air Quality Models, Appendix
W to 40 CFR Part 51. Appendix A contains more information on the AERMOD
and CALPUFF models.

Plume Dispersion Model Contact: Herman Wong, EPA Region 10, (206)
553-4858

3.  **Large Scale Multi-Pollutant Models**

Large-scale, multi-pollutant models are used to estimate the combined
effects of many emission mobile, area, and stationary point sources over
a large area, and are referred to as "regional scale" models. They are
most useful for estimating ozone, PM2.5, and impacts of air pollutants
on visibility. These types of models require large amounts of source
emissions data and meteorological data, and require specialized
technical expertise. More relevant to the tribes is that these models
have been used by the Regional Planning Organizations, EPA, and some
individual states. As an alternative to running these models, tribes
should consider accessing the modeling results generated by other
agencies that cover their reservations.

1.  **Community Multi-scale Air Quality (CMAQ) Model**

The CMAQ modeling system has been designed to approach air quality as a
whole by including state-of-the-science capabilities for modeling
multiple air quality issues, including tropospheric ozone, fine
particles, toxics, acid deposition, and visibility degradation. Hence,
CMAQ combines the scientific expertise from each of these areas into one
'community model'. In addition to being a multi-pollutant model, CMAQ
was also designed to have multi-scale capabilities so that separate
models were not needed for urban and regional scale air quality
modeling. The target grid resolutions and domain sizes for CMAQ range
spatially and temporally over several orders of magnitude. With the
temporal flexibility of the model, simulations can be performed to
evaluate longer term pollutant transport, as well as short-term
transport from localized sources. With the model's ability to handle a
large range of spatial scales, CMAQ can be used for urban and regional
scale model simulations.

The CMAQ modeling system simulates various chemical and physical
processes that are thought to be important for understanding atmospheric
trace gas transformations and distributions. The CMAQ modeling system
utilizes three separate modeling components: a meteorological model
(typically MM5) for the description of atmospheric states and air mass
motions, an emissions model (typically SMOKE) for man-made and natural
emissions that are injected into the atmosphere, and a
chemistry-transport model for simulation of the chemical transformation
and fate (the CCTM model). The meteorological and emissions model
outputs are required inputs into the CMAQ chemistry-transport model,
hence this is viewed as a modeling system.

CMAQ's current structure is based on a modularity level that
distinguishes between its main driver, science modules, data estimation
modules, and control/utility subroutines in the model. This enables the
attainment of higher resolution than commonly seen in previous models.
The distinction remains at a division between the science models
(including submodels for meteorology, emissions, chemistry-transport
models), and analysis and visualization subsystems. Typically the CMAQ
modeling system is run on a multi-processor Linux or UNIX computer
cluster environment and usually requires at minimum over 1 terabyte of
storage capacity.

Current CMAQ and SMOKE model codes and training are available from the
CMAS Center at: http://www.cmascenter.org/

Current MM5 model code and training is available from UCAR at:

http://www.mmm.ucar.edu/mm5/

CMAQ Contact: Robert Kotchenruther, EPA Region 10, (206) 553-6218

2.  **The NATA Model**

The 1999 National Air Toxics Assessment (NATA) is a nationwide study of
potential inhalation exposures and health risks associated with 133 air
toxics and diesel particulate matter (diesel PM), based on emissions
data for 1999. The initial national-scale assessment is comprised of
four major technical components: 1) compiling a national emissions
inventory of air toxics and diesel PM for the year 1999 from outdoor
sources; 2) estimating 1999 air toxics and diesel PM ambient
concentrations; 3) estimating 1996 population exposures; 4)
characterizing potential public health risks.

The purpose of the NATA is to gain a better understanding of the air
toxics problem. Specifically, the goal of the assessment is to assist
in: 1) identifying air toxics of greatest potential concern in terms of
contribution to population risk; 2) characterizing the relative
contributions of various types of emission sources to air toxics
concentrations and population exposures; 3) setting priorities for
collection of additional air toxics data and research to improve
estimates of air toxics concentrations and their potential public health
impacts; 4) tracking trends in modeled ambient air toxics concentrations
over time; and, 5) measuring progress toward meeting goals for
inhalation risk reduction from ambient air toxics.

