Arizona Geological Survey

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He recently briefed the Arizona Corporation Commission about earthquake hazards near the Palo Verde Nuclear Generating Station. Lee Allison, state geologist and director of the Arizona Geological Survey, talks about the state’s seismic monitoring network which is due to run out of funding this summer; earth fissures; and what may be a large deposit of a highly sought- after mineral near Holbrook.

Ted Simons Joining us now to talk about a variety of issues, including fissures, mineral deposit and what happens to all those rocks at the mining museum, is Lee Allison, the state geologist and director of the Arizona geological survey. Good to have you here. Thanks for being here.

Lee Allison: Thanks Ted.

Ted Simons: What happens to all those rocks?

Lee Allison: Some of it is going to go back to the people who donated it, loaned it, but the materials that belong to the museum, there's still a question long-term. So the survey has offered our assistance to the historical society, we've got the University of Arizona mineral museum, we're all working together to provide technical support and expertise as they pack things up and also if things are going to go out on loan or display, we're going to provide technical support to them.

Ted Simons: The idea of a mineral collection is one thing, but there are other things, there are journals, there are maps, there's research dating back over a hundred years. What happens to all that stuff?

Lee Allison: That's actually been transferred over to the geologist survey. In January we took over the department when they ran out of money, and we've kept the doors open for all their historical records and files. A lot of it is irreplaceable. One of a kind documents going back 150 years. So the legislature is just formally transferred the department and its assets, so come July 1st we will be operating those and making sure they're available.

Ted Simons: Historical society says we will include mining and mineral stories and history of that in the new Arizona experience. Can they do that? Is that viable?

Lee Allison: Wow. It's a big challenge to cover not only the history of Arizona, but the future of Arizona. And the five Cs and put all of that together in one building. And so I think it's pretty clear that they're not going to have anywhere near the space they had for mineral and mining displays. There are other mining museums around the state, there's a big mineral museum in Tucson, so we're all going to work together to make sure that the assets are preserved, they're in good homes, or if there's temporary storage, that things are taken care of until a longer term home is found.

Lee Allison: Alright very good. I want to get to other concerns, including seismic hazards near Palo Verde. We saw what happened in Japan. Everyone is obviously concerned about that. Talk to us about what you found out there, what you reported to the corporation commission.

Lee Allison: Well, a lot of people think Arizona doesn't have earthquakes. We do. We have not had a major damaging earthquake since territorial days. And so that's good news. But it also lulls us into a false sense of security to some extent. We've had a magnitude 7.5 earthquake just over the border in Sonora in 1887 that did a lot of damage across southern Arizona. Fortunately people had a lot of this information when Palo Verde was being built. So it's built in one of the most quiet areas in Arizona for earthquake activity. So that was intentional. So that's a good place to start. Also, when they designed it, it was intended to withstand a magnitude 8 earthquake at a distance of 100 kilometers or 172 miles. So that's what it's designed for. We don't see any earthquake capable faults in that region that would produce a magnitude 8.

Ted Simons: Wasn't a monitoring station out there vandalized not too long ago?

Lee Allison: Three years ago we set up the first statewide seismic monitoring that worked in the history of Arizona. And we had them scattered around the state. One of the stations we specifically located was west of Palo Verde to make sure we were collecting the kind of information that would give the plant operators the newest information about how the ground respond to earthquakes coming from California, say. Unfortunately, somebody stole all of the equipment. The power, the communications, the transmission, so it's gone. And we didn't have the money to replace it. So we focused more on keeping the rest of the network up and operating, and lost that station.

Ted Simons: Let's talk more about this network, the seismic monitoring network. I think we saw a map, if we could see that again, regarding -- it shows where seismic activity is around the state, it looks like a lot is clustered near Flagstaff. What's going on there?

Lee Allison: Well, if you think about the San Francisco volcanic field, we have 600 volcanos and the youngest one is less than a thousand years old. In geologic terms, that's yesterday. We have a very active potentially active volcanic region up there, and there's a lot of shifting and moving of the ground down at depth, and adjusting. So we're picking up a lot of that monitoring.

Ted Simons: OK.

Lee Allison: We're monitoring a lot of those small earthquakes.

