PORT OF SEATTLE 
MEMORANDUM 
COMMISSION AGENDA               Item No.      7a 
STAFF BRIEFING              Date of Meeting  December 4, 2012 

DATE:    November 27, 2012 
TO:     Tay Yoshitani, Chief Executive Officer 
FROM:    Stephanie Jones Stebbins, Director, Seaport Environment and Planning 
Janice Gedlund, Air Quality Program Manager 
Ellen Watson, Environmental Program Manager 
SUBJECT:  2011 Puget Sound Maritime Emissions Inventory 
SYNOPSIS: 
The 2011 Puget Sound Maritime Air Emissions Inventory (Inventory) was released by
the Puget Sound Maritime Air Forum (Forum) on October 30, 2012. The inventory
update quantifies maritime-related emissions for the calendar year 2011, and compares
the data against the 2005 baseline inventory. It also illustrates the effects of emission
reduction efforts undertaken by the Port of Seattle and others over the 2005  2011 time
period.  Pollutants inventoried  include diesel particulate matter, sulfur dioxides,
greenhouse gases and a number of other pollutants.  The data shows that maritimerelated
air pollution in the Puget Sound region has decreased as much as 40 percent,
depending on the sector and contaminant.
The 2011 Inventory revealed that Port of Seattle total emissions dropped for every
pollutant measured. The report looked at both absolute emissions, as well as normalized
emissions (emission rate based on a unit of 10,000 tonnes of cargo.) Emissions of diesel
particulate matter (DPM) were reduced 27% overall, and 34% per 10,000 tonnes of
cargo. Greenhouse gas emission declined by 5% overall and by 14% per 10,000 tonnes
of cargo.
Results of the 2011 Inventory will be used to refine and update the Northwest Ports Clean
Air Strategy (NWPCAS) and set long-term goals for 2020.
BACKGROUND: 
Overview 
The 2011 Inventory updates the 2005 baseline inventory which identified and quantified
pollutants emitted from maritime-related diesel equipment and alternatively fueled
equipment operating within the greater Puget Sound regional airshed. Similar to the 2005
inventory, the 2011 inventory quantifies annual marine diesel emissions and maritime-

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
November 27, 2012 
Page 2 of 5 
related activities associated with U.S. operations in a defined portion of the greater
Georgia Basin/Puget Sound International Airshed. This area spans approximately 140
miles south to north and 160 miles west to east, at its extremities. The geographical
domain used in the 2011 inventory is the same as the 2005 inventory and is referred to as
the greater Puget Sound airshed. 
The inventory provides scientific data and evaluation of emissions from marine-related
activities in the region in 2011 and compares those emissions to 2005. This study is
anticipated to improve understanding of the nature, location, and magnitude of emissions
from maritime-related operations, aid in planning and prioritizing future emission
reduction investments in the region, and to help evaluate the success of existing emission
reduction programs.
The Inventory was funded a total of $354,572 by the Forum a voluntary association of
private and public maritime organizations, ports, air agencies, environmental, public
health advocacy groups, and other parties with operational or regulatory responsibilities
related to the maritime industry. The Port of Seattle contributed $106,500 to this effort. 
Pollutants measured in the inventories include relevant U.S. Environmental Protection
Agency (EPA) criteria pollutants and precursors, including carbon monoxide, nitrogen
oxides, sulfur dioxides, volatile organic compounds and fine particulate matter, as well as
greenhouse gases, and diesel particulate matter.  The 2011 inventory update is an
activity-based inventory following a similar methodology as the 2005 baseline inventory.
Data was gathered for the following six major source categories associated with marine
sectors: 
Ocean-going vessels 
Harbor vessels 
Cargo-handling equipment 
Locomotives 
Heavy-duty trucks 
Fleet vehicles 
For 2011, the Port of Tacoma and the Port of Seattle looked at both total Port related
emissions in the airshed as well as "on port" emissions. We made this change toget a
better understanding of port-related emissions in the region. In 2005, we only looked at
"on-Port" emissions. Given community interest and focus on port emissions in the
region, we felt it was important to look more broadly at our emissions. This change,
coupled with improvements in emissions modeling, resulted in some differences in the
methodologies between 2011 and 2005. Where there were differences, the 2005
emissions were updated using the same modeling  parameters to ensure a direct
comparison between the baseline year and 2011. The inventory also compared TEU and
tonnage in 2005 and 2011 to normalize emissions based on level of throughput. Other

