Agenda for the Day · Web viewDay #3 Groundwater 8:30Loose ends from previous Day 8:45Scientific Practices: Explanations and Argument 9:15Introduction to groundwater Student thinking

Groundwater

ContentsAgenda for the Day......................................................................................................................................2

Upper Anchor for Soil Water and Groundwater..........................................................................................3

Learning Progression Levels for Groundwater.............................................................................................4

Examples of Student Responses to Groundwater FAs.................................................................................6

Student Learning and Instructional Activity Table: Exploring Groundwater..............................................10

Exploring Groundwater Activity Sequence................................................................................................11

Student Learning and Instructional Activity Table: Exploring Groundwater - Completed.....................12

Scientific Practices and Instructional Activities: Groundwater..............................................................13

Teacher Practices and Instructional Activities: Groundwater................................................................15

Exploring Groundwater Activity Sequence................................................................................................17

Activity 1: Permeability..........................................................................................................................21

Activity 2: Exploring With Groundwater Models...................................................................................24

Activity 3: Application Assessment: Where Would You Drill A Well?....................................................35

Activity 4: Get the Groundwater Picture...............................................................................................38

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Agenda for the Day

Day #3 Groundwater

8:30 Loose ends from previous Day

8:45 Scientific Practices: Explanations and Argument

9:15 Introduction to groundwater Student thinking about soil and groundwater Upper anchor for soil and groundwater

9:45 Break

10:00 Groundwater Formative Assessments Version #1 Version #2

11:00 Permeability Activity & Tools for Reasoning Pathways Tools Drivers and Constraints Tools

11:30 Lunch

12:15 Groundwater Models

1:45 Get the Groundwater Picture

2:45 Break

3:00 Continuation of Milltown Issue

4:00 School year project activities

4:30 Done

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Upper Anchor for Soil Water and GroundwaterStructure of the Soil/Groundwater System: The soil and rocks undergrounds are heterogeneous. There are different soil horizons and stratigraphic layers that have different porosity and permeability values. Aquifers above impermeable layers (open to the surface) are unconfined. Aquifers below impermeable layers are confined.

Macroscopic to Microscopic Scale: Water underground is stored in cracks and small spaces between sediment grains. When water fills the pore spaces completely, the sediment is saturated. The top of the saturated zone is the water table.

o The capacity of geologic materials (e.g., soil, sandstone, shale) to hold water is determined by the porosity of the material. Porosity is the volume of the pore spaces and cracks. Smaller grain sizes have higher porosity (e.g., clay, shale). Larger grain sizes have lower porosity (e.g., gravel).

o Permeability is a measure of the ability of a porous material to allow fluids to pass through it. Permeability depends on the connectedness of the pore spaces in materials. Larger sediment grain sizes (e.g., gravel, sandstone) = higher permeability. Smaller sediment grain sizes (e.g., clay, shale) = lower permeability. If water is able to flow (or be pumped) into and out of the saturated zone of a material at a rate that is useable by people (i.e., if the material is sufficiently permeable), it is called an aquifer. Impermeable layers are called aquitards or aquicludes.

Large (Landscape) Scale: Stratigraphic layers can cover great distances underground. In unconfined aquifers, the top of the water table generally follows topography. Therefore, surface water divides are usually also groundwater divides.

Processes in Watersheds: Water infiltrates into the small pore spaces between grains of sediment or into cracks in crystalline rocks, displacing the air that is in those spaces. Water can move through permeable materials in both horizontal and vertical dimensions. Water can leave the soil/groundwater system where the water table intersects the surface, when wells pump water from aquifers, by being absorbed into plant roots and transpired back into the atmosphere, or where soil water is close to the surface, by being evaporated directly into the atmosphere.

Scientific Principles: Water moves into, through, and out of the soil and groundwater system according to scientific principles.

Drivers:o Gravity This force is the main driver in unconfined aquifers and is the reason why

in general, groundwater follows surface topography.o Pressure (also called hydraulic head). This driver is important in confined aquifer

systems because the fluid pressure may be greater than gravity. Water moves from areas of high pressure (high potential energy) to areas of low pressure (low potential energy). This driver can move water in any direction, including pulling water upwards in wells or pushing it upwards in artesian springs.

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o At the microscopic scale, capillary forces are important. Adhesion between organic material in soil and water molecules, and surface tension (cohesion between water molecules) causes water within the small pore spaces to move upwards or to dry surfaces.

Constraints: The rate and volume of infiltration is constrained byo Permeability – Higher permeability results in higher infiltration.o Porosity – Water will not infiltrate into saturated areas.o Vegetative cover – More vegetation may slow down runoff and increase

infiltration rates.

Representations: Stratigraphy is represented on cross-sections. Soil and groundwater can be modeled and represented using cross-section diagrams.

Dependency & Human Agency: Infiltration and aquifer recharge rates can vary from a few feet a day to only inches per year. Therefore, in many areas, withdrawal of water from aquifers can result in a drop in the water table.

Learning Progression Levels for GroundwaterLevel 4: Model-Based AccountsLevel 4 accounts trace water into and out of the soil/groundwater systems at multiple scales and along multiple pathways, include reference to driving forces and constraining variables that define possible pathways for water underground, use representations such as cross-sections to trace water, and consider implications of human connections to groundwater systems.

Level 3: School Science AccountsLevel 3 accounts tell school science stories about groundwater. They trace water into the soil and eventually into groundwater or aquifers along multiple steps and pathways. Structure & Systems: Accounts recognize that water underground is in pore spaces, although the scale of these pore spaces may be too large or too small. They recognize that the groundwater and surface water systems are connected, although accounts are more likely to describe water infiltrating into the ground and are less likely to trace water from an aquifer into surface water (e.g., a river) unless specifically prompted. Scale: Can trace water underground at landscape scales. May not recognize scale of pore spaces in underground systems.Scientific Principles: Accounts usually names processes such as infiltration. They do not consider how gravity, pressure, or permeability constrain water movements.Representations: Can trace water through cross-sections, but do not usually reason about constraining factors on groundwater flow. Thus, they may trace water through the groundwater across watershed boundaries in unconfined aquifer systems even though this is an unlikely path.Dependency & Human Agency: Recognizes that human actions have impacts on environmental systems. May reason that pumping from wells can impact the water level in aquifers. May not recognize in principled ways the limitations of human agency.

