Performance-based approach for groundwater systems

摘要

With respect to microbiological contamination, operators and managers at public water systems (PWSs) served by groundwater sources have used information from a variety of sources to evaluate the quality and susceptibility of their water. Sanitary surveys (USEPA, 1989b) conducted by regulators or their agents provide an extramural and objective evaluation of physical defects as well as operational or management procedures that might affect water quality. Routine regulatory monitoring for total coliform organisms (additionally, fecal coliform or Escherichia coli organisms are also monitored if total coliform organisms are present) gives an indication of finished water quality at the time and place of the monitoring. Limited process control monitoring (disinfectant residual is probably the most common) also adds valuable information. Armed with monitoring data, sanitary survey findings, and a knowledge of best operational and management practices, water system managers can attain a level of security or concern. There exists, however, a lack of generally accepted water quality performance indicators that can be used for process control to assess the integrity of each barrier to contamination.