7.1 Concentrated Solutions of Acids and Bases

Corrosive acids and bases are common wastes generated in laboratories on campus. Corrosivity is the only hazardous waste characteristic that may be treated by a generator onsite without an EPA permit.

Generators of corrosive wastes which have no other hazardous characteristics should neutralize the wastes to a stabilized pH between 5.5 and 9.5. The neutralized non-hazardous waste may then be drain disposed followed with a water flush (20 parts of water).

Procedures for neutralizing acids and bases are described in the following three sections. Note: Neutralization is recommended only for very small volumes of corrosive acids and bases.  You should only perform neutralization of corrosives if you have been trained, you feel confident that you understand the process, you have the proper personal protective equipment, and are comfortable doing it. 

7.2 Organic Solvents

Most spent organic solvents will be classified as an F-Listed or Characteristic hazardous waste.  Laboratories or other areas generating more than 5 gallons of hazardous waste (spent solvents) per month should accumulate the waste in safety cans.  EHS will provide 5 gallon safety cans to generators of solvent hazardous waste on a case-by-case basis.  Users of safety cans must make sure that the words "Hazardous Waste" and other wording describing the solvents in the waste are clearly marked on the safety can as soon as waste begins to be accumulated.  Except when waste is being added to or removed from a safety can containing hazardous waste, its lid needs to be closed at all times.

Do not dispose of organic solvents down the drain. Generators of organic solvents should keep non-halogenated waste solvents separated from halogenated waste solvents to the fullest extent possible. EHS bulks organic solvents into 55 gallon metal drums for fuels blending. It costs approximately twice as much to dispose of a drum of halogenated waste solvents versus a drum of nonhalogenated waste solvents.

Safety cans should only be used for the storage of waste organic solvents. Other wastes are inappropriate for fuels blending, can have a detrimental effect on the integrity of the metal 55 gallons drums used, and represent a serious health and safety issue to EHS staff.

Please do your part to help keep waste disposal costs down by:

• Keeping corrosive wastes separated from organic solvents whenever possible.
• Keeping nonhalogenated organic solvents separated from halogenated organic solvents whenever possible.

Examples of nonhalogenated organic solvents that are acceptable to be collected in safety disposal cans include:

• Acetone
• Acetonitrile
• Ethanol 
• Formaldehyde
• Ether
• Ethyl acetate
• Hexane
• Toluene
• Xylenes

Examples of halogenated organic solvents that are acceptable to be collected in safety disposal cans include:

• Methylene chloride
• Chloroform
• Carbon tetrachloride
• Bromoform
• Mixtures containing both halogenated and nonhalogenated organic solvents 

The following wastes must NOT be collected in safety disposal cans:

• Strong acid or base solutions (a pH between 5.5 and 9.5 is acceptable)
• Aqueous solutions of toxic organic chemicals
• Heavy metals (Lead, Mercury, Silver, Chromium, Barium, etc.)
• Vacuum pump used oil
• Sulfides or inorganic cyanides
• Strong oxidizers or reducers
• Water reactive substances 
• PCB waste 
• Unknowns

Please be sure to include approximate percentages of all waste solvents placed in safety cans. Do not rely on your memory to label solvents, keep a running list of solvents that you add to the safety disposal can.

Hazardous Waste Labels from EHS should be used when collecting hazardous chemical waste in safety cans. When requesting removal using the online form, it is important to note the size of the container(s) to be removed.  For more information on safety disposal cans, please contact EHS at "askEHS".

7.3 Aqueous Solutions of Toxic Chemicals

Aqueous solutions containing heavy metals and/or other RCRA regulated toxic chemicals must be disposed of through the hazardous waste management program. Do not dispose of this type of waste down the drain, dispose of these chemicals through the hazardous waste management program.

7.4 Used Oil

Uncontaminated used oil is not considered hazardous and should be collected and recycled. Do not mix other chemical wastes with used oil. If a hazardous waste, such as flammable solvents or heavy metals, is added to used oil, then the resulting mixture cannot be recycled and must be handled as hazardous waste. Be sure to note any contaminants on the Hazardous Waste Label when disposing of contaminated used oil.