Level 2: Force-Dynamic Accounts with Mechanisms

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Compared with level 1, level 2 accounts show an expanded awareness of and experience with the physical world. These accounts provide more sophisticated force-dynamic explanations and predictions about water. Most significantly, mechanisms to move water or change water are included (compared with level 1, in which no mechanisms are included).Structure & Systems: Level 2 pictures show water in open spaces underground, such as in underground rivers, lakes, or caverns. Often depicts wells as the iconic stone cylinder with a bucket and rope (Jack & Jill well). May not recognize how surface and groundwater systems interact.Scale: Focus is on visible macroscopic scale at familiar distances.Scientific Principles: Includes mechanisms for water moving into the soil or ground. Mechanisms describe agents (often inanimate things in natural systems) doing something to the water, such as the ground absorbing the water. Accounts may also describe natural tendencies of water (sinking into the ground) or describe familiar experiences, such as water and dirt will make mud. Accounts may refer to special circumstances, such as groundwater may get into a bathtub if the bathroom is in the basement. For example, river water can enter a well if the river overflows into the top of the well.Representations: Recognizes limited connections between representations and the physical world. For example, reasons about maps in two dimensions (horizontal) but does not consider the third (vertical) dimension. May describe cross-sections.Dependency & Human Agency: Humans benefit or are impacted by movements of water underground if the conditions are right.

Level 1: Force-Dynamic AccountsLevel 1 accounts of water focus on water in visible systems at macroscopic scales. At this level, accounts explain that water goes into the ground, but once that water is no longer visible, the water is considered to be gone, or to have essentially disappeared. Structure & Systems: Drawings of underground systems tend to depict water in tanks or pipes only. They provide anthropocentric sources for groundwater, such as from toilets or sewers. Scale: Accounts focus on macroscopic, visible water or water in familiar places. Scientific Principles: Accounts do not trace water into other systems. Accounts may say that water “goes” into the ground, but do not say how or what happens to the water once it gets there. Typically, the view is that water that goes underground is not re-available for use.Representations: Drawings of water underground show water in pipes or tanks.Dependency & Human Agency: These accounts portray people as the sources and movers of water underground.

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Examples of Student Responses to Groundwater FAs Student Drawing Level Notes on levels or

foci for instruction

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Student Learning and Instructional Activity Table: Exploring GroundwaterWhat students need to work on (Foci for instruction)

Permeability Groundwater Models & Where to put a well

Get the Groundwater Picture

Structure & Systems:

Scale

Scientific Principles

Representations

Dependency & Human Agency

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Exploring Groundwater Activity SequenceActivity/Description Learning Goals – Practices fused with

contentFormative Assessments

Drivers & Constraints Representations Tools

Permeability

Students pour water into cups of gravel, sand, and clay to see what happens to the water.

- Investigate and analyze and interpret data about permeability

- Construct explanations for groundwater infiltration rates

Groundwater 1Groundwater 2

- Gravity pulls water down;

- Permeability constrains infiltration rates

Physical models - Drivers & Constraints tool to reason about permeability rates

Exploring with Groundwater Models

Students use groundwater models to investigate groundwater movement

- Use models to explore groundwater systems

- Investigate and analyze and interpret data from wells

- Construct explanations about water movements in groundwater systems


- Gravity pulls water down; pressure pushes water to areas of low pressure


- Physical models- Cross-section

diagrams

- Drivers and Constraints tool to reason about possible pathways for water underground

Where would you put a well?

Given a map/cross-section, students are asked to suggest a location for a new well

- Investigate and analyze and interpret data about wells

- Construct arguments from evidence about where to locate a well




Cross-section diagrams



Students use well data to construct a cross-section and then use the cross-section to analyze the groundwater system.

- Use cross-section representations to locate and trace water in the groundwater system

- Analyze and interpret well log data to predict groundwater movements

- Construct predictions for water movements through a groundwater system




Cross-section diagrams


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Student Learning and Instructional Activity Table: Exploring Groundwater - CompletedWhat students need to work on (Foci for instruction)

Permeability Groundwater Models & Where to put a well


Structure & Systems:

Recognizing that water exists in cracks and pore spaces (L2 to L3)

Recognizing connections between surface and soil/groundwater systems (L2 to L3 and L3 to L4)

Investigate location of water in different sediments (L2 to L3)

Investigate and trace movement of water through underground systems (L2 to L3 and L3 to L4)

Trace water through underground systems (L2 to L3 and L3 to L4)

Scale

Describing groundwater systems at landscape scales (L2 to L3)

Recognizing scale of pore spaces in underground systems (L3 to L4)

Examining the size of pore spaces and the influence on permeability rates (L2 to L3 and L3 to L4)

Investigating water movements through pore spaces at the macroscopic scale (L2 to L3 and L3 to L4)

Tracing water through underground systems at landscape scales (L2 to L3)

Scientific Principles

Moving from force-dynamic agents to processes of infiltration to describe water movements (L2 to L3)

Moving from naming processes to considering drivers (gravity & pressure) and constraints (permeability) on processes to move water in underground systems (L3 to L4)

Investigate permeability of different sediments (L2 to L3 and L3 to L4)

Using scientific principles to explain water movements and to predict the best location of a well (L2 to L3 and L3 to L4)

Writing Accounts (Explaining & Predicting) of water pathways (L2 to L3 and L3 to L4)

Tracing water through underground systems (L2 to L3)

Considering the influence of gravity, pressure, and permeability to trace water through underground systems (L3 to L4)

Writing Accounts (Explaining & Predicting) of water pathways (L2 to L3 and L3 to L4)

Representations

Using cross-sections to trace water in underground systems ( L2 to L3)

Reasoning about drivers and constraints from cross-sections (L3 to L4)

Drawing cross sections and using cross-sections to explain, predict, and make arguments (L

Using cross-sections to trace water and explain, predict, and make arguments about water flow (L2 to L3 to L4)

Dependency & Human Agency

Recognizing how humans impact and are impacted by movements of water underground (L2 to L3)

Recognizing the limitations of the groundwater

Using cross-sections to explain and predict groundwater movements and well locations (L2 to L3

Using cross-sections to trace water and explain, predict, and make arguments about water flow (L2 to L3 to L4)

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system to provide fresh water (L3 to L4). to L4)

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Scientific Practices and Instructional Activities: GroundwaterWhat Students Need to Work On (Foci for Instruction)

Permeability Groundwater Models & Where Would You Put Well


Prac

tices

Using Models Using models to develop understanding of an otherwise invisible system (i.e., groundwater).

