Facility Site ID: 8786341
Cleanup Site ID: 3380

Oct. 2
8:00 am
Nov. 3
11:59 pm

Public Comment Invited On Removal From Contaminated Sites List

Contamination at WA DNR Webster Nursery is now below cleanup levels, and Ecology is ready to remove this site from the Contaminated Sites List. We will consider public input before making a final decision.

Some contaminated soil deep in the ground was left behind during cleanup. An Environmental Covenant filed with Thurston County sets rules to prevent people and wildlife from being exposed to this contamination. 

Submit your comments between October 2nd at 8:00 AM and November 3rd at 11:59 PM. More information about this comment opportunity is in the fact sheet

Current Status

A map showing the location of WA DNR Webster Nursery in Tumwater
A map showing the location of WA DNR Webster Nursery in Tumwater

The Washington State Department of Natural Resources (WA DNR) did cleanup work at this site in 1996 and 2018. Cleanup included removing the source of contamination (a leaking, underground storage tank full of pesticides) and a total of 215 cubic yards of contaminated soil. Some contaminated soil deeper in the ground was left behind during cleanup for structural stability of the warehouse.

Groundwater monitoring wells showed that contamination never left the property.

After the 2018 cleanup, six years of quarterly groundwater testing showed that groundwater contamination dropped below cleanup levels. Ecology determined that no more cleanup is necessary. The site is ready to be removed from the Contaminated Sites List. Because some contamination was left behind, Ecology required WA DNR to file an Environmental Covenant with Thurston County.

An Environmental Covenant sets rules to prevent people and wildlife from being exposed to the contamination that was left behind. For example, the property can never be used for schools, childcares, homes, growing food, or grazing animals. Also, Ecology must review and approve before any activities that could disrupt soil in the excavated area. Ecology will conduct a periodic review for this site about every five years to make sure the rules in the Environmental Covenant are being followed.

Ecology is holding a public comment period from October 2nd to November 3rd, 2025, to gather public input on removing the site from the Contaminated Sites List.

Site Description

The underground storage tank was beside the warehouse building (pictured) in the southeast corner of the nursery property.  The warehouse building is currently used to store equipment and rock cores.
The underground storage tank was beside the warehouse building (pictured) in the southeast corner of the nursery property. The warehouse building is currently used to store equipment and rock cores.

Webster Nursery is a 300-acre tree nursery run by the Washington State Department of Natural Resources (WA DNR). The nursery grows and sells 9 million seedlings each year. The nursery uses herbicides and fungicides to control weeds and protect seedlings from disease. 

In the past, the nursery used organochlorine pesticides, including chlordane and heptachlor. These chemicals were very effective at killing insects but are also toxic to human health. The nursery has not used insecticides since the early 1990s.

Ecology added this site to the Contaminated Sites List because an underground storage tank leaked pesticides into soil and groundwater.

Cleanup History

A photo of workers excavating contaminated soil in 2018.
A photo of workers excavating contaminated soil in 2018.

1978: WA DNR built a 40-feet wide by 180-feet long pesticide storage warehouse. The building included floor drains that were connected to a 750-gallon, concrete, underground storage tank (UST) that was located a few feet south of the building. The building was designed and constructed to have three areas for different purposes. The southern portion was used for barrel, mulch, and peat storage. The middle portion was used for seed and fertilizer storage, and the northern portion was used as a chemical storage area. The chemical storage area included two central floor drains plus a floor drain for a shower and a service sink.

1982: WA DNR replaced the concrete UST with a steel UST.

1996: WA DNR found that the steel UST was leaking and full. WA DNR removed the UST and 70 cubic yards of contaminated soil (about 7 dump trucks full). It was not possible to remove all of the contaminated soil because of the structural stability of the warehouse, and groundwater seeping into the excavation hole. Contaminated soil and water were taken offsite for proper recycling and disposal. Soil around the drains and pipes were tested and did not have any contamination. Available information indicates that the sink and shower within the chemical storage portion of the warehouse were the most likely source of the pesticide contamination that went into the tank.

1997: Thurston County Health Department and Washington State Department of Health sampled public wells in 1997. They did not detect pesticides above lab reporting limits and concluded that the water was safe.

1998: Ecology and WA DNR entered an agreement to investigate the extent of contamination, consider cleanup alternatives, and develop a cleanup plan.

2001: Ecology and WA DNR entered into an agreement to finalize the cleanup plan, monitor the site, and prevent water from moving through the contaminated area.

