Facility Site ID: 4446540 Cleanup Site ID: 2485

Cleanup Overview

The Sudbury Road Landfill is about 4 miles west of the City of Walla Walla and ½ mile north of Highway 12. The landfill sits on 125 acres in a mainly rural area. The City of Walla Walla owns and operates the landfill, which is used for disposal of the area's municipal solid waste (MSW). It disposed MSW in unlined areas from 1978 to 2006. It continues to dispose of MSW today, though in an area of the landfill that is lined.
 
Since 1977, the City has tested groundwater from wells around the landfill. In 2001, the City installed a new well. Tests on water from this new well show the groundwater contains chemicals, including volatile organic compounds, at levels that may be harmful to human health and the environment. Follow-up tests show the landfill is at least in part contributing to these impacts to groundwater.
 
In January 2011, the City did some work at the site to prevent groundwater impacts from becoming worse. The City placed a cover and installed gas and stormwater control systems over one unlined landfill cell, and diverted stormwater run-on away from another unlined landfill cell.

In May 2011, the Washington Department of Ecology and the City of Walla Walla worked through an Agreed Order requiring further investigation of contaminants from the site. The Agreed Order required the City of Walla Walla to conduct a Remedial Investigation and Feasibility Study, which it completed in 2012-2014. The City found chemicals (tetrachloroethylene and vinyl chloride) within the site at levels that need cleanup. It did not find these chemicals off-site at levels that need cleanup. In the study, preferred cleanup actions include improvements to landfill cover and stormwater controls, installation of gas control system, long-term groundwater and gas monitoring, and restrictions on property use. 

Through a May 2015 Consent Decree, the City began remedy construction as directed by a Cleanup Action Plan (CAP). The CAP included installation of landfill gas controls in three distinct areas, improved cover over two areas, improved grading to shed stormwater in one area, installation of stormwater controls at the northern edge of the landfill, ongoing groundwater monitoring, and property use restrictions through an Environmental Covenant. The City completed all construction in 2017, filed the Environmental Covenant in 2019, and monitors groundwater quarterly.

Periodic review

Ecology completed its first Periodic (5-Year) Review of cleanup effectiveness in 2022. Both contaminants of concern in groundwater (tetrachloroethylene and vinyl chloride) have decreased and have been at or below cleanup levels since March 2019 and December 2019, respectively.

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 #: 2019-08284
County Recording Date: 10/16/2019

Restrictions/Requirements

  • Restrict Land Use

Restricted Media

  • Soil
Legal 11
Document Title Document Date Document Type
Environmental Covenant 10/16/2019 Environmental Covenant; Alternative Mechanism
Consent Decree Exhibit C - Scope of Work and Schedule 8/19/2015 Consent Decree
Consent Decree Exhibit B - Cleanup Action Plan 8/19/2015 Consent Decree
Consent Decree Exhibit A - Site Diagrams 8/19/2015 Consent Decree
Consent Decree 8/19/2015 Consent Decree
Consent Decree Exhibit E 5/27/2015 Consent Decree
Consent Decree Exhibit D 5/27/2015 Consent Decree
Consent Decree Exhibit C 5/27/2015 Consent Decree
Consent Decree 5/27/2015 Consent Decree
Consent Decree Exhibit A 5/26/2015 Consent Decree
Agreed Order for RI/FS 5/26/2011 Agreed Order
Public Information 5
Document Title Document Date Document Type
Fact Sheet - Spanish 5/27/2015 Fact Sheet\Public Notices
Fact Sheet - English 5/27/2015 Fact Sheet\Public Notices
Response to Comment on Agreed Order 5/23/2011 Responsiveness Summary
Fact Sheet: Sudbury Road Landfill Agreed Order Comment Period - Spanish 4/1/2011 Fact Sheet\Public Notices
Fact Sheet: Sudbury Road Landfill Agreed Order Comment Period - English 4/1/2011 Fact Sheet\Public Notices
State Environmental Policy Act 1
Document Title Document Date Document Type
DNS and SEPA Checklist 6/1/2015 SEPA Documents
Technical Reports 36
Document Title Document Date Document Type
Sudbury Landfill Periodic Review 2022 7/5/2022 Periodic Review (5 Year)
SBRL OM Manual 4/14/2017 Operation and Maintenance Plan
Appendix A.5 4/14/2017 Operation and Maintenance Plan
Appendix A.4 4/14/2017 Operation and Maintenance Plan
Appendix A.3 4/14/2017 Operation and Maintenance Plan
Appendix A.2 4/14/2017 Operation and Maintenance Plan
Appendix A.1.c 4/14/2017 Operation and Maintenance Plan
Appendix A.1.b 4/14/2017 Operation and Maintenance Plan
Appedix A.1.a 4/14/2017 Operation and Maintenance Plan
Operation and Maintenance Plan 4/14/2017 Operation and Maintenance Plan
Construction Quality Assurance Certification Report 4/14/2017 Final Cleanup Action Report
Engineering Design Report for Sudbury Landfill Remedial Action 1/6/2016 Engineering Design Report
Construction Plans and Specs - Vol III CQA - Final 1/1/2016 Construction Plans and Specifications
Construction Plans and Specs - Vol II - Final 1/1/2016 Construction Plans and Specifications
Construction Plans and Specs - Vol I - Final 1/1/2016 Construction Plans and Specifications
Sudbury Road Landfill Draft Cleanup Action Plan 5/1/2015 Cleanup Action Plan
RIFS Final Draft Figure 3 10/3/2014 Remedial Investigation / Feasibility Study
Remedial Investigation and Feasibility Study Fact Sheet - Spanish 10/2/2014 Remedial Investigation / Feasibility Study
Remedial Investigation and Feasibility Study Fact Sheet - English 10/2/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 11 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 10 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 9 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 8 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 7 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 6 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 5 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 4 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 3 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 2 9/15/2014 Remedial Investigation / Feasibility Study
RIFS Final Draft App D 1 9/15/2014 Remedial Investigation / Feasibility Study
Remedial Investigation / Feasibility Study (RIFS) Final Draft 9/15/2014 Remedial Investigation / Feasibility Study
Cleanup Alternatives Analysis 11/8/2013 Feasibility Study
Remedial Investigation Work Plan 12/28/2011 Remedial Investigation Work Plan
Interim Action Plan 3/31/2010 Interim Action Documents
Historical Study Report 1/1/2006 Site Specific Technical Document - other
Sudbury Road Landfill Historical Study Report 1/1/2006 Independent Reports
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 5

Contaminant Type
Soil
Groundwater
Surface Water
Air
Sediment
Bedrock
Halogenated Organics - Halogenated Organics C
Metals - Metals - Other S
Other Contaminant - Conventional Contaminants, Organic S
Other Contaminant - Conventional Contaminants, Inorganic C
Other Contaminant - Other Deleterious Substances 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.