Using models to develop understanding of particle size, permeability, and water movement.

Using groundwater models to explore this system. Drawing and interpreting cross-section diagrams of groundwater system.

Constructing cross-section of groundwater system to develop understanding of groundwater flow.

Investigating, Analyzing,Interpreting Data

Using first-hand experiences with models of sediments and the groundwater system to explore, analyze & interpret how water flows through the ground.

Testing with different sediment/particle sizes to investigate permeability through different materials.

Interpreting observations/data of pumping in a groundwater model to make inferences about locations of hidden well bottoms.Analyzing cross-section to decide where to build a well.

Students us well data to construct a cross-section and then use the cross-section to analyze the groundwater system.

Constructing Explanations

Moving from force-dynamics & informal rules to considering drivers (gravity, pressure) & constraints (permeability, statigraphy) to explain movement of water in ground.

Using D&C Tool and constructing explanations about drivers and constraints that govern permeability of different materials.

Using D&C Tool to explain how gravity and pressure drive groundwater and how permeability and statigraphy constrain groundwater. Applying explanations in “Where would you put well?” assessment.

Students can construct explanations of where water flows in the represented cross-section.

Arguments From Evidence (& Social Construction)

Developing, defending & evaluating arguments & explanations using experience, evidence & scientific principles in social context (i.e., peer to peer).

Sharing permeability explanations with peers.

Developing, sharing, defending, and evaluating with peers arguments about where well bottoms are located and where to build well.

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What Students Need to Work On (Foci for Instruction)

Permeability Groundwater Models & Where Would You Put Well


Cros

s-Cu

tting

Con

cept

s

Scale, Proportion & Quantity

Relating size of sediment particles to permeability, and permeability to groundwater movement.

Investigating how size of sediment relates to permeability.

Developing understanding of size of pore spaces underground (generally not large open lakes or rivers).

Translating between scale of cross-section diagram and scale in real world.

Systems & System Models

Developing understanding of groundwater system (which is usually invisible to us).

Examining groundwater system materials in macroscopic scale model, which can then be extrapolated to larger scale groundwater systems.

Developing understanding of the structure of groundwater systems using a small-scale model.

Developing understanding of the structure of groundwater systems through constructing and using a cross-section diagram.

Flow & Conservation of Matter

Tracing water into, through and out of the groundwater system.

Examining water flow through different sediment sizes.

Connecting structure of groundwater systems to how water flows into, through and from groundwater system.

Using a cross-section diagram to consider groundwater flow through different materials.

Stability & Change Recognizing how groundwater is

recharged and how natural events (e.g., drought) and human actions (e.g., pumping of groundwater) can change the amount of groundwater that is available.

Examining how quickly water can be infiltrated or extracted from different sediment types.

Examining how pumping of groundwater can impact amount and movement of water in groundwater system.

Examining how groundwater system can change through actions such as pumping and/or introducing pollutants.

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Teacher Practices and Instructional Activities: GroundwaterPermeability Groundwater Models & Where

Would You Put WellGet the Groundwater Picture

Formative Assessment Groundwater Formative Assessment Use this formative assessment to identify students’ initial ideas about what the groundwater system looks like and how water moves through the groundwater system. Some students may think groundwater exists in underground pipes or tanks (level 1) or in open areas underground such as underground lakes or rivers (level 2). Some students may think that groundwater is a dead end where water goes and never comes out (level 2). The Student Learning and Instructional Activities table on p. 12 provides ideas for using the activities to support students to develop understandings related to this formative assessment. Further suggestions are also provided in the formative assessment teacher materials.

Tools for Reasoning Use the D&C Tool to help students reason about drivers and constraints that govern how water moves differently through different types of sediment.

Use the D&C Tool to help students explain drivers (gravity, pressure) and constraints (statigraphy, permeability) for how water moves into, through and out of groundwater system.

Use Pathways Tool to help students develop understanding of multiple pathways into, through, and out of groundwater system.

Use D&C Tool to help students consider drivers and constraints acting on different layers of the groundwater system.

Supporting Explanation Use the Drivers & Constraints Tool and application questions in activities (e.g., Where would you build a well?) to press students to not just DESCRIBE WHAT will happen, but to also EXPLAIN HOW AND WHY events and processes in groundwater systems happen.

Social Construction of Understanding

Use participatory and collaborative teaching strategies to engage students in co-constructing their understanding. When you use formative assessment at the beginning of a unit or lesson, allow students to share their

different ideas about “what, how and why” questions, but do not give the correct answers at this point. Write down different students’ ideas in a public place so they can be revisited throughout the unit (e.g., during investigations and further development of explanations).

During investigations and other activities, have students work in small groups first to share their ideas and construct their explanations. Students may feel more comfortable sharing ideas if, initially, they are not asked to share in front of the whole class. Working in small groups, students also have the opportunity to learn from each other, and not just from the teacher. They also have the opportunity to question each other’s ideas.

After students have worked in small groups, provide opportunities for groups to share their ideas and explanations with the whole class (e.g., completed tools, written explanations for application questions). If possible, use a document camera or other way to display groups’ responses so they can be seen by the whole class. Rather than evaluating students’ answers as the teacher, ask the students to consider and evaluate each others’ ideas and explanations. Do they agree or disagree? Why? Encourage students to be respectful when

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they disagree. Scientific argumentation is a central practice that scientists engage in every day. Providing opportunities for

students to engage in scientific argumentation with peers supports development of a core scientific practice. Students learn that science is not just a body of facts to be learned from a textbook or a teacher. Rather, science is a process of learning about the world that scientists engage in together as a collaborative and critical community.

