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 ObjectiveAppropriate Siting Scales

Highest Concentration

Population

Source Impact

General / Background

Micro, Middle, Neighborhood(sometimes Urban)

Neighborhood, Urban

Micro, Middle, Neighborhood

Neighborhood, Regional, Global

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

StandardsLevel Time

0.12 ppm

0.08 ppm

1 hr

8 hr

California

Federal

0.09 ppm 1 hr

Ozone

Analyzers– UV Analyzers– Mercury lamp (UV Source)– Analytical wavelength = 254

nm Dasibi 1003AH API 400

UV Analyzer

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

StandardsLevel Time

9 ppm 35 ppm

California

Federal

9 ppm *20 ppm

8 hr1 hr

8 hr1 hr

* except Lake Tahoe: 6 ppm

Carbon Monoxide

Analyzers– NDIR– Gas Filter Correlation– Analytical wavelength 4.7

m TECO 48 Dasibi 3008

NDIR Analyzer

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

0.053 ppm

California

Federal

0.25 ppm 1 hr

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

Chemiluminescence Analyzer

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

0.03 ppm *

0.14 ppm **

0.5 ppm **

California

Federal

0.04 ppm0.25 ppm

24 hr 1 hr

annual average24 hr 3 hr

* primary; ** secondary

Sulfur Dioxide

Analyzers– Fluorescence analyzers– UV excitation light (210

nm)– Measure emitted light (350

nm) TECO 43

Fluorescence Analyzer

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)

Blue Rover

White Rover

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

Remote Meteorological Monitoring (Profiler)

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

Bakersfield monitoring station (Dec 98 to Jan 99) Evaluated continuous real-time particulate

samplers - for possible purchase 25 - 30 samplers New technology (Off-shelf and Prototype) California Regional PM10/PM2.5 Air Quality

Study (CRPAQ) Final report (July 99)

Mexico Border Monitoring

Assist U.S. EPA and SEDESOL (Mexican EPA) in establishing and operating monitoring stations in Tijuana and Mexicali, Mexico

Proposed network to consist of 6 stations in each area (4 full stations, 2 particulate stations)

10 currently sites operational Sites operated by contractor

Summary