Rock salt comprises approximately 94-percent sodium chloride, and has a characteristic reddish-brown color owing to the presence of an insoluble clay called marl, which is a chief impurity. Rock salt is necessary when making homemade ice cream, and it's also a natural food preservative. Perhaps the most common use for rock salt is as a deicing agent; it melts snow and ice, and protects surfaces from ice formation. In small amounts, rock salt is not harmful. In larger quantities, it can be irritating to skin and eyes. If you spill a large amount of sock salt, remain calm. It's easy to dispose of rock salt safely.
Put on gardening gloves or powderless rubber gloves. Prolonged contact with salt draws out the skin's natural moisture, and may cause cracking and irritation.
Scoop up any spilled rock salt. Use a brush or broom to sweep small spills into a dustpan. Larger spills may require a shovel.
Place the salt into an approved container. Most waste management facilities recommend a plastic container that seals tightly. If you are unsure of the approved container in your area, contact your local waste management facility.
Use warm water to rinse any surfaces the salt touched.
Dispose of the rock salt at your local waste management facility, or household hazardous waste center.