California Photochemical Assessment Monitoring Stations

(PAMS) 2000

California Photochemical Assessment Monitoring Stations

(PAMS) 2000By Donald HammondBy Donald Hammond

February 13, 2001February 13, 2001

California Air Resources BoardCalifornia Air Resources Board

Monitoring and Laboratory DivisionMonitoring and Laboratory Division

IntroductionIntroduction

1989- ARB begins seasonal (summer) 1989- ARB begins seasonal (summer) sampling for hydrocarbonssampling for hydrocarbons

1991- ARB’s Sacramento Area Winter Study 1991- ARB’s Sacramento Area Winter Study 1994- Federal regulations require States to 1994- Federal regulations require States to

establish Photochemical Assessment establish Photochemical Assessment Monitoring Stations (PAMS) in ozone Monitoring Stations (PAMS) in ozone non-attainment areas (1-hour standard). non-attainment areas (1-hour standard). PAMS begins with several California PAMS begins with several California Districts. Districts.

California Air Districts in the 2000 PAMS ProgramCalifornia Air Districts in the 2000 PAMS Program

South Coast Air Quality Management South Coast Air Quality Management District (AQMD)District (AQMD)

Ventura County Air Pollution Control Ventura County Air Pollution Control District (APCD)District (APCD)

San Diego County APCDSan Diego County APCD Sacramento Metropolitan AQMDSacramento Metropolitan AQMD San Joaquin Valley Unified APCDSan Joaquin Valley Unified APCD Santa Barbara County APCDSanta Barbara County APCD

ARB’s role in PAMSARB’s role in PAMS Provide program development coordinationProvide program development coordination Provide quality management support for the Provide quality management support for the

Districts:Districts:

Review QA/QC plansReview QA/QC plans

Station Probe AuditsStation Probe Audits

Laboratory Audits (ARB and Federal)Laboratory Audits (ARB and Federal)

Whole Air Sample ComparisonsWhole Air Sample Comparisons

ARB’s role in PAMS- continuedARB’s role in PAMS- continued

Have provided laboratory services to some Have provided laboratory services to some Districts (Sacramento and San Joaquin) by Districts (Sacramento and San Joaquin) by contractcontract

Coordinate PAMS data analysis Coordinate PAMS data analysis (STI reports May 1999) (STI reports May 1999)

Assist in the development of the California Assist in the development of the California Alternative Plan (CAP) Alternative Plan (CAP)

Monitoring Stations Types 1, 2, 3, and 4Monitoring Stations Types 1, 2, 3, and 4 1: Upwind / Background 1: Upwind / Background 2: Maximum Emissions from Central 2: Maximum Emissions from Central

Business District. Requires precursor Business District. Requires precursor measurement of both HCs and carbonyls.measurement of both HCs and carbonyls.

3: Downwind maximum ozone station3: Downwind maximum ozone station 4: Extreme downwind station (transport)4: Extreme downwind station (transport)

General Sampling Requirements for Ozone PrecursorsGeneral Sampling Requirements for Ozone Precursors Type 2 stations collect eight 3-hour samples Type 2 stations collect eight 3-hour samples

every day for hydrocarbons and carbonylsevery day for hydrocarbons and carbonyls Type 1, 3, and 4 stations collect eight 3-Type 1, 3, and 4 stations collect eight 3-

hour samples every third day for hour samples every third day for hydrocarbonshydrocarbons

South Coast AQMD is performing the full South Coast AQMD is performing the full plan while other California Districts are on plan while other California Districts are on the California Alternative Planthe California Alternative Plan

California Alternative PlanCalifornia Alternative Plan Requires less sampling for hydrocarbons Requires less sampling for hydrocarbons

and carbonyls at all station typesand carbonyls at all station types Type 2 stations collect four 3-hour Type 2 stations collect four 3-hour

samples every third day for hydrocarbons samples every third day for hydrocarbons and carbonylsand carbonyls

Type 1, 3, and 4 stations collect four 3-Type 1, 3, and 4 stations collect four 3-hour samples every third day for hour samples every third day for hydrocarbonshydrocarbons

California Alternative Plan -continuedCalifornia Alternative Plan -continued Increase sampling on episode days Increase sampling on episode days Collect hourly Total Non-Methane Organic Collect hourly Total Non-Methane Organic

Compounds (TNMOC) at all stations Compounds (TNMOC) at all stations every day every day

California PAMS: 25California PAMS: 25

South Coast AQMD- 7 stations South Coast AQMD- 7 stations Ventura County APCD- 3 stations Ventura County APCD- 3 stations San Diego County APCD- 4 stationsSan Diego County APCD- 4 stations Sacramento Metropolitan AQMD- 4 stationsSacramento Metropolitan AQMD- 4 stations San Joaquin Valley Unified APCD- 6 stationsSan Joaquin Valley Unified APCD- 6 stations Santa Barbara County APCD- 1 stationsSanta Barbara County APCD- 1 stations Several Upper Air ProfilersSeveral Upper Air Profilers

