Some chemicals that are not regulated as hazardous waste can be safely disposed of in the sanitary sewer or normal trash. The decision to use one of these methods of disposal must be made after careful consideration of the consequences.

Sink Disposal

Laboratory drains are connected to the local sanitary sewer system with the effluent eventually going to Hamilton's Wastewater Treatment Facility. Materials that cannot be disposed of via the sanitary sewer are materials that interfere with the treatment systems or chemicals that may cause a danger to the system or human health. These chemicals include but are not limited to:

• Any substance that alone or by interaction with other substances can cause fire or explosion. Prohibited materials include but are not limited to: solvents and alcohols, peroxides, oxidizers, sulfides, hydrides, carbides, chlorates, perchlorates, bromates, carbides, ethers, gasoline, kerosene. Generally this includes wastes that would be characterized as ignitable.
• Solid or viscous substances that may cause obstruction to the flow such as garbage, animal guts or tissues, hair, bones, feathers, sand, metal, glass, straw, plastics, wood, rags, oil, grease, or paper.
• Waste having a pH less than 5.0 or greater than 9.5. Wastewater with corrosive properties capable of causing damage or hazard to structures, equipment, or personnel at the treatment plant.
• Waste containing toxic substances in sufficient quantity to interfere with the wastewater treatment process, constitute a hazard to humans or animals, or create a toxic effect in the receiving waters.
• Any noxious or malodorous liquids, gases, or solids.
• Heavy metals.
• Waste of objectionable color such as dyes or stains.
• Waste with temperature that inhibits biological activity (exceeding 104^o F).
• Any wastewater containing radioactive isotopes. Certain amounts are acceptable. Contact the RSO prior to disposal.
• Any cyanide in excess of 2 mg/l by weight as CN.

Sink Disposal Procedures

• The materials must be water soluble.
• Drain disposal will be only into a drain that is connected to the sanitary sewer, never into a storm sewer drain that flows directly to surface water.
• The quantities of chemicals disposed of in the drain must be limited generally to not more than a few hundred grams or milliliters. Flush with at least 100 fold excess of water at the sink. Lab supervisors must monitor disposal for adherence to guidelines on type, quantity, rate, and flushing procedures.

Trash Disposal

Non-hazardous solids can be disposed of in the trash (no liquid wastes are allowed to go to the landfill). As mentioned before, the decision to use the trash must be made after careful consideration of the consequences. Non-hazardous materials will create a hazard if solid particles are inhaled or reach the eyes. A custodian may come in contact with it when he or she empties the trash. Our grounds grew could be exposed to the material when they handle the trash and compact it in the truck. All of our solid waste goes to the Madison County Landfill and will be there essentially forever.

Return to: Lab Waste Flowchart