 As
an integral part of the Vision 2000 Air Quality Mitigation Program,
the Port of Oakland initiated an air quality and meteorological
monitoring program in West Oakland on April 22, 1997. The program
was designed to collect baseline data on particulate air pollution
in the West Oakland region prior to and during construction and
operation of the Port maritime development projects, and to help
evaluate the effectiveness of the mitigation projects. The Port
intends to continue tracking particulate and meteorological data
until April 2004.
The program measures Particulate Matter 10 (PM10)
and Particulate Matter 2.5 (PM2.5) concentrations at two locations
using dichotomous samplers. One sample location is in the vicinity
of Port facilities and construction activities, and another location
is in the West Oakland  residential
neighborhood east (downwind) of Port facilities. Meteorological
data (wind direction and speed) is also measured at the Port location.
The PM levels are then compared to state and federal air quality
standards and to other Bay Area cities monitored by the Bay Area
Air Quality Management District (BAAQMD). Fine particles (PM2.5) typically result from fuel combustion
from motor vehicles, power generation, and industrial facilities,
as well as from residential fireplaces and wood stoves. Coarser
particles (PM10 or larger) are generally emitted from combustion
sources, vehicles traveling on unpaved roads, construction activities,
and crushing and grinding operations, as well as windblown dust.
PM10 and PM2.5 are of concern to the public because the particles
are small enough to be inhaled into the human lung.
 The
West Oakland monitoring station is located downwind of the Port
station more than 65% of the time throughout the year. Given predominant
wind directions in the Bay Area, the Port and West Oakland neighborhood
stations are well positioned to assess impacts Port activities may
have on West Oakland communities. Particulate matter concentrations are highly influenced by wind
conditions. The long term (quarterly and annual) trends of the
data are studied to see if particulate levels at the Port and
West Oakland Residential sites follow regional (Bay Area) trends,
or if localized effects are noticed. Throughout the Vision 2000
construction project, the Port and Residential sites have followed
the general regional trends for particulate matter, that is the
data is statistically similar to other Bay Area station locations.
Annual trends at the Port and Residential sites
follow the general Bay Area annual trend. In a given year, if particulate
levels are high or low, all stations will generally follow the annual
increase or decrease. For example, PM10 and PM2.5 levels were high
in 1999 and 2001, and low in 2000 for all stations in the Bay Area.
PM2.5 is often used as an indicator or marker for the presence of
diesel emissions. The data collected from the past three years indicate
a general downward trend in PM2.5 levels throughout the Bay Area.
(No data is available from BAAQMD stations for PM2.5 prior to 1999).
The Port and Residential sites follow this general downward trend.
PM2.5 levels at both the Port and Residential sites exhibit a regional
influence, meaning that the levels are similar to levels throughout
the Bay Area. Bay Area wind patterns and activities at large have
more influence on PM2.5 levels than local sources. Both the Port
and Residential levels are below or equal to the calculated Bay
Area three-year average for PM2.5. Of the BAAQMD monitoring stations
included in this study, four stations are below and four are above
the Bay Area three-year average.
Results collected from the Bay Area monitoring stations have demonstrated
that PM10 levels, like PM2.5, are regionally influenced. The West
Oakland Residential site and the Port site follow the regional
influence trend as well as the Bay Area annual trends.
According to the PM10 data collected from the Bay Area air monitoring
stations included in this study, five stations are above the Bay
Area five-year average and six stations are below the average.
The Port site tends to have higher PM10 levels
than other monitoring stations within the Bay Area. However, the
data indicate that these particulates are not impacting the residential
community. The larger particles are too heavy to be transported
to nearby downwind communities.
For more information on this program, please contact Mr. Tim Leong,
Port Environmental Scientist in the Environmental Health and Safety
Compliance Division, at (510) 627-1537.
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