No Series: Galeet Cohen Teaches Environmental Science

Galeet Cohen Teaches Environmental Science

Lesson Objective: Simulate a search for patterns in groundwater contamination
Grades 9 -12 / Science / Groundwater
27 MIN


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Discussion and Supporting Materials

Thought starters

  1. Why is it important for the class to identify important information and plan prior to beginning the simulation?
  2. How does the real world connection motivate student learning and engagement?
  3. In what ways are students required to justify their analysis?


  • Private message to Marlon Wood

Freshmen "Plume of Axe"  :D  :D  :D

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  • Private message to Ben Shapiro

Love the tatoo, It's refreshing to see a teacher being able to expose a part of themselves and be true while also being a a respected educator.

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  • Private message to Carolyn Thomas
This was a very interesting lesson! Great questioning and student discussion
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  • Private message to Robert Townsend
This is an excellent lesson. Do you have a lesson plan, worksheets and resource information for it?
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  • Private message to Dana Straw
Awesome lesson. Do you have any resources to share?
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  • Arts Engine, Inc.
    Teaching Channel: WIAL 2

    GC Class

    [text] Galeet Cohen Teaches Environmental Science
    00:02:14 GALEET:

    Arts Engine, Inc.
    Teaching Channel: WIAL 2

    GC Class

    [text] Galeet Cohen Teaches Environmental Science
    00:02:14 GALEET: My name is Galeet Cohen. I work at Central High School in Philly. I teach AP and regular Environmental Science to 11th and 12th graders. The objective was for them to apply what they know about geology and groundwater to testing in this particular case study we’ve been looking at where there’s contamination in this place called Woburn [sp?]. I was trying to get them to think not just about gathering data, but gathering data in the real world where you have to make tradeoffs between what you can afford and certain limitations. So I wanted them to think about what type of data they could collect in a constrained situation and then I wanted them to think about different spatial and temporal factors that could affect the data that they’re collecting, and I wanted them to see the limitations of what they could get with a smaller sample size and then what happened when they looked at the whole class’s data.
    00:03:01 VOICEOVER: Prior to this class, the students have read the book A Civil Action, a non-fiction account of a water contamination case in Massachusetts in the 1980’s. Galeet has used the book to design today’s lab.
    GALEET: So what is another difference between civil and criminal cases? I can’t –
    STUDENT: A civil case is more of a settlement. A criminal case, uh, in a criminal case there’s a government – is the – prosecutor – I’m not sure.
    GALEET: Right, and in civil cases who tends to be the plaintiff? Not the government –
    STUDENTS: [unintelligible]
    00:03:42 GALEET: Right, or a company, or a person, or a group of persons together that have been wronged, right? And in a criminal case the law has been broken. So it’s the government that is seeking retribution for that, and in civil cases people have been damaged in some way – financially, some other way – and are seeking some sort of reparation for that, right? Ok, so you need different types of evidence, or different amounts of evidence, for each one, and I know this much about it [indicating a very small amount with her fingers] according to Mr. [unintelligible name]. So Bobby, what’s your guess?
    BOBBY: A criminal requires more ‘cause the total is “beyond a reasonable doubt”. And civil is “preponderance of evidence”.
    00:04:16 GALEET: You are awesome. Those are the exact words. How do you know that?
    BOBBY: Um, I took constitutional law sophomore year.
    GALEET: That would do it. Ok, so like Bobby just said, in a civil case you need a preponderance of evidence, right? So that just means that here’s evidence [arms outstretched as if she were a scale], and here’s a preponderance of evidence [tips to one side], you just need to like tip the scale a little bit in one direction. And in a criminal case, what did you say it was, Bobby?
    BOBBY: Beyond a reasonable doubt.
    00:04:45 GALEET: Right, beyond a reasonable doubt, which is much stronger language, right? You need this much evidence [tips much further to one side]. So the reason I want to talk about this today is that you guys are going to be looking at evidence so, um, from what you’ve read in the book – I have no idea what I did with, there it is – um, what were some of the types of evidence that Schlichtmann’s law firm collected when they were putting together the case? So what kind of evidence would help prove that the contamination came from somewhere and that it caused this leukemia cluster? Yeah [calling on student to answer question].
    STUDENT: Didn’t they take samples of the ground water underneath the actual land site and then the local – like all the estuaries.
    00:05:28 GALEET: Right, well, not so much estuaries ‘cause that means that it’s salt water. But groundwater, aquifer, right, is what you’re thinking? Yeah, so why would they do that? Why would you need to sample different spots, uh, different wells to look at the groundwater? What are they trying to prove? Yeah, Megan [calling on her].
    MEGAN: See if there’s a point source.
    GALEET: Right, and how would you know if there’s a point source instead of many non-point sources? Maybe it just rains TCE in Woburn; maybe that’s normal. Yeah, Joe [calling on him].
    JOE: As it clusters closer to a certain area, then you can suspect that there’s evidence that it’s coming from a certain point.