Uncontaminated used oil to be recycled must be labeled with the identifying words "Used Oil”. Cornell’s R5 Group manages the Used Oil Recycling Program.

7.5 Asbestos

Asbestos is a fibrous material that was once widely used in a number of products that can still be found in laboratories and throughout other buildings. Products that can contain asbestos include: electrical equipment insulation (ovens, heating mantles, heating pads, and wires), older vinyl floor tiles and mastic, pipe fittings, pipe insulation, caulking compounds, fireproofing, and transite (cement-like) panels such as those found in and under fume hoods.

Asbestos is a known human carcinogen and must be disposed of properly. The hazard of asbestos is greatest when the asbestos product becomes “friable” – able to be pulverized from finger pressure – and when the asbestos becomes airborne. For older vinyl asbestos tile (VAT), an additional slipping hazard occurs when these tiles “pop” out of the floor.

If you find any of the above items deteriorating and suspect they may contain asbestos, or you are considering disposing of old electrical equipment with insulation, or if vinyl tiles have “popped” out of the floor, then please contact the asbestos coordinator at 607-254-5439 for more information.

7.6 Silica Gel

Silica gel contaminated with solvents, heavy metals, or other toxic chemicals should be accumulated in leak proof containers such as one gallon plastic wide mouth containers or a five gallon bucket. Contact EHS waste management personnel at 607-255-4642 for these supplies.

When labeling Silica gel waste, be sure to list all of the contaminants, including solvents, and the approximate percentages on the Hazardous Waste Label.

7.7 Chemically Contaminated Items / Empty Containers

In general, Chemically Contaminated Items (CCIs) can only be put into the normal trash if they are non-hazardous, non-ignitable, non-reactive, non-carcinogenic, non-mutagenic, non-infectious, non-radioactive, and the contaminant is not highly toxic. Examples include disposable items such as gloves, benchtop coverings, pipets, test tubes, etc.

If you feel that the normal trash is not an appropriate disposal route for your CCIs, then package them in a leak-proof container or plastic bag and label with a Hazardous Waste Label as “Chemically Contaminated Items” and the name and approximate percentage of chemical contaminants.

Chemical containers which have been emptied by all practicable means, i.e., pouring, pumping scraping etc., and there is less than one inch of residue, or no more than 3% of the total weight of the container if it was less than 119 gallons, and the container didn’t previously hold a chemical that would be an acutely toxic waste (P-Listed), the container is considered trash.  This is the definition of a RCRA empty container.

EHS recommends rinsing RCRA empty containers before putting them into the lab trash cans because of potential odor issues.  Labels on containers should be defaced or removed before disposal in a trash can or dumpster.

If the empty container didn’t hold a waste solvent or a P-Listed liquid and is truly “RCRA Empty”, as described in the 3rd paragraph of this section, then letting it air out under a hood would be permissible.  It’s not permitted to allow a hazardous waste to evaporate in lieu of disposal.

You may use soap and water to rinse containers which once held solvents, whether they were non-miscible or not.  Do not use a solvent to rinse an empty container because it generates more waste.  If an empty container requiring disposal is stinky, non-miscible (and not P-Listed) the easiest solution is putting it into a plastic bag and placing it in the dumpster.  Please be aware that some campus facilities, custodial personnel may not be permitted to dispose of questionable chemical containers in the trash.  This may require you to personally bag or box your waste containers and dispose of them in the facility dumpster.

If you have any questions concerning management of chemically contaminated items or containers, please contact EHS at "askEHS".

7.8 Mercury

Metallic mercury is collected and recycled. It should be packaged in a tightly sealed and leak free container such as a bottle or vial with a screw top lid. Place broken mercury thermometers in a leak proof container or a secured plastic bag. When collecting metallic mercury, DO NOT mix with other chemicals or waste if at all possible.

