MICA LANDFILL
WASHINGTON
EPA ID# WAD980511661
EPA Region 10
Spokane County
Mica

5th Congressional District

Other Names: Spokane Co Utilities Dept - Office, Spokane Co - Mica Landfill
Last Update: April, 2010

Hide details for Site DescriptionSite Description

The Mica Landfill site has been owned by Spokane County Utilities since 1972, and covers 65 acres near Mica, WA. Prior to 1991, the landfill was licensed by the State to handle hazardous, domestic, and industrial waste. Landfill operations ended in late 1991. Groundwater beneath the landfill is contaminated with volatile organic compounds (VOCs), heavy metals, and phenol. About 115 domestic water wells and two municipal wells are located within three miles of the site and serve approximately 4,000 people .

Site Responsibility: This site is being addressed through state and county actions.

NPL Listing HistoryDates
Proposed Date:10/15/1984
Removed Date:
Withdrawal Date:
Final Date:06/10/1986
Deleted Date:


Hide details for Threats and ContaminantsThreats and Contaminants

Media Affected: Groundwater, Soil & Sludges
Groundwater contains VOCs, heavy metals, and phenols. Leachate (liquid moving through the land fill masses) is contaminated with at least 20 regulated organic compounds along with inorganic ions and metals. People who might ingest or come into direct contact with contaminated groundwater and leachate might be at risk. The presence of explosive levels of methane gas generated at the landfill, represents additional threats to public health and the environment.


Hide details for Cleanup ProgressCleanup Progress

Between 1991 and 1994, Spokane County constructed a number of leachate collection trenches and three leachate collection ponds. These ponds are pumped out as needed and the leachate is conveyed to a local plant for treatment and disposal. Later, a Remedial Investigation/Feasibility Study (RI/FS) was prepared by Spokane County pursuant to a Consent Decree with the State. In 1995, Spokane County finished building a permanent cover system with two impervious barrier layers and gas collection/treatment. The performance of the cover system was reviewed after five years of operation and it was determined to be operating effectively. A Cleanup Action Plan was completed in which the interim action was selected as the final remedy. Ground water monitoring will continue until cleanup levels are achieved. The cleanup action will be reviewed at least every five years. The site was designated construction complete on February 12, 2002.


Show details for Regional ContactsRegional Contacts