The US Environmental Protection Agency’s (EPA) Hazardous Waste Codes are an important part of the proper management of hazardous waste in the country. But before we go into the codes themselves, it is important to know the foundation of those codes. In this case, we need to have a basic understanding of the Resource Conservation and Recovery Act (RCRA), its aims, and the EPA’s role in implementing RCRA regulations.
In 1976, Congress enacted the Resource Conservation and Recovery Act, which is an amendment of the Solid Waste Disposal Act of 1965. It’s the US primary federal law presiding over the disposal of solid and hazardous wastes. The RCRA was made in response to the country’s growing volume of municipal and industrial waste.
The Act is made to
- protect public health and the environment from the hazards of waste disposal
- conserve energy and natural resources
- reduce the volume of generated waste through recycling and source reduction
- make certain that waste management is done in an environmentally sound way
The implementation of the RCRA program is shared between the federal government and the state, with the US Environmental Protection Agency (EPA) providing the fundamental requirements. The state governments then adopt, adapt, modify, and enforce their own regulations based on these EPA requirements.
Types of RCRA Waste Codes
Before going to the actual types of EPA waste codes, we need to differentiate two common kinds of hazardous wastes: characteristic and listed wastes. Characteristic wastes are waste materials that are known, proven, tested, or show one or more of the following traits:
- ignitability – the tendency of the material to spontaneously or easily combust even at ambient temperatures
- reactivity – the tendency of the material to cause a chemical reaction when added to another material or subjected to a certain environment
- corrosivity – the tendency of the material to damage or destroy another substance via a chemical reaction
- toxicity – the tendency of the material to cause injury, organ damage, or death (often by chemical reactions or a molecular-level activity) when ingested by an organism, or when an organism is exposed to the material in sufficient amounts
Listed wastes are common waste materials that are generated from common industrial or manufacturing processes. They could also include waste materials that are generated from specific industries, non-specific sources, or commercial products that have been thrown away. These specific waste materials are specifically pre-catalogued and pre-designated by the government as hazardous materials, thus the term “listed.”
Waste materials that are both hazardous and radioactive are called mixed wastes. Regulations for mixed wastes are shared between the RCRA and the Atomic Energy Act (AEA).
Hazardous wastes are categorized as RCRA (subject to RCRA regulations) or non-RCRA (not subject to RCRA regulations. Non-RCRA wastes are, therefore, subject to the state’s regulations). To help determine if a waste material is RCRA or non-RCRA, check out this guide from the EPA.
The RCRA, through the EPA, pre-designates certain wastes as hazardous and are placed on a list. A hazardous waste material is designated by a letter and further classified by a 3-digit number. If your waste material has these combinations, then it is automatically considered as an RCRA hazardous waste.
Listed Waste Codes
F List Codes
Hazardous waste materials in the F list are often generated from common manufacturing and industrial processes. Since these waste-producing processes can happen in different sectors that take part in different sectors of such industries, F-list wastes are often referred to as waste materials from non-specific sources.
K List Codes
Wastes in the K list are produced from specific sources within specific industries. For a waste material to qualify as K-listed, its characteristics must coincide with one of the 13 main industries in the list. In addition, it should correspond with one of the K-list descriptions in 40 CFR Section 261.32.
P/U List Codes
Wastes belonging to the P and U lists are usually generated from commercial grade formulations. Note that they only become a listed waste when such formulations are disposed of or are subject for disposal. Waste materials assigned with a P-code are acutely hazardous. Those with a U code are noted for their chronic or persistent toxicity.
For a hazardous waste material to be listed in a P or U list, it should satisfy three criteria:
- One of the chemicals in the P or U list should be a component in the waste material
- That chemical component should be unused
- That chemical component must be used in or as a commercial chemical product
According to EPA’s definition for P/U list classification purposes, a commercial chemical product is either a 100% pure, a technical grade, or a sole active ingredient in a chemical formulation.
Characteristic Hazardous Waste Codes
D001 Codes
Hazardous wastes in this list exhibit the Ignitability characteristic. The flash point (the lowest temperature which causes the material to combust) for liquid waste material is below 60 degrees Celsius using the Pensky-Martens Closed-Cup Method. D001 wastes materials also include combustible solids, gases, and oxidizers.
D002 Codes
Hazardous wastes in the D002 list are noted for their Corrosivity. These wastes include aqueous liquids that have a ph of 2 or less (base) or a ph 12.5 or above (acid). It also includes substances—often liquids—that deteriorate steel at a rate of 6.35mm or more per year as per the National Association of Corrosion Engineers.