Do not use the past practice of adding sulfur, nitric acid, or water in an attempt to contain vapors. This only results in more hazardous waste being generated and rendering the metallic mercury as non-recyclable. However, the use of commercial ‘Hg Absorb’ powder found in mercury spill kits is acceptable. Commercial mercury spill kits can be found through Cornell’s eShop preferred suppliers.

Mercury is a highly toxic chemical and any mercury spills, including broken thermometers, must be cleaned up and the spill debris disposed through the hazardous waste management program. If you have a spill of mercury outside of the fume hood, leave the room and call 911 to report the spill information.

Never use a regular vacuum cleaner to clean up a mercury spill, this will only cause the mercury to vaporize and disperse into the air. EHS has a special mercury vacuum designed for cleaning up mercury spills and a mercury detection meter to determine if all mercury has been cleaned up from a spill.

For more information on mercury and management of mercury at Cornell, go to the Mercury Thermometer Exchange Program.

7.9 Fluorescent Tubes (Universal Waste Lamps)

Fluorescent bulbs and other hazardous lamps such as mercury vapor, high pressure sodium lamps, high intensity discharge (HID), neon, and metal halide lamps are regulated as Universal Waste Lamps and must be disposed of properly. These items (including "green tip" bulbs) cannot be placed in the normal trash. Broken fluorescent tubes must be handled as hazardous waste. Every attempt should be made to keep these items intact and to prevent breakage.

At Cornell University, the R5 Group manages the pickup and disposal of all Universal Waste Lamps and Batteries. R5 Group is also responsible for managing other recyclable materials such as Used Oil, Scrap Metal, Batteries, Refrigerated Appliances, old Computers, and Electronic Equipment. Contact the R5 Group at 607-254-1666 if you have questions about the disposal requirements and procedures for any of these items. 

7.10 Batteries (Universal Waste Batteries)

There is a program in place to recycle batteries (Alkaline, Ni-Cad, Lithium, Lead-acid, Mercury, and button batteries). There are a number of battery collection containers around campus for Universal Waste Batteries. Contact the Recycling Coordinator at 607-255-1082 If you would like to request a battery collection container for your building/work area, or if a battery collection container is full. 

7.11 Computers and Other Electronic Equipment

There is a program in place to recycle computers and other electronic equipment. There are heavy and precious metals in many components of computers. Old computer equipment cannot be disposed of in the normal trash. If you are planning on disposing of these items, then please contact the Recycling Coordinator at 607-254-1666.

7.12 Aerosol Cans and Propane Cylinders

Aerosol cans and small Propane cylinders can contain flammable, corrosive, and toxic chemicals and propellants. These items can be collected, emptied of their contents, depressurized, and recycled for scrap metal. Aerosol cans and small Propane cylinders are collected during regular hazardous waste pickups.

If you have a large (2 or 4 foot) high-pressure gas cylinder and would like to have it removed, then please contact AIRGAS or EHS at "askEHS" for assistance. 

7.13 Paint, Paint Thinner, Adhesives, and Printshop Chemicals

Paint (oil-based), Paint thinner, Adhesives, and many Printshop chemicals are flammable and regulated as hazardous waste. These items cannot be poured down the drain or left out to evaporate. They must be disposed of through the hazardous waste management program. Latex paint that has solidified completely can be placed in the normal trash. You can speed up the solidification of latex paint by adding sawdust or vermiculite and leaving it out to evaporate.

7.14 Photographic Chemicals

Some photographic chemicals contain heavy metals such as Silver, Chromium, and Selenium that may be above regulatory levels and must be handled as hazardous waste.

Used photographic fixer contains Silver above regulatory levels and cannot be poured down the drain; however, some photographic developers and other chemicals may be disposed of down the drain depending on the chemical constituents.

Cornell University has Silver Reclamation Units at a number of locations on campus to recover silver while minimizing hazardous waste. Negatives from x-ray units, old or expired photographic paper and film, and other photography are collected and shipped offsite for silver recovery. More information on these units can be found on the Silver Reclamation Tipsheet.

