AP Environmental Science

## Learning Outcomes

- Understand what **illegal dumping** and **open dumping** mean and how they differ from legal disposal
- Explain how illegal disposal causes soil, groundwater, and surface water contamination
- Identify why dumped waste can increase disease vectors, fire risk, and air pollution
- Distinguish unmanaged dumps from **sanitary landfills** using engineering controls and monitoring
- Apply examples such as tires, e-waste, household hazardous waste, and construction debris
- Recall key U.S. laws linked to illegal disposal, especially **RCRA (1976)** and **CERCLA (1980)**
- Use cause-and-effect chains in AP Environmental Science free-response answers

## AP Environmental Science Syllabus

For the AP Environmental Science, you are expected to understand illegal disposal problems within solid waste disposal, with a focus on the following syllabus points:

- Know that **illegal dumping** is disposal of waste in unauthorized locations rather than approved facilities
- Identify the difference between **open dumping** and disposal in a **sanitary landfill**
- Explain how **leachate** forms and how it can contaminate soil, groundwater, and surface water
- Understand how dumped waste can attract **disease vectors** such as rats, flies, and mosquitoes
- Know that decomposing organic waste can release **methane**, creating climate and fire hazards
- Identify common high-risk illegally dumped wastes, including tires, e-waste, household hazardous waste, medical waste, and construction debris
- Understand the role of **RCRA Subtitle D**, including the prohibition on open dumping and standards for municipal solid waste landfills
- Recognise that illegal disposal can create both environmental and human health effects, as well as social and economic costs

## Test Your Knowledge

_Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, look more closely at that area during your revision._

1. What is the difference between illegal dumping and a sanitary landfill?
2. How does rainwater turn dumped waste into a water pollution problem?
3. Why are discarded tires a particularly important example in AP Environmental Science?
4. Name two ways illegal disposal can harm human health.
5. Which federal law prohibits open dumping of nonhazardous solid waste?

## Introduction

Illegal disposal problems matter in AP Environmental Science because they connect land pollution, water pollution, air pollution, public health, and environmental justice in one topic. This is not just about ugly piles of trash. When waste is dumped outside approved facilities, it bypasses the controls that are supposed to prevent contamination, fire, and exposure.

In exam questions, illegal disposal is often tested through pathways of harm. You may need to explain how waste left on land can lead to groundwater pollution, stormwater blockage, disease risk, or toxic smoke. The key skill is tracing the sequence clearly from the dumped material to the final environmental effect.

> **Key Term: illegal dumping**
> Disposal of waste in unauthorized or unpermitted locations rather than at approved waste-management facilities.

### Illegal dumping, open dumping, and why the distinction matters

Illegal dumping is the act of putting waste where it is not allowed: roadside ditches, vacant lots, forests, wetlands, riverbanks, abandoned properties, or private land. It is usually deliberate and often involves more waste than ordinary littering.

Open dumping is closely related, but the emphasis is slightly different. It refers to waste disposal practices or sites that do not meet required environmental standards. A place can count as an open dump because it lacks safeguards against water pollution, disease vectors, fires, or air pollution.

> **Key Term: open dumping**
> Disposal of solid waste in a way that does not meet required environmental protection standards; under U.S. law, open dumping is prohibited.

This distinction matters because AP questions may ask you to compare disposal methods. If the question focuses on the action of dumping in an unapproved place, think illegal dumping. If it focuses on the lack of controls and standards, think open dumping.

By contrast, a legal landfill is not just a hole filled with trash. A sanitary landfill is an engineered system designed to isolate waste from the surrounding environment.

> **Key Term: sanitary landfill**
> An engineered waste disposal site that uses controls such as liners, leachate collection, daily cover, gas monitoring, and groundwater monitoring to reduce environmental harm.

A sanitary landfill reduces harm in several ways:

- **Composite liners** help separate waste from soil and groundwater
- **Leachate collection systems** remove contaminated liquid for treatment
- **Daily cover** reduces exposure of waste to wind, rain, insects, and scavengers
- **Methane monitoring and gas controls** reduce explosion risk
- **Groundwater monitoring** checks whether pollutants are escaping

Illegal dumps have none of these protections. That is the main contrast you should make in an exam response.

