Household Hazardous Products
Many products found in your kitchen, bathroom, garage, or garden are potentially hazardous substances due to their chemical nature. When these products are dumped in the trash or poured down the drain, their hazardous chemicals may injure other people, contaminate drinking water sources, or harm the septic system. Many chemicals found in a septic system originate from household products that are improperly disposed of down the drain or used in concentrations higher than those recommended on the product label.
Some household products, such as ammonia, bleach, and laundry detergents, are intended to be poured down the drain. Under normal use conditions, the chemicals found in these cleaning solutions pose a minimal risk the environment because they are diluted in the septic tank or degraded along with household wastewater in the leach field.
Some household products, such as drain cleaners, contain chemicals that may harm the septic system or contaminate ground water. If these chemicals enter a septic tank in large doses or concentrated amounts, they may reach concentrations that are toxic to the beneficial bacteria that normally thrive in a septic system and treat household wastewater. If these chemicals flow unchanged from the septic tank, they may pass through the leach field and become ground water contaminants.
At any given time, the average household contains an estimated 3 to 5 gallons of products that are considered hazardous to human health and the environment. These household hazardous products, particularly those used for auto maintenance (fuels, motor oil, antifreeze), home repair (solvent-based lubricants), and lawn or garden care (pesticides), should not be disposed of in a manner that allows them to enter the septic system. They should be used up completely or taken to a local hazardous waste management facility.
Also, you may want to download this factsheet on Household Chemicals and Your Septic Tank.