The Underground Storage Tank (UST) program applies to owners and operators of USTs used for the storage of hazardous substances. The majority of these USTs contain petroleum products. The purpose of the UST Program is to protect public health, the environment and groundwater. The goal of this program is to ensure that businesses and facilities with ongoing UST operations are properly permitted and meet the monitoring requirements applicable to their type of system. This is accomplished during plan check and inspection activities. Each UST facility is inspected annually.