> **Test Tip:** If a question asks you to compare illegal dumping with landfill disposal, do not just say that one is “bad” and one is “better.” Name the controls in a sanitary landfill and explain which harm each control reduces.

### How illegal disposal causes pollution

The main reason illegal disposal is dangerous is exposure. Waste in an unmanaged pile is exposed to rain, runoff, air, sunlight, animals, and people. That exposure creates several routes by which pollutants spread.

One of the most important is leachate formation.

> **Key Term: leachate**
> Contaminated liquid formed when water moves through waste and dissolves or carries pollutants.

Here is the basic chain:

1. Rain falls on dumped waste
2. Water passes through the waste pile
3. The water dissolves chemicals or picks up particles
4. The contaminated liquid moves into soil, groundwater, or nearby surface water

This can affect both terrestrial and aquatic systems. If waste is dumped on permeable ground, pollutants may infiltrate downward and contaminate groundwater. If the dump is near a stream, ditch, or storm drain, runoff can carry contaminants straight into surface water.

This is why illegal disposal belongs in Unit 8, not only in a “trash” sense but also in a pollution sense. A terrestrial dumping site can become an aquatic pollution source very quickly.

Common pollutants vary by waste type:

- **Household hazardous waste** may release solvents, oils, pesticides, or corrosive chemicals
- **E-waste** may release heavy metals such as lead, mercury, and cadmium
- **Construction and demolition debris** can increase sediment loads and smother habitats
- **Medical waste** can introduce pathogens or sharps injuries
- **Organic waste** can raise decomposition rates and create odor and methane problems

Illegal dumping also blocks drainage channels. This point is easy to miss. If dumped debris clogs storm drains or ditches, water backs up during heavy rain. That can increase flooding, erosion, sedimentation, and habitat damage.

So there are at least three separate water-related harms:

- pollutant leaching into groundwater
- pollutant runoff into streams or wetlands
- physical blockage of drainage that worsens flooding

Students often mention only one. Stronger answers separate them.

Illegal waste can also be burned, either deliberately to reduce volume or accidentally when flammable material ignites. Open burning is not the same as controlled waste-to-energy incineration. Controlled incinerators operate at designed temperatures and under regulations. Open burning releases pollutants without those safeguards.

Possible products of open burning include:

- particulate matter
- toxic smoke
- volatile organic compounds
- sometimes dioxins, especially when mixed or chlorinated wastes burn

This creates a link between land pollution and air pollution.

### High-risk examples: tires, e-waste, hazardous waste, and debris

AP Environmental Science often rewards specific examples. Illegal disposal becomes easier to explain when tied to common dumped materials.

Discarded tires are one of the best examples. They create several different hazards at once. First, they trap rainwater, which makes them excellent mosquito breeding sites. That means a solid waste problem becomes a vector-borne disease problem.

> **Key Term: disease vector**
> An organism, such as a mosquito, rat, or fly, that carries or spreads disease-causing agents.

Second, tires are a major fire hazard. Tire fires are difficult to extinguish and may burn for long periods. While burning, they can release dense smoke, particulates, and toxic compounds. Third, the oily residues left behind can contaminate soil and water.

Tires are therefore a strong AP example because one material links:

- public health risk from mosquitoes
- air pollution from fire
- soil and water contamination from residues

E-waste is another high-yield example. Electronics may contain lead, mercury, cadmium, and other hazardous substances. When dumped illegally, broken apart, or burned, they can contaminate dust, soil, runoff, and groundwater. These substances may also pose neurological or kidney risks to humans.

Household hazardous waste includes paints, pesticides, cleaners, oils, batteries, and solvents. These wastes are especially dangerous when students assume that “household” means harmless. In fact, they can be toxic, ignitable, corrosive, or reactive. If dumped with ordinary trash in an open site, they can contaminate the environment directly.

Medical waste presents a different pattern of harm. Sharps can injure people. Infectious materials can increase disease risk. This is a good example when a question asks for a direct human-health impact rather than a broad environmental effect.

