We published a Draft EIS under the State Environmental Policy Act in 2021 that evaluated three possible
sites for the OMF South facility. After a public comment period (engagement summary,
comment summary), the Sound Transit Board identified the South 336th Street site in
Federal Way as the preferred alternative in December 2021. To align federal and state processes, we are
now publishing a National Environmental Policy Act Draft/SEPA Supplemental Draft EIS (Draft EIS) that
evaluates these same alternatives. Based on its transit expertise and greater federal funding
opportunities, the Federal Transit Administration will be the lead federal agency. A joint NEPA/SEPA Final EIS
will follow in 2024.
Sound Transit is working toward an opening in 2032 but is also pursuing measures to advance the opening earlier (potentially 2030). If the Midway Landfill alternative is selected as the project to be built, the opening date would be between 2035 and 2037 depending on the subsurface construction design option. We
share an updated project schedule when we have more certainty.
We’ve continued the project’s design and engineering work since the 2021 publication of the SEPA Draft
EIS. We’ve evaluated the potential environmental impacts of several design refinements, in the Draft EIS
After you review the findings on the NEPA Draft/SEPA Supplemental Draft EIS, share your feedback with the
OMF South project team. All public comments provided on the SEPA Draft EIS in 2021 are still valid and do
not need to be resubmitted.
November 2016: Voter approval
Voters approved 118 miles of Link light rail, including two new OMFs—one in the north corridor and
another in the South Sound—to serve the growing light rail system.
Mid to late 2018: Initial community idea gathering and evaluation
After receiving community input during the early scoping outreach period in April 2018, Sound Transit
identified 24 potential OMF South sites for further analysis. After initial screening, we reduced the
number of potential sites to 20. We assessed these 20 sites with a robust list of evaluation criteria,
including project schedule, long-term facility planning, operational requirements, environmental
impacts, and engineering risks, among others.
February to April 2019: SEPA Scoping
Based on the results of the detailed screening, Sound Transit recommended six sites in Kent and Federal
Way for further consideration. The public had the opportunity to share their thoughts on the six
potential sites, as well as the OMF South project Purpose and Need Statement and environmental resources
to evaluate in the Draft Environmental Impact Statement, during the scoping comment period under the
State Environmental Policy Act.
May 2019: Sound Transit Board action
After reviewing community feedback gathered during scoping and the thorough evaluation on the the six
potential sites, the Sound Transit Board identified three sites for further study in the Draft EIS:
- Midway Landfill alternative
- South 336th Street alternative
- South 344th Street alternative
Summer 2019 to 2021: SEPA Draft EIS
Sound Transit prepared a Draft EIS under SEPA to share findings with tribes, agency and jurisdictional
partners, social service and cultural organizations, and the public. We published the SEPA Draft EIS in
2021 and held a public comment period (engagement summary,
December 2021: Sound Transit Board identified a preferred alternative
After the SEPA Draft EIS comment period, the Sound Transit Board considered the SEPA Draft EIS analysis
and comments received and then identified the South 336th Street site in Federal Way as the preferred
alternative, with all three sites still to be evaluated in a Final EIS.
December 2021 to July 2023: Project refinements
After the Sound Transit Board identified the South 336th Street site in Federal Way as the preferred
alternative, we completed additional fieldwork activities and environmental analysis.
Additional site refinements were made to the preferred and South 334th Street alternatives.
July to August 2023: NEPA Scoping
After the Federal Transit Administration became the lead agency for the OMF South project, both the
Federal Transit Administration and Sound Transit held a scoping comment period under NEPA
for comments in addition to those received during SEPA scoping.
We are here: Draft EIS
To align the federal and state processes, the Federal Transit Administration (FTA) and Sound Transit
published a NEPA Draft/SEPA Supplemental Draft EIS that evaluates the same three alternatives as the
2021 SEPA Draft EIS. FTA is the lead
agency under NEPA and Sound Transit is the lead agency under SEPA. This additional review is to support
federal approvals, federal funding and assess project design changes. The findings from the EIS are
shared with Tribes, agency and jurisdictional partners, and the public through a 45-day public comment
period. All public comments provided on the SEPA Draft EIS in 2021 remain valid and do not need to be
resubmitted. After receiving and considering public comments, FTA and Sound Transit will complete a
joint Final EIS before the Sound Transit Board selects the project to be built.