Maricopa County •Air Quality Department.- Air Monitoring Division January 31, 2012

• 2145 S. 11 Ave., Suite170 Phoenix, Arizona 85007 Phone: 602-258-5155 Fax: 602-258-0666 Michael Flagg USEPA Region 09 Mail Code: AIR

7 75 Hawthorne Street San Francisco, CA 94105 RE: Relocation
of the Pinnacle Peak and Mesa sites Mr. Flagg: The purpose of this letter
is to inform youthat the Maricopa County Air Quality Department (MCAQD) proposes
to shut down the Mesa site (04-013-1003)

asof January 31, 2012 and movethe PM 10 and PM 25 monitors
to the Tempe site (04-013- 4005). These two new monitors will be continuous. The Tempe site is the best location for the monitors because of the relative short distance between the sites and similarities in pollution sourcesand population (see attached report). Additionally, both monitors will be established

in EPA AQS database
as special purpose monitors and will be evaluated after one yearof data has been collected. The start date for the new monitors will be February 24, 2012. Additionally, MCAQD shut down the Pinnacle Peak site (04-013-2005)

on November 18, 2011 after receiving

aletter from the land ownerto remove the site (see attached). MCAQD

is currently
in negotiations with the sameland ownerto reestablish the site within

amile of the original location. The start date for the new Pinnacle Peak site is August 2012. Regards, Ben Davis Air Monitoring Manager Enc. cc: William Wiley MCAQD Eric C. Massey ADEQ Lindy Bauer MAG FWcIEllvED Protecting ourmost vital, natural resource;air. www.maricopa.gov/ag

FEB 13 2012—Maricopa County Air Monitoring Division proposal
to movethe particulate monitors from the Mesa to the Background: Tempe monitoring site The Maricopa County Air Quality Department’s (MCAQD) Mesa air pollution monitoring site, AQS# 04-013-1003,

is located
at 310 S. Brooks Avenue
in Mesa, AZ. This location

is a City of Mesa property housing the Brooks Reservoir,
an underground water storage site. The City of Mesa provides
usasmall roomwithin their maintenance buildings

in addition
to spaceonthe roof to runour equipment (Figure 1). This monitoring site has been continually operating

at this location since 1978 and currently monitors PM1O, and PM2.5. The CO monitor

is continuous, but both the PM1O and PM2.5 monitors arefilter-based Federal Reference Methods operating
on
a1-in-6 and 1-in-3 day operating schedule, respectively. There arealso meteorological monitors on site, including wind speed and direction. Figure
1. Maintenance building
at the City of Mesa Brooks Reservoir housing the Mesa monitoring site. The pollution design values at the Mesa site are relatively low compared with the rest of the network; the 2005-2009 average design value for the three parameters

is listed in Table
1. The last time that there wasanexceedance

at the Mesa site of the CO standard wasin 1980. The only exceedance

of the PM1O standard occurred

in 2003, while the only exceedance

of the PM2.5 standard occurred on July 5, 2011, during

asummerdust storm.

1Table
1. Design values for parameters

at the Mesa monitoring site (source: 2010 MCAQD Network Assessment). Parameter Average design Ranking amongnetwork (#1 value (2005-2009) being highest design value) CO 3.02 PPM #10 out of 13 monitoring sites PM1O 85.8 ig/m 3 #13 out of 15 monitoring sites PM2.5 17.8 ig/m 3

#4 out of 4 monitoring sites Construction: In August 2011, MCAQD wasnotified by the City of Mesa of pending major construction

to upgrade the pumping infrastructure

at the Brooks Reservoir site. All electrical powerto the site will be cut while construction

is underway, which
is scheduled

to begin in February 2012 and could be underway for oversix months. Following completion
of the construction and resumption
of powerat the site, MCAQD will construct

anewsite close to the original location. This is expected
to take upto two months. Figure

2 shows construction equipment being gathered
at the Brooks Reservoir. Figure
2. Construction material being gathered
at the Brooks Reservoir site in January 2012. Construction

is expected
to commence
on February

1, 2012.