Target Precursors ReportedTarget Precursors Reported 56 hydrocarbons 56 hydrocarbons TNMOC (43102) from hourly monitors such TNMOC (43102) from hourly monitors such

as the TEI 55 C or Method 164as the TEI 55 C or Method 164 TNMOC (43102) sum of all species from TNMOC (43102) sum of all species from

Gas Chromatograph Flame Ionization Gas Chromatograph Flame Ionization Detector GC/FID or Method 200 Detector GC/FID or Method 200

TNMOC (43102) from GC Pre-concentration TNMOC (43102) from GC Pre-concentration Direct (PD) FID or Method 12Direct (PD) FID or Method 12

Carbonyls (formaldehyde, acetaldehyde)Carbonyls (formaldehyde, acetaldehyde)

TNMOC at Fresno Parlier for 1999 - Methods 164, 12, and 200*

0

100

200

300

400

500

600

700

800

900

Sampling Date

TN

MO

C (

PP

BC

)

Method 164- TECO 55 / hourlyMethod 12- canister / PDFIDMethod 200- canister / all GC peaks

dsh/pe&s/4-11-0

*Samples taken form 6-9 a.m. PDSTMethod 164 samples below 150 not included

Bias Issues- caution data user!Bias Issues- caution data user! Are calibration gases traceable to the National Are calibration gases traceable to the National

Institute of Standards and Technology Institute of Standards and Technology (NIST)?(NIST)?

Are oxygenates part of the TNMOC (43102)?Are oxygenates part of the TNMOC (43102)? Do Limit of Detection LOD differences Do Limit of Detection LOD differences

among laboratories and methods have an among laboratories and methods have an effect?effect?

Sensitivity requirements (are the methods Sensitivity requirements (are the methods adequate for today’s samples?)adequate for today’s samples?)

Limit of DetectionLimit of Detection

TEI or TECO 55 C, Method 164 had a LOD TEI or TECO 55 C, Method 164 had a LOD of 150 PPBC, after modification in 2000 the of 150 PPBC, after modification in 2000 the LOD was lowered to about 75 PPBCLOD was lowered to about 75 PPBC

GC/FID Method 200 LOD vary from 0.1 to GC/FID Method 200 LOD vary from 0.1 to 1 PPBC depending on Laboratory (five 1 PPBC depending on Laboratory (five district and two contract laboratories district and two contract laboratories operated during year 2000 for PAMS)operated during year 2000 for PAMS)

GC/PDFID Method 12 has an LOD of GC/PDFID Method 12 has an LOD of 30 PPBC30 PPBC

Relationship of LOD and Method BiasRelationship of LOD and Method Bias GC/FID Method 200 may undercount GC/FID Method 200 may undercount

TNMOC if LOD is higher than many of the TNMOC if LOD is higher than many of the species species

U.S. EPA Technical Advisory Document U.S. EPA Technical Advisory Document recommends a minimum LOD of 1 PPBC recommends a minimum LOD of 1 PPBC for Method 200 (outdated standard?)for Method 200 (outdated standard?)

TNMOC concentrations have gone down TNMOC concentrations have gone down since the PAMS program was stated in since the PAMS program was stated in 19941994

0

0.5

1

1.5

2

2.5

3

1990 1991 1992 1993 1994 1995 1996

Year

PPB

Statewide Benzene Inventory Estimate: On-road Mobile Sources

0

10

20

30

40

50

60

70

1990

1991

1992

1993

1994

1995

1996

Year

Tons

-Ben

zene

/Day

Cal

iforn

ia P

hase

1, W

inte

r Oxy

gena

tes.

Cle

an D

iese

l.

Fede

ral P

hase

1 (s

elec

ted

area

s)..

Cal

iforn

ia P

hase

2 (p

roje

cted

).

Comparison of TNMOC for 1999 PAMS Season

Method 12-PDFID compared with Method 200-Sum of All1

-60

-40

-20

0

20

40

60

80

100

120

0 100 200 300 400 500 600 700 800 900 1000

Concentration

Per

cen

t D

iffe

ren

ce w

/r/t

PD

FID

1) Percent Difference = 100* (Method 12 - Method 200) / Method 12

ConclusionsConclusions A lot of data has been collected over the last A lot of data has been collected over the last

seven years with the 2000 season having the seven years with the 2000 season having the most extensive networkmost extensive network

With understanding of the data availability With understanding of the data availability and monitoring issues there is an and monitoring issues there is an opportunity for data users to better utilize opportunity for data users to better utilize PAMS dataPAMS data

Data users and monitoring staff need to Data users and monitoring staff need to collaborate on method sensitivity collaborate on method sensitivity

Web Sites of InterestWeb Sites of Interest

www.arb.ca.gov/aaqm/hcarbons.htmwww.arb.ca.gov/aaqm/hcarbons.htm

www.epa.gov/oar/oaqps/pams/www.epa.gov/oar/oaqps/pams/

www.epa.gov/oar/oaqps/pams/docs.htmlwww.epa.gov/oar/oaqps/pams/docs.html

www.arb.ca.gov/aaqm/toxics.htmwww.arb.ca.gov/aaqm/toxics.htm