Ted Simons: This monitoring effort, am I wrong, but I thought the funding was going to run out isn't it?

Lee Allison: We got federal funding to about it equipment and install it, and we're doing a three-year study with all three universities in the state to try to assess a modern interpretation of the seismic hazard across the state. That federal money runs out in June. So we're going through a process right now trying to see, can we redirect money from other projects or find them from other sources to keep the network running which is why we didn't replace the one station that was stolen, we wanted to keep it running as long as possible.

Ted Simons: You mentioned Palo Verde, correct me if I'm wrong but there is one Fisher out there, correct?

Lee Allison: Yes. There is an earth Fisher near fat silt. It's win their grounds, but it's no threat to the facility.

Ted Simons: Other fishers of note Arizona, I think we have a map on this one as well. There we go.

Lee Allison: That's the Maricopa and Pinal county area, and it shows the -- a couple of the does study areas as we call them. There are four counties with earth fissures due to subsidence, rapid withdrawal of the groundwater, the ground subsides and it cracks so we have these giant fissures form. We are now mapping them we're about 80% done making the first comprehensive map with high precision GPS instrumentation for the state. If you drive between Tucson and Phoenix down near eLoy, you go a little -- down the freeway, that's an earth fissures. It continues for eight miles and crosses the central Arizona project canal.

Ted Simons: But that canal is retrofitted for that isn't it?

Lee Allison: It's especially line and they come back and retroif it so it they make sure it doesn't open and drain the canal.

Ted Simons: Good for them! Real quickly, we just saw a hole in the ground, we have another picture of this -- didn't a horse get swallowed up?

Lee Allison: Yeah.

Ted Simons: This is in queen creek, correct?

Lee Allison: That's in the summer of 2007 during the monsoon season, and two years earlier a mile south of there, that same fissures opened up overnight and a homeowner's yard disappeared the same way this did. This one, the rain were so intense, it opened up so quickly, the horse was trapped and after about 32 hours of trying to rescue it, it died of exertion.

Ted Simons: And then -- this is rare but not all that rare, it?

Lee Allison: Not all that rare. In north Las Vegas they lost 243 homes to earth fissures. We've been lucky, we have not had that same devastation, but there are dozens and dozens of homes and apartments built on or next to earth fissures all over southern Arizona.

Ted Simons: All right. Before we let you go, potash is a big deal up -- I think near Holbrook. What is potash, and why is this such a major -- could be a major factor, I guess is a major factor, as far as mineral deposits in Arizona?

Lee Allison: Potash is actually a term that came from the 1500s where they would burn wood in these big pots and extract the potassium. So this ash came out of the pot and they would spread it on the fields, make soap, they would use 90 glass making. Today 95% of the potash developed around the world is used in fertilizer. And there's a worldwide shortage. The price went up almost 10 fold over the last three years, no new mines anywhere in the world in 30 years. And we found in the last three years, that about a quarter of all the potash in the United States lies out in the Holbrook basin just south of interstate 40.

Ted Simons: Let's put this on the desk. We just saw a shot of that. That is basically what's been excavated up?

Lee Allison: That's a core, so it's the drill bit went down 800 to 1,000 feet below the ground, cut through the potash, and it's like a dark salt. And it is. It's a potassium salt. And then you extract the potassium, and it's one of the three major elements in making fertilizer.

Ted Simons: You mentioned though that there was exploration underway, and a lot -- isn't a lot of that under a national park?

Lee Allison: The center part of the deposit lies directly under petrified forest national park. And it cannot be mined, it cannot be leased. But we've got a number of companies drilling out there right now, there's probably 40 core holes permitted or having just been drilled and a major exploration effort out there. This could be a billion dollar investment to mine the potash, but it would be the first new mine in the world in 30 years, and the -- our estimate is there's up to 2.25 billion tons of potash. And the price spiked at about a thousand dollars a ton during the run-up of -- it's pulled back during the recession, but it's run ball game $400 a ton. So we're talking, there may be hundreds of billions of dollars worth of potash that could be mined out there in that region.

Ted Simons: Thank you so much for joining us.

Lee Allison: My pleasure.

Lee Allison:state geologist and director of the Arizona Geological Survey;

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