Facility Site ID: 70525886 Cleanup Site ID: 16913

Public Comment Period April 01, 2024-April 15, 2024

Draft State Environmental Policy Act (SEPA) documents

*Información en Español*

You are invited to comment on the draft SEPA documents for replacing the underground storage tank (UST) system at Stillwater Holdings Chevron. We have reviewed the SEPA checklist about the project, and decided it won’t negatively affect people or the environment.

This work will include:

  • Excavating the existing UST system 
  • Removing and disposing of the existing UST system
  • Installing a new UST system
  • Backfilling the excavated area with clean, imported soil
Review the draft documents
Submit comments to Beth Kercher by 4/15

Email: beth.kercher@ecy.wa.gov
Mail: 4601 N. Monroe St., Spokane, WA 99205
Online: Comment form

Ley de la Política Ambiental Estatal (SEPA)

Ecología ha revisado la información acerca del reemplazo del tanque almacenaje subterráneo para determinar si tendrá impactos negativos a las personas o el medio ambiente. Documentos de la Ley de la Política Ambiental Estatal (SEPA por sus siglas en inglés) explican esta evaluación y están disponibles para comentario público.

Cleanup Planning Underway

Testing the lines and tanks at the Stillwater Holdings Chevron.
Testing the lines and tanks at the Stillwater Holdings Chevron.

The Stillwater Holdings Chevron owner hired an environmental consultant and underground storage tank (UST) contractor to complete an investigation and develop a plan for cleanup, which Ecology will review and provide input on.

Two tank systems operating until all three are decommissioned

Ecology worked with the owner and their UST contractor to safely put the tanks identified as not leaking temporarily back into use in December 2023.

Based on several tests, the diesel and premium gasoline UST systems meet Washington’s regulations and can store and dispense fuel. The owner worked with Ecology’s UST Program to accept regular gasoline in the premium gasoline UST (download red-tag removal letter). The regular gasoline UST was the source of the release. 

Stillwater Holdings Chevron’s consultants are working with the City of Walla Walla to decommission all three UST systems and replace them with new ones. During decommissioning, contaminated soil will also be removed. Tank removal planning will occur January through March 2024, and the work is scheduled to begin in April.

Area Safe & Monitored

Local, state and federal agencies along with third-party contractors have deemed the area safe for residents and visitors. Monitoring and testing of Walla Walla's municipal water and wastewater systems, and Mill Creek, show no evidence of contamination. Engineering controls have been put in place to ensure the air, water, and soil in the area are continually monitored and pose no risk of future contamination.

Site History

On September 14, 2023, the Marcus Whitman Hotel was evacuated due to volatile organic vapors entering the building, also known as vapor intrusion. The Walla Walla Fire Department called in Ecology’s Spill Response Team to help assess the situation and identify the source. The hotel and other impacted buildings were ventilated to eliminate the risk of an explosion.

Gasoline was collecting in adjacent building sumps, which were pumped to help reduce vapor concentrations. The nearby Circle K and Stillwater Holdings Chevron gas stations performed tank and line tests of their UST systems, and issues were found on the regular unleaded gasoline UST system at the Stillwater Holdings Chevron, also known as the Wine Country Store. Analysis of the gas collected from the building sumps showed it matched the regular gasoline at Stillwater Holdings Chevron.

Site use restrictions called institutional controls are in effect

Institutional controls can be fences, signs, or restrictions on how the property is used. For instance, an institutional control may prohibit installing drinking water wells or disturbing a protective cap that isolates contamination. These restrictions keep the contamination contained and keep people from being exposed to the contamination. The controls are usually listed in environmental covenants recorded with the county.

Periodic reviews are required when institutional controls are required at a site. Ecology conducts reviews to make sure the controls remain effective and the cleanup still protects human health and the environment. We conduct periodic reviews about every five years.