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Exploring Groundwater Activity SequenceSummary of ActivitiesActivity 1: PermeabilityStudents pour water into cups of gravel, sand, and clay to see what happens to the water. This activity is similar to Part I of the “Get the Groundwater Picture” activity in Project Wet.Activity 2: Exploring With Groundwater ModelsStudents use groundwater models to investigate groundwater movement through different sediment types and gain knowledge of how wells impact water resources. Activity 3: Well Problem – Where would you put a well?Given a map/cross-section, students are asked to suggest a location for a new well and justify their answer based on the features on the map and cross-section.Activity 4: Get the Groundwater PictureStudents use well data to construct a cross-section and then use the cross-section to analyze the groundwater system.

Learning GoalsThese activities help students explore the following questions.

1. Where is water underground?2. How does water get into the ground and what affects how much water infiltrates into

the ground?3. How does water move underground? How does water move out of the ground?4. How deep is the well (investigation question)?5. Where should you put a well?

Scientific Practices with Content1. Students will ask questions about groundwater structure and processes.2. Students will use models of groundwater systems to investigate structure and processes

in groundwater, including driving forces and constraining factors that govern how groundwater moves.

3. Students will analyze and interpret data about the permeability of different substrate materials and impacts of well pumping on different places within a groundwater system.

4. Students will construct explanations for groundwater processes including infiltration, groundwater flow, and well pumping using understanding of groundwater structure, driving forces of gravity and pressure, and the constraining factor of permeability.

5. Students will make arguments from evidence about where hidden well bottoms are located based on observations of two different wells pumping water. Students will also make arguments from evidence about where the best place to build a well is given a cross-section scenario problem.

6. Students will evaluate each other’s arguments about groundwater scenarios and communicate their own arguments.

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Crosscutting Themes1. Students will observe patterns in type of substrate material and level of permeability to

make inferences about how groundwater system processes will work in particular contexts.

2. Students will understand that there is a causal relationship between human pumping at the surface and the level of the water table below the ground.

3. Students will understand the role of scale of particle size in impacting permeability, and apply this relationship to explaining groundwater flow in large-scale groundwater systems.

4. Students will develop understanding of groundwater as a system connected to the surface water systems using physical system models.

5. Students will develop understanding of groundwater flow through explorations with models.

6. Students will develop understanding of groundwater system structure and function through exploration with models.

7. Students will develop understanding of how human actions can change the quantity of groundwater present in aquifer systems.

Elements of the Learning Progression1. Structure of Systems: Structure of the soil/groundwater system2. Scale: Macroscopic (but hidden) to landscape3. Scientific Principles

DriversGravity – Water infiltrates downward into the ground due to the pull of gravity.Pressure – Water moves from areas of high to low pressure underground. Wells work by changing pressure within the well shaft. In the case of shallow wells (less than 20 meters deep), wells work by decreasing pressure at the top of the shaft, so that water moves from an area of higher pressure down below, to an area of lower pressure at surface. In the case of deep wells (greater than 20 meters), well pumps use a compressor to increase pressure at the bottom of the well, which results in water moving to the area of lower pressure at the surface.Capillary action – Water will move upwards through small spaces between sediment particles. Capillary action works through a combination of surface tension caused by cohesion within the water and adhesion of water molecules to sediment particles. Note: You may not want to address drivers of pressure and capillary action with students operating at levels 1 and 2 on the learning progression. Focus on gravity as the driver with these students, and consider pressure and capillary action with students who show readiness to move from level 3 to level 4.

ConstraintsPermeability – Permeability is a measure of the ability of a porous material (such as unconsolidated sediments underground) to allow fluids to pass through it. Gravel is more permeable than sand. Clay and shale are not very permeable, such that for practical purposes they are impermeable (do not allow fluids to pass through). Groundwater movement is thus constrained by permeability of the material that the

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water is moving through. Water generally moves much more quickly through permeable substrates such as gravel, and more slowly through substrate materials that are less permeable.

4. RepresentationsCross-section diagrams

5. Human Dependency and Change: The volume of groundwater available for use is limited. People may pump water from the ground faster than it can recharge, effectively mining the water. Changes in surface cover can change the permeability of the ground, limiting infiltration and recharge rates. People can also pump water into the ground to store water for later use.

Formative AssessmentsUse Groundwater Formative Assessments #1 and #2 to assess student level of achievement for understanding structure of the groundwater system and pathways of water underground.

1. Hold up a glass of tap water. Explain that in some communities (maybe your community), the tap water comes from underground.

2. Ask students to think for a minute about how it could be possible that people can get water from the ground. What does it look like underground? Where is the water? How does the water get underground? How do people get the water out of the ground?

3. Distribute a Groundwater Formative Assessment sheet to each student and have students complete it.

Target Explanations and ReasoningWhere is water underground?The soil and rocks underground are heterogeneous. There are different soil horizons and stratigraphic layers that have different porosity and permeability values. Impermeable layers are called aquitards or aquicludes. Water underground is in pore spaces and cracks. Aquifers above impermeable layers (open to the surface) are unconfined. Aquifers below impermeable layers are confined.

How does water get into the ground and what affects how much water infiltrates into the ground?Water infiltrates into the ground because gravity pulls water down. The water infiltrates into the pore spaces between grains of sediment or into cracks in crystalline rocks, displacing the air that is in those spaces. The volume of water that can infiltrate into and out of the soil and groundwater is determined by the connectedness of the pore spaces (permeability). Larger sediment grain sizes (e.g., gravel, sandstone) have higher permeability. Smaller sediment grain sizes (e.g., clay, shale) have lower permeability.

How does it move underground? How does it get out of the ground?Water moves underground in response to gravity and pressure. In unconfined aquifers, water moves downwards in response to gravity. In confined aquifers, water moves from areas of high pressure to areas of low pressure. Water leaves the underground system into a lake, river, or spring when an unconfined aquifer intersects the ground surface. Water can also leave either an unconfined or confined aquifer when pressure in a well draws the water upwards.

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Which Well is Deepest?Well B is shallower because eventually it pulls out blue water from the lake. Well B is in the unconfined aquifer. Water from the lake infiltrates into the unconfined aquifer because gravity pulls it downwards. As well B is pumped, it creates a zone of low pressure and the water in the well moves upwards. This situation then creates low pressure at the bottom of the well and water from the aquifer moves into the well. Since the unconfined aquifer connects to the lake, pumping from this well eventually pulls water from the lake into the well. Well A does not pull out blue water. The reason is because the well is in the confined aquifer, which is below an impermeable layer. When water infiltrating down from the lake meets the impermeable clay layer, it cannot move through the clay because the pore spaces in the clay are so small that the water does not move through quickly. Therefore, the water from the lake cannot infiltrate into the gravel below. Pumping from well A does not affect the lake.

