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Air Quality Surveillance Branch (AQSB). Air Monitoring Operations Patrick Vaca. Air Quality Surveillance Branch . Branch Overview Air Monitoring Fundamentals Air Quality Monitoring Decisions Air Quality Monitoring Program Data Management AQSB Programs and Special Projects.
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Air Quality Surveillance Branch (AQSB) Air Monitoring Operations Patrick Vaca
Air Quality Surveillance Branch • Branch Overview • Air Monitoring Fundamentals • Air Quality Monitoring Decisions • Air Quality Monitoring Program • Data Management • AQSB Programs and Special Projects
Air Quality Surveillance Branch • Chief, Bill Oslund • Mission: To support the Board’s control by providing air quality data to help define the nature, extent and trend of the state’s air pollution problem.
Branch Sections (5) • Air Quality Monitoring, North • Manager, Larry Molek • Air Quality Monitoring, Central • Manager, Pete Ouchida • Air Quality Monitoring, South • Manager, Curt Schreiber • Operations Support Section • Manager, Vacant • Special Purpose Monitoring • Manager, Ken Stroud
Regulations • California • Health and Safety Code • USEPA • 40 Code of Federal Regulation (CFR) 50 - NAAQS • 40 CFR 53 - Methods • 40 CFR 58 - Monitoring criteria
Definitions • Reference Method • Equivalent Method • Accuracy • Precision • Standard Conditions
Air Quality Monitoring Decisions • Monitoring Objectives • Network Design • Purpose of Monitoring Sites • Scales of Monitoring
Monitoring Objectives • To determine highest concentrations expected to occur in the area covered by network • To determine representative concentrations in areas of high population density • To determine impact on ambient pollution levels of significant source categories • To determine background concentration levels
Network Design • Eventual Use of the Data • Modeling • Baseline conditions • Land use decisions • Planning decisions • Previous Monitoring History
Network Design • Emission Sources • Stationary sources • Mobile sources • Growth and projected new sources • Fugitive Sources • Re-entrained Sources
Network Design • Pollutant Transport • Topography or Terrain • Climatology and Meteorology • Population Levels • Population Centers
Network Design • Available Monitoring Sites • Station Start-up Costs • Equipment • Lease space tenant improvements • Station Operation Costs • Equipment operation and maintenance • Station costs (lease payments, heating, etc..) • Support Personnel (spare parts, repair, etc..)
Purpose of Monitoring Sites • State and Local Air Monitoring Stations (SLAMS) • Nat’l Air Monitoring Stations (NAMS) • Photochemical Assessment Monitoring Stations (PAMS) • Prevention of Significant Deterioration (PSD) • Special Purpose Monitoring (SPM)
Scales of Monitoring • Microscale • Concentrations in air volumes from several meters up to 100 meters • Middle Scale • Concentrations in air volumes from 100 meters up to about .5 Km • Neighborhood • Concentrations in air volumes from .5 Km to 4 Km
Scales of Monitoring • Urban • Concentrations in air volumes from 4 to 50 Km • Regional • Concentrations in rural air volumes from tens to hundreds of Km • National and Global • Concentrations in air volumes from representing a nation or the world as a whole
Monitoring Objectives and Scale Monitoring Objective Appropriate Siting Scales Micro, Middle, Neighborhood (sometimes Urban) Highest Concentration Source Impact Micro, Middle, Neighborhood Neighborhood, Urban Population Neighborhood, Regional, Global General / Background
Station Configuration • ARB has a standard configuration • District may have their own configuration parameters
Station Siting • 40 CFR 58 - Siting Guidelines • If Not Properly Sited - Cannot Rely on Results • Each Pollutant Has Different Requirements Based on Pollutant Properties • Siting Criteria Also Dependent on: • Objective • Purpose • Scale
Air Monitoring Instrumentation • Gaseous • Ozone, CO, NOx, HC, SO2 • Meteorological Instruments • Particulate • Toxics • Calibration Instrumentation
Ambient Air Monitoring Program • Criteria Pollutants • Meteorological • Particulate • Toxics • Acid Deposition
Criteria Pollutant Monitoring • Gaseous Criteria Pollutants • Ozone • Carbon Monoxide • Nitrogen Dioxide • Sulfur Dioxide