Environmental Covenant

County Recording #: 2013-04956
County Recording Date: 5/17/2013

Restrictions/Requirements

  • Prevent the Reuse or Relocation of Site Soil
  • Prohibit Soil Disturbance
  • Restrict Land Use

Restricted Media

  • Soil
Legal 1
Document Title Document Date Document Type
Bill Singers Chevron - Environmental Covenant 5/20/2013 Environmental Covenant; Alternative Mechanism
Map 1
Document Title Document Date Document Type
DRAFT Proposed Test Pit Investigation Locations 12.2023: Stillwater Holdings Chevron 12/28/2023 Map
State Environmental Policy Act 1
Document Title Document Date Document Type
SEPA Checklist & Determination of Non-significance: Stillwater Holdings Chevron UST replacement 4/1/2024 SEPA Documents
Technical Reports 19
Document Title Document Date Document Type
Vapor Intrusion Evaluation Workplan: Marcus Whitman Hotel 3/27/2024 Site Specific Technical Document - other
Notification of Ecology’s Invitation to begin new Agreed Order negotiations: Stillwater Holdings Chevron 2/27/2024 Site Specific Administrative Document - other (Administrative correspondence)
Industrial Pretreatment Program – Application for Wastewater Discharge Permit: Stillwater Holdings Chevron 2/26/2024 Site Specific Technical Document - other
Geotechnical Engineering Study and Temporary Shoring Design: Stillwater Holdings Chevron 2/22/2024 Site Specific Technical Document - other
Comments on Marcus Whitman Hotel Vapor Intrusion Evaluation Workplan for Stillwater Holding Chevron, Walla Walla, Washington 2/21/2024 Site Specific Administrative Document - other (Administrative correspondence)
Ecology Letter to Stillwater Holdings re: Reconciliation Records: Stillwater Holdings Chevron 2/12/2024 Site Specific Administrative Document - other (Administrative correspondence)
Marcus Whitman Hotel Vapor Intrusion Evaluation Workplan DRAFT: Stillwater Holdings Chevron 2/7/2024 Site Specific Technical Document - other
Ecology Letter Response to City of Walla Walla: Stillwater Holdings Chevron 1/29/2024 Site Specific Technical Document - other
Ecology Preliminary Determination of Liability: Stillwater Holdings Chevron 1/18/2024 Site Specific Technical Document - other
City of Walla Walla Letter to Ecology: Stillwater Holdings Chevron 1/12/2024 Site Specific Technical Document - other
Ecology Comments on Comments on VI Mitigation and Conceptual VI Assessment: Stillwater Holdings Chevron 12/6/2023 Site Specific Technical Document - other
Authorized Removal of Red Tag on UST Tank (PREM): Stillwater Holdings Chevron 11/21/2023 Site Specific Administrative Document - other (Administrative correspondence)
Ecology Comments on Proposed Cleanup: Stillwater Holdings Chevron 11/21/2023 Site Specific Administrative Document - other (Administrative correspondence)
Draft Conceptual VI Mitigation Plan: Stillwater Holdings Chevron 11/17/2023 Site Specific Technical Document - other
Work Plan for Additional Subject Property Investigation - DRAFT: Stillwater Holdings Chevron 11/10/2023 Site Specific Technical Document - other
Draft Vapor Mitigation Plan: Marcus Whitman Hotel 10/26/2023 Site Specific Technical Document - other
Work Plan for Initial Subject Property Investigation: Stillwater Holdings Chevron 10/11/2023 Site Specific Technical Document - other
Amended Notice Report and Order of Unsafe Structure: Stillwater Holdings Chevron 10/6/2023 Site Specific Administrative Document - other (Administrative correspondence)
Ecology Spills Technical Assistance Regarding Gasoline Release: Stillwater Holdings Chevron 10/3/2023 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

  • Eastern Regional Office
    N 4601 Monroe St
    Spokane, 99205-1265
    Please schedule an appointment to view print documents at this location.

Contaminants 3

Contaminant Type
Soil
Groundwater
Surface Water
Air
Sediment
Bedrock
Non-Halogenated Organics - Benzene C
Non-Halogenated Organics - Other Non-Halogenated Organics C
Non-Halogenated Organics - Petroleum-Gasoline C C C
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.