increase the certainty of detecting potential water quality problems through monitoring. The categorization of chemicals and microorganisms into groups with similar fate and transport properties and similar behavior in treatment steps is one approach to streamline the list of potential contaminants to be monitored. It is unclear whether we can continue to rely on total coliform and Escherichia coli indicator bacteria to characterize the microbial quality of water as the drinking water industry has done for decades. Such methodologies will improve the ability of MUS systems of a variety of sizes to engage in sound monitoring practices.

Recommendation: Research should be conducted to understand whether we can rely on monitoring surrogate or indicator parameters as a substitute for analysis of long lists of chemicals and microorganisms (Chapter 6).

Conclusion: Surface spreading facilities sometimes require large amounts of land, particularly where large amounts of water are recharged or the geology is not ideal. Recharge well systems require less land but may have as many different factors to consider in their placement. Optimization of recharge facility placement is important but not always well understood.

Recommendation: If there is some degree of freedom in site selection for recharge wells or basins, a location suitability assessment may be useful in site optimization. Factors such as ecological suitability, existing uses of the aquifer, groundwater quality, aquifer transmissivity, road density, land use and ownership, and access to power lines can be weighed in such an analysis (Chapter 6).

NRC (National Research Council). 1994. Ground Water Recharge Using Waters of Impaired Quality. Washington, DC: National Academy Press.