What Lead us to This?
By TJ Ehlers
Have you ever noticed that big bucket of lead sitting around in the parking lot? Neither have a lot of students, but it’s been slowly floating around the campus since late last year. This bucket is fairly small, but moving it is a herculean task. It has a metal anchor jutting out from the center of it, and is covered in dents and scrapes from curious students wondering just how soft lead is.
The bucket weighs around 400 pounds, give or take about 10 pounds. That’s impressive, considering it could easily fit in a backpack. The density of lead is 11.34 grams/cm^3. To put that into perspective, aluminum’s density is 2.7 g/cm^3, and steel’s is 8.05g/cm^3. Lead isn’t the densest element though, with uranium being 19.1g/cm^3, and the champion being osmium, at 22.59g/cm^3.
The lead bucket was originally used in the 2015 trebuchet project, conducted by the Class of 2016. It acted as a counterweight in a trebuchet, where it provided potential energy to launch a pumpkin. The group that it originated from remains a mystery, but calculations can be done to see what the bucket could have accomplished. As taught in Brian’s class, potential energy is equal to the mass in kilograms, times the gravity exerted on it, times the object’s height. This means that a 400 pound bucket of lead hoisted to ten feet has a possible 17,738 joules of potential energy. Finding the maximum efficiency of a trebuchet was a bit trickier, but enough research revealed usable data. The American Society of Mechanical Engineers published a paper on just this, and stated: “The efficiency of the trebuchet increases by the addition of the sling (of this particular length) from 59% (for the previous example) up to 81%.”
It’s possible to work backwards from the results found at the exhibition. The best percentage to use is about 25%. Sadly, the trebuchets were far less efficient than originally thought. This means that 4434 joules of force are being exerted on the twenty pound pumpkin. Plugging the known values in, it can be calculated that a twenty pound pumpkin will be launched at 31 meters per second, or 69 miles per hour upon initial launch. Now that’s fast.
Despite the physics aspect of the lead, it’s impossible to bring up without also mentioning lead posioning. Lead poisoning’s effects generally include neurological symptoms, the most notable being convulsions, reduced IQ, and aggressive moods. The lesser symptoms include hyperactivity, nausea and vomiting, and there’s even a possibility for memory loss. While these symptoms all only occur when high levels of lead are in the body, the dangerous amount is considered to be 5 micrograms per deciliter of blood in children. The CDC says that some of these symptoms have been observed with even lower levels of lead in the blood, and that,in reality, no level of lead in the blood is safe.
Additionally, the Colorado Department of Public Health and Environment states that “Wastes with 5.0 parts per million (ppm) or greater lead content by [Toxicity Characteristic Leaching Procedure] exhibit the toxicity characteristic for lead and must be managed as hazardous waste.” It’s safe to say the lead bucket far exceeds that, by a few orders of magnitude. So, what should the school do about this? To contact an authority on the issue,Sean Woytek, Head of School was the person to talk to.
While the discussion was brief, it did bring to light a couple things. When the issue was brought up to Sean, he agreed to talk about it a bit. The biggest thing to take away from the discussion was that it wasn’t on the top of his list, but something was going to be done about it. First and foremost, Sean suggested that the school call Dave Heerschap, as he will build more trebuchets, and may want to use the lead for future classes and their projects. This will determine the decision to either remove the lead, or store it. The hardest part of removal would be loading the bucket into a car, but it would be possible to simply bring it to a foundry or scrap metal recycling center for disposal. Similarly, the school could also wait for the next hazardous waste fair, and dispose of it there. Libby Cowles, Assistant Head of School, has also expressed that she advocates for disposing of it. Removing it is important because Animas can likely face legal action if it has something classified as hazardous waste lying around its campus. The lead may not be a danger to students, but one to the school.
As another important note, if we’re going to talk about disposal and the environmental hazards of the lead, it’s worth noting the sheets of lead that were also left outside, behind the scrap wood. There are supposedly about 600 pounds of lead sheets here, and these are loose, not contained in a bucket. Although lead is corrosion-resistant, it doesn’t help that this scrap has been where it is for the better part of the year. This means it likely is leaching into the ground. An article published by Science Daily included an interview with a U.S. Forest Service employee that worked in and around areas containing large amounts of lead bullets and shot left on the ground. The employee expressed “we learned that [lead] is absorbed in the top few inches of soil”. The article concluded that, while not an immediate issue, lead in the ground increases risk of water contamination, and is, in itself, soil contamination. Even though Animas isn’t farming anything in that particular spot, or getting their drinking water from it, it’s important to advocate for the removal of lead from all outdoor, open places.
On the other hand, storing the lead somewhere on campus would present a couple issues, the first and foremost being where specifically it would be stored. Woytek stated that it might be a good idea to store the lead with Steve Smith in the chemistry department. However, after discussing the idea with Smith, he expressed that, at least in his classroom, he really doesn’t have any place to store it. Steve toyed with the idea of keeping it, and agreed that if it was to be kept around campus, it should at least be some place out of the weather, not just sitting around outside.
The lead bucket is a great example of something small in which mountains of data can be discovered. It has history, physics, and local school politics all playing into it, not to mention a healthy amount of science. When planning to write this article, I didn’t think it would be as lengthy and in-depth as it was, but when I started research, one subject just… lead to another.