2001-2016: Yearly groundwater monitoring showed heptachlor epoxide concentration in groundwater near the former UST was above the state cleanup level.

2014: WA DNR tested soil and groundwater to find the extent of contamination.

2016: Ecology and WA DNR entered into an agreement to remove more contaminated soil and monitor groundwater. The cleanup work was delayed to 2018 because of state budget issues.

2018: WA DNR removed about 145 cubic yards (about 14 dump trucks full) of contaminated soil, backfilled with clean soil, and covered it with grass. Not all the contaminated soil could be removed due to structural constraints.

2018-2024: WA DNR monitored groundwater quarterly to make sure that the 2018 soil excavation was an effective cleanup.

2025: After reviewing six years of groundwater data, Ecology proposes removing the site from the Contaminated Sites List and an Environmental Covenant was recorded with Thurston County.

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 #: 3336349
County Recording Date: 2/15/2001

Restrictions/Requirements

  • Prevent the Reuse or Relocation of Site Soil
  • Prohibit Soil Disturbance
  • Restrict All Ground Water Extraction/Well Installation
  • Restrict Land Use

Restricted Media

  • Groundwater
  • Soil

Environmental Covenant

County Recording #: 5063082
County Recording Date: 7/10/2025

Restrictions/Requirements

  • Prohibit Soil Disturbance
  • Restrict Land Use

Restricted Media

  • Soil
Legal 7
Document Title Document Date Document Type
Covenant 5063082 7/10/2025 Environmental Covenant
WA DNR Webster Nursery - EC (unrecorded) 5/29/2025 Environmental Covenant
2016 Agreed Order with Cleanup Action Plan 7/7/2016 Agreed Order
DNR Webster Nursery Final PLP Letter 6/14/2016 Final Potentially Liable Person Status Letter
Restrictive Covenant-Dept. of Natural Resources/Webster Nursery 2/15/2001 Environmental Covenant; Alternative Mechanism
Agreed Order No. DE 00 TCPSR-295 1/8/2001 Agreed Order
WA DNR Webster Nursery Agreed Order July 1999 7/1/1999 Agreed Order
Outreach Information 5
Document Title Document Date Document Type
Public Comment Period on Removal from Contaminated Sites List 10/2/2025 Fact Sheet\Public Notices
DNR Webster Nursery Construction Progress Update 7/25/2018 Fact Sheet\Public Notices
2016 AO Responsiveness Summary 9/8/2016 Responsiveness Summary
2016 AO, FS, dCAP, SEPA Factsheet 6/29/2016 Fact Sheet\Public Notices
Public Participation Plan 6/6/2016 Public Participation Plan
State Environmental Policy Act 1
Document Title Document Date Document Type
WA DNR Webster Nursery SEPA checklist and DNS 7/6/2016 SEPA Documents
Technical Reports 45
Document Title Document Date Document Type
SHARP 7/7/2025 Site Hazard Assessment and Ranking Process Report
WA DNR Webster Nursery - Sub-Slab Soil Investigation Report Approval 12/10/2024 Site Specific Administrative Document - Other (Administrative Correspondence)
WA DNR Webster Nursery - Sub-Slab Soil Investigation 10/8/2024 Remedial Investigation Report
WA DNR Webster Nursery Sub-Slab Soil Investigation Report Review, Third Quarter 2023 Groundwater Monitoring Results Review, and Next Steps at the Site 10/2/2024 Site Specific Administrative Document - Other (Administrative Correspondence)
WA DNR Webster Nursery - Sub-Slab Investigation Work Plan 4/4/2024 Remedial Investigation Work Plan
WA DNR Webster Nursery Sub-Slab Soil Investigation Work Plan Approval 4/3/2024 Site Specific Administrative Document - Other (Administrative Correspondence)
WA DNR Webster Nursery Sub-Slab Soil Investigation Work Plan Comments 2/22/2024 Site Specific Administrative Document - Other (Administrative Correspondence)
WA DNR Webster Nursery - Third Quarter 2023 Groundwater Monitoring Results 11/2/2023 Monitoring Report
WA DNR Webster Nursery - Compliance Monitoring Plan Approval 6/14/2023 Site Specific Administrative Document - Other (Administrative Correspondence)
