# C l a r k C o u n t y D e p a r t m e n t o f A i r Q u a l i t y & E n v i r o n m e n t a l M a n a g e m e n t

A n n u a l N e t w o r k P l a n R e p o r t J u n e 2 0 1 0ii June 15, 2010
Jared Blumenfeld, Regional Administrator U.S. Environmental Protection Agency, Region 9 75 Hawthorne Street San Francisco, CA 94105

RE: ANNUAL NETWORK PLAN

Dear Mr. Blumenfeld:
The Clark County Department of Air Quality and Environmental Management (DAQEM) has completed the “Annual Network Plan Report” requi red by Title 40, Part 58 of the Code of Federal Regulations. The plan has been availabl e for public inspection since April 15, 2010, on our Web site at http://www.accessclarkcounty.com/dep ts/daqem/aq/Pages/aq_index.aspx . In addition, a newspaper announcement was published, th e plan was availabl e at the DAQEM front counter for review, and recipients were notified electronically fr om a list of environmental contacts.
This report addresses the followi ng objectives, set forth in guidance from the U.S. Environmental Protection Agency:

1. Ambient Air Quality Monitoring Methodology. 2. Network Design. 3. Probe and Path Siting Criteria. 4. Quality Assurance Requirement. 5. Periodic Systems Audits and National Performance Audits. 6. Corrective Action.

DAQEM will continue to evaluate the monitoring network for program effectiveness in the following areas: effectively meeting users’ needs, effectively siting monitors , appropriate scale of representation, meeting air m onitoring objectives, monitoring National Ambient Air Quality Standards, determining the effectiveness of ai r pollution control programs, and informing the public of air pollution levels.
If you have any questions related to this repo rt, please contact Yousaf Hameed, Air Quality Monitoring Supervisor, at (702) 379-4465.
Respectfully,

Mike Sword, P.E., CEM DAQEM Engineering Manageriii cc: Meredith Kurpius, Acting Manager, EPA Region 9 Matthew Lakin, EPA Region 9 Joseph Lapka, EPA Region 9 Michael Flagg, EPA Region 9 Mathew Plate, EPA Region 9 Roy Ford, EPA Region 9 Grant Office Lewis Wallenmeyer, Director, DAQEM Tina Gingras, Assist ant Director, DAQEM Yousaf Hameed, Monitoring Supervisor, DAQEMiv Executive Summary

This annual plan reports the status of the Clar k County Department of Air Quality and Environmental Management (DAQEM) air monitoring netw ork. Reporting standards are outlined in Title 40, Part 58 of the Code of Fe deral Regulations (40 CFR 58).
The plan focuses on monitoring network change s that occurred in 2009, planned changes andimprovements in 2010, efforts to improve data quality, and ways in which the information recorded by the network is disseminated.
The 2009 network review identified potential defici encies at two monitori ng stations, along with options for correction. Shortcomings fell into the following categories:

1. Spacing to roadways. 2. Obstacle distance.
DAQEM is continuing efforts to achieve total network compliance with the requirements outlined in 40 CFR 58. The section “S iting Criteria Deficiencies” c ontains an implementation schedule for corrective actions.
In addition to network plan requirements, the U.S. Environmental Protection Agency released the revised final National Ambient Air Quality Standard for NO 2 on February 9, 2010. This plan includes a discussion of the regul ation changes that affect Clar k County and its compliance status.
This plan is an official request for the Region 9 office to determine that this plan meets all applicable requirements of 40 CFR Part 58.v Table of Contents

Table of Contents ............................................................................................................. ............... v List of Figures ............................................................................................................... ................. vi Introduction .................................................................................................................. ................... 1 Public Inspection Process ..................................................................................................... .......... 4 Network Review Methodology .................................................................................................... ... 5 Metropolitan Sta tistical Area ................................................................................................. ......... 6 Climatological Information .................................................................................................... ......... 7 Ambient Air Quality Monitoring Methodology ........................................................................... 10 Siting Criteria Deficiencies .................................................................................................. ......... 15 Design Values for 2009 ........................................................................................................ ........ 16 Site and Instrument Information ............................................................................................... .... 17 Monitoring Start Dates in AQS.................................................................................................. ... 20 Monitoring Site Traffi c Count Summary ...................................................................................... 22 Probe and Path Siting for 2009 ................................................................................................ ..... 23 Carbon Monoxide Monitoring Locations ..................................................................................... 51 Ozone Monitoring Locations .................................................................................................... .... 52 Nitrogen Oxide Monitoring Locations .......................................................................................... 55 Continuous PM 10 Monitoring Locations ....................................................................................... 56 Continuous PM 2.5 Monitoring Locations ...................................................................................... 59 Filter-Based PM 2.5 Monitoring Locations ..................................................................................... 61 Effect of New Regulations on Air Monitoring ............................................................................. 63 Summary of Monitori ng Requirements ........................................................................................ 64 Quality Assurance Program ..................................................................................................... ..... 67 National Performance Audits ................................................................................................... ..... 70 Network Modifications Completed in 2009 ................................................................................. 71 Network Modifications Proposed ................................................................................................ . 72 Status of Monitoring Site Leases .............................................................................................. .... 76 Air Quality System Database Information .................................................................................... 78 Receptor-Measured Criteria Pollutant Trends .............................................................................. 80 Pollen Network ................................................................................................................ ............. 88vi List of Figures

Figure 1 – Topographic Map .................................................................................................... .......9 Figure 2 – Apex ............................................................................................................... ..............24 Figure 3 – Boulder City ....................................................................................................... ..........26 Figure 4 – East Craig Road .................................................................................................... ........27 Figure 5 – East Sahara ........................................................................................................ ...........29 Figure 6 – Green Valley ....................................................................................................... ..........31 Figure 7 – J.D. Smith ......................................................................................................... ............33 Figure 8 – Jean ............................................................................................................... ................35 Figure 9 – Joe Neal ........................................................................................................... .............37 Figure 10 – Lone Mountain ..................................................................................................... ......38 Figure 11 – Mesquite .......................................................................................................... ...........39 Figure 12 – Orr................................................................................................................ ...............41 Figure 13 – Palo Verde ........................................................................................................ ..........43 Figure 14 – Paul Meyer......................................................................................................... .........45 Figure 16 – Sunrise Acres ..................................................................................................... .........46 Figure 17 – Walter Johnson .................................................................................................... .......48 Figure 18 – Winterwood ........................................................................................................ ........49 Figure 19 – Visibility Sites .................................................................................................. ..........50 Figure 20 – Carbon Monoxide Monitoring Locations ...................................................................51 Figure 21 – Ozone Monitoring Locations in Las Vegas, Boulder City, and Apex ........................52 Figure 22 – Ozone Monitoring Location in Jean ...........................................................................53 Figure 23 – Ozone Monitoring Location in Mesquite ...................................................................54 Figure 24 – Nitrogen Oxide Monitoring Locations in Las Vegas .................................................55 Figure 25 – Continuous PM 10 Monitoring Locations in Las Vegas, Boulder City, and Apex ......56 Figure 26 – Continuous PM 10 Monitoring Location in Jean ..........................................................57 Figure 27 – Continuous PM 10 Monitoring Location in Mesquite ..................................................58 Figure 28 – Continuous PM 2.5 Monitoring Locations in Las Vegas and Apex .............................59 Figure 29 – Continuous PM 2.5 Monitoring Location in Jean .........................................................60 Figure 30 – Filter-Based PM 2.5 Monitoring Locations in Las Vegas ............................................61 Figure 31 – Filter Based PM 2.5 Monitoring Location in Jean ........................................................62 Figure 32 – Carbon Monoxide Trends ...........................................................................................8 0 Figure 33 – Ozone Trends ...................................................................................................... ........81 Figure 34 – SO 2 Trends..................................................................................................................82 Figure 35 – NO 2 Trends .................................................................................................................83 Figure 36 – Continuous PM 10 Trends ............................................................................................84 Figure 37 – Filter-Based PM 2.5 FRM Trends .................................................................................85 Figure 38 – Continuous PM 2.5 Annual Mean Trends .....................................................................86 Figure 39 – Continuous vs. Filter-Based PM 2.5 Trends .................................................................87 Figure 40 – Pollen Sampling Locations in Las Vegas, Boulder City, and Apex ...........................89vii 

### Acronyms and Abbreviations

Acronyms
AQS Air Quality System ARM Approved Regional Method BAM Beta Attenuation Monitor CFR Code of Federal Regulations DAQEM Clark County Department of Air Quality & Environmental Management EPA U.S. Environmental Protection Agency FEM Federal Equivalent Method FRM Federal Reference Method NAAQS National Ambient Air Quality Standard NAMS National Air Monitoring Station NCore National Core Monitoring Network PEP Performance Evaluation Program QA Quality Assurance QC Quality Control QCAS Quality Control and Assurance System RAAS Reference Ambient Air Sampler SASS Speciation Air Sampling System SLAMS State and Local Air Monitoring System TTP Through The Probe URG University Research Glassware

Abbreviations

CO carbon monoxide m/s meters per second mb millibar mph miles per hour NO 2 nitrogen dioxide NO x nitrogen oxide O 3 ozone Pb lead PM 2.5 particulate matter 2.5 microns or less in aerodynamic diameter PM 10 particulate matter 10 microns or less in aerodynamic diameter ppm parts per million SO 2 sulfur dioxide1 Introduction

This document is a review of the Clark County Department of Air Quality and Environmental Management (DAQEM) air monitoring network, and serves as a monitoring network plan for future activities. It contains the following elements:

1. Description of the climate of Clark County, Nevada. 2. Documentation of ambient air quality monitoring methodology. 3. Description of monitoring instruments in the network and general station information. 4. Definition of the degree to which the network meets monitoring objectives. 5. Description of probe and path siting compliance. 6. Demonstration that each site monitoring part iculate matter less than 2.5 microns in aerodynamic diameter (PM 2.5 ) meets design value standards. 7. Identification of ozone (O 3 ) monitoring sites that exceed the 2009 ozone design value standard. 8. Review of the Quality Assurance (QA) Program. 9. Confirmation that the agency operates the number of monitors required by Title 40, Part 58 of the Code of Federal Regulations (40 CFR 58). 10. Description of network cha nges during calendar year 2009. 11. Identification of projected network ch anges during calendar year 2010 and beyond. 12. Description of the plan to correct guidance conflicts.
During 2009, the following conditions existed:

1. DAQEM operated air quality instruments to m easure ambient concentrations of the following criteria pollutants: PM 2.5, PM 10 , ozone, carbon monoxide (CO), and nitrogen oxides (NO, NO 2 , NO x ). 2. DAQEM monitored visibility as a special project. 3. DAQEM counted pollen as a special project. 4. DAQEM operated with the following program objectives:

a. Ensure the network is monitoring repres entative data, and geographical and population factors are considered in managing the network. b. Make monitoring data readily accessible to the U.S. Environmental Protection Agency (EPA), regional and national air qualit y agencies, the general public, and stakeholders.

c. Monitor visibility in the Las Vega s Valley using long path technology. d. Review analyzer placement for ozone bounda ries, considering formation and transport.

e. Improve forecasting methods for ozone, PM 10 , and PM 2.5 . f. Make efforts to update monitoring equipment when needed. g. Revise QCAS standard oper ating procedures (SOPs). h. Prepare National Core Monitoring Netw ork (NCore) site for deployment. 5. Clark County remained designated a serious nonattainment area for two criteria pollutants in Hydrographic Area 212, PM 10 and CO. Clark County is in a nonattainment area for O 3 and is awaiting an official EPA cla ssification, which is expected in 2011.2  PM 10 : Clark County has demonstrated complia nce with the NAAQS from the end of 2006 through 2009, and is presumed to be in attainment. There was one exceedance in 2007 (not flagged, not deemed questionabl e data) and two in 2008 (flagged, may be deemed questionable data).

