Air Quality Surveillance Branch AQSB Air Monitoring Operations
Air Quality Surveillance Branch (AQSB) Air Monitoring Operations Patrick Vaca
Air Quality Surveillance Branch u. Branch Overview u. Air Monitoring Fundamentals u. Air Quality Monitoring Decisions u. Air Quality Monitoring Program u. Data Management u. AQSB Programs and Special Projects
Air Quality Surveillance Branch u. Chief, Bill Oslund u. 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) u Air Quality Monitoring, North – Manager, Larry Molek u Air – Manager, Pete Ouchida u Air – Quality Monitoring, Central Quality Monitoring, South Manager, Curt Schreiber u Operations Support Section – Manager, Vacant u Special – Purpose Monitoring Manager, Ken Stroud
Regulations u California – Health and Safety Code u USEPA – – – 40 Code of Federal Regulation (CFR) 50 NAAQS 40 CFR 53 - Methods 40 CFR 58 - Monitoring criteria
Definitions u. Reference Method u. Equivalent Method u. Accuracy u. Precision u. Standard Conditions
Air Quality Monitoring Decisions u. Monitoring Objectives u Network Design u Purpose of Monitoring Sites u Scales of Monitoring
Monitoring Objectives u To determine highest concentrations expected to occur in the area covered by network u To determine representative concentrations in areas of high population density u To determine impact on ambient pollution levels of significant source categories u To determine background concentration levels
Network Design u. Eventual – – Use of the Data Modeling Baseline conditions Land use decisions Planning decisions u. Previous Monitoring History
Network Design u. Emission – – – Sources Stationary sources Mobile sources Growth and projected new sources u. Fugitive Sources u. Re-entrained Sources
Network Design u. Pollutant Transport u. Topography or Terrain u. Climatology and Meteorology u. Population Levels u. Population Centers
Network Design u Available Monitoring Sites u Station Start-up Costs – – Equipment Lease space tenant improvements u Station – – – Operation Costs Equipment operation and maintenance Station costs (lease payments, heating, etc. . ) Support Personnel (spare parts, repair, etc. . )
Purpose of Monitoring Sites u State and Local Air Monitoring Stations (SLAMS) u Nat’l Air Monitoring Stations (NAMS) u Photochemical Assessment Monitoring Stations (PAMS) u Prevention of Significant Deterioration (PSD) u Special Purpose Monitoring (SPM)
Scales of Monitoring u Microscale – Concentrations in air volumes from several meters up to 100 meters u Middle – Scale Concentrations in air volumes from 100 meters up to about. 5 Km u Neighborhood – Concentrations in air volumes from. 5 Km to 4 Km
Scales of Monitoring u Urban – Concentrations in air volumes from 4 to 50 Km u Regional – Concentrations in rural air volumes from tens to hundreds of Km u 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 Highest Concentration Micro, Middle, Neighborhood (sometimes Urban) Source Impact Micro, Middle, Neighborhood, Urban Population General / Background Neighborhood, Regional, Global
Station Configuration u ARB has a standard configuration u District may have their own configuration parameters
Station Siting u 40 CFR 58 - Siting Guidelines u If Not Properly Sited - Cannot Rely on Results u Each Pollutant Has Different Requirements Based on Pollutant Properties u Siting Criteria Also Dependent on: – – – Objective Purpose Scale
Air Monitoring Instrumentation u Gaseous – Ozone, CO, NOx, HC, SO 2 u Meteorological Instruments u Particulate u Toxics u Calibration Instrumentation
Ambient Air Monitoring Program u. Criteria Pollutants u. Meteorological u. Particulate u. Toxics u. Acid Deposition
Criteria Pollutant Monitoring u Gaseous Criteria Pollutants – – Ozone Carbon Monoxide Nitrogen Dioxide Sulfur Dioxide
Ozone u Colorless gas with a pungent, irritating odor u Continuously monitored with analyzers that measure the amount of UV absorbed by molecular ozone u Sampling Method (Ultraviolet Photometry) u Equivalent Method
Ozone H Standards Level Time California 0. 09 ppm 1 hr Federal 0. 12 ppm 1 hr 0. 08 ppm 8 hr
Ozone u Analyzers – – – UV Analyzers Mercury lamp (UV Source) Analytical wavelength = 254 nm u Dasibi 1003 AH u API 400
UV Analyzer
