MINTURN - Melissa MacDonald stands on a rock beside the Eagle River below Gilman and points out where water used to run in a more cappuccino-like hue and the rocks looked like someone painted them orange as a Halloween prank.After many years of Eagle Mine cleanup - cleanup of contaminants such as arsenic, cadmium, copper, lead and zinc - the river is pretty healthy, she said."It's pretty good. It meets the existing standard for the river," said MacDonald, executive director of the Eagle River Watershed Council. "We'd like a little higher standard, but currently they're doing a good job.""They" are CBS, the media company, formerly Viacom. They acquired the Eagle Mine in the mid-1980s as part of some other deal.What they acquired was a Superfund site, designating the Eagle Mine as one of the nation's most polluted places.Greg Caretto said when he started Nova Guides in 1984, the tailings pile was 25 feet high and covered dozens of acres in a meadow at the base of Tennessee pass.Now, the cleanup, which was ordered by the Environmental Protection Agency, is complete. The developers who want to build the Battle Mountain private ski area said they are waiting for the EPA to give them the green light to build homes where that tailings pile used to be."CBS has spent millions to clean this up and they've done a good job," said David Heinze with Environ International, the firm that runs the wastewater treatment plant that cleans the water from the mine.The Eagle River Watershed Council was one of several organizations collecting data about the river's health. Most data used to be depressing.Now, not so much."You learn year-to-year (by) studying bugs. Over time, you learn by looking at fish," said Seth Mason with the Watershed Council.Clean water conundrumPeople can consume zinc - fish, on the other hand, cannot.Zinc and other metals coat their gills so they can't breathe and quickly die, MacDonald said.It turns out that one of the Eagle River's cleanest sections runs along between the old mine site and the treatment plant, along a trestle and pipeline carrying Eagle Mine waste water to the treatment plant.The water is so clear that native Colorado brown trout can live in that stretch of river. The downside is that their main predator, cutthroat trout, are an invasive species and can live there, too. The cutthroats are pushing out the native species.Still, it's a better problem than the river used to have, MacDonald said."It's dramatically improved," MacDonald said.The EPA and the Colorado Department of Public Health and Environment began reviewing the progress of the cleanup every five years, beginning in 2000, in which the review determined that significant progress has been made in restoring the Eagle River. In 2005, the review showed the cleanup remedies were "continuing to be protective of human health and the environment."In 2008, however, at the third so-called five-year review, the remedies were determined to not be protective due to recent changes in water quality standards adopted by the Colorado Water Quality Control Commission. The review determined that further zinc reductions were necessary.The next five-year review is scheduled to be completed no later than Sept. 30, 2013."Crappucino"Don Houston helps run the treatment plant that cleans water from the mine. Houston cuts to the root of the issue - local mining."It makes sense that there are lots of mines here. There's a lot of metal here," Houston said.Then he held up one of six quart-sized Mason jars on a table in front of him. This one was filled with an orange-ish colored liquid, which was actually water that comes straight from the mine. He swirled it around in the jar and grinned at the name it has earned, "crappucino."The raw mine water runs four miles through a gravity-fed pipeline along a trestle on the valley floor. The old wooden pipe was lined with plastic a few years back to keep it from leaking.The water and metals are separated from each other through a series of filtration tanks. Polymers and other things are added and extracted to help the process, and about 350 gallons a minute are purified and put back into the Eagle River, Houston explained. Heavy metal heavenThe area is pockmarked with mines sunk during Colorado's gold and silver boom of the late 1800s. The railroad started rolling through Gilman and the mine area in 1882.The Mabel mine was a million dollar operation, back when gold was $36 an ounce, said David Hinrichs, with NewFields, the environmental consultant with CBS.So were the Percy, Ben Butler, Tip Top and Rocky Point mines. All were within a few hundred yards of one another.The Eagle Mine started as a gold and silver mine, as did most other mines around here. It grew into the largest underground zinc mine in the country.The main shaft descended 900 feet below the surface. You can still see it rise above the ghost town of Gilman.The miners went down, the ore and other material came out and everything was fine - for a while.The Eagle Mine is a fairly dangerous place, and they really don't want you poking around back there, Hinrichs said.He points to dozens of huge boulders that are perched to fall at any moment. The soil still contains arsenic, among other surprises."If it looks dangerous, it is," Hinrichs said.Staff Writer Randy Wyrick can be reached at 970-748-2935 or firstname.lastname@example.org.