Department of Environmental Quality

DEQ Home/ Land Quality/ Environmental Cleanup/ ECSI/ Site Summary Full Report

Environmental Cleanup Site Information (ECSI) Database Site Summary Full Report - Details for Site ID 1449, champion mine

This report shows data entered as of October 23, 2021 at 11:17:03 PM

This report contains site details, organized into the following sections: 1) Site Photos (appears only if the site has photos); 2) General Site Information; 3) Site Characteristics; 4) Substance Contamination Information; 5) Investigative, Remedial and Administrative Actions; and 6) Site Environmental Controls (i.e., institutional or engineering controls; appears only if DEQ has applied one or more such controls to the site). A key to certain acronyms and terms used in the report appears at the bottom of the page.

Note: DEQ may have posted online documents related to this site. If so, they would be available for viewing or downloading on ECSI Summary Page

Go to DEQ's Facility Profiler to see a site map as well is information on what other DEQ programs may be active at this site.

Site Photos

Click to View Photo Picture Date Caption Size
View Photo 06/26/2008 Acid mine drainage from the former Formosa Mine has led to a dead zone in the south fork of Middle Creek. 1597 Kb
View Photo 10/02/2007 An example of acid mine drainage from the former Formosa Mine site 1113 Kb

General Site Information

Site ID: 1449 Site Name: champion mine CERCLIS No: 001002616
Address: 31S/6W/S26b  
  County: Douglas Region: Western
Other location information: About 7 miles south of Riddle on the SW slope of Silver Butte.
Investigation Status: Listed on CRL or Inventory
  Brownfield Site: No NPL Site: Yes Orphan Site: Yes Study Area: No
Property: Twnshp/Range/Sect: 31S , 6W , 26 Tax Lots:
  Latitude: 42.8517 deg. Longitude: -123.3847 deg.  Site Size: 76 acres
Other Site Names:
  Silver Butte Mine

Site Characteristics

General Site Description:
Site History: The mine operated periodically during the 1900s, with the majority of production occurring between 1989 and 1994 under the ownership of Canadian mining company Formosa Explorations Inc. Copper and zinc was reported to have been produced at a rate of 350 to 400 tons per day.
Contamination Information: (3/12/2003 GA/SRS) When the mine closed in 1994, Formosa backfilled the mine workings with mill tailings, crushed ore, and limestone. Acid mine drainage (AMD) from the two adits was directed to a scree slope. Approximately 20,000 cubic yards of low-grade ore were placed into a lined cell at the site (referred to as the "encapsulation mound"). After the reclamation was completed, Formosa filed for bankruptcy. In 1997, it was discovered that the AMD control system had failed, and acidic wastes were discharging to Middle Creek and South Fork Middle Creek.
Manner and Time of Release: Release of acidic groundwater and runoff from abandoned mine.
Hazardous Substances/Waste Types: Acid mine drainage (primarily cadmium, copper, lead, and zinc).
Environmental/Health Threats: Acidic wastes from the Formosa Mine have discharged to Middle Creek and South Fork Middle Creek. Middle Creek is a tributary of Cow Creek, which is a source of drinking water for the City of Riddle. The two Middle Creeks are considered habitat for threatened Oregon Coast coho salmon and steelhead. Monitoring has indicated that 18 miles of the two creeks have been severely impacted by acid mine drainage from the Formosa Mine.
Status of Investigative or Remedial Action: (3/12/2003 GEA) In 1999, DEQ began working with the federal Bureau of Land Management (BLM) to investigate and clean up the site. BLM agreed to conduct a Remedial Investigation (RI) at the site. The RI was completed in May 2000. After declaring the mine an orphan site by DEQ in 2000, DEQ completed an interim removal action to address the acid mine drainage (AMD). The encapsulation mound was capped with a temporary plastic liner. AMD from the two adits was routed away from the headwaters of Middle Creek to a scree slope. (2/7/2005 GEA) DEQ and BLM completed the FS in January 2005.

(8/1/2019) - Bryn Thoms is PM, Greg Aitken retired.
Data Sources:

Substance Contamination Information

Substance Media Contaminated Concentration Level Date Recorded
CHROMIUM Other Adit Water dissolved chromium - .392 mg/L  
CHROMIUM Surface Water Dissolved Chromium - .006 mg/L  
COPPER Other Dissolved Copper - Adit water - 40.4 mg/L  
COPPER Surface Water Dissolved Copper - Surface Water (Middle Cr.) - 3.7 mg/L  
LEAD Other Dissolved Lead - Adit water - .015 mg/L  
LEAD Surface Water Dissolved Lead - Surface Water (Middle Cr.) - .007 mg/L  
ZINC Other Dissolved Zinc - adit Water - 137 mg/L  
ZINC Surface Water Dissolved Zinc - Surface Water (Middle Cr.) - 10.3 mg/L  

Investigative, Remedial and Administrative Actions

Action Start Date Compl. Date Resp. Staff Lead Pgm
SITE EVALUATION 10/23/1993 10/23/1993 Brian McClure SRS
Listing Review completed 10/24/1993 10/24/1993 Brian McClure SRS
Insufficient information to list 10/24/1993 10/14/2002 Brian McClure SRS
REMOVAL 10/25/1993 07/21/1994 Brian McClure SRS
Site added to database 11/02/1993   Brian McClure SRS
Refer to Program 07/21/1994 05/01/1999 WQ
REMEDIAL INVESTIGATION 05/01/1999 01/08/2003 Greg Aitken
PRELIMINARY ASSESSMENT EQUIVALENT 03/09/2000 07/26/2000 Karl Morgenstern SRS
REMOVAL ASSESSMENT 03/09/2000 09/22/2000 Karl Morgenstern SRS
ORPHAN SITE 03/22/2000   Greg Aitken SRS
REMOVAL 09/22/2000 11/12/2000 Karl Morgenstern SRS
Proposal for Inventory recommended 10/14/2002 10/14/2002 Greg Aitken VCP
Proposal for Confirmed Release List recommended 10/14/2002 10/14/2002 Greg Aitken VCP
Facility proposed for Confirmed Release List 02/04/2003 02/04/2003 Kimberlee Van Patten SAS
Facility proposed for Inventory 02/04/2003 02/04/2003 Kimberlee Van Patten SAS
Facility placed on Confirmed Release List 03/31/2003 03/31/2003 Kimberlee Van Patten VCP
Facility placed on Inventory 03/31/2003 03/31/2003 Kimberlee Van Patten VCP
FEASIBILITY STUDY 04/07/2004 01/15/2005 Greg Aitken ORP
Site added to CERCLIS 02/16/2005 02/16/2005
National Priorities List Site 09/19/2007   Greg Aitken ORP
REMEDIAL INVESTIGATION  (Primary Action) 06/26/2008   Bryn Thoms ORP

Key to Certain Acronyms and Terms in this Report:

You may be able to obtain more information about this site by contacting Bryn Thoms at the Western regional office or via email at If this does not work, you may contact Ximena Cruz Cuevas (503) 229-6811, or via email at or contact the Western regional office.