UAMS Chemical Disposal Staff

Program

The primary goal in handling and disposal of hazardous waste is to do so in a manner which prevents harm to human health and the environment. Extensive federal, state, and local regulations govern hazardous waste management. The University is covered by these regulations, which are beyond the scope of this guide but in general, they regulate the handling, transportation, storage, and disposal of waste. The regulations also require extensive record keeping and a “cradle to grave” tracking system which tracks hazardous wastes from their point of generation through disposal. This allows all waste to be accounted for at any stage between generation and disposal.

What is a Hazardous Waste?

In general hazardous waste is either:

• Listed in one of four lists that the EPA has generated, or;
• Exhibits a characteristic that the EPA has identified as making it a hazardous waste.

The initial step toward proper chemical and hazardous waste management is to determine whether the waste is hazardous. This determination is important to meet environmental regulations and to properly complete the Chemical Pickup Request Form.

For the purpose of this program, chemicals that should be considered wastes are those which:

• are contaminated or spent and can no longer be used OR
• are outdated chemicals OR
• are chemicals in poor containers

Chemicals which have not exceeded their shelf life, are in good containers, and could be used by someone else are NOT classified as a waste. These chemicals should also be collected by OH&S where they may be reused by other laboratories, or sent for proper disposal.

Listed Hazardous Wastes

EPA has developed several lists of substances which have been shown to have toxic, carcinogenic, mutagenic, or teratogenic effects on humans or other life forms. Chemicals with physical characteristics such as ignitability, corrosivity, or reactivity are also listed. Because there are over 700 chemicals on these lists and the regulatory principles are not intuitive, determination whether or not a waste is hazardous using EPA lists is a complex task which requires some degree of familiarity with the regulations. Many chemicals which are at least moderately toxic, moderately corrosive or combustible do not appear on these lists. Therefore, any chemicals suspected of having any toxic or hazardous properties should be handled by OH&S.

Characteristic Hazardous Wastes

Certain wastes which are not specifically listed are regulated as hazardous because they exhibit one or following characteristics: ignitability, reactivity, corrosivity, or toxicity. If wastes exhibit any of these characteristics, they are regulated as hazardous, and arrangements for disposal must be made with OH&S.

1. Ignitable Wastes - Any liquid waste having a flashpoint of less than 140 degrees F. is considered an ignitable hazardous waste. The following are examples of ignitable wastes: ethyl ether, methanol, ethanol, acetone, toluene, benzene & xylene.



2. Corrosive Wastes - Any waste with a pH less than 2.0 or greater than 12.5 or which corrodes steel at a rate greater than 6 mm per year is regulated as a corrosive waste. Wastes in this category include many acids and bases. The following are examples of corrosives wastes: sulfuric acid, ammonium hydroxide, nitric acid, sodium hydroxide, and hydrofluoric acid.



3. Reactive Wastes - Any waste that is shock-sensitive, violently unstable, reacts violently with air or water, or generates cyanide or sulfide gases is regulated as a reactive waste. some common chemicals are picric acid and other polynitroaromatics, old ethers and other peroxide forming organics, organic peroxides, ammonium perchlorate and metal perchlorates.



4. Toxic Wastes - Any waste which equals or exceeds a designated concentration of certain toxic compounds is regulated as a characteristically toxic hazardous waste. The test to determine these concentrations is known as the TCLP (Toxicity Characteristic Leaching Procedure). It determines the amount of the toxic compound that leaches from the waste, simulating what could leach into the environment from an improperly disposed waste.

Non-Regulated Wastes

Many chemicals are not considered hazardous waste using the “Listed Waste” or “Characteristic Waste” criteria described above. However, these chemicals may be at least moderately toxic, moderately corrosive or combustible and should be collected by OH&S to ensure safe handling and disposal. No chemical or chemical mixture should be poured down the drain or thrown in the trash.

Materials with strong odor must not be disposed of via the sewer but should be maintained in sealed containers and collected by OH&S.

Unidentified Wastes

All waste to be picked up by OH&S must be accurately described or they cannot be properly segregated. This greatly affects the safety hazards with handling and storage of these materials. From a regulatory standpoint, OH&S is prohibited from accepting unidentified wastes for transportation to storage. When an unidentified material or waste is discovered, an attempt to identify its contents should be immediately undertaken.

How to get Hazardous and Chemical Waste Picked Up

Laboratory Close-outs

All wastes and unwanted chemicals should be routinely purged from a chemical storage area. This practice becomes more critical when a facility is scheduled for relocation or renovation. All chemical users that are scheduled to move as part of their relocation plans should provide OH&S with as much advanced notification as possible.

For any other information regarding chemical disposal or environmental regulations please contact Michael W. Webb, Ph.D., PEM Environmental Programs Manager for OH&S at 686-6958 or email mwwebb@uams.edu