    00:06:07 GALEET: Right, so what you have here are wells, right? Or you don’t know that yet, but really what you have here are wells, ok? [motioning toward table in middle of class with miniature landscape] They’re enormous wells and they’re coming out of the ground. So this is an aerial map, and if you guys happen to have A Civil Action on you, you can look at the map that’s in the front, but I’ll project a map in a second anyway. Ok, but here’s some things you’re going to be interested in ‘cause the point of this lab is for you to test a bunch of wells. You are going to be a law firm, and you have a budget, and you can do some well testing to build your case, but you can’t go over budget. So you have to be very, very careful about which wells you want to test. So here’s some stuff you should know. Um, I think that this is north. And the most important things are the W.R. Grace is here. Right, so that was the company that Cheeseman is representing. The tanneries are over here; the tanneries are by the river. And the river runs through this area here, which you’ll see when you come up; it’s sort of like this wooded area. And if you do remember in the first part of the film, uh, John Travolta, i.e. Schlichtmann, goes over that bridge where he gets stopped twice, right? And so you know that there’s a river there; that’s the Aberjona River. And then – what else happened? Um, then when he has his revelation, remember he walks down to the river, sort of looks like a creek at that point, and it’s slightly wooded, right? So when you come here you’re going to see that this area is not developed; it’s got a bunch of trees and it’s riparian, whatever.
    00:07:33 Ok, so the other thing you might care about is that the cancer clusters – the leukemia, the alleged leukemia cluster – is here. There’s all these wells that actually got tested, and there’s data available online for them, so I sort of hijacked an existing kit lab and I labeled them with well numbers that correspond to where the real TCE was found, and you guys are going to have to decide which wells to test because you have $30,000 to test with. That sounds like a lot of money, but guess how much it costs to test one well?
    STUDENTS: [unintelligible]
    00:08:07 GALEET: No, it’s $3,000. [unintelligible speech of students] OK, oh – no problem then. So you can test ten wells then, right? Ok, I want to read you a little clip from the book that sort of will get you in the mood. Not that mood. So, alright, um, the well know as well G, which is one of these wells here, and I’m not telling you which one, uh, “has been sunk in the marshland on the east bank of the Aberjona River half a mile north of the Pine Street neighborhood. The well penetrated an ancient valley that had been formed 12,000 years ago.” What do you think was happening in Massachusetts 12,000 years ago?
    STUDENT: Glaciers.
    GALEET: Oh, what? Huh? Glaciers, right, it was an ice age. So they were part of the formation of the valley, sort of like carving out that area. Ok, and then, check this out: the valley filled with mostly gravel – right, remember gravel? [holding up container of gravel], and then some sand [holding up container of sand] – and then what happened to the glaciers?
    STUDENT: They receded.
    GALEET: They receded, which ultimately means they melted, right? And so what do you think happened to all that water?
    STUDENTS: [untintelligible]
    GALEET: Yeah, but why is it so significant that it was, um, like gravel and sand that filled in the valley?
    STUDENT: ‘Cause it can probably move through those.
    GALEET: Right, ‘cause you remember, um, here’s the gravel, right, oh I could do this in a more exciting way [filling up container with water]. Alright, that’s good. Ok, so when you pour the water onto the gravel, what do you expect to happen?
    STUDENTS: [untintelligible]
    GALEET: Right, really fast. Do you see how fast that is? Ok, and notice I didn’t say that the, um, the valley filled with tons of clay, because if it filled with tons of clay would you have an aquifer?
    GALEET: No, because like when the glaciers melted – imagine this is a giant ice cube [holding up container of water] – ok, then what happens? [pouring water into container of sediment] Oh, bad job. [students laughing]. Look at this side. What happens?
    STUDENT: It just stays at the top.
    GALEET: Right. Do you remember why, though?
    STUDENTS: [untintelligible]
    GALEET: Wait, Tang Tang.
    TANG TANG: The pore size is too small so it goes out slow.
    GALEET: Right, so the pore size is so small that the water doesn’t really percolate. So the cool thing about Woburn is that there is this huge aquifer under it so there’s places for the water to go, but that also means that if TCE gets into it, it can spread throughout the aquifer according to what the sediment is, right?
    00:10:32 So I want you to think about if you just have this aerial map – I mean, they found, remember we read that paper they found Osama bin Laden basically, or that geography group, just by looking at aerial maps, so you can actually use aerial maps for quite a bit of information. So think about if you just have that map to go on, right, how can you figure out which wells to choose? And if you could magically get three more pieces of information out of me, which you’re definitely not getting from me, what would they be, ok?
    00:11:01 STUDENT: You know the distance from the suspected point sources, like where you think it would be coming from.
    GALEET: Ok, yeah. Distance from suspected point sources – [writing on the chalkboard] that is my phone [phone ringing; grabbing phone to turn it off]. Jeez [everyone laughing]. Busted. Ok, what else could you get from the map? Yeah, Tang Tang.
    TANG TANG: I think that will affect the pore system like up the river and down the river.
    00:11:35 GALEET: Oh, ok. So flow of the river upstream and downstream. Sure [writing on chalkboard]. Ok, somebody else – why would you care about where downstream is? Yeah, Mamade [sp?].
    MAMADE: If it’s downstream, that’s where all the water’s coming. The pace of the water coming downstream is better than it going upstream, which means it would spread faster –
    00:11:59 GALEET: And get diluted faster, too, right? Ok. So I’m waiting for one more that’s really important. So think about rivers; what do you know – must, not must, it’s probably true about this area right here [pointing to aerial map projection] compared to this area here.
