Waste Segregation

Read through the entire list before deciding how your wastes should be segregated. If you have any question, contact the Chemistry Department Storeroom Manager at 253.879.3350, or go to Storeroom Manager's office in Thompson 308A.

The following groups of compatible wastes allow for the lowest disposal cost. The cost per gallon averages about $30 to $50. For unlabeled or incorrectly labeled bottles (please see the waste labeling guidelines), or bottles containing incompatible wastes, the cost can be astronomical — if the treatment facility refuses it, we are stuck with it. So please be careful labeling and segregating your wastes into the following groups:

Regulated Materials, the "P-list"
Washington State Ecology and the EPA regulate these extremely hazardous wastes which are acutely toxic and/or reactive. We are limited to generating campus wide no more than 1 kg of waste per month ten times a year. Do NOT mix these chemicals with other wastes, even minute quantities, or the whole container becomes a "P"-listed material! Check for P-Listed chemicals arranged by CAS number or alphabetically.

Halogenated Organic Solvent wastes
We must ship these wastes off campus for incineration. Included are: dichloromethane, chloroform, carbon tetrachloride, and any organic compounds that are bromonated, chlorinated, fluorinated, or iodated. (Never acidify halogenated solvents!)

Aliphatic Organic Solvent wastes <10% water
We ship these wastes off campus to be burned for fuels recovery (their BTU value).

Acetone
The acetone you use to wash and dry your glassware can be redistilled and recovered for use again. Keep this type of waste (washing and drying acetone) separate from reaction wastes. You must keep the same detailed records of what is in the acetone so that we can determine if it is suitable for distillation.

Peroxide-Forming Solvent wastes
Solvents capable of forming peroxides should be separated from other wastes and tested for peroxides weekly. Peroxides are highly explosive compounds sensitive to heat, friction, impact, and light. They form when stored for a month or longer regardless if exposed to air or not. This category includes: tetrahydrofuran, diethyl ether, cyclohexene, p-dioxane, and diisopropyl ether. We must ship these wastes off campus to be burned for fuel recovery (their BTU value).

Aromatic Polycyclic Organic wastes
We must ship these wastes off campus for incineration. Please keep dry solids separated from solutions.

Formaldehyde solutions
We must ship formaldehyde wastes off campus for incineration.

Mercury compounds, aqueous solutions, and elemental Mercury
Please keep dry solids separated from solutions. A mercury concentration greater than or equal to 0.2 mg/L is designated as hazardous waste and must be shipped off campus for disposal. All anions of mercury compounds are accepted with the exception of sulfide. These will go to a mercury recovery facility and retorted.

Lead compounds, aqueous solutions, and elemental Lead
Please keep dry solids separated from solutions. A lead concentration greater than or equal to 5.0 mg/L is designated as hazardous waste and must be shipped off campus for disposal. All anions of lead compounds are accepted with the exception of sulfide. These will go to a metals recovery facility and smelted.

Silver compounds, aqueous solutions, and elemental Silver
Please keep dry solids separated from solutions. A silver concentration greater than or equal to 5.0 mg/L is designated as hazardous waste and must be shipped off campus for disposal. All anions of silver compounds are accepted with the exception of sulfide. These will go to a metals recovery facility and smelted.

Arsenic and Osmium Tetroxide
We must ship these wastes off campus for encapsulation and burial. An arsenic concentration greater than or equal to 5.0 mg/L is designated as hazardous waste and must be shipped off site for disposal.

Other metal compounds and aqueous wastes
For some specific metals, concentrations greater than or equal to the following limits are designated as hazardous waste and must be shipped off campus: Barium = 100 mg/L, Cadmium = 1.0 mg/L, Chromium = 5.0 mg/L, and Selenium = 1.0 mg/L. For other metals, like nickel copper or tin, etc., check the Toxic Category Table in WAC 173-303-100 for the EC value (Equivalent Concentration). Please keep dry solids separated from solutions. All anions of these metal compounds are accepted with the exception of sulfide. These will go to a metals recovery facility and smelted.

Acids
We are permitted to neutralize acidic solutions to a pH range between 5 and 9. This applies to these common lab acids only: nitric acid, sulfuric acid, hydrochloric acid, and acetic acid.

Bases
We are permitted to neutralize basic solutions to a pH range between 6 and 9. This applies to common lab bases only: potassium hydroxide, sodium hydroxide, and ammonium hydroxide.

Azide compounds and solutions
Sodium azide is a "P-listed" hazardous waste and is regulated — we are limited to 1 kg per month for all "P-listed" chemicals campus wide. Azides are also highly explosive, especially if they are allowed to react with metals. Please keep dry solids separated from solutions. Azide wastes must be shipped off campus for special treatment. Solutions less than 10% are accepted — solutions greater than 10% are refused by the waste treatment facility.

Cyanide compounds and solutions
Sodium and potassium cyanide are "P-listed" hazardous wastes and are regulated — we are limited to 1 kg per month for all "P" listed chemicals campus wide. Please keep dry solids separated from solutions. Cyanide wastes must be shipped off campus for special treatment. Never acidify cyanide solutions!

Sulfide compounds and solutions
Please keep dry solids separated from solutions. Sulfide wastes must be shipped off campus for special treatment.

Filtering Aids
Agents that are used for filtering such as, Silica Gel, Sand, Celite, and Diatomaceous Earth, are to be treated as a hazardous material since it is contaminated with chemical products and by-products. Label it with all the hazard warnings as if it was reactants and products and by-products.

Other Chemical Wastes
If your waste does not fit into any of the above categories, contact the chemistry storeroom manager. Either your waste is not regulated, or there are special regulations for it — the storeroom manager will help you determine this.

Surplus Reagents
If you are finished with your project, see this section for information on what to do with your left over reagents.

Empty Bottles
If you empty a bottle of reagent, see this section for what to do next.

In General
Keep these wastes separated into the above categories. If in doubt, do not mix your wastes — keep them separated no matter how small the amount. If you did all your homework as found in the guidelines for setting up your experiment and purchasing chemicals, you will not have problems with wastes being removed from your lab.