The NATA website:
[www.epa.gov/ttn/atw/nata1999](http://www.epa.gov/ttn/atw/nata1999)

**(This needs to be updated for the public access site)**

NATA Contact: Ted Palma, OAQPS, (919) 541- 5470

**9.5 Smoke Dispersion Models**

1.  **BlueSky Model**

BlueSky is a modeling framework which brings together the latest state
of the science for modeling fuels, fire, smoke, and weather into one
centralized processing system. It makes sophisticated emission,
dispersion and weather prediction models and model output easily
accessible to the operational fire and air quality management
communities. The modeling framework is designed to predict cumulative
impacts of smoke from forest, agricultural, and range fires, including
both prescribed fire and wild fire. To view BlueSky output and
publications go to <http://www.fs.fed.us/bluesky>.

The BlueSky system was designed as a tool to aid land managers using
fire on the landscape in making go/no-go/go slow decisions with regard
to smoke management. BlueSky provides hourly predictions of PM2.5
concentrations based on information available from multi-agency tracking
systems such as FASTRACS and RAZU, and from wildfire 209 reports.
Trajectory predictions available in BlueSky RAINS indicate the direction
and height of smoke plumes 12 hours out in time.

Centralized collection and processing of model data relieves the user of
the need to download data and learn complex modeling systems. It also
allows for analysis of multiple burns and wildfires so that air quality
managers can see the combined impacts within shared airsheds. Output is
posted to the web daily for easy access by burners, air resource
specialists, and the public. In order to provide quality output, the
BlueSky system relies on the collaboration of many agencies at the
federal, state, and local level.

The BlueSky modeling framework has 5 components. Although the specific
models used within each component may change over time as the modeling
science advances, the basic structure will remain the same. As of June
2005, fire characteristics are processed through the Emissions
Production Model (EPM) to give emission estimates of particulates
(PM~2.5~, PM~10~, and total PM), carbon compounds (CO, CO~2~, CH~4~,
non-methane hydrocarbons), and heat generated. The emission estimates
from EPM, along with meteorology from MM5, are input data to the CALPUFF
dispersion model and the HYSPLIT trajectory model. The BlueSky system
framework merges meteorology with emission estimates to yield an
integrated regional-scale analysis of smoke dispersion and aerosol
concentrations.

The BlueSky concentration fields and trajectories are displayed on the
website in the Rapid Access INformation System (RAINS); a Geographic
Information System (GIS) application developed by the US EPA.
Integrating BlueSky with RAINS, allows the user to zoom in on areas of
interest, step through time, and overlay GIS data layers such as
sensitive receptors, boundaries, roads, rivers and topography. Primary
inputs to BlueSky include weather, fire characteristics, and fuels. This
section briefly describes the sources for each of these input
parameters.

*Weather **-- ***Predictions of wind speed and direction as well as
mixing height are required to determine smoke trajectories and PM2.5
concentrations. Weather inputs come from the MM5 mesoscale
meteorological model. See Appendix X for more detail on the MM5.

*Fire Characteristics **--*** In order to arrive at an accurate
prediction of smoke emissions it is necessary to get detailed
information about the size, location and timing of a prescribed burn or
wildfire. This information is retrieved from interagency reporting
systems such as FASTRACS in the Pacific Northwest, RAZU in Montana and
Idaho and will soon be available from ***PFIRS*** in California.
Alternative ways of providing input on prescribed burns for BlueSky are
also being developed. Wildfire information is also accessed
automatically each day from 209 reports available from the National
Interagency Fire Center (NIFC).

*Fuels **-- ***Fuel model and fuel loading information is essential to
emissions modeling. BlueSky uses fuel characteristics derived from the
Fuel Characteristic Classification System (FCCS) to arrive at this
information. For more information about FCCS go to
<http://www.fs.fed.us/pnw/fera/fccs/index.html>.

Emissions and Dispersion Modeling

Emissions are computed using Consume/EPM v1.03 which calculates the heat
release rate and emissions for particulate matter and carbon compounds
as a function of time since fire ignition. These emission values are
input data for CALPUFF v5.711 which calculates the dispersion and plume
rise. Trajectories are computed using the HYSPLIT model. HYSPLIT uses
the full 3-dimensional wind field for computational purposes but does
not include any heat or buoyancy effects from the fire.

Web Products

BlueSky output products can be viewed as animations or as static hourly
images using BlueSky RAINS. BlueSky output can be viewed as either a
Java Script animation (recommended for high speed internet connections)
or Gif animation (recommended for dial up internet connections). Users
must select a resolution and the type of animation then click on the
appropriate square.

The animations show model predicted PM2.5 concentrations and wind flow
patterns at the surface. Animations are useful for getting a big picture
look at predicted PM2.5 over time for all the fires and burns in the
system for a given run. While it is possible to stop the loop and look
at individual frames, it is not possible to zoom in or add information
to the images. At the bottom of the Animation page is a dropdown menu
which allows the user to select animations from any BlueSky run going
back to September of 2002.

