Item No. __11b_supp_________
Meeting Date: October 25, 2022
Part 150 Noise and Land Use
Compatibility Study Briefing
October 25, 2022

                   Part 150 Overview
•  Code of Federal Regulations 14 (CFR 14) Part 150 – FAA established
study guidelines
•  Airports must follow those guidelines to obtain FAA Airport
Improvement Program (AIP) grant funding for abatement and mitigation
projects
•  Part 150s focus on airport noise and land use incompatibilities within
the 65 Day/Night Level (DNL) contour
•  Updated 65 DNL noise contours are the required outcome of a Part 150
•  FAA-approved mitigation measures become eligible for AIP funding at
80%

               DNL Noise Contour
•  Day Night Level (DNL) – annual average of noise from aircraft operating at SEA
•  Contours must be produced using the FAA-required Aircraft Environmental Design
Tool (AEDT)
•  65 DNL is the FAA-required metric and level
•  Contours are depictions of the cumulative impacts of aircraft noise, and must be
reviewed and approved by the FAA
•  FAA will not allow the use of noise monitoring data to assess impacts
•  The 65 DNL contour is the basis for land use analysis in the Part 150
•  Current and future noise impacts will be assessed


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              SEA 2018 DNL Contour

S 240th St                                                                                     S 100th St






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             Part 150 Land Use Planning
•  Identify noise incompatibilities within surrounding communities - below
65 DNL is compatible with all uses
•  Incompatible land uses at or above 65 DNL:
– Residential
– Schools
– Places of worship
– Hospitals
– Nursing homes
– Daycare facilities with licensed educators
•  Evaluate new potential noise abatement initiatives
•  Evaluate ongoing programs from past Part 150 Studies
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                SEA Part 150 Studies
• Initial study completed in
1985
• Updates
– 1992
– 2002
– 2014
• Extensive public
involvement

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       2014 Part 150 Study Record of Approval
– Noise Mitigation
• Updated noise remedy boundary
• Continuation of single-family sound
insulation
• New Condominium sound insulation
• New Apartment sound insulation
• Continuation of School Sound
Insulation Program
• Voluntary acquisition of residential in 3rd
runway South Approach Transition Zone
(ATZ)
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       2014 Part 150 Study Record of Approval
– Noise Abatement
• Continuation of Aircraft Maintenance
Run-up restrictions
• Continuation of the Fly Quiet Program
including monitoring noise abatement
procedures in place
• Ongoing monitoring of the Noise Abatement Corridors
• Evaluate and Upgrade the Noise Monitoring System
• Continue to operate the Noise Programs Office

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          New SEA Part 150 Study Update
• Consulting firm will be hired to lead the study and provide
technical expertise
• Finalizing the initial consultant scope
– Detailed project scope will be developed with chosen consultant and
presented to the Commission for input
• Consultant procurement finalized by mid year 2023
• Study development and data collection late 2023
• Full public study outreach anticipated early 2024
• Multi-year study that may take 4-7 years to complete
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         Commission Project Authorization
November 8th
• $1M – authorized in 2022
• $6M – this request to fully fund the project
• Authorization to procure consultant and execute contract


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