Marijuana gardens in the Sierra National Forest

FRESNO, Calif.

Action News Reporter Corin Hoggard hiked into the high sierra for a rare look at what's happening on lands that should be protected, and the group trying to stop a big pocket of pollution.

An amazing view greets visitors standing 7,000 feet above sea level in the Sierra National Forest. Redwoods and Manzanita trees sandwich the Turtle Creek, and the pristine landscape is nearly untouched.

Action News was granted access to the remote location where only a few people have ever hiked, a spot where the view has been spoiled. This waterfall now leads straight into a pit of trash, the mark of a full-scale marijuana growing operation.

John Brinley with the U.S. Forest Service said, "Maybe 200 feet, 250 feet that way is a grow site."

Forest service agents are certain Mexican drug cartels are responsible for hundreds of the grow sites. The cartels are sending illegal immigrants into the forest, armed with guns.

Kevin Mayer with the U.S. Forest Service said, "They're guarding their crops. At certain times of the year it's more dangerous than others.

Growers also pose a danger even after they're gone because of what they leave behind. Even in a grow site that's been dormant for a couple of years, you can still see some of the tools of the trade, an irrigation line that waters the plants and some leftover fertilizer that helps the marijuana grow.

The fertilizers and pesticides may boost the marijuana harvest, but agents say the toxic chemicals kill wildlife and leach into the waterways that supply drinking water to Fresno and much of the Valley. And the growers spread the contamination across a large area.

"Now what they're doing to i think avoid detection, is you'll see a lot of these sites, so it might be like my hand," said Warren Sargent. "There's a site here and then each one of my fingertips would be another satellite site. So it takes a while once we get in here to actually follow all the trails out to see what might be here."

Federal agents could only clean about ten grow sites every year and they were losing ground. The High Sierra Volunteer Trail Crew drastically changed the situation when the group of nature lovers joined forced six years ago.

The trail crew has removed about 650 miles of irrigation drip line, 325 thousand pounds of trash, and 54 thousand pounds of fertilizer. The forest service credits the crew with erasing much of the environmental damage done by drug cartels at more than 300 grow sites.

Mayer said, "We have literally less than 25 still on the books that we know of, so that's really a tremendous accomplishment."

But for volunteers, the real reward is the view, and knowing it'll be this spectacular as long as they have anything to do with it.

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