5.7 Applying the Waste Flow Diagram

Summary

This module teaches how to use the Waste Flow Diagram to quantify plastic leakage from waste management systems into the environment. It covers the necessary tools, explains the leakage and fate decision trees, and provides examples of assessing disposal sites. The video demonstrates calculating leakage amounts and determining the final fates of leaked plastics, encouraging viewers to apply these methods in their own cities.

Takeaways

• 📊 The Waste Flow Diagram is a tool for quantifying plastic leakages from municipal solid waste management systems into the environment.
• 🌐 It helps to determine the final fates of the leaked plastic, such as where it ends up in the environment.
• 📝 Three key components are needed for assessment: leakage decision tree, fate decision tree, and on-site observations.
• 💧 Water-driven leakage and windblown leakage are two types of plastic leakage from disposal sites.
• 🌪️ Windblown leakage has five influencers, while water-driven leakage has only one.
• 🏞️ Environmental hazards, like flooding or landslides, can significantly impact the amount of plastic leakage.
• 🌬️ Exposure to weather, such as strong winds, is a key factor in windblown litter.
• 🗑️ Waste handling practices at the point of discharge can greatly affect the potential for plastic leakage.
• 🌿 The frequency and effectiveness of waste coverage can influence how much plastic is exposed to the elements.
• 🔥 Burning of waste can reduce the amount of plastic available to be windblown, but it is not considered a fate for involuntary leakages.
• 🏗️ The presence and effectiveness of fencing can help contain windblown plastics.
• 📈 The Waste Flow Diagram uses a formula to calculate the total daily leakage of plastic from a disposal site.
• 🌍 Leaked plastic is assumed to end up in one of four fates: retained on land, burnt, cleaned from storm drains, or retained in water systems.
• 📚 The module provides instructions for applying the Waste Flow Diagram tool and recommends further reading for in-depth knowledge.

Q & A

What is the purpose of the Waste Flow Diagram tool?

The Waste Flow Diagram tool is used for a rapid and observation-based assessment to quantify plastic leakages from a municipal solid waste management system into the environment.

What are the three sets of ingredients needed for the assessment using the Waste Flow Diagram?

The three sets of ingredients needed are the leakage decision tree and description tables to estimate the amount, the fate decision tree and description tables to determine the fates, and conducting observations and compiling a good understanding of the situation at the disposal site.

How many leakage influencers are there for disposal sites in the Waste Flow Diagram?

There are six leakage influencers for disposal sites in the Waste Flow Diagram.

What are the two types of plastic leakages caused by disposal sites?

The two types of plastic leakages caused by disposal sites are water-driven leakage and windblown leakage.

How is the total leakage calculated for disposal sites?

The total leakage for disposal sites is calculated as the sum of water-driven leakage and windblown leakage, as shown in the formula provided in the script.

What does the environmental hazards influencer assess in the context of plastic leakage?

The environmental hazards influencer assesses the frequency and impact of flooding events or landslides, which can carry disposed plastics from the site.

What is the role of the exposure to weather influencer in determining windblown litter?

The exposure to weather influencer assesses the frequency of strong winds on the site, which is crucial in calculating the total windblown litter.

How does waste handling at the point of discharge affect the leakage potential?

Waste handling at the point of discharge affects the leakage potential by considering aspects such as the presence of a designated discharge zone, waste pickers' activity, waste compaction or management, and waste exposure to the elements.

What does the coverage influencer look at in terms of plastic leakage?

The coverage influencer looks at the frequency and effectiveness of coverage of the disposed waste, which impacts the potential for windblown leakage.

How does the presence of burning impact the leakage potential?

Although burning is undesirable and hazardous, it can reduce the amounts of plastics prone to be windblown by combusting them, thus affecting the leakage potential.

What is the significance of fencing in determining the fate of leaked plastics?

Fencing can capture a significant portion of flying plastics, thus reducing the amount of leakage. Its existence and effectiveness are observed to determine the leakage potential.

How is the distribution of plastic leakage fates determined using the Waste Flow Diagram?

The distribution of plastic leakage fates is determined by using the fate decision tree and description tables, which consider factors such as the proximity of water bodies, the presence of vegetation, and the frequency of cleaning activities.

What are the four fates that leaked plastic can end up in according to the Waste Flow Diagram?

Leaked plastic can end up retained on land, burnt, cleaned from storm drains, or retained in water systems.

