Division of Air Quality

Ambient Monitoring

Donnie RedmondSection ChiefMay 7, 2014

Topics to be CoveredAmbient Monitoring

Why do we do it?Who determines how many to operate?How do we decide where to put them?What do monitors look like? (Pictures!)

Issues on the Horizon

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Ambient Monitoring: Why?EPA requirements

Highest concentrationsPopulation exposureBackground

ResearchPublic health effects re pollutant levelsTo better understand control strategiesPublic interest

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Ambient Monitoring: What? EPA regulations lay out minimum

requirementsNumber of monitorsWhere to locate themHow long to operate them

Different rules for each pollutantSame standards apply across the nation

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Example: Ozone requirementsAny metro area (MSA) with 350,000 people

Must have at least one ozone monitorIf >85% of the standard, must have two

Any MSA with at least 50,000 peopleMust have a monitor if >85% of standard

At least one monitor in each area must be for maximum concentration

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Ozone monitoring req’ts (cont.)Eight NC metro areas have >350,000

peopleCharlotte, Raleigh, Durham, Greensboro,

Winston-Salem, Asheville, Hickory, FayettevilleEach must have at least one monitorSecond monitor required if near ozone standard

Seven other MSAs with 50,000-350,000 peopleWilmington, Greenville, Rocky Mount,

Jacksonville, Goldsboro, Burlington, New BernOne monitor required if >85% of standard

85% of the standard (75ppb) is ~64 ppb6

Ozone monitoring req’ts (cont.)Other considerations

Additional monitors may help reduce the size of a nonattainment area

Rural monitors may help determine transport of pollution

Number of required ozone monitors can add up quickly!

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Other pollutantsPM2.5

Population and pollutant concentrationNO2

Population and traffic volumeSO2

Population and emissions weighted indexLead

Emissions-basedCO

No population-based requirementsAdditional background monitors in support of PSD

permitting8

Ambient Monitoring: Who?Statewide network

Regional office staff operates the monitorsElectronics calibration/repair shop in RaleighTwo labs in RaleighCentral office does QA, SOPs, and reporting

Local programsMecklenburg, Forsyth, Western NC

Cherokee tribeFederal agencies also operate monitors in NC

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Site CharacteristicsMust meet EPA requirements, including

Distance from trees, buildings, roadsNearby emissions sourcesPrevailing wind directionHeight of sample probe above ground

Other considerationsSafety of technicians (traffic, terrain)Access to power and phoneCost to use site (free is good!)Co-located with other instruments

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Quality Assurance requirementsChemists/statisticians review, validate, and

report all the data CalibrationsPower failures“Exceptional events”, i.e., firesMonitor performance issues

Temperature, humidity, leaksInsects, varmintsCompleteness

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Issues on the HorizonNew ozone standard (2015)

Could require monitors in smaller metro areasCould extend the ozone monitoring season

SO2 source-oriented monitoring (2016)Major concerns regarding resources and

logisticsIntroduction of new high tech sensing

devicesCitizens can take real-time local measurements

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Particulate at Goldsboro

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Ozone at Mocksville

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Near road monitor in Raleigh

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Questions?Donnie Redmond

Ambient Monitoring Section Chief919-707-8468donnie.redmond@ncdenr.gov

References 40 CFR Part 58, Appendix D DAQ website

http://www.ncair.org/

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