Boeing Kent Space Center
Facility Site ID:
2099
Cleanup Site ID:
12671
Current Status
Last updated March, 2026
The feasibility study on this site went out for public comment from August 25 - September 26, 2025. No comments were received, and the feasibility study is now final. We modified the agreed order to require Boeing to prepare a draft cleanup action plan. The draft cleanup action plan will be out for public comment period from March 23 - April 24, 2026.
What's Next?
The cleanup action plan will document how to fix the arsenic contamination in groundwater at the site. After public comment on the draft cleanup action plan is received, we will consider all comments and may change the plan based on feedback.
The feasibility study on this site went out for public comment from August 25 - September 26, 2025. No comments were received, and the feasibility study is now final. We modified the agreed order to require Boeing to prepare a draft cleanup action plan. The draft cleanup action plan will be out for public comment period from March 23 - April 24, 2026.
What's Next?
The cleanup action plan will document how to fix the arsenic contamination in groundwater at the site. After public comment on the draft cleanup action plan is received, we will consider all comments and may change the plan based on feedback.
Site Background
Boeing has operated here since the 1960s, conducting research and development (primarily for the Department of Defense). They also manufacture electrical components and perform metal milling, finishing and plating, and photographic processing here. These activities led to contaminated soil and groundwater.
Boeing used to store hazardous waste longer than 90 days at this site under a Resource Conservation and Recovery Act (RCRA) interim status permit. Boeing decided not to get a final permit. As a result, they can only store hazardous waste for up to 90 days. Even though they did not get a final permit, Boeing must keep their permit active until they clean up the site.
In 2016, an Agreed Order (AO) was signed that required Boeing to conduct a remedial investigation (RI). Boeing conducted an RI to determine the type, location and concentrations of contamination on this site. We oversee Boeing’s work under a legal agreement (Agreed Order or Order). Boeing sampled soil, groundwater, indoor air and water and sediment in its stormwater management system.
Boeing submitted draft RI reports in 2017, 2018, 2019 and 2020. We required revisions of these drafts. The final 2022 RI report can be found in the "documents" section below.
In 2023, an AO Modification required Boeing to do a focused feasibility study. That feasibility study went out for public comment August 25 - September 26, 2025. No comments were received and the documents are now final. A cleanup action plan based on the feasibility study is out for public comment March 23 - April 24, 2026.
Boeing used to store hazardous waste longer than 90 days at this site under a Resource Conservation and Recovery Act (RCRA) interim status permit. Boeing decided not to get a final permit. As a result, they can only store hazardous waste for up to 90 days. Even though they did not get a final permit, Boeing must keep their permit active until they clean up the site.
In 2016, an Agreed Order (AO) was signed that required Boeing to conduct a remedial investigation (RI). Boeing conducted an RI to determine the type, location and concentrations of contamination on this site. We oversee Boeing’s work under a legal agreement (Agreed Order or Order). Boeing sampled soil, groundwater, indoor air and water and sediment in its stormwater management system.
Boeing submitted draft RI reports in 2017, 2018, 2019 and 2020. We required revisions of these drafts. The final 2022 RI report can be found in the "documents" section below.
In 2023, an AO Modification required Boeing to do a focused feasibility study. That feasibility study went out for public comment August 25 - September 26, 2025. No comments were received and the documents are now final. A cleanup action plan based on the feasibility study is out for public comment March 23 - April 24, 2026.
Contamination
Contaminants found in groundwater and soil at Boeing Kent Space Center include:
• Volatile organic compounds (VOCs), such as benzene and vinyl chloride. These chemicals cause cancer.
• Petroleum hydrocarbons (the main parts of gasoline and oil).
• Semi-volatile organic compounds (SVOCs), including polycyclic aromatic hydrocarbons (PAHs). These chemicals are formed when gasoline or trash are burned. PAHs are suspected to cause cancer.
• Polychlorinated biphenyls (PCBs), long-lasting chemicals formerly used in industry. Health effects of PCBs can include cancer and immune system damage. Read more about PCBs at https://www.epa.gov/pcbs.
• Toxic metals, such as arsenic. Arsenic is naturally occurring and is mobilized by some forms of contamination. Arsenic is poisonous and regulated in public drinking water.
Contamination at this site is relatively low, and people are not being exposed. This is because groundwater at the site is not used for drinking water, and Boeing controls access to their property. If contamination threatening human health or the environment is found, we will have Boeing take protective action.
• Volatile organic compounds (VOCs), such as benzene and vinyl chloride. These chemicals cause cancer.
• Petroleum hydrocarbons (the main parts of gasoline and oil).
• Semi-volatile organic compounds (SVOCs), including polycyclic aromatic hydrocarbons (PAHs). These chemicals are formed when gasoline or trash are burned. PAHs are suspected to cause cancer.
• Polychlorinated biphenyls (PCBs), long-lasting chemicals formerly used in industry. Health effects of PCBs can include cancer and immune system damage. Read more about PCBs at https://www.epa.gov/pcbs.
• Toxic metals, such as arsenic. Arsenic is naturally occurring and is mobilized by some forms of contamination. Arsenic is poisonous and regulated in public drinking water.
Contamination at this site is relatively low, and people are not being exposed. This is because groundwater at the site is not used for drinking water, and Boeing controls access to their property. If contamination threatening human health or the environment is found, we will have Boeing take protective action.
Cleanup
This site is in the Cleanup Action Plan phase of Washington's cleanup process.