Where would you put a well?A well next to the house above the impermeable layer will be cheapest to drill because it will be shallow. A well in this location will be susceptible to running dry because some of the recharge area is covered by the impermeable Cherry Lane pavement. A well near the house but below the first impermeable layer or a well near the river will have a more reliable recharge from the river. If the well is close to the river, it may have contamination problems from the river. A well near the house into the lowest gravel layer will be most expensive. It will be least susceptible to contamination. However, recharge may be very slow, if at all, and the well could be susceptible to going dry.

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Activity 1: PermeabilitySummary of ActivityStudents pour water into cups of gravel, sand, and clay to see what happens to the water. This activity is similar to Part I of the “Get the Groundwater Picture” activity in Project Wet.

MaterialsFor each group:

1 clear plastic drinking cup filled with gravel 1 clear plastic drinking cup filled with powdered clay 1 clear plastic drinking cup filled with play sand 1 plastic cup of water 3 eye droppers or plastic pipettes with narrow tips. Graduated cylinder for water or another cup with approximately 20 ml marked on the

side.For each student:

Science notebook and pencil Drivers and Constraints Tool in student pages below

Activity ProceduresQuestion: Establish a question and elicit student ideas1. Divide students into groups of 3 to 4 and provide each group with 1 cup of gravel, 1 cup of

sand, 1 cup of clay, 1 cup of water, 3 additional cups with 20 ml marked on the side of each, and 3 pipettes. If graduated cylinders are unavailable, provide another plastic cup or beaker with approximately 20 ml marked on the side of the cup.

2. Have students pour 20 ml of water into each of the empty plastic cups.3. Explain to students that they will be pouring 20 ml of water into each sediment cup. Before

they pour the water into the cups of sediment, have students write in science notebooks and share with their group their initial ideas about the following questions.

a. In which cup will the water infiltrate (soak in), the fastest? Why?b. In which cup will it be easiest to get water out? Why?

Explore & Investigate: Explore patterns in phenomena 4. Have students pour 20 ml of water into each sediment cup. You may direct

students to pour the water on all cups at the same time.5. Have students observe where the water goes in each cup and record their

observations. Prompt students to make careful drawings of the water in the pore spaces in each of the three sediment cups. Support students in seeing the pattern that the larger the grain size of the sediment, the faster the water moves through.

6. Have students use the pipette to try to pull water out of each of the three cups of sediment. Which cup is easiest to pull water out of? Why? Support students in noticing the same pattern – the larger the grain size the easier it is to pull water out of the cup.

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PracticesUsing Models

PracticesAnalyzing & Interpreting Data

Explain: Introduce scientific ideas and explain patterns7. Introduce the term infiltrate - to move into and through.8. Define permeability - how easily water moves through the pore spaces. Permeability is

relative. Gravel has a greater permeability than sand. Clay and shale have a very low permeability, to the point that for practical purposes, they are impermeable.

9. If necessary provide the following analogy: Imagine a room filled with beach balls. How much space is between the beach balls? Would water flow through these spaces easily? We would say this room is permeable. Now imagine a room filled with golf balls. How much space is between the golf balls? It would be harder for the water to flow through the golf balls. We would say this room is less permeable than the room with beach balls. Now, imagine a room filled with ball bearings. There is still space between the ball bearings, but they are very, very tiny. It would be much harder, and take much longer for the water to flow through the ball bearings than the beach balls. This room would be even less permeable. If the room was filled with clay or concrete, water would not flow through the room, and the room would be impermeable.

10. Have students return to their initial ideas about in which cup the water would infiltrate the fastest. Support students in recognizing the pattern that water infiltrates (i.e., moves through) into sediment with larger pore spaces faster than sediment with smaller pore spaces. Sediments with larger pore spaces are more permeable than sediments with smaller pore spaces.

11. Have students, in their groups, complete the Drivers and Constraints Tool shown below. After groups complete their tools, engage the class in a discussion to ensure students understand the role of gravity as a driver and the role of permeability as a constraining factor in water moving through different materials. Students should also understand the pattern in permeability levels for sand, gravel and clay.

12. Assign each group one of the following questions to construct an explanation about using claims, evidence and reasoning. Make sure each of the questions is addressed by at least one group. After students complete their explanations, have them share with the class and check to make sure all students understand and are able to explain the patterns using claims, evidence and reasoning.

a. Which type of material does water flow through the fastest? Water moves through gravel the fastest. As gravity pulls water down, it moves quickly through the gravel because gravel has the largest and most connected spaces between particles for water to move through.

b. Which type of material does water flow through the slowest? Water moves through clay the slowest. The clay has the smallest and least connected spaces between particles. Water does not move through these spaces very quickly (Note: clay also has adhesive properties that hold the water in place as well)

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Practices Constructing

Explanations

Making arguments from evidence

Students can complete this activity using their science notebooks and the Drivers and Constraints Tool (example included below).

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Activity 2: Exploring With Groundwater ModelsSummary of ActivityStudents use groundwater models to investigate groundwater movement through different sediment types and gain knowledge of how wells impact water resources.

MaterialsFor class:

Document camera LCD projector or SmartBoard Half a cup of water with two drops of blue food coloring in it One groundwater model for initial demonstration

For each group: A groundwater model A container labeled “storage tank” to pump water into (e.g., recycled plastic lettuce bin) A rain cup (paper cup with holes punched on bottom for raining on model) A beaker or small container of water Water source (sink or jug of water) A rag or reusable towel available for spills

For each student: One blank Drivers and Constraints Tool One “Exploring With Groundwater Models” handout Pencil

Activity ProceduresQuestion: Establish Questions and Elicit student ideasPart 1 (Day 1)1. Before class begins, write the four questions in procedure 3 below in four columns on the

whiteboard. 2. Begin class with a short review of the permeability activity. Ask students:

a. What did they find out about sand, gravel and clay?b. What did their investigation with sand, gravel and clay have to do with

groundwater?3. Next review students’ ideas about groundwater using the questions written on the board in

a whole class discussion. Ask multiple students to share their ideas for each question. Record students’ ideas on whiteboard as they share.

a. What does it look like underground where there is water?b. How does water get into the ground?c. How does water move underground?d. How can water get out of the ground?