BlueSky Contact: Sim Larkin, USFS, (206) 732-7849

2.  **BlueSky/RAINS**

RAINS is the Rapid Access Information System developed by EPA Region 10.
RAINS takes advantage of Geographic Information System (GIS) technology
to display maps and data via the internet. BlueSky/RAINS builds on the
RAINS concept as an avenue for making BlueSky model output available to
users in an interactive ***ArcIMS*** format. BlueSky/Rains brings the
output from the modeling framework into an interactive GIS environment
so that the user can optimize the display for his or her needs. Displays
can be zoomed in to the individual project level or out to the regional
level. In addition to PM2.5 concentrations, trajectories showing the
direction, height, and timing of smoke movement can be shown.
Meteorological output for a number of parameters is also available. Maps
showing roads, rivers, boundaries, and a variety of smoke sensitive
receptors can be selected. To access BlueSkyRAINS go to
[http://www.blueskyrains.org](http://www.blueskyrains.org/) .

BlueSky/RAINS Contact: Rob Wilson, EPA Region 10, (206) 553-1675

**10. Other Air Quality Management Program Elements**

\[This section is intended to give first steps and other information
regarding development of emissions inventories and source reporting,
adoption of source emissions standards, adoption and operation of
permitting programs, etc. for the benefit of tribes that are considering
or are in the early stages of involvement in such programs.\]

(to be completed)

**Appendix A. Examples of Tribal Air Monitoring Projects**

  --------------- --------------- --------------- -------------- ------------------ ------------ -------------- --------------- ----------------------------------
  **Name of       **Tribe**       **Project       **Pollutants   **Description of   **QA Plan?** **Location of  **Data          **Results/Conclusions/Outcomes**
  Project**                       Objectives**    Monitored**    Project/Budget**                Data**         Analysis/       
                                                                                                                Assessment**    

  Sioux           Spirit Lake     Measure ambient VOCs and                          Yes                         EPA reviewed    Monitored HAPs were far below RfCs
  Manufacturing   Tribe, Fort     air toxics in   Carbonyls                                                     data that was   for inhalation. Tribe wishes to
  Air Toxics      Totten, ND      proximity of    using UATMP                                                   supplied by     conduct follow-up short-term
  Monitoring                      manufacturing   canisters and                                                 monitoring      project after installation of
  Project                         plant and       Puf sampler,                                                  completed by    controls at source.
                                  community       met monitor                                                   Tribe and       
                                                                                                                analyzed by EPA 
                                                                                                                contractor,     
                                                                                                                compared values 
                                                                                                                to IRIS RfC     

  Aquinnah, MA    Wampanoag Tribe Long term       Ozone; IMPROVE                    Yes          AIRS IMPROVE                    
  (Martha's       of Gay Head     measurement of  monitor; met                                   web page                       
  Vineyard)       Aquinnah, MA    air pollutants                                                                                
  Ambient Air                     and regional                                                                                  
  Monitoring site                 haze                                                                                          

  Indian Island,  Penobscot       Long term       Ozone; SO2;                       Yes          AIRS IMPROVE                    
  ME Ambient Air  Nation, Indian  measurement of  IMPROVE                                        web page                       
  Monitoring site Island, ME      air pollutants  monitor; met                                                                  
                                  and regional                                                                                  
                                  haze                                                                                          

  Carrabassett    Penobscot       to collect data NADP monitor                                   NADP web page                   
  Valley, ME NADP Nation, Indian  on the                                                                                        
  site            Island, ME      chemistry of                                                                                  
                                  precipitation                                                                                 
                                  for monitoring                                                                                
                                  of long-term                                                                                  
                                  trends                                                                                        

  Baseline air                    Measure ambient Two IMPROVE    These monitoring   Yes:         Monitors began Expectations:    
  vs. Fort James                  air before and  monitors run   devices are                     collecting     The reason for  
  BioMass Boiler                  after new       concurrently   currently being                 comparison     this study is   
                                  BioMass boiler  one            operated by the                 data on        due to the      
                                  at nearby paper off-island,    tribe via previous              01/12/06.      nature of       
                                  making plant    one on-island, grant awards                    Study will     demolition      
                                  begins to burn  SO2 and Ozone                                  conclude on    debris:         
                                  demolition      monitors                                       07/24/06.EPA   allowable       
                                  debris          co-located                                     and Penobscot  percentage of   
                                                  with Met                                       will review    toxins to be    
                                                  station on the                                 data at that   included in 500 
                                                  reservation                                    time.          tons per day    
                                                                                                                combustion is   
                                                                                                                5%. Lead-based  
                                                                                                                paint alone may 
                                                                                                                cause emissions 
                                                                                                                to exceed EPA   
                                                                                                                allowable       
                                                                                                                levels.         

