Boeing Kent Space Center
20403 68th Ave S, Kent, WA 98032

Boeing Kent Space Development Center sporting the 12th Man flag.
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Last Updated November, 2018

Boeing is conducting a remedial investigation (RI) to determine the type, location and concentrations of contamination on this site.  We are overseeing Boeing’s work under a legal agreement (Agreed Order or Order). The investigation requires Boeing to sample soil, groundwater, and water and sediment in its stormwater management system. The findings of the investigation will be described in a remedial investigation report.

What's Next?

Boeing submitted a draft of the RI report to us in December 2017 and then additional information in 2018.  We reviewed that draft and decided that more information was still needed to understand where the different contaminants are found and their concentrations.  Now Boeing must submit a detailed plan about what sampling they are going to do get that information. After Boeing completes the sampling they will revise the RI Report for us to review. We will hold a public comment period for the final RI report in 2019.


Boeing has conducted research and development at this facility, mostly for the U.S. Department of Defense.  Since the 1960’s Boeing has also conducted operations related to aerospace related operations. These activities, include; electronic and electrical component manufacturing, metal milling, finishing and plating, photographic processing, and research and development in various laboratories. Chemicals used in those operations spilled and contaminated soil and groundwater.  In 2016 Ecology issued the Order that required Boeing to conduct the RI. We approved the RI work plan later that year.Boeing also previously stored hazardous waste at this site long term (under a federal Environmental Protection Agency Resource Conservation and Recovery Act, RCRA, interim status, 40 CFR Part 265.)  Now, Boeing can now only store hazardous waste for up to 90 days.

Remediated property ready for redevelopment.
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Contaminants have been detected in groundwater, soils, soil gas, stormwater, and/or sediments. They include:

• volatile organic compounds (VOCs) such as benzene and vinyl chloride
• petroleum hydrocarbons
• semi-volatile organic compounds ( “SVOCs”), including polycyclic aromatic hydrocarbons (or “PAHs”)
• PCBs 
• toxic metals

The levels of contamination found in many of the soil and groundwater sampling locations was relatively low and less than the levels that pose a risk to human health (referred to as risk-based screening levels) or the environment.  At some locations one or more contaminant concentrations were higher than the risk-based screening levels. They include samples from soil gas and stormwater system sediments. 

At this time, we do not believe that people are exposed to harmful levels of contamination because Boeing controls public access and most of the contamination is covered.  If we discover that people are coming in contact with harmful levels, we will direct Boeing to quickly take protective actions. We will know more about the concentrations and locations of the contaminants when the RI is completed.

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The purpose of the first step of the cleanup process, the RI, is to gather data. All parts of the process will be made available for public review and comment.

That data from the RI will be used to propose and evaluate cleanup alternatives (feasibility study or FS) and develop a cleanup action plan (CAP) if needed.

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You can see the sampling results in Boeing’s 2017 draft RI Report vol.1, 2017 draft RI Report vol. 2), RI Report Addendum, and RI Report Addendum 2   Below are the locations that were investigated.

• Former underground storage tanks (KS-2.5 and KS-26) in Building 18-43 (SWMU-88 and SWMU-89).
• Former underground storage tanks (KS-5 and KS-6), north side on Building 18-54 (AOC-1 and AOC-3).
• Former underground storage tank (KS-7), north side on Building 18-35 (AOC-2).
• Former milling machine area in Building 18-62.
• Former underground storage tank area adjacent to Building 18-67.
• Former underground storage tank location near Door W-3 west side of Building 18-42.
• Former leaking underground storage tank at Building 18-41.
• Stormwater management system (SWMU-86).


Map showing site location as King County, WA SITE INFORMATION


View Electronic Documents

Cleanup Site Details Report

Facility Site ID: # 2099

Cleanup Site ID: 12671

Kent, King County

Status: Awaiting Cleanup   Get definitions of Status terminology

Ed Jones
Site Manager
(425) 649-4449

Thea Levkovitz
Public Involvement Coordinator
(425) 649-7286

Document Repositories:

Northwest Regional Office
3190 160th Ave SE
Bellevue, 98008

King County Library - Kent Library
212 2nd AVE N
Kent, 98032