& EPA
United .States
Environmental Protection
Agency
55
. Office of Air Quality
Planning and Standards
Research Triangle Park, NC 27711
EPA-450/4-91-033 .
November 1991
ENHANCED OZONE MONITORING
NETWORK DESIGN AND .NV|RONME(OA,
SITING CRITERIA PROTECTS
GUIDANCE DOCUMENT
AGENCY
ALIAS, TEXAi
UBRMtY
-------
-------
ENHANCED OZONE MONITORING NETWORK DESIGN AND SITING CRITERIA
GUIDELINE DOCUMENT
FINAL REPORT
Work Assignment 21
EPA Contract: 68DO0125
SUBMITTED TO:
Mr. Neil Berg
Office of Air Quality Planning and Standards
Technical Support Division
Monitoring and Reports Branch
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
PREPARED BY:
Radian Corporation
P.O. Box 13000
Research Triangle Park, North Carolina 27709
-------
-------
DISCLAIMER
The information in this document has been funded wholly or in
part by the United States Environmental Protection Agency under
Contract No. 68-DO-0125 to Radian Corporation. It has been
subject to the Agency's peer and administrative review, and it
has been approved for publication as an EPA document. Mention of
trade names or commercial products does not constitute
endorsement or recommendation for use.
tl«.030
11
-------
TABLE OF CONTENTS
Page
LIST OF ABBREVIATIONS AND ACRONYMS vii
1.0 INTRODUCTION 1-1
1.1 REGULATORY BACKGROUND & PURPOSE 1-1
1.2 GENERAL APPROACH 1-3
2.0 NETWORK DESIGN 2-1
2.1 INTRODUCTION 2-1
2.2 PAMS SITE TYPES 2-2
2.2.1 Site Type (1) - Upwind Background .... 2-6
2.2.2 Site Type (2) - Downwind Edge of
Maximum Precursor Emissions 2-6
2.2.3 Site Type (3) - Downwind Fringe of MSA . 2-7
2.2.4 Site Type (4) - Maximum Ozone
Concentration - Primary Downwind
Direction 2-7
2.2.5 Site Type (5) - Maximum Ozone
Concentration - Secondary Downwind
Direction 2-8
2.3 PAMS SITE SELECTION 2-8
2.3.1 Spatial Scales 2-8
2.3.2 General Monitoring Area 2-10
2.3.3 Probe Siting and Exposure Criteria . . 2-12
2.3.4 Practical Considerations 2-16
2.3.5 Specific PAMS Sites Selection
Procedure 2-18
2.4 MINIMUM NETWORK REQUIREMENTS 2-27
2.5 TRANSITION PERIOD 2-27
2.6 METEOROLOGICAL PARAMETER MONITORING 2-29
2.7 AIR TOXICS MONITORING 2-33
...
-------
TABLE OF CONTENTS (Continued)
Page
3.0 MONITORING METHODS AND NETWORK OPERATIONS 3-1
3.1 MONITORING METHODS 3-1
3.2 OPERATION SCHEDULE AND SAMPLING FREQUENCY 3-3
4.0 PAMS DATA USES 4-1
4.1 NAAQS ATTAINMENT AND CONTROL
STRATEGY DEVELOPMENT 4-1
4.2 SIP CONTROL STRATEGY EVALUATION 4-2
4.3 EMISSIONS TRACKING 4-3
4.4 AIR QUALITY TRENDS APPRAISALS 4-4
4.5 EXPOSURE ASSESSMENT 4-4
4.6 PAMS SITE TYPE DATA USES 4-5
4.6.1 Site Type (1) 4-5
4.6.2 Site Type (2) 4-6
4.6.3 Site Type (3) 4-7
4.6.4 Site Types (4) and (5) 4-7
5.0 REFERENCES ..... 5-1
APPENDIX A - PAMS DATA APPLICATIONS FOR PHOTOCHEMICAL
GRID MODELING
A.I OVERWHELMING TRANSPORT A-l
A.2 URBAN AREAS INFLUENCING OZONE NONATTAINMENT AREAS . A-2
A. 3 MODEL INPUT A-2
A.3.1 Urban Airshed Model (UAM) A-3
A.3.2 Empirical Kinetic Modeling Approach
(EKMA) A-5
A.3.3 U.S. EPA TRAJECTORY Model A-6
A.4 MODEL EVALUATION PERFORMANCE A-7
A. 5 REFERENCES A-7
tl*.030
IV
-------
LIST OF FIGURES
Page
2-1 PAMS Network Design for an Isolated Area 2-4
2-2 PAMS Network Design for a Multi-Area/Transport
Region (PAMS for Each City A, B, and C Will
Serve Duplicate Functions) 2-5
2-3 Steps for Selecting PAMS Site Locations 2-19
2-4 Approximate Sector Locations for PAMS
Site Types (1) to (5) Based on
Predominant Wind Flow Ul and U2 for an
Isolated Area 2-26
tls.030
-------
LIST OF TABLES
Page
2-1 Ozone Nonattainment Areas for Isolated
and Transport Areas 2-11
2-2 Minimum Separation Distances Between Roadways
and PAMS 2-14
2-3 U.S. 1985 Anthropogenic NO, Emissions 2-21
2-4 U.S. 1985 Anthropogenic NMOC Emissions 2-22
2-5 Minimum Network Requirements 2-28
2-6 Transition Period for PAMS Operations 2-30
3-1 Site Type Measurements Required for Each
Monitoring Objective 3-2
3-2 Ozone Monitoring Season by State 3-4
A-l Boundary Conditions Required in EKMA and UAM A-4
tls.030
VI
-------
-------
LIST OF ABBREVIATIONS AND ACRONYMS
CAAA
CBO
EKMA
CMSA
MSA
NAAQS
NAMS
NMOC
NOX
PAMS
ROM
SIP
SLAMS
UAM
VOC
RFP
Clean Air Act Amendments
Central Business District
Empirical Kinetic Modeling Approach
Consolidated Metropolitan Statistical Area
Metropolitan Statistical Area
National Ambient Air Quality Standards
National Air Monitoring Stations
Non-methane Organic Compounds
Oxides of nitrogen
Photochemical Assessment Monitoring Stations
Regional Oxidant Model
State Implementation Plan
State and Local Air Monitoring Stations
Urban Airshed Model
Volatile Organic Compounds
Reasonable Further Progress
tli.030
vii
-------
-------
1.0 INTRODUCTION
1.1 REGULATORY BACKGROUND AND PURPOSE
Under Title I, Section 182, of the Clean Air Act Amendments
of 1990 (CAAA), the Environmental Protection Agency (EPA) is
proposing a rule to revise the current ambient air quality
surveillance regulations (40 CFR Part 58). The driving forces
behind the proposal are the lack to date of successful attainment
of the ozone air quality standard and the desire to obtain an
improved air quality database for ozone and ozone precursors.
Included in the proposal are provisions for (1) enhanced ambient
air monitoring of ozone and oxides of nitrogen (NO,) ;
(2) monitoring of volatile organic compounds (VOC) (including
aldehydes); and (3) measurement of meteorological parameters.
The proposed rule would require implementing a national
network of enhanced ambient air monitoring stations. States with
metropolitan statistical areas (MSA's) or consolidated
metropolitan statistical areas (CMSA's) classified as serious,
severe, or extreme for ozone nonattainment would be required to
establish photochemical assessment monitoring stations (PAMS) as
part of their State Implementation Plan (SIP).
The general objectives of the PAMS are outlined below.
NAAQS Attainment and Control Strategy Development
Provide an air quality database to help air
pollution control agencies assess ozone attainment
status;
Extend the air quality database for future
attainment demonstrations;
Characterize ozone and precursor transport; and
til.030
-------
Support photochemical model input requirements and
model performance for future attainment
demonstrations and control strategy development.
SIP Control Strategy Evaluation
Evaluate effectiveness of various control
strategies; and
Assist in developing cost-effective VOC and NO,
reductions and control strategies.
Emissions Tracking
Assist in tracking VOC and NOX emission inventory
reductions;
Provide additional information to demonstrate
Reasonable Further Progress (RFP) toward the
attainment of the National Ambient Air Quality
Standard (NAAQS) for ozone; and
Corroborate and assess accuracy of VOC and NOX
emission inventories.
Trends
Prepare long-term ozone, VOC, NOX, and toxic air
pollutant trends; and
. -- Improve effectiveness of the trends database.
Exposure Assessment
Characterize population exposure to ozone and
toxic air pollutants.
The main purposes of this document are to familiarize State
and local air authorities with the enhanced ozone monitoring
program and to recommend network design strategies for the PAMS.
EPA is also preparing a guidance document on PAMS measurement
methods for ozone and ozone precursor compounds entitled
tls.030
1-2
-------
"Technical Assistance Document for Sampling and Analysis of Ozone
Precursors."1 The user is encouraged to refer to this document
for information on manual and automated sampling techniques for
VOC's and non-methane organic compounds (NMOC), and methodologies
for measuring NOZ.
1.2 GENERAL APPROACH
Design criteria for the PAMS network are based on the
selection of an array of data collection sites that satisfy the
monitoring objectives in Appendix D, Section 4, of 40 CFR
Part 58. These sites would allow ambient data on ozone precursor
source areas and predominant wind directions associated with high
ozone events to be developed and made accessible through the
Aerometric Information Retrieval System (AIRS) National database.
Specific monitoring objectives are associated with each site
location or combination of site locations. The PAMS network
design will enable characterization of precursor emission sources
within an MSA/CMSA, transport of ozone and ozone precursors into
and out of an MSA/CMSA, and photochemical processes that result
in ozone exceedances.
