SEPA- State Environmental Policy Act

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The SEPA process is a Washington State requirement intended to ensure that state and local agencies consider the likely environmental consequences of a proposal before acting on the proposal.  All government decisions require environmental review, but may not be subject to procedural requirements under the Act.

When SEPA is Required

Many projects are exempt from SEPA requirements under either state law (WAC 197-11-800) or through local regulations (TMC 13.12.800).

The Most Common* SEPA Triggers
Work occurring within critical areas and/or on lands wholly or partly covered by water
Construction of residential structures – more than 20 dwelling units
Construction or demolition of a building – greater than 12,000 square feet
Construction of a parking lot – more than 40 vehicles
Fill or excavation – more than 500 cubic yards
Installation or removal of impervious tanks on industrial property – capacity of more than 60,000 gallons
Stormwater, water, & sewer utilities – more than 12 inches in diameter
Installation of wireless facilities – on a residence or school or within an area zoned residential
Construction of a wireless tower – 60 feet or taller or within a residential zone
Certain land use decisions – Rezone

SEPA Process

Submittal of SEPA materials in a separate land use application should occur at the time of building permit submittal (if there is no associated land use permit) or along with the application for an associated Major Land Use Decision. Additional materials may be requested, such as a geotechnical report, critical areas report, or a cultural resources assessment. A Planner can help you determine if additional materials are needed.

A completed Environmental Checklist is the form the City uses to gather information in order to make a SEPA determination.  Applicants are required to submit a checklist along with any required information for the associated building or land use permit.  Copies of the Environmental Checklist form are available at the Planning and Development Service Department, 747 Market Street, 3rd Floor and they are also located online:  A separate copy of the site plan, building elevations, and other required materials should be submitted.

All application materials must be submitted in electronic PDF format on compact disc (CD) or online at  See Electronic File Standards Tip Sheet

  • SEPA submittals for building permits will be reviewed for completeness before being taken in.
  • SEPA submittals associated with major Land Use Decisions can only be taken in concurrently with the associated Land Use application at the pre-application meeting. The Determination is issued with the Land Use Decision and the 14-day appeal periods run concurrently.
  • SEPAs associated with building permits take approximately 30 days to process and have a 21-day appeal period; building permits will not be issued until the SEPA process is complete.

Other Lead Agencies

If a Determination has already been issued for the project by a different lead agency, of if the project has previously been subject to NEPA (National Environmental Policy Act) a copy of that Determination along with the associated Environmental Checklist may satisfy the City’s SEPA requirement.

Other agencies include School Districts, Park Districts, State Agencies, County Agencies, Local Air Pollution Authorities, and the Port of Tacoma.

Other Lead Agencies, such as the Port of Tacoma, can issue SEPA Determinations for work within their jurisdiction.

Filling out the Environmental Checklist

Section A

  • It is helpful if the contact information for the person preparing the checklist is provided.
  • The project description should be thorough and not rely on other permit documents.
  • To the extent the requirements for SEPA (or “triggers”) are known they should be listed.
  • If you know of prior environmental review related to the proposal or the site, please inform BLUS staff. Part or all of that review may satisfy the City’s requirements.

Section B

  • Leave a wide right margin for staff to make notes.
  • The answer “not applicable” should be avoided and, when used, should include an explanation.
  • Please feel free to contact City Staff for assistance when answering questions about the Comprehensive Plan, zoning designations, historic status, and other related questions.
  • The checklist questions apply to all parts of the proposal, even if they are going to happen at different times or on different parcels.
  • When additional studies are required, they should be referenced in the checklist.

Signature Section

  • The checklist must be signed by the applicant and the processing fee must be included, for the submittal to be accepted.

Threshold Determination

Following review of the checklist and supporting information, the City will make a “Threshold Determination” for the proposal. There are three different types of Threshold Determinations:

  • DNS (Determination of Non-Significance) – the most common determination; this means that the proposal is not anticipated to have a significant impact on the environment.
  • MDNS (Mitigated Determination of Non-Significance) – means that impacts to the environment were identified while processing the Determination, but conditions have been included in the Determination and related land use and/or building permits that will mitigate the impact(s).

DS (Determination of Significance) – means that there will be probable significant adverse impacts to the environment which cannot be mitigated and an EIS (Environmental Impact Statement) must be prepared.  If it is anticipated that a project will result in an EIS, likely that the applicant will be contacted and asked to provide additional information.

Additional Reports

During the scoping meeting process, requests for additional reports may be identified.  The applicant may also inquire about triggers for additional reports by visiting the Permit Intake Center, 747 Market Street, or by calling 253-591-5030.

ASARCO Soil Sampling

Development proposals located in areas with a probability of high amounts of contamination from the ASARCO Plume may require soil testing.  The Department of Ecology (DOE) provides an online Facilities Atlas Map to help determine the level of contamination:

Cultural Resources Assessment

Proposals within a Shoreline District, within Puyallup Tribal Boundaries, or on a historically significant site require a Cultural Resources Report.  Depending on the scope and location of the project, an Unanticipated Discovery Plan by an approved Archaeologist may suffice.

Traffic Impact Analysis

Based upon the amount of traffic your proposal may generate, a traffic worksheet or a full Traffic Impact Analysis may be requested. A Traffic Engineer can be reached at 591-5500.

Critical Areas Report

Projects within wetlands, fish and wildlife habitat conservation areas, or associated buffers will require a critical areas report.  Projects within flood-sensitive areas may require elevation certificates, and areas with steep slopes (greater than 40% grade) often require submittal of a geotechnical report.

Applicable Regulations

Tacoma Municipal Code 13.12 – Environmental Code

Washington Administrative Code 197-11 SEPA Rules

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