2Proposal for Moving Monitor: It is proposed
to movethe Mesa PM1O and PM2.5 monitors
to the Tempe monitoring site (04- 013-4005) (Figure 3). Tempe already has
aCO monitor,
sothe Mesa CO monitor will simply be shut off during the construction period. The Tempe site is the closest existing site to Mesa, being 4.0 miles away;the next closest

is the South Scottsdale site (04-013-3003), which
is 4.6 miles away. Figure
3. Tempe Monitoring Site, the proposed temporary location of the Mesa PM1O and PM2.5 monitors. MCAQD proposesthat Tempe

is an appropriate substitute for Mesa not only because

it is closest, but also because manysource characteristics and population demographics
aresimilar. Table

2 shows data from the 2008 MCAQD emissions inventory, with spatial data taken from the 2010 MCAQD Network Assessment.

A four-mile buffer wasdrawn around each site and known PM1O and PM2.5 emission sourcesweresummed and averaged for their annual emissions. Tempe

is similar to Mesa in PM1O emission, but PM2.5 emissions aremorethan three times greater. South Scottsdale has far fewer PM1O and PM2.5 emissions. Table 2. Data from the 2008 MAQD Emissions Inventory onPM1O and PM2.5 sourceswithin

afour mile radius of monitoring site. Site Average Sum of PM1O Average Sum of PM2.5 Annual PM1O Annual PM2.5 Annual Annual Emissions Emissions Emissions Emissions Mesa
1,397 lbs 96,418 lbs 797 lbs 55,008 lbs

3Table

3 gives information
ontraffic sourcesof pollution

in afour-mile radius around each monitor. All three sites are very similar, but Tempe

is moresimilar than South Scottsdale. Table 3-Traffic Counts (from 2007) within

afour-mile radius of monitoring site. Site Arterial Road AWT Freeway AWT Average Traffic Mesa 27,782 167,141 97,462 Tempe 28,599 161,609 95,104 South Scottsdale 20,972 154,993 87,983 Table
4 displays the sumand density of population within

afour-mile radius of the monitoring sites. Mesa represents significantly more population than the other sites, but Tempe

is the most similar among nearby sites. Table 4-Population data (from the 2000 Census) within

afour-mile radius of monitoring site. Site
Sum of Population Population Density (within Census Blocks) (population perkm 2 ) Mesa 263,948
2,615 Tempe 210,610
2,605 South Scottsdale 131,772
2,113 Conclusion: MCAQD proposes
to movethe Mesa PM1O and PM2.5 filter based monitors
to the Tempe site. These two newmonitor will be continuous. The Tempe site is the best option for the monitors because of the relative short distance between the sites and similarities

in pollution sourcesand population.

4Additionally,bothmonitorswillbeestablished

inEPAAQSdatabase
asspecialpurposemonitors andwillbeevaluatedafteroneyearofdatahasbeencollected.Uponcompletion
oftheCityof Mesaconstruction,thesitewillbereconstructedandevaluatedforwhatmonitorswillbeplaced atthenewsite.

5TROON COUNTRY CLUR Cetie Aucubo CoopeseUve E3enc Wary November

1, 2011 Maricopa County Air Quality Department 2145 South 11th Ave. Suite 170 Phoenix,AZ 85007 Attention: Ben Davis, Air Monitoring Manager RE: Equipment located at 25000 N. Windy Walk Dr. Mr. Davis, Troon Country Club would like to discontinue

its cooperative with the.county

to host the air quality equipment. Please have the equipment removed
at yourearliest convenience. Thank you, Jo iA. ewell Co Her OCX

1J.. Windy Wk DvubSco Ari 5255 ‘(40 5-43iti F )) 83-5233 www.trooncc.com