310 CMR 30.561
Examples of Potentially Incompatible Wastes
Manyhazardous wastes, when mixed with other waste or material, can produce effects which
are harmful to human health and the environment, such as (1) heat or pressure, (2) fire or
explosion, (3) violent reaction, (4) toxic dusts; mists, fumes, or gases, or (5) flammable fumes
or gases.
Below are examples of potentially incompatible wastes, waste components, and materials,
along with the harmful consequences which might result from mixing material in one group with
material in another group. The list is intended only as a guide to indicate the need for special
precautions when managing these potentially incompatible waste materials or components.
This list is not intended to be exhaustive. An owner or operator shall, as regulations require,
adequately analyze his wastes so that he can prevent creating uncontrolled substances or
reactions of the type listed below, whether they are listed below or not.
In the lists below, the mixing of a Group A material with a Group B material might have the
potential consequences as noted.
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Group 1-A
Group 1-B
Acetylene sludge
Acid sludge
Alkaline caustic liquids
Acid and water
Alkaline cleaner
Battery acid
Alkaline corrosive liquids
Chemical cleaners
Alkaline corrosive battery fluid
Electrolyte, acid
Caustic wastewater
Etching acid liquid or solvent
Lime sludge and other corrosive
Pickling liquor and other
alkalies
corrosive acids
Lime wastewater
Spent acid
Lime and water
Spent mixed acid
Spent caustic
Spent sulfuric acid
Potential consequences: Heat generation; violent reaction.
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Group 2-A
Group 2-B
Aluminum
Any waste in Group 1-A or 1-B
Beryllium
Calcium
Lithium
Magnesium
Potassium
Sodium
Zinc powder
Other reactive metals and metal
hydrides
Potential consequences: Fire or explosion; generation of flammable hydrogen gas.
Group 3-A
Group 3-B
Alcohols
Any concentrated waste
Water
in Groups 1-A or 1-B
Calcium
Lithium
Metal hydrides
Potassium
SO2Cl2, SOCl2, PCl3, CH3SiCl3
Other water-reactive waste
Potential consequences: Fire, explosion, or heat generation; generation of flammable or toxic
gases.
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Group 4-A
Group 4-B
Alcohols
Concentrated Group 1-A
Aldehydes
or 1-B wastes
Halogenated hydrocarbons
Group 2-A wastes
Nitrated hydrocarbons
Unsaturated hydrocarbons
Other reactive organic compounds
and solvents
Potential consequences: Fire, explosion, or violent reaction.
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Group 5-A
Group 5-B
Spent cyanide and sulfide
Group 1-B wastes
solutions
Potential consequences: Generation of toxic hydrogen cyanide or hydrogen sulfide gas.
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Group 6-A
Group 6-B
Chlorates
Acetic acid and other
Chlorine
organic acids
Chlorites
Concentrated mineral acids
Chromic acid
Group 2-A wastes
Hypochlorites
Group 4-A wastes
Nitrates
Other flammable and
Nitric acid, fuming
combustible wastes
Perchlorates
Permanganates
Peroxides
Other strong oxidizers
Potential consequences: Fire, explosion, or violent reaction.