Section 2.0 of this document describes the PAMS network
design and includes network requirements, site types, and the
site type selection procedures. Section 3.0 defines monitoring
methods and network operations. Section 4.0 describes how data
from the PAMS will be used. Section 5.0 contains references.
Appendix A contains information on those PAMS data applications
of interest for photochemical grid modeling.
tls.030
-------
2.0 NETWORK DESIGN
2.1 INTRODUCTION
New ozone monitoring sites are required by the CAAA to
enhance the existing ambient air monitoring network currently
composed of State and Local Air Monitoring Stations (SLAMS), the
National Air Monitoring Stations (NAMS), and Special Purpose
Monitors (SPM) stations. These enhanced monitoring sites, called
photochemical assessment monitoring stations (PAMS), will measure
ozone, VOC (including aldehydes), and NO, concentrations, and
meteorological parameters.
The proposed PAMS network array will enable EPA to acquire
data needed for National Ambient Air Quality Standards (NAAQS),
and aid in characterizing precursor emission sources within an
area, evaluating transport of ozone and its precursors into and
out from an area, and understanding photochemical processes
related to ozone nonattainment. The PAMS will also assist in
developing an initial urban air toxic pollutant database.
As the PAMS will become part of the SLAMS network, they will
be subject to specific siting, quality assurance, analytical
methodology, sampling interval, and instrument requirements.
This guidance document provides a description of the PAMS sites,
and the requirements for siting and configuring the sites. A
companion guidance document1 describes the requirements for ozone
precursor data to be gathered and the techniques used to acquire
this data.
The network design information presented in this section is
organized as follows: PAMS site types are described in
Section 2.2. The criteria and procedures for selecting site type
locations are give in Section 2.3. Section 2.4 describes minimum
tl«.030
-------
PAMS network requirements. Guidance for the transition period
during which PAMS will be phased in is presented in Section 2.5
Finally, information on meteorological and air toxics monitoring
is found in Sections 2.6 and 2.7, respectively.
2.2 PAMS SITE TYPES
PAMS site types and general uses of the data from each site
type are described in this section (Section 4.0 describes data
uses in detail). Unlike SLAMS and NAMS, which focus on specific
pollutants, PAMS focus on site requirements. Specific PAMS
monitoring objectives are associated with each site location or
with combinations of site locations. Specific monitoring
objectives and how they relate to precursor emissions, maximum
ozone locations, background air quality, and pollutant
transformation, require five PAMS site types:
Site Type (1) - Upwind background.
Site Type (2) - Downwind edge of maximum precursor
emissions.
Site Type (3) - Downwind fringe of MSA/CMSA.
Site Type (4) - Maximum ozone concentration -
primary downwind direction.
Site Type (5) - Maximum ozone concentration -
secondary downwind direction.
To meet the PAMS monitoring objectives, site distribution
within and in the proximity of MSA's/CMSA's should be based on
design criteria described in this guidance document. The PAMS
design criteria and site locations include considerations of
ozone precursor source areas, ozone "hot-spot" areas, ozone/ozone
tls.030
-------
precursor background areas, and downwind areas prevalent during
high ozone episodes.
Predominant wind direction associated with ozone exceedances
must be determined in order to designate PAMS site types.
Predominant wind direction should be chosen based on several
considerations. Available historical data should be reviewed for
the predominant winds during: (1) the sampling period, (2) ozone
episodes, and (3) the daily ozone formation period. The intent
is to focus on the predominant wind direction during the sampling
period (June-August), when the highest ozone concentrations are
expected to occur. It is recognized that wind directions will
vary between the beginning and the end of a particular sampling
period, and they will also vary between different parts of the
country. Individual areas are encouraged to perform additional
reviews of available meteorological data for shorter periods
(i.e., ozone episodes and/or diurnal variations) as necessary to
ensure effective siting.
PAMS are sited relative to the most predominant wind
direction during the sampling period (Ul) and the second most
predominant wind direction (U2). (Although Ul and U2 are the
first and second most predominant wind directions, other wind
directions may play a role in determining which PAMS will provide
data to meet regulating objectives.) The relative locations of
site types and their relationship to predominant wind flow for a
single urban area are illustrated in Figure 2-1. The relative
locations of site types for multi-area/transport region (or an
urban corridor) are shown in Figure 2-2.
Data uses from the site types (see Section 4.0) will vary,
depending on the predominant wind flow patterns during the ozone
episode under review. Meteorological parameters and monitoring
data must be evaluated together in order to address the
tls.030
2-3
-------
CO
o
<
ca
O)
05
1
CM
03
2-4
-------
3
S
1
i
S«e Type (2) for City B
SHe Type (4) lor City A |
U.
1
1
SNe Type (1
»
.-"''
ffl ;
8\
O
| S«*Ty|M(3)fofCltyA
| Sft*Typ*(1)forCiiyB
^^l^M
<
$
2
*r
*
i
o
2 -
!£ 5 S
a.i
2-5
-------
objectives of the PAMS, regardless of the original siting
criteria and intended use of the data.
The following subsections describe the purpose and general
location of each site type.
2.2.1 Site Type (1) - Upwind Background
The purpose of Type (1) sites is to characterize background
and transported ozone and ozone precursor concentrations entering
the MSA or CMSA. Type (1) sites should be located in the
predominant upwind direction from the local area of maximum
precursor emissions during the sampling period. They should be
located at a distance sufficient to ensure that urban scale
measurements are obtained, as defined elsewhere in this section.
Typically, Type (1) sites will be located 10 to 30 miles from the
city limits or fringe of the urbanized area, in the predominant
upwind direction during the sampling period.
2.2.2 Site Type (21 - Downwind Edge of Maximum Precursor
Emissions
The purpose of Type (2) sites is to determine the magnitude
and type of precursor emissions for areas where highest emissions
are expected. Precursor emissions will be characterized and
apportioned using measurements of different types of ozone
precursors (e.g., volatile hydrocarbons, volatile carbonyl
compounds). Type (2) sites should be located immediately
downwind of the area of maximum precursor emissions during the
sampling period and are typically placed near the downwind
boundary of the central business district (CBD) to ensure that
neighborhood scale measurements are obtained.
The site location should not be unduly influenced by single
emission sources. Site locations immediately downwind of the CBD
tl».030
2~6
-------
are recommended because maximum precursor emissions typically
occur within the CBD. Some urban areas may have very little
industry within the CBD; rather, industrial emissions may be
concentrated along the outer fringe of the CBD or urban core. In
this case, a more suitable Type (2) location may be downwind of
this industrial area.
2.2.3 Site Type (3) - Downwind Edge of MSA
Type (3) sites are established to measure changes in
precursor concentrations downwind of emission sources that are
located within city limits or at the fringe of the urbanized
area. Precursor concentration ratios will also be determined
from these measurements. Type (3) sites should be located in an
intermediate position between the area of maximum precursor
emissions and the downwind area where maximum ozone
concentrations would be expected. These sites are intended to
ensure that neighborhood scale measurements are obtained [between
Sites Types (2) and (4)] (see Section 2.3.1 for further
explanation). Typically, Type (3) sites are located 10 to 20
miles from the CBD or at the fringe of the urbanized area, in the
predominant downwind direction during the sampling period.
2.2.4 Site Type (4) - Maximum Ozone Concentration - Primary
Downwind Direction
Type (4) sites are intended to measure maximum ozone
concentrations resulting from an upwind area of precursor
emissions. These sites should be located directly downwind of
the highest ozone precursor emissions sites [i.e., Type (2)
sites]. Type (4) sites should be located downwind of urban
areas, along the most predominant wind direction during the
sampling period. The location should be chosen so that urban
scale measurements are obtained. Typically, Type (4) sites
should be placed 10 to 30 miles from the urban fringe or the
tls.030
2-7
-------
location of a Site Type (3), in the predominately downwind
direction during the sampling period.
2.2.5 Site Type (5) - Maximum Ozone Concentration - Secondary
Downwind Direction
The purpose of Type (5) sites is similar to that of Type (4)
sites, except that Type (5) sites should be located downwind of
urban areas, along the second most predominant wind direction
during the sampling period. The location of Type (5) sites
should be chosen so that urban scale measurement are obtained.
Typically, Type (5) sites should be placed 10 to 30 miles from
the fringe of the urbanized area or the location of a Site
Type (3) and, as noted, in the second most predominant downwind
direction during the sampling period.
2.3 PAMS SITE SELECTION
Site selection is one of the most important tasks associated
with monitoring network design and must result in the most
representative location to monitor the air guality conditions
being assessed. General recommendations for site selection are
provided in this document. Detailed site selection guidelines
for monitoring ozone and precursor pollutants are given in "Site
Selection for the Monitoring of Photochemical Air Pollutants."2
PAMS site selection will follow the general guidance found in
that reference. It is further recommended that photochemical
models be used to assist in the design of the network.
2.3.1 Spatial Scales
The basis for monitor site selection, according to the
referenced guidelines, is to first match each site-specific
monitoring objective to an appropriate scale of spatial
representation, and to then choose a monitoring location that is
U..030
-------
characteristic of that spatial scale. Five spatial scales are
commonly applied to air pollution monitoring: microscale, middle
scale, neighborhood scale, urban scale, and regional scale. The
spatial scales that are most relevant to the enhanced ozone
monitoring network are the regional, urban, and neighborhood
scales.
The regional scale defines conditions within an area of
reasonably homogeneous geography and extends in distance from
tens to hundreds of kilometers. This scale is most relevant to
Type (1) monitoring sites.
The urban scale characterizes city-wide conditions with
dimensions on the order of 4 to 50 km. Measurements on an
"urban" scale represent concentration distributions over a
metropolitan area. Monitoring on this scale relates to precursor
emission distributions and control strategy plans for an
MSA/CMSA. Site Types (4) and (5) are characteristic of the urban
scale.
