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Chemical Waste Disposal


Hazardous Waste Disposal Procedures

EHS coordinates disposal of chemical waste from University operations.  The cost of waste disposal is borne by EHS, rather than the individual department or laboratory, in part to eliminate any hesitation to properly manage chemical wastes. 

The following procedures apply to any chemical substances generated from University operations (including laboratories, administrative units, and physical plant operations) that are classified as hazardous based on the criteria described below.  This procedure does not apply to disposal of radioactive or biohazardous wastes.

In order to responsibly manage chemical waste each employee must be familiar with the following:

Hazardous Waste Characteristics

Properly Packaging Waste Materials

Effective labeling

Waste Collection Protocol

Classification of Waste as Hazardous

Waste is considered hazardous if:

  • It is on either of two lists of specific chemical substances developed by the Federal Environmental Protection Agency (EPA). Most commonly used organic solvents (e.g. acetone, methanol, toluene, xylene, methylene chloride etc.) are included (see list). For further information contact Environmental Health & Safety.
  • It is on a list of nonspecific sources that includes a broad range of spent halogenated and non-halogenated solvents (see list).
  • It is on a list of specific sources that includes primarily industrial processes.
  • It exhibits any of the following characteristics as defined by the EPA (definitions are abbreviated):
    • Ignitable
      • a liquid with a flash point less than 60 degrees Centigrade
      • not a liquid and capable under normal conditions of causing fire through friction, absorption of moisture or spontaneous chemical changes
      • an ignitable compressed gas
      • an oxidizer
    • Corrosive
      • it is aqueous and has a pH less than or equal to 2 or greater than or equal to 12.5
      • It is a liquid and corrodes steel at a rate greater than 0.250 inches per year at 55 degrees Centigrade
    • Reactive
      • it is normally unstable
      • it reacts violently with water
      • it forms potentially explosive mixtures with water
      • it generates toxic gases, vapors or fumes when mixed with water
      • cyanide or sulfide wastes that generate toxic gases, vapors or fumes at pH conditions between 2 and 12.5
      • it is capable of detonation or explosive decomposition if subjected to strong initiation or under standard temperature and pressure
      • it is classified as a Department of Transportation explosive
    • Toxicity Characteristic
      • if an extract of the waste is found to contain certain metals, pesticides or selected organics above specified levels (see list).
      • if it is otherwise capable of causing environmental or health damage if improperly disposed (this is a judgment you must make based upon your knowledge of the material from the Material Safety Data Sheet or the literature).

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Packaging Chemical Wastes

Place hazardous waste in sealable containers.  Waste disposal cost is based on volume, not weight, therefore, whenever possible, containers should be filled, leaving headspace for expansion of the contents.  Often the original container is perfectly acceptable.

If you routinely generate significant quantities of compatible solvents or other liquids, bulking of waste in five gallon carboys provided by EHS may be practical. Savings to the University from this practice are substantial.  If you are interested, please call EHS at x8-5294.

The container should not react with the waste being stored (e.g. no hydrofluoric acid in glass).  Similar wastes may be mixed if they are compatible (e.g. non-halogenated solvents).

Whenever possible, wastes from incompatible hazard classes should not be mixed (e.g. organic solvents with oxidizers). Certain metals also cause disposal problems when mixed with flammable liquids or other organic liquids (see special wastes).

Containers must be kept closed except during actual transfers. Do not leave a hazardous waste container with a funnel in it. See Storage of Chemical Waste for more information.

Chemical containers that have been triple-rinsed and air-dried in a ventilated area can be placed in the trash or recycled.  If the original contents were highly toxic, the container should be rinsed first with an appropriate solvent and the washings disposed of as hazardous waste. See Disposal of Empty Glass Chemical Containers for more information.

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Labeling of Chemical Waste Containers

Containers containing hazardous waste must be labeled with the words HAZARDOUS WASTE along with the names of the principal chemical constituents and the approximate percentage.

Waste container labels (see below) can be obtained by contacting Environmental Health & Safety at x8-5294. Use of these labels is preferred but not mandatory unless the waste will be placed in storage before disposal. If you choose not to use the standard labels, the container still must be labeled with the words HAZARDOUS WASTE.

Do not list reactants, only products. For example, if a cyanide was used in a reaction but all of the material was oxidized to a cyanate before disposal, do not list cyanide on the label.

Use IUPAC or full chemical names (in English), no abbreviations, symbols, structural diagrams or product trade names.

Labeling should be accurate and legible and should include the name of the generator, the name of the lab group or PI, the department, and an extension where someone who is knowledgeable about that specific waste can be reached on the day of the pickup in case questions arise during packaging for disposal.

Do not place the date on the label until the day the container is placed in the main collection room. Date the container with the current date once it is removed from the lab for the waste pickup.

