Chemical Waste Segregation
Acids and Bases
Segregate containers of acids and bases from one another in individual, compatible containers while accumulating as waste. EHS will pick up concentrated acids and bases as hazardous waste. Do not discharge acids or bases containing heavy metals to the sanitary sewer, i.e., through the laboratory sinks. The Orange Water and Sewer Authority (OWASA) Sewer Use Ordinance prohibits discharge of aqueous liquids with a pH of <6 or >10 pH units. Do not mix acids and bases containing heavy metals with other acidic or basic wastes and do not include neutralization disposal of aqueous waste into the sanitary sewer as the last step in laboratory procedures.
Package oxidizers separately; store and accumulate away from organics including flammable materials. Oxidizers should never be stored or accumulated adjacent or proximate to any organic substances.
For the safety of hazardous waste personnel and to ensure compliance with the Resource Conservation and Recovery Act (RCRA) regulations, exercise care to identify reactive wastes. Although the process of using reactive chemicals in laboratory experiments usually eliminates the reactivity characteristic, some reactive chemicals can exhibit dangerous, residual properties. As an example, residual metallic sodium added to a solvent to remove water could result in a fire or explosion if that solvent is mixed with aqueous wastes. Likewise, you must label solutions containing sulfides and/or cyanides to alert personnel not to mix these with acid wastes. This mixing could release lethal amounts of toxic hydrogen sulfide (H2S) and/or hydrogen cyanide (HCN) gases. Due to the cost and hazards associated with shipping and disposing of reactives, make every effort to use or react the entire contents of the container. Make sure the responsible laboratory worker properly label these containers for disposal.
Segregate and collect halogenated and non-halogenated solvent wastes in separate waste containers. Please also note that in accordance with the OWASA Sewer Ordinance, pollutants that can create a fire or explosion hazard (e.g. non-halogenated hydrocarbons) should not be sewered. Moreover, toxic solvents including all chlorinated ethenes and ethanes must not be sewered to avoid potential upsets or adverse impacts to the biological treatment system at the OWASA publically owned treatment works (POTW).