The neighborhood scale defines conditions within some
extended areas of the city that have a relatively uniform land
use and range from 0.5 to 4 km. Measurements on a neighborhood
scale represent conditions throughout a homogeneous urban
subregion. Precursor concentrations, on this scale of a few
kilometers, will become well mixed and can be used to assess
exposure impacts and track emissions. Neighborhood data will
provide information on pollutants relative to residential and
local business districts.
VOC sampling sites, including Site Types (2) and (3), are
characteristic of neighborhood scales. Measurements of these
reactants are ideally located just downwind of the edge of the
urban core emission areas. The urban core is defined as "a
clearly defined industrialized area with a high emission
tls.030
2-9
-------
density." Further definition of neighborhood and urban scales
is provided in Appendix D of 40 CFR, Part 58* and "Site
Selection of the Monitoring of Photochemical Air Pollutants."2
2.3.2 General Monitoring Area
After choosing the appropriate spatial scale of
representation, a general monitoring area must be selected that
is characteristic of the required spatial scale and consistent
with the monitoring objectives (micrositing). This is done by
reviewing certain background information, including area land use
patterns, emissions inventories, population densities, traffic
distributions, climatological and meteorological data, and any
existing monitoring data. The use of gridded photochemical
models is especially useful in defining expected areas of steep
low concentration gradients and important source/receptor
relationships. Candidate monitoring sites are then selected from
within the general monitoring area by eliminating from
consideration all locations that might be unduly influenced by
emissions from specific non-representative pollution sources or
by non-representative topography.
Using the previous guidance, a close examination should be
made of the MSA's or CMSA's under review before selecting the
monitor locations. A distinction should be made between MSA's
that are isolated and those that are consolidated into a corridor
of urban areas. The possibility of multi-day transport should be
considered in defining isolated urban areas or corridors of urban
areas. Table 2-1 shows all areas in the United States listed as
serious, severe, or extreme, grouped as Isolated or Transport
areas.
Meteorological factors are used to identify which general
monitoring areas qualify for upwind or downwind PAMS sites. In
Us. 030
2-10
-------
w
s
2
CO
a
o
Ed
O
ca
to
I
w
I
M
§
I
n
w
4
00
'i»-v.
4.
*» ^
1
j»
«/*
1
s
**
1
£
^
1
H
.. H
:$-
::/.
#"
§ § § § § § i
U U l_ k U 1. U
41 41 41 41 41 41 41
«/»(/*«/» i/i «/» *n t/»
§
= * * < < <
2 * x >~ ' u i «
lei ? 5
a at o« « «
*is £8 i 3
Ewe 2 o
£55 S5 5 5
*«
:f
-'
t/i
1
.-.v.;.-.
'-: v/
^
^
1
^
o
SJ
I
. *~
>;;
..::-
jtjt^v J{ 2 0*1 ««0««a«««i
e e
Z ^ ! s
ii § -5^5 .z
M aux T z S n «
u i 3 « . i «. u u.
« e^e 01 K « £ i
> O*l 3« C >- «- W1 V
ee « < u -^ _i 3 t. " at «
la 1 15 ?ls ^slfillli
Issc ll 111 llillgful
-i w> kk, m 5 aa oxtst aeno.Z(noa3a.a.
2-11
-------
general, these areas will be remotely located. The wind
patterns, combined with the length of time required to form
ozone, are important factors in locating the monitors for
measuring both maximum precursor and maximum downwind ozone
concentrations. The idealized network design described in
Section 2.2 is partly based on consideration of meteorological
conditions. Meteorological data measurements from existing sites
or from National Weather Service (NWS) stations can be used to
determine the influence of prevailing wind patterns on major
sources in order to pinpoint optimum monitor locations. If
available, gridded photochemical air quality models should be
utilized to assist in the siting process.
2.3.3 Probe siting and Exposure Criteria
The probe siting and exposure criteria for PAMS monitors are
similar to those for NAMS/SLAMS monitors for such items as the
minimum distance of the inlet probe from obstructions, vertical
and horizontal probe placement, minimum distances from trees, and
spacing from roadways. These criteria are given in the following
subsections. More detailed guidance can be found in "Site
Selection for the Monitoring of Photochemical Air Pollutants,"2
"Quality Assurance Handbook for Air Pollution Measurements,"3
and "Technical Ass.
Ozone Precursors."3
Vertical and Horizontal Probe Placement
To achieve comparability with NAMS/SLAMS ozone monitoring
data, the height of the inlet probe for PAMS monitors should be
as close as possible to the breathing zone, but must be located
3 to 15 meters above ground level. Since PAMS involve multi-
pollutant measurements, this range serves as a practical
compromise for finding suitable probe positions in the siting
2-12
and "Technical Assistance Document for Sampling and Analysis of
,1
-------
area. The probe must also be located more than 1 meter
vertically or horizontally away from any supporting structure.
Since VOC's are not routinely measured as part of NAMS/SLAMS
monitoring programs, additional siting criteria comparable to
those required for PSD monitoring of noncriteria pollutants
should also be applied. These criteria include a minimum
separation distance of 2 meters between the inlet probe and any
walls, parapets, penthouses, etc. for probes located on roofs or
other structures. In addition, probes should be located far from
any furnace or incineration flues.
Spacing from Obstructions
The probe must be located away from obstacles and buildings
such that the distance between any obstacle and the inlet probe
is at least twice the height that the obstacle protrudes above
the sampler. There must be unrestricted airflow in an arc of at
least 270° around the inlet probe, and the predominant and second
most predominant wind direction during the sampling period must
be included in the 270° arc. If the probe is located on the side
of a building, 180° clearance is required.
Spacing from Roads
Motor vehicle emissions constitute a major source of both
ozone precursors and scavenger compounds. It is important,
therefore, to maintain a minimum separation distance between
roadways and PAMS monitoring sites such that the representation
of the resulting monitoring data is not compromised. Table 2-2
gives the required minimum separation distances from roadways for
various traffic volumes. The minimum separation distance must
also be maintained between an PAMS station and other similar
areas of automotive traffic, such as parking lots. Nearby roads
should be far enough away from Site Types (2) and (3) probe
2-13
-------
TABLE 2-2.
MINIMUM SEPARATION DISTANCES
BETWEEN ROADWAYS AND PAMS
Average Daily Traffic
(Vehicles/Day)
Minimum Separation Distance'
(meters)
<10,000
15,000
20,000
40,000
70,000
>110,000
20
30
50
100
>250
'interpolation of these distances should be made for
intermediate traffic data.
tl«.030
2-14
-------
inlets to avoid producing localized ozone sinks. Likewise,
nearby roads should not be located near Site Types (1), (4),
and (5) probe inlets, as precursor pollutants could have a local
influence on these regionally representative sites.
Spacing from Trees
Trees can provide surfaces for adsorption and/or reactions,
and can also affect normal wind flow patterns. To limit these
effects, probe inlets should be placed at least 20 meters from
the dripline of any trees and must certainly be more than
10 meters from the dripline of any trees that are located between
the urban city core area (or other area of maximum ozone
precursors) and the monitoring station along the predominant
sampling period daytime wind direction.
Exposure of Meteorological Instruments
The 10-meter meteorological tower at each PAMS site should
be located such that the resulting measurement data are
representative of the meteorological conditions that affect
pollutant transport and dispersion within the area that the
monitoring site is intended to represent. Meteorological
instruments should be located away from the immediate influence
of trees, buildings, steep slopes, ridges, cliffs, and hollows.
Additional guidance for siting meteorological instruments is
given in the EPA's "Ambient Monitoring Guidelines for Prevention
of Significant Deterioration (PSD),"8 "On-Site Meteorological
Program Guidance for Regulatory Modeling Applications,"7
"Technical Assistance Document for Sampling and Analysis of Ozone
Precursors."
2-15
-------
2.3.4 Practical Considerations
This section highlights practical considerations regarding
the design of PAMS networks, particularly for those States under
budget constraints. Costs are a strong driving force in
selecting and implementing PAMS site types. Multiple uses of the
data from various PAMS site types may result in lower program
implementation costs. However, alternative uses of the data are
subject to review and approval by the Administrator.
Some PAMS objectives have a higher priority than others.
Cost can be minimized by prioritizing objectives as follows:
For Type (1) sites:
1. Maximum background ozone concentration.
2. Model verification.
3. Transport of ozone precursors.
For Type (2) sites:
1. Characterize maximum VOC emissions.
2. Characterize maximum NOZ emissions.
3. Characterize maximum concentration of urban air toxics.
4. Verify model.
5. Characterize population exposure.
For Type (3) sites:
1. Determine VOC/NOX ratios.
2. Speciate VOC's.
3. Determine transport and reactivity of ozone precursors.
4. Verify model.
5. Determine population exposure.
tls.030
2~16
-------
For Type (4) and (5) sites:
1. Determine maximum downwind ozone concentration.
2. Verify model.
3. Determine spatial extent of reactivity through
measurement of VOC.
Although network minimizations have been incorporated into
the PAMS design, States planning to implement the PAMS may find
some of these network design requirements to be impractical
and/or an economic burden. States facing budget limitations may
not be able to obtain suitable data without using existing SLAMS
sites or acquiring additional monitoring data from industry-
sponsored programs.
States may be able to add or improve monitoring capabilities
at existing SLAMS sites or private monitoring sites. An
evaluation should be made of existing monitoring sites to
determine which, if any, would potentially qualify as PAMS. Some
site locations may qualify on the basis of their location in
MSA's/CMSA's. After carefully confirming that these sites are
properly located and will meet PAMS objectives, review and
addition of the appropriate PAMS monitoring techniques should be
performed.
