The Permit Compliance System (PCS) is an EPA national computerized management information system that records water-discharge permit data on more than 64,000 wastewater treatment facilities nationwide. This system automates entry, updating, and retrieval of National Pollutant Discharge Elimination System (NPDES) data and tracks permit issuance, permit limits, monitoring data, and other data pertaining to facilities regulated under NPDES. There are approximately 49,000 industrial facilities and 15,000 municipal facilities regulated by NPDES. The Current Effluent Limits File contains detailed information describing each outfall for approximately 7100 major active permitted facilities and the associated outfall permit requirements for the current NPDES permit such as pollutant name,permit limit values, and limit start and end dates - which indicate when a facility may discharge. For each permitted facility there may be multiple outfalls and thus, multiple sets of pipe schedule data. Because effluent limits may cover a number of pollutants, for each set of pipe schedule data there may be muliple sets of parameter data. This data is updated twice a year.