4. Put students into groups of four and give one “Exploring With Groundwater Models” handout to each student.

5. Set a groundwater model at the front of the class. The model should be prepared so that the lake in the center is partially filled. Have each student draw the cross section of the groundwater model on page 1 of their handout. Explain to students how the fold line works

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and how they should draw what they see from a top view in the top part of the box, and how they should draw what they see in the cross-section view in the bottom part. Students can come to the front of the class to see the model more closely, including both the side and the top. Students should label on their drawings: different layers of material, the wells (in top view only), the lake from top and side, and water they see in the model.

Group Work with Drivers and Constraints Tool and Pathways Tool – Where will water go?6. Establish the question: Where does water go? 7. Have students make predictions about where, how, and why water flows in the model.

Show students the rain cup and explain that soon there will be a rain storm over the ground. Ask students to use the Drivers and Constraint Tool to predict where they think the water will go. Encourage students to think about drivers (gravity, pressure) and constraints (permeability). Have students write their predictions, including reasons, on the back of their completed tool

8. Have students share their predictions. 9. Students may also use the Pathways tool to make their predictions about where the water

will go.

10. Establish the driving question: Which well goes deepest? Students may make initial predictions.

11. Next, conduct the first investigation with the groundwater models as a demonstration that students need to reason about in their small groups. Note that students will not know where the bottom of the two well tubes are located, and will need to figure this out based on the demonstration. The teacher should know, though, that the wells are configured as shown in the diagram below.

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Practices:Using Models

Explore & Investigate: Explore phenomena for patterns12. Show students the water with blue food coloring and tell them that this water represents

the most recent rain. Pour the water into a rain cup and rain over the groundwater model, making sure some of the tinted water gets in the lake. Tell the students that each of the two wells (A and B) is a solid tube that’s open at the bottom with a filter over it. Show students an example of a well tube with a nylon filter over it. Tell students that you are going to pump 12 times from each well pump. Based on their observations from the pumping, students will need to decide in which layer they think the bottom of each well is located.

13. Ask students to observe carefully as you conduct the investigation. First, pump 12 times from Well A into the storage container. The water that is pumped out should remain clear. Show students the clear water. Dispose of the water from the storage container. Next pump 12 times from Well B. The water that is pumped into the storage container should have some blue tint to it. Show the blue-tinted water to the students. Based on this observation, in their small groups, students should develop arguments for where they think the bottoms of Well A and Well B are located. Ask students to complete page 2 of their handouts.

14. Next tell students that each group will get a groundwater model to work with. Ask students what they should remember when working with the models (e.g., they’re fragile and should be used with care, pump the wells gently, allow each student a chance to explore with the model, etc.). Next pass out a groundwater model, storage tank, rain cup, container of water,

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Practices: Analyzing &

Interpreting Data

Constructing Arguments from Evidence

Practices:Using Models

and rag to each group. Students should explore with their model for about 10 minutes and complete the questions on page 3 of their handout.

15. Collect student handouts and review before second part of lesson on next day.

Part 2 (Day 2)Explain: Introduce Scientific Ideas and students explain patternsReview Cross-Section Diagram and Introduce Terms1. Write following terms on board:

a. Permeabilityb. Infiltrationc. Groundwater flowd. Water tablee. Unconfined aquiferf. Confined aquifer

2. Return students’ handouts and project the cross-section diagram WITHOUT WELLS on the next page onto the Smartboard, or draw a similar diagram on whiteboard. Students have their diagrams on their handouts to look at and refine.

3. Review permeability with students. Draw pictures of sand, gravel, and clay particles on board. Define permeability as the ability of a material to allow fluid to pass through. Talk about water residing and passing through spaces between particles of sand, gravel and clay. Ask whether clay is permeable at all? (Maybe just a tiny bit --- it does get wet).

4. Revisit with students what it looks like underground where there is water. Check their ideas after exploring with the models. Are there open lakes and streams? Where is MOST of the water underground?

5. Revisit how water gets into ground. Ask them to explain what they observed and provide the term infiltration for water soaking from the surface into the ground.

6. Ask students to describe how water moves underground based on their observations. They should describe that it moves between pore spaces in sand, gravel and clay. This is called groundwater flow.

7. With a marker, draw in the lake and extend surface of lake line to left and right to show height of water table (see drawing from Where Would You Drill a Well? assessment for an example of how to draw in water table). Explain to students that the line you drew in is the water table and that that’s the same height as the surface of the lake. Students should draw and label the water table on their own diagrams. Help students understand that below the water table, the ground is saturated with water. Ask the students to talk about how the level of the water table changed during their explorations the previous day.

8. Next explain to students that the area with water in sand and gravel above the clay layer in the model is an unconfined aquifer. An unconfined aquifer is a layer with water that is not below an impermeable layer. Ask the students where the impermeable layer is and how they know (the clay, because water does not move through clay easily). Label the unconfined aquifer on the diagram and have students label the unconfined aquifer on their own diagrams.

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9. Next explain to students that the area below the clay layer is a confined aquifer. A confined aquifer is a layer with water that is below an impermeable layer. Label the confined aquifer on the diagram and have students do the same on their own diagrams.

10. Ask students if they have any questions about the diagram or what the water table is, or what a confined aquifer and an unconfined aquifer are.

Sharing Student Explanations About Well Bottom Locations1. Note: Students will make and support claims and agree or disagree with each

other’s claims. Remind students that they can disagree with someone in a polite way. Scientists participate in arguments about science all the time to work together to learn how the world works. It’s not about being smarter than someone else. Ask students to please be considerate when they share their ideas and when they disagree with another student.

2. Call on a group to come to front of class and draw on the projected diagram how far they think Well A extends down into the ground. The group should explain why they answered the way they did. Ask the rest of the class to agree or disagree by showing thumbs up or thumbs down. If any students disagree, ask them to explain why. Lead a discussion of student ideas (with students responding to each other’s ideas, rather than only having teacher evaluate students’ ideas) and help students come to consensus. Students should understand that Well A is a deep well that extends into the confined aquifer. Because it is mostly separated from the lake by the impermeable layer of clay, pumping from Well A does not have much effect on the lake.

