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Pot: Not so green after all?

By Shannon Service

California’s marijuana industry is worth an estimated $14 billion. But large marijuana growing operations — most of which are illegal — are polluting local ecosystems on an industrial scale in rural counties and places as unlikely as state parks.

The cultural secrecy around the illegal product means diesel spills go unreported, spikes in electricity overlooked and gallons of toxic pesticides wash into rivers and creeks. And without tax revenue from marijuana, state agencies struggle to find funds for cleanup.

In this video, reporter Kate McLean investigates pot pollution in California.

Although some growing operations, or “grows,” are authorized for medical marijuana production under a 1996 state law, most are illegal. Drug cartels raise plants beneath bushy overgrowth in state parks right under the noses of law enforcement, and throughout the state, pot gardens are squirreled away inside trailers, closets, attics, basements and spare bedrooms.

Marijuana has sprung up in one-third of California’s state parks and 40 percent of national forests over the past decade, according to a Mother Jones article published last year. Farming pot on public land is more lucrative than smuggling it across an increasingly militarized Mexican border, they reported.

Much of marijuana’s environmental impact stems from the huge amount of light needed to grow plants indoors, where they can thrive year round hidden from law enforcement. Some growers power their giant “grow lights” with electricity from the grid. But those in more rural locations use large diesel generators for power, often shoddy and homemade, which are huge risks for fires and spills.

In Northern California’s Humboldt County, authorities estimate that over 1,000 gallons of diesel have spilled so far in just one stream, which like many others is the only water source for those who live downstream. Off the grid and out of cell range, many neighbors don’t have phones and receive word of water pollution late — if at all. Even with the inherent dangers, neighbors are reluctant to report the spills fearing blow back from nearby pot farmers who are also often friends.

On-grid grows carry another set of problems. Marijuana growers use an estimated 90 million kilowatt hours per year, “about 70 times the total output of all the solar panels in the county… enough to power 13,000 typical homes,” a recent Humboldt State University report found. The extra electricity pumps an estimated 40,000 metric tons of carbon dioxide into the atmosphere each year, as much as 7,000 cars — and that’s just in one county.

The ecological harms of marijuana reach well beyond the buzzing homes of Northern California. In state and national parks, growers clear native vegetation, use illegal pesticides and chemicals on the pot plants, divert precious water from streams and often kill bears and other animals that threaten their operation.

A recent clean up of a grow site just outside Yosemite National Park uncovered miles of irrigation piping that drew creek water to the marijuana plants. Bags of fertilizers and chemicals were found strewn around the growers’ campsite. But according to a park official at the scene, this site was relatively mild. Hundreds of similar scenes dot California’s parks and wild places — a relatively recent phenomenon that seems to grow with each passing year.

Detecting and cleaning up spills and illegal marijuana camps is complex. In addition to scarce funding, law enforcement officials face jurisdictional issues. The job is largely left to a handful of trail crews with huge swaths of ground to cover.

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