Facility Site ID: 56257757 Cleanup Site ID: 15113

  • Site Status

  • Awaiting Cleanup

Current Status

Aerial view of 601 Dexter cleanup site
Aerial view of 601 Dexter cleanup site

Last Updated:  September 2022

以下是有關清理工作的中文信息
Información en español abajo

Fact Sheets

English
有關清理工作的中文信息
En español


601 Dexter site moves towards interim action and remedial investigation

Ecology held a 30-day comment period (August 15 - September 13, 2022) on a legal agreement called an Agreed Order with ARE Seattle No. 32 LLC (ARE) for the 601 Dexter cleanup site (site). The Agreed Order names ARE as the Potentially Liable Person (PLP) and requires them to address contamination at the site.

Ecology has reviewed the one comment received and no changes were necessary in the documents, and they are being finalized now: 

  • Agreed Order:  legal document that requires the PLP to investigate environmental conditions, complete a Remedial Investigation (RI), Feasibility Study (FS), and a draft Cleanup Action Plan (dCAP) for the site. This Agreed Order also includes a description of interim cleanup work to be completed during the RI.
  • Public Participation Plan:  describes how Ecology will inform the community about site activities and ways to be involved in the cleanup process.
  • State Environmental Policy Act (SEPA) Checklist and Determination of Non-Significance (DNS):  evaluation and determination that the proposed cleanup at the site is not likely to cause harm.
En español
El department de Ecología está anunciando el periodo de comentario público relacionado a la limpieza ambiental del sitio 601 Dexter. Para obtener este documento, o más información sobre este sitio, en español favor de comunicarse con Tanner Bushnell al preguntas@ecy.wa.gov. 

中文
華盛頓州生態管理署邀請公眾對601 Dexter地產清理工作的清理行動 計劃草案動提供建意見。 欲了解更多信息, 或要求翻譯服務,請致 電林昊 (425) 457-3842,電子郵件 sunny.becker@ecy.wa.gov

Email List

Join our email list to receive updates about the South Lake Union cleanup sites, including 601 Dexter. You may also email the Public Involvement Coordinator (listed under Contacts) to be added to the list. Unsubscribe at any time.

Subscribe Here!

Why This Site Matters

601 Dexter cleanup site in Seattle's South Lake Union Neighborhood
601 Dexter cleanup site in Seattle's South Lake Union Neighborhood
The 601 Dexter site is part of the South Lake Union neighborhood, which is located next to downtown Seattle and bordered on the north by Lake Union.  This area has a long history of industrial and commercial activities which caused contamination of the soil and groundwater.  Currently, this area is undergoing extensive redevelopment as new buildings are constructed for commercial and residential use.   Ecology is working with property owners to clean up contamination present at this site and other nearby sites to reduce impacts to human health and the environment.




General Cleanup Process

Click image to enlarge
Click image to enlarge
The Model Toxics Control Act (MTCA) is Washington’s environmental cleanup law. It provides requirements for contaminated site cleanup and sets standards that protect human health and the environment. Ecology enacts the MTCA and oversees cleanups. The MTCA site cleanup process is completed in steps (see graphic below) over a variable timeline.

Estimate Site Timeline

  • August 15 - September 13, 2022: Ecology held a public comment period for Agreed Order, Public Participation Plan, and SEPA Determination.
  • Later 2022:   Ecology considered all comments received during this public comment period and is finalizing the documents. The PLPs will proceed with the RI, interim cleanup actions, FS, and CAP. 

Each of those steps will require a public comment period. The graphic above shows these different stages of cleanup. Sometimes multiple stages occur in one comment period. 

Public Participation

Current 601 Dexter cleanup site Public Participation Plan

This plan includes information for the public regarding opportunities to get involved in the Site cleanup process. The outreach activities and mechanisms presented reflect Ecology’s current plans for keeping the public informed and for receiving information and comments from the public. 