 PM 2.5 : Clark County is presumed to be in attainment of the NAAQS from 2004 through 2009. DAQEM is continuing to assess PM 2.5 Federal Reference Method (FRM) data to confirm. Currently, Clark County is designated as unclassifiable for PM 2.5 . Hydrographic Areas 212, 216, and 164A are desi gnated attainment for PM 2.5 ; all other parts of the county are designated unclassi fiable for this pollutant.

 CO: DAQEM has submitted a maintenance plan fo r CO. EPA's target date for approval is the end of June 2010, at which time Hydrogr aphic Area 212 will be redesignated to attainment for CO. Clark County is requesting redesignation because it has been in attainment of the CO NAAQS since 2000.

 Clark County was designated nonattainm ent for the 1997 ozone NAAQS (85 ppb) in April 2004. However, based on 2006-2009 monitori ng data, Clark Count y is in attainment of the 1997 NAAQS. DAQE M is preparing a maintenan ce plan and redesignation request for the 1997 NAAQS; submittal to EPA is expected in late 2010. EPA reconsidered the 2008 NAAQS (75 ppb) in Septem ber 2009 and proposed a new primary and secondary standard in January 2010. The fina l rule will be promulgated on August 10, 2010.3 Below is a picture of the Air Quality Monitori ng and QA Team. From left to right: Kris Simonian, Air Quality Monitoring Technician II; Prav in Pema, Air Quality Monitoring Technician II; Joe Biebrich, Air Quality Monitoring Technician II; Monte Symmonds, Senior Air Quality Monitoring Technician; Yousaf Hameed, Air Qualit y Monitoring Supervisor; David Dickens, Air Quality Monitoring Technician II; Matt Nelson, Air Quality Monitoring Technician II; Mickey Turner, Senior Air Quality Monitoring Technician; Phil Wiker, Senior Air Quality Monitoring Technician; and Mickey Palmer, Senior Air Qu ality Monitoring Technician and QA Officer.4 Public Inspection Process

This annual monitoring network plan report was published for public inspection 30 days prior to Clark County Board of County Commission approval and subsequent submittal to EPA, in compliance with 40 CFR 58.10. The plan was publis hed and distributed on the DAQEM Web site, made available at the DAQEM fron t counter, advertised in the ne wspaper, and distributed to a list of environmental stakeholders. Public comments on this report may be sent to:

Yousaf Hameed Air Quality Monitoring Supervisor Clark County DAQEM 500 South Grand Central Parkway P.O. Box 555210 Las Vegas, Nevada 891555 Network Review Methodology

This annual monitoring network plan report was written, and the monitoring network was planned, according to “SLAMS / NAMS / PAMS Network Review Guidance,” published in 1998 by the EPA Office of Air Quality Planning and Standards (EPA-454/R-98-003). The report team included supervisors, field technicians, data management specialists, planning staff, quality assurance technician s, and managers.
The team completed the following tasks in preparing this network plan:

1. Evaluated each station for pathway a nd probe siting criteria compliance. 2. Reviewed Air Quality System (AQS) reports. 3. Reviewed topographical maps. 4. Reviewed historical trends in the monitoring network. 5. Reviewed National Weather Service climate resources. 6. Studied traffic count reports prepared by th e Nevada Department of Transportation. 7. Reviewed lease agreements. 8. Calculated design values for ozone and PM 2.5 .6 Metropolitan Statistical Area

Clark County qualifies as one Me tropolitan Statistical Area ( 40 CFR 81). The Las Vegas Valley contains the majority of the population for Clark County; smaller communities, such as Mesquite and Boulder City, do not qualify as Metropolitan Statistical Areas.7 Climatological Information

Information within this section was taken from the National Weather Serv ice, Las Vegas climate book.

1. Topography and History
Las Vegas is located in a broad desert valley in southern Neva da. Mountains surrounding the valley extend 2,000 to 10,000 feet above the valley floor. The Las Vegas Valley comprises about 600 square miles and runs from northwest to so utheast. It is bounded on the north by the Sheep Range, while Boulder City and the Lake Mead National Recreation Area are generally considered its southern extent. To the west are th e Spring Mountains, which include Mt. Charleston, the region's highest peak at 11,918 feet. Several sm aller ranges line the east ern rim of the valley, including the Muddy Mountains, the Black Mountain s, and the Eldorado Range. For most of the Las Vegas metropolitan area, the valley floor slopes downward from west to east. This affects local climatology by driving variations in wind, precipitation, and storm runoff.

Official weather observati ons have been recorded in Las Ve gas since 1937, initially at Nellis Field in the northeast part of the valley. In late 1948, the U. S. Weather Bureau moved to McCarran Field (now McCarran Internat ional Airport), seven miles south of downtown Las Vegas.

2. General Climatic Summary
The four seasons are actually well defined in La s Vegas, although they diffe r from the traditional view of seasonal variation. Summ ers display classic desert Sout hwest characteristics: daily high temperatures typically exceed 100  F, with lows in the 70s. The summer heat is tempered somewhat by the extremely low relative humidity; ho wever, humidity can increase markedly for several weeks each summer in asso ciation with a moist "monsoonal fl ow" from the south, typically during July and August. These moist winds suppor t the development of spectacular desert thunderstorms associated with significant fl ash flooding and/or st rong downburst winds.

Winters, overall, are mild and pleasant. Afternoon temperatures average near 60  F and skies are mostly clear. Pacific storms occasionally produce rain fall in Las Vegas, but in general, the Sierra Nevada Mountains of eastern Ca lifornia and the Spring Mountains immediately west of the Las Vegas Valley act as effective barriers to moisture.
Snow accumulation is rare in Las Vegas. Flurri es are observed once or twice during most winters, but snowfall of an inch or more occurs onl y once every four to five years. However, freezing temperatures occur regularly each year: the va lley has a 30-year average of 24 days with low temperatures at or below 32  . Snowfall is common in the mountains surrounding Las Vegas, with the Spring Mountains receiving between 5 and 10 feet annually. The spring and fall seasons are generally considered ideal. Although sharp temperature change s can occur, outdoor activities are seldom hampered.
Strong winds are the most persis tent weather hazard in the area. Winds over 50 miles per hour (mph) are infrequent, but can occur with vigorous storms. Winter and spring wind events often8 generate widespread areas of blowing dust a nd sand. Strong wind episodes in the summertime are usually connected with thunderstorms, and ar e thus isolated and localized. Prevailing wind direction is typically ei ther southwest or north unless associat ed with a thunderstorm outflow.
Regional transport and local influences produce higher ozone concentrations on the west and northwest sides of the valley. Ozone episodes in the Las Vegas Valley ar e generally characterized by a surface (thermal) low pressure system extending over Arizona, southern California, and Nevada; ridging of 500 millibars (mb) over the southwest or central United States; and southwesterly surface flow during the afternoon hours, accompanied by ample sunshine and high temperatures. Superimposed on the synoptic-scale meteorological conditions are the local, terrain-induced mesoscale meteorological features. Together, these determine the horizontal and vertical advection and dispersi on of pollutants and their eventual removal from the Las Vegas Valley.

3. Synoptic Meteorology
Based on a National Meteorological Center modeli ng analysis at 500 mb, a broad, flat ridge of pressure over the central U.S. is dominant during the summer seas on. Winds at this level, as indicated by the Mercury/Desert Rock Weather Service Meteorological Observatory radiosonde, are normally westerly and characterized by modera te (10-15 m/s) wind speeds. The center’s surface analyses indicate that southern Nevada is enveloped by a thermal low-pressure system.9 Figure 1 – Topographic Map10 Ambient Air Quality Monitoring Methodology

DAQEM’s Monitoring Section operated 16 monito ring stations in Clark County during 2009. The types of monitors vary from station to sta tion. The network primarily consists of State and Local Air Monitoring Stations (SLAMS), with a neighborhood-scale focu s intended to assess exposure levels of the general population. The netw ork also characterizes pollution transport and background levels. It contai ns subnetworks for the EPA criteria pollutants PM 10 , PM 2.5 , CO, O 3 , and NO 2 .

Continuous Particulate Matter Monitors
The sampling methodology employs the continuous Thermo Electr on FH 62 C14 series monitor, which uses carbon-14 as the beta source. All continuous PM 2.5 monitors have a Very Sharp Cut Cyclone as their second stage separator.
Particulate Matter of 10 Microns or Less
During 2009, 13 continuous PM 10 monitors operated in Clark County. Nine operated within the Las Vegas Valley; the Jean, Boulder City, Ape x, and Mesquite monitors operated outside the valley. The maps in the s ection titled “Continuous PM 10 Monitoring Locations” show the locations of the monitors in the PM 10 monitoring network (Figures 25-27).
A quality control (QC) flow rate verifi cation is conducted on the continuous PM 10 monitors every two weeks, exceeding the EPA requirement of once per month. A QA flow rate audit is conducted on the monitors once every six months.
The following table shows the spatial sc ale and monitoring objective for each PM 10 monitor.

Site Spatial Scale Objective Green Valley Middle Population exposure Mesquite Middle Population exposure Palo Verde Middle Population exposure Jean Regional Background Apex Regional Source Craig Road Neighborhood Highest concentration All others Neighborhood Population exposure
Particulate Matter of 2.5 Microns or Less
In 2009, DAQEM operated six continuous PM 2.5 monitors in Clark County. The maps in the section titled “Continuous PM 2.5 Monitoring Locations” show the lo cations of the monitors in the continuous PM 2.5 monitoring network (Figures 28 and 29).11 In accordance with 40 CFR 58.30, DAQEM has determined that all PM 2.5 monitoring sites are representative of area-wide c oncentrations and not directly impacted by unique sources. The Apex Monitoring Station may be an exception due to the close proximity of emission sources.

A QC flow rate verification is conducted on the continuous PM 2.5 monitors every two weeks, exceeding EPA requirements. A QA flow rate audit is conducted on the monitors once every six months.
The following table shows the spatial sc ale and monitoring objective for each PM 2.5 monitor.

Site Spatial Scale Objective Craig Road Neighborhood Population exposure J.D. Smith Neighborhood Population exposure Sunrise Acres Neighborhood Highest concentration Green Valley Middle Population exposure Jean Regional General/background Apex Regional Source-oriented
Filter-Based Particulate Matter Samplers

The PM 2.5 FRM and the PM 2.5 Speciation samplers, the latter of which includes the University Research Glassware (URG) carbon channel sampler, are the only filter-based monitoring instruments DAQEM employs. The maps in the section titled “Filter-Based PM 2.5 Monitoring Locations” show the locations of the samplers in the PM 2.5 FRM monitoring network (Figures 30 and 31). Sampling methodology employs the filter-bas ed FRM Andersen Model 300 Reference Ambient Air Sampler (RAAS).
DAQEM operates a gravimetric laboratory that weighs PM 2.5 FRM filters.
Particulate Matter of 2.5 Microns or Less

In 2009, three filter-based PM 2.5 FRM samplers operated as listed in the table below.

Site Schedule Sunrise Acres One in three days Sunrise Acres (collocated) One in six days Jean One in three days J.D. Smith One in three days

A QC flow rate verification is conducted on the filter-based PM 2.5 FRM samplers once a month; a QA flow rate audit is conducted on the samplers once every six months.
The following table shows the spatial scale and monitoring objective for each routine filter-based PM 2.5 FRM sampler.12 Site Spatial Scale Objective Jean Regional Background Sunrise Acres Neighborhood Highest concentration J.D. Smith Neighborhood Population exposure

In accordance with 40 CFR 58.10, DAQEM will notify the public if a PM 2.5 monitor violates the NAAQS, or if a community monito ring zone (as defined in the Federal Register ) is created or changed. DAQEM will use a two-part process, similar to the current network plan public inspection process, to provide notification of a propos ed monitoring zone cha nge: (1) post to its Web site a review of the PM 2.5 monitoring network with the change s being considered, and (2) solicit feedback from the community. DAQEM will res pond to any public comments and take all comments into consideration before making changes to the PM 2.5 monitoring network. The only exceptions to this process will be a lost lease or a 30-day notice from the property owner to vacate the site.