7.15 Reactive and Potentially Explosive Chemicals

Reactive chemicals such as strong oxidizers and reducers, and air/water reactive chemicals must be disposed of through the hazardous waste management program. Because of their reactive nature, it is important to minimize the quantity of reactive chemicals in storage. If the integrity of the container appears to be compromised, then dispose of the chemicals as hazardous waste promptly. Never dispose of reactive chemicals, such as Sodium metal, regardless of the quantity, down the drain or in the normal trash. Such practices can result in fires, toxic vapors and gases being released, and injury to people. When disposing of these compounds, please note any special hazards on the Hazardous Waste Label.

Some of these compounds can become unstable and potentially explosive over time due to contamination with air, water, other material, or when the chemical dries out. If you come across any chemical that you suspect could be potentially explosive, do not attempt to move the container as some of these compounds are shock, heat, and friction sensitive. Be sure to let others in the lab or work area know the chemical exists and the potential explosion hazard.  Submit a question using "askEHS".  If you feel that there is an immediate potential hazard, please contact EHS at 607-255-8200 for more assistance.

Explosive Compounds

​Examples of potentially explosive chemicals include:

7.16 Peroxide Forming Chemicals

Many commonly used chemicals, organic solvents in particular, can form shock, heat, and friction sensitive peroxides upon exposure to oxygen through concentration, evaporation, and distillation.

Compounds that are suspected of having very high peroxide levels because of age, unusual viscosity, discoloration, or crystal formation should be considered extremely dangerous. If you discover a container that meets this description, DO NOT attempt to open or move the container. Make other people working in your area aware of the potential explosion hazard and contact EHS immediately at "askEHS".

You will find extensive information related to peroxide forming chemicals, including a list of peroxide formers, and how to test for peroxides in the Laboratory Safety Manual and Chemical Hygiene Plan.

7.17 Unknowns

You must make every effort to provide an accurate description of all chemicals that you dispose of through the hazardous waste management program. Without an accurate description, the chemical cannot be handled or disposed of safely. Waste disposal companies will not accept unknown chemical waste without the generator providing a sample analysis which can be very expensive.

Many unknown chemicals are generated due to a lack of good housekeeping and good laboratory safety practices. ALL containers used to store chemicals must be labeled. Containers in which the labels are degrading or falling off should be given a new label. There are numerous reference materials with methods and procedures that can be used in identifying unknown chemicals.

It is the responsibility of the generator of the waste to field test the material before it is sent in to be analyzed so that the testing lab has as much information on the unknown material as possible. For example, if you know the pH, or the water and solvent solubility of the material, or the history and use of the material is known.

If you need to dispose of an unknown material you must first complete and submit a copy of the Unknown Chemical Waste Characterization Form found in Appendix C of this manual.  A completed form must be submitted for each unknown chemical container.  Please be sure to include the Cornell Hazardous Waste Label number on each completed form.

7.18 Household Hazardous Waste

Cornell University cannot accept household hazardous waste for disposal. However, most local communities and/or counties have programs for collection of household hazardous waste. Typical wastes accepted (not all are listed here) include:

• Adhesives, coatings, and sealers
• Auto fluids and oil filters
• Cleaners and aerosols 
• Concrete and driveway sealants 
• Fluorescent bulbs 
• Household batteries 
• Paints and solvents 
• Pesticides and fertilizers 
• Photographic, pool, and lab chemicals 
• Various electronics, computers, phones, etc. 
• Varnishes, shellacs, and stains

Many of these programs are free of charge but residency for that locality or county is normally required. Please check the following online sites to see if and when a Household Hazardous Waste Program is available for your area.

• NYSDEC
• Cortland  County
• Tompkins County

7.19 Ethidium Bromide

Mutagenic chemicals, such as ethidium bromide, pose a threat to organic life due to their ability to modify an organism’s genetic material that may be passed along to future generations.

Active ethidium bromide wastes may not be disposed of via the sanitary sewer or municipal trash without first being deactivated. Ethidium bromide wastes that do not fluoresce are considered to be inactive and could be acceptable for drain or trash disposal depending on the chemical constituents of the dye. There are a variety of options for disposal depending on the type of waste.