Item No. 7c_supp 
Meeting Date: January 22, 2019 
Slide 3 CORRECTED: January 25, 2019 
Sound Mitigation Briefing 
January 22, 2019 

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Part 150 Overview 
Code of Federal Regulations 14 (CFR14) Part 150  FAA established
guidelines 
Airports must follow to get federal grants for mitigation projects 
The focus of Part 150 is to address noise and land use incompatibilities 
Educate the public about the airport 
FAA Approved mitigation measures become eligible for AIP funding at
80% 

Part 150 is an airport noise and land use planning tool 
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Sea-Tac Part 150 
Original program began in 1985 
Completed 3 updates 
Last update completed in 2014 
Extensive public involvement 
Public workshops 
Highline Forum updates 
City council presentations 
Commission updates 
Technical Review Committee 
Sea-Tac airport has been mitigating for more than 30 years 
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DNL Noise Contour 
Day Night Level (DNL)  Annual cumulative average of noise emitted
from aircraft operating at Sea-Tac airport 
10 dB penalty for aircraft operating between 10pm and 7am 
Contours MUST be developed using the FAA Airport Environmental
Design Tool (AEDT) 
The FAA will not allow airports to use noise monitoring recorded
decibel levels for production of DNL contours 
Contours must be submitted to and approved by the FAA 
The 65 DNL Contour is the basis for land use analysis in the Part 150 
DNL contours are an annual cumulative depiction of aircraft noise 
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2018 65 DNL Noise Contour 


Contours shrank due to quieter aircraft in the fleet mix 
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Noise Remedy Boundary 


Noise Remedy Boundary is smaller due to shrinking noise contours 
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Part 150 Land Use Planning 
Identify noise incompatibilities within surrounding communities 
Below 65 DNL is compatible 
Non-compatible at or above 65 DNL 
Residential 
Schools 
Places of Worship 
Hospitals 
Nursing Homes 
Daycare facilities with licensed educators 
Part 150 identifies land use that is not compatible with airport noise 
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Sound Insulation 
No cost to the homeowners 
Port receives an "Avigation
Easement" in exchange for
the insulation 
Sound rated windows, doors,
& ventilation 

Sound insulation reduces interior noise levels to 45 dB or less 
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History of Noise Mitigation 
Sound Insulation 
Began in 1985 
Approximately 9,400 homes have been completed 
7 Highline Schools completed 
5 Condominium Complexes 246 units 
14 Buildings on the Highline College Campus 
Acquisition 
5 Mobile home parks, 359 mobile home units 
69 Homes north of the 3rd runway 
1,400 single family homes including 3rd runway acquisition 
Approximately $300 million spent on sound insulation / $100 million on noise related acquisition 
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Current Part 150 Recommendations 
Public workshops  numerous ideas were vetted 
Ideas were narrowed down to elements that were feasible
and allowable under Part 150 


All new programs must be within the new 65 DNL Contour 
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Single Family Sound Insulation 
Continuation of Single Family Sound Insulation 
Approximately 150 homes potentially eligible 
Potential cost of approximately $14.5 million 
Project was approved by Commission and construction
starts 1st quarter 2019 

Construction in Progress 
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Condominiums 
3 complexes comprised of 240
estimated units 
Potential cost of approximately $20
million (costs are being refined by
PMG) 
Begin project in 2019  1st complex 
FAA grant funded at 80% of eligible
costs 
Condominiums, 240 units 
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Apartment Sound Insulation 
18 buildings identified as potentially eligible 
Approximately 877 units 
Potential cost of $24 million 
FAA grant funded at 80% of eligible costs 
Part 150 recommended a feasibility study first 
Completed April 2016 
Begin project definition of 
pilot project of 1 building in 2022 
estimated cost of $2,300,000 
Apartment sound insulation, 877 units 
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Places of Worship Sound Insulation 
7 structures identified as potentially eligible 
Potential cost of $6.6 million 
P150 recommended a feasibility study first 
Completed April 2016 
Begin project definition of pilot project of 1 building in
2023  estimated cost of $1.1 million 

Places of worship insulation, 7 structures 
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Voluntary Purchase of Avigation Easements
For Mobile Homes On Private Land 
Estimated number of eligible parcels 88 
Potential cost of easements $462,000 
FAA grant funded at 80% of eligible costs 
Begin easement purchase 2021 


Mobile home avigation easement purchase, 88 parcels 
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Voluntary Home Acquisition Within The
Approach Transition Zone (ATZ) 
ATZ is an area 2500 feet off the end of the
Runway Protection Zone (RPZ) 
Approximately 16 Single Family Homes & 6
apartment buildings 
Estimated cost $11.5 million 
RPZ 
Begin Project 2022 
FAA grant funded at 80% of eligible costs               2
5
ATZ    0
0
f
e
e
t 
Residential voluntary acquisition in south ATZ 
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Schools 
MOA in place with Highline School District
(HSD), FAA, and the Port to sound insulate 
8 schools have been completed 
7 HSD schools remain to be sound insulated 
Des Moines Elementary currently under
construction 
Highline High School planning has started 

Highline School District, 7 schools 
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Thank You 

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