Segregation of Waste Chemicals

PURPOSE: To assure safe storage and segregation or waste chemicals

DATE OF ISSUANCE: 2/28/97 

The proper segregation of waste chemicals is essential to promote safe storage of those chemicals as well as to facilitate the economical disposal of the chemicals. The Environmental Protection Agency (EPA) has published a list of potentially incompatible wastes, waste components, and material along with the harmful consequences of mixing those materials together. This list does not include every possible hazardous chemical reaction, but should be used as a guide in packaging and storing these materials. The list indicates the potential consequences of the mixing of a Group A material with a Group B material. These compatibility listings should not be the only information used when packaging or accumulating waste chemicals. Pay close attention to any waste characterization data you receive on material reactivity and compatibility. Material Safety Data Sheets contain a section devoted to chemical reactivity and incompatibility. The following lists of chemicals in Groups A should be kept separate from those chemicals in Groups B:

Group A

Group B

Group 1-A

  • Bases
  • Potential consequences:  Heat generation; violent reaction

Group 1-B

  • Acids

Group 2-A

  • Aluminum
  • Beryllium
  • Calcium
  • Lithium
  • Magnesium
  • Potassium
  • Sodium
  • Zinc powder
  • Other reactive metals and metal hydrides
  • Potential consequences: Fire, Explosion, or generation of flammable hydrogen gas.

Group 2-B

  • Any Acid or Bases

Group 3-A

  • Alcohols
  • Water
  • Potential consequences: Fire, Explosion, or heat generation:
    generation of flammable or toxic gases.
 Group 3-B
  • Any Concentrated Acids or Bases
  • Calcium
  • Lithium
  • Magnesium
  • Sodium
  • Zinc Powder
  • Any Reactive Metals and Metal Hydrides
  • Potassium
  • Sulfonyl chloride
  • Thionyl chloride
  • Phosphorus trichloride
  • Methyl trichloride
  • Methyl trichlorosilane
  • Other water-reactive waste

Group 4-A

  • Alcohols
  • Aldehydes
  • Halogenated hydrocarbons
  • Nitrated hydrocarbons
  • Unsaturated hydrocarbons
  • Other organic compounds and solvents
  • Potential consequences:  Fire, Explosion, or violent reaction.

Group 4-B

  • Any Concentrated Acids or Basses
  • Reactive Metals and Metal Hydrides

Group 5-A

  • Cyanide's and sulfide's
  • Potential consequences:  Generation of toxic hydrogen cyanide or hydrogen sulfide gas.

Group 5-B

  • Any Acids

Group 6-A

  • Chlorates
  • Chlorine
  • Chlorites
  • chromic acid
  • Hypochlorites
  • Nitrates
  • Nitric acid, fuming
  • Perchlorates
  • Permanganates
  • Peroxides
  • Other strong oxidizers
  • Potential consequences:  Fire, Explosion, or violent reaction.

Group 6-B

  • Acetic acid and other organic acids
  • Concentrated mineral acids
  • Reactive Metals and Metal Hydrides
  • Organic Compounds and Solvents
  • Other flammable and combustible chemicals

The following two groups are added to facilitate the economical disposal of the wastes.  They are not necessarily reactive.

Group 7-A

  • Heavy metal Compounds containing arsenic, barium, cadmium, chromium, lead, selenium, silver
  • Polychorlinated biphenyls (PCBs) Dioxins
  • Mercury Containing Compounds

Group 7-B

  • Flammable Liquids

Group 8-A

  • Polychlorinated biphenyls (PCBs)
  • Dioxins
  • Mercury Containing Compounds

Group 8-B

  • All other chemicals and each other