Carbon Monoxide u Colorless, odorless gas u Continuously monitored with analyzers that take advantage of its strong tendency to absorb IR radiation u Sampling Method (Non-Dispersive Infared Radiation, NDIR) u Reference Method
Carbon Monoxide H Standards Level Time 9 ppm * California 20 ppm Federal 9 ppm 35 ppm * except Lake Tahoe: 6 ppm 8 hr 1 hr
Carbon Monoxide u Analyzers – – – NDIR Gas Filter Correlation Analytical wavelength 4. 7 m u TECO 48 u Dasibi 3008
NDIR Analyzer
Nitrogen Dioxide u Reddish-brown gas, with irritating odor u Continuously monitored indirectly with analyzers that measure total oxides of nitrogen u Sampling Method (Gas Phase Chemiluminescence) u Reference Method
Nitrogen Dioxide u Standards Level California 0. 25 ppm Federal 0. 053 ppm Time 1 hr annual average
Nitrogen Dioxide u Analyzers – – – – Chemiluminescence NO + O 3 NO 2 + h (300 - 500 nm) High energy to generate O 3 Directly measure NO only Reduce NO 2 to NO in converter Measure total NOx Calculate NO 2 by difference (NOx - NO) u TECO 14 B and TECO 42
Chemiluminescence Analyzer
Sulfur Dioxide u Colorless gas, with a strong suffocating odor u Continuously monitored with analyzers that measure the level of fluorescence emitted by SO 2 after being exposed to UV light u Sampling Method (UV Fluorescence) u Equivalent Method
Sulfur Dioxide u Standards Level California 0. 04 ppm 0. 25 ppm Federal 0. 03 ppm * 0. 14 ppm ** 0. 5 ppm ** * primary; ** secondary Time 24 hr 1 hr annual average 24 hr 3 hr
Sulfur Dioxide u Analyzers – – – Fluorescence analyzers UV excitation light (210 nm) Measure emitted light (350 nm) u TECO 43
Fluorescence Analyzer
Calibration Equipment u. Required to perform nightly calibrations u. Equipment – Dilution Calibration Systems – Pure Air Generator – Certified Cylinder Gases
Meteorological Monitoring Program u. Transport of pollutants u. Modeling u. Ag Burn u. Met One Instruments u. EPA QA Handbook Volume IV
Meteorological Instruments u Wind Direction u Wind Speed u Temperature u Relative Humidity u Rain Fall u Atmospheric Pressure
Data Management u Data Quality Objectives (DQO’s) u Quality Control – – Instrument technician training Periodic training on existing and new equipment Documentation Equipment calibrations
Data Management u Quality – – Accuracy and Precision Completeness u Valid – – of data 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 u 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 u Data Submittal – Upload to Aerometric Information Retrieval System (AIRS) database – Air Quality Data Actions » » data deletion data correction
AQSB Programs and Special Projects u AQDAS II u Mobile Air Monitoring (Rover’s) u Remote Meteorological Monitoring (Profiler’s) u Saturation Sampling u Instrument Intercomparison Study u Mexico Border Monitoring
AQDAS II u Next generation data acquisition system u Network of Local Area Networks (LAN’s) using Environmental Monitoring Company (EMC) PC based software u Provide central database for air monitoring data u Data collected and edited on central system u Generate data in AIRS format
Mobile Air Monitoring (Rover) u Short to medium ambient air monitoring u Full air monitoring stations u Two platforms – GMC Van (Blue Rover) – Wells Cargo Trailer (White Rover) u Current deployments – Tecate, Mexico – San Diego (Barrio Logan District)
Blue Rover
White Rover
Saturation Sampling u u u 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
Remote Meteorological Monitoring (Profiler) u u u Provides upper air meteorological data Remote sensing doppler radar w/ acoustic sources Measures horizontal wind speed and direction and virtual temperature profiles
Instrument Intercomparison Study u Bakersfield monitoring station (Dec 98 to Jan 99) u Evaluated continuous real-time particulate samplers - for possible purchase u 25 - 30 samplers u New technology (Off-shelf and Prototype) u California Regional PM 10/PM 2. 5 Air Quality Study (CRPAQ) u Final report (July 99)
Mexico Border Monitoring u Assist U. S. EPA and SEDESOL (Mexican EPA) in establishing and operating monitoring stations in Tijuana and Mexicali, Mexico u Proposed network to consist of 6 stations in each area (4 full stations, 2 particulate stations) u 10 currently sites operational u Sites operated by contractor
Summary
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