By TJ Ehlers
Have you ever noticed that big bucket of lead sitting around in the parking lot? Neither have a lot of students, but it’s been slowly floating around the campus since late last year. This bucket is fairly small, but moving it is a herculean task. It has a metal anchor jutting out from the center of it, and is covered in dents and scrapes from curious students wondering just how soft lead is.
The bucket weighs around 400 pounds, give or take about 10 pounds. That’s impressive, considering it could easily fit in a backpack. The density of lead is 11.34 grams/cm^3. To put that into perspective, aluminum’s density is 2.7 g/cm^3, and steel’s is 8.05g/cm^3. Lead isn’t the densest element though, with uranium being 19.1g/cm^3, and the champion being osmium, at 22.59g/cm^3.
The lead bucket was originally used in the 2015 trebuchet project, conducted by the Class of 2016. It acted as a counterweight in a trebuchet, where it provided potential energy to launch a pumpkin. The group that it originated from remains a mystery, but calculations can be done to see what the bucket could have accomplished. As taught in Brian’s class, potential energy is equal to the mass in kilograms, times the gravity exerted on it, times the object’s height. This means that a 400 pound bucket of lead hoisted to ten feet has a possible 17,738 joules of potential energy. Finding the maximum efficiency of a trebuchet was a bit trickier, but enough research revealed usable data. The American Society of Mechanical Engineers published a paper on just this, and stated: “The efficiency of the trebuchet increases by the addition of the sling (of this particular length) from 59% (for the previous example) up to 81%.”
It’s possible to work backwards from the results found at the exhibition. The best percentage to use is about 25%. Sadly, the trebuchets were far less efficient than originally thought. This means that 4434 joules of force are being exerted on the twenty pound pumpkin. Plugging the known values in, it can be calculated that a twenty pound pumpkin will be launched at 31 meters per second, or 69 miles per hour upon initial launch. Now that’s fast.
Despite the physics aspect of the lead, it’s impossible to bring up without also mentioning lead posioning. Lead poisoning’s effects generally include neurological symptoms, the most notable being convulsions, reduced IQ, and aggressive moods. The lesser symptoms include hyperactivity, nausea and vomiting, and there’s even a possibility for memory loss. While these symptoms all only occur when high levels of lead are in the body, the dangerous amount is considered to be 5 micrograms per deciliter of blood in children. The CDC says that some of these symptoms have been observed with even lower levels of lead in the blood, and that,in reality, no level of lead in the blood is safe.
Additionally, the Colorado Department of Public Health and Environment states that “Wastes with 5.0 parts per million (ppm) or greater lead content by [Toxicity Characteristic Leaching Procedure] exhibit the toxicity characteristic for lead and must be managed as hazardous waste.” It’s safe to say the lead bucket far exceeds that, by a few orders of magnitude. So, what should the school do about this? To contact an authority on the issue,Sean Woytek, Head of School was the person to talk to.
While the discussion was brief, it did bring to light a couple things. When the issue was brought up to Sean, he agreed to talk about it a bit. The biggest thing to take away from the discussion was that it wasn’t on the top of his list, but something was going to be done about it. First and foremost, Sean suggested that the school call Dave Heerschap, as he will build more trebuchets, and may want to use the lead for future classes and their projects. This will determine the decision to either remove the lead, or store it. The hardest part of removal would be loading the bucket into a car, but it would be possible to simply bring it to a foundry or scrap metal recycling center for disposal. Similarly, the school could also wait for the next hazardous waste fair, and dispose of it there. Libby Cowles, Assistant Head of School, has also expressed that she advocates for disposing of it. Removing it is important because Animas can likely face legal action if it has something classified as hazardous waste lying around its campus. The lead may not be a danger to students, but one to the school.
As another important note, if we’re going to talk about disposal and the environmental hazards of the lead, it’s worth noting the sheets of lead that were also left outside, behind the scrap wood. There are supposedly about 600 pounds of lead sheets here, and these are loose, not contained in a bucket. Although lead is corrosion-resistant, it doesn’t help that this scrap has been where it is for the better part of the year. This means it likely is leaching into the ground. An article published by Science Daily included an interview with a U.S. Forest Service employee that worked in and around areas containing large amounts of lead bullets and shot left on the ground. The employee expressed “we learned that [lead] is absorbed in the top few inches of soil”. The article concluded that, while not an immediate issue, lead in the ground increases risk of water contamination, and is, in itself, soil contamination. Even though Animas isn’t farming anything in that particular spot, or getting their drinking water from it, it’s important to advocate for the removal of lead from all outdoor, open places.
On the other hand, storing the lead somewhere on campus would present a couple issues, the first and foremost being where specifically it would be stored. Woytek stated that it might be a good idea to store the lead with Steve Smith in the chemistry department. However, after discussing the idea with Smith, he expressed that, at least in his classroom, he really doesn’t have any place to store it. Steve toyed with the idea of keeping it, and agreed that if it was to be kept around campus, it should at least be some place out of the weather, not just sitting around outside.
The lead bucket is a great example of something small in which mountains of data can be discovered. It has history, physics, and local school politics all playing into it, not to mention a healthy amount of science. When planning to write this article, I didn’t think it would be as lengthy and in-depth as it was, but when I started research, one subject just… lead to another.