SAMP Public Comment Template

WTF?

The SAMP is the Sustainable Airport Master Plan (SAMP). It is 31 projects bundled together as a single permit to build the largest expansion in airport history.

To proceed, the Port of Seattle has created a Near-Term Projects Draft Environmental Impact Statement (DEIS) which must be approved according to State law.

There is a public comment period on the DEIS which is open until August 20, 2026.

To learn more about the SAMP and what it will mean for you, go here.

Why you should comment

Comment periods exist to give the public an opportunity to read a draft proposal of major construction (and demolition) projects and question possible harms, and possible mitigations, before they are allowed to proceed.

As commenter, consider yourself an editor of the DEIS. Your comments will be read by the people who wrote the DEIS, the people who will approve it, and anyone reviewing any subsequent appeal. Your job is to point out mistakes, find gaps, ask for more information where there isn’t enough, and question specific conclusions you think they got wrong. Your job is to make it a better, more complete review of the project. This is especially important because, if approved, the SAMP will be the largest expansion in airport history. And yet, the draft provides almost no mitigations for a third more new flights, noise, pollution, and other permanent community impacts!

How to use this guide

Focus on the Comment Ideas. You don’t have to be lengthy, just pick a few. Use your own words–you may think of something no one else has– duplicating what anyone else writes is wasted effort. Do talk about how the issue affects you and your specific neighborhood.

Encourage the Port to work with local jurisdictions to develop a long term plan that will provide permanent, specific, and substantial mitigation plans for your community.

Send in your comment by Thursday, August 20, 2026, 5:00 PM:
web: sea-samp.com/get-involved
email: samp@portseattle.org (Mr. Steve Rybolt, Port of Seattle, AV Environment and Sustainability)

The Comment Ideas

We’ve broken these into three main themes:

• Segmentation
• The Greater Good Argument
• Outdated standards

Use the links next to each item to study an idea in more detail.

Each item ends with a Ask. That is the important part! You’re an editor. A good comment points out where the document is insufficient and names where it needs further study.

A specific Ask is what separates a comment from a complaint.

Segmentation

The SAMP minimizes project impacts by breaking components into small pieces by time and place. This strategy avoids consideration of its full impacts.

1. Not enough detail. The DEIS describes 31 projects at roughly 10% design. You cannot measure ongoing impacts of any major construction project from a drawing you cannot see. In fact, the Port has not even drawn any of it yet! Ask: finish the design — to at least 30% — and re-issue the analysis for public review before any project is permitted. At 10% design the EIS cannot support its own conclusions. (More from STNI: the 31 projects by the numbers)
2. Demolition with no detail. Typically, demolition requires separate permitting. To construct the SAMP, at least ten existing structures are slated for removal–including fuel storage–some of them beyond the airport’s own property line, and with no analysis. Previous redevelopments, like the North Satellite Modernization Project have demonstrated significant problems with preexisting soil contamination. Ask: Information on each demolition site and its potential impacts on surrounding communities should be provided before any permits are issued — how it’s done, where the debris and any hazardous material go — including the buildings that sit outside the AAA.
3. Noise: The study area does not match the impact area. The 2024 Part 150 study area is limited to the current DNL65, which has been reduced by more than half since 2013. Despite promises that ‘SEPA would be better’, noise impacts are being evaluated in exactly the same manner as the weak federal standards. Ask: use the State’s own RCW 53.54 noise boundary as the baseline for future noise migitation and abatement analyses.
4. Air: The study area does not match the impact area. In terms of air quality the study area is limited to the AAA — the airfield and construction. Despite promises that ‘SEPA would be better’, this is exactly the same as the weak federal standards. Ask: use the Port’s own Century Agenda as the target: a reduction of aircraft emissions by 25% from 2012 levels.
5. Water: The study area does not match the impact area. The study assumes that water quality testing on the airfield will adequately capture impacts throughout the watersheds — despite the fact that the AAA is a primary source for several basin plans: Des Moines Creek, Miller Creek, Walker Creek. High levels of PFAS (forever chemicals) have already been detected on the plateau. Ask: An updated, permanent monitoring system, including tests for forever chemicals, should be activated for all main watersheds within the APE.
6. The build-out already done doesn’t get counted. The Third Runway and everything built since 2008 are folded into “existing conditions”. This bakes in those previous impacts with no accountability. Ask: count the Third Runway and every project built since 2008 in the cumulative analysis, not as part of the baseline, and quantify what each one added on top of everything proposed now. (More from STNI: individual vs. cumulative)
7. Build-out within the terminal is not accounted for as added capacity. Billion dollar projects such as the 2017 Baggage Optimization are acknowledged as significant contributors to increased throughput, but appear nowhere in the DEIS. Ask: A new, more realistic analysis should be done which includes throughout improvements from improvements in the terminal.
8. Lack of project oversight. The SAMP assumes that all work will be conducted using best practice management. However, recent projects such as the North Satellite uncovered preexisting issues with bad soil that should have been caught ahead of time. Severe cost overruns and engineering missteps have been the rule more than the exception, including the International Arrivals Facility. These systemic issues go back to the Third Runway. It therefore must be assumed that similar issues will be the case with the SAMP. Ask: An analysis of contracting and management oversight should be conducted before permits for 31 new projects should be allowed to proceed.
9. Phase 2 is being kept off the table. The Long-Term Projects — the second half of the SAMP, discussed in 2016 — were renamed a “long-term vision,” that is “unknowable beyond five years” and thus allowed to fall outside this review. Ask: study the Long-Term Projects together with these Near-Term Projects. They serve the same expansion and should be reviewed as one. (More from STNI: the construction never ends)
10. SR-509 was permitted separately. The highway work that feeds traffic and capacity to the airport was reviewed and approved separately by the state in 2003 and 2018 — long before the current DEIS. Previously versions of both SR-509 and the Long-Term Projects indicate further expansion at the south entrance has already been planned. Ask: a combined analysis should be performed that considers SR-509 and the SAMP, including the Long-Term Projects as the single system they are — traffic, capacity, and stormwater loading on the same creeks — instead of two separate reviews.
11. The Port’s own authority to limit night flights is never analyzed as an alternative. Under 14 CFR Part 161, the Port — not the FAA — holds the authority to study and potentially impose restrictions on nighttime operations. Ask: analyze a Part 161 restriction on operations in the 10pm–7am window as a distinct alternative, independent of the Action/No-Action choice, and disclose whatever internal analysis — if any — the Port has already done on its own authority to pursue one.
12. The DEIS never asks whether the growth has to happen this way. The Port’s own forecasting documents that airlines have voluntarily diverted evening flights to nearby airports and brought them back the next morning — a demand-management move the Port never systematically studied. It fails to consider the role it plays in inducing new capacity — especially at shoulder periods. Ask: Analyze demand-management alternatives — including an expanded Fly Quiet program for 10pm-7am hours and terminal design as genuine alternatives to unmanaged growth, the same way SEPA requires any other reasonable alternative to be studied.