Although private monitoring sites are primarily established
to measure maximum pollutant levels from a specific source, the
site may be suitable, depending on the utilization of the data
retrieved. Two types of private monitors may exist:
1. Monitors designed for preconstruction or post
construction purposes. Most are in operation for
1 year and are primarily intended for background
measurements.
2-17
-------
2. Monitors designed to measure maximum impacts from
sources possibly under permit restrictions. These
sites can be in operation for 6 months to several years
and are intended to reflect air quality concentrations
associated with a single source.
Some preconstruction monitoring sites may have measurement
data for ozone and meteorological parameters. These data have
limitations, however, as sites are sparse and monitors are in
operation for varying time periods.
2.3.5 Specific PAM3 Site Selection Procedure
A summary of the steps for selecting PAMS sites is given in
Figure 2-3. Specific site selection guidance relevant to each
PAMS site type is given in the following subsections. This
guidance is based on the idealized network design that was
described in Section 2.2. In situations where the following
guidance is impractical because of the uniqueness of the source
distribution, land use patterns, or geography, alternative
network designs are allowed by federal regulations. Alternative
network designs, however, must demonstrate that they satisfy the
monitoring data uses and fulfill the overall PAMS objectives
described in Section 1.1.
Note that in some cases, monitoring stations operating as
NAMS or SLAMS may already exist within the general monitoring
area. In these cases, if the site is properly located as a PAMS,
federal regulations require that existing monitoring stations
only be supplemented with the additional instruments necessary to
comply with the PAMS monitoring requirements.
2-18
-------
O
LU
06
O
i
CVJ
£
1
;?,
I
M^H
if
ji-i
M
i ^
1 '"5
I1
1
1
9
\
.s a
a
llf
1
I
a
u
S
II
~ 3
I I
« 5 .2
ill
ii
3 1 !
.2 3 S
S B 2
Ml
li!
2-19
-------
Type (1) Monitoring Sites
The basic objective of Type (1) sites is to characterize
upwind background and transported ozone and ozone precursor
concentrations. Measurements conducted at these sites should be
representative of the regional scale in the direction that is
predominantly upwind from the MSA during conditions that are most
conducive to ozone formation during the sampling period.
To select a Type (1) monitoring site, one must first
determine the predominant wind direction associated with strong
photochemical activity. One must then select the general
monitoring area in the predominant upwind direction from the MSA,
and outside the area of influence of the MSA. Typically,
Type (1) sites should be located approximately 10 to 30 miles
from the city limits or fringe of the urbanized area.
To obtain measurements that are most representative of
background conditions, Type (1) monitoring sites should ideally
be located on a small hill or knoll where the surface destructive
effects of trees and other nearby obstacles on ozone will be
minimal. Type (1) sites should also be sufficiently far from
roads and other major sources of NO, and NMOC emissions so that
the data truly represent the region. The specific monitoring
locations should comply with the probe siting and exposure
criteria given in Section 2.3.3.
«
Minimum separation distance between roadways and PAMS
monitoring locations are discussed in Section 2.3.3. Other types
of NOZ and NMOC's sources that may affect the regional
representation of a monitoring site are shown in Tables 2-3 and
2-48, respectively. These tables indicate total U.S. annual
emissions of NMOC and NOX from various anthropogenic source
categories. More detail regarding emission sources and their
2-20
-------
TABLE 2-3. U.S. 1985 ANTHROPOGENIC NO* EMISSIONS
Soars*-...
Category
Transportation
On- road vehicles'
Off-road vehicles
Subtotal
Stationary fuel combustion
Electric utilities
Other
Subtotal
Sol id waste (Subtotal)
Industrial processes
Chemicals
Metals
Other
Subtotal
Miscellaneous
Unplanned fires
Agricultural activities
Controlled burning
Waste disposal
Organic solvents
Oil and gas production
and marketing
Other
Subtotal
Total
«**..«
Are**-
Sources
OcTrT)
6811.0
2023.3
8834.3
0.0
2022.3
2022.3
69.2
0.0
0.0
0.0
0.0
39.0
0.0
90.4
0.0
0.0
0.0
0.0
123.*
11055.2
X
61.6
18.3
75:9
0.0
18.3
18.3
0.5
0.0
0.0
0.0
O.B
0.4
0.0
o.a
0.0
0.0
0.0
0.0
i.r
100.0
':". Point
Sources
{IcTWT
0.0
0.0
ff.ft
6769.6
1800.8
8570.4
ta.s.
171.7
76.7
371.6
6201ft:
0.0
4.8
0.0
0.0
8.3
289.7
0.0
3or:f
9511.5
X
0.0
0.0
o.a
71.2
18.9
30.1
a.2
1.3
0.8
3.9
8.5
0.0
0.1
0.0
0.0
0.1
3.0
0.0
3.2
100.0
All--
Sources
(wpn
6811.0
2023.3
8834.3
6769.6
3823 . 1
10592.7
87. S
171.7
76.7
371.6
: 620.0
39.0
4.8
90.4
0.0
3.3
239.7
0.0
432.2
20566.7
I
33.1
9.3
42.9
32.9
18.6
51,5
0.4
0.8
0.4
1.8
3.0
0.2
0.0
0.4
0.0
0.0
1.4
0.0
2.0
99.4
'Source of data - Network Design and Site Exposure Criteria for Non-Methane Organic Hydrocarbons-
SYSAPP - 89/138.
"VTPY - Kllotons per year.
2-21
-------
TABLE 2-4. U.S. 1985 ANTHROPOGENIC NMOC EMISSIONS
Sourc*
Category
Transportation
On-road vehicles'
Off-road vehicles
Subtotal
Stationary fuel combustion
Electric utilities
Other
Subtotal
Solid w*at»
Industrial processes
Chemicals
Metals
Other
Subtotal
Miscellaneous
Unplanned fires
Agricultural activities
Controlled burning
Waste disposal
Organic solvents
Oil and gas production
and marketing
Other
Subtotal
Total
NHOC. Emissions'
Are*
Sources
(10* TPY)
5866.6
1421.1
7287.7
0.0
2433.7
24331.7
508. 8
359.0
0.0
0.0
359; 0
205. 9
50.0
348.1
1430.5
4631.3
2353.4
191.9
3211.1
19900.3
f
29.5
7.1
36.6
0.0
12.2
12.2
3.1
1.3
0.0
0.0
1.8
1.0
0.2
1.7
7.2
23.3
11.8
1.0
46.2
99.9
Point
Sources
do' rm
0.0
0.0
0.5
56.9
162.8
219;7
11.1
518.3
77.3
144.7
740;3
0.0
50.5
0.0
0.0
825.2
522.1
0.0
1397.8
2368.9
X
0.0
0.0
0.0
2.4
6.9
9.3
O.S
21.9
3.3
S.I
31.3
0.0
2.1
0.0
0.0
34.8
22.0
0.0
58.9
100. 0
All
Sources
(10' TPY)
5866.6
1421.1
7287.7
56.9
2596.5
2653.4
619.9
877.3
77.3
144.7
1099.3
205.9
100.5
348.1
1430.5
5456.5
2875.5
191.9
10608.9
22269.2
v,
26.3
S.4
32.7
0.3
11.7
12.0
2.3
3.9
0.3
O.S
4.8
0.9
O.S
l.S
5.4
24.5
12.9
o.a
47.5
99 9
'Source of data - Network Design and Site Exposure Criteria for Non-Methane Organic Hydrocarbons-
STSAPP-89/138.
*8ased on M08ILE4 emission factors.
2-22
-------
influences on site selection can be found in "Network Design and
Site Exposure Criteria for Non-Methane Organic Hydrocarbons."
Next to motor vehicles, the largest source types of NMOC's and
NOj, are petrochemical facilities and electric power plants,
respectively. The minimum separation distances between such
sources and Type (1) sites depends primarily on the magnitude of
emissions from the sources and on meteorological factors.
Dispersion modeling should be conducted to evaluate whether or
not any local emission sources have the potential to disturb the
regional representation of a prospective monitoring site.
Type (2) Monitoring Sites
Type (2) sites are established to monitor the impact of
maximum precursor emissions. The sites should be suited for
monitoring urban air toxic pollutants, and should be located near
the predominantly downwind edge of the central business district
or area of maximum precursor emissions from a large industrial
area.
To select the general monitoring area for Type (2) sites,
emissions inventories should be reviewed to identify the area of
greatest emissions density within the MSA. Monitoring should be
conducted near the predominantly downwind edge of this area.
Although Type (2) sites are intended to monitor the impacts
during the sampling period of maximum ozone precursor emissions,
they should be representative of the neighborhood scale and not
be unduly influenced by any single localized emission source. In
some cases, dispersion modeling of source emissions may be
helpful in identifying areas of uniformly high ozone precursor
concentrations. The specific micrositing of Type (2) sites
should comply with the probe siting and exposure criteria given
in Section 2.3.3, and should be sufficiently remote (several
hundreds of meters) from local sources of VOC's, such as gasoline
stations and dry cleaning establishments.
2-23
-------
Type (3) Monitoring sites
Type (3) sites are intended to measure precursor
concentrations sufficiently downwind of the predominant source
area so that the transport and reactivity of precursor compounds
may be assessed. The general monitoring area for Type (3) sites
is less strictly defined than for other PAMS site types. The
principal siting criterion for Type (3) monitoring locations is
that they be located at an intermediate distance between the area
of maximum precursor emissions and the downwind area where,
during the sampling period/ maximum ozone concentrations are
expected to occur [between Type (2) and Type (4) monitoring
sites]. They should also be representative of the neighborhood
scale in an area not characterized by significant precursor
emissions.