Outlines

00:00

📊 Introduction to Waste Flow Diagram

This paragraph introduces the Waste Flow Diagram tool, which is used for a rapid assessment to quantify plastic leakages from municipal solid waste management systems into the environment. The module aims to teach how to quantify plastic leakages and determine their final fates by evaluating a disposal site. It outlines the necessary components for the assessment: leakage and fate decision trees with description tables for estimation, and the importance of observations for understanding the situation at the disposal site. The paragraph also explains the concept of leakage influencers and how they are used to calculate the total leakage, distinguishing between water-driven and windblown leakages. Examples from Sierra Leone and Senegal are provided to illustrate the application of the tool.

05:04

🌪️ Assessing Windblown Litter Influencers

This section delves into the five wind-related leakage influencers that contribute to the calculation of total windblown litter. It discusses how to assess exposure to weather, waste handling at the point of discharge, coverage frequency and effectiveness, presence of burning, and the existence and effectiveness of fencing. Each influencer has different potential leakage levels, and the paragraph provides examples from various sites to illustrate how these levels are determined. The paragraph concludes with an example of a fictitious disposal site, explaining how to calculate the daily plastic leakage using the Waste Flow Diagram and the relevant influencers assessed.

10:07

🌍 Determining the Fate of Leaked Plastic

The final paragraph explains how to determine the fate of the leaked plastic using the Waste Flow Diagram. It outlines the classification of leakage flows based on the area of occurrence and whether the leakage was voluntary or involuntary. The paragraph uses a disposal site as an example to explain how to assign a point source and involuntary leakage type. It also introduces the concept of fate decision trees and how they are used to determine the distribution of the fates, such as land, drains, and water bodies. The paragraph concludes with an example of how observations around a fictitious dumpsite are used to calculate the percentage of leaked plastic that remains on land, goes into storm drains, or towards water systems.

Keywords

💡Waste Flow Diagram

The Waste Flow Diagram is a tool designed to assess and quantify plastic leakages from municipal solid waste management systems into the environment. It helps determine the amount of plastic escaping disposal sites and evaluates where this leaked plastic ends up. The video uses the diagram to guide viewers through calculating plastic leakage in a disposal site and understanding the impact of various factors influencing leakage.

💡Plastic Leakage

Plastic leakage refers to the escape of plastic waste from municipal waste management systems into the environment, either through wind or water. This concept is central to the video as the tool is used to calculate how much plastic leaks from a given site, such as a landfill, into surrounding areas like water bodies or land.

💡Leakage Influencers

Leakage influencers are specific factors that impact the potential for plastic to escape from a disposal site. These include environmental hazards like flooding, exposure to weather, waste handling at the discharge point, coverage of waste, burning, and fencing. Each of these influencers has different levels of potential leakage, affecting the overall amount of plastic that escapes into the environment.

💡Environmental Hazards

Environmental hazards are natural events such as flooding or landslides that can carry plastic waste from disposal sites into the environment. The video discusses how frequent or large-scale events at a disposal site can result in higher plastic leakage, with specific examples from Sierra Leone and Senegal where flooding or river flow exacerbates plastic leakage.

💡Wind-driven Leakage

Wind-driven leakage occurs when plastic waste is blown out of disposal sites due to strong winds. The video describes how this type of leakage is influenced by factors like exposure to weather, waste handling, coverage, and fencing, and provides examples of how different sites manage or fail to manage windblown litter.

💡Fate Decision Tree

The fate decision tree is a tool used to determine where leaked plastic waste will ultimately end up. It classifies plastic leakage into categories such as retained on land, burnt, cleaned from storm drains, or retained in water systems. The video uses a fate decision tree to show how plastic from a disposal site might be distributed across different environmental fates based on ground observations and specific calculations.

💡Point Source Leakage

Point source leakage refers to plastic leakage that occurs from a single, identifiable location, such as a disposal site. The video explains that this type of leakage is typically involuntary, caused by forces like wind or water, and contrasts it with diffuse leakage, which occurs over many locations. Point source leakage is important for calculating the fate of plastic waste.

💡Voluntary vs. Involuntary Leakage

Voluntary leakage is plastic waste that is deliberately dumped by residents or other actors, whereas involuntary leakage is caused by natural forces such as wind or water. The video focuses on involuntary leakage from disposal sites, showing how natural forces can lead to significant plastic waste being carried away into water bodies or retained on land.

💡Disposal Site

A disposal site is a location where municipal solid waste, including plastic, is deposited. The video examines how plastic leaks from these sites due to various factors such as environmental hazards, wind exposure, and waste handling. Examples from countries like Sierra Leone and Morocco are provided to show different management practices and their influence on leakage.

💡Coverage

Coverage refers to how often and effectively waste is covered at disposal sites to prevent plastic leakage. Sites where waste is covered daily have a lower leakage potential compared to sites where waste is rarely covered, as shown in the video. Coverage is one of the key factors in reducing both windblown and water-driven leakage of plastic waste.

