Site Description
Terminal 30 (T-30) is a 33.9-acre property addressed at 1901 East Marginal Way South in Seattle, Washington. The Site is located on the shoreline of the East Waterway near the mouth of the Lower Duwamish Waterway (LDW). T-30 is bound by terminal property to the north, East Marginal Way South to the east, a vessel slip to the south, and by the East Waterway to the west. The cleanup Site is comprised of one large and one small area totaling approximately 11 acres located in the northern portion of the property. T-30 currently operates as a freight terminal and provides shipping container storage.
Site History
Prior to the channelization of the Duwamish River in the 1900s, the land occupied by present-day T-30, was part of the Elliot Bay tide flats. During channelization, the flats were filled with various materials including dredged soils. In 1905, the Standard Oil Company (now Chevron) occupied the northern portion of the Site and operated as a bulk fuel terminal. The southern portion of the terminal was used for a variety of industrial operations, including a lumber yard, a machine shop, and a shipyard. In 1950, Chevron expanded the fuel terminal to the southern portion of the Site. In 1985, the Port of Seattle purchased the Site from Chevron and redeveloped it as a cargo container terminal. From 2003-2008 the Site included a cruise ship terminal. T-30 is currently operating as a freight terminal and provides temporary cargo storage.
Contamination Issue
As 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. In the 1980s, Chevron discovered petroleum contamination in the soil and groundwater and initiated the cleanup work. In 1985, upon purchasing the property from Chevron, the Port inherited the property’s historical contamination and entered into an agreement with the Washington State Department of Ecology (Ecology) that established the cleanup criteria. Contaminants in the soil include Total Petroleum Hydrocarbons (TPH). Groundwater contaminants include TPH, including gasoline, diesel, and motor oil range hydrocarbons; Volatile Organic Compounds (VOCs) including benzene; and Polycyclic Aromatic Hydrocarbons (PAHs). An on-site stormwater management system treats stormwater runoff using oil and water separators and filters before discharging the water into the East Waterway. Contaminated groundwater does not enter the on-site stormwater system.
Why is the Port Doing this Cleanup?
The Site’s operational history as a fuel terminal led to contamination of soil and groundwater. The Port continues cleanup efforts at T-30 to ensure the protection of human health and prevent contamination discharging into the East Waterway, which is an active Superfund Site.
The cleanup is being conducted under an Agreed Order (AO) between Ecology and the Port. The AO requires the Port implement the remedial actions in the Cleanup Action Plan (CAP), including confirmation, performance, and compliance monitoring. The Port currently performs quarterly air sparging and soil vapor extraction treatment and light non-aqueous phase liquid (LNAPL) recovery.
Status
The Site is currently in the long-term operation and maintenance (O&M) phase of the cleanup. The Port operates the onsite air sparge/soil vapor extraction (AS/SVE) system and performs vapor monitoring twice per month, as well as monthly LNAPL gauging as described in the Compliance Monitoring Plan (CMP) and quarterly LNAPL recovery. Groundwater monitoring is performed on a semiannual basis, where sampling is conducted at performance, interior, and conditional point of compliance (CPOC) monitoring wells.
Contact Information
Jalyn Buckley | Environmental Management Specialist | [email protected]
Additional Resources
Visit Ecology’s Terminal 30 Cleanup Site page for more information.