Typically, Type (3) sites will be located approximately 10
to 20 miles from the CBD of the MSA or at the fringe of the
urbanized area, in the predominant downwind direction during the
sampling period. The specific monitoring location should not be
impacted by any nearby source of ozone precursors, and should
comply with the specific probe siting and exposure criteria given
in Section 2.3.3.
Type (4) and (5) Monitoring Sites
Type (4) and (5) sites are intended to monitor maximum ozone
concentrations occurring downwind from the area of maximum
precursor emissions in the first and second most frequently
occurring wind directions, respectively, during the sampling
period. These sites should typically be located approximately 10
to 30 miles downwind from the fringe of the urban area or from a
Type (3) site.
tls.030
2-24
-------
Usually, it would not be possible to determine the point of
maximum ozone concentration with confidence without, perhaps, the
aid of complex photochemical modeling. In general, this point
would be outside the region of major NOr emissions, but within
about 30 miles of the fringe of the urbanized area.
To select Type (4) and (5) monitoring sites, one must first
determine the first and second most frequent wind directions
associated with the sampling period. The general monitoring
areas should then be selected from within an angular segment of
approximately 45° centered on the two most important wind
directions and extending from approximately 10 to 30 miles from
the fringe of the urbanized area. The specific monitoring
location should be sufficiently remote from significant emission
sources of nitrogen oxide (NO), particularly roadways, and should
comply with the probe siting and exposure criteria given in
Section 2.3.3. Existing monitoring data would be helpful in
choosing appropriate locations for Type (4) and (5) sites.
There is considerable flexibility in the micrositing of each
PAMS type within a qualifying zone or area. After considering
the previously discussed selection criteria, the recommended zone
areas illustrated in Figure 2-4 should be considered for final
selection of site type location. These zone areas allow
flexibility in selecting sites for each site type. As shown in
Figure 2-4, a zone area is drawn for each site type and is
defined by a 45° sector centered on the predominant wind
directions Ul and U2. The hatched segments within each sector
serve as a guide for locating specific PAMS site types. The
segment range (45°) allows flexibility while keeping the site
locations within the framework of design recommendations. The
narrowest segments are for Site Types (2) and (3) because of
their proximity to urbanized areas. The other Site Types [(1),
(4), and (5)] have a larger range to work with.
2-25
-------
O CO
?
CD "
.ts c
CO ca
SgS
5 S
8 "
O D
'f $
8 o
3 *
- T3
O C
S§
co H
O CO
I
< §
"f TJ
c^ S^
<33 CO
502
O)
iZ
2-26
-------
2.4 MINIMUM NETWORK REQUIREMENTS
A minimum required number and type of PAMS sites and
sampling requirements have been defined for selected population
ranges. The population sizes are associated with an MSA or CMSA.
The MSA/CMSA basis for monitoring network requirements was chosen
because it typically is a good identifier of the most
representative area that encompasses the emissions sources
contributing to ozone nonattainment. Population figures for an
MSA/CMSA can be used as a surrogate in representing MSA/CMSA
emissions density. However, in some cases, nonattainment areas
or counties may be larger than MSA's/CMSA's; therefore, the PAMS
network design should be based on the larger of the MSA/CMSA, the
county, or the nonattainment area. Preferably, network
specifications will be designed on a case-by-case basis and will
consider the interrelated factors of meteorology, source density
and distribution, demographics, and other appropriate factors.
Population figures must reflect the most recent decennial U.S.
census population report. The minimum network requirements for
each population range are identified in Table 2-5.
MSA's or CMSA's may be grouped to geographically cover an
extended urban corridor. One characteristic of an urban corridor
is that its observed ozone exceedances may be largely due to long
range transport of pollutants. Grouped MSA's or CMSA's may
require fewer total PAMS than the same number of MSA's/CMSA's
considered individually (see Figure 2-2) but each MSA/CMSA must
meet the skeleton network requirements shown in Figure 2-2. In
meeting the urban area minimum requirements (see Figure 2-1), an
PAMS may function as more than one site type.
2.5 TRANSITION PERIOD
Guidance is provided in this section on the implementation
priority of each PAMS site so that a smooth transition can be
2-27
-------
TABLE 2-5. MINIMUM NETWORK REQUIREMENTS
Population Range
(MSA/CMSA, County or
Nonattainment Area)*
Less than 500,000
500,000 to 1,000,000
1,000,000 to 2,000,000
More than 2,000,000
Required Site
Type(s)*
(1)
(2)
(1)
(2)
(4)
(1)
(2)
(3)
(4)
(1)
(2)
(3)
(4)
(5)
Minimum
VOC
Sampling
Frequency0
A
A
A
B
A
A
B
C
A
A
B
C
A
A
Minimum
Aldehyde
Sampling
Frequency0
-
D
E
-
E
E
E
E
-
* Whichever is largest.
See Figure 2-1.
Frequency requirements are as follows:
A
B
Eight 3-hour samples every third day and one 24-
hour sample every sixth day during the
monitoring period.
Eight 3-hour samples every day during the
monitoring period and one 24-hour sample every
sixth day year-round.
Eight 3-hour samples every day and one 24-hour
sample every sixth day during the monitoring
period.
Four 6-hour samples every third day during the
monitoring period.
Four 6-hour samples every day during the
monitoring period.
tls.030
2-28
-------
made to a total enhanced ozone monitoring program. The phase-in
order for each PAMS Site 'Type, and the reason for the order are
as follows:
1. Site Type (2) - Provides the most comprehensive data
reflecting ozone precursor emissions and toxic air
pollutants.
2. Site Type (1) - Delineates the effect of incoming
precursor emissions and concentrations of ozone.
3. Site Type (4) - Provides maximum ozone measurements and
total conversion of ozone precursors.
4. Site Type (3) - Depicts the spatial changes in
concentrations of ozone and precursors as the
pollutants travel across an MSA/CMSA.
5. Site Type (5) - Serves a similar purpose as Site
Type (4) in the second most predominant wind direction.
A variable period of time is proposed for phasing in the
operation of all required PAMS. Within 1 year of the effective
date of promulgation of the rule, or designation or
reclassification of an area as serious, severe, or extreme for
ozone nonattainment (whichever is later), a minimum of one
Type (2) site must be operating. Operation of the remaining site
types must, at a minimum, be phased in over the subsequent
4 years, according to the schedule shown in Table 2-6.
2.6 METEOROLOGICAL PARAMETER MONITORING
Upper air and surface meteorological monitoring are
important to the success of the PAMS program. Combined upper air
2-29
-------
TABLE 2-6. TRANSITION PERIOD FOR PAMS OPERATIONS
Years After
Promulgation/
Redesignation
1
2
3
4
5
Minimum Number of
Sites In
Operation
1
2
3
4
5
Operating Site
Types
(by phase- in order)
(2)
(2),(1)
(2) , (1) , (4)
(2),(1),(4),(3)
(2).(1),(4,,(3,.(5)
tl«.030
2-30
-------
and surface meteorological measurements will be used to support
monitoring objectives associated with model inputs and
performance evaluations, assessing source/receptor interactions,
and determine pollutant transport fluxes. In particular,
meteorological data are needed to determine the impact of climate
on the relationship between emission data and air quality
changes.
Meteorological monitoring is required at each PAMS to
diagnose the behavior of photochemical grid models and to trace
emission sources. The meteorological data collected will be most
useful in the development of wind fields for photochemical grid
models. The data will also be used to estimate mixing heights,
vertical wind and temperature structure, and atmospheric
stability. The following requirements should be met in order to
achieve these goals:
Surface meteorological monitoring of wind
speed/direction, temperature, relative humidity,
barometric pressure, and solar radiation should be
measured at sites that measure VOC data.
Operations for collecting meteorological data should be
established coincident with site establishment.
Upper air meteorological monitoring is encouraged at a
representative site in each nonattainment area. Upper
air data should be collected for approximately 10 to
20 key days per year, corresponding to model input
requirements.
Surface meteorological monitoring will be required at each
PAMS. Surface meteorological measurements should begin
coincident with site establishment. Measurements of surface
meteorological data should be acquired at a level of 10 meters
2-31
-------
above ground level for each PAMS site. The 10-meter tower should
be located so that surrounding structures and trees do not have
an immediate influence on measurements. These meteorological
data should reflect the origins of, and the conditions within,
the air mass containing pollutants which the inlet probe will be
sampling. These data should correspond to, or have the
capabilities of converting into, photochemical model input
requirements. For example, wind speed and direction should be
reported over a 1-hour averaging time.
Upper air sites are not required to operate at the same
locations as the surface PAMS sites, although it is preferred
because the meteorological data will be used to reflect the
origins of each pollutant measured and the meteorological
conditions within the air mass advected across the PAMS sites.
Upper air meteorological measurements should be initiated for
areas where existing upper air data are not available. The
location of upper air measurements should be selected in an area
representative of the nonattainment area under review. Upper air
measurements are strongly encouraged, but not required. Upper
air meteorological data should be measured for approximately 10
to 20 key days per year. Model input requirements will dictate
which meteorological parameters need to be derived from the upper
air data.
More specific guidance on meteorological measurements can be
found in "On-Site Meteorological Program Guidance for Regulatory
Modeling Applications,1'7 "Technical Assistance Document for
Sampling and Analysis of Ozone Precursors,"1 and "Quality
Assurance Handbook for Air Pollution Measurement Systems:
Volume IV, Meteorological Measurements."3
tla.030
2-32
-------
2.7 AIR TOXICS MONITORING
Urban air toxics monitoring is required for VOC species and
other hazardous air pollutants under Title III/ Section 301, of
the 1990 CAAA. Measurements of these species could be collocated
with measurements of other pollutants as part of the enhanced
national ozone monitoring network. PAMS Type (2) sites could
serve simultaneously as urban air toxics monitoring sites, as
well as ozone and ozone precursor monitoring sites.
