A. General Source Reduction and Waste Minimization Methods
- Minimize mixing hazardous waste with non-hazardous waste, such as water. Do not dilute hazardous waste. This not only increases the volume necessary for disposal, but may also affect any reusable properties of the waste, such as British Thermal Unit (BTU)/heat value. The only exception is adding water to explosive chemicals to keep them wet.
- Segregate your waste according to waste streams, such as: organic solvent waste (no water), photo fixer waste, aqueous waste with organic solvents, aqueous waste with toxic heavy metals, aqueous acidic waste, aqueous basic waste, metallic mercury waste, lubricating oil, formalin, ethidium bromide, etc.
- Use only compatible containers for collecting waste. For example, do not use metal cans for corrosive waste; the corrosive will cause the metal to corrode, leak, and possibly spill.
- Label all containers to prevent the generation of “unknowns.” Label all stock, transfer, and waste containers appropriately. Ensure that all containers (including transfer containers) are labeled to identify contents, including the relevant hazardous constituents. Failure to label the contents of containers can result in very expensive disposal costs since unlabeled containers require special analytical or “fingerprinting” procedures to determine appropriate classification and disposal methods.
- Ensure that containers are in good condition, closed at all times, stored in bins or trays, adequately segregated, and inspected regularly.
- Use spirit-filled thermometers instead of mercury-filled thermometers.
- Substitute less hazardous chemicals in processes and experiments whenever possible.
- Avoid contamination of stock chemicals. Never return unused portions of a chemical to its original container. Estimate how much of a chemical will be needed for an experiment to avoid taking more than you need. In teaching labs, pre-weigh chemicals for undergraduate usage.
- Avoid buying chemicals in bulk. The cost of disposal usually outweighs any savings obtained by buying in bulk.
- Keep in mind that Reed College retains permanent liability for the management and appropriate disposal of your waste. As a means of ensuring compliance with the law, the DEQ and EPA may perform unannounced inspections at any time. Operations that do not meet regulatory requirements can result in substantial penalties, including fines of up to $25,000, per day, per violation. Over the past few years numerous universities and colleges have been fined millions of dollars for violating hazardous waste requirements.
B. Organic Solvents
Reed College produces a large variety of chemical solvent wastes. It may be practical to redistill commonly used solvents as part of the process for which they are used. For example, a lab that uses a gallon per week of ethyl acetate, resulting in a fairly clean and uncontaminated waste material, may consider distilling the waste material for reuse in the same project. This procedure is not suitable for those solvents that form explosive organic peroxides, such as ethers and alcohols; the distillation process concentrates and dries the peroxides, which can result in an explosive reaction.
Evaporation of chemicals in chemical fume hoods or by other means, if not part of an experimental procedure, is not allowed.
C. Redistributing and Returning Products
Materials which are no longer of use to a particular procedure or research project should be returned to the manufacturer or redistributed whenever possible. If from a laboratory, the generator of these “waste” materials should check with other laboratories to determine if the materials can be used in other projects. Reusing products saves both disposal costs and purchase costs. Conversely, before purchasing new materials such as paints, solvents, or other chemicals, the user should determine if other departments or research groups on campus use these the materials.
D. Neutralization and Deactivation
Certain hazardous chemicals can be rendered non-hazardous by specific neutralization and deactivation. These procedures are particularly effective when used in teaching labs as part of student responsibilities. Two especially valuable reference books for procedures on neutralization and deactivation of hazardous materials are:
Prudent Practices for Disposal of Chemicals from Laboratories, (National Research Council (U.S.), Committee on Hazardous substances in the Laboratory, 1995, National Academy Press, Washington, D.C.
Hazardous Chemicals Information and Disposal Guide, M.A. Armour, 2003, University of Alberta.
E. Non-Hazardous Waste
The following items are not considered hazardous. Collect them in disposable containers or plastic bags, clearly labeled as non-hazardous waste, and put into the regular trash. The pH of an aqueous solution of these materials must fall between 5 - 9. Otherwise, they are not allowed in the regular trash or down the sewer. If you are unsure whether any of these or other chemicals should go into the regular trash, consult with the EHS Coordinator.
Acetates: Ca, Na, NH4, and K
Amino acids and their salts
Citric acid and salts of Na, K, Mg, Ca, and NH4
Lactic acid and salts of Na, K, Mg, Ca, and NH4
Bicarbonates: Na, K
Borates: Na, K, Mg, Ca
Bromides: Na, K
Carbonates: Mg, Ca
Chlorides: Na, K, Mg, Ca
Iodides: Na, K
Oxides: B, Mg, Ca, Al, Si, Fe
Phosphates: K, Mg, Ca, NH4
Silicates: K, Mg, Ca
Sulfates: Na, K, Mg, Ca, NH4
Filter paper without hazardous chemical residue
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