A mining project in Santa Cruz County threatens the residential water supply

Recently, residents of Patagonia, a small mountain town in the southeastern part of Arizona, have been receiving troubling letters.

They’re from a mining company called South32, and they’re raising concerns about the impacts of industrial expansion on the region’s water supply.

Reporter Wyatt Myskow wrote about the letters and their implications for Inside Climate News.

Full conversation

SAM DINGMAN: Wyatt, good morning.

WYATT MYSKOW: Good morning. Thanks for having me.

DINGMAN: So for folks who haven't been to Patagonia, what's it like there? This is a beautiful place, right?

MYSKOW: It is a beautiful place. It's a charming mountain town located in the borderlands. Patagonia Mountains, they're one of Arizona's most famous sky islands. Which are a range of mountains, that connect the Rocky Mountains to the Sierra Madre Range in Mexico. And they're famous for essentially being islands of refuge for wildlife across the region to escape the extreme heat. And they're home to just a range of species that you don't typically find in the desert.

When I went down there last month, I met with a man named John Nordstrom who lives in Coronado National Forest. He was one of the residents who got one of these letters from South32. He lives ... deep in the forest. When I arrived, you know, there were wild turkeys roaming his yard, javelinas. He showed me pictures of black bears and cougars and coatimundi that roamed through his yard, But the landscape is changing, which is why people are so concerned.

Amber Victoria Singer/KJZZ

DINGMAN: Yes, and that brings us to these, these letters. So, so tell us what these letters say.

MYSKOW: Yeah, so South32, they have this project called the Hermosa Project. It is a silver, lead, zinc and manganese mining project that is being essentially fast tracked but under both the Trump and Biden administrations. And recently, the environmental impact statement came out from the U.S. Forest Service, putting essentially, you know, that this project will be approved soon. Here's the kind of final environmental impacts that will happen.

And one of the big ones is that there will be a essentially what we call a cone of depression. Which means the local aquifer will essentially drop. And that will potentially affect homeowners across the region. And in Arizona there's no rule of laws that stop a company from doing this. But getting ahead of the curve, South32 sent out letters to homeowners in this kind of depression to let them know your wells may be affected.

And if you sign this contract that will make us the sole arbiter of deciding what went wrong and how to fix it, we will fix your problem. Now, that is on the one hand good because at least they're taking initiative — because they don't have to legally. But on the other hand, residents are very concerned because you get a letter in the mail and suddenly you're being told you're well — mind you, these people are not on a city water line or anything like that. They have wells out there.

And if that well goes away, if they can't get their water, you know, what does that do to their home property values? What does that do to their ability to drink the water? Do they trust the company? Many of them don't. ... This project has been in the works for a long time. Folks are a little untrustworthy for many reasons. And so it's a big concern for a lot of folks.

DINGMAN: Well, and some of them are already starting to notice issues with their water supplies, correct?

MYSKOW: Yes, that's true. John Nordstrom, for example, the man I mentioned in the beginning, his water levels have dropped 87%. And he's had the company come monitor his wells for a few years now, and they share this data with him. He got this data, and he saw it dropped 87% over the past handful of months.

He also has a local creek in his backyard as well as a pond that, you know, before it was wet ... most of the time. And the pond was wet year round, that has gone dry. And then slightly more concerning, I think potentially, another homeowner I spoke to did not get this letter, but she has had a problem with what she calls an iron sludge.

In 2021 after the mine began dewatering the aquifer and began doing some mining activity — mind you, this is pre any approval to actually begin digging and extracting those minerals — she started getting this iron sludge. Essentially this, you know, metal-ly sludgy stuff appearing in her well, and she stopped drinking it. And there was high levels of lead, other things that were not good in there.

She wasn't sure what the problem was. Again, this is an area that has had a lot of mining in the past, what was going on, she wasn't sure. But in recent months, her lead levels have risen from 0.0007 mg per liter to 0.479 in recent months. That may be ... small numbers, but that's a huge increase in just a few months. And keep in mind the Environmental Protection Agency's maximum contaminants for lead in your water is zero. Any level of lead is not good in your water.

And so, her theory is, as well as hydrologists and something that the U.S. Forest Service also found in their environmental impact statement when they, you know, discussed potential problems the mine could cause to water, is that the water coming from the mine is clean, but they're dumping it into the local creek.

Oh, maybe I should explain something really quick. When we mine, we dig into the earth, and there's other things down there besides the minerals they want. One of those things is typically water, and you can't extract those minerals until that water is out of the way. So they do what they call dewatering, which is exactly what it sounds like. They take the water out of the aquifer, and they put it somewhere else. In this case, they are taking that water out, they are treating it to, you know, EPA standards, state standards, and then they're dumping it into a local creek.

But that creek contains minerals in it such as lead. And that lead, then the theory is is that lead is now making its way into her well because she lives right off the creek and now that there's all this water in there, it's activated all these contaminants that previously were just kind of staying stagnant.

And so that's a big concern for folks both in the town, both living on the outskirts in the forest everywhere all around. Is that not only are water levels dropping but also contaminants, maybe at least for one home, are going up. And what does that mean down the road?

DINGMAN: Right. Well, just about 30 seconds left here, Wyatt. I mean, you mentioned they're getting these contracts to sign. If folks don't sign the contracts, do they have any other options?

MYSKOW: That's the big question. And I spoke to a water expert at Arizona State University. And really because, you know, outside of the major cities for the most part in Arizona, there are no rules on groundwater. You can pump as much as you want if you cause a neighbor's well to go dry, that's legal. That's OK.

Now, you could be sued for that potentially. Would they go anywhere though, hard to say. Her recommendation was that people probably should sign these even though they're scary. Because ultimately it's the only choice you have.