    STUDENTS: [unintelligible]
    GALEET: Oh, say more.
    STUDENT: The river that is, like the change in elevation –
    GALEET: Yeah, you know something about topography, right, because why is the river located here [pointing to projection] and not here? There’s a reason for that.
    STUDENTS: [unintelligible]
    GALEET: ‘Cause it’s lower elevation and water cycle, basic water cycle, right, water flows down so you can infer from elevation stuff [writing on chalkboard]. Ok, so there you have information. Use it, don’t use it. Um, if you could know anything else about these particular wells, what would you want to know about them? Yeah, Jeff.
    00:12:46 JEFF: Concentration of specific carcinogens.
    GALEET: But that’s what you’re testing. [students laughing] You do get to know that; that’s the one thing you get to test for. But if you could know something else – if like the data fairy could visit you and, you know, dump data on you – what would you want to know? Ok, Gabe.
    GABE: Does the map show proximity to all the leukemia cases?
    GALEET: Oh, interesting. No, all it shows you is that they all happen here, but you would want to know about specific leukemia cases?
    GABE: Yeah, ‘cause I’d want to see if the wells are the same next to the houses and at houses where there weren’t –
    00:13:22 GALEET: Yeah, that makes a lot of sense. Ok, Bobby what else? Oh, and then Jess.
    STUDENT: How long have the wells been there? Like, were they were at the same time as the –
    GALEET: That’s so smart. So all the map tells you is space, right? It tells you nothing about time, right? And what – I think it was somebody in this group yesterday who said that a leukemia cluster is a series of cancer cases that are in the same area, but also have to be – importantly – at the same time. So, right, you would want to know when the wells were drilled and when the wells were pumping because when a well is pumping, it’s actually drawing water from the aquifer, and that’s going to change the rate of slow everywhere else, right? So temporal information [writing on chalkboard] about the wells. Ok, one more thing. Oh, Jasmine.
    JASMINE: That was my answer.
    00:14:12 GALEET: Oh, well that was a great answer. I’m surprised there’s one thing you’re not saying. [motioning to student to answer]
    STUDENT: Which aquifer the well is coming from?
    GALEET: Oh, so it’s possible there’s multiple aquifers in the area? Ok, so –
    STUDENT: Like if G&H are getting their water from the evil little aquifer –
    GALEET: Evil aquifer, ‘cause there’s good and evil aquifers.
    STUDENT: There are!
    GALEET: It’s like a moral issue. Ok, so I’m gonna change your answer a little bit and just write that you want to know more about the hydrology of the area. So where’s the bedrock, where’s the gravel exactly, is the layer of gravel the same everywhere? Probably not, right? So – hydrology [writing on chalkboard]. Ok, those are all good thoughts. Ok, so what are you actually gonna do? Do you guys see the green baskets that are mysteriously under the table? Ok, so those contain things that you will need. And the things that – you don’t need very much, actually. So you’re gonna have a template, ok? [holding up well plate] So it’s actually called a well plate. Get it, wells? Anyway, um, so you can only choose ten and the way that you test a well is that you come up and you only get one at a time ‘cause they’re communal wells and you need to make sure that you put them back roughly where you got them. You’ll see that there’s the masking tape and it corresponds to the actual well that exists in Woburn, ok? So the way you test it is you put maybe like four or five drops in a certain well plate. And you just do one at a time because there’s the data table for you on the lab. And then – yes, there’s no TCE in this lab. You’re not getting cancer, just so you know. It’s low stakes.
    STUDENT: But I really like carcinogens. [laughing]
    00:15:52 GALEET: You get them everywhere; you don’t need to get them here. So, um, what you’re actually testing for is PH; that’s like the dirty secret. You can pretend it’s TCE; that’s much more exciting. Um, but you’re going to use a universal indicator, which is a PH indicator, and when you drop it on a given well it magically changes color. [demonstrates this] Oh, right, so this one – oh, I don’t know, two or three drops – until is changes color, right, the trick is to put in on a white background so you get a real reading of the color. And the colors are associated with concentrations of TCE. So Red it actually really good news; it means that it was barely detected. And then as you get into yellow, green and blue, it becomes more and more concentrated. So the EPA’s limit for TCE was five parts per billion, is determined to be unsafe according to the Clean Water Act. So the highest concentration that you’ll see in this lab is actually over thirty parts per million. So, it’s crazy. Anyway –
    STUDENT: Per million or per billion?
    GALEET: Sorry, per billion. Oh, order of magnitude. Big difference. Ok, um, the other thing that you have are these [holding up tool]; we probably won’t get to any sort of graphing, but we’ll see. Alright, so once you have your data, you write it on your data sheet and then you come up here one at a time, like as you get your data in your group, and you’re gonna put your data on the map. So, for example, the one that I just tested was OL1 and it was red, which means not detectable. So I’m gonna come pick red – if you don’t see the color you want, just double-click and then, you know, you can just pick the color that you want that’s – [students laughing] what? Uh, and then what I want you to do is either write the number, like 1 in red, or you can circle it, just so like we have a pictorial image of it and then we can figure out where the plume is flowing as a class, as group data. Do you have any questions? Good, then work with whoever you want. Only one paper per group, the papers are up there, grab a basket –
    STUDENT: How many people?
    GALEET: Four people per group.