  Real Time Air   Aroostook Band                  Ozone, Sulfur  EPA Grant          In Draft     AIRS, Tribal                    
  Monitoring      of Micmac                       Dioxide,                                       web page,                      
  Site, Presque   Indians,                        Nitrogen                                       CamNet web                     
  Isle , ME       Presque Isle,                   Dioxide,                                       page                           
                  ME                              Carbon                                                                        
                                                  Monoxide,                                                                     
                                                  Carbon                                                                        
                                                  Dioxide,                                                                      
                                                  PM2.5, Haze                                                                   
                                                  Camera, Met                                                                   

  Air Monitoring  Passamaquoddy   Long term       Ozone, Met                        Yes          AIRS                            
  Site Route 190  Pleasant Point  measurement of                                                                                
  Perry, ME                       air pollutants                                                                                

  Wolapomomqot    Passamaquoddy   to collect data NADP monitor;                                  NADP web page                   
  Ciw Wocuk air   Indian Township on the          MDN monitor                                                                   
  monitoring site                 chemistry of                                                                                  
                                  precipitation                                                                                 
                                  and mercury for                                                                               
                                  monitoring of                                                                                 
                                  long-term                                                                                     
                                  trends                                                                                        

  ITEC            Criteria        Collect ambient O3, NOy, NOx,  7 various          3 ambient    EPA AQS        ITEC and EPA-R6 Ongoing with annual EPA-R6 review
                  pollutant       air monitoring  CO, SO2, PM10  pollutant          air                                         
                  monitoring      data meeting    (lo vol) and   monitoring sites   monitoring                                  
                                  EPA monitoring  PM10           in OK and NM       QAPPs                                       
                                  and QA          continuous,                                                                   
                                  requirements    PM2.5 (lo vol)                                                                
                                                  and PM2.5                                                                     
                                                  continuous                                                                    
                                                  (including                                                                    
                                                  FDMS), and met                                                                
                                                  monitoring                                                                    
                                                  data                                                                          

  ITEC            IMPROVE and NH3 Collect IMPROVE IMPROVE and    1 IMPROVE          1 IMPROVE    VIEWS and EPA  ITEC and CENRAP Ongoing with 5 year EPA-R6 review
                  monitoring      and NH3 air     NH3 monitoring monitoring site    monitoring   AQS                            
                                  monitoring data data           and 1 NH3          QAPP? and 1                                 
                                  meeting IMPROVE                monitoring site    NH3                                         
                                  and NH3                                           monitoring                                  
                                  monitoring and                                    QAPP                                        
                                  QA requirements                                                                               

  ITEC            CASTNET and Hg  Collect CASTNET CASTNET and Hg 1 CASTNET          1 CASTNET    EPA CAMD       ITEC, CAMD,     Ongoing with 5 year EPA-R6 review
                  monitoring      and Hg          monitoring     monitoring site    monitoring   CASTNET and    NADP and EPA-R6 
                                  monitoring data data           and 2 Hg           QAPP and 1   NADP Hg                        
                                  respectively                   monitoring sites   Hg                                          
                                  meeting CASTNET                                   monitoring                                  
                                  and Hg                                            QAPP                                        
                                  monitoring and                                                                                
                                  QA requirements                                                                               

  Quapaw Tribe    Tar Creek       Collect ambient Pb (hi vol),   4 sites            1 ambient    EPA AQS        Quapaw Tribe    Temporarily ongoing with ongoing
                  (Superfund      air monitoring  PM10 (hi vol),                    air                         and EPA-R6      EPA-R6 review
                  Site) Air       data meeting    PM10                              monitoring                                  
                  Monitoring      EPA monitoring  continuous,                       QAPP                                        
                  Project (TCAMP) and QA          PM2.5                                                                         
                                  requirements    continuous and                                                                
                                                  silica (SiO2)                                                                 
                                                  PM10 (lo vol)                                                                 
                                                  monitoring                                                                    
                                                  data                                                                          

