13.1 INTRODUCTION

The Safe Drinking Water Act of 1974 and its Amendments of 1986 requires the U.S. Environmental Protection Agency (EPA) to establish goals for maximum levels for each contaminant that may have an adverse effect on people s health. Each goal must be set at a level at which no known or anticipated adverse effects on health occur, allowing for an adequate margin of safety (Clark et al., 1987). Maximum contaminant levels, which are the enforceable standards, must be set as close to the goals as feasible.

The Act has posed a major challenge to the United States drinking water industry because of the large number of regulations being implemented over a short time frame. The Safe Drinking Water Act and its Amendments of 1996 added even more complexity to the set of national regulations affecting the drinking water industry. Although most of the regulations promulgated under the 1996 Act and amendments have focused on treated water, there is substantial evidence that water quality can deteriorate between the treatment plant and the point of consumption. Factors that can influence the quality of water in distribution systems include the chemical and biological quality of source water; the effectiveness and efficiency of treatment processes; the adequacy of treatment facilities, storage facilities, and the distribution system; the age, type, design, and maintenance of the distribution network; and the quality of treated water (Clark and...