Construction and demolition debris often seems less toxic than electronics or chemicals, but it still causes major problems. Large debris piles can smother vegetation, increase sediment runoff, obstruct drainage, and damage habitats physically. In AP responses, this is useful when you need a terrestrial habitat example rather than a toxicology example.

> **Test Tip:** For FRQs, pair each waste example with its pathway of harm. Do not just list “tires, e-waste, and medical waste.” Explain what each one does: tires breed mosquitoes and burn, e-waste releases heavy metals, medical waste causes injuries and infection.

### Laws, prevention, and exam-style application

The main federal framework for nonhazardous solid waste disposal in the United States is the **Resource Conservation and Recovery Act (RCRA) of 1976**. For this topic, the most relevant part is **RCRA Subtitle D**, which regulates nonhazardous solid waste and prohibits open dumping.

> **Key Term: Resource Conservation and Recovery Act (RCRA)**
> A **1976** U.S. law that regulates the management of solid and hazardous waste, including standards for disposal facilities.

Under this framework:

- open dumping is prohibited
- federal criteria are used to identify unacceptable dumping practices
- municipal solid waste landfills must meet national minimum standards

The standards for landfill units include location restrictions, operating criteria, design criteria, groundwater monitoring, corrective action, closure, and post-closure care. The big AP point is simple: legal disposal requires controls; illegal disposal avoids them.

Another relevant law is **CERCLA (1980)**, often called Superfund.

> **Key Term: Extensive Environmental Response, Compensation, and Liability Act (CERCLA)**
> A **1980** U.S. law giving the federal government authority to respond to hazardous substance releases and clean up contaminated sites.

CERCLA becomes especially relevant if illegal disposal leads to serious contamination, especially at abandoned or closed sites needing cleanup.

Prevention usually works best when legal disposal is easier than illegal disposal. Useful strategies include:

- convenient legal drop-off sites
- free or low-cost bulk pickup
- tire, e-waste, or household hazardous waste collection events
- take-back programs
- fencing, lighting, signs, or cameras at common dump sites
- enforcement through fines, cleanup orders, and monitoring
- public education about hazards and reporting

From an AP perspective, connect prevention to source reduction as well. The best solid waste strategy is not merely better dumping control. It is reducing the amount of waste generated in the first place, followed by reuse, recycling, and composting before disposal.

Illegal disposal also has an environmental justice dimension. Repeated dumping often affects low-income or politically weaker communities more heavily. That means the burden of pollution, cleanup costs, health risk, and lower property values is unevenly distributed.

In a strong exam answer, you can distinguish:

- **environmental effects**: habitat damage, runoff, leachate, air pollution
- **human health effects**: toxic exposure, asthma risk, mosquito-borne disease, injury
- **social and economic effects**: cleanup costs, nuisance, lower property values, unequal community burden

That layered structure shows analysis, not just description.

## Key Point Checklist

_This article has covered the following key knowledge points:_

- **Illegal dumping** is disposal of waste in unauthorized locations
- **Open dumping** refers to disposal that lacks required environmental controls and is prohibited under U.S. law
- A **sanitary landfill** is engineered with liners, leachate collection, cover, gas control, and groundwater monitoring
- **Leachate** forms when water moves through waste and carries pollutants
- Illegal disposal can contaminate soil, groundwater, and surface water
- Dumped debris can block storm drains and increase flooding, erosion, and sedimentation
- Exposed waste can attract **disease vectors** such as rats, flies, and mosquitoes
- Decomposing waste can release **methane**, creating greenhouse and fire hazards
- Tires are a high-yield example because they collect water for mosquitoes and can cause long-lasting fires
- E-waste can release heavy metals such as lead, mercury, and cadmium
- **RCRA (1976)** regulates solid waste disposal and prohibits open dumping under Subtitle D
- **CERCLA (1980)** provides authority for cleanup of hazardous contamination sites

## Key Terms and Concepts

- illegal dumping
- open dumping
- sanitary landfill
- leachate
- disease vector
- Resource Conservation and Recovery Act (RCRA)
- Extensive Environmental Response, Compensation, and Liability Act (CERCLA)


Solid Waste Disposal - Illegal disposal problems