Boeing must clean up the contamination to protect human health and the environment from dangerous wastes and chemicals.The Feasibility Study found the most permanent and practical cleanup remedy. This remedy is the subject of the draft Cleanup Action Plan. The remedy uses monitored natural attenuation (MNA). With MNA, we let natural processes reduce contamination under close monitoring. We check the progress of the cleanup by taking regular groundwater samples and testing them for contamination. This remedy protects people and animals by reducing arsenic in groundwater over time. The remedy will permanently meet cleanup goals and prevent activities that might interfere with the cleanup.
Documents 38
Legal 4
| Document Title | Document Date | Document Type |
| 2ndAmend_AO_BoeingKent_1-2-2026 | 1/2/2026 | Agreed Order |
| Boeing Kent Final Agreed Order Amendment | 2/1/2023 | Agreed Order |
| Boeing Kent Space Center Agreed Order # 12820 | 1/19/2016 | Agreed Order |
| Boeing Kent Space Center - Determination of Potentially Liable Person Status Letter | 10/8/2014 | Final Potentially Liable Person Status Letter |
Map 1
| Document Title | Document Date | Document Type |
| Boeing Kent Site Diagram | 1/25/2023 | Map |
Outreach Information 8
| Document Title | Document Date | Document Type |
| Boeing Kent Public Notice Mailer 2026_Spanish_ADA | 3/16/2026 | Fact Sheet\Public Notices |
| Boeing Kent Space Center 2026 Public Notice Mailer_ADA | 3/5/2026 | Fact Sheet\Public Notices |
| Boeing Kent Space Center Public Notice 2025 | 8/18/2025 | Fact Sheet\Public Notices |
| Boeing Kent Space Center Public Participation Plan 2025 | 8/18/2025 | Public Participation Plan |
| Boeing Kent Space Center Public Notice SPANISH 2025 | 8/18/2025 | Fact Sheet\Public Notices |
| Boeing Kent Space Center Public Participation Plan FINAL 2023 | 2/28/2023 | Public Participation Plan |
| Boeing Kent Space Center Public Comment Period Radio Ad 2023 | 2/27/2023 | Multimedia |
| Boeing Kent Space Center Public Notice 2022 | 11/21/2022 | Fact Sheet\Public Notices |
State Environmental Policy Act 2
| Document Title | Document Date | Document Type |
| SEPA DNS for Boeing Kent Space Center | 1/22/2026 | SEPA Documents |
| BoeingKent_SEPA_Checklist_20260113 | 1/13/2025 | SEPA Documents |
Technical Reports 22
Tribal Engagement 1
| Document Title | Document Date | Document Type |
| Tribal Engagement Plan Boeing Kent Space Center March 2026 FINAL | 3/19/2026 | Tribal Engagement Plan |
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 Office15700 Dayton Ave NShoreline, 98133This location may only have print documents available during open comment periods.
-
Kent Public Library212 2nd Ave NKent, 98032This location may only have print documents available during open comment periods.
Contaminants 9
| Contaminant Type | Soil |
Groundwater |
Surface Water |
Air |
Sediment |
Bedrock |
|---|---|---|---|---|---|---|
| Metals - Metals - Other | S | S | S | |||
| Halogenated Organics - Polychlorinated biPhenyls (PCB) | S | |||||
| Non-Halogenated Organics - Non-Halogenated Solvents | S | S | S | |||
| Halogenated Organics - Halogenated Solvents | S | S | S | |||
| Metals - Arsenic | S | S | S | |||
| Non-Halogenated Organics - Benzene | S | S | S | |||
| Non-Halogenated Organics - Petroleum-Diesel | S | S | S | |||
| Non-Halogenated Organics - Petroleum-Gasoline | S | S | S | |||
| Non-Halogenated Organics - Petroleum-Other | S | S | S |
- 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.
Cleanup Documents Available For Review And Comment
· Draft Cleanup Action Plan (dCAP): This plan describes the cleanup and sets the standards that the cleanup must meet.
· Draft Agreed Order (AO): This legal agreement ensures that the cleanup follows state law.
· Draft State Environmental Policy Act/Determination of Non-Significance (SEPA/DNS): We use SEPA during site cleanups to find and evaluate negative environmental impacts that could result from a proposed action. The draft SEPA resulted in a determination of non-significance, meaning that this work will not have large negative environmental impacts.
Submit comments online: ecology.wa.gov/BoeingKentComment
By mail: Li Ma, Site Manager, Department of Ecology, Northwest Region Office, P.O. Box 330316, Shoreline, WA 98133
Public meeting: At this time, there are no public meetings scheduled for this comment period. To request a public meeting, please call 425-301-6454 or email janelle.anderson@ecy.wa.gov.
What happens next?
The public comment period is open from March 23 to April 24, 2026. After the comment period ends, we will review and consider all comments we receive. The documents may change based on your comments. After we consider all the comments, the documents will become final. When there are new documents about the site, we’ll notify you about additional public comment periods.
Language Services: We offer translation and interpretation services at no cost. To request them, email janelle.anderson@ecy.wa.gov or call 425-301-6454. If you call, please ask for an interpreter.
Español (Spanish): El Departamento de Ecología está anunciando el período de comentarios públicos relacionado a la limpieza ambiental del sitio Boeing Space Center en Kent. Lea el documento en español. Si tiene alguna pregunta sobre la limpieza o sobre cómo hacer comentarios, contacte a Janelle Anderson llamando al 425-301-6454 o escribiendo a janelle.anderson@ecy.wa.gov. Por favor solicite un intérprete al hacer su llamada y espere a que le conecten con uno. El Departamento de Ecología ofrece servicios de traducción e interpretación libre de costo.