Ozone • Colorless gas with a pungent, irritating odor • Continuously monitored with analyzers that measure the amount of UV absorbed by molecular ozone • Sampling Method (Ultraviolet Photometry) • Equivalent Method
Ozone • Standards Level Time 0.09 ppm 1 hr California 0.12 ppm 0.08 ppm 1 hr 8 hr Federal
Ozone • Analyzers • UV Analyzers • Mercury lamp (UV Source) • Analytical wavelength = 254 nm • Dasibi 1003AH • API 400
Carbon Monoxide • Colorless, odorless gas • Continuously monitored with analyzers that take advantage of its strong tendency to absorb IR radiation • Sampling Method (Non-Dispersive Infared Radiation, NDIR) • Reference Method
Carbon Monoxide • Standards Level Time 9 ppm * 20 ppm 8 hr 1 hr California 9 ppm 35 ppm 8 hr 1 hr Federal * except Lake Tahoe: 6 ppm
Carbon Monoxide • Analyzers • NDIR • Gas Filter Correlation • Analytical wavelength 4.7 m • TECO 48 • Dasibi 3008
Nitrogen Dioxide • Reddish-brown gas, with irritating odor • Continuously monitored indirectly with analyzers that measure total oxides of nitrogen • Sampling Method (Gas Phase Chemiluminescence) • Reference Method
Nitrogen Dioxide • Standards Level Time California 1 hr 0.25 ppm Federal 0.053 ppm annual average
Nitrogen Dioxide • Analyzers • Chemiluminescence • NO + O3 NO2 + h (300 - 500 nm) • High energy to generate O3 • Directly measure NO only • Reduce NO2 to NO in converter • Measure total NOx • Calculate NO2 by difference (NOx - NO) • TECO 14B and TECO 42
Sulfur Dioxide • Colorless gas, with a strong suffocating odor • Continuously monitored with analyzers that measure the level of fluorescence emitted by SO2 after being exposed to UV light • Sampling Method (UV Fluorescence) • Equivalent Method
Sulfur Dioxide • Standards Level Time California 24 hr 1 hr 0.04 ppm 0.25 ppm Federal annual average 24 hr 3 hr 0.03 ppm * 0.14 ppm ** 0.5 ppm ** * primary; ** secondary
Sulfur Dioxide • Analyzers • Fluorescence analyzers • UV excitation light (210 nm) • Measure emitted light (350 nm) • TECO 43
Calibration Equipment • Required to perform nightly calibrations • Equipment • Dilution Calibration Systems • Pure Air Generator • Certified Cylinder Gases
Meteorological Monitoring Program • Transport of pollutants • Modeling • Ag Burn • Met One Instruments • EPA QA Handbook Volume IV
Meteorological Instruments • Wind Direction • Wind Speed • Temperature • Relative Humidity • Rain Fall • Atmospheric Pressure
Data Management • Data Quality Objectives (DQO’s) • Quality Control • Instrument technician training • Periodic training on existing and new equipment • Documentation • Equipment calibrations
Data Management • Quality of data • Accuracy and Precision • Completeness • Valid Hour and Day • 30 continuous minutes in any one hr • 24 hr period must have in each 8 hr segment (0000-0759,0800-1559,1600-2359) at least 6 hrs of valid hourly data
Data Management • Data Review and Editing • Air Quality Data Acquisition System (AQDAS) • Collects and processes data from statewide air monitoring network • First, second, third level reviews • Checked against strip charts and calibrations • Complete data set • Reviewed for accuracy and consistency
Data Management • Data Submittal • Upload to Aerometric Information Retrieval System (AIRS) database • Air Quality Data Actions • data deletion • data correction
AQSB Programs and Special Projects • AQDAS II • Mobile Air Monitoring (Rover’s) • Remote Meteorological Monitoring (Profiler’s) • Saturation Sampling • Instrument Intercomparison Study • Mexico Border Monitoring
AQDAS II • Next generation data acquisition system • Network of Local Area Networks (LAN’s) using Environmental Monitoring Company (EMC) PC based software • Provide central database for air monitoring data • Data collected and edited on central system • Generate data in AIRS format
Mobile Air Monitoring (Rover) • Short to medium ambient air monitoring • Full air monitoring stations • Two platforms • GMC Van (Blue Rover) • Wells Cargo Trailer (White Rover) • Current deployments • Tecate, Mexico • San Diego (Barrio Logan District)
Saturation Sampling • Provide rapid and cost effective temporal and spacial distribution of pollutants • Sampler consists of (2) 5-liter tedlar bags, PC board, pump and battery • Samples for CO and particulates only