    [students up moving around, working on the project]
    00:17:58 STUDENT: Where are the houses that we keep again?
    GALEET: They are here [unintelligible words].
    STUDENT: Ok, and where’s the factory?
    GALEET: Grace tanneries.
    STUDENT: How many of those do we need?
    GALEET: You can have ten.
    STUDENT: [unintelligible]
    GALEET: Yeah, but pick them one at a time.
    STUDENT: [unintelligible]
    GALEET: So, once you have one – have you ever played this game called minesweeper? Right, so if you have one, you have information about what might be around it. So, if there’s nothing over here, then you might not want to bother. But if this seems to be a point source, then you might want to move in some direction from there. So don’t just randomly take ten.

    [moving around room to another group]
    Do you guys have data yet? So go put some of it up before it gets too crowded at the whiteboard.
    STUDENT: How do I pick a new color? [at whiteboard]
    GALEET: Double-click on the color. It’s all in the wrist. Oh, so this was not very contaminated at all. Bottom right [indicating where the well is located]. Yeah, so isn’t that interesting that you can have like a non-contaminated one so close to a pretty contaminated one?

    [moving to another group]
    00:19:08 GALEET: You struck out three times. But that’s not a bad thing.
    STUDENT: How did we strike out three times?
    GALEET: It just means that you didn’t find TCE. So, if you were the lawyer, you would be upset.
    STUDENT: But we found it –
    GALEET: You did?
    STUDENT: On our first try.
    GALEET: So what direction are you going from this well?
    STUDENT: Ok, well this is the well located right around –
    OTHER STUDENT: No, this isn’t Grace –
    GALEET: Is it the tannery?
    STUDENT: This is Grace. No, this is the actual cancer cluster. So, right about the cancer cluster –
    GALEET: Oh, well, that was a smart place to start.
    STUDENT: Um, near the tannery. And this one’s Grace, this one’s the middle, and this is north, right? You said the top was north?
    GALEET: Yeah.
    STUDENT: This is north of the place. And then this is actually south of the – well, the most couther tip, which is, uh, right below the place. So this one is actually right here.
    GALEET: Oh, ok. So it sounds like you’re sort of scattering. If you found that there is TCE in the cancer cluster, which is over here [pointing to aerial map], right? And you don’t think that it’s coming from Grace, it seems, right? Where else can you concentrate your wells now?
    STUDENT: Well, uh –
    GALEET: ‘Cause you have five more to go, right?
    STUDENT: I guess near the tannery.
    GALEET: It’s a good start. Yeah, so you could see if it’s coming this way; you could kid of create a line. Alright.
    STUDENT: But this isn’t the map that’s on the, uh –
    GALEET: It’s roughly the map. So the cancer cluster – so the map that I gave you doesn’t include most of this; it stops kind of here. But everything else is here; Grace is here, right? It’s on there. The tanneries are here. The cancer cluster is here.
    STUDENT: Ok.
    GALEET: It’s roughly the same.