Methods typically used for air toxics measurement are not
addressed in this guidance document (see "Technical Assistance
Document for Sampling and Analysis of Ozone Precursors" ) .
However, manual methods, such as canister sampling for VOC
species, will be used for both quality assurance purposes to
check the continuous VOC measurement data and to provide
estimates of annual means for air toxics assessment purposes.
Air toxics monitoring will include data gathered for
semivolatiles and polar compounds. Other hazardous compounds,
including metals, pesticides, and products of incomplete
combustion (PICS) will be measured, provided resources are
available.
2-33
-------
3.0 MONITORING METHODS AND NETWORK OPERATIONS
3.1 MONITORING METHODS
Table 3-1 summarizes the measurement requirements that
satisfy all PAMS monitoring objectives. To maintain
comparability with measurements being obtained as part of
NAMS/SLAMS monitoring networks, all PAMS measurements of ozone
and NO, should be conducted using automated, EPA designated
reference or equivalent methods. No such reference methods exist
for meteorological parameters or VOC's. However, as certain
minimum uniform criteria concerning these measurements need to be
maintained, selection of monitoring methods for these parameters
should be performed in accordance with guidance documents such as
"Technical Assistance Document for Sampling and Analysis of Ozone
Precursors"1 and "Quality Assurance Handbook for Air Pollution
Measurement Systems: Volume IV. Meteorological Measurements."5
States are required to use these documents in selecting and
conducting measurements at PAMS. Consecutive hourly average
measurements of ambient concentrations of both criteria and non-
criteria pollutants are required. Because this sampling
frequency is higher than typical for manual canister programs,
automated VOC monitoring is highly recommended.
Alternative methods for conducting VOC measurements may be
allowed by EPA, however, they must be described in detail in the
network description and subjected to public comment and approval
by the EPA Administrator.
Special care must be taken in monitoring VOC's at SLAMS
designated as PAMS. FEP Teflon is unacceptable as the probe
material because of VOC adsorption and desorption reactions on
the FEP Teflon. Borosilicate glass, stainless steel, or their
equivalent are the acceptable probe materials for VOC and
tls.030
-------
I
E
I
CD
I
1
tu
B
X
CC
B
I
Uj
5
i
\
\
ili
to.
n
S-S
II
ill
ii!
III
3-2
-------
aldehyde sampling. Care must be taken to ensure that the sample
residence time is minimized.
3.2 OPERATING SCHEDULE AND SAMPLING FREQUENCY
To maintain comparability with NAMS/SLAMS networks, uniform
monitoring frequencies have been established. The operating
schedule for continuous measurements being conducted as part of
PAMS (i.e., ozone, NOX, and VOC's, using automated gas
chromatography) is the same as that required by federal
regulations for SLAMS continuous analyzers. This schedule
requires collection of consecutive hourly averages except during
periods of routine maintenance, instrument calibration, and
periods or seasons exempted by the Regional Administrator.
Typically, PAMS monitoring will be conducted annually at
least throughout the months of June, July, and August, when peak
ozone concentrations are expected to occur. A longer monitoring
period is preferred for sites that have extended ozone seasons.
With regard to SLAMS monitoring, the ozone monitoring season
varies on a State by State basis, typically extending from April
through October. It is preferable, although generally not
required, that PAMS monitoring be conducted during the entire
ozone monitoring period for the area. Table 3-2 gives the ozone
monitoring season for each state in the United States. VOC
sampling done in conjunction with PAMS monitoring is planned for
June, July, and August at a minimum to coincide with peak ozone
periods.
Manual ozone precursor and aldehyde sample collection should
be conducted during the same operating period as PAMS ozone and
NOX measurements. Other VOC sampling f(3r toxics, however, should
be for any 3-month period during the year. The required
frequency and duration of each sampling period for manual methods
tls.030
3-3
-------
TABLE 3-2. OZONE MONITORING SEASON BY STATE
State
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
District of Columbia
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Puerto Rico
Rhode Island
South Carolina
South Dakota
Tennessee
Texas AQCR 4.5.7.10.11
Texas AQCR 1,2.3.6,8.9.12
Utah
Vermont
Virginia
Washi ngton
West Virginia
Wisconsin
Wyoming
American Samoa
Guam
Virgin Islands
Begin Month
March
April
January
March
January
March
April
April
April
January
March
January
April
April
April
April
April
April
January
April
April
April
April
April
March
April
June
April
January
April
April
January
April
April
May
April
March
April
April
January
April
April
June
April
January
March
May
April
April
April
April
April
April
January
January
January
End Month
November
October
December
November
December
September
October
October
October
December
November
December
October
October
October
October
October
October
December
October
October
October
October
October
November
October
September
October
December
October
October
December
October
October
September
October
November
October
October
December
October
October
September
October
December
October
September
October
October
October
October
October
October
December
December
December
'40 CFR 58, Appendix 0
tla.030
3-4
-------
depends on the PAMS site type and population of the MSA.
Measurements are typically conducted over 24-hour periods;
however", in many cases, it is required that the 24-hour period be
comprised of either four separate 6-hour sample or eight separate
3-hour samples. Table 2-4 (Section 2.4) presents the minimum
sampling frequency requirements for PAMS manual methods sampling.
3.3 ANALYSES
The analyses required of discreet samples for ozone
precursors and aldehydes are discussed in a separate technical
assistance document entitled "Technical Assistance Document for
Sampling and Analysis of Ozone Precursors" (EPA Contract No. 68-
DO-0125, Work Assignment 22, October, 1991). This technical
assistance document should be consulted for the descriptions and
considerations of the monitoring methodologies, including
analyses.
tls.030
3-5
-------
4.0 PAMS DATA USES
Dat^a from the PAMS network will serve several purposes,
including evaluation of attainment of the National Ambient Air
Quality Standards (NAAQS), SIP control strategy development and
evaluation, corroboration of emissions tracking, preparation of
trends appraisals, and population exposure assessment. Each of
these data uses is described in more detail in this section.
Measurement requirements by site type for PAMS objectives are
summarized in Table 3-1 (Section 3.1). Potential application of
PAMS data to various ambient modeling applications (e.g., UAM,
ROM, EKMA, TRAJECTORY) is provided in Appendix A.
4.1 NAAQS ATTAINMENT AND CONTROL STRATEGY DEVELOPMENT
The data from PAMS, combined with data from existing SLAMS
and NAMS monitors, will be used to monitor ozone exceedances and
provide input for attainment/nonattainment decisions. In
addition, PAMS data will help resolve the roles of transported
and locally emitted ozone precursors in producing observed
exceedances and may be used to identify specific sources
contributing to observed exceedances and excessive concentrations
of ozone precursors.
PAMS data will also assist in characterizing the
concentrations of ozone and ozone precursors occurring on days
when high ozone levels are measured, thereby extending the
database available for future attainment demonstrations. These
demonstrations will be based on photochemical grid modeling and
other approved analytical methods and will provide a basis for
prospective mid-course control strategy corrections. PAMS data
will provide (1) information concerning which areas and episodes
to model in order to develop appropriate control strategies;
(2) boundary conditions required by the models to produce
quantifiable estimates of needed emissions reductions; and (3) a
tl».030
4-1
-------
means to evaluate the predictive capability of the models used.
PAMS data are not designed to be the sole source of air quality
data for input and evaluation of photochemical grid models.
Site Types (4) and (5), which measure ozone and, in some
cases, VOC and NOX concentrations downwind of the affected MSA or
CMSA, will be used for ozone attainment demonstrations and
control strategy development.
4.2 SIP CONTROL STRATEGY EVALUATION
Long-term PAMS data will be used to evaluate the
effectiveness of SIP control strategies. Data from PAMS sites
can validate the impact of emission reductions on air quality
levels for ozone if retrieved at the end of a time period during
which control measures were implemented. Additionally, ambient
monitoring data from PAMS will be used to determine diurnal
patterns of VOC emissions.
Speciation of measured VOC data will allow determination of
which organic species are most affected by emissions reductions
and assist in developing cost-effective, selective VOC reduction
control strategies. All VOC species have different reactivities;
therefore, the influence of control measures on specific species
may have a bearing on the degree of ozone reductions achieved. A
State or local air pollution control agency may use this
information in developing strategies for its particular
nonattainment area that are best suited for that area and can
achieve the greatest emissions reductions at the least cost.
Site Types (2) and (3), which measure VOC and NOX air
quality concentrations, will be used to measure and document
changes in ozone precursor emissions in order to evaluate control
strategy effectiveness.
tl«.030
4-2
-------
4.3 EMISSIONS TRACKING
Development of emission inventories for VOC's, NO^, and CO
in ozone nonattainment areas is required as part of the
1990 CAAA. PAMS data will be used to corroborate the quality of
VOC and NOX emission inventories. Although a perfect
mathematical relationship between emission inventories and
ambient measurements does not yet exist, a qualitative assessment
in terms of the relative distribution of various compounds in the
ambient air could be roughly compared to current emission
inventory estimates to judge the accuracy of the emission
inventories. The importance of collecting ambient data to verify
emission inventory estimates has been shown through comparative
studies involving predictive methods and measured data.
PAMS data will allow tracking of VOC and NOZ emission
reductions and corroborate emissions trends analyses. VOC and
NOZ emission inventory reductions for baseline emissions are
required as part of the CAAA-mandated Reasonable Further Progress
(RFP) demonstrations. While the regulatory assessment of
progress will be made in terms of emission inventory estimates,
the ambient data can provide independent trends analyses and
corroboration of these assessments. The ambient assessments,
using speciated data, can provide insight into whether the
estimated emission improvements are supported by ambient
measurements.