40 CFR 58.30 describes certain types of microscale PM 2.5 sites as unsuitable for comparison to the annual NAAQS. DAQEM does not operate a microscale PM 2.5 site, so all its FRM PM 2.5 monitors are suitable fo r NAAQS comparisons.
Speciation
DAQEM operates a speciation sampler in conjunc tion with a carbon channel sampler at the East Craig Road site (32-003-0022). U nder an EPA contract, the Resear ch Triangle Institute analyzes speciation samples and reports the results to the AQS.

Carbon Monoxide
The map in the section titled “Carbon Monoxide Monitoring Locations” shows the locations of the monitors in the CO monito ring network (Figure 20). DAQEM uses API 300 Series monitors with gas filter correlation.
DAQEM conducts a three-point QC check on the CO monitors every week and calibrates them quarterly. Twenty-five percent of the CO monito rs undergo a QA audit every quarter, and all CO monitors undergo an audit at least once each year.
The following table shows the spatial scale a nd monitoring objective fo r each CO monitor.

Site Spatial Scale Objective Sunrise Acres Neighborhood Highest concentration All others Neighborhood Population exposure

Ozone
In 2009, DAQEM operated 13 ozone monitors in Cl ark County. Nine operated within the Las Vegas Valley; the Jean, Apex, Boul der City, and Mesquite monitors operated outside the valley. The maps in the section titled “Ozone Monitoring Locations” show the locations of monitors in13 the ozone monitoring network (Figures 21-23). Cl ark County uses API 400 Series ultraviolet absorption monitors.
The majority of the ozone network in Clark County was designed for the one-hour ozone standard. That is now used to calculate eight-hour (rolling average) values for comparison to the current ozone NAAQS.
DAQEM’s ozone projects include:

 “Ozone Characterization Study.”

 “Clark County Regional Oz one & Precursor Study.”

 “Southwest Desert Las Vega s Ozone Transport Study.”

 Biogenic emissions inventory.

 Emission inventory of volatile organi c compounds from consumer products.

 Establishment of upper air wind measurements in Clark County.

 Characterization of 2009 wildfire imp acts on air quality in Clark County.
DAQEM is planning another wildfire study in the summer of 2010 to evaluate how smoke plumes affect Clark County with respect to oz one precursors and ozone formation. The goal is to further characterize smoke plume impacts on ozon e concentrations by showing a quantifiable relationship between ozone, PM 2.5 , and levoglucosan, a chemical marker for wildfires. DAQEM anticipates these wildfire studies will contri bute to successful exceptional event demonstration packages. In addition, there is ev idence that introducing smoke into the analytical bench of ozone analyzers can cause an artificial positive bias. Th us far DAQEM has not b een able to establish this relationship, but it will continue to i nvestigate. DAQEM may deploy a chemiluminescence ozone analyzer in the 2010 study, since it uses a measurement prin ciple that is not affected by particulate interference. All inst rumentation deployed as part of the wildfire study will be operated as special purpose monitoring (SPM).
DAQEM conducts a three-point QC check on the oz one monitors every week and calibrates them quarterly. Twenty-five per cent of the ozone monitors un dergo a QA audit every quarter, and all ozone monitors undergo an audit at least once each year.
The following table shows the spatial scale and monitoring objective for each monitor.

Site Spatial Scale Objective Apex Regional Regional transport Joe Neal Neighborhood Highest concentration Jean Regional Regional transport All others Neighborhood Population exposure
Nitrogen Oxides
In 2009, DAQEM operated two nitrogen oxide mon itors in Clark County. All nitrogen oxide monitors were operated within the Las Vegas Valley. The map in the section titled “Nitrogen14 Oxide Monitoring Locations” shows the locations of monitors in the nitrogen oxide monitoring network (Figure 24). DAQEM uses API 200 Series monitors with gas phase chemiluminescence.
DAQEM conducts a three-point QC check on the nitr ogen oxide monitors every week and calibrates them quarterly. Twenty-five percent of the nitrogen oxide monitors undergo a QA audit every quarter, and all nitrogen oxide monitors undergo an audit at least once each year.
The table below shows the spatial scale a nd monitoring objective for each monitor.

Site Spatial Scale Objective J.D. Smith Neighborhood Highest concentration Joe Neal Neighborhood Population exposure15 Siting Criteria Deficiencies

DAQEM identified the following deficiencies in the 2009 review of the network.

Site Roadway Obstacle Distance E. Sahara CO Walter Johnson Water cooling tower 15’ from inlet

The table below shows the schedule to corr ect the identified siting deficiencies.

Deficiency Site/Monito r Corrective Action Schedule
Spacing from roads E. Sahara/CO Move to Jerome Ma ck Middle School 2010

Obstacle distance Walter Johnson/O 3 DAQEM will monitor data for impacts from cooling tower 2010

Spacing from roads: DAQEM will evaluate spacing and attempt to comply with 40 CFR 58, Appendix E. DAQEM will consider one or more of the following options:

1. Relocate the site. 2. Shut down the site.

Obstacle distance: DAQEM will evaluate the obstacle distance proble m and will attempt to comply with 40 CFR 58, Appendix E. DAQEM will consider the following options:

1. Increase the height of the probe so the obstacle is no longer an issue. 2. Relocate the site. 3. Shut down the site.16 Design Values for 2009

The following table compares ozone desi gn values with the NAAQS standard.

Station Ozone Design Value (ppm) NAAQS Standard (ppm) E. Craig Road 0.072 .075 Winterwood 0.072 .075 Apex 0.074 .075 Lone Mountain 0.076 .075 Palo Verde 0.075 .075 Jean 0.076 .075 Paul Meyer 0.077 .075 Boulder City 0.072 .075 J.D. Smith 0.073 .075 Walter Johnson 0.078 .075 Joe Neal 0.078 .075 Mesquite .0.065 .075 Orr 0.074 .075 Note: ppm = parts per million.
The following table compares annual PM 2.5 design values with the NAAQS standard.

Station PM 2.5 Design Value (  g/m3) NAAQS Standard (  g/m3) Sunrise Acres 9.4 15 Jean 4.1 15 J.D. Smith 8.5 15
The following table compares 24-hour PM 2.5 design values with the NAAQS standard.

Station PM 2.5 Design Value (  g/m3) NAAQS Standard (  g/m3) Sunrise Acres 21 35 Jean 11 35 J.D. Smith 18 35

40 CFR 58.30 describes certain types of microscale PM 2.5 sites as unsuitable for comparison to the annual NAAQS. DAQEM does not operate a microscale PM 2.5 site, so all its FRM PM 2.5 monitors are suitable fo r NAAQS comparisons.17 Site and Instrument Information

Site Information

Apex (32-003-0022). The site is located in Apex Valley, approximately 25 miles northeast of Las Vegas. Its primary purpose is to monitor ambient impacts of emissions from nearby gravel processing and power plants, and pollutant flow out of the Las Vegas Valley. This monitoring site is generally downwind from Las Vegas and serv es as an indicator of pollutant transport flow out of the Las Vegas Valley; this site is the only DAQEM monitoring stati on in the Apex Valley.
Boulder City (32-003-0601). The site is located in Boulder City, approximately 25 miles southeast of Las Vegas. It was estab lished at the request of Boulder City government officials and residents. The primary pollutants of interest are O 3 and PM 10 . Craig Road (32-003-0020). The site is located in the city of North Las Vegas. It was established to comply with permit conditions relate d to potentially high emissions of O 3 precursors. Although that emission source no longer exis ts, the site continues to monitor O 3 , PM 10 , and PM 2.5 ; it periodically violates the PM 10 24-hour standard. Because of other DAQEM efforts and the periodic PM 10 exceedances, the speciation sampler was m oved to this site in March 2007 from the Sunrise Acres site. This s ite has not experienced a PM 10 exceedance since May 2008.

Green Valley (32-003-0298). The site is located in Henderson. It was established because of citizen complaints about dust emissions from a grav el processing plant, a nd continues to monitor PM 10 and PM 2.5 . J.D. Smith (32-003-2000). The site is located in the City of North Las Vegas. It replaced the old McDaniel and Post Office PM sites. The site monitors gaseous (NO x , CO, and O 3 ) and particulate (PM 10 and PM 2.5 ) pollutants using both filter-based and continuous methodologies.

Jean (32-003-1019). The site is located in Jean, approxima tely 30 miles south of Las Vegas. Its primary purpose is to monitor transport pollutants from southern California: O 3 , PM 10 , and continuous and filter-based PM 2.5 . Joe Neal (32-003-0075). The site is located in the northwestpart of Las Vegas. Its primary objective is to monitor O 3 , although a NO x monitor has also been opera ting at this location since January 2008. The topography is such that the summertime loft brings higher O 3 and precursorlevels toward this site from the east end of the Las Vegas Valley. The primary reason for this installation was to monitor O 3 precursors in a high O 3 concentration area, and to support DAQEM modeling efforts. PM 10 was initially deployed at this site du e to population growth in this part of the valley; this site continues to serve its intended population.

Lone Mountain (32-003-0072) . The site is located in the northw est part of Las Vegas. Its primary objective is to monitor O 3 . The topography is such that the summertime loft brings higher O 3 and precursor levels toward this site from the east end of the Las Vegas Valley. DAQEM initiated PM 10 monitoring here because of gravel processing to the west/northwest of the monitoring site.18 East Sahara (32-003-0539). The site, centrally located in the Las Vegas Valley, is one of the oldest sites. Its primary objective is to monitor CO.

Mesquite (32-003-0023). The site is located in Mesquite, approximately 70 miles north of Las Vegas; it monitors O 3 and PM 10 . This station is located along a transport and exit corridor for jurisdictional boundaries.

Orr (32-003-1021). The site is the replacement for the East Flamingo site, which was terminated because the lease was lost and it was too cl ose to the road to meet its original O 3 monitoring objective. DAQEM began monitoring O 3 at Orr in April 2006, and continues monitoring CO and PM 10 there.

Paul Meyer (32-003-0043). The site is located in the southwes t part of Las Vegas. Its primary objective is to monitor O 3 . The topography is such that the summertime loft brings higher O 3 and precursor levels toward this site from the east end of the Las Vegas Valley. PM 10 is also monitored at this location.

Palo Verde (32-003-0073). The site is located in the west pa rt of Las Vegas. Its primary objective is to monitor O 3 . The topography is such that the summertime loft brings higher O 3 and precursor levels toward this site from the east e nd of the Las Vegas Valley. The site also monitors PM 10 . Sunrise Acres (32-003-0561). The site is near the center of the Las Vegas Valley. Monitoring began here as part of a CO study in the 1990s, an d its primary objective is still to monitor CO. After the lease for the East Charleston site was lost, all monitoring activities at that site were transferred to Sunrise Acres. This s ite monitors particulate pollutants (PM 10 and PM 2.5 ) using both filter-based and continuous methodol ogies. The site also utilizes PM 2.5 FRM samplers as the primary and collocated sampling site.

Walter Johnson (32-003-0071). The site is located on the west si de of Las Vegas. Its primary objective is to monitor O 3 . The topography is such that the summertime loft brings high O 3 and precursor levels towards this site from the east end of the Las Vegas Valley.