WA DNR Webster Nursery - Compliance Monitoring Plan 4/14/2023 Monitoring Plan
WA DNR Webster Nursery - Third Quarter 2022 Groundwater Monitoring Results 10/12/2022 Monitoring Report
WA DNR Webster Nursery - Second Quarter 2022 Groundwater Monitoring Results 7/29/2022 Monitoring Report
WA DNR Webster Nursery - First Quarter 2022 Groundwater Monitoring Results 4/5/2022 Monitoring Report
WA DNR Webster Nursery - Fourth Quarter 2021 Groundwater Monitoring Results 1/13/2022 Monitoring Report
Third Quarter 2021 Groundwater Monitoring Results, Webster Nursery Site 10/8/2021 Monitoring Report
Second Quarter 2021 Groundwater Monitoring Results, Webster Nursery Site 6/15/2021 Monitoring Report
First Quarter 2021 Groundwater Monitoring Results, Webster Nursery Site 4/30/2021 Monitoring Report
WA DNR Webster Nursery - Notice of Change of Coodinator 3/23/2021 Site Specific Administrative Document - Other (Administrative Correspondence)
Fourth Quarter 2020 Groundwater Monitoring Results 1/29/2021 Monitoring Report
Third Quarter 2020 Groundwater Monitoring Results, Webster Nursery Site 10/16/2020 Monitoring Report
Compliance Monitoring Plan, Webster Nursery Site 8/11/2020 Monitoring Plan
Second Quarter 2020 Groundwater Monitoring Results, Webster Nursery Site 7/1/2020 Monitoring Report
WA DNR Webster Nursery - Cleanup Action Completion Report 5/29/2020 Remedial Action Report
WA DNR Webster Nursery - First Quarter 2020 Groundwater Monitoring Results 4/19/2020 Monitoring Report
Fourth Quarter 2019 Groundwater Monitoring Results, Webster Nursery Site 1/13/2020 Monitoring Report
Third Quarter 2019 Groundwater Monitoring Results, Webster Nursery Site 10/16/2019 Monitoring Report
May 2019 GW Monitoring Report 7/3/2019 Monitoring Report
February 2019 GW Monitoring Report 4/18/2019 Monitoring Report
August 2018 GW Monitoring Report 2/21/2019 Monitoring Report
November 2018 GW Monitoring Report 2/21/2019 Monitoring Report
Webster Nursery - CPM Change Letter 11/1/2018 Site Specific Administrative Document - Other (Administrative Correspondence)
September 2017 Groundwater Monitoring Results 11/9/2017 Monitoring Report
Remedial Action Work Plan, Webster Nursery, 9805 Blomberg Street SW, Tumwater, WA 10/31/2017 Engineering Design Report
WA DNR Webster Nursery draft Cleanup Action Plan 6/6/2016 Cleanup Action Plan
WA DNR Webster Nursery Feasibility Study 6/6/2016 Feasibility Study
September 2014 Semiannual Groundwater Monitoring, Webster Nursery Site 12/5/2014 Monitoring Report
Subsurface Investigation Results, Webster Nursery Site 7/30/2014 Remedial Investigation Report
Subsurface Investigation Activities Work Plan, Webster Nursery Site 4/16/2014 Remedial Investigation Work Plan
February 2014 Semiannual Groundwater Monitoring, Webster Nursery Site 3/27/2014 Monitoring Report
September 3-4, 2013 DNR Webster Nursery Groundwater Sampling Event 11/26/2013 Monitoring Report
August 13 - 15, 2012 DNR Webster Nursery Groundwater Sampling Event 10/11/2012 Monitoring Report
WA DNR WEBSTER NURSERY Site Hazard Assessment 2/1/1999 Site Hazard Assessment Report
WA DNR Webster Nursery - Work Plan, Pesticide Storage Warehouse, Webster Nursery 1/1/1999 Remedial Investigation Work Plan
DNR-Webster Nursery Project Update 9/30/1997 Monitoring Report
Private Well Sampling near DNR Webster Nursery 5/28/1997 Monitoring Report
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

  • Southwest Regional Office
    300 Desmond Dr SE
    Lacey, 98503-1274
    Please schedule an appointment to view print documents at this location.
  • Tumwater Timberland Library
    7023 New Market Street SW
    Tumwater, 98501
    This location may only have print documents available during open comment periods.

Contaminants 1

Contaminant Type
Soil
Groundwater
Surface Water
Air
Sediment
Bedrock
Pesticides - Pesticides-Unspecified RA 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.