Pend Oreille Mine cleanup site, Metaline Falls

We visited the site August 10, 2023, and found the cleanup remains effective. Groundwater with manganese contamination and soil with metals contamination above state standards remain at the site, but they are contained following the requriements of the Cleanup Action Plan. 

Learn more

• Review the draft Periodic Review.
• Visit our Pend Oreille Mine cleanup site page.

Next steps

We will review all comments received during the comment period and update the periodic review, if needed. If no significant changes are made, the periodic review will become final. If significant changes are made, we will hold an additional public comment period. We will hold an online public meeting if 10 or more people request one.​​

Site history and cleanup

The Pend Oreille Mine, located in Northeast Washington approximately two miles north of Metaline Falls, began underground mining for lead and zinc in 1952. The mine operated intermittently and was closed for decades before Teck Washington Inc. reopened it in 2004.

Two tailings disposal facilities (TDFs), referred to as TDFs 1 and 2, that were used from 1967 and 1977 were cleaned up under the 2011 Cleanup Action Plan. The cleanup included regrading the piles to remove steep slopes and minimize erosion, compacting their surfaces, placing protective covers systems over the piles to prevent stormwater from carrying contaminants to groundwater, and manageingstormwater runoff.

The mine stopped operating in 2019. In April 2021, Teck announced a transition from care and maintenance status to closure. The formal closure of the Pend Oreille Mine requires close work between us and Teck to ensure all regulatory requirements are met, and the community is informed of the process.

About periodic reviews

Periodic reviews are required when institutional controls are required at a site. Institutional controls can be fences, signs, or restrictions on how the property is used. 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.