  Quapaw Tribe    Criteria        Collect ambient O3, NOy, PM2.5 1 site             1 ambient    EPA AQS        Quapaw Tribe    Ongoing with annual EPA-R6 review
  (TCAMP          pollutant       air monitoring  FRM and                           air                         and EPA-R6      
  Background      monitoring      data meeting    continuous,                       monitoring                                  
  Site)                           EPA monitoring  PM10                              QAPP                                        
                                  and QA          continuous and                                                                
                                  requirements    met monitoring                                                                
                                                  data                                                                          

  Jemez Pueblo    Criteria        Collect ambient O3, CO, PM10   1 site             2 ambient    EPA AQS        Jemez Pueblo    Ongoing with annual EPA-R6 review
                  pollutant       air monitoring  continuous,                       air                         and EPA-R6      
                  monitoring      data meeting    PM2.5 (lo vol)                    monitoring                                  
                                  EPA monitoring  and continuous                    QAPPs                                       
                                  and QA          (FDMS), and                                                                   
                                  requirements    met monitoring                                                                
                                                  data                                                                          

  (Western)       Criteria        Collect ambient O3, PM10 (lo   1 site             2 ambient    EPA AQS        Delaware Nation Ongoing with annual EPA-R6 review
  Delaware Nation pollutant       air monitoring  vol), PM2.5                       air                         and EPA-R6      
                  monitoring      data meeting    (lo vol) and                      monitoring                                  
                                  EPA monitoring  met monitoring                    QAPPs                                       
                                  and QA          data                                                                          
                                  requirements                                                                                  

  Sac and Fox     Criteria        Collect ambient O3, PM2.5 (lo  1 site             2 ambient    EPA AQS        Sac and Fox     Ongoing with annual EPA-R6 review
  Nation          pollutant       air monitoring  vol) and met                      air                         Nation and      
                  monitoring      data meeting    monitoring                        monitoring                  EPA-R6          
                                  EPA monitoring  data                              QAPPs                                       
                                  and QA                                                                                        
                                  requirements                                                                                  

  Alabama         CASTNET         Collect CASTNET CASTNET        1 CASTNET          1 CASTNET    EPA CAMD       Alabama         Ongoing with 5 year EPA-R6 review
  Coushatta Tribe monitoring with monitoring data monitoring     monitoring site    monitoring   CASTNET        Coushatta       
                  future          meeting CASTNET data                              QAPP                        Tribe, CAMD and 
                  regulatory O3   monitoring and                                                                EPA-R6          
                  and NOy         QA requirements                                                                               
                  monitoring                                                                                                    
  --------------- --------------- --------------- -------------- ------------------ ------------ -------------- --------------- ----------------------------------

[^1]: The available strategic guidance (excluding technical guidance on
    monitor operations and maintenance) includes the following
    documents, and perhaps others at the individual Regional Office
    level:

    4-page section titled "Tribal Air Quality Management" in the *Final
    National Program and Grant Guidance for Fiscal Years 2006-2008*,
    April 27, 2005.

    Memo from Jeffrey R. Holmstead, "Criteria for Providing Funds to
    Tribes from the State and Tribal Grant Assistance Appropriation for
    103 and 105 Grants," January 27, 2005.

    ***"***[Menu Item***:***]{.smallcaps} Air Quality Monitoring
    Activities***,"*** in *The Tribal Air Grant Framework - A Menu of
    Options For Developing Tribal Air Grant Work Plans and Managing
    Grants for Environmental Results*, September 2004.
    http://yosemite.epa.gov/R10/AIRPAGE.NSF/283d45bd5bb068e68825650f0064cdc2/e34950b285534aa988256dfe0063be55/\$FILE/The%20TRIBAL%20AIR%20GRANTS%20FRAMEWORK%20final.pdf

    Guidance for Conducting: TRIBAL AIR QUALITY ASSESSMENTS, U.S. EPA
    Region 10, April 15 2005.

[^2]: In FY2005, EPA proposed to Congress that there be separate amounts
    of air grant funding for states and tribes. EPA observes these two
    separate ceilings in its operating plan under the enacted FY2005
    budget. EPA has proposed the same separation for FY2006, and EPA has
    issued grant and technical guidance for FY2006 based on this
    separation. In FY2005, \$ 11.1 million is available for tribal air
    management, see http://www.epa.gov/ocfo/budget/2005/2005bib.pdf. The
    proposed FY2006 budget provides \$ 11 million, see
    http://www.epa.gov/ocfo/budget/2006/2006bib.pdf.

[^3]: For example, the cost of lab and shipping services for an IMPROVE
    protocol site is \$33,000 per year.