Not all waste are made equal. That is, some are easy to dispose of, while some require special handling and are covered by stricter laws and specific regulations. In this article, we will put our focus on hazardous waste and how to dispose of them properly.
What are hazardous wastes?
As a rule of thumb, hazardous wastes are those which are one, or a combination of the following:
Due to their nature, they can put both people, properties, and the environment at risk. This is why they are treated differently from other wastes produced by households and some businesses, otherwise referred to as waste generators.
Corrosive wastes are either acidic or alkaline and this property allows them to dissolve materials they come in contact with. Human skin is especially vulnerable, while some corrosive wastes are even quick to damage certain metals. A substance is corrosive if it has a pH value of less than or equal to 2, or more than or equal to 12.5.
Ignitable wastes are characterized by their being able to easily be set on fire and sustain the combustion. In liquids, this is if it has a flash point of below 60 Celsius (140 Fahrenheit), while there are also solids and gases that ignite given specific circumstances – open flames, sparks, or even ambient temperature.
Reactive wastes are unstable under normal conditions, and may explode if it comes in contact with water, certain chemicals, or when it reaches a specific temperature. These can also emit toxic gases.
Toxic wastes are harmful and poisonous when inhaled, swallowed, or absorbed via the skin or mucous membranes. These can contaminate the air, soil, or groundwater, negatively affecting the air we breathe, as well as the food and water we eat and drink.
How are hazardous wastes disposed?
Regulations dictate that waste generators are expected to segregate hazardous waste from non-hazardous wastes. Hazardous wastes are then retrieved by specially designated hazardous waste collectors and brought to authorized facilities. Hazardous waste transportation is covered both by EPA regulations and US Department of Transportation regulations.
During transportation, hazardous wastes need to be deposited in portable containers, the most common of which is the 55-gallon drum. Small amounts can be contained in test tubes, buckets, or sealable and specially marked garbage bags. Some chemicals can be transported using their original plastic or glass containers, while larger volumes of hazardous waste are contained and transported through tanker trucks and railroad cars.
Once brought to the appropriate facilities, many hazardous wastes can be safely recycled. Those that cannot, are treated or made less hazardous. When treatment is effective, the resulting wastes can then be disposed of with other non-hazardous wastes in landfills, or incinerated.
However, there are some hazardous wastes that cannot be treated fully or effectively. Instead, these are sealed in specialized containers and buried. Other methods are available. Although the risk of leaks and spills remain, these are mitigated with proper monitoring and other safety protocols.
In order to facilitate the proper recycling, storage, or disposal of hazardous wastes, the US Environmental Protection Agency (EPA) develops and continues to update relevant regulations. These regulations are what governs and certifies Treatment Storage and Disposal Facilities (TSDFs).
Treatment Storage and Disposal Facilities
TSDFs provide one, or combination of the following services:
Treatment is the process of changing the character or composition of hazardous wastes. This is through the use of various means, including incineration or oxidation. Some treatment processes allow further recycling where waste can be recovered and reused. Other treatment processes have the goal of significantly reducing the weight and volume of hazardous waste as in the case of incineration, which reduces tons of waste into several hundred pounds of ash.
Storage is generally understood to be the temporary holding of hazardous wastes until they are treated or disposed of. This is done through containment in specialized tanks, containment buildings, drip pads, surface impoundments, or waste piles.
Disposal is the process of permanently and safely containing hazardous wastes. This is achieved mainly through the use of sanitary landfills, which under existing regulations, must include mechanisms that are designed to protect surface and groundwater contamination.
Tanks are stationary containers constructed of steel, plastic, fiberglass, or concrete. Containment buildings are completely sealed, self-supporting structures (walled, roofed, and floored). Drip pads are engineered structures with a curbed, free-draining base designed to allow the drippage and collection of chemicals, contaminated rain and surface water towards a separate holding tank.
Surface impoundments can either be man-made excavations, diked areas, or natural topographic depressions which accumulate liquid hazardous waste. They are required to have a double liner system, leachate collection and removal systems, and leak detection systems.
Landfills are similar to surface impoundments but are designed for non-liquid hazardous wastes. These are also required to have a double liner system; double leachate collection and removal systems; leak detection systems; run on, run off, and wind dispersal prevention controls; and a final cover.
Waste piles operate in the same way as surface impoundments and landfills, but are for temporary storage or treatment only. They also require the same construction design requirements and safety assurance systems.
There are also land treatment units which employ naturally occurring soil microbes and sunlight to degrade, transform, or render ineffective hazardous components. Constant monitoring ensures that hazardous component levels do not exceed a certain threshold based on background levels.
Hazardous Waste Disposal Regulations
The Resource Conservation and Recovery Act (RCRA) of 1976 is the law which set the general framework for the proper handling of hazardous wastes. Inclusion and exclusion criteria, as well as specific regulations continue to change at the federal and state levels.
The following links should provide up to date information regarding the general framework and how each are to be handled:
Moreover, subject to its mandate, the EPA has created different categories, standards, inclusion and exclusion criteria, and exemptions for different classes of wastes:
Is the material categorized as Academic Laboratory Wastes?
Is the material categorized under Cathode Ray Tubes (CRTs)?
Is the material categorized as Household Hazardous Wastes?
Is the material categorized as Mixed Radiological Wastes?
Is the material categorized as Pharmaceutical Hazardous Wastes?
Is the material categorized as Solvent-Contaminated Wipes?
Is the material categorized as Universal Waste?
Is the material categorized as Used Oil?
Further, state regulatory requirements may or may not be more stringent compared to the federal regulatory requirements. The following provides links to state specific information on hazardous material disposal:
COVID-19 Hazardous Waste Management
In the time of a global pandemic, stringent compliance of hazardous material disposal is more important than ever. One simple misstep in disposing of hazardous wastes during these uncertain times may possibly lead to being infected with COVID-19.
All Regulated Medical Waste (RMW) facilities are equipped and able to properly handle any RMW wastes related to COVID-19. Further, all other hazardous waste including pharmaceutical waste and household hazardous waste known to come in contact with any COVID-19 patient are to be routed to disposal facilities with the proper permits.
If you have any concerns in regards to COVID-19 hazardous waste disposal, you can seek proper advice from your local state agencies.
Common Hazardous Waste Disposal Misconceptions
In order to avoid inconveniencing waste generators, waste transporters, and TSDFs, the EPA clarify the following regarding hazardous material disposal:
Hazardous waste management regulations continue to evolve, and rightfully so. This is because industries, businesses, and households continue to consume a wide array of products which also produce a wide variety of wastes.
It is therefore sensible to keep up to date with relevant regulatio