Unit 4: Pollution. Two Types of Pollution- Point Source and Non-point Source Pollution

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1 PROJ ECT GUT S Unit 4: Pollution Introduction As our world population increases, we are becoming more and more aware of the pollution that humans are causing and its effect on the environment and our health. Much of the information that we have for predicting the future effects of pollution comes from computer modeling. Meteorological data (wind speed, wind direction, climate, and precipitation), types and quantities of pollution as well as locations of the sources of pollution are integrated in computer models. Different factors and strategies contributing to reducing pollution can be tested using these models. Pollution and Complex Systems The spread of pollution through a community, a water source or around the globe is an example of a complex system. Complex systems are comprised of many interconnected parts. As these parts interact with each other, the overall emergent results can be different from just looking at the parts separately. The different parts to a complex system of air pollution might include the cars, how much they are used, the climate of the area, factories and what they are producing, the population size, the plants and trees and the interactions of the chemicals at the molecular level and sources of energy such as sunlight or heat. The list of interacting parts can be very extensive but our goals in this unit are: to expose students to the basics of pollution- what in their community might be causing pollution and what are the factors that effect how much pollution is in their community? for students to recognize why pollution can be studied as a complex system. Two Types of Pollution- Point Source and Non-point Source Pollution Pollution control standards and regulations distinguish between two main categories of pollution- point source and non-point source pollution. Factories, power plants, mines, chemical plants and oil drills are classified as point source pollution because they release pollution into the environment from a specific location. These sources are easily identified and therefore can be monitored and regulated fairly easily. A famous point-source pollution case came when the Exxon Valdez oil tanker hit a reef in the Prince William Sound in Alaska on March 24, It is considered one of the most devastating man-made environmental disasters ever to occur at sea. The region was a habitat for salmon, sea otters, seals, sea birds and the great white shark. Wildlife was severely affected by the oil spill. Both the long and short-term effects of the oil spill have been studied comprehensively. Thousands of

2 PAGE 2 animals died immediately; the best estimates include 250, ,000 seabirds, 2,800 5,000 sea otters, approximately 12 river otters, 300 harbour seals, 250 bald eagles, and 22 orcas, as well as the destruction of billions of salmon and herring eggs. Due to a thorough cleanup, little visual evidence of the event remained in areas frequented by humans just 1 year later. However, the effects of the spill continue to be felt today. Overall reductions in population have been seen in various ocean animals Non-point source pollution includes pesticides and fertilizers that runoff from farms and lawns as well as the exhaust from cars and trucks on the road. These types of sources are not as predictable and have multiple sources, which can make it harder to control. It is easy to understand the issue of Pollution on a local level if we think about the issue of trash. Trash is a form of point source pollution. Trash affects us on a daily basis - Americans produce on average 4.4 pounds of trash per day! At a school or in a community, this can add up quickly. Examples of pollutants: Point source- Chimney Oil spill Roadside trash Non-point source- Automobile exhaust Pesticides There are many questions that we can ask about trash in our community that can be part of a scientific study. What if we recycled more? What are the ways that we can reduce the litter around our community? What affect does more or fewer trash cans have in a school? How molecules move in the air and water Percolate: The action of a liquid (water) passing gradually through small spaces or a porous substance such as soil. Ground and surface water pollution as well as air quality are also important community issues. Pollution from a factory can be released into the air, mix with the other air molecules, then travel a short distance or across continents. If the pollution is released onto the ground, it could soak into the soil and with rain may get washed into a stream or river or percolate into the water table underneath.

3 PAGE 3 The way that air and water pollution get mixed into a community s supply can be through diffusion. Diffusion is the movement of molecules from a high concentration to a low concentration. The molecules are in constant motion and are bumping into each other in what is described as Brownian Motion. These concepts of molecular motion can be modeled by using randomness in the program. Unit Overview In this unit we will discover ways to model different types of pollution and waste in our community. After learning more about computer science topics such as random walks and agent variables, we will be able to develop a more complete agent-based computer model that takes into account information such as: What are the sources and types of the pollution in our community? What characteristics of complex systems can be identified in this example? How does the pollution move through the community? How do humans and other living organisms respond to this pollution? What are the factors that reduce or increase this type of pollution? Does the location of the source in the community make a difference?

4 PAGE 4 Goals for student learning: The primary goal of this unit is to engage students in looking at the world with a scientific perspective. Students will also be exposed to various kinds of simulations used to understand issues associated with pollution in their community. Unit Structure: Week 1: Introduction to Pollution Webform: Students will fill out a 5 question webform on complex systems. Discussion: What is pollution? What are some examples of pollution that exist in our community? How does pollution move through a community? Discussion: Review of Complex Systems. How does the topic of pollution relate to the concept of a complex system? Activity: Random Walks Discussion: How does the concept of Random Walks apply to other scenarios? Why is random an important part of computer models of complex systems? Activity: Litterbug Starlogo TNG models- student will program in the breeds and their movement in this model. Presentation: Agent Variables- how they are used and why they are important to computer modeling. Activity: Add an agent variable to Litterbug that includes the concept of time an agent holds a piece of trash before either encountering a trash can or throwing it on the ground. Investigations Form: Ask students to use the Unit 4 week 1 investigations form on the Project GUTS website to document their work during the first week of the unit on Pollution. Assignment: Ask parents/guardians and community members about pollution in our community. Write a list of the types of pollution that is mentioned. What are the sources of these examples of pollution? What can be done about it?

5 PAGE 5 Week 2: Exploring models of Pollution Discussion: What is diffusion? How does it relate to water pollution? Activity: Observations of diffusion of a dye molecule in water. How does diffusion relate to complex systems? Discussion: Brownian Motion and how it relates to air pollution. Activity: Brownian Motion Applet Applets/brownian/brownian.html Activity: Starlogo TNG model of a factory and the air pollution. Students will modify the computer model to fit their understanding of air pollution or water pollution in a community. Investigations Form: Ask students to use the Unit 4 week 2 Investigations on the Project GUTS website to document their work during the second week of the unit on Pollution. Assignment: What are the sources of water or air pollution in your community? Blog: What are your ideas for a Starlogo TNG model of Pollution? How is it incorporating aspects of a complex system? Week 3: Implementing alterations to existing models *Depending on time and facilitator availability, students will either be guided through making changes to the existing model to reflect local conditions or experiments they ran with their classmates or will be presented with a model that has been changed to their specifications. Discussion: How would you use this model to run experiments? What are the variables that need to be considered in the situation that you chose? Activity: Use the altered model to run experiments and collect data. Activity: Concept Map of Pollution- Prompt to be announced. Investigations Form: Ask students to use the Unit 4 week 3 Investigations on the Project GUTS website to document their work during the third week of the unit on Pollution. Blog: What type of pollution have you chosen to study? Why is this of interest to you?

6 PAGE 6 Week 4: Analysis and Presentation Activity: Analyze Data Activity: Prepare Presentation of experiments and findings. Activity: Practice presentation before club members Blog: Fill in information about your model onto the Project GUTS website. Investigations Form: Ask students to use the Unit 2 week 4 Investigations on the Project GUTS website to document their work during the fourth week of the unit on Pollution. This topics on this form will be used during the Student Roundtable (if applicable). Discussion: What is the difference between local and global information? What are examples of local and global information in an emergency situation? Web Resources: