WATER QUALITY OF STORMWATER RUNOFF FROM TEN INDUSTRIAL SITES1

ABSTRACT: This study was to designed to determine concentrations of selected metals, organic compounds, pesticides, and conventional pollutants in stormwater runoff from two North Carolina businesses in each of the following five general industrial groups: auto salvage, metal fabrication, scrap and recycling, vehicle maintenance, and wood preserving facilities. The sampling procedure involved collecting a first flush sample of runoff from a single storm event and both first flush and composite samples of runoff from three consecutive storm events. Analysis of samples collected during the first flush indicated that zinc and copper were the most common of the 13 metals included in the analysis. Additional analysis documented that several volatile organic, semi-volatile organic, or pesticide compounds including acrolein, methylene chloride, xylenes, toluene, tetrachloroethylene, trichloroethylene, pentachlorophenol, and aldrin were also found in the first flush samples. Concentrations of aggregate organics, nitrogen, phosphorus, and sediment were determined in both first flush and three-hour composite samples. Concentrations of pollutants in first flush samples were similar to those in corresponding composite samples.     

MODELING THE EFFECTS OF URBANIZATION ON BASIN WATER YIELD AND RESERVOIR SEDIMENTATION1

ABSTRACT: The dam impounding White Rock Lake was completed in 1910 to provide water for the City of Dallas. Since then, land use on the watershed has changed from entirely rural to over 77 percent urban. A model called SWRRB (Simulator for Water Resources in Rural Basins) was utilized to determine the effect of urbanization on water and sediment entering the lake. The simulation results show that, if urbanization had not occurred, then the annual surface runoff would be 135 mm rather than 151 mm and the annual sediment yield would be 4.4 t/ha rather than 4.1 t/ha. Also, the effect of urbanization on delivery ratios was shown and a positive linear correlation was found. Finally, the weather generator in SWRRB was utilized to estimate the loss of reservoir capacity until 2050 for three different land use management scenarios.     

RAPID WATER TABLE RISE1

ABSTRACT: There are unpublished reports of rapid and large rises in the water table which are out of proportion to the infiltrated volumes of water. The phenomenon seems to result from the conversion of a tension saturated zone to phreatic water by one of several mechanisms. The effect could be triggered when the tension saturated zone intersects: the ground surface, a saturated soil horizon, or a coarse zone. The phenomenon could prove to be a common link in explaining several seemingly diverse phenomena which characterize non-Hortonian runoff in a humid environment. Under certain conditions storm peaks are dominated by flow from small, restricted, “variable source” areas that contributed runoff when saturated from below by rising water tables; for other streams, ground water input forms the major part of the flood peak. The explanation for these observations could lie in an understanding of the rapid water table rise phenomenon. Such a mechanism. if widespread, would provide the means for producing saturation at or near the surface shortly after rainfall commences. The phenomenon should be documented and closely analyzed from a number of perspectives to define its true role in the hydrology of humid environments.     

FIRST-YEAR EFFECTS OF CLEARCUTTING AN OAK-HICKORY WATERSHED ON WATER YIELD1

ABSTRACT: Two intermittent streams on oak-hickory watersheds in southern Illinois were gaged with a V-notch weir and sampled with an automatic water sampler. Baseline data was collected for a period of three years. Flow volume showed large variations between years and watersheds. Water samples were analyzed for Na, K, Ca, Mg, ortho-P, and NO₃-N. Water quality was consistently high, but there were significant differences between the watersheds during the calibration period. One watershed was clearcut in November 1979. One year of postharvest data has been analyzed. Flow volume increased 95 percent, but there was no evidence of increased sedimentation. There were significant increases in the stream water concentrations of K, Mg, and NO₃-N of 18 percent, 8 percent, and 274 percent, respectively. Nutrient budgets for the site were not adversely affected by the harvest. The clearcutting operation appears to have had a small impact on the watershed due to minimal disturbance during the logging and below normal precipitation the first year following the harvest.     

Construing of self and others at work in the early years of corporate careers

Research has examined personal change and stability in early adulthood but generally with standardized scales and without inviting explicit comparison of self with other people. The present work uses the repertory grid method to examine how graduates construe themselves and others during early career. Ninety-four graduate entrants to a multinational corporation with zero to four years' tenure completed repertory grids on two occasions one year apart. Results shed much light on the graduates' concepts of self relative to others in their work setting, and how these change over time. The graduates generally had fairly positive self concepts, though these did not become more positive with tenure. Most saw themselves much as they thought others saw them. Change in concepts of self varied greatly between graduates, as did the constructs on which those concepts were described. The results cast further doubt on whether organizational socialization affects people in uniform ways.     

Evaluating the cumulative effects of alteration on New England wetlands

In New England, patterns of glacial deposition strongly influence wetland occurrence and function. Many wetlands are associated with permeable deposits and owe their existence to groundwater discharge. Whether developed on deposits of high or low permeability, wetlands are often associated with streams and appear to play an important role in controlling and modifying streamflow. Evidence is cited showing that some wetlands operate to lessen flood peaks, and may have the seasonal effect of increasing spring discharges and depressing low flows. Wetlands overlying permeable deposits may be associated with important aquifers where they can produce slight modifications in water quality and head distribution within the aquifer. Impacts to wetlands undoubtedly will affect these functions, but the precise nature of the effect is difficult to predict. This is especially true of incremental impacts to wetlands, which may, for example, produce a change in streamflow disproportionate to wetland area in the drainage basin, i.e., a nonlinear effect as defined by Preston and Bedford (1988). Additional research is needed before hydrologic function can be reliably correlated with physical properties of wetlands and landscapes.A model is proposed to structure future research and explore relationships between hydrologic function and physical properties of wetlands and landscapes. The model considers (1) the nature of the underlying deposits (geologic type), (2) location in the drainage basin (topographic position), (3) relationship to the principal zone of saturation (hydrologic position), and (4) hydrologic character of the organic deposit.