How do I Conduct Hazardous Waste Characterizations?

The Environmental Protection Agency (EPA) regulates hazardous waste under the Resource Conservation and Recovery Act (RCRA). EPA lists specific hazardous waste in three categories. If not specifically listed, waste must be characterized as hazardous by analyzing samples for ignitability, corrosivity, reactivity and toxicity. Once characterized as hazardous waste, EPA mandates special treatment, storage and disposal technologies to prevent hazardous releases that would harm the public and wildlife.

Things You'll Need

• Waste samples
• Laboratory equipment

Show More

Instructions

EPA Listed Hazardous Waste

• 1

  Check the EPA list of hazardous waste to see if the type of waste is already determined to be hazardous. The EPA maintains a list of hazardous waste categorized by similar origins into three groups: common manufacturing and industrial process include cleaning and degreasing wastes; petroleum refining and pesticide manufacturing include waste water treatment and process sludges; and unused commercial and chemical products include discarded pesticides and pharmaceuticals. Wastes are listed by numeric code. If a waste is found on the list, special treatment, storage and disposal requirements are triggered.

• 2

  Test waste for ignitability. Wastes can spontaneously combust under certain conditions. Special tests determine the flash point for solubles, such as waste oil solvents and solids, such as coated metals. The Penskey-Martens closed cup test is conducted in a laboratory, whereby a liquid sample is heated, stirred and intermittently ignited while in a covered cup. When a flash spreads within the cup, the temperature is recorded as the flash point for that waste. As such, the waste can never be treated, stored of disposed of at that flash point temperature. For solid wastes, a 250 mm length sample is ignited at one end. If it propagates for 200 mm within a specified time period then it is considered a hazardous waste and the burn rate must be established (i.e., how long it takes to burn 100 mm) to determine safe handling procedures.

• 3

  Car batteries can leak acids once they are disposed which can corrode landfill liners.

  Test waste sample for corrosivity. Materials with a pH below two or greater than 12.5 can corrode metal containers, such as storage tanks, drums and barrels. Examples include battery acid. EPA requires aqueous and non-aqueous wastes be tested by exposing "SAE Type 1020" steel to liquid wastes and then measure the degree to which the steel is dissolved. Waste that is characterized as corrosive must be stored, transported or disposed of in specially designed containers.

• 4

  Observe waste sample for reactivity (i.e., instability) before handling. Wastes are considered hazardous if they are become explosive or create toxic fumes when exposed to heat, compression or mixed with water. Lithium sulfide batteries are an example of reactive waste and there are no proscribed test methods. However, observations in a safe laboratory setting can provide information on how to handle wastes. For example, if toxic gases, vapors or fumes are generated when a waste sample is exposed to water then wastes should not be stored or transported near water.

• 5

  Test waste samples for toxicity via the Toxicity Characteristic Leaching Procedure (TCLP). TCLP tests the mobility of inorganic and organic compounds through liquid, solids or multi-phasic wastes then determines the presence and concentrations of compounds after mobile transport. The test simulates the transport of compounds through a landfill. The laboratory analysis accounts for dilution factors and provides a numeric value for toxicity. The value is compared with regulatory levels. If in excess of safe levels, toxic waste must be disposed into specially designed landfills that will prevent toxic releases into the environment.