COMMISSION 
AGENDA MEMORANDUM                        Item No.          7a 
BRIEFING ITEM                             Date of Meeting      February 25, 2020 
DATE:     February 18, 2020 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Elizabeth Leavitt, Senior Director Engineering, Environment & Sustainability 
Arlyn Purcell, Director Aviation Environment & Sustainability 
Stan Shepherd, Manager, Airport Noise Programs 
SUBJECT:  Noise Programs Briefing 
EXECUTIVE SUMMARY 
This briefing is intended to inform the Commission about (1) the ongoing airport sound
insulation and other noise programs and (2) the concept of accelerating sound insulation not
currently in the 5-year Capital Improvement Program (CIP) but approved through the 2014 Part
150 Study update.  Acceleration would provide the community with noise reduction benefits
sooner than current funding and staffing rates allow but would require funding without a
guarantee of federal reimbursement.  If the Commission decides to move forward with
acceleration, the work already planned for 2020 would continue, and staff would also start
acceleration planning including identifying staff organization  and  program structure and
developing cost estimates. These early tasks would require consultant assistance. In 2020 there
would be a need to hire one additional Noise Program Manager and one additional AVPMG
Project Manager to begin implementation planning. Additional staffing would be assessed for
inclusion in the 2021 budget. 
BACKGROUND 
Code of Federal Regulations (CFR) Title 14, Part 150 governs Airport Noise Compatibility
Planning. Part 150 describes the processes by which airports identify and reduce exposure of
communities to airport noise. The completion of a Part 150 study and FAA approval of the
Noise Compatibility Program qualify noise mitigation measures, including sound insulation, for
federal funding. 
The Port Commission established Sea-Tac Airport's Part 150 noise mitigation program in 1985
as one of the first voluntary airport noise mitigation programs in the country. The original
sound insulation program was based on an estimate of the year 2000 noise impacts and 
included approximately 10,000 homes as potentially eligible. 
Since 1985, the Port has sound insulated approximately 9,400 homes at an approximate cost of
$300 million. The Port also has provided funding to help sound insulate noise impacted schools

Template revised April 12, 2018.

COMMISSION AGENDA  Briefing Item No. __7a__                             Page 2 of 4 
Meeting Date: February 25, 2020 
at an approximate cost to date of $70 million.  The Port also acquired and relocated residents
from approximately 1,828 homes for noise and 3rd runway construction at an approximate cost
of $100 million. 
In 2014, the FAA approved the most recent Part 150 update, which was a culmination of several
years of land use studies and public involvement. The Part 150 evaluated the current noise
impacts on the community and concluded that the contours showing average cumulative noise
levels had decreased from previous years, based primarily on the utilization of predominantly
newer, quieter aircraft within the fleet mix. Due to the reduction in noise, the FAA required
that Sea-Tac Airport redraw its noise remedy boundary to reflect the smaller noise footprint. 
The current noise remedy boundary encompasses approximately 3,771 residential units 
(including apartments, condominiums, and single-family homes) of which approximately 1,298 
residential units have not been sound insulated by the Port. For the remaining 1,298 residential
units, Port staff and consultants evaluated additional criteria including the date built and
structure type. Based on that evaluation, approximately 1,176 residential units are potentially
eligible.
Due to current FAA Airport Improvement Program (AIP) grant funding limitations, Port staffing
resources, and airport business priorities, the airport has made progress on implementation of
the Part 150 approved mitigation measures, but many residences remain to be treated.
Remaining sound insulation and acquisition projects include: 
Continued sound insulation for single-family homes  140 (As of 2/4/2020) 
Continued sound insulation for condominiums  3 complexes / 133 units 
Future sound insulation of apartment complexes  18 complexes / 903 units 
Future sound insulation of places of worship  7 structures 
Future voluntary acquisition of residential units in the South Approach Transition Zone  
approximately 16 homes and 6 apartment complexes 

Today's briefingwill update Commission on the status of each measure and recommend
acceleration of the remaining proposed work that is not in the Port's 5-year CIP or the FAA's
Airport Improvement Program (AIP) grant funding plan. The estimated costs of sound insulation
under current practice range from $150 million to $259 million; the estimated costs of an
accelerated program range from $132 million to $227 million.  The cost estimate ranges are
wide because the program is at the concept stage.  Acceleration would provide benefits to the
Port including: reducing community noise impacts sooner at a potential lower overall cost
savings to the Port by completing projects in less time.  The challenges of accelerating include: 
staffing, logistic resources, and project funding. It is unlikely that the FAA could fully fund the 
accelerated program based on nationwide availability of discretionary AIP noise funding. Sound
insulation and acquisition projects are typically eligible for FAA reimbursement at later dates if

Template revised September 22, 2016.

COMMISSION AGENDA  Briefing Item No. __7a__                             Page 3 of 4 
Meeting Date: February 25, 2020 
funding becomes available.  The Port would need to determine how projects could be funded
upfront at risk of not receiving FAA AIP grants.
Risks 
There are several risks associated with accelerating the sound insulation program. FAA AIP
grant funding presents the greatest risk, as the timing and amount of available funding are not
known.
Noise program costs are incorporated into the airfield movement area cost center and
recovered from the airlines through landing fees.  Capital costs paid by AIP grants (and
Passenger Facility Charges) are excluded from the airline rate base.  Under the terms of the
airline lease agreement, capital projects with rate base capital costs of $10 million or more are
subject to airline disapproval through the majority-in-interest (MII) provisions.  In prior years,
the Port's approach has been to proceed with Noise program projects to the extent AIP grants
are available. The airlines have generally been supportive of this approach. Even though
accelerating the program may result in lower total construction costs, if the Port receives less
AIP grant funding, the airline rate base costs could be higher.  The Noise program projects
discussed above, will likely be subject to airline review through a MII vote. 
Other risks and challenges include: 
o  Scaling the program up and hiring staff for program management and oversight will take
time 
o Obtaining contractors in today's hot market can be challenging and costly 
o  Product availability  noise rated specialty products aren't widely available and often
have long lead order times 
o  Homeowner participation is not guaranteed 
o  All residential properties must pass a strict FAA required noise audit 

ATTACHMENTS TO THIS BRIEFING 
(1)   Presentation slides 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
July 10, 2018  The Commission authorized contracting for Sound Insulation Architect & Project
Oversight Consulting for Condominiums 
October 11, 2016  The Commission authorized contracting for Sound Insulation Architect &
Project Oversight Consulting Services and Job Order Contracting (JOC) for Single-Family Homes 


Template revised September 22, 2016.

COMMISSION AGENDA  Briefing Item No. __7a__                             Page 4 of 4 
Meeting Date: February 25, 2020 
October 22, 2013  Second Reading and Final Passage of Resolution No. 3683 concluding the
Federal Aviation Regulation (FAR) Part 150 Noise and Land Use Compatibility Study Update for
Seattle-Tacoma International Airport. 
October 8, 2013  First Reading of Resolution No. 3683 concluding the Federal Aviation
Regulation (FAR) Part 150 Noise and Land Use Compatibility Study Update for Seattle-Tacoma
International Airport. 
April 23, 2013  The Commission authorized contracting for Sound Insulation Consulting
Services and Job Order Contracting (JOC) for Single-Family Homes. 














Template revised September 22, 2016.