Randy Martin Interview
Randy Martin: Our bad air in Logan is almost exclusively a wintertime problem. And our bad air happens to be with the pollutant called PM2.5, which is all particles suspended in the air that are two and a half microns and smaller. One of the main reasons we have this problem is we are an enclosed valley. North, south, east, and west, we are surrounded by mountains. The valley floor is about 4,500 feet, the mountains go up to about almost 10,000 feet, so we're, we're a big bathtub.
And then in the winter time, we get snow cover on the ground and that enhances the formation of low level inversions. So we have a seal on our bathtub, and then whenever we get put into that bathtub, stays there until a storm comes by and clears it out. We have no single large point source, we can't point to any single industry and say clean up your act. What we have are a lot of small area sources in cars, mobile sources.
So, our cars and our area sources emit a fair quantity of what are called VOC's, volatile organic compounds. They also emit oxides of nitrogen, or NOC's. Those two species go through a series of chemical reactions. And then we also have in our atmosphere lots of ammonia, due to our very strong agricultural base here. So, you take the reactions of the NOC's and the VOC's, they ultimately for a compound called nitric acid, which is a gas phase. That combines with the ammonia in the air and forms ammonium nitrate, which is the main component of our PM2.5. It just is our blessing, if you will, that we have all the right components to form PM2.5 in our wintertime atmosphere. And it's such an enclosed valley that it can get to be very high levels.
Randy Martin: A lot of it is because there's no air moving in the valley, as I said. It just puts a lid on our valley so nothing can be mixed in or out. One of the unfortunate things, or if you're interested in studying it, the fortunate things is the formation of ammonium nitrate is actually favored, at low temperatures and high humidity's. And so, our winter time atmosphere is really ideal for the formation of PM2.5. Something that is in our benefit, however, is our indoor air. [When the PM2.5 comes indoors through your ventilation system, it heats up and then that disassociates, it goes back to the gas phase, so, our PM2.5, here in the valley, is much lower inside than it is outside.
]
Randy Martin: We kind of say shorthand, it's cows and cars in the valley, but that's not really totally correct. As I said, the ammonia, I think it's 85, 90 percent of it comes from the egg industry. It's a wide range of sources within the egg industry. And we know that our ammonia in the valley is actually rich by a factor of two to six. In other words, there's lots of excess ammonia.
So we have to look to the other side, the VOC and NOC's. The NOC's come from any combustion source. But, primarily, by far our largest source of NOC's in the valley are our mobile sources. Cars, trucks, trains, anything that moves that has an engine, it produces NOC's. And that's by far our largest source here. The VOC's are kind of split between our cars and then these other area sources. These are things like gas stations, dry cleaners, restaurants, cabinet makers, auto body paint shops. Anything that uses a solvent of any sort emits VOC's.
So, we've got this very diffuse sources all across the board, which is one of the problems in trying to clean it up a little bit. Everybody has to contribute because everybody's part of the problem.
Randy Martin: Well, the Wasatch Front also has a PM2.5 problem in the winter time. They don't have quite as strong of an ammonia source as we have up here, but the dominant species in their particle is still ammonium nitrate. Although they have some ammonium sulfate, and a little more elemental carbon and organic carbon that we have here in the Cache Valley. But it's just a much larger population base, and you have a lot more industries out there emitting pollutants into the atmosphere as well. So, it's just a much, much larger air shed to deal with. One of the fortunate things about the Wasatch Front is it's not as enclosed as the Cache Valley is. You've basically got all that area out to the north northwest of the Wasatch area where things can clear out and blow out a little bit. So that's why the air pollution season, which officially starts here at the first of November, and down in the Wasatch it goes to the end of February. Up here, it tends to hang on till about the middle of March.
Randy Martin: Air shed is just a geographical area that has a common atmosphere in it. So, an example down along the Wasatch Front is you have the Salt Lake, Weber, Davis air shed, and then you've got Utah County. So, you're sort of separated by that little mountain ridge right around Thanksgiving Point there that separates you into two air sheds that you can manage separately. Whereas up here in the Catch Valley, we're all one big air shed, but it extends up into Idaho. And so we share our air pollution, they share theirs with us. And we're one air shed, but we're two different states. And not only are we two different states, we're two different EPA regions. So there are some administration politics we have to deal with up here that you don't have to deal with down in the Wasatch Front.
Randy Martin: By definition, what is poor air quality? That's really a leading question because it depends on whether you're talking about legal definition or if you're talking about health effects. Legal definition, poor air quality is when a given pollutant exceeds what has been established as the National Ambient Air Quality Standards. For PM2.5, the standard is 35 micrograms per cubic meter averaged over a 24-hour period. There's also a long term annual average that's 15 micrograms per cubic meter over the whole year. That's considered when you get into bad air. There has been a lot of studies in the last decade or so that have shown that that 35 microgram level is not protective enough. And it's perhaps not even close. We should be protecting at a much lower level. So when you talk about what is bad air, what is good air, it's a fuzzy target depending on whether you're looking at when health effects can be perceived or what the legal definition is.
Randy Martin: Well, PM2.5, it enters in through your lungs so it's a respiratory issue, and lots of disease states have been associated with PM2.5. Dr. Arden Pope down at BYU has come up with many, many, very fascinating epidemiological studies linking PM to lung cancer, diabetes, bladder cancer. All manners of anything that is associated with the cardio-respiratory system. And there's a lot of cardio effects that are now being attributed to PM2.5 as well. The list is many pages long.