Speciated data can also be used to assess the adequacy of
assumptions used for speciated emissions input during
photochemical grid modeling exercises and to identify urban air
toxic pollutant problems that deserve closer scrutiny. The
speciated VOC data will be used to determine changes in the
species profile resulting from the emission control program,
particularly those resulting from fuel reformulation.
tls.030
4-3
-------
PAMS data from Site Types (2) and (3) will be used to
corroborate and assess the accuracy of VOC and NOX emission
inventories. Long-term PAMS data from Site Types (2) and (3)
will be used to track VOC and NOX emission reductions and support
RFP demonstrations.
4.4 AIR QUALITY TRENDS APPRAISALS
Long-term PAMS data will be used to establish VOC, NO, NO2,
NO,, and toxic air pollutant trends, and supplement the ozone
trends database. Multiple statistical indicators will be
tracked, including ozone and its precursors on the 10 days during
each year with the highest ozone concentration, the seasonal
means for these pollutants, and the annual means at
representative locations.
Surface meteorological parameters monitoring at each PAMS
will help maximize the utility of these trends analyses by
comparisons with meteorological trends and transport influences.
The meteorological data will also help interpret ambient air
pollution trends. In terms of overall ozone level increases or
decreases nationwide, historical data have shown that
meteorological conditions can play a major role in determining
contributing factors to ozone level trends.
Long-term PAMS data from Site Types (2) and (3) will be used
to establish VOC and NOX trends, and data from all site types
will be used to supplement existing ozone trends databases.
4.5 EXPOSURE ASSESSMENT
PAMS data will be used to better characterize exposure of
populations living in serious, severe, or extreme ozone
nonattainment areas to ozone and toxic air pollutants. Because
tls.030
4-4
-------
ozone and its precursors are by-products of numerous large and
small stationary sources and motor vehicle emissions, the
distribution and magnitude of ozone and ozone precursor
concentrations within MSA's/CMSA's needs to be determined,
utilizing as many monitors as possible. Knowledge of the spatial
distribution of measured levels of these pollutants, in relation
to demographics, will help determine ozone pollutant levels to
which populations are typically exposed. Annual mean toxic air
pollutant concentrations will be calculated to determine the risk
to the population associated with individual VOC species in urban
environments.
Site Types (2) and (3), located in populated areas, are
suitable for this purpose. Ozone, VOC's, and NOX would be
measured at these sites. Urban air toxics information would be
most meaningful from Site Type (2) locations.
4.6 PAMS SITE TYPE DATA USES
Specific monitoring objectives associated with each PAMS
site location are described below.
4.6.1 Site Type (1)
Type (1) sites will characterize upwind background and
transported ozone and its precursor concentrations entering an
area and will identify those areas that are subjected to
overwhelming transport. Data collected from Type (1) sites will
be used to:
develop and evaluate future control strategies;
identify incoming emissions;
tls.030
45
-------
establish boundary conditions for future photochemical
grid modeling and mid-course control strategy changes;
determine NAAQS attainment for ozone and NO2/* and
analyze pollutant trends.
4.6.2 Site Type (2)
Type (2) sites will monitor the magnitude and type of
precursor emissions in the area where maximum emissions are
expected, and they are ideally suited for monitoring urban air
toxic pollutants. Data collected from Type (2) sites will be
used to:
develop and evaluate future control strategies;
corroborate NOX and VOC emission inventories;
augment RFP tracking;
verify photochemical grid model performance;
characterize ozone and toxic air pollutant exposures
(maximum site for toxic emissions impact);
analyze pollutant trends, particularly toxic air
pollutants and annual ambient VOC trends to compare
with trends in annual VOC emission estimates; and
determine NAAQS attainment for ozone and NO2.
tit.030 M
4-6
-------
4.6.3 Site Type (3)
Type (3) sites will monitor changes in precursor
concentrations and ratios downwind of the emissions sources.
Data collected from Type (3) sites will be used to:
determine NAAQS attainment for ozone and NC>2 (this site
type may coincide with an existing maximum NO2 NAMS
monitoring site) ;
measure transport and reactivity of precursors;
verify photochemical grid model performance;
characterize ozone exposures; and
analyze pollutant trends.
4.6.4 Site Types Ml and
Types (4) and (5) sites will monitor maximum ozone
concentrations occurring downwind from the area of maximum
precursor emissions in the first and second most frequently
occurring wind directions, respectively. Data collected from
Type (4) and (5) sites will be used to:
determine NAAQS attainment for ozone and NO2 (this site
type may coincide with an existing maximum
concentration ozone or a population exposure NC>2 NAMS
monitoring site) ;
establish boundary conditions for photochemical grid
modeling;
develop and evaluate future control strategies; and
tls.030
4-7
-------
analyze pollutant trends, particularly for VOC and
ozone.
U..030
-------
5.0 REFERENCES
1. Technical Assistance Document for Sampling and Analysis of
Ozone Precursors. Atmospheric Research and Exposure
Assessment Laboratory, U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina. Draft, June 1991.
2. Site Selection for the Monitoring of Photochemical Air
Pollutants. Office of Air Quality Planning and Standards,
U.S. Environmental Protection Agency, Research Triangle
Park, North Carolina. EPA-450/3-78-013. 1978.
3. Anthropogenic Emissions Data for the 1985 NAPAP Inventory.
Prepared for the National Acid Precipitation Assessment
Program by the U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina. EPA-600/7-88-022.
1988.
4. Network Design for State and Local Air Monitoring Stations
(SLAMS) and National Air Monitoring Stations(NAMS). Code of
Federal Regulations, Title 40, Part 58, Appendix D. July
1, 1990, ed.
5. Quality Assurance Handbook for Air Pollution Measurement
Systems: Volume IV. Meteorological Measurements.
Environmental Monitoring Systems Laboratory, U.S.
Environmental Protection Agency, Research Triangle Park,
North Carolina. EPA-600/4-82-060. February 1983.
6. Ambient Monitoring Guidelines for Prevention of Significant
Deterioration (PSD). Office of Air Quality Planning and
Standards. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. May 1987
7. On-Site Meteorological Program Guidance for Regulatory
Modeling Applications, U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina. EPA-450/4-87-013.
1986.
8. L.A. Mahoney, R.S. MacArthur, SAI. Network Design and Site
Exposure Criteria for Nonmethane Organic Hydrocarbons.
Office of Air Quality Planning and Standards. U.S.
Environmental Protection Agency, Research Triangle Park,
North Carolina. SYSAPP-89/138. November 1989.
9. L.A. Mahoney, R.S. MacArthur, SAI. Network Design and Site
Exposure Criteria for Nonmethane Organic Hydrocarbons.
Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park,
North Carolina. SYSAPP-89/138. November 1989. (unreleased)
tl».030
-------
APPENDIX A
PAMS DATA APPLICATIONS FOR PHOTOCHEMICAL GRID MODELING
-------
-------
APPENDIX A
PAMS DATA APPLICATIONS FOR PHOTOCHEMICAL GRID MODELING
This section provides a detailed description of applications
of each Site Type in terms of monitoring objectives pertaining to
photochemical grid modeling.
A.I OVERWHELMING TRANSPORT
Enhanced ozone monitoring data will be used to characterize
transported ozone and its precursor concentrations entering
MSA's/CMSA's and will identify those nonattainment areas that are
subject to overwhelming transport.1
Exceedance episodes may be discounted based on overwhelming
transport (contribution of local emissions to an observed
exceedance is relatively minor). If overwhelming transport is a
factor, an analysis of culpable upwind sources areas has to be
made. The analysis would include the use of an urban scale
photochemical model supported by monitoring information
representing regional scale transport of ozone and precursors
into the urban area under evaluation.
For a given MSA/CMSA under review, the following monitoring
site types will be required to help verify that transported ozone
and ozone precursors are of sufficient levels to be responsible
for ozone violations in the downwind nonattainment areas. The
upwind Site Type (1) would be used to measure O3. A Type (2)
site located near the fringe of the CBD, would be used to measure
VOC and NOX. Measurement data obtained to verify overwhelming
transport should be from Sites Types (1) and (2) located near
culpable MSA/CMSA upwind of the nonattainment area where the
ozone exceedances occur.
tla.030
A-l
-------
A.2 URBAN AREAS INFLUENCING OZONE NONATTAINMENT AREAS
Enhanced ozone monitoring data will be used to provide input
to, and verification of, future photochemical grid modeling
analyses. Emission reductions needed to achieve the national
ambient air quality standard (NAAQS) for ozone must be evaluated
for urban areas contributing to ozone exceedances. Source areas
responsible for contributing to ozone exceedances are primarily
found within urbanized areas. Photochemical air quality models
.provide the most practical means of determining needed reductions
of VOC and/or NOZ emissions. For serious, severe, and extreme
nonattainment areas, photochemical grid models are required to
demonstrate the effectiveness of control measures in achieving
the NAAQS for ozone. The Urban Airshed Model (UAM)2'3 is
recommended for this purpose. The modeled area or domain will
have to be large enough to include the contributing urban
sources, available air quality monitoring sites, and the
nonattainment area under review.1'* Data from the PAMS will
provide needed information for model input and will assist in
model performance evaluations.
A.3 MODEL INPUT
This section provides a description of the input
requirements for photochemical grid modeling. Meteorological and
air quality monitoring data provide multiple uses: (1) scoping
modeling domains and episodes, (2) inputs needed to drive the
models, and (3) evaluating the predictive capabilities of
selected models.
