XI(a). Waste Disposal - Chemical Waste


rev 6/2010

A. What Is Hazardous Chemical Waste?

In order to determine proper handling procedures and disposal, a decision must be made regarding whether the chemical waste is hazardous. Federal (EPA 40 CFR 261) and Massachusetts (DEP 310 CMR 30.100) regulations define various categories of hazardous chemical waste. Additionally, the college holds a pretreatment permit from the Town of South Hadley that regulates discharge to the sewer system. A summary of waste typically generated in academic laboratories is included in Appendix A. Regulatory lists for the following waste categories are available at the DEP website referenced below.

  • hazardous chemicals (specific list of chemicals) - U wastes
  • acutely hazardous chemicals - P wastes
  • solvent waste - F wastes
  • characteristic wastes - D wastes:
          - ignitable
          - corrosive
          - reactive
          - toxic (includes metals, pesticides, and various organics)
  • waste oil and PCBs - M wastes

Faculty are responsible for determining whether laboratory waste generated is a hazardous waste. The “Laboratory Hazardous Waste Determination” checklist found in Appendix C can be used to evaluate laboratory waste. Departments will keep the checklist or other documentation for teaching laboratories; faculty will keep documentation for their research laboratories. Faculty will review the determination when changes in the laboratory experiment could change the classification of the waste. The checklist does not apply to evaluation of unused chemicals, or spill clean-up materials. The Chemical Hygiene Officer can assist with evaluation of these materials, as well as laboratory waste.

There are other chemicals that have not been defined as hazardous by EPA or the Massachusetts DEP that should be handled using the procedure for hazardous waste. These include:

  • carcinogens that have not been deactivated (see Section V(i) Select Carcinogens),
  • reproductive toxins, e.g., ethidium bromide, that have not been deactivated (see Section V(j) Reproductive Toxins), and
  • acute toxins (see Section V(h))

Faculty or staff may designate other chemical wastes to be handled as hazardous based on their knowledge of the hazards of the waste.

DEP, 310 CMR 30.100 Identification and Listing of Hazardous Waste

B. Disposal Of Non-Hazardous Chemical Waste

Once a waste determination concludes that waste is not a hazardous waste, it may be disposed of as a non-hazardous waste. Liquid wastes that are non-hazardous and water-soluble may be flushed to the sewer with copious amounts of water. Liquids, which are not water-soluble, must be solidified (absorbed) and disposed of as a solid. Non-hazardous solid waste must be labeled "non-hazardous" and can then be put in the laboratory trash.

C. Hazardous Waste Collection And Lab Accumulation

All hazardous waste must be collected for disposal by an EPA approved method at a licensed facility. Hazardous waste should be collected in each laboratory in screw top containers, which are compatible with the waste. Each container should be labeled with a red and white "Hazardous Waste" label at the time waste is first put into the container. The label must contain:

  • waste components; each chemical present must be identified (no chemical formulas, structures or abbreviations may be used)
  • hazards (e.g., flammable, oxidizer, corrosive, toxic, reactive)

Additional space on the label may be used to list a generic waste name such as “chlorinated solvents”. The "Date Full or Moved to Storage" should be completed when the container is full or, if not full but the waste is no longer being generated, when it is moved to storage. Indelible markers should be used for labeling and abbreviations cannot be used. Containers must be closed except when waste is being added. A poster describing laboratory waste collection requirements is included in Appendix B.

To minimize the hazard of incompatible chemical reactions, wastes should not be mixed in the laboratory. It is also important to separate chlorinated from non-chlorinated solvents whenever possible, as non-chlorinated solvents can be processed for reuse and chlorinated solvents must be incinerated. Waste containers must be kept near the point of generation and all liquid waste must be in secondary containment. The secondary containment must provide for separation of wastes that are incompatible. The amount of waste accumulated in the laboratory at any time should be minimized. Only one bottle of a particular type of waste is allowed in the laboratory.

D. Laboratory Waste Removal

When a waste container is full or the waste will no longer be generated in the laboratory, the waste must be moved to the storage area within 3 days. Check the containers to make sure they are properly closed and that the labels are complete and legible.

Request a pick-up immediately upon filling a container, or ahead of time if you anticipate filling a container in the next day or two. For waste pick-up, contact Lori Smith in Environmental Health & Safety.

E. Waste Storage And Disposal

Upon receipt at the waste storage room, all waste is separated and stored by hazard category. To minimize the potential for releases all waste containers are placed in trays or other secondary containers.

Wastes are shipped off-site using a licensed hazardous waste transporter. All hazardous waste is taken to licensed facilities who treat, recycle, incinerate, or otherwise dispose of the materials using EPA approved methods for the particular waste type.

F. Disposal Of Empty Containers And Sharp Waste

The hazardous waste regulations define an empty container as a container from which all hazardous chemical which can be poured has been removed and no more than one inch of chemical remains.

Most empty containers can be safely and legally disposed of as laboratory trash with the exception of "Acutely Hazardous Waste" containers. Empty containers that contained “P” listed acutely hazardous chemicals, should be handled as hazardous waste. As an alternate, these containers can be triple rinsed with an appropriate solvent, with the solvent disposed of as hazardous waste, the label defaced, and the container discarded in the laboratory trash.

Empty containers should be placed next to (not mixed in with) laboratory trash. Broken glass and other sharp waste, except needles should be placed in cardboard containers designated for that purpose. The custodians will discard these containers in such a manner as to avoid injury. Needles must be collected in plastic needle boxes and sent off-site for incineration as biomedical waste.

G. Disposal Of Unknowns

It is extremely difficult and costly to identify the content and hazards of unlabeled materials. As discussed in Section V(c), it is crucial that maintaining labels be a standard laboratory practice. If you do have unknowns, please contact the Chemical Hygiene Officer immediately upon their discovery.

H. Disposal Of Equipment

All hazardous materials (e.g. mercury switches, PCB capacitors, oil) must be removed from equipment before it is discarded. The faculty member or department is responsible for removal of these materials and management of them as hazardous waste. Electronic equipment should be collected for recycling. Contact the Chemical Hygiene Officer for instructions.

I. Waste Inspection

The Chemical Hygiene Officer inspects the waste storage area and satellite accumulation areas in the labs weekly when waste is present. Deficiencies that could result in a release of waste are corrected immediately; other deficiencies are referred to the responsible faculty member for correction. The Chemical Hygiene Officer then confirms that the correction has been completed.

J. Working Containers

DEP Working Container provisions allow more than one container of a particular waste in the laboratory for immediate use at the bench top. The Working Container must be:

  • emptied into the satellite container in the laboratory at the end of each laboratory period or day, or when full whichever comes first
  • closed except during active use
  • located on an impervious surface and managed to prevent spills
  • labeled as "hazardous waste" with words describing the hazard
  • located at or near the point of generation
  • under the control of faculty or staff responsible for the laboratory


A: Hazardous Waste Identification

B: Hazardous Waste Determination Form

C: Hazardous Waste Collection Poster