Portland Air Toxics Baseline Monitoring Study
Detailed Work-Plan
1. Basis and Rationale
This work plan is to perform a comprehensive air quality monitoring study of toxic air
pollutants in the Portland area for one year. This study will build on earlier technical studies
of air toxics in the Portland area conducted by DEQ and EPA since 2005. This includes, a
ground-breaking modeling study conducted using data from 1999, development of health
benchmarks with the help of a science advisory committee, a comprehensive monitoring
study in 2005, a highly refined emission inventory for 2005 developed with the help of a
broad-based advisory committee, evaluation of data from EPA’s Toxic Release Inventory, a
multi-year monitoring study at Harriett Tubman Elementary School, an exposure and risk
assessment conducted by EPA using data from 2005, ongoing monitoring of air toxics at one
location in North Portland, meteorological monitoring at four locations, and a sophisticated
dispersion modeling study of air toxics concentrations in 2017. This study will allow us to
determine current concentrations of air toxics, track trends since 2005, evaluate short term
and seasonal variations in concentrations, check the performance of the dispersion model,
help understand the causes of air toxics concentrations, and establish a baseline for analysis
of potential future reductions in emissions. This will contribute to the scientific basis for
ensuring that public health is not at significant risk from air toxics.
2. Technical Approach
DEQ proposes to conduct air toxics monitoring at approximately 8 sites in the Portland area
for one year.DEQ will select monitoring sites, analytical methods and pollutants to monitor
using the 2017 dispersion modeling study. As an example, a monitoring site located in an
older residential neighborhood where wood is the predominant source of heat is a likely
candidate for a monitor. Likewise, a monitor located very close to a roadway is another
likely candidate.
a. Sampling Network. The table below contains preliminary suggestions for monitoring
sites, identified solely for the purpose of scoping the project. Final determinations will
be made after funding is secure and logistical and resource issues are addressed.
Toxic Pollutant
Focus Area
Location
Hillsboro
Gresham
Target Pollutants
VOC
Method
TO-15
SVOC
TO-13
Residential Wood
Combustion, Lawn
& Garden
VOC
TO-15
Residential Wood
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Near major roadway
(within 50 m)
Oregon City
I-205/OR-213
Carus
Northwest Portland
North Portland
SE Portland
(NCORE site)
Mn = Manganese
As = Arsenic
Cd= Cadmium
SVOC
TO-13
MSATs
TO-15
As
Cr+6
VOC
IO-3.5 (PM10)
CARB Method 039
TO-15
SVOC
TO-13
Formaldehyde
Acetaldehyde
Mn, As, Cd
Cr+6
Benzene
TO-11
Mn, As, Cd
Cr+6
PAH
Naphthalene
IO-3.5 (PM10)
CARB Method 039
TO-13
IO-3.5 (PM10)
CARB Method 039
TO-15
Combustion, Lawn
& Garden
On-road mobile
Residential Wood
Combustion, Lawn
& Garden
Secondary
formation
Point source
Point source
Residential Wood
Combustion
Cr+6 = Chromium 6
PAH = Polycyclic Aromatic Hydrocarbons
S/VOC = Volatile Organic Compounds
MSAT =Mobile source air toxics
b. Sampling Methods. All methods will follow the guidelines set forth in the EPA Technical
Assistance Documents for air toxics sampling.
i. Sampling shelters and decks. Sites requiring gas sampling will have a temperature
controlled shelter. Metals sampling will be done from a sampling platform
adjacent to the shelter with the sampler inlet approximately 2 meters above the
ground.
ii. Sampling probes. All gas sampling will be done using a standard glass manifold.
Sample residency times will be less than 20 seconds. All tubing will be glass or inert
Teflon.
iii. Carbonyls. Samples will be collected using DNPH cartridges operating at a flow of 1
lpm. The sample gas will flow through a heated ozone scrubber to remove that gas
from the sample stream.
iv. VOC. Sub-atmospheric whole air samples will be collected using stainless steel
canisters with a passivated inner lining and an Entek sampler. The canisters will be
typically 6.0 or 1.7 liters in volume.
v. Semi-VOC. Samples for semi-volatile compounds will be collected using a Tisch PUF
sampler. The sample media is a glass fiber filter followed by sandwich of polyurethane foam (PUF), XAD resin, and PUF. The sample flow rate is 8 cfm.
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vi.
vii.
PM10 Metals. Samples for metals will be collected using a federal reference
method PM10 High-Volume sampler with a quartz filter. Sample air flow will be 40
cfm.
Hexavalent Chrome. Samples for hexavalent chromium analysis are collected on 37
mm bicarbonate impregnated ashless cellulose filters at a flow rate of 15 lpm. A
modified R&P model 2000 FRM is used as the sampler.
c. Sampling Frequency. Samples will be collected every 6th day following the national EPA
schedule. Duplicates will be collected for each method at the Portland National Air
Toxics Trends Site.
d. Quality Assurance. A quality assurance project plan will be developed and implemented
for this project. Standard QA procedures will be followed regarding the collection and
analysis of samples and the reporting of results.
e. Data Reporting. Samples will be processed and analyzed at the DEQ Laboratory where
they will be tracked and reported by the Lab Information Management System (LIMS).
All final data will be available from the Agency database – LASAR. Hard copies of the
final reports will be archive at the DEQ Lab.
