Median concentrations and instantaneous yields of alachlor, metolachlor, atrazine, cyanazine, and simazine were generally highest at sites in the Lower Susquehanna River Basin and in agricultural subbasins. Instantaneous herbicide yields are related to land use, hydrogeologic setting, streamflow yield, and agricultural row cropping practices. The significance of these relations may be affected by the interdependence of the factors. The percentage of basin area planted in corn is the most influential factor in the prediction of herbicide yield. Instantaneous yields of all five herbicides measured in June 1994 related poorly to averaged 1990–94 herbicide use. Annually averaged herbicide‐use data are too general to use as a predictor for short‐term herbicide yields. An evaluation of factors affecting herbicide yields could be refined with more‐current land use and land cover information and a more accurate estimate of the percentage of basin area planted in corn. Factors related to herbicide yields can be used to predict herbicide yields in other basins within the Chesapeake Bay watershed and to develop an estimate of herbicide loads to Chesapeake Bay.

In the aftermath of Hurricane Sandy, we saw pictures of the coastal devastation that reduced neighborhoods to rubble. We heard stories of brave firemen, policemen, neighbors, and other rescuers who helped frightened residents flee rising waters and burning buildings. People who could not help personally gave through the Red Cross. Certainly, this was a national tragedy that brought out the best in people. My personal heroes of Hurricane Sandy include the men and women of the USGS who worked tirelessly in the days ahead of the storm's landfall and, as the floodwaters retreated, continued to create and issue predictions of coastal impacts, deploy scientific instrumentation, and collect ephemeral data documenting the storm's impact. These efforts give us hope that our preparation for and response to the next superstorm will reduce the death toll, decrease the economic impact, and mitigate the loss of natural resources.

The mission of the U.S. Geological Survey (USGS) is to assess the quantity and quality of the earth resources of the Nation and to provide information that will assist resource managers and policymakers at Federal, State, and local levels in making sound decisions. Assessment of water-quality conditions and trends is an important part of this overall mission.One of the greatest challenges faced by water-resources scientists is acquiring reliable information that will guide the use and protection of the Nation's water resources. That challenge is being addressed by Federal, State, interstate, and local water-resource agencies and by many academic institutions. These organizations are collecting waterquality data for a host of purposes that include: compliance with permits and watersupply standards; development of remediation plans for a specific contamination problem; operational decisions on industrial, wastewater, or water-supply facilities; and research on factors that affect water quality. An additional need for water-quality information is to provide a basis on which regional and national-level policy decisions can be based. Wise decisions must be based on sound information. As a society we need to know whether certain types of water-quality problems are isolated or ubiquitous, whether there are significant differences in conditions among regions, whether the conditions are changing over time, and why these conditions change from place to place and over time. The information can be used to help determine the efficacy of existing water-quality policies and to help analysts determine the need for, and likely consequences of, new policies.To address these needs, the Congress appropriated funds in 1986 for the USGS to begin a pilot program in seven project areas to develop and refine the National WaterQuality Assessment (NAWQA) Program. In 1991, the USGS began full implementation of the program. The NAWQA Program builds upon an existing base of water-quality studies of the USGS, as well as those of other Federal, State, and local agencies. The objectives of the NAWQA Program are to:• Describe current water-quality conditions for a large part of the Nation's freshwater streams, rivers, and aquifers.• Describe how water quality is changing over time.• Improve understanding of the primary natural and human factors that affect water-quality conditions. This information will help support the development and evaluation of management, regulatory, and monitoring decisions by other Federal, State, and local agencies to protect, use, and enhance water resources.The goals of the NAWQA Program are being achieved through ongoing and proposed investigations of 59 of the Nation's most important river basins and aquifer systems, which are referred to as study units. These study units are distributed throughout the Nation and cover a diversity of hydrogeologic settings. More than two-thirds of the Nation's freshwater use occurs within the 59 study units and more than two-thirds of the people served by public water-supply systems...

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from the area were 77 tons per acre in 1981 (no vegetation), 32 tons per acre in 1982 (sparse vegetation), and 1.0 ton per acre in 1983 (well-established vegetation). The average annual yield below a sediment-control pond at the mine site in Fayette County was 0.19 ton per acre during the 27 months of data collection.