COQUILLE - Residents of the Seven Devils area near Bandon have sought to prevent development of a chromite mining operation for more than two years, with their latest argument focusing on how one of Oregon Resources Corp.'s own studies show a toxic substance is present in low levels in the company's wells.

Sharon Comden presented her evidence to Coos County commissioners. It was a 2008 report prepared by the URS Corp. on wells in the Whisky Run Beach area, which indicates hexavalent chromium is approaching the toxic level for aquatic species, but not for people drinking the water.

Oregon Resources Director of Geology Joseph Drew said tests did find the toxin, but at concentrations at about half the level that would harm fish.

Commissioners have hired their own geologist to study profitability of precious metals found in the mining holes.

"Monitoring well testing is a procedure I'm not familiar with," said Gold Beach geologist Russell Ralls. "The amount of natural hexavalent in place is probably not exorbitant."

But he admitted he is not an expert on the subject.

Opponents in the Bandon Woodlands Community Association that represents 250 neighborhood households have been talking with scientists to help make their case, said member Jack Jones. They include Dr. Chris Oze and the U.S. Geological Survey Senior Hydrogeochemist Dr. D. Kirk Nordstrom, along with Dr. Dan Bain and geo-hydrologist Greg Kupillas.

"They are concerned that the loss of soil structure and dispersion of groundwater during mining could release even higher levels of CrVI (hexavalent chromium) into our shallow groundwater," Jones said in a statement.

Ralls believes otherwise, saying the black sand in which the chromite is found has gone through a natural battering by the rivers and ocean over millions of years. The only way to create the hexavalent chromium is through exposure to acids or extreme heat.

That's not what ORC will do. Mining company officials said they'll separate the chromite, zircon and garnet from the sand using only centrifugal force and water - not heat or chemicals.

Ralls said houses in Bandon sit on black sand deposits - the same as those near the beach where Oregon proposes to explore.

"If it was toxic, we'd all be dead," he said.

The geologist made a presentation Friday in Coquille on the area's mining history and fielded questions about whether mining for minerals on ancient beach terraces would significantly disturb aquifers.

"There are limited connections between the bodies of water, because any fractures would not hold much water," Ralls said.

Commissioners hired Ralls for an initial consulting fee of about $600 to determine if Coos County could profit off precious metals in the ground.

"Right now we need money to staff our jail and other things," said commissioner Nikki Whitty.

Oregon Resources Chief Operating Officer Dan Smith said his company doesn't want those metals, which would be returned to the mining sites as tailings to fill bore holes.

"Unless the county wants to pay for its separation," he said.

Drilling could cost the county millions, and Smith said it would require another step and installation of special equipment at the plant to separate the metals.

"There are very small quantities of gold and platinum," Drew said, "and when we bring up the soil, it's difficult to separate."

By allowing ORC to mine county land, the county could make an estimated $32,000 a year in royalties per acre, Smith said.

Coos County Forester Bob Laport said, in the current market, timber harvests bring $15,000 to $30,000 an acre in annual revenue. He said timber money is guaranteed, but the mining company is only offering estimates at this time.

He warned that if he followed Oregon Resources' schedule, timber stands too young to create revenue would be cut down and old growth would have to be harvested for little revenue considering the bad market.

"My huge concern is, No. 1, keeping the integrity of county forests," Whitty said.