Input to the urban scale models can be provided through
regional scale modeling results or ambient measurements.
Regional scale modeling results will be generated through the
application of the Regional Oxidant Model (ROM).1'3 Ambient
tls.030
A-2
-------
measurements of ozone and ozone precursor concentrations and
meteorological parameters could also be obtained from PAMS. PAMS
data, particularly from Site Types (1) and (4), could prove
useful in assessing and enhancing the ROM-derived boundary
conditions.
A UAM designed preprocessor program and a diagnostic wind
field model using measurements from the PAMS will provide
appropriate inputs to the urban modeling analysis. Surface
measurements of ozone, NMOC, NOX, and CO can be used for
characterizing initial and boundary conditions for UAM.
A.3.1 Urban Airshed Model (UAM)
Enhanced ozone monitoring data will assist in providing
inputs for urban scale models such as UAM. Ambient measurements
are used for developing initial and boundary conditions, and
gridded fields of meteorological parameters. The boundary
conditions required during the application of UAM are shown in
Table A-l1. Air quality data will include measurements of ozone
and ozone precursor concentrations. Meteorological data will
include measured wind speed and direction, temperature, humidity,
atmospheric pressure, and solar radiation.
Because UAM uses a three-dimensional grid, there are
practical limitations to collecting monitored data for individual
boundary grid cells. PAMS data will be useful for developing
boundary conditions; however, in most cases, only one PAMS site
will be available.
Site Types (l), (4), and (5) located in areas outside of the
MSA/CMSA under review are the most appropriate PAMS for providing
boundary conditions.1 Based on predominant meteorological
conditions (Ul), Type (1) is the most preferable site for
tla.030
A-3
-------
TABLE A-l. BOUNDARY CONDITIONS REQUIRED IN EKMA AND UAM
POLLUTANT
NMOC:
Carbon Bond
IV
Speciation
1) PAR
2) ETH
3) OLE
4) ALD2
5) FORM
6) TOL
7) XYL
8) ISOP
9) MEOH
10) ETOH
03
N02
NO
CO
SOURCE
ENOMS*
(I)/ (4) ,(5)
(I)/ (4), (5)
(I)/ (4) ,(5)
<1),(4),(5)
SOURCE
DEFAULTS
30 ppbc
Carbon
Fraction
0.498
0.034
0.020
0.037
0.070
0.042
0.026
0.000
0.273
0.000
40 ppb
2 ppb
0 ppb
350 ppbb
METEOROLOGICAL
PARAMETERS
(Hourly) :
Wind Speed
Wind Direction
Temperature
Humidity
Atmospheric
Pressure
Solar
Radiation
SOURCE
ENOMS*
1-5
*ENOMS Site Type.
bSource: PEPE/NEROS Study,
tla.030
A-4
-------
characterizing boundary conditions. Site Type (5) is the second
most preferable site based on the second most predominant
meteorological conditions. Data from Site Type (4) may
supplement those from Site (1) in establishing boundary values.
Application of Site Types (1), (4), and (5) for these purposes is
acceptable, provided the data from each site are regional in
scale. Boundary conditions based on VOC monitoring data should
be obtained from Site Types (1) and (4) using 3-hour values taken
every 3 to 6 days. These sites should be situated outside of the
MSA/CMSA under review. It should be understood that these are
general recommendations and that case-specific analyses using UAM
modeling to assist in monitor placement is advised.
All site types can provide data to characterize gridded
initial conditions. Some site types, such as Types (2) and (3)
situated within the urban modeling domain, will be particularly
useful for formulating initial conditions. Meteorological
parameters obtained from all site types will assist in the
development of gridded wind fields, as well as other gridded
meteorological data fields.
Monitoring needs for evaluating the performance of UAM
include measurements of ozone and ozone precursor concentrations
at selected urban scale sites. Potentially, most, if not all,
sites may be useful data sources for assessing model performance.
A.3.2 Empirical Kinetic Modeling Approach (EKMA)
Enhanced ozone monitoring data will assist in providing
inputs for urban scale models such as city-specific EKMA.5 Air
quality measurements are needed to specify initial conditions,
and meteorological measurements are needed to estimate mixing
heights, reaction rates, and atmospheric moisture content. Air
quality data will include measurements of ozone and ozone
precursor concentrations. Meteorological data will include
tls.030
A-5
-------
measured wind speed and direction, temperature, humidity,
atmospheric pressure, and solar radiation representative of the
urban area.
The boundary conditions required during the application of
EKMA are shown in Table A-l.
Use of upwind surface air quality monitors meeting PAMS
siting criteria is recommended for estimating present boundary
conditions for EKMA. Site Types (1), (4), and (5) are
recommended for estimating present boundary conditions for ozone,
NO, and NO2. Complete monitoring needs for determining boundary
conditions for EKMA include measurements of ozone, VOC, NOX, and
CO. Boundary condition values for VOC may be estimated from a
single 3-hour sample taken between 6 and 9 LCT every 3 to 6 days.
A.3.3 U.S. EPA TRAJECTORY Model
This model computes a trajectory using surface wind data
from National Weather Service stations and other suitable
monitoring sites to assist in locating culpable MSA's/CMSA's
upwind of nonattainment areas. The model is intended to
characterize mesoscale winds. Hourly daytime (8:00 am - 8:00 pm)
data are needed as input to the model. The TRAJECTORY model6 is
not applicable to nighttime meteorological conditions, as surface
wind data at night are not always representative of winds aloft.
It is desirable to use as many wind observations as possible to
construct these trajectories. PAMS will serve to provide
additional surface wind speed and direction data.
Surface meteorological data will be obtained from all site
types for upwind regions where back trajectories are calculated.
These data will help supplement existing surface meteorological
data within the upwind region. Upper air meteorological data
tls.030
A-6
-------
associated with the enhanced ozone monitoring program, along with
the surface meteorological data will be used in verifying the
back trajectory calculations.
A.4 MODEL PERFORMANCE EVALUATION
PAMS will provide more adequate data for evaluating the
performance of UAH. The EPA guidelines for using UAM recommend a
model performance evaluation in conjunction with attainment
demonstrations. This performance evaluation will determine how
well the model characterizes processes involved in case-specific
ozone exceedances. The PAMS will provide data useful for
conducting model performance assessments. As performance
evaluations of ROM will be based on extensive areas covering ROM
modeling domains, the PAMS network design should be such that an
adequate spatial distribution of regional ambient measurements
can be obtained for this purpose.
Surface ozone and upper air wind measurements are useful
supplementary data for TRAJECTORY. Time sequences of observed
ozone data, upwind along the path of the trajectory, can be used
to evaluate TRAJECTORY'S hypothesis.
Upper air wind measurements can be used to test whether the
model has made appropriate adjustments to surface wind
observations used as input to the model. These adjustments are
intended to make hourly wind data more representative of the wind
flow throughout the mixed layer. Surface and upper air ambient
measurements from PAMS will provide data for evaluation purposes.
A.5 REFERENCES
1. Criteria for Assessing the Role of Transported
Ozone/Precursors in Ozone Non-Attainment Areas. Office of
Air Quality Planning and Standards. U.S. Environmental
A-7
-------
Protection Agnecy, Research Triangle Park, North Carolina.
EPA-450/4-91-015. May 1991.
2. User's Guide for the Urban Airshed Model: Volume V.
Description and Operation of the ROM-UAM Interface Program
System. Office of Air Quality Planning and Standards. U.S.
Environmental Protection Agency, Research Triangle Park,
North Carolina. June 1990.
3. User's Guide for the Urban Airshed Model. Volume I: User's
manual for UAM (CB-IV). Office of Air Quality Planning and
Standards. U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina. June 1990.
4. Guidelines for Regulatory Application of the Urban Airshed
Model. Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle Park,
North Carolina. Draft, March 1991.
5. Procedures for Applying City-Specific EKMA. Office of Air
Quality Planning and Standards, U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina.
EPA-450/4-89-012. July 1989.
6. Meyer, E.L. and K.A. Baugues. Consideration of Transported
Ozone and Precursors and Their Usage in EKMA. Office of Air
Quality Planning and Standards, U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina.
EPA-450/4-89-010. July 1989.
A-8
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
REPORT NO.
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE Enhanced Ozone Monitoring Network
)esign and Siting Criteria Guideline Document
5. REPORT DATE
July 1991
6. PERFORMING ORGANIZATION CODE
. AUTHOR(S)
:adian Corporation "
:esearch Triangle Park, N.C. 27609
8. PERFORMING ORGANIZATION REPORT NO.
. PERFORMING ORGANIZATION NAME AND ADDRESS
. S. Environmental Protection Agency
.esearch Triangle Park, N.C. 27711
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68D00125
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
New__ozone monitoring sites are required by the CAAA to enhance the existing
ambient air monitoring network currently composed of State and Local Air Monitoring
Stations (SLAMS), the National Air Monitoring Stations (NAMS), and Special Purpose
Monitors (SPM) stations. These enhanced monitoring sites, called photochemical
assessment monitoring stations (PAMS), will measure ozone, VOC (including aldehydes),
and NO concentrations, and meteorological parameters. As the PAMS will become
part or the SLAMS network, they will be subject to specific siting, quality
assurance, analytical methodology, sampling interval, and instrument requirements.
This guidance document provides a description of the PAMS sites, and the requirements
for siting and configuring the sites.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
Siting Guideline
Photo Chemical Assessment Monitoring
Stations (PAMS)
Network Oesiign
18. DISTRIBUTION STATEMENT
Jnlimited
19. SECURITY CLASS (ThisReport!
Unclassified
21. NO. OF PAGES
66
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (Rev. 4-77) PREVIOUS EDITION is OBSOLETE
-------
------- |