Winterwood (32-003-0538). The site is located on the east side of Las Vegas, and is one of the oldest sites. Its primary objective is to monitor CO and O 3 . None of the DAQEM monitoring sites are loca ted near furnaces or incinerators.19 Instrument Information

Items monitored: 1. CO 2. O 3 3. NO x 4. PM 10 continuous 5. PM 2.5 continuous 6. PM 2.5 FRM, manual method 7. PM 2.5 species, manual method 8. Visibility 9. Meteorological parameters
Monitor type: 1. CO: gas filter correlation ( non-dispersive infrared). 2. O 3 : ultraviolet absorption. 3. NO x : chemiluminescent gas phase reaction of NO x and O 3 . 4. PM 10 and PM 2.5 C-14 continuous monitor: Beta Attenuation Monitor (BAM). 5. PM 2.5 RAAS manual method: filter-based. 6. PM 2.5 Speciation Air Sampling System (SASS) and URG manual met hods: filter-based. 7. Visibility: transmissometer.

The table below shows DAQEM fulfillment of FR M and NAAQS instrumentation requirements.

Pollutant Instrument FRM FEM SPM Comparable to NAAQS CO API 300 Series X Yes O 3 API 400 Series X Yes NO 2 API 200 Series X Yes SO 2 Monitor Lab ML9850 X Yes PM 10 Thermo Electron C14 X Yes PM 2.5 Thermo Electron C14 X No PM 2.5 Thermo Andersen RAAS X Yes Note: FRM = Federal Reference Method; FEM = Federal Equivalence Method; SPM = Special Purpose Monitor.
Most DAQEM air monitoring stations are equipped with a 10-meter mete orological tower that has an ultrasonic wind speed and wind direction se nsor and an ambient temperature sensor at 10 meters. Some meteorological monitoring stations also have relative hum idity, precipitation, and solar radiation sensors.20 Monitoring Start Dates in AQS

The table below shows monito ring start dates in AQS.

Site Name Site ID Parameter Description A QS Paramete r Code POC Date Sampling Began Apex 0022 Nitrogen dioxide 42602 1 01-Jan-1998 Apex 0022 Ozone 44201 1 01-Jan-1998 Apex 0022 PM 10 total 0-10 μ m STP 1 81102 1 01-Jan-1998 Apex 0022 PM 2.5 - local conditions C-14 88502 3 23-Jan-2007 Boulder City 0601 Ozone 44201 1 01-Jul-1998 Boulder City 0601 PM 10 total 0-10 μ m STP 81102 1 01-Jan-1998 E. Craig Road 0020 Ozone 44201 1 01-Jan-1992 E. Craig Road 0020 PM 10 total 0-10 μ m STP 81102 1 01-Jan-1998 E. Craig Road 0020 PM 2.5 - local conditions C-14 88101 3 01-Jan-2003 E. Craig Road 0020 PM 2.5 - speciation 88101 5 ---
E. Sahara 0539 Carbon monoxide 42101 1 01-Jan-1998
E. Sahara 0539 Sulfur dioxide 42401 1 01-Jan-1998 E. Sahara 0539 Nitrogen dioxide 42602 1 01-Jan-1998
E. Sahara 0539 PM 10 total 0-10 μ m STP 81102 1 01-Jan-1995 Green Valley 0298 PM 10 total 0-10 μ m STP 81102 1 01-Jan-1998 Green Valley 0298 PM 2.5 - local conditions C-14 88101 3 01-Jan-2003 J.D. Smith 2002 Nitrogen di oxide 42602 1 01-Oct-1998
J.D. Smith 2002 Carbon monoxide 42101 1 01-Oct-1998
J.D. Smith 2002 Ozone 44201 1 01-Oct-1998
J.D. Smith 2002 PM 10 total 0-10 μ m STP 81102 1 01-Jan-1998
J.D. Smith 2002 PM 2.5 - local conditions 88101 1 01-Jan-1999
J.D. Smith 2002 PM 2.5 - local conditions C-14 88502 3 01-Jan-2003 Jean 1019 Ozone 44201 1 01-Aug-1998
Jean 1019 PM 10 total 0-10 μ m STP 81102 1 01-Jan-1995
Jean 1019 PM 2.5 - local conditions 88101 1 01-Jan-1999
Jean 1019 PM 2.5 - local conditions C-14 88502 3 26-May-2007
Joe Neal 0075 Ozone 44201 1 01-Jul-2000
Joe Neal 0075 PM 10 total 0-10 μ m STP 81102 1 01-Jan-2001 Joe Neal 0075 Nitrogen dioxide 42602 1 01-Jan-2008
Lone Mountain 0072 Ozone 44201 1 01-Jan-1998
Lone Mountain 0072 PM 10 total 0-10 μ m STP 81102 1 01-Jan-1998 Mesquite 0023 Nitrogen dioxide 42602 1 01-Nov-2001 Mesquite 0023 Ozone 44201 1 01-Oct-2001 Mesquite 0023 PM 10 total 0-10 μ m STP 81102 1 01-Nov-2001
Orr 1021 Carbon monoxide 42101 1 01-Oct-2002 Orr 1021 Ozone 44201 1 01-Apr-2006
Orr 1021 PM 10 total 0-10 μ m STP 81102 1 01-Oct-200221 Site Name Site ID Parameter Description A QS Paramete r Code POC Date Sampling Began Palo Verde 0073 Nitrogen dioxide 42602 1 01-Aug-1998
Palo Verde 0073 Ozone 44201 1 01-Jul-1998
Palo Verde 0073 PM 10 total 0-10 μm STP 81102 1 01-Jul-1998 Paul Meyer Park 0043 Ozone 44201 1 01-Jul-1998 Paul Meyer Park 0043 PM 10 total 0-10 μm STP 81102 1 01-Jan-1998 Southeast Valley 0007 Ozone 44201 1 01-Jan-1980 Southeast Valley 0007 PM 10 total 0-10 μ m STP 81102 1 01-Jan-1998
Sunrise Acres 0561 Carbon monoxide 42101 1 01-Oct-1996
Sunrise Acres 0561 PM 10 total 0-10 μ m STP 81102 1 17-Apr-2004
Sunrise Acres 0561 PM 2.5 - local conditions 88101 1 14-Apr-2004
Sunrise Acres 0561 PM 2.5 - local conditions 88101 2 14-Apr-2004
Sunrise Acres 0561 PM 2.5 - local conditions C-14 88101 3 01-Jul-2005 Walter Johnson 0071 Ozone 44201 1 01-Aug-1998
Walter Johnson 0071 PM 10 total 0-10 μ m STP 81102 1 01-Jul-1995
Winterwood 0538 Carbon monoxide 42101 1 01-Jan-1998
Winterwood 0538 Ozone 44201 2 01-Jul-1979

Note: POC = parameter occurrence code; STP = standard temperature and pressure.22 Monitoring Site Traffic Count Summary

The table below provides traffic count information near monitoring sites.

Site Name Distance to Nearest Roadway 1 Traffic Study Counts from Nearest Roadway 2 Traffic Counts Estimated by

Operator Maximum Traffic Counts for Distance to Roadway 3 Apex 108 meters to U.S. Hwy. 93 2,100 70,000/30,000 Boulder City 57 meters to Indus trial 18,000 40,000/20,000 E. Craig Road 34 meters to Mitchell 4,400 20,000/15,000 E. Sahara 48 meters to Sahara 25,000 20,000/20,000 Green Valley 12.2 meters to S antiago 4,600 10,000/10,000 J.D. Smith 180 meters to Br uce 7,200 70,000/60,000

Jean 1287 meters to State Hwy. 161 2,000 110,000/60,000 Joe Neal 12.2 meters to Rebecca Not available 4,200 10,000/10,000 Lone Mountain 50 meters to Valadez 5,400 40,000/20,000 Mesquite 9.2 meters to Old Mill Rd. Not available 1,000 ≤ 1,000/ ≤ 10,000 Orr 11.9 meters to Katie Not available 5,000 10,000/10,000 Palo Verde 14.7 meters to Pavilion Not available 7,800 10,000/10,000 Paul Meyer 102 meters to New Forrest Dr. Not available 5,200 70,000/30,000 Sunrise Acres 128 meters to Sunrise Not available 3,000 70,000/40,000

Walter Johnson 13 meters to Villa Monterrey 11,000 10,000/ ≤ 10,000 Winterwood 33.8 meters to Club Hous e Dr. Not available 400 20,000/15,000

1 Distance from monitoring path to edge of roadway. 2 Traffic study counts taken or derived from nearest stud y performed by the Nevada Department of Transportation. 3 Tables E-1 & E-2 in 40 CFR 58, Appendix E, are used to determi ne the minimum and maximum distance from the edge of the roadway to the monitoring path or probe. Table E-1 = oz one and nitrogen oxides for urban and neighborhood scale; Table E-2 = CO for neighborhood scale.23 Probe and Path Siting for 2009

1. Apex 2. Boulder City 3. East Craig Road 4. East Sahara 5. Green Valley 6. J.D. Smith 7. Jean 8. Joe Neal 9. Lone Mountain 10. Mesquite 11. Orr 12. Palo Verde 13. Paul Meyer 14. Sunrise Acres 15. Walter Johnson 16. Winterwood24 Figure 2 – Apex

Type: SLAMS Apex (AP) (32-003-0022) Location: 12101 U.S. Highway 93, Las Vegas, NV 89030 Closest Roads: I-15, U.S. Highway 93 UTM X-Coordinate: 667652.800; UTM Y-Coordinate: 4004823.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400 PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 PM 2.5 : Beta Attenuation, Thermo Electron FH 62 C14 Predominant Wind Direction: South Photograph Direction: South

PM 10 PM 2.5 Continuous O 3 Spatial scale Neighborhood Neighborhood Regional Monitoring objective Source-oriented Source-oriented Regional transport Vertical probe placement 4.8 m 4.9 m 3.8 m Unrestricted airflow 360° 360° 360° Spacing from trees None None None Spacing from station to road 108 m 108 m 108 m Distance between collocated monitors 1.4 m 1.4 m —

Ground cover Native desert Native desert — Spacing from supporting structure — — 1.3 m25 PM 10 PM 2.5 Continuous O 3 Obstructions on roof None None — Obstacle distance None None None Probe material — — Teflon Residence time — — 1.9 s26 Figure 3 – Boulder City

Type: SLAMS Boulder City (BC) (32-003-0601) Location: 1005 Industrial Rd., Boulder City, NV 89005 Closest Roads: U.S. Hwy. 93, Industrial Rd. UTM X-Coordinate: 694175.800; UTM Y-Coordinate: 3983670.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400E PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 Predominant Wind Direction: Southwest Photograph Direction: Northwest

PM 10 O 3 Spatial scale Neighborhood Neighborhood Monitoring objective Population exposure Population exposure Vertical probe placement 5.2 m 4.1 m Unrestricted airflow 360° 360° Spacing from trees None None Spacing from station to road 58.0 m 58.0 m Distance between collocated monitors Not applicable — Ground cover Paved, native desert — Spacing from supporting structure — 1.0 m Obstructions on roof None — Obstacle distance None None Probe material — Teflon Residence time — 4.9 s27 Figure 4 – East Craig Road

Type: SLAMS E. Craig Rd (CR) (32-003-0020) Location: 4701 Mitchell St., North Las Vegas, NV 89081 Three Closest Roads: N. Walnut Rd., E. Craig Rd., Mitchell St. UTM X-Coordinate: 671333.900; UTM Y-Coordinate: 4012829.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400A PM 2.5 : Beta Attenuation, Thermo Electron FH 62 C14 PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 PM 2.5 : Speciation, MetOne SASS and URG 3000 Predominant Wind Direction: South Photograph Direction: West

