||The nature of construction activities is to change, often significantly, many elements of the natural environment. Construction activities typically include clearing the land of vegetation, excavating earth, and compacting soil, all of which lead to increased stormwater runoff and higher erosion rates. Construction activities currently affect approximately 590,000 acres in the conterminous United States each year (USEPA, 2008c). Construction site discharges have been documented to increase the loadings of pollutants to surface waters. The most prominent and widespread pollutant is sediment. The level of sediment is often identified through the measurement of other pollutants in the water body, most notably turbidity, suspended solids, total suspended solids (TSS), suspended sediment concentration (SSC), or settleable solids. Other documented pollutants include metals, nutrients, and polycyclic aromatic hydrocarbons (PAHs). These pollutants can derive from construction equipment and materials or from contamination of a site prior to the start of construction activity. Other possible pollutants include pesticides, other toxic organics, and materials that exert biological oxygen demand (BOD) in surface waters. Construction activities mobilize these pollutants when they disturb soil and increase stormwater runoff within and from a site, making the pollutants available for discharge to surface waters.