    [moving around room to another group]
    00:20:41 GALEET: Alright, you guys, what’s up?
    STUDENT: Waiting for our wells.
    GALEET: Who got them?
    STUDENT: [unintelligible]
    GALEET: Do you have any data?
    STUDENT: Nope, not yet.
    GALEET: Wait, what?
    STUDENT: They’re doing the wells and we wanted to choose all the wells first and then come back and do all of them at the same time.
    GALEET: How are they keeping track of which well is which?
    STUDENT: Tang Tang has it on her notebook.
    GALEET: Ok.

    [moving around room to another group]
    00:21:05 GALEET: How about you, Dina? [sp?
    STUDENT: I’m writing it down.
    GALEET: How’s it going? What did you find?
    DINA: Good, we found one that was blue-green. So we’re like testing wells closer to the river, but next to the – it was next to the –
    STUDENT: This one’s green so it definitely shows a point source at the Grace place.
    GALEET: So, bur now here comes the difficult part, right? You might have a point source, but can you link that to the leukemia cluster? So did the point source actually cause the leukemia or is it just dumping?
    DINA: We checked all the way downstream where the answer was no so I guess I feel like we have to check on the other side.
    GALEET: Right, right. Good plan.
    STUDENT: Do we get another well?

    [speaking to the whole class]
    00:21:39 GALEET: Uh, guys, hey listen up! Can you all do your best to get done with your data in five minutes so that we can actually look at it up here?
    STUDENT: Are we supposed to fill up the paper?
    GALEET: Yeah, that’s ten – ten wells.

    [moving around room to another group]
    00:21:52 STUDENT: So, purple’s the best?
    GALEET: Purple’s the best.
    STUDENT: So, purple’s the best, so we found a purple. Found a couple of reds.
    GALEET: Okay.
    STUDENT: Had a couple of greens, a lot of greens.
    GALEET: Was there any spatial pattern to it?
    STUDENT: Where was that like, one death well that we found?
    GALEET: The what?
    STUDENT: The death well.
    GALEET: The death well? Okay.
    OTHER STUDENT: [unintelligible] In BW2.
    GALEET: Right. In fact, I think BW2 really was well-known as Well G.
    STUDENT: Really?
    GALEET: I think so.
    STUDENT: So yeah, that was the death well that I put earlier.
    GALEET: Okay, I guess you can call it the death well.

    [speaking to the whole class]
    00:22:36 GALEET: So I want to look at the data as a group and see what we can figure out and then hopefully by the end of this you guys can make some decision about whether you think there’s a preponderance of evidence here or not. Okay so my first question is, how many of you feel like you got enough data with just ten wells to prove one way or the other that either the companies were dumping or that that was causing the leukemia cluster? Not so many, right? Joe, your group, or maybe you do.
    JOE: I feel like we could say that they’re definitely dumping because that’s not a naturally occurring chemical. And like, I mean, I’d want to test somewhere completely outside of the area. Like, not – a similar geographic region. A different –
    GALEET: That’s interesting, because do you remember what the fracking companies are saying about finding methane in the water in – right, they’re saying “well, it’s – it’s well-known that this creek has always bubbled methane.” Maybe it has. So I think you’re right, you’d want to test to see if TC is naturally in the Earth, or a non-point source. Okay, but I think in general it’s really hard with just ten wells to say that this is where it’s coming from, this is definitely where it’s going, and this is what it’s causing. So now you get a sense of why the case was so expensive, if all you have is $30,000 to spend on testing, you don’t actually get enough evidence.