PM 10 O 3 Speciation PM 2.5 Continuous Spatial scale Neighborhood Neighborhood Neighborhood Neighborhood
Monitoring objective Highest concentration Population exposure Population exposure Population exposure Vertical probe placement 5.7 m 4.6 m 5.7 m 5.7 m Unrestricted airflow 360° 360° 360° 360° Spacing from trees None None None None Spacing from station to ro ad 34.0 m 34.0 m 34.0 m 34.0 m Distance between collocated monitors 1.5 m — 1.9 m 1.5 m28 PM 10 O 3 Speciation PM 2.5 Continuous Ground cover Paved, unpaved — Paved, unpaved Paved, unpaved Spacing from supporting structure — 1.2 m — — Obstructions on roof None — None None Obstacle distance 15 m 60 m 15 m 15 m Probe material — Teflon — — Residence time — 5.0 s — —29 Figure 5 – East Sahara

Type: SLAMS East Sahara (ES) (320030539) Location: 4001 E. Sahara Ave., Las Vegas, NV 89104 Three Closest Roads: S. Lamb Bl vd., S. Sandhill Rd., S. Walnut Rd. UTM X-Coordinate: 672250.100; UTM Y-Coordinate: 4001593.000 Operative Schedule: 24 hours Sampling Method: Carbon Monoxide: Gas Filter Correlation API 300E Predominant Wind Direction: Southwest Photograph Direction: East Changes: Proposed move to Jerome Mack Middle School and new shelter, candidate for NCore operations

CO

Spatial scale Neighborhood Monitoring objective Population exposure Vertical probe placement 4.3 m Unrestricted airflow 360° Spacing from trees 39.5 m Spacing from station to road 45.7 m Distance between collocated monitors — Ground cover Asphalt, gravel Spacing from supporting structure 1.3 m Obstructions on roof —30 CO Obstacle distance — Probe material — Residence time 2.7 s31 Figure 6 – Green Valley

Type: SLAMS Green Valley (GV) (32-003-0298) Location: 298 Arroyo Gra nde Blvd., Henderson, NV 89014 Three Closest Roads: Arroyo Grande Blvd., Santiago Dr., N. Stephanie St. UTM X-Coordinate: 675390.700; UTM Y-Coordinate: 3991108.000 Operative Schedule: 24 hours Sampling Method: PM 2.5 : Beta Attenuation, Ther mo Electron FH 62 C14 PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 Predominant Wind Direction: Southwest Photograph Direction: Southeast

PM 10 PM 2.5 Continuous Spatial scale Middle Middle Monitoring objective Population exposure Population exposure Vertical probe placement 4.8 m 4.9 m
Unrestricted airflow 360° 360° Spacing from trees 4.8 m 2.2 m Spacing from station to road 12.2 m 12.2 m
Distance between collocated monitors 2.5 m 2.5 m Ground cover Paved, gravel Paved, gravel Spacing from supporting structure — —32 PM 10 PM 2.5 Continuous
Obstructions on roof — —
Obstacle distance 7.1 m 6.6 m PM Probe material Stainless steel Stainless steel Residence time — —33 Figure 7 – J.D. Smith

Type: NAMS/SLAMS J.D. Smith (JD) (32-003-2002) Location: 1301B Tonopah Ave., North Las Vegas, NV 89030 Three Closest Roads: E. Owens Ave., N. Bruce St., E. Lake Mead Blvd. UTM X-Coordinate: 668778.300; UTM Y-Coordinate: 4006793.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400A Carbon Monoxide: Gas Filter Correlation Analyzer, API 300E PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 PM 2.5 : Beta Attenuation, Thermo Electron FH 62 C14 PM 2.5 : Andersen RAAS2.5-300 FRM Nitrogen Dioxide: Gas Phase Chemiluminescence, API 200E Predominant Wind Direction: Southwest Photograph Direction: North

PM 10 CO PM 2.5 (FRM) NO 2 O 3 PM 2.5 Continuous
Spatial scale Neighborhood Neighborhood Neighborhood Neighborhood Neighborhood Neighborhood
Monitoring objective Population exposure Population exposure Population exposure Population exposure Population exposure Population exposure Vertical probe placement 4.7 m 3.7 m 3.6 m 3.7 m 3.7 m 4.8 m
Unrestricted airflow 360° 360° 360° 360° 360° 360°34 PM 10 CO PM 2.5 (FRM) NO 2 O 3 PM 2.5 Continuous Spacing from trees 35 m 32.8 m 35 m 32.8 m 32.8 m 35 m Spacing from station to road 135 m 135 m 141 m 135 m 135 m 135 m

Distance between collocated monitors 2.6 m — NA — — 2.6 m
Ground cover Paved, grass — Paved, grass — — Paved, grass Spacing from supporting structure — 1.2 m — 1.2 m 1.2 m —

Obstructions on roof None — None — — None
Obstacle distance 3.3 m to wall — 5.1 m to wa ll 4.2 m to wall 4.2 m to wall 5.9 m to wall
Probe material — — — Teflon Teflon —
Residence time — 5.3 s — 5.3 s 5.3 s —35 Figure 8 – Jean

Type: SLAMS Jean (JN) (32-003-1019) Location: 1965 State Highway 161, Jean, NV 89019 Roads: State Highway 161, I-15 UTM X-Coordinate: 648490.100; UTM Y-Coordinate: 3961425.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400E PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 PM 2.5 : Beta Attenuation, Thermo Electron FH 62 C14 PM 2.5 : Andersen RAAS2.5-300 FRM Predominant Wind Direction: Southwest Photograph Direction: Southwest

PM 10 PM 2.5 Continuous O 3 PM 2.5 (FRM)
Spatial scale Regional Regional Regional Regional Monitoring objective Background Background Transport BackgroundVertical probe placement 4.8 m 4.8 m 4 m 2.1 m

Unrestricted airflow 360° 360° 360° 360° Spacing from trees — — — — Spacing from station to road 1,287 m 1,287 m 1,287 m 1,287 m

Distance between collocated monitors 2.7 m 2.7 m — 10 m
Ground cover Native desert, gravel Native desert, gravel — Native desert, gravel36 PM 10 PM 2.5 Continuous O 3 PM 2.5 (FRM)
Spacing from supporting structure — — 1.4 m —

Obstructions on roof — — — — Obstacle distance — — — — Probe material — — Teflon — Residence time — — 1.6 s —37 Figure 9 – Joe Neal

Type: SLAMS Joe Neal (JO) (32-003-0075) Location: 6651 W. Azure Way, Las Vegas, NV 89130 Three Closest Roads: Ann Rd., N. Tenaya Way, W. Azure Way UTM X-Coordinate: 658246.700; UTM Y-Coordinate: 4015402.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400A PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 Nitrogen Dioxide: Gas Phase Chemiluminescence, API 200E Predominant Wind Direction: Northwest Photograph Direction: North

PM 10 O 3 NO 2 Spatial scale Neighborhood Neighborhood Neighborhood Monitoring objective Population exposure Highest concentration Population exposure Vertical probe placement 4.7 m 3.8 m 3.8 m Unrestricted airflow 360° 360° 360° Spacing from trees 8.2 m 5.7 m 5.7 m Spacing from station to road 12.6 m 12.6 m 12.6 m Distance between collocated monitors — — — Ground cover Gravel, grass, natural desert — — Spacing from supporting structure — 0.5 m 2.62 m

Obstructions on roof None — — Obstacle distance None None None Probe material — Teflon Teflon Residence time — 2.1 s 2.1 s38 Figure 10 – Lone Mountain

Type: SLAMS Lone Mountain (LM) (32-003-0072) Location: 3525 N. Valadez St., Las Vegas NV 89129 Three Closest Roads: N. Cimarron Rd., W. Gowan Rd., N. Buffalo Dr. UTM X-Coordinate: 655656.400; UTM Y-Coordinate: 4010319.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400 PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 Predominant Wind Direction: Northwest Photograph Direction: West

PM 10 O 3 Spatial scale Neighborhood Neighborhood Monitoring objective Population exposure Population exposure Vertical probe placement 4.9 m 4.4 m Unrestricted airflow 360° 360° Spacing from trees 9.0 m 12.1 m Spacing from station to road 50.0 m 50.0 m Distance between collocated monitors None — Ground cover Gravel — Spacing from supporting structure — 0.5 m Obstructions on roof None — Obstacle distance 18.0 m 15.5 m Probe material — Teflon Residence time — 10.7 s39 Figure 11 – Mesquite

Type: SLAMS Mesquite (MQ) (32-003-0023) Location: 465 E. Old Mill Rd., Mesquite, NV 89027 Three Closest Roads: I-15, N. Sandhill Blvd., Old Mill Rd. UTM X-Coordinate: 762202.400; UTM Y-Coordinate: 4077598.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400A PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 Predominant Wind Direction: Southwest Photograph Direction: West

PM 10 O 3 Spatial scale Middle Neighborhood Monitoring objective Population exposure Population exposure Vertical probe placement 4.7 m 3.6 m Unrestricted airflow 360° 360° Spacing from trees 24 m 24.0 m Spacing from station to road 5.9 m 7.7 m Distance between collocated monitors — — Ground cover Adjacent raised dirt field — Spacing from supporting structure — 0.5 m Obstructions on roof None — Obstacle distance None None40 PM 10 O 3 Probe material — Teflon Residence time — 10.3 s41 Figure 12 – Orr

Type: SLAMS Orr (OR) (32-003-1021) Location: 1562D E. Katie Ave., Las Vegas, NV 89119 Three Closest Roads: E. Katie Ave., S. Maryland Pkwy., E. Flamingo Rd. UTM X-Coordinate: 667832.143; UTM Y-Coordinate: 3998918.690 Operative Schedule: 24 hours Sampling Method: Carbon Monoxide: Gas Filt er Correlation CO Analyzer, API 300E Ozone: Ultraviolet Absorption, API 400E PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 Predominant Wind Direction: Southwest Photograph Direction: Northwest

PM 10 CO O 3 Spatial scale Middle Neighborhood Neighborhood Monitoring objective Population exposure Population exposure Population exposure Vertical probe placement 4.6 m 4.4 m 4.4 m Unrestricted airflow 360° 360° 360° Spacing from trees 30.0 m 28.0 m 28.0 m Spacing from station to road 11.2 m 11.2 m 11.2 m Distance between collocated monitors — — — Ground cover Paved, grass, gravel — — Spacing from supporting structure — — 0.5 m Obstructions on roof None — —42 PM 10 CO O 3 Obstacle distance No obstacles — — Probe material — — Teflon Residence time — — 3.5 s43 Figure 13 – Palo Verde

Type: SLAMS Palo Verde (PV) (32-003-0073) Location: 333 Pavilion Center Dr., Las Vegas, NV 89144 Three Closest Roads: W. Alta Dr., S. Town Center Dr., W. Charleston Blvd. UTM X-Coordinate: 649914.700; UTM Y-Coordinate: 4004542.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400E PM 2 PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 Predominant Wind Direction: Southwest Photograph Direction: East

PM 10 O3 Spatial scale Middle Neighborhood Monitoring objective Population exposure Population exposure Vertical probe placement 4.9 m 3.7 m Unrestricted airflow 360° 360° Spacing from trees 16.7 m 19.9 m Spacing from station to road 14.7 m 14.7 m Distance between collocated monitors NA — Ground cover Paved Paved Spacing from supporting structure — 0.5 m Obstructions on roof — — Obstacle distance — —44 PM 10 O3 Probe material — Teflon Residence time — 2.1 s45 Figure 14 – Paul Meyer

Type: SLAMS Paul Meyer (PM) (32-002-0043) Location: 4525 New Forest Dr., Las Vegas, NV 89147 Three Closest Roads: S. Rainbow Blvd., W. Tropicana Ave., S. Buffalo Dr. UTM X-Coordinate: 657221.200; UTM Y-Coordinate: 3997162.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400A PM 10 : Beta Attenuation, Thermo Electron FH 62 C14 Predominant Wind Direction: South Photograph Direction: Southwest