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
November 27, 2012 
Page 3 of 5 
Maritime Emission Inventories, such as those done at Ports of LA and Long Beach use a
similar approach. 
Puget Sound-wide Results 
Much of the clean air progress is due to significant, voluntary investments of the
maritime industry and government agencies in cleaner technology, cleaner fuels and more
efficient systems of operation. Mandatory engine and fuel standards have also spurred
adoption of newer engines and cleaner fuels. Some of the decrease can also be attributed
to fewer ship calls and less cargo resulting from a sluggish economy. 
Emissions in the Puget Sound airshed dropped since 2005 from the following pollutants: 
Nitrogen oxides: reduced 14 percent 
Volatile organic compounds: reduced 40 percent 
Sulfur oxides: reduced 14 percent 
Particulate matter (PM10): reduced 16 percent 
Fine particulate matter (PM2.5): reduced 16 percent 
Diesel particulate matter: reduced 16 percent 
Carbon dioxide: reduced 5 percent 
Overall, Puget Sound airshed emissions fell for most sources since 2005. DPM emissions
are summarized below: 
Ocean-going vessels: reduced 16 percent 
Harbor vessels: increased 7 percent 
Locomotives: reduced 24 percent 
Cargo-handling equipment: reduced 40 percent 
Heavy-duty vehicles: reduced 52 percent 
Fleet vehicles: reduced 47 percent 
In the harbor vessels sector, this includes ferries, tugs, fishing and recreational boats,
some categories of pollutants increased. This is likely due to a 12 percent increase in
vessel traffic, as well as an increase in the use of larger engines, which have higher
emissions. 
Port of Seattle Results 
Total Port of Seattle emissions within the airshed dropped since 2005 from the following
pollutants: 
Nitrogen oxides: reduced 24 percent 
Volatile organic compounds: reduced 16 percent 
Sulfur oxides: reduced 21 percent 
Particulate matter (PM10): reduced 27 percent 
Fine particulate matter (PM2.5): reduced 27 percent 
Diesel particulate matter: reduced 27 percent 
Carbon dioxide: reduced 5 percent

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
November 27, 2012 
Page 4 of 5 

Data was gathered for the following six major source categories associated with marine
sectors: At the Port of Seattle we saw the following absolute reductions in DPM: 
Ocean-going vessels transit, 21% reduction 
Ocean-going vessels hoteling, 34% reduction 
Harbor vessels: 27% reduction 
Cargo-handling equipment: 39% reduction 
Trucks; 53% reduction 
Rail operations. 14% reduction 
Green House Gas Emissions also declined by 5% at the Port of Seattle. 
Next Steps 
The original 2005 Inventory was the foundation on which the NWPCAS was developed
in 2007. The NWPCAS was a collaborative effort by the Port of Tacoma, the Port of
Seattle and Port Metro Vancouver (BC), along with the Puget Sound Clean Air Agency,
the EPA, the Washington State Department of Ecology and Environment Canada.
Emission reduction initiatives and potential actions were defined in the Strategy and
emission reduction goals were set, based to a great extent, on the 2005 Inventory. The
Strategy has helped the ports to achieve reduced at-berth emissions for ocean going
vessels through the use of low-sulfur fuels and shore power; reduced cargo-handling
equipment emissions, reduced on-terminal truck emissions through engine retrofits and
scrap-and-replace incentive programs, and reduced locomotive emissions through
application of idle-reduction technologies.
Marine diesel engines, like all diesel engines, are significant generators of fine particles
and toxic emissions. Exposure to these pollutants can contribute to increased rates of
lung cancer, chronic respiratory and cardiovascular disease, and other health effects.
Diesel emissions also contribute to acid deposition, climate change and impaired
visibility. Given the implications for public health and the environment, reducing and
minimizing diesel particulate matter (DPM) has been a top priority for the Port of Seattle,
and has been the primary focus of our emission reduction programs.
Results of the 2011 Inventory will be used to refine and update the NWPCAS and set
long-term goals for 2020. 
OTHER DOCUMENTS ASSOCIATED WITH THIS BRIEFING: 
Powerpoint presentation on results of the Inventory 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS: 
On February 9, 2005, the Commission adopted Resolution No. 3534, expressing
its commitment to Maritime Air Quality.

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
November 27, 2012 
Page 5 of 5 
On April 26, 2005, the Commission authorized joint development of the Puget
Sound Maritime Air Emissions Inventory and $500,000 for support and
implementation of the project. 
On February 16, 2007, the Commission passed a series of environmental motions
that required, in part, that staff present an air quality action plan for Commission
approval. 
On March 27, 2007, the Commission authorized the amendment of the existing
contract for the Air Emission Inventory in the amount of $25,000, and to receive
and spend supplemental funding for the Puget Sound Maritime Air Emissions
Inventory Project. 
On April 10, 2007, the Commission was briefed on the Puget Sound Maritime Air
Emissions Inventory Project. 
On August 25, 2009, the Commission received a Clean Air Update. 
On January 12, 2010, the Commission was briefed on the Seaport's Air Quality
Program. 
On December 7, 2010, the Commission was briefed on the Northwest Ports Clean
Air Strategy Implementation Status. 
On July 12, 2011, the Commission was briefed on the Northwest Ports Clean Air
Strategy 2010 Implementation Report and interim report on Accelerating Clean
Air Goals. 
On Feb 7, 2012, the Commission was briefed on the Northwest Ports Clean Air
Strategy draft recommendations on accelerating Seaport Clean Air Goals.