Disposal of Chemicals to the Sewer

Certain liquid non-hazardous chemicals may be disposed of down the sink (sewer) under certain conditions.

More information and the list of eligible chemicals and their allowable concentration limits, including metals, formaldehyde, and ethanol, are on the EH&S website.

Dilution is not acceptable to meet these limits, in part because many chemicals partition to the biosolids separated from wastewater at the treatment plant.

Some hazardous chemicals may be treated before they are sewered. For example, we encourage you to neutralize your acids and bases (to a pH between 5.5 and 9) and treat ethidium bromide and formaldehyde. The successfully treated solutions can be sewered. For more information on treatment, please see the EH&S website.

If you do discharge eligible chemicals or treated chemicals to sewer, you must maintain a Sewer Discharge Log at that sink. Your completed logs should be kept for future possible inspections. We suggest that you keep them along with your other files related to environmental health and safety (such as your Laboratory Safety Manual). You may print a blank copy of the log from the EH&S website.