PM 10 O 3 Spatial scale Neighborhood Neighborhood Monitoring objective Population exposure Population exposure Vertical probe placement 6.3 m 4.0 m Unrestricted airflow 360° 360° Spacing from trees 17.1 m 21 m Spacing from station to road 102.0 m 102.0 m Distance between collocated monitors — — Ground cover Paved, grass, concrete — Spacing from supporting structure — 0.6 m Obstructions on roof None — Obstacle distance None — Probe material — Teflon Residence time — 2.93 s46 Figure 16 – Sunrise Acres

Type: SLAMS Sunrise Acres (SA) (32-003-0561) Location: 2501 Sunrise Ave., Las Vegas, NV 89101 Three Closest Roads: N. Eastern Ave., Sunrise Ave., N. 26th St. UTM X-Coordinate: 669664.653; UTM Y-Coordinate: 4003698.329 Operative Schedule: 24 hours Sampling Method: Carbon Monoxide: Ga s Filter Correlation, API 300E PM 10 : Beta Attenuation, Ther mo Andersen FH 62 C14 PM 2.5 : Beta Attenuation, Thermo Electron FH 62 C14 PM 2.5 : Andersen RAAS2.5-300 FRM PM 2.5 Collocated: Andersen RAAS2.5-300 FRM Predominant Wind Direction: South Photograph Direction: Northeast

PM 10 CO PM 2.5 (FRM) PM 2.5 FRM Collocated PM 2.5 Continuous Spatial scale Neighborhood Neighborhood Neighborhood Neighborhood Neighborhood
Monitoring objective Population. exposure Highest concentration Highest concentration Highest concentration Highest concentration
Population exposure Highest concentration — — — — Vertical probe placement 4.7 m 3.6 m 2.9 m 2.9 m 4.8 m Unrestricted airflow 360° 360° 360° — 360° Spacing from trees — — — — —47 PM 10 CO PM 2.5 (FRM) PM 2.5 FRM Collocated PM 2.5 Continuous Spacing from station to road 134 m 134 m 134 m 134 m 134 m

Distance between collocated monitors 3.0 m — 2.1 m 2.1 m 3.0 m

Paving Ground cover — Paved Paved Paved Spacing from supporting structure — — — — —

Obstructions on roof None — — — None

Obstacle distance — — 8 m to wall 7 m to wall — 3.99 building height 6.5 m to building — — — —
Probe material — Teflon — — —
Residence time — 0.54 s — — —48 Figure 17 – Walter Johnson

Type: SLAMS Walter Johnson (WJ) (32-002-0071) Location: 7701 Ducharme Ave., Las Vegas, NV 89145 Three Closest Roads: S. Buffal o Dr., Alta Dr., S. Cimarron Rd. UTM X-Coordinate: 656223.000; UTM Y-Coordinate: 4004175.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400 Predominant Wind Direction: Southwest Photograph Direction: West

O 3

Spatial scale Neighborhood Monitoring objective Population exposure Vertical probe placement 3.7 m Unrestricted airflow 360° Spacing from trees 16.5 m Spacing from station to road 13.0 m Distance between collocated monitors — Ground cover — Spacing from supporting structure 0.5 m Obstructions on roof — Obstacle distance 18.4 m Probe material Teflon Residence time 3.1 s49 Figure 18 – Winterwood

Type: NAMS/SLAMS Winterwood (WW) (32- 0030-538), Elevation 1788 Location: 5483 Club House Dr., Las Vegas, NV 89142 Three Closest Roads: E. Sahara Av e., Winterwood Blvd., S. Nellis Blvd. UTM X-Coordinate: 674872.900; UTM Y-Coordinate: 4001556.000 Operative Schedule: 24 hours Sampling Method: Ozone: Ultraviolet Absorption, API 400A Carbon Monoxide: Gas Filter Correlation Analyzer, API 300E Predominant Wind Direction: Southeast Photograph Direction: North

CO O 3

Spatial scale Neighborhood Neighborhood Monitoring objective Population exposure Population exposure Vertical probe placement 3.9 m 3.9 m Unrestricted airflow 360° 360° Spacing from trees 26.4 m 26.4 m Spacing from station to road 42 m 42 m Distance between collocated monitors — — Ground cover Paving, grass, rock — Spacing from supporting structure 0.5 m 0.5 m Obstructions on roof — — Obstacle distance — — Probe material — Teflon Residence time — 3.1 s50 Figure 19 – Visibility Sites

Visibility Monitoring Netw ork (Transmitter/Receiver)
VISIBILITY SITE (Las Vegas) Bank of America – T1 receiver Location: 300 S. Fourth St., Las Vegas, NV 89101 Three closest roads: Fremont St., S. Las Vegas Blvd., Main St. Operative Schedule: 24 hours Equipment: Optec LPV-2
VISIBILITY SITE (Las Vegas) Sunrise Hospital – T1 transmitter Location: 3186 S. Maryland Pkwy., Las Vegas, NV 89109 Three Closest Roads: E. Desert I nn Rd., Vegas Valley Dr., Maryland Pkwy. Operative Schedule: 24 hours Equipment: Optec LPV-251 Carbon Monoxide Monitoring Locations

Figure 20 – Carbon Monoxide Monitoring Locations52 Ozone Monitoring Locations

Figure 21 – Ozone Monitoring Locations in Las Vegas, Boulder City, and Apex53 Figure 22 – Ozone Monitoring Location in Jean54 Figure 23 – Ozone Monitoring Location in Mesquite55 Nitrogen Oxide Monitoring Locations

Figure 24 – Nitrogen Oxide Monitoring Locations in Las Vegas56 Continuous PM 10 Monitoring Locations

Figure 25 – Continuous PM 10 Monitoring Locations in Las Vegas, Boulder City, and Apex57 Figure 26 – Continuous PM 10 Monitoring Location in Jean58 Figure 27 – Continuous PM 10 Monitoring Location in Mesquite59 Continuous PM 2.5 Monitoring Locations

Figure 28 – Continuous PM 2.5 Monitoring Locations in Las Vegas and Apex60 Figure 29 – Continuous PM 2.5 Monitoring Location in Jean61 Filter-Based PM 2.5 Monitoring Locations

Figure 30 – Filter-Based PM 2.5 Monitoring Locations in Las Vegas62 Figure 31 – Filter Based PM 2.5 Monitoring Location in Jean63 Effect of New Regulations on Air Monitoring

On February 9, 2010, EPA released 40 CFR Parts 50 and 58, “Primary National Ambient Air Quality Standards for Nitrogen Dioxide; Final Rule .” In this revision, EPA established requirements for an NO 2 monitoring network with monitors at locations where maximum NO 2 concentrations are expected to occur, including within 50 meters of major road ways, and monitors sited to measure the area-wide NO 2 concentrations that occur more broadly across communities. Clark County is currently investigating siting locations a nd believes that the City Center site (EPA site number 32-003-0016) may meet this requirement. C ity Center is one of the top ten high traffic count areas. It has a diverse traffi c mix that includes older vehicl es, since it is located in an underserved community, and experien ces significant congestion at le ast twice per day. City Center is situated in a unique topographic area that, ba sed on predominant wind flow, receives transport from both the I-15 and South Las Vegas Boulevard (i.e., Las Vegas Strip) corridors, as well as roadside emissions from U.S. Hi ghway 95; since the site is within 50 m of U.S. 95, it may also be suitable for microscale monitoring. In addition, the City Center location has the flexibility to qualify for neighborhood scale monitoring. A prev ious study determined that ozone was undergoing titration by NO x from vehicles on U.S. 95.

On November 12, 2008, EPA released the revised NAAQS for lead (Pb). There are two lead monitoring requirements that Clark County must address: ambient nonsource monitoring and ambient source-oriented monitoring. DAQEM plans to initiate ambient nonsource lead monitoring at the NCore site by January 2011. DAQEM is currently in th e process of identifying potential sources that may trigger required am bient source-oriented lead monitoring.
DAQEM is planning for an NCore site in acco rdance with 40 CFR 58, Appendix D. The location is a new monitoring station at Jerome Mack Mi ddle School that should be operating by January 2011.
With the exception of PM 2.5 FRM samplers, pollen samplers, speciation samplers, and nonroutine special studies, all monitoring instru ments are operated con tinuously all year round.64 Summary of Monitoring Requirements

40 CFR 58 dictates requirements for mainta ining ambient air monitoring networks. DAQEM continuously considers those requirements in its network design, resulting in the conclusions listed beneath each requirement.

1. Determine the highest NAAQS concentration area in the network.

 The area of highest CO concentration is the Sunrise Acres station at 2501 Sunrise Ave., Las Vegas, NV.

 The areas of highest O 3 concentration are the Joe Neal station at 6651 W. Azure Way, Las Vegas, NV and the Walter Johnson stat ion at 7701 Ducharme Ave., Las Vegas, NV.

 The area of highest PM 10 concentration is the Apex station at 12101 U.S. Highway 93, Las Vegas, NV.

 The area of highest annual average PM 2.5 concentration is the S unrise Acres station at 2501 Sunrise Ave.

 The area of highest annual average NO 2 concentration is the J.D. Smith station at 1301b E. Tonopah Dr.

2. Determine representative concentrati ons in areas of high population density.

 City of Las Vegas:

- Annual average CO con centration is 0.6 ppm.

- Annual average O 3 concentration is 0.031 ppm.

- Annual average PM 10 concentration is 21.9  g/m 3

.

- Average PM 2.5 concentration is 8.64  g/m 3

.

- Annual average NO 2 concentration is 0.011 ppm.

 City of Henderson:

- Annual average PM 10 concentration is 19.86  g/m 3

.

- Average PM 2.5 concentration is 6.65  g/m 3

.
 City of Boulder City:

- Annual average O 3 concentration is 0.045 ppm.

- Annual average PM 10 concentration is 14.55  g/m 3

.
 City of Mesquite:

- Annual average O 3 concentration is 0.028 ppm.

- Annual average PM 10 concentration is 20.45  g/m 3

.
3. Determine impacts of signifi cant sources on air quality.

 CO sources: vehicle and non-ve hicle combustion sources

- Impact: zero exceedance days.

 NO 2 sources: vehicle and non-ve hicle combustion sources

- Impact: zero exceedance days.

 PM 2.5 sources: vehicle and non-vehicle combustion sources, fugitive dust

- Impact: zero exceedance days.

 PM 10 sources: fugitive dust, industrial processes

- Impact: One exceedance day in 2009.65 4. Determine general background concentration levels.

 Jean:

- PM 10 : 2009 average = 12.37  g/m 3

.

- PM 2.5 : 2009 average = 4.85  g/m 3

.

- O 3 : 2009 average = 0.041 ppm.

5. Determine extent of regional polluta nt transport among population areas.

 Studies show that ozone transport and re gional contributors ha ve an influence on Clark County, which results in ozone ex ceedances. Smoke from seasonal wildfires contributes significantly to ozone and particulate matter levels in Clark County.

6. Determine welfare-related impacts in rural and remote areas.

 Monitoring at Jean serves a rural area, pr ovides background levels, and can be used to indicate transport from California

 Monitoring at Boulder City serves a rural population

 Monitoring at Mesquite serves a remote popul ation and is located at an outflow transport corridor adjacent a jurisdictional boundary
Clark County Air Monitoring Network

The table below shows that the network meets or exceeds the minimum monitoring requirements in 40 CFR 58.

