Gas Works Park WA Natural Gas
2000 N Northlake Way, Seattle, WA 98103

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Seattle Parks and Recreation (SPR) will be doing maintenance and renovations at the Play Area, Comfort Station, and Entry areas at Gas Works Park (details below) throughout Spring of 2017. At the same time as the renovations, Puget Sound Energy (PSE) will conduct additional studies of the contaminated groundwater, and install part of a system in the play area that will clean up contamination at the site. Ecology has reviewed and approved a work plan to do this work. 

Ecology held a public comment period from March 20- April 18, 2018. The documents can be found below:


Ecology also recently conducted a public comment period for a State Environmental Policy Act (SEPA) Determination of Non-Significance, which determined that no adverse environmental impact will result from this work. That comment period was complete on March 16, but you may still view the documents by following these links:


The additional studies are being done at this time to take advantage of the area being closed off to the public for renovations, rather than PSE having to do it in the future and close it off a second time. The work will also prevent additional contamination from reaching Lake Union before in-water cleanup begins.  It will also be a vital piece to the final overall cleanup at the park. SPR maintenance and renovation work will include installation of new play equipment in the children’s play area. The new equipment will meet updated safety standards and the play area and access to the play area will be improved to comply with Americans with Disabilities Act (ADA) requirements. The east entry access will also be improved to meet ADA requirements. SPR will also demolish the existing comfort station and build a new facility in the same location. All improvements and associated repaving work will provide better access to and through the area around the play barn consistent with ADA requirements. 

Arsenic in soil and groundwater

Elevated concentrations of arsenic were detected in soil and groundwater samples collected from beneath the Play Area during the 2013 supplemental upland investigation (GeoEngineers, 2013). Information obtained during the first supplemental investigation in 2014 was used to refine the understanding of the nature and extent of subsurface arsenic in this area. Arsenic is a concern for groundwater below the surface of the park.  There is no risk to park users of coming into contact with the arsenic. 

Recent Monthly Progress Report 

Kite Hill Maintenance
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Ecology oversees work at Gas Works Park to ensure previous cleanups continue to protect human health and the environment and are consistent with the existing legal agreements (Consent Decree and Agreed Order) between Ecology, Parks and PSE. 

The park uplands underwent environmental cleanup actions in 2000/2001, 2005 and 2012. A cap of up to two (2) feet of clean topsoil and a geotextile fabric as an indicator were placed over the contaminated soil below. Between 2001 and 2006, soil and groundwater were cleaned up in the SE corner of the park. The work completed last year will maintain the integrity of the cap on Kite Hill. The work is being done before the in-water cleanup of contaminated sediment which is expected to begin in late 2018.

Gas Works Park Update Fact Sheet, August 2014



The Environmental Protection Agency (EPA) has developed a new environmental justice (EJ) mapping and screening tool called EJSCREEN. It is based on nationally consistent data and an approach that combines environmental and demographic indicators in maps and reports. See below for information about demographics in the area of Gas Works Park, Seattle.

EJSCREEN Census Block Map - This shows the Census Blocks used to generate the reports below.

EJSCREEN ACS Summary Report Gas Works Park – This shows the demographic information about the population of the area.

EJScreen Report Gas Works Park – This report shows the values for environmental and demographic indicators and EJSCREEN indexes. These percentiles provide perspective on how the selected block group or buffer area compares to the entire state, EPA region, or nation.
You can also check What’s in My Neighborhood to find out about other cleanups in your area. 

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Gas Works Park is a 20-acre park located at 2101 North Northlake Way.  The park extends into Lake Union (the lake lies to the east, west and south of the park).  The park’s north end is bounded by Northlake Way.
From the early 1900s until 1956, gas companies operated a plant at the site that converted coal and oil into manufactured gas.  A tar refinery also operated at the site, refining materials obtained as a by-product of the gas manufacturing process, and producing coal tar-based products. 
The Gas Works Park uplands underwent an environmental cleanup in 2000 and 2001, in which two feet of clean topsoil was placed over a protective barrier.  A groundwater remediation system was installed and operated from 2001 through 2006.
Sediment investigations offshore of Gas Works Park in Lake Union have indicated the presence of high levels of polycyclic aromatic hydrocarbons (PAHs).  The City of Seattle and Puget Sound Energy are conducting Remedial Investigations and Feasibility Studies for these contaminated sediments. 
The purpose of these investigations and studies is to identify the nature and extent of contamination present and to evaluate potential cleanup solutions.  The Hydrogeological Investigation supports the development of cleanup actions  for sediment of the site.


For a complete list of documents please see "View Electronic Documents" on the right.



Map showing site location as King County, WA SITE INFORMATION


View Electronic Documents

Site Summary Report

Facility Site ID: # 139

Cleanup Site ID: 2876

Seattle, King County

Status: Cleanup Started   Get definitions of Status terminology

Ching-Pi Wang
Site Manager
(425) 649-7134

Brad Petrovich
Public Involvement Coordinator
(425) 649-4486

Document Repositories:

Northwest Regional Office
3190 160th Ave SE
Bellevue, 98008-5452

Fremont Public Library
731 N 35th Street
Seattle, 98103