Facility Site ID: 53578168 Cleanup Site ID: 6240

Site Status - July 2021

Bothell Riverside Sites & Vicinity
Bothell Riverside Sites & Vicinity

Ecology has negotiated two new legal agreements called Agreed Orders with the City of Bothell (City), the Potentially Liable Person (PLP) for the Bothell Riverside TPH and Bothell Riverside HVOC Sites. These orders will replace an existing 2009 Agreed Order for the original Bothell Riverside Site.

In November 2019, Ecology hosted a public comment period for these orders, a SEPA Determination, and a Public Participation Plan:


• Agreed Order – Riverside TPH Site: states that contamination was removed through interim cleanup actions in 2010 and 2017, and is in compliance with safe cleanup levels required under Washington’s cleanup law, the Model Toxic Control Act (MTCA). Ecology will remove this Site from its Hazardous Sites List (HSL).
• SEPA (State Environmental Policy Act) Checklist & DNS (Determination of Non-Significance): states that the Cleanup Action Plan for the Riverside TPH Site will not cause environmental damage.
• Agreed Order – Riverside HVOC Site: requires the City to complete a Supplemental Remedial Investigation, Feasibility Study, Interim Action, and draft Cleanup Action Plan for the Site.
• Public Participation Plan: updates a 2017 Plan that describes how Ecology will inform the community about Site activities and opportunities to be involved in the cleanup process.

Ecology received no comments that warranted changes to these documents, and therefore finalized them.  Ecology has also issued a letter of Satisfaction of Order and No Further Action to the City of Bothell for the Bothell Riverside Site.

Site Background

Bothell Riverside TPH & HVOC Sites
Bothell Riverside TPH & HVOC Sites
The Bothell Riverside TPH (Total Petroleum Hydrocarbons) and HVOC (Halogenated Volatile Organic Compounds) Sites are generally located at NE 180th Street & Woodinville Drive (SR 522) in Bothell. Originally, these were considered “areas” within the overall Riverside Site. In 2009, Ecology and the City entered into an Agreed Order to conduct investigations, develop cleanup alternatives, and perform interim cleanup actions in both areas.A former gasoline service station once operated at the Riverside Site. Investigations found petroleum contaminants in soil in the TPH area and chlorinated solvents in groundwater in the HVOC area.


Riverside TPH Site
Operations at the former gasoline service station caused petroleum contamination to get into the soil in the TPH area at cleanup levels higher than allowed under the Model Toxics Control Act (MTCA). In 2010, and again in 2017, the City conducted interim cleanup actions to partially address the contamination. The City excavated the petroleum-contaminated soil and disposed of it at a licensed off-site facility. These actions were successful in removing all contamination from the TPH area. No additional cleanup work is required there.

The new TPH Agreed Order now designates this former area as the Riverside TPH Site. It can now be removed from the Hazardous Sites List while separate work continues in the Riverside HVOC Site, which Ecology will do following public comment.

Riverside HVOC Site
Operations at the former gasoline service station are believed to have caused HVOC (chlorinated solvents, essentially from dry cleaning fluids and its breakdown products) to enter groundwater in the HVOC area at cleanup levels higher than allowed under MTCA.

In 2013, Ecology and the City agreed to amend the 2009 Agreed Order so that the City could conduct an interim cleanup action to prevent the chlorinated solvents from discharging into the Sammamish River. The City installed six extraction wells to collect solvent-contaminated groundwater and treat and discharge it into the sanitary sewer.

The new HVOC Agreed Order now designates this former area as the Riverside HVOC Site, allowing cleanup work to continue while the TPH Site is removed from the Hazardous Sites List. Under this order the City will complete a Supplemental Remedial Investigation, Feasibility Study, Interim Action, and preliminary draft Cleanup Action Plan for the Site. The City will also continue to implement the 2013 Interim Action.
Legal 9
Public Information 11
State Environmental Policy Act 5
Technical Reports 23
Document Title Document Date Document Type
Riverside Memo Additional soil and groundwater Sampling 11/9/2018 Remedial Investigation / Feasibility Study
Riverside HVOC area FS 2 7 18 2/7/2018 Remedial Investigation / Feasibility Study
Bothell Riverside TPH Final FS Report 12/18/2017 Feasibility Study
Bothell Riverside TPH Final CAP 12/18/2017 Cleanup Action Plan
Bothell Riverside - Final RI Report 12/18/2017 Remedial Investigation Report
Riverside HVOC GW Rpt Year 4, Quater 3 12/2/2017 Groundwater Monitoring Report
Riverside Soil Excavation Rpt 5 5 17 NO APP B_C 5/5/2017 Remedial Action Report
Riverside GW mon YR3-QTR4 (IA#2) 4/13/2017 Groundwater Monitoring Report
Riverside GW mon YR3-QTR4 (IA#2) 1/26/2017 Groundwater Monitoring Report
Riverside GW mon YR3-QTR3 (IA#2) 11/10/2016 Groundwater Monitoring Report
Riverside IAWP (second excavation in the TPH area) 10/12/2016 Remedial Investigation Work Plan
RiversideHVOC GW mon YR3-QTR2 (IA#2) 9/2/2016 Groundwater Monitoring Report
SOIL GAS SURVEY/ SOURCE INVESTIGATION 2/26/2016 Remedial Investigation / Feasibility Study
GROUND WATER MONITORING RESULTS YEAR 2, QUARTER 4 - DECEMBER 2015 1/25/2016 Groundwater Monitoring Report
Bothell Riverside - Interim Action Work Plan HVOC 2013 1/7/2013 Site Specific Technical Document - other
Interim Action Work Plan - Bothell Riverside 4/30/2010 Interim Action Documents
Safety and Health Plan - Bothell Riverside 2/28/2010 Health and Safety Plan
City of Bothell Response to Ecology's Opinion Review Letter dated 1/12/10 1/29/2010 Site Specific Administrative Document - other (Administrative correspondence)
Bothell Riverside Ecology's Opinion Review Letter on RI/FS Report and DCAP 1/1/2010 Site Specific Administrative Document - other (Administrative correspondence)
Bothell Riverside RI/FS Work Plan Amendment and Approval 8/18/2009 Engineering Design Report
Bothell Riverside RI/FS Work Plan 7/8/2009 Remedial Investigation Work Plan
Bothell Riverside - Site Hazard Assessment 6/22/2009 Site Hazard Assessment Report
City of Bothell Multi Site Health and Safety Plan 2/25/2009 Human Health and/or Eco Risk Assessment
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.
  • King County Bothell Regional Library
    18215 98th Ave NE
    Bothell, 98011
    This location may only have print documents available during open comment periods.
  • Bothell City Hall
    18415 101st Ave NE
    Bothell, 98011
    This location may only have print documents available during open comment periods.

Contaminants 4

Contaminant Type
Soil
Groundwater
Surface Water
Air
Sediment
Bedrock
Halogenated Organics - Halogenated Organics B RB
Metals - Metals Priority Pollutants B
Non-Halogenated Organics - Polycyclic Aromatic Hydrocarbons RB
Non-Halogenated Organics - Petroleum-Other RB RB
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.