Washington Water Power Central Steam Plant

Facility Site ID: 726 Cleanup Site ID: 682

Cleanup Complete

The site was built in 1915 to burn coal and produce steam and electric power. In the mid-1960s, the boilers were converted to use petroleum (Bunker C). Seven underground storage tanks were constructed to store fuel.

Petroleum for the boilers spilled in 1982. Investigations found petroleum in soil and shallow groundwater. The contaminated groundwater is not a source of drinking water and is not connected to the Spokane-Valley Rathdrum-Prairie Aquifer.

Cleanup included excavating contaminated soil near the ground surface and replacing it with clean soil, capping the area with asphalt, and removing the underground storage tanks. A restrictive covenant is on the property, prohibiting the use of groundwater and any activities that would expose remaining contaminated soil.

Quarterly groundwater monitoring began in 1997. Gasoline- and diesel-range petroleum concentrations have met state standards since February 2005. However, petroleum continues to be removed from extraction wells. Bunker C continues to be detected at low concentrations in some groundwater monitoring wells. The site is now retail stores, restaurants, hotels, and commercial parking lots.

Periodic reviews

During the periodic reviews in 2023 and 2014, Ecology decided the cleanup continues to protect people and the environment. No repair, maintenance, or further cleanup were required.

During the periodic review in 2008, Ecology found a monitoring well on the eastern side of the intersection of South Lincoln Street and West First Avenue was missing the monument lid and well casing cap. The well was properly closed in 2010 to prevent potential groundwater contamination.

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 #: 4174187
County Recording Date: 12/30/1997


  • Restrict All Ground Water Extraction/Well Installation
  • Restrict Land Use

Restricted Media

  • Groundwater
  • Soil
Legal 3
Document Title Document Date Document Type
Washington Water Power Central Steam Plant - Consent Decree 11/21/1996 Consent Decree
Washington Water Power Central Steam Plant - Restrictive Covenant 10/7/1996 Environmental Covenant; Alternative Mechanism
Washington Water Power Central Steam Plant - Consent Decree 10/31/1994 Consent Decree
Public Information 1
Document Title Document Date Document Type
Washington Water Power Central Steam Plant - Fact Sheet Periodic Review Comment 12/1/2008 Fact Sheet\Public Notices
Technical Reports 7
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 1

Contaminant Type
Surface Water
Non-Halogenated Organics - Petroleum Products-Unspecified C C
Confirmed Above Cleanup Levels
Below Cleanup Levels
This contaminant list was based on our best information at the time it was entered. It may not reflect current conditions at the site.