Boric acid occurs naturally as a component of many minerals, in sea water, many plants, and in almost all fruits. Industrial preparation of boric acid is done by treating borax with a mineral acid, such as muriatic acid. Boric acid, usually sold in the form of colorless crystals, finds uses as an antiseptic, flame retardant, insecticide and as a precursor for certain chemicals in industry.
Put on a safety goggles, lab coat and a particulate respirator; where exposure to mist or dust is obvious. Use an air-supplied respirator when exposure levels are not known.
Shovel, sweep or scoop up boric acid and collect it in an appropriate glass or plastic container for disposal.
Dilute the sample with large amount of water and flush to sanitary sewer if you are disposing of a small amount of boric acid. Use landfill sites as well to dispose of small quantities of boric acid.
Consult local regulating authorities when dealing with large amounts of boric acid. Get proper advice from them since disposal rules vary a great deal from federal disposal regulations for different states. Manufacturers' boric acid material safety data sheet also recommend not spilling tonnage quantities to landfills.