Land Quality Division 

Environmental Cleanup 

& Emergency 

Response Section

811 SW 6th Avenue

Portland, OR 97204

Phone: (503) 229-5512

(800) 452-4011

Fax: (503) 229-5850

Contact: Gil Wistar

www.oregon.gov/DEQ

Last Updated: 9/4/12

By: Gil Wistar

12-LQ-032

Cleanups of Abandoned Mines in 

Oregon Complicated by High Cost 

and Lack of Funding

This fact sheet describes challenges posed by 

abandoned and inactive hard rock mines in

Oregon, and outlines the Oregon Department of 

Environmental Quality’s approach to cleaning 

up mines that are a high risk to human health 

and to our land and water quality.

Oregon has hundreds of abandoned and inactive metal 

mines and some pose environmental risks to the public.

Legacy mining sites

Abandoned and inactive mines are found 

throughout the state, including historic mining 

districts in eastern and southwest Oregon and in 

the Willamette Basin. Over the last century,

minerals and metals such as gold, silver, 

copper, zinc, and mercury have been extracted 

from these mines. State and federal agencies 

have identified over 150 mines in Oregon that 

may need further investigation or cleanup. 

About 95 have undergone at least initial 

assessment. Some mines are on public lands 

such as national forests and land managed by 

the federal Bureau of Land Management

(BLM). Others are located on private land. A 

few mines are located on both public and 

private land.

Public health and environmental effects

Some abandoned mines have caused acid mine 

drainage, which can contaminate drinking 

water, expose people to toxic mine wastes, and 

degrade habitats for threatened and 

endangered fish. These problems sometimes 

occur far downstream from the mine sites. 

For example, mercury released from 

abandoned mines in the upper Willamette 

Basin has increased mercury levels in fish 

caught in downstream reservoirs, resulting in 

fish-consumption advisories for anglers.

DEQ’s approach to abandoned mines

DEQ normally relies on responsible parties, 

such as property owners or operators, to pay 

for cleanup of contaminated sites. But past 

operators of abandoned mines often cannot 

be found or made to pay for cleanup. In many 

cases, subsequent abandoned mine owners 

are also unable to pay the typically large 

costs required to clean up these sites.

DEQ uses a limited state fund called the 

Orphan Site Account (OSA) to clean up

contaminated sites, including abandoned 

mines, where responsible parties are either 

unknown – or unable or unwilling – to pay 

for cleanup. Decreased OSA funding has 

forced DEQ to focus on mines posing the 

greatest human health risk, with an emphasis 

on stabilizing sites and preventing high-risk 

human exposure to contaminants (e.g., 

treating or replacing contaminated drinking 

water). The decreasing availability of OSA 

funds requires that DEQ delay the cleanup of 

other “orphan sites” that may not be causing 

immediate or severe threats to human health.

For abandoned mines, these constraints mean 

that DEQ will continue to:

• Prioritize sites based on risks posed to human 

health and the environment, assigning highest 

priority to direct threats to human health;

• Limit the use of OSA funds to stabilize sites 

and reduce human exposure to contaminants;

• Work closely with federal agencies (BLM, the 

U.S. Environmental Protection Agency, and 

the U.S. Forest Service) to secure cleanup 

funds for sites located on both public and 

private land.

Fact Sheet
Abandoned mine sites DEQ has worked 

on, but have insufficient funding

Examples of abandoned mines that are orphan 

sites (or orphan caliber) but have insufficient 

funding available to complete cleanup include:

Bonanza Mine (Douglas County)

This historic mercury mine operated primarily 

between 1930 and 1960 on private property 

east of Sutherlin. Elevated levels of arsenic and 

mercury have been detected in soil, and arsenic 

is also in well water near five residences at or 

near the site. DEQ has spent over $390,000 to 

investigate the site and remove highly

contaminated soil around the former mill

portion of the mine. The Oregon Health 

Authority has assessed mercury and arsenic 

exposures of nearby residents, determining that 

levels are within a normal range. In the absence 

of significant human health risks and after

removal of the most contaminated soils, DEQ 

has postponed further cleanup in favor of work 

needed at higher priority orphan sites.

Historically, tailings from Bonanza Mine were 

used to construct roads throughout the Sutherlin 

area. An example is a road built on a 17-mile

former railroad bed, which runs through public 

and private property in the Sutherlin area.

Known as Red Rock Road, this road is

contaminated with mercury and arsenic, and its 

contaminant profile is very similar to Bonanza 

Mine. DEQ has used limited orphan funds on 

Red Rock Road to supplement cleanup work 

done by Weyerhaeuser Co., the historic owner 

of one section of the road.

Golconda Mine (Baker County)

Heavy metal discharges from this historic gold 

mine near Sumpter are entering a tributary of 

Silver Creek and Cracker Creek, both of which 

provide habitat for threatened bull trout species. 

There are several open mine shafts, adits, and 

pits that pose risks to site visitors. DEQ has 

completed a site investigation and removal 

assessment, and has partially stabilized the site 

to prevent exposure to physical hazards. Lack 

of funding will limit further actions in the near 

term. Physical hazards and public access 

remain the most direct human-health threats.

Opalite Mine (Malheur County)

Opalite Mine is an inactive mercury mine about

15 miles northwest of McDermitt, Nevada. The 

site consists of several open mine shafts, adits, 

and pits that pose risks to site visitors. The 

site also has remains of processing facilities, 

and two large piles of processed ore. 

Sampling at the site has identified high 

concentrations of mercury in soil, sediment, 

and fish tissue. Consistent with other 

abandoned mine sites, tailings from Opalite 

and the adjacent Bretz Mine were used to 

construct roads in the area – and may have 

contaminated approximately 15 miles of 

road. DEQ has used limited OSA funds on 

the site to supplement cleanup work done by 

EPA and BLM. As with Golconda Mine, 

physical hazards and public access remain 

the most direct risks to human health.

Tailings piles and former processing facilities at 

Opalite Mine.

Alternative Formats

Alternative formats of this document can be 

made available. Contact DEQ’s Office of 

Communications & Outreach for more 

information at (503) 229-5696.