Pollutant Monitors Required Monitors in service in 2009 CO 0 5 O 3 2 13 SO 2 0 0 NO 2 0 2 PM 10 BAM 4-8 13 PM 2.5 BAM 0 6 PM 2.5 FRM 2 + collocation 3 + collocation
DAQEM uses the following criteria to evaluate the placement and function of the network to meet the requirements of 40 CFR 58:

1. Monitoring objectives 2. AQS scale of representation 3. Emission densities 4. Dispersion modeling 5. Special studies 6. Revised monitoring strategies 7. Sampling schedules 8. Las Vegas area population.66 State implementation and maintenance plan s require no additional instrumentation.67 Quality Assurance Program

The QA Officer conducted performance field ev aluations throughout 2009. These audits indicated that DAQEM is providing inst rument data of sufficient quali ty to satisfy EPA guidance parameters and meet Measurement Quality Objectives.
All gaseous criteria pollutant monitoring inst ruments were field-au dited. There were no SO 2 instruments to be audited. Two sites had NO 2 instruments, and both were evaluated. Five CO instruments were evaluated. Twelve O 3 instruments were also audite d, and there were no failures.

Seven PM 2.5 FRM RAAS samplers at three monitori ng sites were evaluated. A single SASS was audited. Twelve continuous PM 10 C-14 BAMs and six continuous PM 2.5 C-14 BAMs underwent performance evaluations for flow, temperatur e, pressure, and time. Each continuous PM 2.5 BAM is equipped with a Very Sharp Cut Cycl one as a second stag e separator. The PM 2.5 FRM samplers are equipped with a mix of Very Sharp Cu t Cyclone separators and Well Impactor NinetySix impactors. The three PM 2.5 FRM sites (including Sunrise Ac res, which hosts the precision pair) were evaluated twelve ti mes during 2009. Each operational PM 2.5 FRM and the SASS were audited quarterly. All continuous particulate monitors were ev aluated semiannually except the one at the Boulder City site, where sampling wa s terminated for site structure repair.

Evaluations of audit sites were balanced across the calendar year. Any adjustments to the auditing schedule favored pollutant seasonality, e.g., more CO instruments were audited during the winter months and more ozone instruments duri ng the summer months. Audit evaluations of the gaseous pollutants used the transmutation values of slope/intercept create d by calibration activity from the IPS MeteoStar Leading Environment An alysis and Display Syst em, DAQEM’s data acquisition system. Assessments of data flow—fro m collection, to storage, to transfer, to processing with verification, to validation, to review and submittal—indicated consistent, thorough, and acceptable handling regimens.
Precision and accuracy data were uploaded to the AQS database in accordance with 40 CFR 58 requirements, and annual data certifications were completed in accordance with 40 CFR 58.15 requirements.
The following table summarizes the 2009 gaseous and continuous particulate matter event schedule for internal QA performance evaluations.

Date Pollutant Monitoring Stations 2/26/2009 PM 10 Jean 3/12/2009 PM 10 Paul Meyer 3/19/2009 PM 10 Lone Mountain 3/31/2009 PM 10 Joe Neal 5/6/2009 PM 10 Apex, E. Craig Road 5/13/2009 PM 10 Sunrise Acres 7/31/2009 PM 10 Boulder City
8/28/2009 PM 10 Joe Neal, Lone Mountain, Paul Meyer
8/31/2009 PM 10 J.D. Smith, Mesquite68 Date Pollutant Monitoring Stations
9/10/2009 PM 10 Green Valley, Orr
9/11/2009 PM 10 Jean
12/03/2009 PM 10 Craig Road, Orr, Sunrise Acres
12/04/2009 PM 10 Apex, Green Valley, J.D. Smith
12/24/2009 PM 10 Mesquite
2/26/2009 PM 2.5 Jean
5/6/2009 PM 2.5 Apex, E. Craig Road
5/13/2009 PM 2.5 Sunrise Acres
8/31/2009 PM 2.5 J.D. Smith
9/10/2009 PM 2.5 Green Valley
9/11/2009 PM 2.5 Jean
12/03/2009 PM 2.5 E. Craig Road, Sunrise Acres
12/04/2009 PM 2.5 Apex, Green Valley, J.D. Smith
1/27/2009 RAAS Sunrise Acres
2/19/2009 RAAS J.D. Smith
3/27/2009 RAAS Jean
7/21/2009 RAAS J.D. Smith, Sunrise Acres
9/11/2009 RAAS Jean
12/28/2009 RAAS Jean, J.D. Smith, Sunrise Acres 3/27/2009 CO E. Sahara, Winterwood
5/13/2009 CO Winterwood
12/22/2009 CO Orr
12/31/2009 CO J.D. Smith
3/12/2009 O 3 Paul Meyer
3/13/2009 O 3 Walter Johnson
3/19/2009 O 3 Lone Mountain
3/25/2009 O 3 Jean
3/26/2009 O 3 Palo Verde
7/30/2009 O 3 Apex
7/31/2009 O 3 Boulder City
9/10/2009 O 3 Orr
12/23/2009 O 3 E. Craig Road, J.D. Smith
12/24/2009 O 3 Mesquite
3/31/2009 NO 2 Joe Neal
12/31/2009 NO 2 J.D. Smith69 Speciation sampling is grant-funded, and DAQEM ope rates as an informa tional adjunct to the ambient sampling network. Because it does not have a dedicated sampling site in the Chemical Speciation Network, DAQEM can move the speciation samplers th roughout the county to support special project initiatives. In 2009, all sampling events took place at the E. Craig Road site; performance evaluations were conducted on 1/27/2009, 5/6/2009, 9/ 11/2009, and 12/08/2009.70 National Performance Audits

DAQEM is available for participation in the EPA Region 9-sponsored National Performance Evaluation Program. This Thr ough-The-Probe (TTP) performance evaluation, which focuses on gaseous criteria pollutants, is contracted for and scheduled by Region 9. Audit results are made available immediately. DAQEM received a “Pass” a udit report for all TTP performance evaluations in 2009.
The following table shows the 2009 TTP event schedule.

MONITORING STATION POLLUTANT TTP CONDUCTED Walter Johnson O 3 4/13/2009 Orr, Winterwood CO, O 3 4/14/2009 J.D. Smith CO, O 3 , NO 2 4/15/2009 Sunrise Acres CO 4/16/2009
DAQEM annually submits its PM 2.5 FRM sampling network for a Performance Evaluation Program (PEP) audit. Through EPA Region 9, an inde pendent auditor is contracted to perform external field audits. An audit event occurs quarter ly at the same specified site. The contractor submits evaluation results to the AQS database. Because of the manual methods used to audit FRM samplers, the audit findings (in μ g/m 3 ) are not immediately known.

The following table summarizes 2009 PEP audit event activity.

PM 2.5 Sampler Location Date of PEP Audit J.D. Smith 1/07/2009 J.D. Smith 5/13/09 J.D. Smith 8/11/2009 J.D. Smith 11/03/200971 Network Modifications Completed in 2009

The following table summarizes network changes in 2009.

Action Date Reason
Terminated chemiluminescent O 3 operations at Joe Neal site September 2009 Operated as part of 2009 wild fire study; instrument ran between April and September Temporarily shut down O 3 and PM 10 operations at Boulder City site. November 2009 Station repairs72 Network Modifications Proposed

This section describes anticipated and potential changes to the air m onitoring network over the next two years. The actions proposed in this section constitute DAQEM’ s official approval request to EPA Region 9.
Financial, technical, and regulatory challenges may necessitate air monitoring site and equipment terminations. In addition, logistic al issues, such as expired leases , leases due to expire, and administrative issues may require DAQEM to termin ate sites or equipment beyond what is specified in this plan.
Proposed Terminations

Site/Equipment Termination Date Explanation
Apex To be determined Site is located on property of a major stationary
source

PM 2.5 FRMs at J.D. Smith and Jean sites To be determined Anticipate continuous PM 2.5 FEM or ARM deployment at NCore site; Sunrise Acres has the primary and collocated PM 2.5 FRM for the network CO monitoring at J.D. Smith, Orr, E. Sahara, and Winterwood sites To be determined No EPA requir ement for CO monitoring

O 3 monitoring at Orr, Winterwood, Boulder City, Walter Johnson, and Lone Mountain sites To be determined EPA requires only two sites for O 3 monitoring

E. Craig Road, Mesquite, Apex, Jean, and Lone Mountain sites To be determined Unresolved lease issues
Additional Site Closures To be determined Site Closures due to budgetary issues Note: ARM = Approved Regional Method.

Termination Considerations
Apex

. The Apex site is located on the property of a major stationary source. Data trends indicate that the major source may be influencing this s ite, so DAQEM has reconsidered its viability. The site may be reconfigured for meteorological m easurements, including upper air measurements.

PM 2.5 FRM samplers at J.D. Smith and Jean sites. In 2009, DAQEM maintained operations in the PM 2.5 FRM filter-based network to match the gran t level of funding. If this network is reduced, DAQEM will continue to keep using, and applying for, grant funding based on activities outside the PM 2.5 FRM network, including PM 2.5 BAM operations, PM 2.5 speciation sampling, PM 2.5 FEM and ARM efforts, applicable NCore m onitoring, and related training. If deemed appropriate, the criteria in 40 CF R 58.14(c)(3) will comprise DAQE M’s justification for discontinuing filter-based PM 2.5 FRM samplers altogether. DAQEM is anticipating the upgrade of a PM 2.5 BAM to FEM status and a potential ARM de signation in 2010. Sunrise Acres has the primary and collocated PM 2.5 FRM sampler for the network, an d DAQEM anticipates installing a PM 2.5 BAM at the NCore site that ma y receive FEM or ARM designation.73 CO monitoring at J.D. Smith, Orr, East Sahara, and Winterwood sites. Since 40 CFR 58.14(c)(2) no longer requires CO monitoring at these locations , DAQEM may discontinue use of these monitors. DAQEM will evaluate the CO da ta from these sites and the state implementation plan (SIP) requirements, and may choose to te rminate CO monitoring at these sites to conserve resources that can be redirect ed within the m onitoring program.

O 3 monitoring at Orr, Winterwood, Bould er City, Walter Johnson, and Lone Mountain sites. In accordance with 40 CFR 58, DAQEM is only required to operate two O 3 monitoring sites. DAQEM will evaluate the O 3 data from these sites and the SIP requirements, and may choose to terminate O 3 monitoring at these site s to conserve resources that can be redirected within the monitoring program . Comparatively, Orr and Wint erwood sites measure lower O 3 readings in the Las Vegas Valley, and Boulder City has the potential to be considered nonrepresentative. The Walter Johnson and Lone M ountain sites could be considered redundant; however, both have been the high O 3 site in the network. DAQEM will continue to monitor and evaluate O 3 in the urban core, high-concentration areas, background areas, and other areas to characterize transport.
E. Craig Road, Mesquite, Apex, Jean, and Lone Mountain sites. These sites have a variety of issues with lease or occupancy agreements. DAQE M could be required to vacate with little or no notice, which would necessitate termin ating all monitori ng operations.

Additional Site Closures. Due to reductions in the Air Quality Monitoring budget, DAQEM is considering site closures during the 2010 calendar year.
Proposed Relocations and Installations

Relocation/Installation Date Explanation

E. Sahara 2010 Remove monitoring equipment from private property; begin monitoring at nearby Jerome Mack Middle School
E. Craig Road 2010 Move SASS and URG from E. Craig Road to Jerome Mack Middle School to support NCore operations
Apex 2011 Install SODAR to provide u pper air data, facilitate O 3 forecasting & transport Note: SODAR = sonic detection and ranging.

Relocation and Installation Considerations

East Sahara. This site has several administ rative and logistical issues: (1) zoning requires the site to be a wheeled mobile unit; (2) the structure is past its life expectancy; (3) climate control indoors has become increasingly difficult; (4) electric al code prohibits permanent use of extension cords, which are the only way to power this unit; (5) elect ricity prices at th is location have increased significantly; and (6) the lease requires a ll tenants to share the co st of electric usage, which causes monthly fees to vary considerabl y. DAQEM will relocate operations to the Jerome Mack Middle School NCore Site in 2010, less than a mile away.74 East Craig Road. Speciation sampling at this site will be moved to the Jerome Mack Middle School NCore monitoring station before January 2011; the move will include both the SASS and URG samplers.