Highlights

Introduction to the Waste Flow Diagram tool for quantifying plastic leakages from waste management systems.

Overview of the three sets of ingredients needed for the assessment: leakage decision tree, fate decision tree, and observation compilation.

Explanation of how to apply the tool to evaluate a disposal site for plastic leakages.

Description of the leakage decision tree for disposal sites, including six leakage influencers.

Differentiation between water-driven and windblown plastic leakage types.

Formula for calculating total leakage by combining water and wind factors.

Importance of user observation in assessing potential leakage levels for each influencer.

Details on environmental hazards as a leakage influencer, including flooding and landslide impacts.

Real-world examples of how to assess environmental hazards in disposal sites.

Introduction to wind-related leakage influencers and their impact on total windblown litter.

Assessment of exposure to weather as a leakage influencer.

Impact of waste handling at the point of discharge on leakage potential.

Coverage influencer's role in determining the frequency and effectiveness of waste coverage.

Effect of waste burning on leakage potential and its classification as a fate.

Importance of observing the existence and effectiveness of fencing on site.

Example calculation of plastic leakage using the Waste Flow Diagram tool for a fictitious disposal site.

Explanation of how to determine the fate of leaked plastic waste.

Classification of leakage flows based on point source and diffused leakage.

Description of the point source involuntary fate decision tree for disposal sites.

Calculation of the distribution of fates for leaked plastic waste based on observations.

Presentation of results in a plastic flow diagram.

Encouragement to apply the tool in one's own city and reference to the user manual for instructions.

Recommendation of additional resources for in-depth knowledge and assessment tools.

Transcripts

Welcome to this module on applying the Waste Flow Diagram.

In the introductory Module, we explained the basics of the Waste Flow Diagram tool,

a rapid and observation-based assessment to quantify plastic leakages from a municipal solid

waste management system into the environment.

After watching this module, you will be able to

quantify plastic leakages, as well as to determine their final fates.

For that, we will see how to apply the tool in order to evaluate a disposal site.

These are the three sets of ingredients you need for such assessment.

The leakage decision tree and description tables to estimate the amount.

The fate decision tree and description tables to determine the fates.

And to conduct observations and compile a good understanding of the situation at the disposal site.

So, let's start quantifying the leakages.

Here we see the leakage decision tree for disposal sites.

It combines 6 leakage influencers. For every influencer, we can see the

different leakage potential levels and their corresponding leakage factors.

For the case of disposal sites, you will notice that there are two separate

plastic leakage types. One caused by water, and the other one caused by wind.

The total leakage is the sum of both as shown in the formula below.

You will also notice that the water-driven leakage only has one leakage influencer,

whereas the windblown leakage has five.

The user of this tool should assess through observations

the level of potential leakage of each of these leakage influencers.

Let's have a look at them one by one.

The first one, environmental hazards, looks at the frequency and impact of

flooding events or landslides, which can carry disposed plastics from the site.

This influencer has five possible leakage potential levels, which are described in this table.

Let's see now some real examples.

This disposal site from Sierra Leone is crossed by a river, which goes directly into the sea.

It is clear that it washes out all the waste that ends up in its basin.

However, compared to the total site of the landfill,

we can say that the site is located in an area where regular

flooding or landslides impact small parts of the site.

From the descriptions given in the table, it would fit best with the medium level.

In this second example from Senegal however, we see that the disposal site is

located in an area prone to occasional flooding or landslides, impacting large

parts of the site. For this case, therefore, we would choose the high level.

Let's move now to the wind-related five leakage influencers.

These are combined to calculate the total windblown litter.

Let's start with exposure to weather.

This influencer assesses the frequency of strong winds on the site.

This information can be obtained by interviewing the site managers,

or checking weather records.

This influencer has three leakage potential levels as shown in the table; high, medium, and low.

If a disposal site is regularly exposed

to heavy and persistent winds like these ones, the user should opt for the high level.

The third influencer on the list is waste handling at the point of discharge.

This influencer has four potential levels and consists of several aspects.

In this site from Sierra Leone, where there is no designated discharge zone,

waste pickers are active on all the site. There is no compaction or management of waste,

and waste is piled above ground with full exposure to wind, rain, and surface runoff.

The leakage potential will be very high.

In contrast, in this other site from Morocco, where waste is discharged in

designated zones, waste pickers are not allowed on-site,

and there is compaction or management of waste.

The leakage potential is low.

The next leakage influencer is coverage. This influencer looks at the frequency

and effectiveness of coverage of the disposed waste.

It has four leakage potential levels.

If waste is typically covered daily, like in this example from Brazil,

then the leakage potential is low.

However, if waste is not covered or covered less than once per month,

like in this site from Bolivia, then the leakage potential is very high.

