Many products found in your home are potentially hazardous substances. They consist of chemical compounds and can poison, corrode, explode or ignite when handled improperly. These substances are considered household hazardous waste (HHW) and can threaten human and environmental health. For this reason, HHW is not exempt from California hazardous waste laws. It is illegal to dispose of HHW in the trash or down household and storm drains. That is why Central Contra Costa and Mt. View Sanitary Districts built the HHW collection facility to give local residents and small businesses a convenient and environmentally safe means for HHW disposal and recycling.