3. Next, call on another group to come to the front of the class and draw on the projected diagram how far they think Well B extends down into the ground. The group should explain why they answered the way they did. Ask the rest of the class to agree or disagree by showing thumbs up or thumbs down. Lead a discussion of student ideas and help students come to consensus. Students should understand that Well B is a shallow well that takes water from the unconfined aquifer above the clay layer. Because it is NOT separated from the lake by an impermeable layer, pumping from Well B has a significant impact on the level of the water in the lake. This discussion should help students understand how groundwater is connected to surface water.

Groups Work on Drivers and Constraints Tools1. Hand out one blank Drivers and Constraints Tool to each student. 2. Project Drivers and Constraints Tool. Discuss what the aspects of the tool mean and how to

use. a. Drivers are forces that move water. Use example of water on a hill that starts on

the side of the hill. If it goes over the ground, which direction will it move? (Down). What’s the force that moves it? (Gravity). The name of this is runoff.

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PracticesMaking Arguments from Evidence

Communicate arguments

Evaluate arguments

b. Constraints are things that limit how or how much something happens. So your parents may limit how much TV you can watch. That’s a constraint. And the law limits you from driving until you’re sixteen. That’s a constraint. With water, constraining factors limit how fast or slow, how much, or in which direction water moves. Use slope as an example. Draw a steep slope and a shallow slope on the board and ask students how these two slopes will affect how fast or slow water moves. Then draw two slopes slanting in different directions and ask students how these two slopes will direct which direction water moves.

c. Next go through an example of a row of the Drivers and Constraints Tool as a class --- use water in sand layer to water in a gravel layer.

3. Students should now return to their lab groups to work together on the Drivers and Constraints Tool.

4. Show the following options for rows of the Tool to think about and work on. Each group should pick two options and use those options to work on two rows of the Tool.

a. Water on the surface (above the ground) Water in unconfined sand layerb. Water in unconfined sand layer Water in unconfined gravel layer c. Water in unconfined gravel layer Water in clay layerd. Water in unconfined sand layer Water in the lake (this one is more

challenging)e. Water in the ground Water being pumped out of a well (If you’d like, talk

about pumping and pressure using the balloon demo*)f. Choose a different starting and ending place

Example Drivers and Constraints Tool responses for teachers are provided on the next page.Example Responses to Drivers and Constraints Tool

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*Balloon Demo For Explaining How Wells Work: Students may have trouble explaining drivers and constraints for how water comes out of a well. Use this balloon demo to help students think about pressure and movement of matter, including water. Fill a balloon with some air and squeeze the end shut so the balloon remains somewhat full. Hold up the balloon and ask students what is the difference between the air inside the balloon and the air outside the balloon (students should be able to describe that the air inside the balloon is more compressed, and that the molecules of air are closer together)? Next, ask the students if they think there is higher pressure inside or outside of the balloon (students should be able to describe that there is more pressure inside the balloon)? Ask the students what they think will happen if you let go of the end of the balloon --- will air move from inside the balloon out or from outside the balloon in? Why? (Students should be able to explain that air will move from inside the balloon out and they should have some ideas to share about why). Release the balloon and allow students to observe that air moves out from the balloon. Next, ask students to apply their explanation to the question of whether matter moves from areas of low pressure to high pressure or from areas of high pressure to low pressure. (Students should reason that matter tends to move from areas of high pressure to low pressure because that is what they observed with the balloon. They may indicate that the molecules of air are pushing against each other.). Finally, ask students to apply what they observed to think about how a well works. The basic idea is that well pumps change the pressure within the well tube so that there is higher pressure at the bottom of the well under the water table and lower pressure at the surface. Because matter moves from areas of high pressure to low pressure, the driver of pressure overcomes the driver of gravity and the water moves up to the surface where it can be used. You can let students know that constraining factors for this process of well pumping include things like the depth of the water table (it takes more pressure to move water a further distance to the surface) and the power of the well pump (a stronger pump that creates more pressure at depth can move water to the surface more rapidly than a pump that creates less pressure at depth).

Whole Class Discussion of Drivers and Constraints Tools1. Lead a class discussion with groups reporting out their responses for the Drivers and

Constraints Tool. Project the completed Tools using a document projector, or have students write their responses for a row on the whiteboard. Discuss one row at a time. Use the agree/disagree (thumbs up/thumbs down) strategy to have students argue about their claims. Make sure you ask students to discuss the reasons for their responses and what evidence they saw that led to their responses. See the sheet in the supporting materials for some suggestions of what reasonable responses might look like for the different options. Help students move toward understanding the Drivers and Constraints for these pathways.

2. Students can edit their responses to the Drivers and Constraints Tool during the discussion. At the end of the discussion, collect each student’s completed Tool.

Student PagesSee below.

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PracticesCommunicate & Evaluate Arguments

Name:Date:

Exploring With A Groundwater Model

1. Draw The Model: Below is a fold-over diagram of the groundwater model. Fold the diagram to make a 90° angle on the fold line. The top portion of the diagram represents the view looking down at the land. The bottom portion represents the cross-section view that you see when you look at your model from the side. Draw and label your fold-over diagram with as much information from your groundwater model as you can.

Fold line

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2. Where Are the Bottoms of the Wells?Observe as your teacher pours blue-tinted water into the model and then pumps first from Well A and then from Well B. Based on your observation, decide where you think the bottom of each well is and why.

Draw how deep you think the well tubes are for Well A and Well B in your drawing of the model on page 1.

Explain your reasoning for your ideas about how deep the wells are.

In the real world, what factors besides pumping from a well do you think could impact the level of water in the ground?

How do you think the level of the groundwater would change in the spring? In the summer? Why?

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3. Explore With A Model Your teacher will give each group a groundwater model to work with. Explore with your model by gently pumping and/or adding water as you’d like. As you explore, write down your ideas about the questions below.

Does the water seem to flow differently through different materials? Explain any patterns you see.

In the real world, what do you think determines which direction groundwater will move underground?

Write down all the ideas you can come up with about what causes water to move the way it does in the model and underground.

4. Wrap UpWhen you are done exploring with your model and responding to the questions above, please do the following:

a. Pump water out of your model until the level of the water is below the bottom of the lake. Once you have done this, your teacher will collect your model.

b. Carefully empty the storage tank into the sink.c. Clean up your workstation.