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Disposal Procedure

Chemical Waste Pickups are generally scheduled for the last Thursday of each month, January through October. There is no pickup in November, the following pickup is the second or third Thursday in December. The current schedule follows:

  • January 29, 2015
  • February 26, 2015
  • March 26, 2015
  • April 30, 2015
  • May 28, 2015
  • June 25, 2015
  • July 30, 2015
  • August 27, 2015
  • September 24, 2015
  • October 29, 2015
  • December 17, 2015

The Waste Paper newsletter serves as a notice for each pickup and  is distributed to Department Safety Managers, Chemical Hygiene Officers and other interested persons approximately one week in advance. If you would like to be added to the distribution, contact Marcia Leach by e-mail or phone (258-5296).

Pickups take place at six Main Campus locations:

  • Lewis Thomas Laboratory loading dock
    • for wastes from Molecular Biology, Genomics, Psychology, and PNI departments the collection room opens the day before the pickup on Wednesdays from 2:00 - 4:00 PM and Thursday from 8:30 - 9:00 AM
    • coordinators: Michael Fredericks (8-1351) and Andrew States (8-1991) for Mol-Bio and Genomics, respectively.
    • The dropoff of waste generated in GeoSciences and EEB labs is handled by Robert Koenigsmark (8-4123) for GeoSciences, Diane Carlino (8-5810) for EEB. Researchers must contact them for arrangements.
  • Jadwin Hall/Frick Chemistry
    • Collection room next to Jadwin Hall loading dock is open the day before the pickup from 9:00AM - 10:00 AM.
    • Other drop-off times can be accommodated as needed, please coordinate with Philip Fairall (x8-3913) to make these arrangements.
  • Cogen Plant - cogen and chilled water plant waste only
  • MacMillan Building - maintenance wastes only
  • Engineering School (room 7)
    • for E-Quad and Bowen
    • collection room open the day before the pickup from 2:00 - 3:00 PM
    • coordinators: Joe Laskow (8-4739), Joe Palmer (8-4706) and Phil Curry (8-4563)
  • 20 Washington Road loading dock
    • for 20 Washington Rd., Hoyt, Green and 185 Nassau.
    • The regular drop-off schedule has been discontinued for the interim.
    • Drop-off of waste will be accommodated on an as-needed basis. Please coordinate with Kyle Angjelo (x8-2711) to make arrangements.

Specific arrangements for getting material to the pickup site are the responsibility of the individual departments. Refer questions of this nature to your Department Safety Manager or Chemical Hygiene Officer. Generally, wastes must be at the pickup site by 9 A.M. the day of the pickup to be included. See Storage of Chemical Waste for more information.

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Special Wastes

Metallic mercury is a recyclable waste. Please refer to the Mercury Disposal procedures for more information.

Ethidium bromide usually does not need to be disposed as hazardous waste.  Electrophoresis gels containing trace amounts of ethidium bromide (less than 0.1%) may be placed in regular laboratory trash.  Gels containing more than 0.1% (usually dark pink or red color) should be placed in the medical waste boxes.  Ethidium bromide solutions may be neutralized and disposed down the drain.  See Ethidium Bromide Disposal for more information.

Used oil is not disposed as part of the hazardous waste program, with the following exceptions:

  • vacuum pump oil
  • cutting oils
  • PCB contaminated oil
  • oil mixed with hazardous waste

Do not label used oil as hazardous waste.  Instead, label the container with the words "Used Oil", not "waste oil", along with the names of any other constituents.  See Used Oil Disposal for more information.

Silica gel, molecular sieves and desiccants are not considered hazardous waste unless they are grossly contaminated.  Contaminated silica gel can be recycled.  See Disposal of Silica Gel, Molecular Sieves and Desiccants for more information.

Uranium and thorium compounds, such as uranyl acetate, uranyl nitrate, uranyl formate, uranium oxide, thorium nitrate and thorium oxide, are considered radioactive waste, rather than chemical waste.  See Disposal of Uranium and Thorium Compounds for more information.

Chemical wastes that are combined with radioisotopes are considered mixed waste.  Contact Steve Elwood at 258-6271  before generating this type of waste.  Mixed waste is difficult to dispose and should be minimized to the extent possible.

Do not bring wastes to the pickup site that are not properly identified.  It is the chemical user's responsibility to identify and properly label all chemical wastes.  The disposal company cannot legally transport or dispose of unidentified/unknown waste. If they are abandoned at the pickup site they remain the responsibility of the department.  See Unknown Chemicals for more information.

Arrangements for chemical analysis of unknowns can be made through EHS. Costs associated with improper management of hazardous waste (e.g. characterization of unknowns, special handling of peroxide forming compounds etc.) are charged back to the generator department.

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