The Greater Good Argument

The Port portrays the project benefits wide and its impacts narrow. The airport is worth $22.5 billion “to the region” — the whole county and state — but the harms are evaluated and portrayed as close to the 2,500 acre fence line as possible.

1. The economic case has no foundation. Appendix K, Socioeconomics, claims job and tax benefits that are wildly inaccurate. Ask: an independent socioeconomic study with properly sourced numbers that separates temporary construction jobs from permanent ones and shows the net effect on each neighbor city over time — not region-wide. (More from STNI: Appendix K socioeconomics)
2. The airport is a net drain on its neighbor cities. The airport creates numerous unfunded mandates for surrounding cities, including both direct and indirect costs. The surrounding cities cover the difference. Ask: tabulate the true cost of tree replacement, FAA mandates such as bird deterrence, unrecovered tax base from property buyouts, loss of economic development opportunities, public safety in fence-line communities. Evaluate the airport’s true cost to adjacent cities, not county-wide. (More from STNI: the cost/benefit analysis)
3. Kids and schools. Schools under the flight path are among the lowest-performing in both King County and the State. The DEIS asserts these projects will not affect educational attainment, without acknowledging that they have and thus those impacts will only increase. The Port’s analysis considers noise as the only driver of negative impacts on student performance. We cannot address root causes until we consider drivers beyond the DNL65. Ask: Honestly study objective mitigation opportunities to school quality, neighborhood desirability and reinvestment beyond sound insulation. (More from STNI: don’t reinvent the wheel)

Outdated standards

The DEIS relies heavily on standards the Port itself has acknowledged are insufficient, but uses those standards to avoid providing more reasonable mitigations. This is especially egregious given that the DEIS is a process they, not the FAA, control, and one they promised would be better.

1. Noise. The current DNL65 system, measures individual noise events with a flawed A-Weighting, then averages the entire whole day (and night) of noise impacts into a single number which will always read as “not significant.” Ask: re-evaluate the noise portion of the SAMP using the supplemental metrics option of Part 150, with Z-Weighted (unfiltered) measurements and special emphasis on the gap between night-time flights and their effect on sleep disturbance. (More from STNI: DNL65 for dummies · the Sleepy Time penalty)
2. Air quality. The DEIS admits every major pollutant goes up, then says none of it crosses a significance threshold. Ask: produce a cumulative air-quality analysis that adds the emissions up across all projects and over time against health-based limits — not a project-by-project check.
3. Transportation. The SAMP relies heavily on traffic and transit data from 2022–before either system, let alone the airport had recovered from COVID-19. Recently, both Metro and Sound Transit have made major changes to their services to/from the airport. Ask: provide a fresh analysis based on current traffic and transit service.
4. Water. Stormwater and PFAS contamination are checked against standards that were already too weak, and tested at the pipe rather than in the creeks people live near. Ask: monitor in the creeks themselves, not just at the discharge pipes; set an enforceable PFAS cleanup standard; and give the downstream cities a formal monitoring role in water they drink and fish. (More from STNI: the PFAS standard delayed to 2031)
5. Fifty-year-old land-use guidance offers no way to make communities whole. What has never existed is a mechanism to evaluate the holistic impacts to surrounding cities for housing capacity removed in order to accommodate FAA Density Guidelines. Ask: require the SAMP to identify, by parcel, how much residential capacity in each host and neighbor city has been removed from play by noise-compatibility standards since 1976, and require an economic offset — including options such as cash, land swaps, and GMA target credits.

Right of inspection

Given both the scale of these projects, the long-term consequences, the lack of detail in any of the projects, the Port’s ongoing and historic issues with bad soil, tree loss, and water quality, coupled to the fact that it self-permits, the surrounding cities must be afforded the right to inspect the work before ground is broken and at reason intervals during the lifecycle of all 31 projects. (More from STNI: the IAF cost overruns and PFAS settlement)