Randy Martin: Well, I moved into the valley in 2000 and started teaching here. And coincidentally, at about that same time, the state started measuring PM2.5 here in the valley. They were only doing it on an every three day basis because that's all that was required by law at the time. And it became very obvious in the wintertime, just that, those first, well actually 2001 and 2002, when we had complete years worth of data, that we had very high values in the wintertime. [They were high enough that they potentially exceeded the old PM2.5 standard, which was 65 micrograms per cubic meter. And in 2002, we actually recorded the highest value here in the Cache Valley that's ever been recorded in the state here was 137.5 micrograms per cubic meter over 24 hours.
And so that got a lot of people's attention. We knew we had a problem. We knew we were going to have to address it, so the air quality task force was formed, here in the Cache Valley, made up of scientists and politicians and public that were interested. And it was really trying to identify, trying to get an early jump on identifying what the problem was here in the Cache Valley and why we had this problem. So that just started a whole series of little studies trying to figure out, you know, what are the particles made up of, how often do we get inversions, how deep are the inversions, what are the sources of ammonia, are we ammonia rich, are we VOC limited. All those questions we tried to get a handle on an answer. Are our cars more polluting than cars elsewhere, we did, you know, on road vehicle studies. So we did a lot of work trying to identify what the problem was, why we had it here, and what could maybe be done about it.
Randy Martin: Well, the successes that came out of that I think we understand pretty well our problem here. To date, there haven't been any really programs implemented, I should say mandated. There has been a lot of suggested programs. There is one mandate program, the no-burn night. When we have bad air, you're not supposed to burn your wood stoves, and that is written into law. But only recently, and when we first developed, started developing the state implementation plan, were there things that were codified and are going to be mandated starting January 1 of this year, or of 2014 such as the vehicle inspection program, and control limits on some of the other diffuse area sources out here in the valley.
So, those first years were really just education years, and we did a lot of public outreach, trying to teach the community what the problem was and why we had it, what could maybe be done about it. Including a lot of suggested volunteer type programs like carpooling, limit your driving, those kind of things. Walk when you can. Some people, Dr. Ed Redd you've mentioned, he rides his bike every singleday of the year. It doesn't matter whether it's rain, snow or sunshine, he still rides his bike.
Randy Martin: Well, over the last three or four years, the air quality seemed to have stabilized a little bit, kind of just a little bit above what the standard is. It was averaging around 40 micrograms per cubic meter, on our average winter bad days. So, we're still above the standard. And so it wasn't getting much better beyond that. It certainly wasn't the concentration of the early 2000's. Until this last year, 2013. 2013 was much more inverted year, we had snow on the ground, we had stagnant periods. And so it ended up being a relatively bad year. I think it was fourth or fifth worst since we've been measuring here in the valley. So, it's hard to say if it's getting better.
Last year was a bad year. We do know that we've had what we call vehicle fleet turnover. We've got a few newer cars on the road than we had ten years ago. So, that by itself, is a plus, but we also know that people are driving more. The vehicle miles traveled increase quite a bit. The population has increased in the valley. It's increased 25,000 since I've been here.
So, the valley is growing, and that's kind of, I won't say equaling the new cars, but it's certainly impacting it in which way the balance is going, you know. Are we getting a net improvement or are we getting a net decrease, or increase in the number of emissions.
Randy Martin: Yeah, even with new cars on the road, if we have the area sources clean up, we're still going to have days with bad air. What our goal is, from a regulatory standpoint, is that our regulatory value, which is essentially our sixth highest value in any given year, that value needs to average below 35. So we could still have some high days, legally, that are over 35 but that, what's called the 98th percentile value needs to be below 35. And the best models that we have right now tell us that if we put these programs in place, we will get below that 35. So, yeah, I think once these programs are in place, we will see a decrease in the concentration and it should get below the standard but there will still be days when it's going to be high.
Now hopefully it's not going to be 137, maybe that high day is going to be 70. It's going to be some lower. That regular hurry value should, according to the models, be below the standard.
Randy Martin: Well, there is a lot of different air pollutants out there, PM2.5 being one, ozone being another. Ozone is generally a summertime problem. It takes sunlight to form ozone. And in the wintertime, we just have less sunlight. Now there are places around the country, like the Uinta Basin here in Utah, and the Pinedale area in Wyoming that have a winter time ozone problem due to some unique circumstance in meteorology and source strengths. But, ozone is generally a summertime problem.
Around here in Cache Valley, we have enough atmospheric ventilation that we don't get a lot of stagnant periods in the summertime, so the air is cleaner, it just blows out more. Their mixing depth is much, much deeper. And then we just don't have the source strength to allow that ozone to form too much. Although, even in Logan, we've bumped up close to the standard, the summertime standard. We haven't surpassed it, but we've bumped up close to it. And if the valley continues to grow, like it suggested it that it will, we could have summertime ozone problems.
But, the American Lung Association study, they look at those pollutants individually and say, okay, yes you're bad for ozone, yes you're bad for PM2.5, whatever the situation happens to be in the given locality. We happen to be bad, as we've talked about, for the 24 hour PM2.5 standard. It you look at the annual PM2.5 standard, we're actually sitting in pretty good shape because our summertime values are so low. But our wintertime values are pretty high. So, you have, depending on which air pollutant you have to talk about, that's how you look at that statistic. Each pollutant is bad in its own right, if it gets to a high enough level.
Randy Martin: I think as far as the PM2.5 in Logan, I'm not going to say the problem's solved, but I think we understand it. And now, it's up to the community to try to reduce the pollutant. And, like I said before, once we realize that we're all part of the problem, we all got to pitch in and make sure that we're driving our cleanest vehicles, and we're limiting our vehicle miles traveled. And it comes right down to it, that's what we need to do is we need to limit our vehicle miles traveled. Not just during the red days, but during the yellow days, when it's building up to the red days. And we just gotta become aware that in order to solve this problem we all gotta pitch in and work on the solution.