06/23/2002

By AP Staff

Since miners pulled the last flask of mercury in 1958 from the Horse Heaven Mine in Jefferson County, the site has seen several owners but little environmental cleanup.

Today the mine is a priority for cleanup by the Oregon Department of Environmental Quality. And it's not alone.

Piles of mine rubble known as tailings are testimony to the once-active mining that took place as mercury from the mine was sent to separate gold dust from powdered quartz in the state's gold mines that flourished in the 1800s. It was later used in industry.

Mercury deposits likely still exist underground, and officials say mercury contamination is occurring.

Horse Heaven is one of about 40 abandoned mine sites in Central Oregon, some of which leach chemicals into the ground and threaten animal or human health, said Jeff Christensen of the DEQ.

Although officials have done only preliminary tests for a few mines, they know that certain sites such as Horse Heaven and the recently cleaned-up Mother Lode Mine in Crook County have mercury contamination.

Unless owners or "responsible parties" can be found, the state bears the burden of cleanup, which could reach into the tens of millions of dollars, said Christensen.

Left on their own, they can create "acid mine drainage," a process that occurs when rock material mixes with water or oxygen and makes groundwater and surface water more acidic.

Pollution from mines west of the Cascades has raised mercury levels in fish, Christensen said.

Bob Danko, policy analyst with the DEQ, said pollution caused by abandoned mines in Oregon pales in comparison to Rocky Mountain states.

Nonetheless, the state has begun analysis on mine sites throughout Oregon hoping to create a priority list for cleaning them up.

To date, the DEQ has identified 143 mines for potential action.

Of the mine sites in Central Oregon, 22 never produced one flask of mercury. Many of the sites were claims that never made it past the paperwork.

Much of the mercury mining in Oregon took place prior to the environmental movement, said Gary Lynch, assistant director of the Oregon Department of Geology and Mineral Industries.

A 1972 law required the reclamation of coal mines and laid a foundation for future environmental regulations of mining, he said.

Mine owners in Oregon, however, rarely cleaned up the sites they left.

In December, the Oregon Environmental Council released a report saying human activities, including abandoned mines, pump up to 5 tons of mercury into the environment each year.

The group has called for cleaning all abandoned mine sites.

While officials agree, they say they need funding. Cleanup funds come from the Orphan Site Account, which usually receives $12 million each legislative session to clean up mines where no responsible party can be found.

That money funds cleanup at all orphan sites, not just mines, and officials struggle to stretch the budget. During the last legislative session, lawmakers allocated only about $4 million because of the budget shortfall.

Less than $1 million has gone to mine cleanup since 1991, when the creation of the Orphan Site Account was authorized.

The DEQ wants to create an account specifically for mines and to make the existing Orphan Site Account money more available for mine cleanup.

But they also caution that they could do more environmental harm by trying to clean up some abandoned mine sites. That is because mercury exists in two forms: stable and methylmercury.

Highly toxic methylmercury forms when stable mercury meets oxygen. In its stable form, mercury poses little risk in low quantities. But methylmercury accumulates in the environment, passes through the food chain and harms or kills those who consume it.

State laws mandate that officials weigh the risks when deciding whether to clean mines, Christensen said. Officials must determine the extent of contamination, the type of mercury and the potential for exposure, he said. In the case of the Horse Heaven Mine, officials have taken the first steps toward cleanup, collecting soil and water samples.

That began only after DEQ officials found a responsible party. Sunoco Inc. finally agreed last fall to take responsibility.

Records show Sunoco bought Sun Oil Company, which took over the mine in 1936. Until 1945, Sun Oil Company operated the mine, which reopened from 1955-1958.

The cleanup at Horse Heaven could last years.

(Copyright 2001 by The Associated Press. All Rights Reserved.)