Then, we assess the presence of burning.

In spite of being a very undesirable and hazardous occurrence,

burning can also act as a trap and reduce the amounts of plastics that

are prone to be windblown by combusting them.

It also has four leakage potential levels.

Disposal sites like this one from Senegal, where waste burning

is widespread and prevalent, will have a low leakage potential.

Finally, the existence and effectiveness of fencing on site should be observed.

This influencer also consists of four potential levels.

If a fence surrounds the entire perimeter and it is maintained, like in this site from

Brazil, it can capture a big portion ofthe flying plastics.

Thank you, Imanol.

Now let's work through an example together.

Let's assume a fictitious disposal site, located in a city around 3 million people.

The site receives 450 tons of municipal solid waste per day,

10 percent of which is plastic, therefore 45 tons of plastic waste per day in total.

Assume as well the influencers relevant to the disposal site

were assessed at the level shown here.

Notice that our site has no water-driven leakage.

The Waste Flow Diagram then combines all corresponding leakage factors,

following the formula given under the decision tree.

On the level selected, the Waste Flow Diagram calculates there will be 23

kilograms of plastic leakage per day, namely plastic escaping from the

disposal site into the surrounding environment.

This represents around 0.05 percent of the incoming

45 tons of plastic waste deposited per day.

Once you have calculated the leakage amount, we can proceed to determine

where this leaked waste will end up.

I hand over to Dr. Josh Cotton who will

guide us through the allocation of these fates.

Thank you.

Leak plastic is assumed to end up in one of the following four fates;

retained on land, burnt, clean from storm drains, or retained in water systems.

The Waste Flow Diagram classifies the leakage flows originating from the stages of the solid

waste management system, according to two criteria.

Firstly, the assess of the area over which the leakage occurred.

If this was from one location, it's known as a point source leakage.

Whereas if it occurred at many different locations is known as a diffused leakage.

Secondly, it assesses whether the leakage was a voluntary act,

such as dumping by residents, or if it was an involuntary act,

such as being blown away by the wind.

Let's consider a disposal site again.

Here the leakage occurs from a set location,

and is leaked due to either wind or rain.

It is therefore assigned a point source; involuntary leakage type.

In a similar manner to the Waste Flow Diagram categories,

each of the leakages are shown in this table. Each category has its own

specific fate decision tree to determine where the plastic leakage ends up.

For example, here is the point source involuntary fate decision tree

that applies to our disposal site. You will notice, we have 3 fates;

land, drains, and water bodies.

For involuntary leakages, like this one, burning is not

considered as a fate. This is because the plastic

is being leaked by natural forces, such as wind or rain, and not by humans.

Therefore, this leaked plastic waste cannot be burnt.

You can see each of the fates in our decision tree

has several options with accompanying fate factors, from none to very high.

Description tables in the user manual outlines the

different requirements for choosing each fate potential.

Here we see the descriptions for the fate land.

Similar to how we did for the leakage influencers, the user

should conduct local ground-based observations to decide which

descriptions in the tables best matches with what they're observing in each location.

As plastic is carried away by water bodies, and therefore may not be observed,

we note the proximity of water bodies within the area instead.

The chosen fate potentials are then combined in the equations

at the bottom of the decision tree to determine the distribution of the fates.

Now let's look at an example together.

Consider we did observations around a fictitious dumpsite.

From our previous leakage assessment, we determined

23 kilograms a day is expected to leak from the dumpsite.

We then notice observations, there were some small areas with large

amounts of waste trapped in the vegetation, and retained on land around the site.

We also observed, only minimal cleaning of the storm drains occurred in

the area, and a number of water systems were in close proximity.

Matching these observations with the description tables, we therefore decided

on the following fate potentials. Using the equations, at the bottom of the decision tree, the

Waste Flow Diagram calculates of the 23 kilograms a day leaked, 62 percent remains on

land, another 15 percent goes into storm drains and is later removed by cleaning, and the

remaining 23 percent goes towards systems.

So we have seen how to calculate plastic leakage

and its fate from a disposal site.

A similar approach can be followed with all the stages

of the solid waste management system in order to get the

total leaked amount into the environment.

The results are then presented in a plastic flow diagram, as the one shown here.

In this module is shown how to apply the Waste Flow Diagram tool

in the example of a disposal site. We saw how to calculate the amount

of plastic leaked into the environment, as well as how to

determine where in the environment it ends up.

So go and try it out yourself in your city, and tell us how it went.

Follow the instructions given in the user manual.

For more in-depth knowledge on the topic, we recommend the following key literature.

For a more in-depth assessment, other tools are available

such as the International Solid Waste Association Plastic Pollution Calculator.

Thank you for watching.