Apex. DAQEM plans to install a SODAR unit at th e Apex monitoring station. The unit will provide upper-air meteorological data, facilitate po llution forecasting, characterize outflow from the Las Vegas Valley, and help in eval uating pollution transport issues.

Other Considerations

Ivanpah Valley. DAQEM is conducting background monitoring at the Jean site in the Ivanpah Valley. Since there may be construction in this ar ea over the next few years, the Jean site may continue to monitor PM 10 , PM 2.5 , other criteria pollutants, and meteorological parameters.

Spatial monitoring gaps and potenti al high pollutant sites. DAQEM has an interest in filling spatial monitoring gaps and monitoring in high concen tration areas. Through special studies, modeling, and forecasting, DAQEM has projected spatial gaps and elevated pollutant concentrations in specific areas throughout the county: Indian Springs, Laughlin, C oyote Springs, the north-central valley, the southwest valley, and Mt. Charleston have been identified for potential monitoring in the future when resources allow.

Collaboration on monitoring. DAQEM may receive opportunities to exchange information and data with other local agencies, such as the De sert Research Institute (DRI) and the Las Vegas Paiute Tribe. DAQEM may also seek opportunities to enhance current data sets through data exchanges, and may engage in operational exchanges while ensuring the integrity of associated data.
Mobile monitoring. DAQEM would like to implement a mobile monitoring system as an evaluation tool for PM 10 and O 3 throughout Clark County. The mobile monitoring system could be deployed at various locations to assess air quality and help determine where to site permanent monitoring stations. DAQEM’s current resource limita tions do not allow its to implement a mobile monitoring system at this time, but the depa rtment will continue to look for opportunities to fund this project.
In addition to the modifications proposed a bove, DAQEM will evaluate other network changes based on results from the following studies:

1. “PM 10 Saturation Study” (completed December 2005). 2. “Clark County Regional Ozone & Precurs or Study” (completed March 2006). 3. ”Field Measurements and Documentation of Wildfire Event Air Quality Impacts during the 2009 Summer Wildfire Season.” 4. Analysis to determine the ozone nonattainment boundary area (completed July 2004). 5. “Carbon Monoxide Saturation Study” (complet ed April 2002), which confirmed at the time that the network did not miss any CO hot spots. (DAQEM is currently reevaluating the CO network and consid ering site closures.)75 6. The recent designation by EPA of the Thermo Electron FH 62 C14 PM 2.5 BAM as an FEM, or the potential EPA approval of the Thermo Electron FH 62 C14 PM 2.5 BAM as an ARM.76 Status of Monitoring Site Leases

The following table documents the status of le ases for each monitoring site as of March 2009. Expired leases or related events may result in the closure of a m onitoring station at a particular site. This plan constitutes DAQEM’s official re quest to EPA Region 9 to discontinue monitoring under these or similar circumstances.

Site Documentation Owne r Terms Status of Negotiations

Apex Agreement with BLM. However, property is not owned by BLM.

Site is part of property owned and operated by Chemical Lime. Chemical Lime 9/17/20 Complete

Boulder City: 1 pollen site, 1 air qualitymonitoring station (at different locations) 2 agreements City of Boulder City 11/30/15 Complete

City Center Space use permit NDOT Expired

E. Craig Road None L&M Holding County letter to property owneridentifying presence of trailer on site Complete (owner unwilling to provide authorization)

E. Sahara Lease Maycliff Storage 6/30/12 Site being relocated to Jerome Mack Middle School
Green Valley Agreement City of Henderson Ended 3/15/96 Agreement held by Henderson City Attorney

J.D. Smith MOU Clark County School District 5/10/10 Currently in renewal process

Jean ROW grant/ temp. use

permit BLM 6/22/09 Complete (owner unwilling to provide authorization renewal)

Joe Neal MOU Clark County School District 5/10/10 Currently in renewal process

Lone Mountain No agreement LV Water District New interlocalagreement pending, will terminate 12/31/15 Water District seeking board approval for new agreement

Mesquite Agreement with city. However, site is located on an easement on

private land. City of Mesquite 4/30/06 Complete with City (Private land owner has failed to respond and provide authorization)

NLV Airport Agreement Clark County Department of Aviation 10/19/10 Complete

Orr MOU Clark County School District 5/10/10 Currently in renewal process77 Site Documentation Owne r Terms Status of Negotiations

Palo Verde MOU Clark County School District 5/10/10 Currently in renewal process
Paul Meyer Agreement Clark County 4/14/14 Complete

Sunrise Acres MOU Clark County School District 5/10/10 Currently in renewal process

Walter Johnson MOU Clark County School District 5/10/10 Currently in renewal process
Winterwood MOU Clark County 6/30/25 Complete

NOTE: BLM = U.S. Bureau of Land Management; MOU = Memorandum of U nderstanding; NDOT = Nevada Department of Transportation; ROW = right-of-way.78 Air Quality System Database Information

The following table is a compilation of scale a nd objective information in the AQS database.

Site Monitor Measurement S cale Monitor Objective Type Apex O 3 Regional scale Regional transport Apex PM 10 C-14 Regional scale Source oriented Apex PM 2.5 C-14 Regional scale Source oriented Boulder City O 3 Neighborhood Population exposure Boulder City PM 10 C-14 Neighborhood Population exposure E. Craig Road O 3 Neighborhood Population exposure E. Craig Road PM 10 C-14 Neighborhood Highest concentration E. Craig Road PM 2.5 C-14 Neighborhood Population exposure E. Sahara CO Neighborhood Population exposure Green Valley PM 10 C-14 Middle scale Population exposure Green Valley PM 2.5 C-14 Middle scale Population exposure J.D. Smith CO Neighborhood Population exposure
J.D. Smith NO x Neighborhood Highest concentration
J.D. Smith NO 2 Neighborhood Highest concentration
J.D. Smith O 3 Neighborhood Population exposure
J.D. Smith PM 10 C-14 Neighborhood Population exposure
J.D. Smith PM 2.5 FRM Neighborhood Population exposure
J.D. Smith PM 2.5 C-14 Neighborhood Population exposure
Jean O 3 Regional scale Regional transport
Jean PM 10 C-14 Regional scale General/background
Jean PM 2.5 FRM Regional scale General/background
Jean PM 2.5 C-14 Regional scale General/background
Joe Neal NO x Neighborhood Population exposure
Joe Neal NO 2 Neighborhood Population exposure
Joe Neal O 3 Neighborhood Highest concentration
Joe Neal PM 10 C-14 Neighborhood Population exposure
Lone Mountain O 3 Neighborhood Population exposure
Lone Mountain PM 10 C-14 Neighborhood Population exposure Mesquite O 3 Neighborhood Population exposure Mesquite PM 10 C-14 Middle scale Population exposure Orr CO Neighborhood Population exposure
Orr O 3 Neighborhood Population exposure
Orr PM 10 C-14 Neighborhood Population exposure
Palo Verde O 3 Neighborhood Population exposure
Palo Verde PM 10 C-14 Neighborhood Population exposure Paul Meyer O 3 Neighborhood Population exposure79 Site Monitor Measurement S cale Monitor Objective Type Paul Meyer PM 10 C-14 Neighborhood Population exposure Sunrise Acres CO Neighborh ood Highest concentration
Sunrise Acres PM 10 C-14 Neighborhood Population exposure
Sunrise Acres PM 2.5 FRM Neighborhood Highest concentration
Sunrise Acres PM 2.5 FRM Neighborhood Highest concentration
Sunrise Acres PM 2.5 C-14 Neighborhood Highest concentration
Walter Johnson O 3 Neighborhood Population exposure Winterwood CO Neighborhood Population exposure
Winterwood O 3 Neighborhood Population exposure80 Receptor-Measured Criter ia Pollutant Trends

The following pages contain plots of criteri a pollutant measurements. In general, NO 2 has remained steady over the past few years; CO, O 3 , and PM have declined; and SO 2 has remained insignificant.
Figure 32 – Carbon Monoxide Trends

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
YearHigh 8-Hour AverageConcentration (ppm) E. Flamingo / Orr E. Sahara J.D. Smith Sunrise Acres Winterwood

EPA 8-Hour Standard81 Figure 33 – Ozone Trends

45 50 55 60 65 70 75 80 85 90 95 100

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
Year4th Highest 8-Hour AverageConcentration (ppb)

Palo Verde Joe Neal Lone Mountain
Walter Johnson Paul Meyer Park Apex
Jean Winterwood Craig Road
J.D. Smith Boulder City Current EPA 8-Hour Standard 1997 EPA 8-Hour Standard82 Figure 34 – SO 2 Trends

0 20 40 60 80 100 120 140

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
YearHigh 24 Hour AverageConcentration (ppb) E. Sahara Apex* Boulder City* Searchlight* EPA 24 Hour Standard

* - Site Discontinued June 30, 200383 Figure 35 – NO 2 Trends

0 5 10 15 20 25 30 35 40 45 50 55 60

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
YearAnnual Mean (ppb) Apex J.D. Smith Jean E. Sahara Palo Verde Joe Neal EPA Annual Standard84 Figure 36 – Continuous PM 10 Trends

0 10 20 30 40 50 60 70 80 90 100

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
YearAnnual Mean (μg/M3) Apex Boulder City Craig Road E. Flamingo / Orr
Green Valley J.D. Smith Sunrise Acres Paul Meyer Park

Jean Lone Mountain Palo Verde Joe Neal
Mesquite85 Figure 37 – Filter-Based PM 2.5 FRM Trends

0 5 10 15 20 25

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
YearAnnual Mean (μg/M3) J. D. Smith E. Charleston/ Sunrise Acres Jean

EPA Annual Standard86 Figure 38 – Continuous PM 2.5 Annual Mean Trends

0 5 10 15 20 25

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
YearAnnual Mean (μg/M3) Craig Road Green Valley J. D. Smith Sunrise Acres Apex Jean87 Figure 39 – Continuous vs. Filter-Based PM 2.5 Trends

0 2 4 6 8 10 12 14 16 18 20

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
YearAnnual Mean (μg/M3) J.D. Smith FRM J.D. Smith BAM Sunrise Acres FRM Sunrise Acres BAM88 Pollen Network

The pollen network, which is separate from th e NAAQS network, is a unique local service DAQEM provides to Clark County reside nts. It is included in this report for DAQEM use and future reference.
DAQEM operated nine pollen monitoring stations in Clark County during 2009, using the Multidata Model 40 rotorod sampler at each site. The po llen network is located primarily in residential areas, and is intended to assess the general population’s pollen exposure levels . Data are reported to the public through the DAQEM Web site, the media, and faxe d reports; one monitoring station also reports pollen levels to the American Academy of Asthma, Alle rgy, & Immunology three days a week. This same station reports pollen leve ls to the public from July through January. The remaining ten stations report data to the pub lic once a week from February through June.
The two primary producers of allergens in Clark County are the fruitless mulberry and the European olive. The fruitless mulbe rry pollinates in March, the Europe an olive in April; during these months, eight stations operate tw ice a week. Clark County banned fu rther planting of these trees, with the exception of low-pollinating varieties, b ecause of their high levels of pollen (see Section 44 of the Clark County Air Quality Regulations).
The pollen monitoring network is dynamic, and monitoring locations change depending on valley growth, pollen levels, and public requests. The following map depicts the current pollen network.89 Figure 40 – Pollen Sampling Locations in Las Vegas, Boulder City, and Apex