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Activity 3: Application Assessment: Where Would You Drill A Well?Summary of ActivityGiven a map/cross-section, students are asked to suggest a location for a new well and justify their answer based on the features on the map and cross-section.

Materials Document camera One Where Would you Drill a Well Handout for each students

Activity Procedures1. Note: You may choose to send this assessment home as homework to collect, then conduct the

class discussion after you have reviewed students’ sheets.Question: Establish a Question2. Show students the handout and model how to use the diagram. Make sure students understand

the task. The river in particular may be confusing to students. The river is at a lower elevation than the road and house. Thus, river on top looks disconnected from the river in the cross-section portion of the diagram.

Apply: Apply knowledge to new context3. Handout the assessment sheet to each student. Students will work alone on this task

as a homework assignment (or, if time is available, provide time in class for students to work on this assessment in pairs).

4. (Next day) Collect and review students’ responses next day.5. Return handouts to students and have them present their choices and reasons to

the class. If possible, use a document camera so students can show their drawings as they present their ideas. Ask individuals in the class if they agree or disagree with the presenting student’s choice and to provide their reasons (use thumbs up/thumbs down strategy). Without giving the students the “correct” answer, guide the discussion to help the students come to consensus. The best location for a well in this cross section is near the river, below the first confining layer. Here, the aquifer will be recharged by the river. A student could put the well above the first confining layer, but there is less surface area to recharge the aquifer, this aquifer is fairly shallow, and the recharge area is partially covered with a road (Cherry Lane). However, in this activity, it is just as important that students provide reasonable evidence and reasons for their well positions as that they locate the well in the “right” place.

Student PagesSee below.

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PracticesAnalyze & Interpret Data

PracticesConstruct Arguments from Evidence

Communicate Arguments

Evaluate Arguments

Reasoning Tools for Understanding Water Systems

Name:Date:

Where Would You Drill A Well?

You own all of the land in the picture on the back of this sheet. You need to drill a well for water for your house. You do not want to take the water directly from the river because the river water is not a clean as the groundwater.

1. Examine the cross-section diagram below and DECIDE and DRAW IN where you would like to drill your well and how deep you will drill it.

Keep in mind: It costs about $9 per foot to drill a well, so you don’t want to have to spend too much money. But you also want to make sure you have enough water for your how.

2. Explain why you chose to put the well WHERE and HOW DEEP you did.

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Activity 4: Get the Groundwater PictureActivity SummaryStudents use well data to construct a cross-section and then use the cross-section to analyze the groundwater system.Project Wet: Pages 136-143

Prior ActivitiesPrior to doing this activity, students should be familiar with cross-sections and permeability. Activities 1-3 in this sequence would provide these experiences.

Tools for ReasoningTracing PathwaysPart III, Step 5c, page 140: What are water sources for the unconfined aquifer?

1. Label several spots on the cross-section. Have students use the Pathways Tool to trace back to possible sources of water. Encourage them to think about multiple pathways that the water might take.

Where is the water?

#8in medium sand 3”

(150 feet) down

After

#8 in medium sand 4” (200 feet) down

#9 in medium sand 4” (200 feet) down

After

#8 in medium sand 5 “ (250 feet) down

#10 in medium sand 5” (250 feet

down)

After

#8 in sandstone 6”

(300 feet) down

#11 in medium sand 6” (300 feet)

down

Before

#7 in medium sand, 2” (100)

down

# 8 in fine sand 2” (100 feet) down

Before

#6 in fine sand 1” (50 feet) down

#8 in fine sand 1” (50 feet) down

Before

#5 in Wetland at surface

#8 in fine sand at surface

farmland

Gravity pulls the water downward. The water table is lower toward well #16, so the water will likely flow towards this low point in the water table. Once the water reaches the clay layer, which is impermeable, the water will not go any deeper and will flow only towards the cone of depression at well #16.

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Practices Using Models Analyzing

and Interpreting Data


Drivers and Constraints Tools1. Part III, Step 4, page 139: Students are asked to trace a drop of water through their well log

and identify where the water would move fastest, where it would move slowest, and where it would be restricted. Before students can answer this question, they first have to trace the water through their column. Use the Drivers and Constraints Tool to support students in considering the effects of permeability in each layer.

Where does thewater start? Where does the water go? What are the drivers? What are the constraints?

Permeability –Fine sand – permeableMedium sand – more permeableSandstone – permeable but not as permeable as fine sandClay – Impermeable

Farmland at # 8

The water will flow down and stop at the clay layerProcess - Infiltration

Gravity pulls water down

The water will infiltrate at the top of the ground (farmland). Gravity will pull the water down. The water will flow fastest through the medium sand layer because it has the highest permeability. It will flow slowest through the sandstone layer and then stop flowing down at the impermeable clay layer.

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2. Part III, Step 5b, page 140. Ask students what direction the groundwater is moving in the unconfined aquifer. The biggest hint is the decrease in elevation of the impermeable layer, which would allow water in the unconfined aquifer to move down in elevation, similar to how surface water moves downhill. The cone of depression shows that well pumping has altered this general trend in the area to the right of the well (columns 16-21). Use the Drivers and Constraints Tool to support students in considering the drivers that would pull water downward and the constraints (impermeable layer) that would define the pathway.

Where does thewater start? Where does the water go? What are the drivers? What are the constraints?

Permeability –Fine sand – permeableMedium sand – more permeableSandstone – permeable but not as permeable as fine sandClay – Impermeable

Column #3The water will flow towards column 16

Process - Infiltration

Gravity pulls water down

The water will infiltrate at the top of the ground (farmland). Gravity will pull the water down through the sand layer. The coarse sand has the highest permeability. The sandstone has a low permeability and the clay is impermeable. The water will not infiltrate below the clay layer. The sandstone layer dips to the right and the water table dips to the right forming a cone of depression. There may be a well at column 16 that is pulling water out. The water in column 3 will flow along the sandstone and clay layers towards column 16 where it may be pulled out in a well.

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Documents

Agenda for the Day · Web viewDay #3 Groundwater 8:30Loose ends from previous Day 8:45Scientific Practices: Explanations and Argument 9:15Introduction to groundwater Student thinking