Site Information

Street view of 601 Dexter cleanup site
Street view of 601 Dexter cleanup site

Site background
The site is generally located at 601 Dexter Ave N in Seattle’s South Lake Union neighborhood. It includes one King County parcel that is approximately 0.54 acres (Property). Currently, there is a commercial building occupied by Copiers Northwest and a parking lot in the northeastern part of the Property. An alley right-of-way owned by the City of Seattle separates the Property from the adjacent property (615 Dexter Ave N). 

The building currently occupying the Property was constructed in 1919 with additional offices constructed in 1962. Former commercial tenants include Modern Automobile and Tractor School, Dexter Cabinet Works, and Colotyle Corporation, a manufacturer of a tile substitute.

Past uses of the site include a laundry and cleaning business during the 1930s and 1940s and a small fueling station during the 1940s and 1950s.

Site investigation and contamination
Investigations at the site show the following hazardous substances in the soil and groundwater: 

  • Soil: gasoline
  • Groundwater: gasoline 

These contaminants are present at levels that exceed allowable standards under the state’s cleanup law, the Model Toxics Control Act (MTCA), and must be addressed. 

Some of these hazardous substances were also found in the alley right-of-way north of the Property. 

Under certain conditions, contamination below ground can become hazardous in the air at a cleanup site. This is called vapor intrusion. Acrolein and Naphthalene were detected at concentrations greater than screening levels in soil vapor studies at the site.

Legal 3
Document Title Document Date Document Type
Agreed Order 601 Dexter Final 10/12/2022 Agreed Order
601 Dexter - Agreed Order Draft - July 2022 7/22/2022 Agreed Order
601 Dexter - Early Notice Letter 12/18/2019 Early Notice Letter
Public Information 4
Document Title Document Date Document Type
601 Dexter - Public Participation Plan - September 2022 9/16/2022 Public Participation Plan
601 Dexter - Fact Sheet - August 2022 CHINESE 8/8/2022 Fact Sheet\Public Notices
601 Dexter - Fact Sheet - August 2022 SPANISH 8/8/2022 Fact Sheet\Public Notices
601 Dexter - Fact Sheet - August 2022 8/8/2022 Fact Sheet\Public Notices
State Environmental Policy Act 1
Document Title Document Date Document Type
601 Dexter - SEPA Determination of Non-Significance and Checklist - July 2022 7/13/2022 SEPA Documents
Technical Reports 3
Document Title Document Date Document Type
601 Dexter - Initial Investigation Field Report 12/9/2019 Initial Investigation Report
601 Dexter - Phase II ESA 5/23/2019 Site Specific Technical Document - other
601 Dexter - Phase I ESA 5/23/2019 Site Specific Technical Document - other
There may be more documents related to this site. To obtain documents not available electronically, you will need to make a public records request.

Places to see print documents

  • Northwest Regional Office
    15700 Dayton Ave N
    Shoreline, 98133
    Please schedule an appointment to view print documents at this location.
  • Seattle Public Library - Central
    1000 Fourth Ave
    Seattle, 98104
    This location may only have print documents available during open comment periods.

Contaminants 14

Contaminant Type
Soil
Groundwater
Surface Water
Air
Sediment
Bedrock
Metals - Metals - Other B C
Halogenated Organics - Polychlorinated biPhenyls (PCB) B
Non-Halogenated Organics - Non-Halogenated Solvents B C
Non-Halogenated Organics - Polycyclic Aromatic Hydrocarbons B B
Halogenated Organics - Halogenated Solvents B B C
Metals - Arsenic B C
Non-Halogenated Organics - Methyl tertiary-butyl ether B B
Metals - Lead B C
Metals - Mercury B B
Non-Halogenated Organics - Benzene B B
Non-Halogenated Organics - Other Non-Halogenated Organics B B
Non-Halogenated Organics - Petroleum-Diesel B B
Non-Halogenated Organics - Petroleum-Gasoline C C
Non-Halogenated Organics - Petroleum-Other B B
S
Suspected
C
Confirmed Above Cleanup Levels
B
Below Cleanup Levels
RA
Remediated-Above
RB
Remediated-Below
R
Remediated
This contaminant list was based on our best information at the time it was entered. It may not reflect current conditions at the site.