Navigate Up
Sign In Section Home Port Home Contact Us

​Terminal 30 Remediation

Current operations at Terminal 30

T-30 aerialTerminal 30 (T-30) is a 31-acre container terminal located at 2431 E.
Marginal Way that provides a Seattle base for a major shipping line. Containerized freight is transferred between ships, trucks, and temporary terminal storage using cranes and forklifts.
The Port of Seattle acquired the property from Chevron in 1985 and developed it as a container terminal. From 2004-2008 the terminal was used as a cruise ship facility.
What's happening

The Port and the Washington State Department of Ecology
signed a Consent Decree (CD), agreeing on the remedy for Terminal 30.

The Cleanup Action Plan describes the cleanup, which will be designed in an Engineering Design Report and then installed upon Ecology’s approval. Monitoring will occur throughout construction and during operation of the cleanup.

Select this link to view the Consent Decree.

Cleanup Schedule

Click image to enlarge.

How was Terminal 30 contaminated?

T-30 historic dataAs early as 1905, the Standard Oil Company (now Chevron) operated a bulk petroleum handling and storage terminal on portions of T-30 where fuels including gasoline, diesel, and heating oil were stored in numerous above-ground tanks.

The operations released petroleum-related compounds that resulted in the accumulation of free-phase petroleum in the subsurface and contamination of soil and groundwater.


Additional FAQs about the project

What cleanup efforts happened in the past?
Environmental investigations and remediation at T-30 began in the early 1980s with Chevron’s discovery of petroleum contamination in soil and groundwater.

Nearly three decades of work by Chevron and the Port have included considerable study and interim actions:
  • Port and Ecology enter into Agreed Order (AO) for RI/FS in 1991
  • Installation of a product recovery system that removed more than 171,000 gallons of product by the early 1990s
  • Excavation and offsite disposal of more than 24,000 cubic yards of petroleum-impacted soil
  • Construction of site-wide 12 to 16-inch thick asphalt
  • Oxygen Release Compound injection in MW-42 area ccOxygen Release Compound injection in MW-42 area
  • Installation of more than 100 monitoring and recovery wells
  • Numerous technical studies and reports
  • Completion of the initial RI/FS in 1998
  • Installation of sheetpile wall and stormwater system in 2008-2009
  • Continuation of monitoring and product recovery during the 2000s
  • Additional Data Report, Disproportionate Cost Analysis, and proposed remedy in 2008
  • These cleanup actions were performed with Ecology oversight under a 1991 AO resulting in significant reductions in contaminant mass and risk.
  • Concurrently, the site was redeveloped from a bulk fuel facility into a busy shipping terminal that is an integral part of the Seattle shipping industry.
What are the chemicals of concern at T-30?
The chemicals of concern include gasoline, diesel, and heavy oil range petroleum hydrocarbons; benzene, toluene, ethylbenzene, and xylene compounds (BTEX), and polyaromatic hydrocarbons (PAHs).
What is the Selected Cleanup Remedy?
The remedy has three elements:
  1. air sparging and vapor extraction (AS/VE) to reduce contaminant mass in the western portion of the 3.2 acre sheen area;
  2. petroleum product removal by vacuum truck in one, small area where floating product can still be found on the groundwater; and
  3. long term groundwater monitoring to demonstrate that the cleanup system is operating as designed and no contamination is reaching the East Waterway.
What is Air Sparging and Vapor Extraction?
AS/VE involves bubbling air into the ground via a series of shallow wells to assist the bioremediation of petroleum that is already occurring naturally.

The AS/VE system will also extract petroleum vapors from the soil and groundwater sheen area and treat the extracted vapors so that they are not released to the air.
How will the collected vapors be treated so that they are not released to the air?
The soil vapor will be treated by oxidation with either a catalytic oxidizer or propane flame to combust 99% of vapors.

Later in the cleanup when vapor concentrations are low, the treated air will pass through carbon filters to remove any remaining, low levels of petroleum vapors.
Will there be air emissions caused by the cleanup? Are there health risks from the treated air emissions?
The soil vapor treatment will be designed to remove 99% of the petroleum vapors.
Final air emission levels are expected to be below normal ambient levels at the site.

Health risks are not expected from the treated air emissions and air monitoring will be performed to confirm. 
How will air monitoring be performed during the cleanup?
Air monitoring will be performed using a field tool called a Photoionization Detector (PID) to optimize the cleanup system and ensure terminal workers are safe in accordance with the project’s Health and Safety Plan.
What happens to the contaminated groundwater and free product that is removed during cleanup?
Contaminated groundwater and free product removed during cleanup will be properly transported and disposed of offsite at a facility permitted to receive and treat it.
What types of permits will the project get?
  • The permits required for this project are City of Seattle electrical permits or permits for the installation of remediation equipment.
  • Air permits will be obtained, if required by Washington Department of Ecology or the Puget Sound Clean Air Agency.
Why is the site required to be cleaned up?
  • The final assessment report (2015 RI/FS) concludes that the site is currently protective of human health and the environment.
  • The goals of this cleanup are to speed up the removal of subsurface petroleum at the site and continue to protect surface water in East Waterway.
Who is conducting the cleanup?
  • The Port of Seattle owns the property and is responsible for cleaning up the terminal.
  • The Washington Department of Ecology is the lead environmental regulatory agency and is responsible for the oversight of the project.
Is the Public allowed to enter the site during cleanup construction or operation of the system?
The site is an active shipping terminal. Access is restricted to Transportation Worker Identification Credential (TWIC)-certified personnel by appointment. The Public is not permitted to enter any active terminal property under the Marine Transportation Security Act.
What is the schedule for cleanup?
  • May 2016 – Consent Decree will be signed by the Port and the Washington Department of Ecology.
  • 2016-2017 – the Port will submit an Engineering Design Report for the remedy to the Washington Department of Ecology.
  • 2017-2018 – the Port will build the remedy.
  • 2016-2017 – the Port will monitor groundwater during this time period.
  • 2018-2027 – the Port will operate the AS/VE system and monitor groundwater and air quality as required by the Washington Department of Ecology and the Puget Sound Clean Air Authority.
  • 2018-2027 – the Port will perform groundwater monitoring to confirm that residual contamination at Terminal 30 continues to be protective of human health and the environment.
  • 2027-2047 – the Port will perform post-cleanup groundwater monitoring.
How can I contact someone or stay informed?














Consent Degree between Washington State Dept. of Ecology and the Port of Seattle


Washington State Ecology site page

Port of Seattle
Roy Kuroiwa
(206) 787-3814

Washington Department of Ecology Site Manager
Sunny Becker
(425) 649-7187

Washington Department of Ecology Public Involvement Coordinator
Nancy Lui
(425) 649-7117

Gound water well monitoring at Terminal 30.