To address unique permitting situations, the federal Clean Water Act (CWA) and National Pollution Discharge Elimination System (NPDES) permit regulations allow variances, or temporary deviations, from specific statutory or regulatory requirements under certain conditions. These variances may apply to either technology-based or water quality-based regulatory requirements. The Safe Drinking Water Act (SDWA) also allow variances to help public water systems achieve compliance with maximum contaminant levels.
The U.S. Environmental Protection Agency allows states to adopt variance provisions. According to Missouri Revised Statues, variances from state regulations may be authorized if certain conditions are met. These conditions are outlined in the Missouri Code of State Regulations. Learn more about variances, review variance requests in process or view completed variances below.