    00:23:55 GALEET: So let’s see what we have. Okay, do you see evidence of point sources? Okay, so Ed what do you see?
    ED: I see two point sources. One by the W.R. Grace and one – no, by the leukemia cluster.
    GALEET: Okay. So these guys here, right? Okay and we don’t truly have the – enough points that I was hoping for, but a plume is when a concentrated source of pollution or anything really. If you think of like adolescent boys are point sources of Axe, like the freshmen I’m talking about. And then they create this like, plume of Axe as they like sit in class or walk down the hall, which is unappreciated. But we can look for the plume of TCE by looking at how the concentration changes away from it. So which direction do you think this plume is going?
    STUDENT: Down.
    GALEET: What does down mean, like down?
    STUDENT: Downstream.
    GALEET: Downstream, but it’s not exactly in the river so it can’t go downstream yet.
    OTHER STUDENT: Downwind.
    GALEET: Downwind? It’s not in the air.
    OTHER STUDENT: It goes down with the gravity like from the high place to the low place.
    GALEET: Down in elevation, okay, and which way is elevation dropping?
    00:25:08 STUDENT: [unintelligible]
    GALEET: That way. This is like why I don’t drive with my sister. She’s like, “over there!” Thanks, can you be more specific? Use words like left and right.
    STUDENTS: [talking at once]
    GALEET: South? But south again is right here. Or I don’t know if that’s really south but we’re pretending it is. Southeast? You think it’s going this way? That’s interesting. I actually think it’s going this way.
    STUDENT: That’s what I said.
    GALEET: That is what you said? By ‘over there?’ It’s going over there, that’s what Jill said. Okay, so Jill, what’s your – what’s your evidence of that?
    JILL: Um, the fact that like – and I’m going to say over there again – but this part is not there, it’s all like red and orange which isn’t bad at all but the only parts that have like green and blue are in that –
    GALEET: Yes. I agree. I agree. Okay, [unintelligible student name]
    STUDENT: Wait, which way is the river flowing?
    GALEET: I think it’s flowing this way.
    STUDENTS: [talking at once]
    GALEET: Okay – right, that’s what I was going to say. Joe, you can say that for me.
    00:26:16 JOE: The aquifer is under the river, and it doesn’t necessarily flow in the same direction.
    GALEET: Right. Absolutely true. Okay, um, and then what do you think is going on with this point source?
    STUDENT: It’s going west – west?
    GALEET: You think it’s staying there generally? So do you think that if you tested the, like, soil in this area compared to this area would you find differences?
    STUDENT: Not much.
    GALEET: Or just by looking at this map, how is the surface –land surface here different from the land surface here? Yeah, Jill?
    JILL: Well the land surface up there is a lot more industrialized and there’s not as much like soil. Whereas there it’s more of a forest.
    GALEET: What is it covered with? This is like, my favorite word.
    STUDENTS: [talking at once]
    GALEET: What? Yes, it’s like almost as good as ubiquitous. The word, the word.
    STUDENT: Um, is it impermeable surfaces?
    GALEET: Yeah. Ok, so this is covered with impermeable surface so if dumping happens here, it doesn’t really soak into the aquifer generally, it goes into a storm drain, and then where does the storm drain go? Probably?
    STUDENT: The river.
    00:27:12 GALEET: Directly into the river, so you’re not going to see a plume here because the city sewer system is taking it directly either to the treatment plant or if it overflows, directly into the stream, right? So I think that that’s why you’re seeing that even though Grace would be a point source, um, it’s not contaminating this whole area here and that’s because of the impermeable surface. Yeah?
    STUDENT: Why can’t – right by the river, where there seems to be like…why can’t it be coming from the W.R. grace where it’s impermeable, why can’t that be where it’s entering into the river?
    GALEET: Why can’t this be where it’s emptying into the river? It could be. Like I think that if you had money and could have – like could test additional factors you could pay somebody to walk down and look for one of those outflows right by the river and then test it during a rain event. Like see when it’s raining, if the storm drain is emptying. That would be good. Okay, so there’s a couple minutes left. One of the parts of the lab that I want you to start thinking about is if in fact this is polluted, how would you start cleaning it up? So if this became a super fun site, I think you guys know a little bit about remediation, so I gave you a bunch of options. So read them over, talk to your group about which one you choose. You’ve got to choose like, health and safety over – or not over, but between that and money, so that’s always rough.

    00:28:34 [bell rings]
    GALEET: Alright, have a good day. Uh, take your labs with you and I’ll post the pictures online, we’ll deal with them later.

School Details

Central High School
1700 West Olney Avenue
Philadelphia PA 19141
Population: 2241

Data Provided By:



Galeet Cohen
Science / 9 11 12 / Teacher


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