D003 Codes
Waste materials listed in the D003 list are dangerous because of their Reactivity. They combust, detonate, give off toxic gases, or negatively react when they come in contact with water or other substances. Some are inherently unstable even in normal circumstances.
D004 to D043 Codes
Waste materials belonging to the D004 to D043 list are noted for their Toxicity. They become harmful when absorbed by the body through skin permeation, ingestion, or inhalation. Untreated or improperly disposed toxic wastes cause a lot of concern because they might soak through the soil and penetrate groundwater.
The contaminated groundwater may find its way to the municipal potable water supply. If it does, it can potentially create a public health issue.
The Toxicity Characteristic Leaching Procedure (TCLP) (SW-846 Test Method 1311) determines the level of toxicity of a waste material in the D004 to D043 list.
Mixed Wastes
Mixed wastes materials contain both hazardous and radioactive materials. These wastes generated from nuclear power generators, medical equipment used in nuclear medicine, and the like.
The hazardous component of a mixed waste material is regulated by EPA under RCRA. The radioactive component is overseen by either the Department of Energy (DOE) or the Nuclear Regulatory Commission (NRC). As a general rule when it comes to division of authority, the NRC regulates waste from commercial facilities. DOE provides the policies of waste management in DOE-related facilities such as nuclear plants.
Information about EPA’s regulations on mixed waste can be found in the Final Rule.
Hazardous Waste Codes Differences
As you can see above, the hazardous waste codes differences are vast with the exception of the P/U list. Each kind of hazardous waste material is placed into these lists for proper identification and classification.
With the waste materials being properly identified and classified, state governments as well as industrial, medical, and commercial facilities can determine the right protocols as per RCRA/EPA regulations in handling, treating, collecting, and disposing such waste material.
The actual differences lie in the materials number part of the code. However, a comprehensive list of the kinds of materials and their codes are beyond the scope of this article. Instead, we will provide some examples of coded waste materials.
A complete list of EPA waste codes in each list can be found in 40 CFR section 261.
Examples of F-List Codes
- F001 - halogenated solvents used in degreasing such as trichloroethylene, methylene chloride, chlorinated fluorocarbons, and Tetrachloroethylene
- F007 – used or spent cyanide plating bath solutions from electroplating processes
- F012 – wastewater used from metal heat treating operations
- F025 – spent filters, condensed light ends, and filter aids
- F038 – emulsified sludge (oil, water, or solids) from petroleum refineries
For a complete list of F-List waste materials, click the link above and scroll down to 40 CFR section 261.31.
Examples of K-List Codes
- K002 – waste water treatment sludge resulting from the production and processing of yellow and orange pigments
- K009 – distillation sediments from resulting from ethylene in the production of acetaldehyde
- K031 – by-product salts generated from the production of cacodylic acid
- K044 – waste water treatment sludge from the processing and manufacturing of explosives
- K158 - bag house dusts from the production of carbamoyl oximes
For a complete list of K-List waste materials, click the link above and scroll down to 40 CFR section 261.32.
Examples of P-List Codes
- P002 – acetyl, thiourea, acetamide, or amino thiomethyl
- P011 – arsenic oxide AS205 or arsenic pentoxide
- P024 –benzenamine, 4-chloro, or P-chloroaniline
- P030 – cyanide salts
- P189 - carbosulfan
For a complete list of P-List waste materials, click the link above and scroll down to 40 CFR section 261.33.
Examples of U-List Codes
- U008 – acrylic acid
- U012 – Benzenamine
- U032 – calcium chromate
- U044 - chloroform
- U070 - Benzene
For a complete list of U-List waste materials, click the link above and scroll down to 40 CFR section 261.33.
For characteristic waste, the EPA provides a table only for substances with toxic characteristics. The EPA Hazardous Waste number matches the contaminant that makes the waste material hazardous.
Examples of D004 to D043-List Codes
- D004 – Arsenic (at concentrations of 5 milligrams or more per liter)
- D006 – Cadmium (at concentrations of 1 milligram or more per liter)
- D009 – Mercury (at concentrations of 0.2 milligrams or more per liter)
- D011 – Silver ( at concentrations of 5 milligrams or more per liter)
- D039 - Tetrachloroethylene ( at concentrations of 0.7 milligrams or more per liter)
For a complete list of D004 to D043-List waste materials, click the link above and scroll down to 40 CFR section 261.24.