3. Data Analysis
a. Analytical Methods
i. Carbonyls – TO-11. Method TO-11 is used for the analysis of ketones and
aldehydes in air. The method consists of the analysis of the 2,4Dinitrophenylhydrazine (DNPH) derivatives of carbonyl compounds in ambient air,
by high performance liquid chromatography (HPLC) with ultraviolet (UV)
detection. The analysis is performed on an Acetonitrile extract of the cartridge.
ii. VOC – TO-15. Method TO-15 is used for the determination of Volatile Organic
Compounds (VOC’s) in ambient air from specially prepared canisters by Gas
Chromatography/Mass Spectrometry analysis. This method is applicable to specific
VOC's that have been tested and determined to be stable when stored in
pressurized and sub-atmospheric pressure canisters.
iii. Semi- VOC – TO-13A/ASTM D 6209. This is the method for identifying and
quantifying Polycyclic Aromatic Hydrocarbons (PAH's) in air, per ASTM Method D
6209-98 following soxhlet extraction. The samples are prepared for Gas
Chromatography/Mass Spectrometry (GC/MS) analysis by extracting the
PUF/XAD/PUF cartridge and glass-fiber filter as received with a Soxhlet extractor.
The extract is concentrated and transferred to an autosampler vial, to which an
internal standard solution is added. The extract is analyzed by GC/MS in the
Selected Ion Monitoring (SIM) mode.
iv. PM10 metals – IO-3.5. This method is used for the analysis of air particulate
samples collected on PM10 High Volume quartz filters for the determination of 7
primary air toxics metals (As, Be, Cd, Cr, Pb, Mn, Ni) and 2 secondary air toxics
metals (Co, Se). The digest is analyzed by ICP-MS using the standard ICP-MS SOP.
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v.
The digestion procedure is a modified version of the California Air Resources Board
(CARB) SOP MLD061 revision 0.0.
Hexavalent Chrome. CARB Method 039 is used for the analysis of Total Suspended
Particulate (TSP) for hexavalent chromium.
b. Use of the Data
The data collected will be used to generate an annual average for each pollutant
monitored. The annual averages will be compared to the ambient benchmark
concentrations to determine which pollutants are above healthy levels. Variations in
annual averages throughout the region will be used to refine reduction strategies as
they are investigated and developed.
4. Community Collaboration & Outreach
DEQ has worked for many years with diverse stakeholders in the Portland area to
understand and reduce the risk from air toxics. This has ranged from collaboration with
organizations to formal advisory committees. Stakeholders include representatives from
neighborhoods, public interest organizations, government health and transportation
agencies and business.
5. Environmental Results: Outcomes, Outputs, Performance Measures
a. The study will produce measured ambient concentrations of the toxic air pollutants that
pose the highest risk to Portland area residents: manganese, arsenic, hexavalent
chromium, cadmium, benzene, acetaldehyde, formaldehyde, naphthalene, and
polycyclic aromatic hydrocarbons. Sampling will occur over a 12 month period and will
capture daily, monthly, and seasonal trends in air toxics, as well as be used to calculate
annual average concentrations. DEQ hopes to also include some analysis of hourly
concentrations to assess variation throughout the day. The sampling methods will also
be able to capture many other volatile, semi-volatile, metal, and carbonyl pollutants as
well.
b. The outcomes for this project are:
i. The monitoring data will be used to calculate annual average concentrations which
can be compared to benchmarks of acceptable risk, allowing DEQ to better
characterize the current risk to the public. The monitoring data will help build the
scientific foundation for assessing air toxics in the Portland metro area, and also
provide a better means to monitor emission reduction progress goals.
ii. The monitoring data will also provide basic science information to better
understand and reduce air toxics risk.
6. Detailed Budget Narrative
Grant funds will be used to purchase equipment and support limited duration staff to
maintain the monitoring network and conduct the laboratory analysis. DEQ estimates that
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the grant can support 8 monitoring locations, monitoring for a combination of PM10
metals, hexavalent chromium, carbonyl, volatile, and semi-volatile compounds at different
sites. Since DEQ’s existing laboratory staff is not sufficient to conduct this study, DEQ would
hire limited-duration staff for 12 months. After the study is complete, DEQ would use the
equipment to replace old monitors or to provide spare parts at existing air toxics sites. DEQ
would not need or continue the limited duration staff beyond the 12 month study.
Salary:
Natural Resources Specialist 2 - step 2, (12 months)
Natural Resources Specialist 3 – step 2, (12 months)
Chemist 3 – step 2, (12 months)
Chemist 2 – step 2, (12 months)
Chemist 2 – step 2, (12 months)
Sub-total Salaries
$40,632
$46,848
$49,080
$44,712
$44,712
$225,984
Fringe Benefits
$125,461
Services & Supplies
$103,621
Capital Outlay – monitoring equipment for:
PM 10 metals
Semi-volatiles
Volatile Organic Compounds
Met Systems
Monitoring shelters
Sub-total Capital Outlay
$ 10,000
$ 34,000
$ 78,000
$ 16,000
$ 89,000
$227,000
Indirect Costs
$ 67,934
Total Budget
$750,000
7. Leveraging
Recent DEQ technical work DEQ includes the most comprehensive emissions inventory and
dispersion model ever developed for the Portland area. Integrating GIS layers for land use
and transportation zones allow for source allocation in the sub-census block level of
refinement. The results of this technical work provide DEQ with invaluable information for
siting monitors. The monitoring results, in turn, will provide a means to validate the model.
The following existing monitors complement this proposal:

DEQ will continue to operate our federally funded long term National Air Toxics
Trends site at North Roselawn. Data from this site will be incorporated with data
collected in this study.
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

DEQ will continue to operate our NCORE (multi-pollutant for gases and PM) site in SE
Portland. Data from this site will be incorporated with data collected in this study.
DEQ currently operates 4 meteorological monitoring systems in the metro area that
will provide data to supplement this study.
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