Sierra Zinc Mine
Facility Site ID:
1786484
Cleanup Site ID:
1838
Site Description
The site is the location of former lead and zinc mining and milling operations. Remnants of ore milling operations include a 25-acre tailings impoundment containing about 88,000 cubic yards of contaminated soils and mine waste.
Mining operations began at the site in 1889 and continued sporadically through the mid- to late 1970s. Lead and zinc ore deposits were mined at the site using underground mining techniques. The mill was first built in 1941 and was expanded in 1949 to process as much as 500 tons of ore per day. The mill operated sporadically through the 1960s, however, little information is known about production totals.
Mining operations began at the site in 1889 and continued sporadically through the mid- to late 1970s. Lead and zinc ore deposits were mined at the site using underground mining techniques. The mill was first built in 1941 and was expanded in 1949 to process as much as 500 tons of ore per day. The mill operated sporadically through the 1960s, however, little information is known about production totals.
What's Been Done
Site investigations were conducted by the United States Environmental Protection Agency (EPA), Washington State Department of Natural Resources (DNR), and Resource and Environmental Management Consultants, Inc. (RMC) on behalf of The Goldfield Corporation.
Based on findings from the site investigations, removal actions were completed at the site between 2014 and 2016 that included excavating contaminated soils, tailings, and waste rock and disposing materials in the on-site tailings impoundment area. The demolition of the mill and administrative building was included as part of the removal action. The tailings impoundment was then covered with a 9-inch eco-barrier consisting of gravel, 18 inches of cover soil, and 6 inches of topsoil.
Following the removal action, institutional controls in the form of an environmental covenant was recorded with Stevens County to restrict certain activities and uses that interfere with the cleanup.
Based on findings from the site investigations, removal actions were completed at the site between 2014 and 2016 that included excavating contaminated soils, tailings, and waste rock and disposing materials in the on-site tailings impoundment area. The demolition of the mill and administrative building was included as part of the removal action. The tailings impoundment was then covered with a 9-inch eco-barrier consisting of gravel, 18 inches of cover soil, and 6 inches of topsoil.
Following the removal action, institutional controls in the form of an environmental covenant was recorded with Stevens County to restrict certain activities and uses that interfere with the cleanup.
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.
Institutional Controls 1
Environmental Covenant
County Recording #:
20170008437
County Recording Date:
11/22/2017
Restrictions/Requirements
- Ongoing Maintenance of Remedy
- Restrict Access
- Restrict Land Use
Restricted Media
- Soil
Documents 6
Legal 1
| Document Title | Document Date | Document Type |
| Sierra Zinc Mine - Environmental Covenant_Arrington | 11/22/2017 | Environmental Covenant; Alternative Mechanism |
Technical Reports 5
| Document Title | Document Date | Document Type |
| Sierra Zinc Mine - Periodic Review Notice - Nixon | 9/3/2024 | Site Specific Administrative Document - other (Administrative correspondence) |
| Sierra Zinc Mine - Periodic Review Notice - Pierce | 9/3/2024 | Site Specific Administrative Document - other (Administrative correspondence) |
| Sierra Zinc Mine - 2024 Periodic Review | 7/1/2024 | Periodic Review (5 Year) |
| Sierra Zinc Mine - Ecology Review of Draft Access Easement Agreement | 6/26/2023 | Site Specific Administrative Document - other (Administrative correspondence) |
| Sierra Zinc Mine and Mill Completion Report | 11/20/2015 | Remedial Action/As-Built 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
-
Central Regional Office1250 W Alder StUnion Gap, 98903-0009Please schedule an appointment to view print documents at this location.
Contaminants 1
| Contaminant Type | Soil |
Groundwater |
Surface Water |
Air |
Sediment |
Bedrock |
|---|---|---|---|---|---|---|
| Metals - Metals Priority Pollutants | C | C |
- 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.
Public Comment Period
Comments will be accepted September 4, 2024 through October 4, 2024.
You may submit your comments online or by mail to Justin Rice, Periodic Reviewer, at Ecology's Central Regional Office.
We complete a periodic review about every five years cleanup construction is complete at a site when institutional controls are part of the cleanup. The purpose of the review is to make sure the controls remain effective and the cleanup still protects human health and the environment.
We will review comments received during the comment period and make recommendations for suggested changes. The periodic review will become final if no significant changes are made. An additional public comment period will be held if significant changes are made.